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Damping Characteristics of Chlorobutyl Rubber/ Poly(ethyl acrylate)/Piezoelectric Ceramic/Carbon Black CompositesZhiyuan Liu,Yanyan Wang,Guangsu Huang,Jinrong WuCollege of Polymer Science and Engineering,State Key Laboratory of Polymer Material Engineering, Sichuan University,Chengdu610065,ChinaReceived7March2007;accepted28July2007DOI10.1002/app.27141Published online7March2008in Wiley InterScience().ABSTRACT:In this study,a new kind of damping com-posite consisting of chlorobutyl rubber,poly(ethyl acry-late),piezoelectric ceramic(PZT),and carbon black(CB) was prepared,and some efforts were made to characterize the damping behavior and explore the damping mecha-nism.The damping behaviors of the composites were mainly decided by the contents of CB and PZT.When an external vibration was exerted on the composites,the me-chanical energy of vibration was transformed into electric energy by PZT;if the resistance was adjusted to a suitable range by the variation of the CB content,the composites could behave as semiconductors:the electric energy could not be transferred to the surface of the material but rather was dissipated as thermal energy.For this system,when the contents of CB and PZT were between10and30vol %,respectively,the volume resistivity was between105 and109.5O cm,and a good damping performance could be achieved.On the basis of the results,a theoretical model is proposed to explain the damping performance of the composites.Ó2008Wiley Periodicals,Inc.J Appl Polym Sci 108:3670–3676,2008Key words:composites;elastomers;fillers;functionaliza-tion of polymers;matrixINTRODUCTIONThe control of vibration and noise pollution has become an urgent task in modern society.For this purpose,developing a new style of damping mate-rial and researching the damping mechanism are strongly required.Currently,polymers are often used as damping materials because of their visco-elasticity,but they also have some disadvantages. First of all,the damping range of homopolymers is generally20–308C because of their narrow glass-tran-sition region,which is not broad enough for practi-cal applications.Second,damping materials derived from polymers often exhibit a strong dependence on the temperature or frequency,and they hardly keep an even damping property in their functional area.A lot of methods,such as polymer blends,interpene-trating networks,and copolymers,1–5have been suc-cessfully developed to broaden the effective damp-ing range of polymers and to modify the depend-ence of damping behaviors on the temperature and frequency.However,there are few results yet that can broaden the transition peaks and at the same time retain a high loss factor.Recently,some studies have been carried out on piezoelectric composite materials6–12and on organic hybrids consisting of polymers and small molecules.13,14As far as organic hybrids are concerned,the weakness of the intermo-lecular hydrogen bond can easily lead to phase sepa-ration during the application process,which limits their usage in long-term service,whereas piezoelec-tric composite materials do not have such a disad-vantage.Piezoelectric ceramic(PZT)is a kind of material that has the ability to transform vibration and noise into electric energy.If PZT is pressed or pulled in a specific direction,a positive electrical charge or a negative one,respectively,will appear on the surfa-ces,and the electrical charge density has a propor-tional relationship with the stress intensity;this is called the piezoelectric effect.However,the hard and crisp properties of PZT limit its applications. Fortunately,Newnham et al.15in1978put forward a novel idea for a piezoelectric composite.According to the approach,PZT andflexible polymers are mixed with each other by certain combination meth-ods to obtain a piezoelectric composite with a certain mass ratio and a certain space distribution to take advantage of the two kinds of materials,which com-pensate each other and have good synthesis proper-ties.As a new kind of damping material,a piezo-electric composite overcomes the weakness that properties of polymers heavily depend on the tem-perature and frequency and avoids the disadvantage that PZT is hard,frail,and not easily processed,pre-serving the advantages of the two materials.Correspondence to:G.Huang(polymer410@). Journal of Applied Polymer Science,Vol.108,3670–3676(2008)Research on the relation between the damping prop-erty and electric resistance shows that a certainmatched electric resistance is necessary for a piezo-electric composite to have a high damping prop-erty.16Therefore,it is possible to control the damp-ing property of piezoelectric composites by changes in the quantity of carbon black(CB).17,18In our previous study,19poly(ethyl acrylate)(PEA)was used to successfully broaden the effective damp-ing region of chlorobutyl rubber(CIIR)to the room-temperature region,but it was found that the loss fac-tor of CIIR/PEA blends was not high enough and,moreover,its dependence on temperature(or fre-quency)was not completely overcome either.In this work,to enhance the damping property of CIIR/PEAblends,PZT and CB were added to prepare CIIR/PEA/PZT/CB composites,and the effect of the PZTand CB contents on the damping property of piezo-electric composites was studied intensively.EXPERIMENTALMaterials and preparationCIIR(Exxon1068),with a Mooney viscosity andchlorination concentration of ML114(1258C)545–55and 1.1–1.3wt%,respectively,was produced byU.S.Exxon Co.(Supplied by Exxonmobil ChemicalServices Co.,Ltd.,Shanghai,China)PZT was sup-plied by Shandong Guoteng Functional Ceramic Co.,Ltd.(Dongying,Shandong,China).PEA was synthe-sized by emulsion polymerization with a K2S2O8–FeSO4redox initiator system at a temperature of25 628C.When the reaction wasfinished,PEA was obtained by the breaking of the emulsion,coacerva-tion,and drying.Phenol–formaldehyde resin(PR201),which was used as the cocuring agent of CIIR and PEA,was offered by Chongqing Resin Plant of China(Chongqing,China).Other chemicals, such as ZnO,MgO,CB,and stearic acid,were com-mercially available.PZT with alcohol was lapped in a ball mill to beshattered for48h and then was cooled and kept atroom temperature for24h.After most of the alcoholspontaneously vaporized,PZT was sieved through a net of400eyes,and this was followed by vacuum drying.PEA was blended with CIIR in a ratio of30/ 70(wt%)by a twin-roll mill for20min at1608C. After cooling,PZT,CB,PR201,and other accelerating agents were added at room temperature.The resulting blends were then vulcanized at1608C under a pres-sure of10MPa for20min.The vulcanized sheets were directly cut into certain pieces for the analysis. Electric resistance testFor the high-electric-resistance sample,the electricresistance was measured with a model ZC36megger (Shanghai Precise Scientific Instrument Co.,Shang-hai,China).For the low-electric-resistance sample, the four-electrode test method was adopted accord-ing to the American National Test Standards. Vibration analysisThe vibration performance of the composites was an-alyzed with a model3652dynamic signal analyzer (Hewlett–Packard Co.,USA)as follows:1.The vulcanized sheets were cut into6035033mm3samples,which were thenfixed at one end to an iron stand,and thefixed-frequency knock was exerted through the running of an electric engine.Through a sensor on the dynamic signal analyzer,the vibration decay time of the composites was recorded after the removal of the external force.2.The vulcanized sheets were cut into6031633mm3samples.Both ends of the samples were fixed on self-made tongs,and a cork ball with a radius of5mm was allowed to fall freely from 1m high down to the middle of the samples;then,the vibration decay time of the samples was measured by a sensor after the cork ball was removed.RESULTS AND DISCUSSIONInfluence of PZT on the damping property of the compositesThe piezoelectric composite is a new kind of damp-ing material,whose damping function mainly origi-nates from three parts:the viscoelastic damping of the polymer(a),the friction damping between the polymer andfillers orfillers themselves(b),and the piezoelectric damping of PZT(g).As for g,there are two steps of the energy dissipation process,which are shown as follows:Mechanical energyÀ!PZT Electric energyÀÀÀÀÀÀÀÀÀÀÀÀÀ!PowerÀwasting unitThermal energyTherefore,the damping property of piezoelectric composites initially depends on the conversion between the mechanical energy and electric energy. Figures1and2show the vibration attenuation of the composites with PZT contents of0and30vol%, respectively,under the condition of the cork ball bumping.From a comparison of Figures1and2,it is evident that with the10vol%content of CB unchanged,the vibration attenuation time of theCIIR/PEA/PZT/CB COMPOSITES3671Journal of Applied Polymer Science DOI10.1002/appsample with 30vol %PZT was shorter than that of the other sample without PZT.Therefore,adding the proper amount of PZT can decrease the vibration attenuation time and improve the damping property of piezoelectric composites.Figures 3and 4show the influence of the PZT content on the attenuation time of the composites knocked at a certain frequency and with a cork ball,respectively.It can be observed in both Figures 3and 4that with increasing PZT,the attenuation time of the composites shows a trend of descending ini-tially but rising subsequently and exhibits a mini-mum at a PZT content of 30vol %.The reason can be expressed as follows:as the content of PZT increases,PZT and CB will match better and better,and g and b rise,although a decreases,and D a is smaller than D b 1D g .Consequently,the integrated damping (a 1b 1g )goes up,and at the point of30vol %PZT,the piezoelectric composite attains the highest value.With the content of PZT further grow-ing,b keeps on going up;however,because the con-tent of CB is constant,the increase of g is limited,whereas a descends much at the same time.In other words,D a is much bigger than D b 1D g .As a result,a 1b 1g drops,whereas the attenuation time increases.On the other hand,too much PZT will result in excessive cost (because of its high price)and a reduction of the mechanical properties of pie-zoelectric composites because the material becomes too hard and crisp.Therefore,30vol %PZT is very condign.In addition,the PZT particles also have a certain influence on the volume resistivity of the composites,as shown in Figure 5.Under the same condition of 10vol %CB,with an increase in PZT,thevolumeFigure 1Attenuation time of the sample with 10vol %CB and withoutPZT.Figure 2Attenuation time of the sample with 10vol %CB and 30vol %PZT.Figure 3Influence of the PZT content on the damping time of composites with 10vol %CB under a knocking frequency of 50Hz.Figure 4Influence of the PZT content on the damping time of composites with 10vol %CB during knocking with a cork ball.3672LIU ET AL.Journal of Applied Polymer Science DOI 10.1002/appresistivity of the composites goes down.However,the trend of the volume resistivity,which decreases lentamente with increasing PZT,is different from that with increasing CB (as shown later in Fig.10).This is because PZT is a kind of semiconductor,and its conduction property is better than that of a rub-ber matrix but poorer than that of CB.Influence of CB on the damping property of the compositesAs mentioned previously,the second step of energy dissipation in the piezoelectric composite is the elec-tric energy/thermal energy conversion,for which CB,as a primary electric filler in the composite whose dosage is directly related to the conductivityand conversion of electric power,is one of the most important factors that affect the damping property.Figures 6and 7show the vibration attenuation of the composites with CB contents of 0and 15vol %,respectively,under the condition of the cork ball bumping.From a comparison of Figures 6and 7,it can be seen that with 40vol %PZT kept constant,the vibration attenuation time of the sample with 15vol %CB is evidently shorter than that of the sample without CB.Therefore,it is clear that adding an opportune content of CB can decrease the vibration attenuation time of the piezoelectric composite and improve its damping property.Figures 8and 9indi-cate the influence of the CB content on the attenua-tion time of the samples knocked with a certain fre-quency or a cork ball.With increasing CB,theFigure 5Change of the volume resistivity (R v )of piezo-electric composites with the PZT content varying from 0to 60vol %and with CB remaining at 10vol%.Figure 6Attenuation time of a sample with 40vol %PZT and withoutCB.Figure 7Attenuation time of a sample with 40vol %PZT and 15vol %CB.Figure 8Influence of the CB content on the attenuation time of composites with 40vol %PZT under a knocking frequency of 50Hz.CIIR/PEA/PZT/CB COMPOSITES 3673Journal of Applied Polymer Science DOI 10.1002/appattenuation time decreases first but rises afterward,and a minimum valley around 10vol %CB can be observed.When the CB and PZT particles are mixed together in the matrix,they are made of small loops;only when the volume resistivity of the composite is appropriate can every small loop become a power-wasting unit,and so it can function as the conver-sion unit from electric energy to thermal energy.Therefore,for these systems,with 10vol %CB,CB and PZT particles get in touch with each other and form conducting electric networks with appropriate electric resistance,by which the electric energy can be converted to thermal energy.To understand the effect of the CB content on the attenuation time of piezoelectric composites,the rela-tion between the CB content and electrical resistivity has been investigated,as shown in Figure 10.It is obvious that the electrical resistivity displays a declining trend with increasing CB.At the begin-ning,because the content of CB is small,its particles are scattered in the composite,and the electric net-work does not form yet;thus,the piezoelectric com-posite is in the situation of an opening circuit,and the volume resistivity is relatively high and shows a slight decrement with increasing CB loading.When the CB content goes up to 5vol %,the volume resis-tivity decreases slowly;at a certain time when CB reaches one certain critical density (10vol %or so),fillers form electric networks at the moment,and the mass resistivity goes down rapidly.When the con-tent of CB varies from 5to 15vol %,filler particles come into contact with one another,and they induce the galvanic circle ultimately.Beyond 15vol %CB,although the density of electric networks becomesbigger,a further increase in CB can raise the conduc-tivity only slightly for it exceeds the threshold.Therefore,the electric resistivity can be controlled through changes in the volume content of CB,which is a valid method to raise the power-wasting ability and the damping property.If R denotes the electric resistance of the compos-ite,C denotes the capacitance of PZT,and x denotes the vibration frequency,then R 51/x C is the best matching condition for the composite.Connecting Figures 8–10,we can see that when the content of the CB is between 5and 15vol %,the vibration attenuation time is shorter.Under this circumstance,the value of the logarithm of the volume resistivity is 2.5–9.5,so the matching mass resistivity of the composite is 102.5–109.5O cm.This scope,including the critical point of varying mass resistivity,is the most changeful district.Theoretical model for the piezoelectric composites To gain insight into the damping mechanism of pie-zoelectric composites,a theoretical model is brought forward according to the experimental results.As the scheme of Figure 11shows,when a sample is subjected to fixed-frequency knock,the combination damping property (a 1b 1g )of the material climbs up to a maximum but slides down along with CB increasing.If a composite does not contain CB,only a and a small amount of b contribute to the damping func-tion (from PZT,ZnO,etc.).PZT in the composite can transform mechanical energy into electric powerbutFigure 9Influence of the CB content on the attenuation time of composites with 40vol %PZT during knocking with a corkball.Figure 10Change of the volume resistivity (R v )of piezo-electric composites with the CB content varying from 0to 30vol %and with PZT remaining at 40vol %.3674LIU ET AL.Journal of Applied Polymer Science DOI 10.1002/appcannot implement the conversion between electric power and heat energy because it lacks the function of a conductive body;consequently,the system has no g .When the CB density is lower than 5vol %,the matrix and fillers cannot contact each other well,and this leads to its poor conductance,as shown in Figure 12(a).Under this circumstance,the piezoelec-tric composite behaves like an open circuit,so electric energy also cannot be transported into the matrix and thus cannot be converted into the thermal energy well;as a result,it can be saved only in the PZT par-ticles,which obstruct the conversion between electric energy and thermal energy.Hence,as the CB content varies from 0to 5vol %,a goes down gradually,b goes up,and g can be neglected.As a result,an increasing trend of a 1b 1g can be observed.As CB rises above 5vol %,the filler particles grad-ually get in touch with each other,leading to the for-mation of the electric networks,as shown in Figure 12(b).Like metallic networks,these electric networks run through the whole polymer matrix and become electric routes to conduct electric energy.At the same time,because of the large electric resistance of the material,the energy cannot be conducted to the surface directly but rather is converted to thermalenergy in the composite.Thus,a and b show the same tendency as the former stage,but g is greatly enhanced.With a further increase in CB,filler particles come into intimate contact with one another,and the elec-tric network becomes more and more compact,as shown in Figure 12(c);this makes the electric resist-ance of the composite become smaller and smaller.Therefore,a short circuit in the piezoelectric compos-ite gradually is formed (>15vol %CB),which can conduct electric energy to the composite surface quickly,it being equal to connect the ground,at which the electric energy cannot be converted into the thermal energy;as a result,g decreases greatly.At the same time,a goes down and b goes up.As a result,a 1b 1g is depressed from the maximum.In a word,by the variation of the CB content,the composite can transform from an open circuit to a loop circuit to a short circuit;and within the scope of the loop circuit,the piezoelectric composite can carry out the conversion of mechanical energy to electric energy to thermal energy.CONCLUSIONSIn this work (for purpose of damping applications),CIIR/PEA/PZT/CB composites were prepared.The results from research on the properties of the com-posites show that the damping behavior of the com-posites strongly depends on the contents of CB and PZT,and when the contents of CB and PZT are between 10and 30vol %,the volume resistivity of the materials is between 105and 109.5O cm,and a good damping performance can be achieved.There-fore,by the adjustment of the electrical resistance to a suitable range by the variation of the CB content,the composites can behave as semiconductors,in which the electric energy is not transferred to the surface of the material but rather is dissipated as thermal energy.According to the results,a theoreti-cal model based on an open circuit to a loop circuit to a short circuit has been proposed to explain the damping performance of the composites.References1.Min,B.G.;Stachurski,Z.H.;Hodgkin,J.H.;Heath,G.R.Polymer 1993,34,3620.2.Fay,J.J.;Murphy,C.J.;Thomas,D.A.;Sperling,L.H.Polym Eng Sci 1991,31,1731.3.Foster,J.N.;Sperling,L.H.J Appl Polym Sci 1987,33,2637.4.Hourston,D.J.;Aughes,I.D.J Appl Polym Sci 1977,21,3487.5.Chang,M.C.O.;Thomas,D.A.;Sperling,L.H.J Polym Sci Part B:Polym Phys 1988,26,1627.6.Uchino,K.;Ishii,T.Jpn Ceram Soc Scholarly Pap Mag 1988,96,863.7.Sumita,M.;Gohda,H.;Asia,S.;Miyasaka,K.;Fukuda,A.;Suzuki,Y.;Utino,K.Macromol Rapid Commun 1991,12,657.Figure 12Schematic representations of the circuit models:(a)open circuit,(b)loop circuit,and (c)shortcircuit.Figure 11Schematic representation of the effect of CB on the volume resistivity and damping performance of the composites.CIIR/PEA/PZT/CB COMPOSITES 3675Journal of Applied Polymer Science DOI 10.1002/app8.Sumita,M.Shinsozai1993,4,66.9.Asai,S.;Nakashima,M.;Sumita,M.;Kaneko,H.;Kaneko,I.;Ohhira,Y.;Hori,M.J Mater Sci Jpn1997,34,244.10.Sumita,M.Koubunshi1997,46,116.11.Sumita,M.Funct Mater1995,15,12.12.Akasaka,S.;Sumita,M.;Date,M.;Tokushima,T.Meet PolymMater Forum Text Soc Polym Sci Jpn1997,6,165.13.Wu,C.Y.;Qian,S.Y.;Wu,C.F.J Funct Polym2005,4,586.14.Zhou,X.Q.;Wu,C.F.Chin J Nonferrous Met2004,2,232.15.Newnham,R.E.;Schembeim,J.I.;Lee,J.W.J Intell MaterSyst Struct1993,7,289.16.Hagood,N.W.;Flotow,A.von.J Sound Vibr1991,146,243.17.Sumita,M.;Gohda,H.;Asai,S.;Miyasaka,K.;Furuta, A.;Suzuki,Y.;Uchino,K.Macromol Rapid Commun1991,12, 657.18.Hori,M.;Aoki,T.;Ohira,Y.;Yano,pos A2001,32,287.19.He,X.R.;Huang,G.S.;Wang,J.H.China Synth Rubber Ind2005,28,44.3676LIU ET AL. 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四川省广安市2023-2024学年高一下学期7月期末英语试题一、阅读理解Here’re some new reads that you might enjoy.Daughters of the LampSahara has always felt insignificant. She always has a plan. But a necklace (项链) belonging to her late mother changes all of that. Sahara goes to a family wedding in Cairo, Egypt. There, as she looks into the origin of the necklace, family secrets are unearthed. Author Nedda Lewers put Arabian fairy stories into this magic al adventure. The book surely interests teens.The Partition ProjectMaha loves storytelling. She explorers her grandmother’s life story by making a documentary about her. Maha learns about her grandmother’s experience growing up in India and her move from India to Pakistan. The book, by Saadia Faruqi, focuses on the importance of family relationship. It is for children aged 13 and above.Shiny MisfitsWritten by Maysoon Zayid, and illustrated by Shadia Amin, this novel grabs you from the first chapter. Bay Ann has a brain disease, but she doesn’t let that hold her back. She loves tap dancing, and decides to perform at her school talent show. She hopes doing so will get her closer to her dream. It always encourages teens to study hard.Zombie TrainImagine a world where people turn into zombies (僵尸) because of a kind of insect that affects only grown-ups. In this book by David Macinnis Gill, which is for the taste of teenagers, a boy named Wyatt is on a train filled with kids he’s protecting. He meets Ryle who gains his trust. But Ryle has a plan to hijack (抢劫) the train so she can get to Nirvana, where there’s a cure. 1．Which is about a patient’s struggle story?A．Daughters of the Lamp.B．The Partition Project.C．Zombie Train.D．Shiny Misfits.2．What can we say about David Macinnis Gill?A．He’s an author.B．He’s a character in a book.C．He’s a train driver.D．He’s a book illustrator.3．What do the books listed above have in common?A．They’re about family relationships.B．They’re written by the young.C．They’re suitable for teenagers.D．They’re based on true stories.I would treasure every moment on the hockey arena (冰球场). My dream job would be to become a professional hockey player. I grew up playing hockey in local leagues. I was never the star player on the team, but hockey was always something I eagerly expected every day, simply enjoying the game.It has been seven years since I last played hockey, and I deeply miss the excitement of driving to the arena with my family, scoring a goal, making an important save (扑救), or simply being part of a team.Being a professional hockey player makes big money. For example, Connor McDavid signed a $100 million deal with the Edmonton Oilers in 2017. But, in fact, very few people like the career only because of this. The majority of people play it because they love the game. For me, it’s not about the money or the fame (名声). If I were in their skates, I’d treasure every second on the ice.I’d treasure every step on the ice of famous hockey arenas like Madison Square Garden, Bell Centre, Rogers Arena, and Scotiabank Arena. I’d enjoy every moment sharing the ice with future Hall-of-Famers like Sidney Crosby, Alexander Ovechkin, Patrick Kane, and Carey Price.I’d feel like the luckiest person alive every time I’m reminded that I’m living the dream—a dream many, like me, would give anything to experience. Twenty-three lucky individuals for each team have the honor to tell the world with pride that they play hockey professionally and support their families. I’d devote myself to anything for the chance to be among them. Yes, professional hockey players earn significant salaries, but if given the opportunity, I wouldn’t ask for a single dollar.4．What can we say about the author concerning hockey?A．He showed no interest in hockey.B．He started a local hockey team.C．He was not good at playing hockey.D．He played hockey due to his family. 5．What inspires many people to be hockey players?A．The money they make.B．Their love for competition.C．The desire for fame.D．Their interest in the game.6．Why does the author mention the famous hockey arenas?A．To highlight his dream.B．To show hockey is popular.C．To explain his rich experiences.D．To recommend them to hockey lovers. 7．What does the author want to tell us in the last paragraph?A．Gaining success helps become an expert.B．We should stay true to what we run after.C．Nothing is impossible for a willing heart.D．All things are difficult before they are easy.According to the United Nations, there’s plastic litter at the bottom of the ocean and on top of Mount Everest. Now plastic has been found in another unlikely place: on the backs of hermit crabs (寄居蟹).According to a study released in February, 2024, hermit crabs are using plastic litter as shells (外壳). Zuzanna Jagiello, a biologist at the University of Warsaw, in Poland, is the study’s lead author. She said, “They don’t have homes, so they use rubbish.” Jagiello studies the Anthropocene age. That’s the age we’re in now. Scientists consider it as the period in which human activity has had a major impact on the environment. Hermit crabs’ using plastic waste as shells is one example of that impact.Hermit crabs are small, soft-bodied crabs that live near oceans. To protect themselves from enemies, in general, they wear seashells that have been left behind by dead sea snails (海螺). But according to February’s study, at least 386 hermit crabs have been documented wearing rubbish. Of the world’s 16 species of hermit crabs that live on land, 10 have been seen wearing rubbish. Nearly nine out of every 10 of those crabs were wearing plastic waste, such as bottle caps.Scientists aren’t sure why hermit crabs are choosing litter instead of snail shells. But they have theories. Some sea snail populations are declining. Hermit crabs could be turning to litter because they can’t find enough seashells. It’s also possible that crabs are opting for plastic because it’s light and easy to carry. Or they’re drawn to its flamboyant materials. Scientists agree that plastic pollution harms wildlife and their living places in many ways. But it isn’t clear that the crabs are in any danger. “It’s really an amazing example of the beauty of adaptation,” Jagiello says. “What are the long-term results of these adaptations? We don’t know.”8．What do scientists think of hermit crabs’ using plastic waste as shells?A．They’re products of the environment.B．They don’t have to use their homes.C．They don’t have enough food to eat.D．They have ability to live alone.9．What do we know about hermit crabs?A．Their population is becoming smaller.B．Their physical health is getting worse.C．They typically wear seashells not litter.D．They are moving out of the oceans. 10．What does the underlined word “flamboyant” in the last paragraph mean?A．Real.B．Colorful.C．Familiar.D．Expensive. 11．What’s the best title for the text?A．Less Plastic, More Creative Crabs B．The Anthropocene Age’s CrabsC．More Hermit Crabs, Less Polluted D．Hermit Crabs in Plastic ShellsA person’s IQ is a measurement of a person’s intelligence. It stands for intelligence quotient, the amount or degree of intelligence. IQ tests have been around since the beginning of the 20th century, although people have been trying to measure intelligence for much longer than that.French psychologist Alfred Binet was one of the first people to come up with what we know as the IQ test. In 1905, he was tasked with creating a tool for measuring which students in school were more likely to do poorly. A new law had been passed in France that made all children go to school. Education leaders wanted to know the children who were not as intelligent as the others.Binet developed a test that would consider two factors: a child’s chronological age (How old was he or she?) and a child’s mental age (Was the child thinking at, below, or above the level of other children his or her age?). He developed questions for specific age groups. If a child could answer questions that older children could answer, that child’s mental age was higher than his chronological age. If a different child could not answer questions that children his own age could answer, then that child’s mental age was lower than his chronological age.Binet did not believe his test fully measured a person’s intelligence. He felt intelligence was something you could not put a number on. He said more research needed to be done. Despite this, an American psychologist at Stanford University read Binet’s work and confidently developed the test further. It became known as the Stanford-Binet Intelligence Scales. This test became one of the most popular IQ tests of the 20th century. The test may be useful, but some people said that Alfred Binet was right: intelligence is more than just a number.12．Why did Alfred Binet create the IQ test?A．To keep poor students out of school.B．To separate weak students from others.C．To measure students’ daily behaviour.D．To make laws for poor but clever students. 13．Which aspect of Binet’s IQ test is paragraph 3 mainly about?A．Its results.B．Its subjects.C．Its methods.D．Its origins. 14．What was the attitude of the American psychologist mentioned to his own IQ test?A．Doubtful.B．Favorable.C．Unclear.D．Negative. 15．What’s the main purpose of the text?A．To provide some explorations of intelligence.B．To present a new intelligencemeasurement.C．To compare the measurements of intelligence.D．To list the benefits of applyingintelligence fully.Let’s talk now about how to visit a museum right once you are inside of it.Dress properly. This is quite important for visiting museums. For example, when in the museum you won’t walk that much, but you’ll stand on the same spot a lot. 16 Wearing some comfortable shoes is necessary for a great museum experience.Don’t spend more than two hours at a museum. From my experience, after two hours at the museum, you’ll be too tired to continue exploring it. Just walking around in the museum without any idea of what you’re looking at won’t be the best experience. 17 That way, you can really enjoy the artwork, learn the story behind it and have a great museum experience.18 One of my favourite things about visiting museum s is to talk about the art pieces. If you’ll visit the museum on tour, feel free to ask your guide who often knows the artworks well all the questions you have. Why is that painting so famous? How long would an artist need to create a marble statue (大理石雕像)? 19Avoid taking pictures. Although some exhibits could be so beautiful and interesting to you, don’t take photos of them. 20 You’re damaging the paintings that are often hundreds of years old if using the flash. And since the light is not bright at museums, the quality of your photos won’t be the best. Another thing is that you are damaging other visitors’ experience.A．And that could be tiring.B．There are good reasons for this.C．Ask everything that interests you.D．Pick only one collection and explore it deeply.E．Anyway, use the advantage of having an expert with you.F．Find great high-quality photos of the paintings on their website.G．The step of researching the museum collections before your visit is important.二、完形填空Naomi Harper,23, runs a café in London where lonely and unhappy people can come and talk. It opened a few months ago and has now got 21 . So many people come here.She first got the 22 when a homeless man turned to her for help in the street one night. There was no place to 23 him, talk properly and give comfort. She always feels moved by the people who open 24 or make donations.The café was 25 a disused shop, owned by a local church. Naomi rented it and has hired a group of people to 26 . It is called the Open Door.When Naomi was at college, she used to work with her father in the afternoons. Her father is always 27 to help others. He is an eye doctor who sets up camps and performs operations in poor areas of the world. Naomi was 28 by her father and hopes to 29 helping those in need. “I 30 a sense of achievement from the work I do, though tired. My greatest 31 is when I see somebody happy,” she said.In November, Naomi made worldwide headlines when she 32 the café with her father’s help while running a charity event to 33 money for a local children’s hospital. Naomi devotes all her energy to 34 and doesn’t have much time for other activities.35 , she obtains much pleasure from her work.21．A．simple B．famous C．different D．familiar 22．A．idea B．task C．money D．experience 23．A．visit B．follow C．house D．guide 24．A．stores B．doors C．shelters D．companies 25．A．temporarily B．naturally C．eventually D．originally 26．A．show off B．help out C．hold back D．move on27．A．thankful B．ready C．afraid D．nervous 28．A．influenced B．protected C．observed D．trusted 29．A．finish B．advise C．appreciate D．continue 30．A．exchange B．remember C．gain D．copy 31．A．choice B．joy C．role D．opinion 32．A．reached B．saw C．opened D．left33．A．raise B．spend C．save D．borrow 34．A．study B．life C．health D．charity 35．A．However B．Besides C．Otherwise D．Therefore三、语法填空阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。

阅读/写作Writing/ReadingIf you can't annoy somebody， there's little point in writing.-- Kingsley AmisThe covers of this book are too far apart.-- Ambrose BierceNOVEL， n. A short story padded.-- Ambrose Bierce， The Devil's Dictionary， 1911STORY， n. A narrative， commonly untrue.-- Ambrose Bierce， The Devil's Dictionary， 1911Beneath the rule of men entirely great， / The pen is mightier than the sword.-- Edward Robert Bulwer-Lytton， Richelieu， II. iiA good novel tells us the truth about its hero； but a bad novel tells us the truth about its author.-- G. K. ChestertonTruth must necessarily be stranger than fiction， for fiction is the creation of the human mind and therefore congenial to it.-- G. K. ChestertonThe difference between fiction and reality？ Fiction has to make sense.-- Tom ClancyMore than kisses， letters mingle souls.-- John DonneSome editors are failed writers， but so are most writers.-- T. S. EliotI am returning this otherwise good typing paper to you because someone has printed gibberish all over it and put your name at the top.-- English Professor， Ohio UniversityI have read your book and much like it.-- Moses Hadas， book reviewerThank you for sending me a copy of your book - I'll waste no time reading it.-- Moses Hadas， book reviewerThis book fills a much-needed gap.-- Moses Hadas， book reviewerManuscript： something submitted in haste and returned at leisure.-- Oliver HerfordWhy don't you write books people can read？-- Nora Joyce， to her husband JamesIf I were to try to read， much less answer， all the attacks made on me，this shop might as well be closed for any other business.-- Abraham LincolnFrom the moment I picked your book up until I laid it down I was convulsed with laughter. Some day I intend reading it.-- Groucho MarxIn literature as in love， we are astonished at what is chosen by others.-- André MauroisAfter all， all he did was string together a lot of old， well-known quotations.-- H. L. Mencken， on ShakespeareAuthor： A fool， who， not content with having bored those who have lived with him， insists on tormenting the generations to come.-- MontesquieuEverywhere I go， I'm asked if the universities stifle writers. My opinion is that they don't stifle enough of them.-- Flannery O'ConnorThere's many a bestseller that could have been prevented by a good teacher.-- Flannery O'ConnorThis novel is not to be tossed lightly aside， but hurled with great force.-- Dorothy ParkerTo write a good love letter， you ought to begin without knowing what you mean to say， and to finish without knowing what you have written.-- Jean Jacques RousseauAnyone nit-picking enough to write a letter of correction to an editor doubtless deserves the error that provoked it.-- Alvin TofflerI didn't have time to write a short letter， so I wrote a long one instead.-- Mark TwainSubstitute "damn" every time you're inclined to write "very"； your editor will delete it and the writing will be just as it should be.-- Mark TwainThe man who does not read good books has no advantage over the man who cannot read them.-- Mark TwainA poem is never finished， only abandoned.-- Paul ValeryParenthetical remarks （however relevant） are unnecessary.-- Frank L. Visco， How to Write GoodI don't know which is more discouraging， literature or chickens.-- E. B. WhiteBiography lends to death a new terror.-- Oscar WildeThere is no such thing as a moral or an immoral book. Books are well written or badly written.-- Oscar WildeI am a bear of very little brain， and long words bother me.-- Winnie the Pooh， character created by author A. A. MilneLiterature is strewn with the wreckage of those who have minded beyond reason the opinion of others.-- Virginia WoolfAlthough written many years ago， Lady Chatterley's Lover has just been reissued by the Grove Press， and this pictorial account of the day-to-day life of an English gamekeeper is full of considerable interest to outdoor minded readers，as it contains many passages on pheasant-raising， the apprehending of poachers，ways to control vermin， and other chores and duties of the professional gamekeeper. Unfortunately， one is obliged to wade through many pages of extraneous material in order to discover and savour those sidelights on the management of a midland shooting estate， and in this reviewer's opinion the book cannot take the place of J. R. Miller's Practical Gamekeeping.-- Ed Zern， Field and Stream， November 1959。