Plastics Information

有关塑料环保的新闻报道英语作文英文回答：Plastic's Peril: Environmental Impacts and Solutions.Plastic has become an indispensable material in our modern world, finding applications in a vast array of products from packaging to construction. However, its widespread use has come at a steep environmental cost.1. Pollution and Waste:Plastic pollution poses a significant threat to our oceans, waterways, and ecosystems. Discarded plastic items can take centuries to decompose, fragmenting into microplastics that accumulate in the environment. These microplastics can be ingested by marine life, leading to health problems and even death.Furthermore, plastic waste management is a majorchallenge. In many countries, plastic is disposed of in landfills, where it can leach toxic chemicals into the groundwater and soil. Alternatively, plastic is often incinerated, releasing harmful emissions into the atmosphere.2. Greenhouse Gas Emissions:The production and disposal of plastic contribute significantly to greenhouse gas emissions. The extraction of fossil fuels, the manufacturing of plastic products, and the incineration or landfilling of plastic waste all release carbon dioxide and other greenhouse gases into the atmosphere, exacerbating climate change.3. Human Health Impacts:Studies have linked exposure to plastics to a range of health issues, including hormonal imbalances, reproductive problems, and developmental disorders. Chemicals used in the production of plastics, such as phthalates and BPA, have been found to interfere with the human endocrinesystem and have been associated with various adverse health effects.Solutions:Addressing the environmental impacts of plastic requires a comprehensive approach involving both individual and collective efforts.1. Reduce Consumption:Reducing our consumption of single-use plastics is a crucial step. We can opt for reusable bags, water bottles, and utensils instead of their plastic counterparts.2. Enhance Recycling and Composting:Improving waste management systems and increasing recycling rates is essential for diverting plastic from landfills and incinerators. Additionally, composting biodegradable plastics can reduce their environmental impact.3. Invest in Sustainable Alternatives:Research and development should focus on finding sustainable alternatives to plastics. Biodegradable materials derived from plant-based sources and innovative recycling technologies offer promising solutions.4. Raise Awareness:Raising awareness about the environmental consequences of plastic consumption is crucial. Public education campaigns and advocacy groups can play a vital role in promoting responsible plastic use and inspiring individuals to make environmentally conscious choices.5. Government Regulations:Government regulations can play a significant role in reducing plastic pollution and promoting sustainable practices. Bans on certain single-use plastics, extended producer responsibility schemes, and incentives forrecycling can contribute to a more sustainable plastic economy.中文回答：塑料的危害，对环境的影响和解决方案。

Plastic: A Double-Edged SwordPlastics, a ubiquitous material in modern society, has revolutionized our daily lives in countless ways. From packaging food and beverages to building aircraft and spacecraft, its versatility and durability have made it indispensable. However, this same plastic that has brought so much convenience and comfort has also become a menace to our environment and health.The widespread use of plastic has led to a significant increase in waste generation. Single-use plastics, such as bags, bottles, and containers, are discarded after a brief period of usage, often ending up in landfills or polluting our oceans and waterways. This plastic waste not only takes up valuable space but also poses a threat to wildlife and marine life, causing entanglement, ingestion, and even death.Moreover, the production of plastic involves the use of fossil fuels, a non-renewable resource. The burning of plastic waste generates harmful emissions, contributing to climate change and global warming. Additionally, some plastics contain harmful chemicals that can leak into thesoil and water, posing a threat to human health and ecological systems.Despite these negative impacts, plastic is not entirely without merit. It has enabled significant advancements in medicine, technology, and other fields. For instance, medical implants, such as pacemakers and artificial joints, are made from plastic, improving the quality of life for millions. Plastics are also used in solar panels and wind turbines, helping to power our world in a more sustainable manner.The key to addressing the challenges posed by plastic lies in responsible use and recycling. Consumers can reduce their plastic waste by using reusable alternatives, such as cloth bags and containers, and by recycling their plastic waste whenever possible. Governments and industries must also take measures to encourage the development and use of biodegradable plastics and other sustainable alternatives. In conclusion, plastic is a double-edged sword. While it has brought remarkable advancements and convenience to our lives, its unchecked use and disposal have also created serious environmental and health problems. By adoptingresponsible practices and fostering innovation, we can harness the benefits of plastic while mitigating its negative impacts, ensuring a sustainable future for all.**塑料：一把双刃剑**塑料，这种在现代社会中无处不在的材料，以无数种方式彻底改变了我们的日常生活。

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剑桥雅思阅读5原文(test2)READING PASSAGE 1You should spend about 20 minutes on Questions 1-13, which are based on Reading Passage 1 below.BAKELITEThe birth of modern plasticsIn 1907, Leo Hendrick Baekeland, a Belgian scientist working in New York, discovered and patented a revolutionary new synthetic material. His invention, which he named ‘Bakelite,’was of enormous technological importance, and effectively launched the modern plastics industry.The term ‘plastic’ comes from the Greek plassein, meaning ‘to mould’. Some plastics are derived from natural sources, some are semi-synthetic (the result of chemical action on a natural substance), and some are entirely synthetic, that is, chemically engineered from the constituents of coal or oil. Some are ‘thermoplastic’, which means that, like candlewax, they melt when heated and can then be reshaped. Others are ‘thermosetting’: like eggs, they cannot revert to their original viscous state, and their shape is thus fixed for ever. Bakelite had the distinction of being the first totally synthetic thermosetting plastic.The history of today’s plastics begins wit h the discovery of a series of semi-synthetic thermoplastic materials in the mid-nineteenth century. The impetus behind the development ofthese early plastics was generated by a number of factors —immense technological progress in the domain of chemistry, coupled with wider cultural changes, and the pragmatic need to find acceptable substitutes for dwindling supplies of ‘luxury’ materials such as tortoiseshell and ivory.Baekeland’s interest in plastics began in 1885 when, as a young chemistry student in Belgium, he embarked on research into phenolic resins, the group of sticky substances produced when phenol (carbolic acid) combines with an aldehyde (a volatile fluid similar to alcohol). He soon abandoned the subject, however, only returning to it some years later. By 1905 he was a wealthy New Yorker, having recently made his fortune with the invention of a new photographic paper. While Baekeland had been busily amassing dollars, some advances had been made in the development of plastics. The years 1899 and 1900 had seen the patenting of the first semi-synthetic thermosetting material that could be manufactured on an industrial scale. In purely scientific terms, Baekeland’s major contribution to the field is not so much the actual discovery of the material to which he gave his name, but rather the method by which a reaction between phenol and formaldehyde could be controlled, thus making possible its preparation on a commercial basis. On 13 July 1907, Baekeland took out his famous patent describing this preparation, the essential features of which are still in use today.The original patent outlined a three-stage process, in which phenol and formaldehyde (from wood or coal) were initially combined under vacuum inside a large egg-shaped kettle. The result was a resin known as Novalak which became soluble and malleable when heated. The resin was allowed to cool in shallow trays until it hardened, and then broken up and ground intopowder. Other substances were then introduced: including fillers, such as woodflour, asbestos or cotton, which increase strength and moisture resistance, catalysts (substances to speed up the reaction between two chemicals without joining to either) and hexa, a compound of ammonia and formaldehyde which supplied the additional formaldehyde necessary to form a thermosetting resin. This resin was then left to cool and harden, and ground up a second time. The resulting granular powder was raw Bakelite, ready to be made into a vast range of manufactured objects. In the last stage, the heated Bakelite was poured into a hollow mould of the required shape and subjected to extreme heat and pressure, thereby ‘setting’ its form for life.The design of Bakelite objects, everything from earrings to television sets, was governed to a large extent by the technical requirements of the molding process. The object could not be designed so that it was locked into the mould and therefore difficult to extract. A common general rule was that objects should taper towards the deepest part of the mould, and if necessary the product was molded in separate pieces. Moulds had to be carefully designed so that the molten Bakelite would flow evenly and completely into the mould. Sharp corners proved impractical and were thus avoided, giving rise to the smooth, ‘streamlined’ style popular in the 1930s. The thickness of the walls of the mould was also crucial: thick walls took longer to cool and harden, a factor which had to be considered by the designer in order to make the most efficient use of machines.Baekeland’s inve ntion, although treated with disdain in its early years, went on to enjoy an unparalleled popularity which lasted throughout the first half of the twentieth century. It became the wonder product of the new world of industrialsexpansion —‘the material of a thousand uses’. Being both non-porous and heat-resistant, Bakelite kitchen goods were promoted as being germ-free and sterilisable. Electrical manufacturers seized on its insulating properties, and consumers everywhere relished its dazzling array of shades, delighted that they were now, at last, no longer restricted to the wood tones and drab browns of the preplastic era. It then fell from favour again during the 1950s, and was despised and destroyed in vast quantities. Recently, however, it has been experiencing something of a renaissance, with renewed demand for original Bakelite objects in the collectors’ marketplace, and museums, societies and dedicated individuals once again appreciating the style and originality of this innovative material.Questions 1-3Complete the summary.Choose ONE WORD ONLY from the passage for each answer.Write your answers in boxes 1-3 on your answer sheet.Some plastics behave in a similar way to 1……… in that they melt under heat and can be moulded into new forms. Bakelite was unique because it was the first material to be both entirely 2……… in origin, and thermosetting.There were several reasons for the research into plastics in the nineteenth century, among them the great advances that had been made in the field of 3…………a nd the search for alternatives to natural resources like ivory.Questions 4-8Complete the flow-chart.Choose ONE WORD ONLY from the passage for each answer.Write your answers in boxes 4-8 on your answer sheet.The Production of Bakelite图片6Questions 9 and 10Choose TWO letters A-E.Write your answers in boxes 9 and 10 on your answer sheet.NB Your answers may be given in either order.Which TWO of the following factors influencing the design of Bakelite objects are mentioned in the text?A the function which the object would serveB the ease with which the resin could fill the mouldC the facility with which the object could be removed from the mouldD the limitations of the materials used to manufacture the mouldE the fashionable styles of the periodQuestions 11-13Do the following statements agree with the information given in Reading Passage 1?In boxes 11-13 on your answer sheet, writeTRUE if the statement agrees with the informationFALSE if the statement contradicts the informationNOT GIVEN if there is no information on this11 Modern-day plastic preparation is based on the same principles as that patented in 1907.12 Bakelite was immediately welcomed as a practical and versatile material.13 Bakelite was only available in a limited range of colours.READING PASSAGE 2You should spend about 20 minutes on Questions 14-27, which are based on Reading Passage 2 below.What’s so funny?John McCrone reviews recent research on humorThe joke comes over the headphones: ‘Which side of a dog has the mos t hair? The left.’ No, not funny. Try again. ‘Which side of a dog has the most hair? The outside.’ Hah! The punchline is silly yet fitting, tempting a smile, even a laugh. Laughter has always struck people as deeply mysterious, perhaps pointless. The writer Arthur Koestler dubbed it the luxury reflex: ‘unique in that it serves no apparent biological purpose. ’Theories about humour have an ancient pedigree. Plato expressed the idea that humor is simply a delighted feeling of superiority over others. Kant and Freud felt that joke-telling relies on building up a psychic tension which is safely punctured by the ludicrousness of the punchline. But most modern humor theorists have settled on some version of Aristotle’s belief that jokes are based on a reaction to or resolution of incongruity, when the punchline is either a nonsense or, though appearing silly, has a clever second meaning.Graeme Ritchie, a computational linguist in Edinburgh, studies the linguistic structure of jokes in order to understand not only humor but language understanding and reasoning in machines. He says that while there is no single format for jokes, many revolve around a sudden and surprising conceptual shift. A comedian will present a situation followed by an unexpected interpretation that is also apt.So even if a punchline sounds silly, the listener can see there is a clever semantic fit and that sudden mental ‘Aha!’ is the buzz that makes us laugh. Viewed from this angle, humor is just a form of creative insight, a sudden leap to a new perspective.However, there is another type of laughter, the laughter of social appeasement and it is important to understand this too.Play is a crucial part of development in most young mammals. Rats produce ultrasonic squeaks to prevent their scuffles turning nasty. Chimpanzees have a ‘play-face’ — a gaping expression accompanied by a panting ‘ah ah’ noise. In humans, these signals have mutated into smiles and laughs. Researchers believe social situations, rather than cognitive events such as jokes, trigger these instinctual markers of play or appeasement. People laugh on fairground rides or when tickled to flag a play situation, whether they feel amused or not.Both social and cognitive types of laughter tap into the same expressive machinery in our brains, the emotion and motor circuits that produce smiles and excited vocalisations. However, if cognitive laughter is the product of more general thought processes, it should result from more expansive brain activity.Psychologist Vinod Goel investigated humour using the new technique of ‘single event’ functional magnetic resonance imaging (fMRI). An MRI scanner uses magnetic fields and radio waves to track the changes in oxygenated blood that accompany mental activity. Until recently, MRI scanners needed several minutes of activity and so could not be used to track rapid thought processes such as comprehending a joke. New developments now allow half-second ‘snapshots’ of all sorts of reasoning and problem-solving activities.Although Goel felt being inside a brain scanner was hardly the ideal place for appreciating a joke, he found evidence that understanding a joke involves a widespread mental shift. His scans showed that at the beginning of a joke the listener’s prefrontal cortex lit up, particularly the right prefrontal believed to be critical for problem solving. But there was also activity in the temporal lobes at the side of the head (consistent withattempts to rouse stored knowledge) and in many other brain areas. Then when the punchline arrived, a new area sprang to life — the orbital prefrontal cortex. This patch of brain tucked behind the orbits of the eyes is associated with evaluating information.Making a rapid emotional assessment of the events of the moment is an extremely demanding job for the brain, animal or human. Energy and arousal levels may need to be retuned in the blink of an eye. These abrupt changes will produce either positive or negative feelings. The orbital cortex, the region that becomes active in Goel’s experiment, seems the be st candidate for the site that feeds such feelings into higher-level thought processes, with its close connections to the brain’s sub-cortical arousal apparatus and centres of metabolic control.All warm-blooded animals make constant tiny adjustments in arousal in response to external events, but humans, who have developed a much more complicated internal life as a result of language, respond emotionally not only to their surroundings, but to their own thoughts. Whenever a sought-for answer snaps into place, there is a shudder of pleased recognition. Creative discovery being pleasurable, humans have learned to find ways of milking this natural response. The fact that jokes tap into our general evaluative machinery explains why the line between funny and disgusting, or funny and frightening, can be so fine. Whether a joke gives pleasure or pain depends on a person’s outlook.Humor may be a luxury, but the mechanism behind it is no evolutionary accident. As Peter Derks, a psychologist at William and Mary Colleg e in Virginia, says: ‘I like to think of humour as the distorted mirror of the mind. It’s creative, perceptual, analytical and lingual. If we can figure out how the mindprocesses humor, then we’ll have a pretty good handle on how it works in general.’Questions 14-20Do the following statements agree with the information given in Reading Passage 2?In boxes 14-20 on your answer sheet, writeTRUE if the statement agrees with the informationFALSE if the statement contradicts the informationNOT GIVEN if there is no information on this14 Arthur Koestler considered laughter biologically important in several ways.15 Plato believed humour to be a sign of above-average intelligence.16 Kant believed that a successful joke involves the controlled release of nervous energy.17 Current thinking on humour has largely ignored Aristotle’s view on the subject.18 Graeme Ritchie’s work links jokes to artificial intelligence.19 Most comedians use personal situations as a source of humour.20 Chimpanzees make particular noises when they are playing.Questions 21-23The diagram below shows the areas of the brain activated by jokes.Label the diagram.Choose NO MORE THAN TWO WORDS from the passage for each answer.Write your answers in boxes 21-23 on your answer sheet.Questions 24-27Complete each sentence with the correct ending A-G below.Write the correct letter A-G in boxes 24-27 on your answer sheet.24 One of the brain’s most difficult tasks is to25 Because of the language they have developed, humans26 Individual responses to humour27 Peter Derks believes that humourA react to their own thoughts.B helped create language in humans.C respond instantly to whatever is happening.D may provide valuable information about the operation of the brain.E cope with difficult situations.F relate to a person’s subjective views.G led our ancestors to smile and then laugh.READING PASSAGE 3You should spend about 20 minutes on Questions 28-40, which are based on Reading Passage 3 below.The Birth of Scientific EnglishWorld science is dominated today by a small number of languages, including Japanese, German and French, but it is English which is probably the most popular global language of science. This is not just because of the importance of English-speaking countries such as the USA in scientific research; the scientists of many non-English-speaking countries find that they need to write their research papers in English to reach a wide international audience. Given the prominence of scientific English today, it may seem surprising that no one really knew how to write science in English before the 17th century. Before that, Latin was regarded as the lingua franca1 for European intellectuals.The European Renaissance (c. 14th-16th century) is sometimes called the ‘revival of learning’, a time of renewed interest in the ‘lost knowledge’ of classical times. At the same time, however, scholars also began to test and extend this knowledge. The emergent nation states of Europe developed competitive interests in world exploration and the development of trade. Such expansion, which was to take the English language west to America and east to India, was supported by scientific developments such as the discovery of magnetism and hence the invention of the compass improvements in cartography and —perhaps the most important scientific revolution of them all —the new theories of astronomy and the movement of the Earth in relation to the planets and stars, developed by Copernicus (1473-1543).England was one of the first countries where scientists adopted and publicised Copernican ideas with enthusiasm. Some of these scholars, including two with interests in language —John Wallis and John Wilkins — helped found the Royal Society in 1660 in order to promote empirical scientific research.Across Europe similar academies and societies arose, creating new national traditions of science. In the initial stages of the scientific revolution, most publications in the national languages were popular works, encyclopaedias, educational textbooks and translations. Original science was not done in English until the second half of the 17th century. For example, Newton published his mathematical treatise, known as the Principia, in Latin, but published his later work on the properties of light — Opticks — in English.There were several reasons why original science continued to be written in Latin. The first was simply a matter of audience. Latinwas suitable for an international audience of scholars, whereas English reached a socially wider, but more local, audience. Hence, popular science was written in English.A second reason for writing in Latin may, perversely, have been a concern for secrecy. Open publication had dangers in putting into the public domain preliminary ideas which had not yet been fully exploited by their ‘author’. This growing concern about intellectual property rights was a feature of the period — it reflected both the humanist notion of the individual, rational scientist who invents and discovers through private intellectual labour, and the growing connection between original science and commercial exploitation. There was something of a social distinction between ‘scholars and gentlemen’ who understood Latin, and men of trade who lacked a classical education. And in the mid-17th century it was common practice for mathematicians to keep their discoveries and proofs secret, by writing them in cipher, in obscure languages, or in private messages deposited in a sealed box with the Royal Society. Some scientists might have felt more comfortable with Latin precisely because its audience, though international, was socially restricted. Doctors clung the most keenly to Latin as an ‘insider language’.A third reason why the writing of original science in English was delayed may have been to do with the linguistic inadequacy of English in the early modern period. English was not well equipped to deal with scientific argument. First it lacked the necessary technical vocabulary. Second, it lacked the grammatical resources required to represent the world in an objective and impersonal way, and to discuss the relations, such as cause and effect, that might hold between complex and hypothetical entities.Fortunately, several members of the Royal Society possessed an interest in Language and became engaged in various linguistic projects. Although a proposal in 1664 to establish a committee for improving the English language came to little, the society’s members did a great deal to foster the publication of science in English and to encourage the development of a suitable writing style. Many members of the Royal Society also published monographs in English. One of the first was by Robert Hooke, the society’s first curator of experiments, who described his experiments with microscopes in Micrographia (1665). This work is largely narrative in style, based on a transcript of oral demonstrations and lectures.In 1665 a new scientific journal, Philosophical Transactions, was inaugurated. Perhaps the first international English-language scientific journal, it encouraged a new genre of scientific writing, that of short, focused accounts of particular experiments.The 17th century was thus a formative period in the establishment of scientific English. In the following century much of this momentum was lost as German established itself as the leading European language of science. It is estimated that by the end of the 18th century 401 German scientific journals had been established as opposed to 96 in France and 50 in England. However, in the 19th century scientific English again enjoyed substantial lexical growth as the industrial revolution created the need for new technical vocabulary, and new, specialized, professional societies were instituted to promote and publish in the new disciplines.lingua franca: a language which is used for communication between groups of people who speak different languages Questions 28-34Complete the summary.Choose NO MORE THAN TWO WORDS from the passage for each answer.Write your answers in boxes 28-34 on your answer sheet.In Europe, modern science emerged at the same time as the nation state. At first, the scientific language of choice remained 28…………… . It allowed scientists to communicate with other socially privileged thinkers while protecting their work from unwanted exploitation. Sometimes the desire to protect ideas seems to have been stronger than the desire to communicate them, particularly in the case of mathematicians and 29…………… . In Britain, moreover, scientists worried that English had neither the 30…………… nor the 31………… to e xpress their ideas. This situation only changed after 1660 when scientists associated with the 32………… set about developing English. An early scientific journal fostered a new kind of writing based on short descriptions of specific experiments. Although English was then overtaken by 33……… , it developed again in the 19th century as a direct result of the 34……………….Questions 35-37Do the following statements agree with the information given in Reading Passage 3?In boxes 35-37 on your answer sheet, writeTRUE if the statement agrees with the informationFALSE if the statement contradicts the informationNOT GIVEN if there is no information on this35 There was strong competition between scientists in Renaissance Europe.36 The most important scientific development of the Renaissance period was the discovery of magnetism.37 In 17th-century Britain, leading thinkers combined their interest in science with an interest in how to express ideas.Questions 38-40Complete the table.Choose NO MORE THAN TWO WORDS from the passage for each answer.Write your answers in boxes 38-40 on your answer sheet.Science written in the first half of the 17th centuryLanguage used Latin EnglishType of science Original 38…………Examples 39………… EncyclopaediasTarget audience International scholars 40…………, but socially wider剑桥雅思阅读5原文参考译文(test2)BAKELITE The birth of modern plastics酚醛塑料——现代塑料的诞生In 1907, Leo Hendrick Baekeland, a Belgian scientist working in New York, discovered and patented a revolutionary new synthetic mater ial. His invention, which he named ‘Bakelite,’ was of enormous technological importance, and effectively launched the modern plastics industry.1907年，比利时科学家Leo Hendrick Baekeland在纽约工作时发现了一种全新的合成材料，并申请了专利。

丙稀晴－丁二烯－苯乙烯（ABS工程塑料）ABS钢模注铸材料特性：在低温下也能保持很好的抗压强度硬度高、机械强度高抗磨损性好、比重轻相对热量指数高达80c在高温下也能保持很好的尺寸稳定性防火、工艺简单光泽度好、易于上色，相对其他热塑性塑料来说成本较低更多信息：htttp://，htttp://典型用途电子消费品、玩具、环保商品、汽车仪表板、门板、户外护栅。

HP惠普打印机生产商：HP惠普设汁商：ZIBA design丙烯腈—丁二烯—苯乙烯(ABS)是一种热塑性塑料合成聚合物树脂，它的平衡性能很好，能被裁剪以适合特殊需求。

它的主要物理特性是：坚硬、牢固。

树脂等级的ASS能像人造橡胶(或橡胶)一样具有弯曲性能。

其中，聚丁二烯提供很好的抗压强度，非结晶苯乙烯热塑性塑料使ABS的加IT艺更为简单(在模具中更易流动)，而丙烯腈则增加了ABS的牢度、硬度与抗腐蚀性。

有效控制这3种成分使设计师能根据最终产品的需要设计其弹性程度。

可能也正因为这一点，ABS能广泛地应用于家用产品与白色产品之中。

尽管它不像其他工程聚合物那样坚韧，但它能有效控制成本。

最为廉价的塑料－聚丙烯（PP）注铸材料特性：透明度和颜色的多种选择,低密度、抗热性强,良好的硬度、牢度和强度平衡性,加工方式简单而灵活,优秀的抗化学物质性更多信息：htttp://典型用途:家具、包装、照明设备、食物包装、桌垫、文件夹、便签纸盒生产商：Emsdetten公司设计商：Emsdetten公司设计工作并不仅限于创造美丽的形状和完善的功能，而常常是在避免大规模生产的同时寻找降低单品价格和加工成本的方法。

简单地说就是要寻找一种产品，它既适合大规模生产；利用规模生产降低单件成本，同时又无需的满足大规模生产而进行高额投资和高量产出。

最为廉价的塑料－聚丙烯（PP）注铸材料特性：透明度和颜色的多种选择,低密度、抗热性强,良好的硬度、牢度和强度平衡性,加工方式简单而灵活,优秀的抗化学物质性更多信息：htttp://，htttp://典型用途:家具、包装、照明设备、食物包装、桌垫、文件夹、便签纸盒生产商：美国Zyliss AG公司设汁商：IDEO 公司使用三聚氰胺作为外带午餐盒的材料，但这并不是最省钱的选择。

2Chemical resistancePage General information regarding chemical resistance--Introduction4 --Instructions for the use of the chemical resistance list4 List of chemical resistanceChemical resistance73Chemical resistanceGeneral information regarding chemical resistance IntroductionPlastic materials are now widely used in pipeline construction.Pipes made from plastics are used not only for drinking water,water for general use and waste water,but also for the conveyance of aggressive liquids and gases.Expensive pipe materials such as lined metal,ceramic or glass,have largely been replaced by plastic pipes.It is,however,important that the most suitable plastic material is selected for each application. The Chemical Resistance List in this section serves as a useful guide in this respect.The list is periodically revised to include the latest findings.It contains all the plastics and elastomers in the GF product range which can come into direct contact with the media.The information is based on experiments,immersion and, when available,on data from tests which include temperature and pressure as stress factors.The results achieved in immersion experiments cannot be applied without reservation to pipes under stress,i.e.internal pressure,as the factor stress corrosion cracking is often not taken into consideration.In certain cases it can be of advantage to test the suitability under the planned working conditions.The tests referred to have been carried out partly by GF and partly by the Internal Standardisation Organisation(ISO)or national standards organisations.Pure chemicals were used for the tests.If a mixture of chemicals is to be conveyed in practice,this may affect the chemical resistance of the plastic.It is possible in special cases to carry out appropriate tests with the specific mixture.Suitable test equipment is available at GF for this purpose,which we regard as part of our service to the customer.We are always willing to give individual advice at any time.In this connection it is worth mentioning that GF already possesses information concerning the behaviour towards plastics of a number of chemicals or mixtures of chemicals which are not yet included in this list.Instructions for the use of the chemical resistance list GeneralFollowing the assertions outlined in the introduction the attached list should be regarded as a valuable tool for finding the most suitable material for a given application. Note:The list has been compiled based on ideal and mostly simplified conditions of laboratory testing;real life and field applications are subjected to working conditions that might be defined by more complex factors. Consequently any statement quoted in our chemical resistance list should be regarded as a guiding value.In particular,we would like to emphasize that such a list-by nature- cannot supply the following information:ÏAll relevant details of the respective experiment thathas been the source for a given set of dataÏPossible influence of dynamic effectsÏLong-term effectsÏPossible influence due to the method of processing, the thermal history as well as the exact formulation of the respective samplesÏBehaviour of mixtures of different media or effects based on discontinuous serviceÏ(Detailed)characterisation of the corrosion phenomenon/deterioration observedÏDerivation of the max.applicable service pressure ÏConsideration of all chemicalsContacting your GF representative Thus,if it comes to material decisions and there is aneed for selecting the proper polymer(grade),please do not hesitate to contact GF;based on decades of practical experience with polymer piping systems applied in industry and chemical engineering,GF has acquired an outstanding knowledge in:ÏPractical field testing,case studiesÏTheoretical background(corrosion science,polymer formulations,possible influences of processing,etc.)ÏRelevant literature Apart from that,GF is a very active member in a global network for all aspects of corrosion regarding polymers; all this enables us to support the individual enquiries of our customers efficiently.However,we cannot exclude situations where the stock of available data will not completely answer a customer s enquiry.In such cases,a simple laboratory test installation under field test conditions is strongly recommended.4ClassificationThe customary classifications:Ïresistant Ïconditionallyresistant andÏnot recommended are depicted by the signs:+,0and -,which allowsimple presentation and application.These classifications aredefined as:Resistant:+Within the acceptable limits of pressure and temperature the material is unaffected or only insignificantly affected.Conditionally resistant:0The medium can attack the material or cause swelling.Restrictions must be made as regards pressure and/or temperature,taking the expected service life into account.The service life of the installation can be noticeably shortened.Further consultations with GF are recommended in any case.Not recommended:-The material cannot be used with the medium at all,or only under special conditions.Solvent cement joints with Tangit/DytexSolvent cementjointson ABS,PVC-U or PVC-C madewith Tangit cement are generally as resistant as thematerial of the piping system itself.The use of Dytex solvent cement isrecommended forcement jointing of PVC-U or PVC-C in connection with the following acids:Medium Upto%concentrationSulphuric acid e 70%H 2SO 4Chromic-sulphuric acid mixture e 70%H 2SO 4+5%K 2Cr 2O 7/Na 2Cr 2O 1Chromic acid d 10%CrO 3Hydrochloric acid e 25%HClNitric acid e 20%HNO 3Sodium hypochlorite (potassium hypochlorite)e 6%NaOCl Hydrogen peroxide e 5%H 2O 2Hydrofluoric acid e 0%HF For all the media mentioned above in lower concentrations,Tangit solvent cement should be used.Due to the effects of these acids on the pipe material,we recommend using pipes with a pressure rating PN 16.For the expected life time and compressive strength,please contact your GF representative.Attention !Usually the allowable pressure must be decreased by one pressure rating (thus PN16to PN10).When using Dytex in PVC-C piping construction with the above mentioned acids,the pressure and temperature requirements for PVC-U must be adhered to.Because Dytex is not gap-filling,a special cement jointing procedure is required and is described in the chapter on jointing technology.Fusion jointsIn the case of PE,PP and PVDF (SYGEF®)heat fusionjoints have practically the same chemical resistance asthe respective material.In conjunction with media which could cause stress cracking,the fused joints can besubjected to an increased risk due to residual stress from the jointing process.In such cases a professionally executed weldingis absolutely necessary.The sensitivity against tension fracture formation can be reduced substantially by a thermal retreatment (tempering).Sealing materialsDepending upon the working conditions and the stressinvolved,the life span of the sealing materials can differfrom that of thepipelinematerial.Seals in PTFE,which is not included in this list,are resistant to all the chemicals listed.The greater permeability of PTFEshould,however,be considered.Under certain working conditions,for example when conveying highly aggressive media such as hydrochloric acid,thismaterial characteristic must be taken into account.General summary and limits of applications 5The following table includes all the materials contained in the GF product range,and their abbreviations.The summary gives preliminary information regarding the general behaviour of the materials and the temperature limits.Abbreviation MaterialRemarks Maximum permissible temperature Constant Short term PTFEPolytetrafluoro-ethylene (e.g.Teflon®)Resistant to all chemicals in this list 250°C 300°C NBRNitrile Rubber Good resistance to oil and petrol.Unsuitable for oxidising media 90°C 120°C EPDM Ehtylene Propylene Rubber Good resistance to ozone and weather.Especially suitable for aggressive chemicals.Unsuitable for oils and fats 90°C 120°C CRChloroprene Rubber (e.g.Neoprene®)Chemical resistance very similar to that of PVC-U and between that of Nitrile and Butyl Rubber 80°C 110°C FPM FFKM Fluorine Rubber (e.g.Viton®,Kalrez®)Has best chemical resistance to solvents of all elastomers 150°C 200°C CSM Chlorine sulphonyl Polyethylene (e.g.Hypalon®)Chemical resistance similar to that of EPDM 100°C 140°CCompressible mediaWhen defining allowable operating conditions,special care is required in choosing chemically resistant piping and sealing materials when transporting compressible operating media (gases)or solutions of gases in fluids which have low boiling points (high vapour pressures)through plastic piping systems.Suitable materials for compressible media are those that under standard conditions and at low temperatures do not tend toward brittle fractures owing to their ductility.Such materials include polyethylene (PE)and acrylonitrile-butadiene-styrene (ABS).All other raw materials such as polypropylene (PP-H),polyvinyl chloride (PVC-U/-C)or polyvinyliden fluoride (PVDF)are to be limited to d 0.1bar with respect to the operating pressure of gases.Higher pressures are possible if secondary containment piping systems are used (for environmental protection,brittle effects,gas shocks,intoxication)For low boiling point fluids,such as liquid gas or solutions of gases in liquids,for example,hydrochloric acid,the associated vapour pressure of the media has to be taken into account.Furthermore,outgassing (due to changes in the media composition)or vaporisation (due to an inadmissible,high pressure increase)are to be prevented by relevant limitation of the operating temperature or by preventing the vapour pressure from exceeding the operational pressure.It is important to point out that,in such cases of leakage,the sudden escape of large gas or vapour volumes is to be considered a dangerous condition.Relatively high flow velocities must be assumed when transporting humid gases (aerosols)or following pressure drops in plasticpiping systems carrying fluids having high vapour pressures.These can cause the development of high levels of electrostatic charge.Such a condition exhibits an additional source of danger if flammable media or mixtures which can explode when mixed with air are involved.NoteThe data are provided as is and there is no warranty or representation,neither express nor implied,that they are free from errors.We shall not be liable for any damages of any kind that may result from the use of this data.The successful operation of valves does not only depend on the chemical resistance of their materials and the seals,but a multiplicity of further factors are to be considered.Therefore it is not possible to transfer these data without restrictions also to the operation of valves made of same materials and/or material combinations.This document serves only to provide technical information.We refer to our General Sales Terms.Subject to change without notice.6List of chemical resistance Aggressive mediaChemical resistanceMediumFormula B o i l i n g p o i n t °C Concentration T e m p e r a t u r e °C P V C -U P V C -C A B S P E P P -H P V D F E P D M F P M N B R C RC S M Acetaldehyde CH 3-CHO 40%,aqueous 20O --++-++-++solution 40-+O O +++60O O O O O O 80O O --O 100-120140Acetaldehyde CH 3-CHO 21technically pure 20---+O -+O --O 40O -O --60-80100120140Acetic acid CH 3COOH 50%,aqueous 20++-++++O -O O 40++++O 60O +++80O 100O 120140Acetic acid CH 3COOH 118technically pure,20O --++++--O O glacial 40-++O O 60O O -80-100120140Acetic acid (CH 3-CO)2O 139technically pure 20---++-O ---+anhydride 40O O 6080100120140Acetic acid CH 3COOC 2H 57720---++++O O O O ethylester 406080100120140Acetic acid (CH 2)2-CH-(CH 2)2-CO 2H 117technically pure 20---++++---+isobutyl ester 406080100120140Acetone CH 3-CO-CH 3up to 10%,20--O ++O +O -+O aqueous 40++O +O O O 60++O +--O 80100120140Acetone CH 3-CO-CH 356technically pure 20---++-+---O 40+++O 60+++O801001201407Aggressive mediaChemical resistanceMediumFormula B o i l i n g p o i n t °C Concentration T e m p e r a t u r e °C P V C -U P V C -C A B S P EP P -H P V D F E P D M F P M N B R C R C S M Acetonitrile CH 3CN 82100%20---O O -O -O O O 406080100120140Acetophenone CH 3-CO-C 6H 5202100%20---O O -+---+406080100120140Acrylic acid CH 2=CHCOOCH 380technically pure 20---O -O O methyl ester 406080100120140Acrylicethyl CH 2=COOC 2H 5100technically pure 20---O -O O --O O 406080100120140Acrylonitrile CH 2=CH-CN 77technically pure 20---++-+O -+O 40+O +O +O 60+O -+-80100120140Adipic acid HOOC-(CH 2)4-COOH Fp.,saturated,20++-++++++++153aqueous 40++++++++++60-+++++++++80+++100120140Allyl alcohol H 2C=CH-CH 2-OH 9796%20O O -+++O +O +40-+++-+-+60+O O ++80-+-100120140Aluminium salts,AlCl 3,Al(NO 3)3,saturated 20++aqueous,Al(OH)3,Al(SO 4)340++inorganic 60++80+100120140Ammonia NH 3-33gaseous,20+--++++++++technically pure 40++++O 60++++80+100-1201408Aggressive mediaChemical resistanceMediumFormula B o i l i n g p o i n t °C Concentration T e m p e r a t u r e °C P V C -U P V C -C A B S P EP P -H P V D F E P D M F P M N B R C R C S M Ammonium CH 3COONH 4aqueous,all 20++O ++++++++acetate 40+++++++O ++60O ++++++O 80+++O 100++120140Ammonium (NH 4)2S 2O 820+++O +++O ++persulphate 40+O +60O O +80O +100+120140Amonium salts,saturated 20++++++++++aqueous,40++++++++++inorganic 60++++++++++80+++100+120140Amyl acetate CH 3(CH 2)4-COOCH 3141technically pure 20---+O +O ----40+O O 60+-O 80100120140Amyl alcohol CH 3(CH 2)3-CH 2-OH 137technically pure 20+--++++O ++O 40+++++++60O ++++++80++100+120O 140Aniline C 6H 5NH 2182technically pure 20---++++O ---40O +O +O 60O -+O 80100120140Antimony SbCl 390%,aqueous 20++-+++++-++trichloride 40+++++60++++80100120140Aqua regia HNO 3+HCl mixing ratio 20++---O -O --O 40O 6080100120140Arsenic acid H 3AsO 480%,aqueous 20+++++++++++40+++++++++++60O ++++++++++80+++++O ++100++120+1409Aggressive mediaChemical resistanceMediumFormula B o i l i n g p o i n t °C Concentration T e m p e r a t u r e °C P V C -U P V C -C A B S P E P P -H P V D F E P D M F P M N B R C R C S M Barium salts,saturated 20+++++++++++aqueous,40++++++++inorganic 60+++++++80++++100++120140Beer usual 20++++++++++commercial 406080100120140Benzaldehyde C 6H 5-CHO 180saturated,20---+++++O --aqueous 40+O O ++60O -O +80100120140Benzene C 6H 680technically pure 20---O O +-+O --40O -O 60-80100120140Benzene sulfonic C 6H 5SO 3H technically pure 20+++++++acid 40+++++60O O +O 80+100+120140Benzine C 5H 12to C 12H 2680-free of lead and 20++-+O +-++-O (Gasoline)130aromatic 40++++++-compounds 6080100120140Benzoic acid C 6H 5-COOH Fp.,aqueous,all 20+++++++++++12240++++++++60O +++++80O +++100++O 120+140Benzyl alcohol C 6H 5-CH 2-OH 206technically pure 20O --+++++-+O 40+++++60O O O O +80-100120140Beryllium salts,20++++++++++aqueous,40+++++++inorganic 60+++++++80++++100+12014010Medium Formula B o i l i n g p o i n Concentration T e m p e r a t u r P V C -UP V C -CA B SP EP P -HP V D FE P D MF P MN B RC RC S M BoraxNa 2B 4O 7aqueous,all20+++++++++++40+++++++++++60O ++++++++O 80++++100++120140Boric acid H 3BO 3all,aqueous20+++++++++++40+++++++++++60O ++++++++++80+++++100+++120+140Brine,containing NaCl-Cl 2depressurised 20++-+O+O +O OO chlorinewith GFK-40+++reinforcing up to 60++O95°C 80+100120140Bromine water Br-H 2Osaturated,20+O ---+-+---aqueous406080100120140Butadiene H 2C=CH-CH=CH 2-4technically pure 20++-O O +-+O --406080100120140Butane C 4H 100technically pure 20++++++-+O OO 406080100120140Butanediol HO-(CH 2)4-OH 230aqueous,10%20++-+++++O +40O ++++++-+60++++++80100120140Butanol C 4H 9OH 117technically pure 20+--++++++++40+++++O +++60O +O ++-+O+80-+100O 120140Butyl acetate CH 3COO(CH)3CH 2CH 2CH 3126technically pure 20---+O++O -O O 40O ----60-80100120140Medium FormulaB o i l i n g p o i n ConcentrationT e m p e r a t u r P V C -UP V C -CA B SP EP P -HP V D FE P D MF P MN B RC RC S M Butyl phenol,(CH 3)3C-C 6H 4-OH237technically pure20O O -O ++-O ---p-tertiary40--+60+80+100120140Butylene glycol HO-CH 2-CH=CH-CH 2-OH 235technically pure20+++++++-+O 40++++++++-60O +++++O+80+100120140Butylene liquid C 4H 851technically pure 20+--+O +++O 406080100120140Butyric acid CH 3-CH 2-CH 2-COOH 163technically pure 20++-+++O O -OO 406080100120140Cadmium salts,d saturated acid20++++++aqueous,40++++++inorganic60++++++80++100120140Caesium salts,d Saturated acid20++++++++++aqueous,40+++++++inorganic60+++++++80++++100+120140Calcium acetate (CH 5COO)2Ca saturated20++++++++++40+++++++60+++++++80++100120140Calcium Ca(OH)2100saturated,20+O++O +++++hydroxidaqueous40+++-+++++60+++++O ++80++++100++120140Calcium lactate (CH 3COO)2Ca saturated20++++++++++40+++++++60+++++80+++100+120140Medium Formula B o i l i n g p o i n Concentration T e m p e r a t u r P V C -UP V C -CA B SP EP P -HP V D FE P D MF P MN B RC RC S M Calcium salts,d Saturated acid20+++++++++++aqueous,40++++++++inorganic60+++++++80++++100+120140Carbon dioxide CO 2technically pure,20++++++++++anhydrous40++++++++++60++++++++++80++++++100+120140CarbonCCl 477technically pure 20-----+-+---tetrachloride406080100120140Carbonic acid H 2CO 320++++++++++40+++++++60+++++++80+++++100120140Caro's acid H 2SO 520+O -+406080100120140Caustic potash KOH 13150%,aqueous20+O++-+-O O+solution 40++++-O (potassium 60O +O+O hydroxide)80O-100120140Caustic soda NaOH 50%,aqueous20+O ++-+-O -+solution40+-+++60++O+80100120140Chloric acid HClO 310%,aqueous20++-+-+++--+40+++++++60O ++++80100120140Chloric acid HClO 320%,aqueous20++-O -+O +--+40++O++60O ++80100120140Medium Formula B o i l i n g p o i n Concentration T e m p e r a t u r P V C -UP V C -CA B SP EP P -HP V D FE P D MF P MN B RC RC S M ChlorineCl 2moist,97%,20-+-----+--O gaseous40+60+80+100120140Chlorine Cl 2liquid,technically 20-----+-O ---pure,as double 40pipe system6080100120140Chlorine Cl 2anhydrous,20---O -+O +--O technically pure,40O +as double pipe 60-+system80+100O 120140Chlorine water Cl 2-H 2O saturated20++OO O OO +-O-40++O60O O 80-100120140Chloroacetic ClCH 2COOH 50%,aqueous 20+--+++O ---O acid,mono40+++O 60O O -80100120140Chloroacetic ClCH 2COOH 188technically pure 20+--+++O ---O acid,mono40+++O60O O O80100120140Chlorobenzene C 6H 5Cl 132technically pure 20---O O+----O 40+60O 80-100120140Chloroethanol ClCH 2-CH 2OH 129technically pure 20---+++O ---O 40++O 60++O 80-100120140Chlorosulphonic ClSO 3H 158technically pure 20O ----O -----acid40-6080100120140Medium Formula B o i l i n g p o i n Concentration T e m p e r a t u r P V C -UP V C -CA B SP EP P -HP V D FE P D MF P MN B RC RC S M Chromic acidCrO 3H 2Oall,aqueous20O O -O O++--O 40O ++O 60+OO 80O 100O 120140Chromic acid CrO 350g 20++---+O +--O +sulphuric acid H 2SO 415g 40+++O+O +water H 2O 35g 60O OO80100120140Chromium (II)-d Saturated acid20++salts,aqueous,40++inorganic60++80+100+120140Compressed air,20---+O+-++++containing oil40++60+80100120140Copper salts,d Saturated acid20+++++++++++aqueous 40+++++++++++inorganic60O ++++++O +O 80++++100+120140Cresol HO-C 6H 4-CH 3cold saturated,20O --+++O+O -O aqueous40+OO +O60OO 80O100120140Crotonic CH 3-CH=CH-CHO 102technically pure 20---++++++++aldehyde40O 60-80100120140Cyclohexane C 6H 1281technically pure 20---+++-++--40++60++80+100120140Cyclohexanol C 6H 12O 161technically pure20++-+++-+O ++40+++++60+++OO 80OO 100-120140Medium Formula B o i l i n g p o i n ConcentrationT e m p e r a t u r P V C -UP V C -CA B SP EP P -HP V D FE P D MF P MN B RC RC S M CyclohexanoneC 6H 10O155technically pure20---+++O ----40O O O 60O O -80100120140Dextrine (C 6H 10O 5)nusual20+++++++++++commercial40++++++++++60++++++++++80++100+120+140Di isobutyl [(CH 3)2CHCH 2]2CO 124technically pure 20---+++O ----ketone40O O OO6080100120140Dibrombenzene C 6H 5Br 2d Saturated acid 20---O O +O +---406080100120140Dibuthyl ether C 4H 9OC 4H 9142technically pure 20---O O +-++-O 406080100120140Dibutyl phthalate C 6H 4(COOC 4H 9)2340technically pure 20---+++O O ---40O O +60O O O80100120140Dichloroacetic Cl 2CHCOOH 50%,aqueous 20+--++++O -+O acid40+++O+O 60O O O+-80100120140Dichloroacetic Cl 2CHCOOH 194technically pure 20+--++++O --O acid40+++O+-60O O O+-80100120140Dichloroacetic Cl 2CHCOOCH 3143technically pure 20---++O+---+acid methyl 40++++ester60++OO80100120140Medium Formula B o i l i n g p o i n ConcentrationT e m p e r a t u r P V C -UP V C -CA B SP EP P -HP V D FE P D MF P MN B RC RC S M DichlorobenzeneC 6H 4Cl 2180technically pure20---O O +O +O OO 406080100120140Dichloroethylene ClCH=CHCl 60technically pure 20-----+-O ---40+6080100120140Diesel oil20++-+O+-++OO 40+++++-6080100120140Diethyl ether H 5C 2-O-C 2H 53520-----------406080100120140Diethylamine (C 2H 5)2NH 56technically pure 20--+++O ----40O 60-80100120140Dimethyl (CH 3)2CHNO 153technically pure 20---++-O -O ++formamide40++60O +80100120140Dimethylamine (CH 3)2NH 7technically pure 20---+--O ----406080100120140Dioxane C 4H 8O 2101technically pure 20---+O -O -O --40+O 60+O 80-100120140Ethanolamine C 2H 7NO 20---++O +O O OO406080100120140Medium Formula B o i l i n g p o i n ConcentrationT e m p e r a t u r P V C -UP V C -CA B SP EP P -HP V D FE P D MF P MN B RC RC S M Ethyl alcohol CH 3-CH 2-OH78technically pure,20+O -+++++O ++(Ethnause)96%40+++O +O 60O ++-+O80+100120140Ethyl benzene C 6H 5-CH 2CH 3136technically pure 20---O O O -+---406080100120140Ethyl chloride C 2H 5Cl 12technically pure 20---O O O -O ---(G)406080100120140Ethyl ether CH 3CH 2-O-CH 2CH 335technically pure 20---+O +-----406080100120140Ethylene diamine H 2N-CH 2-CH 2-NH 2117technically pure 20O --++O +O ++O 40++O O O O O 60++-----80100120140Ethylene glycol HO-CH 2-CH 2-OH 198<50%20+OO ++++++++40+O++++++++60++++++O O+80+++OO 100+120+140Ethylene glycol HO-CH 2-CH 2-OH 198technically pure 20+O -++++++++40+++++++++60++++++O O+80+++OO 100+120+140Ethylenediamine-C 10H 16N 2O 820++++tetraacetic acid 40(EDTA)6080100120140Fluorine F 2technically pure20-----------406080100120140Medium Formula B o i l i n g p o i n Concentration T e m p e r a t u r P V C -UP V C -CA B SP EP P -HP V D FE P D MF P MN B RC RC S M Fluorosilicic acidH 2SiF 632%,aqueous20++++++OO O +40+++++--O 60+O +++-80+100+120140Formaldehyde HCHO 40%,aqueous20++++++++++40++++++++++60++++O OO 80+100120140Formamide HCONH 2210technically pure 20---+++O ++40++60++80100120140Formic acid HCOOH d 25%20++++++40++++++60++++++80++100120140Formic acid HCOOHup to 50%,20+-O+++++-++aqueous40++++++++60O +O+OO O+80+-O 100+120140Formic acid HCOOH 101technically pure 20+--+++++-++40O +O ++O +60-+-+O -+80+OO 100+120140Frigen 12(Freon CCl 2F 2-30technically pure 20+----OO O O +O 12)406080100120140Fuel oil20++-+O +-++OO 40++-+++-6080100120140Furfuryl alcohol C 5H 6O 2171technically pure20---+++O --OO40++60+OO 80-100120140Medium Formula B o i l i n g p o i n Concentration T e m p e r a t u r P V C -UP V C -CA B SP EP P -HP V D FE P D MF P MN B RC RC S M Gelatinall,aqueous20+++++++++++40+++++++++++60+++++80+100120140Glucose C 6H 12O 6Fp.,all,aqueous 20++++++++++14840++++++++++60O +++++++++80++++++++100++120140Glycerol HO-CH 2-CH(OH)-CH 2OH 290technically pure20++++++++++40+++++O ++++60+++++OO +++80+++-O++100++O O 120+140Glycin NH 2-CH 2-COOHFp.,10%,aqueous 20++++++++++23340+++++++O+O 60++80+100120140Glycolic acid HO-CH 2-COOHFp.,37%,aqueous 20+-+++++++8040++60++80+100+120140Heptane C 7H 1698technically pure20++-+O+-++-O 40++++++-6080100120140Hexane C 6H 1469technically pure20++-+O+-++-O 40++++++-6080100120140Hydrazine H 2N-NH 2-H 2O 113aqueous 20+--++-+O --+hydrate40++60++80100120140Hydrochloric HClup to 30%,20+++++++--+acidaqueous40+++O +++O 60+++O +O O-80+-+100+120140Medium Formula B o i l i n g p o i n Concentration T e m p e r a t u r P V C -UP V C -CA B SP EP P -HP V D FE P D MF P MN B RC RC S M Hydrochloric HCl38%,aqueous20++-+O+++--+acid40++++O +60+++80O+100+120140Hydrocyanic HCN 26technically pure20++-+++++O O +acid40+++++O O --O 60O ++++80+100120140Hydrofluoric acid HF 40%20+--+++-+--+40O +++++60O O ++OO 80+100+120140Hydrogen H 2-25technically pure 20+++++++++++340+++++++++++60+++++++++++80+++++++100-+++120140Hydrogen HCl-85technically pure,20++-+++++O O O chloridegaseous40+++++++--O 60O ++++++-80O++100+120140Hydrogen H 2O 210530%,aqueous 20++-++OO +--+peroxide406080100120140Hydrogen H 2O 213990%,aqueous 20+--O -O --O peroxide406080100120140Hydrogen H 2Ssaturated,20+++++++-++sulphideaqueous40+++++-+--+60O +++++O 80+O-100+120140Hydrogen H 2S technically pure20++++++++O +sulphide40+++++-+O -O 60++O ++O -O 80+--100+120140Medium Formula B o i l i n g p o i n Concentration T e m p e r a t u r P V C -UP V C -CA B SP EP P -HP V D FE P D MF P MN B RC RC S M HydroquinoneC 6H 4(OH)230%20+++++40++++60++80+100120140Iodine-potassium I-KI 20+--+++++OO iodide solution 40(Lugol's solution)6080100120140Iron salts,d Saturated acid20+++++++++++aqueous,40+++++++inorganic60+++++++80+++++100++120140Isooctane (CH 3)3-C-CH 2-CH-(CH 3)299technically pure 20++-++++++O 406080100120140Isopropyl alcohol (CH 3)2-CH-OH 82technically pure 20+-++++++++(ESC)40+++++60O O O+80O100120140Isopropyl ether (CH 3)2-CH-O-CH-(CH 3)268technically pure 20---O O +O ----406080100120140Lactic acid CH 3CHOHCOOH 10%,aqueous20++++++++--O 40O +O ++++O O 60-+-++O O O O 80++O -O100-120140Lead acetate Pb(CH 3COO)2aqueous,20+++++++++++saturated40+++++++++++60+++++++++++80++100+120140Lead salts,d Saturated acid20++++++++++aqueous,40+++++++inorganic60+++++++80+++100+120140。

塑料问题英语作文Title: The Plastic Predicament: A Global Call for ActionIn the intricate tapestry of modern life, plastics have woven themselves into every fabric, from the mundane to the extraordinary. They areubiquitous, versatile, and, unfortunately, increasingly problematic. The plastic predicament—a crisis that spans oceans, landfills, and the very health of our planet—demands urgent attention and concerted global action.The Rise of PlasticsPlastics, first synthesized in the early 20th century, revolutionizedindustries and lifestyles. Lightweight, durable, and cheap to produce,they quickly replaced traditional materials in packaging, construction, transportation, electronics, and countless other sectors. However, this convenience came at a steep environmental cost. Single-use plastics,particularly those designed for short-term usage and immediate disposal, have proliferated exponentially, creating a mountain of waste that the planet struggles to contain.The Environmental Toll1.Ocean Pollution: Plastic waste, much of which escapes recycling systems, ends up in our oceans. It breaks down into microplastics, which areingested by marine life, disrupting food chains and potentially harming human health through the seafood we consume.2.3.Landfill Overflow: Landfills are filling up rapidly with non-biodegradable plastics, taking up valuable space and leaching harmful chemicals into soil and groundwater.4.5.Wildlife Impacts: Animals from all ecosystems are at risk, from seaturtles mistaking plastic bags for jellyfish to birds getting entangled in discarded fishing nets.6.7.Climate Change: The production of plastics, especially from fossil fuels, contributes to greenhouse gas emissions, exacerbating global warming. 8.Global Response: A Call for Action1.Reduce, Reuse, Recycle: The first line of defense is to reduce ourreliance on single-use plastics and promote reusable alternatives.Governments, businesses, and individuals must work together toimplement policies and practices that prioritize circular economyprinciples.2.3.Innovation and Research: Investing in research and development of biodegradable and sustainable plastic alternatives is crucial. Scientists are exploring materials derived from natural sources like plants andalgae, which can decompose safely in the environment.4.5.Improved Waste Management: Strengthening waste collection, sorting, and recycling systems is vital. This includes investing in infrastructure and raising public awareness about proper disposal methods.6.7.International Cooperation: The plastic crisis is global, requiringinternational cooperation and agreements. The United NationsEnvironment Programme (UNEP) and other international bodies should facilitate dialogues and set ambitious targets for reducing plasticpollution.8.9.Corporate Responsibility: Corporations must take responsibility for the full lifecycle of their products, including end-of-life management. They should adopt sustainable packaging practices and invest in circulardesign principles.10.11.Consumer Awareness and Behavior Change: Educating the public about the impact of plastic waste and encouraging behavior change is essential.Simple acts like carrying reusable bags, using refillable containers, and avoiding disposable plastics can make a significant difference.12.ConclusionThe plastic predicament is a complex challenge that requires amultifaceted approach involving governments, businesses, andindividuals worldwide. By adopting sustainable practices, investing ininnovation, and fostering international cooperation, we can mitigate the damage already done and pave the way for a greener, more resilientfuture. The time to act is now, before the tide of plastic wasteoverwhelms us all.。

关于材料塑料的英语作文Title: The Role and Impact of Plastics in Modern Society。

Plastics, ubiquitous in our modern lives, play a multifaceted role in various sectors, ranging from packaging and construction to healthcare and transportation. However, their widespread use also raises concernsregarding environmental sustainability and human health. In this essay, we will delve into the significance, benefits, challenges, and potential solutions associated with plastics.Firstly, let us acknowledge the significance of plastics. These versatile materials have revolutionized industries worldwide due to their durability, flexibility, and cost-effectiveness. In the realm of packaging, plastics offer lightweight and durable alternatives to traditional materials like glass and metal, reducing transportation costs and energy consumption. Moreover, plastics play acrucial role in modern medicine, facilitating advancementsin drug delivery systems, medical devices, and prosthetics, thereby enhancing healthcare outcomes and patient comfort.Despite their undeniable benefits, plastics pose significant challenges, primarily concerning environmental sustainability. The durability of plastics, a boon in many applications, becomes a curse when it comes to disposal. Single-use plastics, in particular, contribute to pollution, clogging waterways, harming marine life, and degrading ecosystems. Moreover, the production of plastics relies heavily on non-renewable fossil fuels, exacerbating climate change and resource depletion.To address these challenges, various strategies have been proposed. Recycling represents a promising approach to mitigate the environmental impact of plastics. By diverting plastics from landfills and incinerators, recycling conserves resources, reduces energy consumption, and minimizes pollution. However, challenges such as limited recycling infrastructure, contamination of recyclable materials, and low consumer awareness hinder theeffectiveness of recycling initiatives.In addition to recycling, innovations in material science offer potential solutions to the plastic crisis. Biodegradable plastics, derived from renewable sources such as plant-based polymers, present a more sustainable alternative to traditional plastics. These bioplastics decompose naturally, reducing the burden on landfills and ecosystems. Furthermore, advances in polymer chemistry enable the development of recyclable plastics with enhanced properties, such as improved durability and biodegradability.Education and awareness also play a vital role in addressing the plastic problem. By promoting eco-friendly habits, such as reducing plastic consumption, reusing products, and properly disposing of waste, individuals can contribute to a more sustainable future. Moreover, advocating for policy changes, such as plastic bans or extended producer responsibility schemes, can incentivize businesses to adopt more environmentally friendly practices and products.In conclusion, plastics represent a double-edged sword in modern society, offering unparalleled convenience and versatility while posing significant environmental and health risks. To ensure a sustainable future, concerted efforts are needed to address the challenges associated with plastics through recycling, innovation, education, and policy intervention. By embracing these solutions, we can harness the benefits of plastics while minimizing their negative impacts on the planet and future generations.。

大学英语精读第四册Unit one: Big Bucks the Easy Way Introductory RemarksIn the United States of America Family background or personal influence plays a much less important role than in many other societies. Anyone who wants to become successful has to rely mainly on his own efforts. That’s why many American parents encourage their children to do part-time jobs while studying in college or even in high school. This is of great benefit to the young people not only financially but also in the development and formation of character, for in the process of work, they can learn a lot of things which are impossible for them to acquire (= get / obtain) from their textbooks at school.In this story, for instance, the two college sons have to develop management skills quickly in order to get their work done; they have to learn cooperation, team work, efficiency and business ethics (理念)in order to meet the real world’s deadlines. And the two youngest sons have also to learn that “you are never done with books”, because books teach us knowledge and theories which are as important as, if not more important than, practical experience.Written in a humorous style (幽默的风格), the story also tells us as well as all those youngsters that there is no easy way to earn a lot of money in the United States. You have to learn quickly and work hard before you can get your share of money.PrefacePatterns:be unaware of (sth) = be unconscious of (sth)be unaware + that clause = be unconscious +that clause Pattern:involve oneself in / with / into sth = be involved in / with/ intotempt (=induce) sb into doing sth诱惑某人做某事Compare: advertisement / advertisingadvertisement / commercialsPattern:promise sb. to do sthprobably = maybe = perhapsCompare :too … to(否定)only/but/simply/never too …to (强调肯定)1)This text is too difficult to learn.2)This text is simply/but/only/never too difficult to learn.Big Bucks the Easy Way轻轻松松赚大钱buck (American slang = money): ten bucks (=dollars); in the bucks (手头有钱)Lines 1 – 14look into = investigate: look into (=investigate) the matter Pattern: suggest sth to sbavoid (vt.): keep away from (避开; 避免)Pattern: avoid doing sth. (Right); avoid to do sth. (Wrong) dignity (庄严; 尊严); indignity = in + dignityplastics (n.) (塑料); plastic (adj.)塑料的hang –hanged – hanged (vt.)吊死；绞死e.g.: The murder was sentenced to be hanged.hang – hung – hung (vi. & vt.)悬挂；垂下e.g.: I plan to hang some pictures in my new house. message: note; informationtext message手机短信leisurely (adj.):(moving, acting, or done) without haste; unhurried 从容的; 不慌不忙的lucrative (adj.): profitableleisurely, lucrative work: work that brings in a lot of money and can be done with ease 能轻松赚钱的工作I can live with(=put up with / endure)it (=indignity). panhandle:(AmE) beg, esp. on the streetembarrass sb. = make sb. feel embarrassed 使人感到难为情magazine-delivery thing 投递杂志的事settle (=accommodate) oneself in some placeLines 15 – 29enthuse (vi.): show enthusiasm非常兴奋；兴高采烈enthuse (vi.) --- enthusiasm (n.) --- enthusiastic (adj.)inquire = ask: Pattern:inquire / ask sth of sb.super (colloq.): wonderful; splendid; excellentsnap (vt.): say (sth.) sharply 厉声地说“Super!” she snapped, “Just super!…”: The verb “snapped” makes it clear that she was saying this in an ironical tone. As a matter of fact, her day was just awful.truck (AmE) = lorry (BrE)pull up: come to a stop; bring to a stope.g.: John was walking along the street when suddenly a car pulled up beside him.Montgomery Wards; Sears; Roebucks:They are mail-order business companies 从事邮递业务的公司…it will be four thousand of something:…it will be four thousand advertising inserts for some other department store or companyPattern: be responsible (to sb.) for sth.Compare:responsibility --- obligation --- liabilityFill in each of the blanks with the proper word:Your _____ is to sign the contract between the two companies. Each company must carry out the signed contract for its ____, andany party has to take its _____ if it fails to implement the contract Patterns: Sb. is to blame for sth (Formal)Sb is blamed for sth; blame sb for / on sth (Informal)…it turned out(prove / come to be clear) 插入语hand-deliver (vt.) = deliver by hand派人直接送advertising inserts用于广告作用插在报纸或杂志中的广告插页…are included with(=be inserted between / be put between)…Patterns:1.promise to do sth2. promise sb to do sth3. promise sb for sth(a) piece of cake: a colloquial phr ase “sth can be done easily”Lines 30 – 50six hundred (bucks = dollars)echo (vt.): repeat (the word, feelings , etc. of sb.) 附和; 重复e.g.: The little boy echoes everything his brother says. Patterns:1. inform sb of sth. 2. inform sb + that clauseAnd we do the job in two hours. (note: not using “after”) porch (AmE) = veranda (BrE) 门廊even as (= just at the time when ) we speak 引导让步状语load 装--- unload卸carrying armloads (n.) of sth: carrying armful of sth…all this指这么多广告to get (系动词) busy = to start to workurgent message紧急留言unnaturally high: extraordinarily / extremely highquaver (vi.): (of the voice or a sound) shake; tremble颤抖truckloads of ad inserts几卡车的广告插页dime: coin of U.S. and Canada, worth of ten centsdime store: 廉价商品店drugstore: 杂货店；药店grocery :食品店greengrocery: 蔬菜店whole magazine sections整本杂志那么厚cram (vt.)把…塞满; 装满wall-to-wall(方式状语): 类似的表达方式face-to-face; shoulder-to-shoulderstack = pile 堆in stacks = pile and pile; in pilestake one each of the eleven inserts从十一中插页中各取一份slip a rubber band around them套上橡皮筋slide into塞进takeout restaurant 外卖餐馆Her voice kept rising, as if working its way out of the range of the human ear. :Her voice kept rising as if (her voice was) rising to such a pitch that it could no longer be heard by the human ear.keep doing sth持续做某事as if:后可接现在分词He paused as if expecting me to speak. work one?s way费力前进; 努力获得range范围; out of the range of超过…范围Lines 51 – 65Pattern: had better do sth; had better not do sth.as … as one can= as … as possiblee.g.: Please come here as soon as you can. = Please come here as soon as possibleGot a lunch date. = I have got an appointment for lunch.I had had a marvelous steak, but knew better by now than to say so.我吃的牛排好极了，但这次学乖了，还是不说为妙know better than to do很明智不去做…e.g.: As a college student, you should know better than to waste your time like that.Some sort of (= something like) sour fisheel: (long, snake-like fish) 鳗；鳝a couple of = a few 两三个；几个；assembly line装配线；流水作业“movement” = some progress or advanceencouraging --- discouragingPattern:encourage sb. to do sth.Pattern: be at sth:从事于; 在状态中e.g.: They are still at work (at rest).Compare: roof --- ceilingdent (n.)凹下的地方make a dent in 使凹下去(即减少);此处意为减少一点;有所进展re-: again; once more使…再生; 增加re produce --- re print --- re tell --- re thinkLines 66 – 80get…out of…: 从…中得到get the best out of …: 从…中得到最大利益…one does not get the best out of employees by …: one does not get the greatest possible amount of work out of his employees by …bodily harm体罚obtaining an audience with跟…通话son No. 1: the older sonPatterns: threaten (vt.)1.Nuclear weapons threaten the peace and security of theworld.2.The robber threatened me with a gun.3.He threatens to make the photo public.bonus: reward cut into (=reduce) our profitunless: if notPattern: enable sb. to do sth. = make sb. able to do sth. Compare: on time --- in timeIf they don?t =If they don?t make all the deliveries on time There will be (is) no +动名词= it will be (is) impossible to do 意为“不可能”1.There is no getting along with him.跟他是无法相处的。

试卷主标题姓名：__________ 班级：__________学号：__________一、选择题（共15题）1、—Hi, I’m Peter. Are you new here? I haven’t seen you around?—Hello, Peter. I’m Bob. I just ________ on Monday.A．start B．have startedC．started D．had started2、（2018·北京）_________ we don’t stop climate change, many animals and plants in the world will be gone.A．Although B．WhileC．If D．Until3、（2018·北京）_________ along the old Silk Road is an interesting and rewarding experienceA．Travel B．TravelingC．Having traveled D．Traveled4、 Susan had quit her well-paid job and _________ as a volunteer in the neighborhood when I visited her last year.A．is working B．was workingC．has worked D．had worked5、（2018·北京）She and her family bicycle to work, _________ helps them keep fit.A．which B．whoC．as D．that6、（2018·北京）During the Mid-Autumn Festival, family members often gather together _________ a meal, admire the moon and enjoy moon cakes.A．share B．to shareC．having shared D．shared7、China’s high-speed railways _________ from 9,000 to 25,000 kilometers in the past few years.A．are growing B．have grownC．will grow D．had grown8、 In any unsafe situation, simply ________ the button and a highly-trained agent will get you the help you need.A．press B．to pressC．pressing D．pressed9、 A rescue worker risked his life saving two tourists who ________ in the mountains for two days.A．are trapping B．have been trappedC．were trapping D．had been trapped10、（2018· 北京）Ordinary soap, _________ correctly, can deal with bacteria effectively.A．used B．to useC．using D．use11、（2018· 北京）Without his support, we wouldn’t be _________ we are now.A．how B．whenC．where D．why12、(2018·北京) In today’s information age, the loss of data _________ cause serious problems for a company.A．need B．shouldC．can D．must13、（2018·北京）They might have found a better hotel if they _________ a few more kilometers.A．drove B．would driveC．were to drive D．had driven14、（2018·北京）—Good morning, Mr. Lee’s office.—Good morning. I’d like to make an appointment _________ next Wednesday afternoon.A．for B．onC．in D．at15、（2018· 北京）This is _________ my father has taught me—to always face difficulties and hope for the best.A．how B．whichC．that D．what二、完型填空（共1题）1、 The Homeless HeroFor many, finding an unattended wallet filled with £400 in cash would be a source （来源）of temptation（诱惑）. But the 16 would no doubt be greater if you were living on the streets with little food and money. All of this makes the actions of the homeless Tom Smith 17 more remarkable.After spotting a 18 on the front seat inside a parked car with its window down, he stood guard in the rain for about two hours waiting for the 19 to return.After hours in the cold and wet, he 20 inside and pulled the wallet out hoping to find some ID so he could contact（联系）the driver, onlyto 21 it contained £400 in notes, with another £50 in spare change beside it.He then took the wallet to a nearby police station after 22 a note behind to let the owner know it was safe. When the car’s owner John Anderson and his colleague Carol Lawrence returned to the car—which was itself worth £35, 000—in Glasgow city centre, they were 23 to find two policemen standing next to it. The policemen told them what Mr. Smith did and that the wallet was 24 .The pair were later able to thank Mr. Smith for his 25 .Mr. Anderson said：＂I couldn’t believe that the guy never took a penny. To think he is sleeping on the streets tonight 26 he could have stolen the money and paid for a place to stay in. This guy has nothing and27 he didn’t take the wallet for himself；he thought aboutothers 28 . It’s unbelievable. It just proves thereare 29 guys out there.＂Mr. Smith’s act 30 much of the public’s attention. He also won praise from social media users after Mr. Anderson 31 about the act of kindness on Facebook.Now Mr. Anderson has set up an online campaign to 32 money for Mr. Smith and other homeless people in the area, which by yesterday had received ￡8,000. ＂I think the faith that everyone has shown 33 him has touched him. People have been approaching him in the street; he’s had job 34 and all sorts,＂ Mr. Anderson commented.For Mr. Smith, this is a possible life-changing 35 . The story once again tells us that one good turn deserves another.16．A．hope B．aim C．urge D．effort17．A．still B．even C．ever D．once18．A．wallet B．bag C．box D．parcel19．A．partner B．colleague C．owner D．policeman20．A．turned B．hid C．stepped D．reached21．A．discover B．collect C．check D．believe22．A．taking B．leaving C．reading D．writing23．A．satisfied B．excited C．amused D．shocked24．A．safe B．missing C．found D．seen25．A．service B．support C．kindness D．encouragement26．A．when B．if C．where D．because27．A．rather B．yet C．already D．just28．A．too B．though C．again D．instead29．A．honest B．polite C．rich D．generous30．A．gave B．paid C．cast D．drew31．A．learned B．posted C．cared D．heard32．A．borrow B．raise C．save D．earn33．A．of B．at C．for D．in34．A．details B．changes C．offers D．applications35．A．lesson B．adventure C．chance D．challenge三、阅读理解（共5题）1、 My First Marathon（马拉松）A month before my first marathon, one of my ankles was injured and this meant not running for two weeks, leaving me only two weeks to train. Yet, I was determined to go ahead.I remember back to my 7th year in school. In my first P.E. class, the teacher required us to run laps and then hit a softball. I didn’t do either well. He later informed me that I was ＂not athletic＂.The idea that I was ＂not athletic＂ stuck with me for years. When I started running in my 30s, I realized running was a battle against myself, not about competition or whether or not I was athletic. It was all about the battle against my own body and mind. A test of wills!The night before my marathon, I dreamt t hat I couldn’t even find the finish line.I woke up sweating and nervous, but ready to prove something to myself.Shortly after crossing the start line, my shoe laces(鞋带) became untied. So I stopped to readjust. Not the start I wanted!At mile 3, I passed a sign: ＂GO FOR IT, RUNNERS!＂By mile 17, I became out of breath and the once injured ankle hurt badly. Despite the pain, I stayed the course walking a bit and then running again.By mile 21, I was starving!As I approached mile 23, I could see my wife waving a sign. She is my biggest fan. She never minded the alarm clock sounding at 4 a.m. or questioned my expenses on running.I was one of the final runners to finish. But I finished! And I got a medal. In fact, I got the same medal as the one that the guy who came in first place had.zxxkDetermined to be myself, move forward, free of shame and worldly labels(世俗标签), I can now call myself a ＂marathon winner＂.36．A month before the marathon, the author ____________.A．was well trained B．felt scaredC．made up his mind to run D．lost hope37．Why did the author mention the P.E. class in his 7th year?A．To acknowledge the support of his teacher.B．To amuse the readers with a funny story.C．To show he was not talented in sports.D．To share a precious memory.38．How was the author’s first marathon?A．He made it. B．He quit halfway.C．He got the first prize. D．He walked to the end.39．What does the story mainly tell us?A．A man owes his success to his family support.B．A winner is one with a great effort of will.C．Failure is the mother of success.D．One is never too old to learn.2、 Find Your Adventure at the Space and Aviation(航空) CenterIf you’re looking for a unique adventure, the Space and Aviation Center (SAC) is the place to be. The Center offers programs designed to challenge and inspire with hands-on tasks and lots of fun.More than 750,000 have graduated from SAC, with many seeking employment in engineering, aviation, education, medicine and a wide variety of other professions. They come to camp, wanting to know what it is like to be an astronaut or a pilot, and they leave with real-world applications for what they’re studying in the classroom.For the trainees, the programs also offer a great way to earn merit badges(荣誉徽章). At Space Camp, trainees can earn their Space Exploration badge as they buildand fire model rockets, learn about space tasks and try simulated(模拟) flying to space with the crew from all over the world. The Aviation Challenge program gives trainees the chance to earn their Aviation badge. They learn the principles of flight and test their operating skills in the cockpit(驾驶舱) of a variety of flight simulators. Trainees also get a good start on their Wilderness Survival badge as they learn about water- and land-survival through designed tasks and their search and rescue of ＂downed＂ pilot.With all the programs, teamwork is key as trainees learn the importance of leadership and being part of a bigger task.All this fun is available for ages 9 to 18. Families can enjoy the experience together, too, with Family Camp programs for families with children as young as 7.Stay an hour or stay a week — there is something here for everyone!For more details, please visit us online at .40．Why do people come to SAC?A．To experience adventures.B．To look for jobs in aviation.C．To get a degree in engineering.D．To learn more about medicine.41．To earn a Space Exploration badge, a trainee needs to .A．fly to spaceB．get an Aviation badge firstC．study the principles of flightD．build and fire model rockets42．What is the most important for trainees?A．Leadership. B．Team spirit.C．Task planning. D．Survival skills.3、 Plastic-Eating WormsHumans produce more than 300 million tons of plastic every year. Almost half of that winds up in landfills(垃圾填埋场), and up to 12 million tons pollute the oceans. So far there is no effective way to get rid of it, but a new study suggests an answer may lie in the stomachs of some hungry worms.Researchers in Spain and England recently found that the worms of the greater wax moth can break down polyethylene, which accounts for 40% of plastics. The team left 100 wax worms on a commercial polyethylene shopping bag for 12 hours, and the worms consumed and broke down about 92 milligrams, or almost 3% of it. To confirm that the worms’ chewing alone was not responsible for the polyethylene breakdown, the researchers made some worms into paste(糊状物) and applied it to plastic films. 14 hours later the films had lost 13% of their mass —apparently broken down by enzymes (酶) from the worms’ stomachs. Their findings were published in Current Biology in 2017.Federica Bertocchini, co-author of the study, says the worms’ ability to break down their everyday food — beeswax — also allows them to break down plastic. ＂Wax is a complex mixture, but the basic bond in polyethylene, the carbon-carbon bond, is there as well, ＂she explains, ＂The wax worm evolved a method or system to break this bond. ＂Jennifer DeBruyn, a microbiologist at the University of Tennessee, who was not involved in the study, says it is not surprising that such worms can break down polyethylene. But compared with previous studies, she finds the speed of breaking down in this one exciting. The next step, DeBruyn says, will be to identify the cause of the breakdown. Is it an enzyme produced by the worm itself or by its gut microbes(肠道微生物)?Bertocchini agrees and hopes her team’s findings might one day help employ the enzyme to break down plastics in landfills. But she expects using the chemical in some kind of industrial process — not simply ＂millions of worms thrown on top of the plastic.＂43．What can we learn about the worms in the study?A．They take plastics as their everyday food.B．They are newly evolved creatures.C．They can consume plastics.D．They wind up in landfills.44．According to Jennifer DeBruyn, the next step of the study is to .A．identify other means of the breakdownB．find out the source of the enzymeC．confirm the research findingsD．increase the breakdown speed45．It can be inferred from the last paragraph that the chemical might .A．help to raise wormsB．help make plastic bagsC．be used to clean the oceansD．be produced in factories in future46．What is the main purpose of the passage?A．To explain a study method on worms.B．To introduce the diet of a special worm.C．To present a way to break down plastics.D．To propose new means to keep eco-balance.4、 Preparing Cities for Robot CarsThe possibility of self-driving robot c ars has often seemed like a futurist’s dream, years away from materializing in the real world. Well, the future is apparently now. The California Department of Motor Vehicles began giving permits in April for companies to test truly self-driving cars on public roads. The state also cleared the way for companies to sell or rent out self-driving cars, and for companies to operate driverless taxi services. California, it should be noted, isn’t leading the way here. Companies have been testing their vehicles in cities across the country. It’s hard to predict when driverless cars will be everywhere on our roads. But however long it takes, the technology has the potential to change our transportation systems and our cities, for better or for worse, depending on how the transformation is regulated.While much of the debate so far has been focused on the safety of driverless cars(and rightfully so), policymakers also should be talking about how self-driving vehiclescan help reduce traffic jams, cut emissions(排放) and offer more convenient, affordable mobility options. The arrival of driverless vehicles is a chance to make sure that those vehicles are environmentally friendly and more shared.Do we want to copy — or even worsen — the traffic of today with driverless cars? Imagine a future where most adults own individual self-driving vehicles. They tolerate long, slow journeys to and from work on packed highways because they can work, entertain themselves or sleep on the ride, which encourages urban spread. They take their driverless car to an appointment and set the empty vehicle to circle the building to avoid paying for parking. Instead of walking a few blocks to pick up a child or the dry cleaning, they send the self-driving minibus. The convenience even leads fewer people to take public transport — an unwelcome side effect researchers have already found in ride-hailing(叫车) services.A study from the University of California at Davis suggested that replacing petrol-powered private cars worldwide with electric, self-driving and shared systems could reduce carbon emissions from transportation 80% and cut the cost of transportation infrastructure(基础设施) and operations 40% by 2050. Fewer emissions and cheaper travel sound pretty appealing. The first commercially available driverless cars will almost certainly be fielded by ride-hailing services, considering the cost of self-driving technology as well as liability and maintenance issues(责任与维护问题). But driverless car ownership could increase as the prices drop and more people become comfortable with the technology.Policymakers should start thinking now about how to make sure the appearance of driverless vehicles doesn’t extend the worst aspects of the car-controlled transportation system we have today. The coming technological advancement presents a chance for cities and states to develop transportation systems designed to move more people, and more affordably. The car of the future is coming. We just have to plan for it.47．According to the author, attention should be paid to how driverless cars can __________.A．help deal with transportation-related problemsB．provide better services to customersC．cause damage to our environmentD．make some people lose jobs48．As for driverless cars, what is the author’s major concern?A．Safety. B．Side effects.C．Affordability. D．Management.49．What does the underlined word ＂fielded＂ in Paragraph 4 probably mean?A．Employed. B．Replaced.C．Shared. D．Reduced.50．What is the author’s attitude t o the future of self-driving cars?A．Doubtful. B．Positive.C．Disapproving. D．Sympathetic.5、 Why Do We Get Angry?Anger seems simple when we are feeling it, but the causes of anger are various. Knowing these causes can make us examine our behavior, and correct bad habits. The main reasons we get angry are triggering（触发）events, personality traits（特征）, and our assessment of situations. 51．Triggering events for anger are so many that to describe them all would take hundreds of pages. However, here are some examples: being cut off in traffic, a deadline approaching, experiencing physical pain, and much more. 52． The reason why someone is triggered by something and others are not is often due to one’s personal history and psychological traits.Each person, no matter who they are, has psychological imbalances. People who have personality traits that connect with competitiveness and low upset tolerance are much more likely to get angry. 53． Also, sometimes pre-anger does not have to do with a lasting condition, but rather a temporary state before a triggering event has occurred.54．Sometimes even routine occurrences become sources of pre-anger, or anger itself. Sometimes ignorance and negative (消极的) outlooks on situations can create anger.55．However, anger can easily turn violent, and it is best to know the reasons for anger to appear in order to prevent its presence. With these main reasons in mind, we can evaluate our level of anger throughout the day and prevent cases of outbursts by comprehending the reasons for our feelings.A．Our attitude and viewpoint on situations can create anger within us as well.B．But some types of situations can help us to get rid of the occurrence of anger.C．Anger is rarely looked upon as a beneficial character trait, and is usually advised to reduce it.D．Anger is a particularly strong feeling and maybe people think that they have reasons to feel angry.E.Having these personality traits implies the pre-anger state, where anger is in the background of your mind.F.Understanding these reasons will control our own anger if we are willing to evaluate ourselves with a critical eye.G.Not everyone acts the same in response to events, and that is why what triggers one person may or may not trigger another.四、作文（共2题）1、（2018·北京）假设你是红星中学高三学生李华，你的英国朋友Jim在给你的邮件中提到他对中国文化感兴趣，计划明年来北京上大学。

Material01. Plastics, Man’s Most Useful Material1)The word ‘plastic’ comes from the Greek word ‘plastikos’ and is used to describe somethingwhich can be easily shaped. You will see what a suitable name this is for ‘plastics’.2)No other material in the history of the world has been used for so many different purposes. 5But what special qualities do plastics have? The lightness of plastics is one of their mostvaluable qualities. Think how easy it is to lift plastic furniture! Think, too, how lightplastic containers are! A delivery man can carry many more plastic containers thancontainers made of wood or metal or glass.3)It is quite extraordinary1how many different kinds and qualities of plastics there are. They 10can be harder than wood or softer than rubber. They can be made so strong that they willlast almost for ever, or so thin and cheap that they can be thrown away after only being usedonce. They can be made as clear as glass or completely black. They can be made anycolour you like to choose. They can even be made to look like wood or leather or stone.4)Plastics were at first based on coal and wood. But today they are nearly based on mineral 15oil2, that is to say, oil which is found underground. Mineral oil, of course, is of no use toman until it has been cleaned and separated into its different commercial products -- oil forships and trains, petrol for cars and aeroplanes, machine oil3 of all kinds. This cleaning andseparating is known as ‘refining’ and is done in big factories called ‘refineries4’.5)For a long time scientists could find little use for the material which remained after the oil 20had been refined. Then one day scientists made the exciting discovery that it could beturned into plastics.6)The manufacture of plastics demands an immense amount of heavy machinery as well as aknowledge of science. Today nearly all modern plastics are manufactured by the world’sgreat oil refineries and chemical works5. The refineries and chemical works produce many 25different kinds of raw plastics. These are then sent to the tens of thousands of factories allover the world which make plastic goods.7)Machinery for making plastic goods is quite different from the machinery used formanufacturing articles of wood or metal or other natural materials. For raw plastics are firstsoftened by heat and then pressed into moulds. It is the moulds which give plastic objects 30their shape. These moulds can be of any shape or size. And the same mould can be usedover and over again. In fact one mould can produce many thousands of articles before itwears out. It is this which makes plastics goods so cheap.1 extraordinary: 非常的，特别的。

工业产品常用材料介绍1、金属材质介绍Information about metal material2、塑料材质介绍Information about new plastics material3、玻璃材质介绍Information about glass material4、陶瓷材质介绍Information about ceramics material金属材质介绍Information about metal material不锈钢——不生锈的革命材料特性：卫生保健、防腐蚀、可进行精细表面处理、刚性高、可通过各种加工工艺成型、较难进行冷加工。

典型用途：奥氏体不锈钢主要应用于家居用品、工业管道以及建筑结构中；马氏体不锈钢主要用于制作刀具和涡轮刀片；铁素体不锈钢具有防腐蚀性，主要应用在耐久使用的洗衣机以及锅炉零部件中；复合式不锈钢具有更强的防腐蚀性能，所以经常应用于侵蚀性环境。

铬——高光洁度的后处理材料特性：光洁度非常高、优良的防腐蚀性能、坚硬耐用、易于清洗、摩擦系数低。

典型用途：铬最为常见的存在形式是作为合金元素用于不锈钢中，来增强不锈钢的硬度。

装饰性镀铬是许多汽车元件的镀层材料，包括车门把手以及缓冲器等，除此之外，铬还应用于自行车零部件、浴室水龙头以及家具、厨房用具、餐具等。

硬质镀铬更多的用于工业领域，包括作业控制块中的随机存储器、喷气机发动机元件、塑料模具以及减震器等。

黑色镀铬主要用于乐器装饰以及太阳能利用方面。

铝——现代材料材料特性：柔韧可塑、易于制成合金、高强度-重量比、出色的防腐蚀性、易导电导热、可回收。

市面上铝产品的产量已经远远超过了其他有色金属产品的总和。

典型用途：交通工具骨架、飞行器零部件、厨房用具、包装以及家具。

铝也经常被用以加固一些大型建筑结构，比如伦敦皮卡迪利广场上的爱神雕像，以及纽约克莱斯勒汽车大厦的顶部等，都曾用铝质加固材料。

镁合金——超薄美学设计材料特性：轻量化的结构、刚性高且耐冲击、优良的耐腐蚀性、良好的热传导性和电磁遮蔽、良好的不可燃性、耐热性较差、易回收。

环保塑料袋Plastics高英语作文•相关推荐环保塑料袋Plastics高英语作文（通用19篇）在日常的学习、工作、生活中，大家或多或少都会接触过作文吧，作文一定要做到主题集中，围绕同一主题作深入阐述，切忌东拉西扯，主题涣散甚至无主题。

还是对作文一筹莫展吗？下面是小编为大家整理的环保塑料袋Plastics高英语作文，欢迎大家分享。

环保塑料袋Plastics高英语作文篇1Plastics are man-made materials with new properties. They are anywhere in our daily lives. They are very light but they can hold heavy things. That’s why they’re so popular all around the world.Plastics have found their widest applications. They can be used for almost everything from food coverings to automobiles bodies. Thousands of different products are now made entirely or partially from plastics. Of course more and more plastics will be made in the future.However, because the plastics are not rusting, they have negative effects on the global environment. The plastics bags are not easily to break down. If you’re burning them, they gas will pollute the environment. If you throw them into the river, the fish will die because they’re contain toxi c. If you bury them, the land will not grow any crops. Most of the plastics are white, thus people call it “white pollution”.In order to protect the environment, we should not use plastics if we could. We should use some cloths bags instead. Only in this way, we can have a good environment.塑料袋是人们用新型材料制作的物品。

有关塑料环保的新闻报道英语作文英文回答：Plastic pollution has become a global environmental crisis, with devastating consequences for marine life and the health of our planet. According to the United Nations Environment Programme (UNEP), over 8 million tons of plastic end up in our oceans annually, where it can take centuries to decompose. This has led to widespread concern about the need to reduce plastic usage and promote more sustainable alternatives.In recent years, there have been numerous news reports highlighting the problem of plastic pollution and its impact on the environment. One notable example is an article published in the journal "Nature" in 2019, which estimated that by 2050, there could be more plastic than fish in the oceans. Another widely cited study, published in the journal "Science Advances" in 2020, found that plastic pollution could potentially kill more than 1million seabirds and 100,000 marine mammals each year.The media has also played a crucial role in raising awareness about the issue. Documentaries such as the BBC's "Blue Planet II" and National Geographic's "Planet or Plastic?" have showcased the devastating effects of plastic pollution on marine ecosystems, prompting many viewers to rethink their own plastic consumption habits. News reports have also highlighted the efforts of environmentalactivists and scientists working to reduce the use of single-use plastics and develop more sustainable alternatives.In response to the growing public awareness about plastic pollution, governments and businesses around the world have begun to take action. Many countries have implemented bans or restrictions on certain single-use plastics, such as plastic bags, straws, and cutlery. Some governments have also invested in waste management systems to improve the collection and recycling of plastic materials. Additionally, businesses are increasingly adopting sustainable packaging practices and exploringalternative materials to reduce their reliance on plastic.Despite these efforts, much more needs to be done to address the problem of plastic pollution. Individuals can play a significant role by reducing their own plastic consumption, supporting businesses that prioritize sustainability, and advocating for policies that promotethe use of sustainable alternatives. By working together,we can create a more sustainable future for our planet and its oceans.中文回答：塑料污染已经成为了一场全球环境危机，对海洋生物和我们星球的健康造成了毁灭性的后果。

Autodesk®Moldflow® Insight Plastics made perfect.1Autodesk® Moldflow® Insight software, part ofthe Autodesk® solution for Digital Prototyping,provides injection molding simulation tools foruse on digital prototypes. Providing in-depthvalidation and optimization of plastic parts andassociated injection molds, Autodesk MoldflowInsight software helps study the injection moldingprocesses in use today. Used by some of thetop manufacturers in the automotive, consumerelectronics, medical, and packaging industries,Autodesk Moldflow Insight software helps toreduce the need for costly mold rework andphysical prototypes, minimize delays associatedwith removing molds from production, and getinnovative products to market faster.Autodesk Moldflow Insight Product LineAutodesk is dedicated to providing a wide rangeof injection molding simulation tools to help CAEanalysts, designers, engineers, mold makers, andmolding professionals create accurate digitalprototypes and bring better products to marketat less cost.Validation and Optimization of Plastic PartsWith the use of plastic parts on the rise in almost every industry, and the pressure to reduce costs and cut time to market, the need for simulation tools that provide deep insight into the plastic injection molding process has neverbeen greater.12Hot Runner SystemsModel hot runner system components and set up sequential valve gates to help eliminate weld lines and control the packing phase.Plastic Flow SimulationSimulate the flow of melted plastic to help optimize part and mold designs, reduce potential part defects, and improve the molding process.Part DefectsDetermine potential part defects, such as weld lines, air traps, and sink marks, and then rework designs to help avoid these problems.Thermoplastic FillingSimulate the filling phase of the thermoplasticinjection molding process to help predict the flow of melted plastic and fill mold cavities uniformly; avoid short shots; and eliminate, minimize, or reposition weld lines and air traps.Thermoplastic PackingOptimize packing profiles and visualize magnitude and distribution of volumetric shrinkage to help minimize part warpage and reduce defects, such as sink marks.Validate and optimize plastic parts, injection molds, and theinjection molding process.Feed System SimulationModel and optimize hot and cold runner systems and gating configurations. Improve part surfaces, minimize part warpage, and reduce cycle times.Gate LocationIdentify up to 10 gate locations simultaneously. Minimize injection pressure and exclude specific areas when determining gate location.Runner Design WizardCreate feed systems based on inputs for layout, size, and type of components, such as sprue, runners, and gates.Balancing RunnersBalance runner systems of single-cavity, multicavity, and family mold layouts so parts fill simultaneously,reducing stress levels and volume of material.Mold Cooling SimulationImprove cooling system efficiency, minimize part warpage, achieve smooth surfaces, and reduce cycle times.Cooling Component ModelingAnalyze the mold’s cooling system efficiency. Model cooling circuits, baffles, bubblers, and mold inserts and bases.Cooling System AnalysisOptimize mold and cooling circuit designs to help achieve uniform part cooling, minimize cycle times, reduce part warpage, and decrease manufacturing costs.WarpagePredict warpage resulting from process-inducedstresses. Identify where warpage might occurand optimize part and mold design, materialchoice, and processing parameters to help controlpart deformation.Core Shift ControlMinimize the movement of mold cores by determin-ing ideal processing conditions for injectionpressure, packing profile, and gate locations.Fiber OrientationControl fiber orientation within plastics to helpreduce part shrinkage and warpage across themolded part.CAE Data ExchangeValidate and optimize plastic part designs usingtools to exchange data with structural simulationsoftware. CAE data exchange is available withAutodesk® Algor® Simulation, ANSYS®, andAbaqus® structural simulation software to accountfor the effects of processing on the performanceof fiber-filled, injection-molded plastic parts whensubjected to service loading.Rapid Heat Cycle MoldingSet up variable mold surface temperature profilesto both maintain warmer temperatures duringfilling to achieve smooth surfaces, and also reducetemperatures in the packing and cooling phases tohelp freeze parts and decrease cycle times.Shrinkage & Warpage SimulationEvaluate part and mold designs to help controlshrinkage and warpage.ShrinkageMeet part tolerances by predicting part shrinkagebased on processing parameters and grade-specificmaterial data.34Thermoset Flow SimulationSimulate thermoset injection molding, RIM/SRIM, resin transfer molding, and rubber compound injection molding.Reactive Injection MoldingPredict how molds will fill with or without fiber-reinforced pre-forms. Help avoid short shots due to pre-gelation of resin, and identify air traps and problematic weld lines. Balance runner systems, select molding machine size, and evaluate thermoset materials.Microchip EncapsulationSimulate encapsulation of semiconductor chips with reactive resins and the interconnectivity of electrical chips. Predict bonding wire deformation within the cavity and shifting of the lead frame due to pressure imbalances.Underfill EncapsulationSimulate flip-chip encapsulation to predictmaterial flow in the cavity between the chip andthe substrate.Leading-Edge Simulation ToolsUse leading-edge simulation tools to solve design challenges.Insert OvermoldingRun an insert overmolding simulation to helpdetermine the impact of mold inserts on melt flow, cooling rate, and part warpage.Two-Shot Sequential OvermoldingSimulate the two-shot sequential overmolding process: one part is filled; the tool opens and indexes to a new position; and a second part is molded over the first.BirefringencePredict optical performance of an injection-molded part by evaluating refractive index changes that result from process-induced stresses. Evaluate multiple materials, processing conditions, and gate and runner designs to help controlbirefringence in the part.Specialized Molding ProcessesSimulate a wide range of plastic molding processes and state-of-the-art process applications.Gas-Assisted Injection MoldingDetermine where to position polymer and gas entrances, how much plastic to inject prior to gas injection, and how to optimize size and placement of gas channels.Co-Injection MoldingVisualize the advancement of skin and core materials in the cavity and view the dynamic relationship between the two materials as filling progresses. Optimize material combinations while maximizing the product's cost-performance ratio.Injection-Compression MoldingSimulate simultaneous or sequential polymer injection and mold compression. Evaluate material candidates, part and mold design,and processing conditions.5CAD Interoperability and MeshingUse tools for native CAD model translation and optimization. Get geometry support for thin-walled parts and thick and solid applications. Select mesh type based on desiredsimulation accuracy and solution time.CAD Solid ModelsImport and mesh solid geometry from Parasolid ®-based CAD systems, Autodesk ® Inventor ® software, CATIA ® V5, Pro/ENGINEER ®, and SolidWorks ®, as well as IGES and STEP universal files.Error Checking and RepairScan imported geometry and automatically fix defects that can occur when translating the model from CAD software.Centerline Import/ExportImport and export feed system and coolingchannel centerlines from and to CAD software to help decrease modeling time and avoid runner and cooling channel modeling errors.Autodesk ® Moldflow ® CAD DoctorCheck, correct, heal, and simplify solid models imported from 3D CAD systems to prepare for simulation.3D SimulationsPerform 3D simulations on complex geometry using a solid, tetrahedral, finite element mesh technique. Ideal for electrical connectors, thick structural components, and geometries with thickness variations.Dual Domain TechnologySimulate solid models of thin-walled parts using Dual Domain™ technology. Work directly from 3D solid CAD models, leading to easier analysis of design iterations.Midplane MeshesGenerate 2D planar surface meshes with assignedthicknesses for thin-walled parts.Results Interpretation & PresentationUse a wide range of tools for model visualization, results evaluation, and presentation.Automatic Reporting ToolsUse the Report Generation Wizard to create web-based reports. Prepare and share simulation results more quickly and easily with customers, vendors, and team members.Microsoft® OfficeExport results and images for use in Microsoft®Word reports and PowerPoint® presentations. Autodesk® Moldflow® Communicator Collaborate with manufacturing personnel, procurement engineers, suppliers, and external customers using Autodesk® Moldflow®Communicator software. The Autodesk Moldflow Communicator results viewer enables you to export results from Autodesk Moldflow software so stakeholders can more easily visualize, quantify, and compare simulation results.Material DataImprove simulation accuracy with precisematerial data.Materials DatabaseUse the built-in materials database of grade-specific information on more than 8,000 plasticmaterials characterized for use in plastic injectionmolding simulation.Autodesk® Moldflow® Plastics LabsGet state-of-the-art plastic material testingservices, expert data-fitting services, and extensivematerial databases.Productivity ToolsUse extensive help to boost productivity.HelpGet help on a results plot, including informationon what to look for and how to correct typicalproblems. Learn more about solver theory,interpreting simulation results, and designingbetter plastic parts and injection molds.Automation and CustomizationAutomate common tasks and customize AutodeskMoldflow software for your organization.API ToolsApplication programming interface (API) toolsexpand the functionality of Autodesk Moldflowsoftware by enabling you to automate commontasks, customize the user interface, work with third-party applications, and help implement corporatestandards and best practices.WorkspacesCustomize the user interface and applicationfeatures for your team. Set up profiles to guide newusers through the simulation process and identifycommon problems. Define other profiles to giveadditional functionality and flexibility to moreexperienced users. Results Evaluation and Productivity ToolsVisualize and evaluate simulation results, and use the automatic reporting tools to share the results with stakeholders. Take advantage of features such as a materials database and customizable workspaces to further boostproductivity.6。

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In recent years,the issue of environmental protection has gained increasing attention globally.Among various types of waste,plastic waste stands out as a significant contributor to environmental pollution.However,it is important to recognize that plastic is a recyclable material,and with proper management,it can be transformed into valuable resources.This essay aims to discuss the recyclability of plastic waste and the importance of recycling efforts.IntroductionPlastic,a versatile and widely used material,has become an indispensable part of modern life.However,the convenience it brings also comes with a cost to the environment. Plastic waste,if not managed properly,can lead to pollution in oceans,harm to wildlife, and the depletion of natural resources.Despite these challenges,plastic is inherently recyclable,offering a sustainable solution to the waste problem.The Recyclability of PlasticPlastic is made from polymers,which are long chains of molecules that can be broken down and reprocessed into new materials.This inherent quality of plastic makes it a prime candidate for recycling.The process of recycling plastic involves several steps:1.Collection:The first step in recycling plastic is to collect and sort it by type.This is crucial as different types of plastics require different recycling processes.2.Cleaning:Once sorted,the plastic is cleaned to remove any contaminants,such as food residues or adhesive labels.3.Shredding:The plastic is then shredded into small pieces,making it easier to process.4.Melting:The shredded plastic is melted down,which allows it to be reshaped into new forms.5.Molding:The molten plastic is then molded into new products,which can range from plastic bottles to furniture.Benefits of Recycling PlasticRecycling plastic offers numerous benefits,both to the environment and the economy:1.Conservation of Resources:By recycling plastic,we can reduce the demand for newraw materials,such as petroleum,which is used to produce plastic from scratch.2.Energy Savings:The process of recycling plastic requires less energy compared to manufacturing new plastic products,thus contributing to energy conservation.3.Reduction of Landfill Waste:Recycling helps to divert plastic waste from landfills, reducing the environmental footprint of waste disposal.4.Economic Opportunities:The recycling industry creates jobs and stimulates economic growth by providing a market for recycled materials.Challenges in Plastic RecyclingDespite the benefits,there are challenges associated with plastic recycling:1.Contamination:If plastics are not properly sorted,they can become contaminated, making the recycling process more difficult or even impossible.2.Public Awareness:Many people are not aware of the importance of recycling or how to recycle correctly,leading to improper disposal of plastic waste.3.Infrastructure:Some areas lack the necessary infrastructure to support effective recycling programs.ConclusionIn conclusion,plastic is a recyclable material with the potential to reduce environmental impact and contribute to a circular economy.By understanding the process of recycling and its benefits,we can encourage more people to participate in recycling efforts.It is essential to address the challenges and improve public awareness and infrastructure to make plastic recycling a more widespread and effective practice.Through collective action,we can turn a problem into a solution,protecting our environment for future generations.。