J.Graphene sheets are also prone to defects and“very difficult to make in good quality,”Ron Mertens，owner and editor of Graphene-Info.tom，said.Production capacity is also very limited.“There are thousands of small companies that can make graphene，but it’s expensive and low-capacity,”Mertens said.alround wafer measuring one inch in diameter,for instance，costs about$1 00，he added.

K.An even thornier obstacle on the way to graphene transistors is the fact that the material has no“band gap，”an essential property that allows transistors to be turned on and off without leaking electronic charge in the“off”state，said Elias Towe，a professor of electrical and computer engineering at Carnegie Mellon University.

L.“Band-gap engineering has been and remains the biggest challenge in the development of graphene transistors and computer chips.”Lau said.It requires controlling the material almost down at the atomic level，and“that’s really pushing the edges of existing technology,”Patterson said.“In 10 years，we’11 start to see these problems solved.”

‘It is largely a matter of time’

M.If graphene is to succeed as a replacement for silicon，every unit of cost and performance will make a difference，Towe said.

N.“Silicon is hard to displace，with all the billions dollars of investments made in manufacturing infrastructure，”he said.“A replacement for silicon has to offer extraordinary performance at extremely rock-bottom cost to compel industry to change its way.”

O.Though graphene is just 10 years old—in contrast,use of silicon in transistors dates to the early 1950s—considerable progress has already been made.For example，the largest graphene sheet was produced by hand in a laboratory eight years ago;its width was less than that of a human hair.“Nowadays，roll-to-roll printing of graphene sheets up to 1 00 meters long has been achieved，”Lau said.“With the increasing interest，investment，and research in graphene-based technology,I think it is largely a matter of time before the economy of scale kicks in and truly low-cost，large-scale production ofhigh-quality graphene is accomplished，”she added.

注意：此部分试题请在答题卡2上作答。

Nanoplatelet is the powder-or flake-type of graphene that has been used for some time to make conductors and that is being launched on the market.

48、 To encourage industry to replace silicon with graphene，it is necessary for graphene to provide high property at an extremely low expense.

49、 While graphene flakes are roughly processed with bulk graphite，graphene sheets are carefully made on substrates like copper，germanium，or silicon carbide.

50、 In the past ten years.graphene has become a hot topic among the scientific and technology groups.

51、 Perforene won’t come into the market before it can be manufactured at a very low cost.

52、 Despite of a much younger age than silicon，great progress has been made in graphene;and with ever increasing interest，investment and research in graphene technology,it’s probable to manufacture cost- effective graphene of high quality.

53、 Graphene has been attempted to be used for plenty of noticeable applications.

54、 Yet it still needs to take ten years for graphene to be used in semiconductors，which lies at the heart of the technology.

55、 With today’s technology,it is still impossible to control material down at the atomic level.

56、 Elias Towe pointed out that having no“band gap”，the dispensable feature of transistors，makes it more difficult to produce graphene transistors.

Section C Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A), B), C) and D). You should decide on the best choice and mark the corresponding letter on Answer Sheet 2 with a single line through the centre.

57、根据以下资料，回答57-66题：

Passage One

Quesaons 56 to 60 are based on thefollowingpassage.

The vast glaciers of western Antarctica are rapidly melting and losing ice to the sea and almost certainly have“passed the point of no return，”according to new work by two separate teams of scientists.

The likely result：a rise in global sea levels of 4 feet or more in the coming centuries，says research made public Monday by scientists at the University of Washington，the University of California-Irvine and NASA's Jet Propulsion Laboratory.

“It really is an amazingly distressing situation，”says Pennsylvania State University glaciologist(冰川学家)Sridhar Anandakrishnan，who was not affiliated with either study.“This is a huge part of West Antarctica.and it seems to have been kicked over the edge.”

The researchers say the fate of the glaciers is almost certainly beyond hope.

One study shows that a river of ice called Thwaites Glacier is probably in the early stages of collapse.Total collapse is almost inevitable.the study shows.

A second study shows that a halfdozen glaciers are pouring ice into the sea at an ever-greater pace.That will trigger 4 feet of sea-level rise，says study author Eric Rignot，a glaciologist at the University of Califomia-Irvine，and NASA's Jet Propulsion Laboratory.

“The retreat of ice in that area is unstoppable，”Rignot said at a briefing Monday,adding that the glaciers have“passed the point of no return.”

Rignot and his team used data from satellites and aircraft to map changes in six West Antarctic glaciers and the terrain underlying these massive ice floes(浮冰).The data show the glaciers are stretching out，thinning and shrinking in volume.They’re A.so flowing faster from the continent’s interior to the sea，dumping larger quantities of ice into the ocean than before and thereby raising sea levels.

At the same time，the portion of each glacier projecting into the sea is being melted from below by warm ocean water.That leads to a vicious cycle of more thinning and faster flow,and the local Terrain offers no barrier to the glaciers’retreat，the researchers report in an upcoming issue of Geophysical Research Leaers.

A report in this week’s Science says the Thwaites Glacier will collapse.perhaps in 200 years.The paper doesn’t specify the amount of sea-level rise associated with nlwaites’demise.

Who contributed to the Monday research?

A.The two separate teams of scientists.

B.Scientists at the University of Washington，of California.Irvine and NASA's Lab.

C.Scientists at Pennsylvania State University.

D.Several glaciologists.

58、 What is the current situation of Thwaites Glacier?

A.It is on the edge of inevitable collapsing.

B.It has completely gone.

C.It is becoming 1arger in volume.

D.It is flowing to the sea.

59、 What are the problems ofAntarcfic glaciers?

A.They are becoming smaller in volume.

B.They are flowing at a faster speed to the sea.

C.They ale pouring more and mole ice into the sea.

D.All the above.

60、 What does the report in Geophysical Research Letters show?

A.The ice poured into the sea is being melted from above.

B.The melting of the ice can result in the vicious cycle of the glaciers’melting.

C.The local terrain has nothing to do with glacier retreat.

D.Warm ocean water can slow down the glaciers’melting.

61、 According to the passage，what do the words“passed the point of no return”mean(Line 2，Para.1)?

A.The glaciers can’t flow back to the continents.

B.The glaciers are different from what they were years ago.

C.The melting of glaciers has come to the stage of being inevitable.

D.The speed of glacier melting can’t return to the former one.

62、 根据以下资料，回答62-71题：

Quesaons 61 to 65 are based on thefollowingpassage.

In 2005，the medical examiner in Wichita，Kansas，noticed a cluster of deaths that were unusually similar in nature：in three years，sixteen men and women，between the ages of twenty-two and fifty-two，had died in their sleep.In the hours before they lost consciousness，they had been sluggish and dopey,struggling to stay awake.A few had complained of chest pain.“I can’t catch my breath，”one kept saying.

All of them had taken painkillers prescribed by a family practice called the Schneider Medical Clinic.

The clinic was in Haysville.a working.class suburb of Wichita.The main industries in the area were aircraft and plastics，neither of which was doing well.A mile sout of the clinic，there was little except wheat fields.The chief doctor was Stephen Schneider,a fifty-one-year-old osteopath(整骨师)with sandy hair and dimples.He treated the county commissioner and the chief of police，gave physicals to the boys at the Haysville high school，and did rounds at local nursing homes.One of his patients，Jeffrey Peters，told me that Schneider reminded him of the“kind of family doctor we had forty years ago.when l was growing up—a doctor who will sit down and listen to you and ioke around and make you feel comfortable.”

On September 13，2005，Schneider arrived at work to find the clinic cordoned(包围隔离)off with police tape.He called his wife，Linda Atterbury,a blond，peppy forty-seven-year-old nurse，who was at home with their two young daughters，and told her to come to work.Agents from the Kansas Bureau of Investigation and the Drug Enforcement Administration led Schneider into one of the clinic’s fourteen exam rooms and asked him why he had been prescribing so many opioid(鸦片类)painkillers.He responded that sixty per cent of his patients suffered from chronic pain，and few other physicians in the area would treat them.The agents wrote.“He tries to believe his patients whenthey describe their health problems and he will believe them until they prove themselves wrong.”When asked how many of his patients had died,Schneider said that he didn’t know…

注意：此部分试题请在答题卡2上作答。

What’s the similar nature of the 16 people’s death?

A.They were examined by the same medical examiner.

B.They were treated by the same docton

C.Thev all died in their sleep.

D.Their ages are roughly the same.

63、 What were the common symptoms they had before they died?

A.They were sluggish and dopey before losing their consciousness.

B.They had taken painkillers from the same docton

C.They got hurt in their chest.

D.They couldn’t breathe.

64、 Where did Schneider Medical Clinic locate?

A.In the center of Wichita.

B.A mile north of a large wheat field.

C.A place which did well in aircraft and plastics.

D.A rich upper-class area in Haysville.

65、 What was the family doctor like 40 years ago?

A.Serious and strict.

B.Cold.hearted.

C.Cruel and vicious.

D.Sincere and considerate.

66、 Why was Schneider’s clinic visited by the police?

A.Because the doctor was selling opioid painkillers to the patients.

B.Because the clinic was the only one in this area.

C.Because the doctor abused his patients.

D.Because the police wanted to use the clinic as an exam place.

Part III Reading Comprehension.(40 minutes)

Part IV Translation.(30minutes) Directions: For this part, you are allowed 30 minutes to translate a passage from Chinese into English. You should write your answer on Answer Sheet 2.

67、故宫(Imperial Palace)位于北京城的中心，是明清两代(Ming and Qing Dynasties)的皇宫，是中国现存最大的古代木构建筑群。故宫始建于l406年，历时十四年后竣工，迄今已有5000多年的历史。气势雄伟的故宫是中国古建筑艺术的精华，里面保存有大量稀世文物和珍宝，对于研究明清两代及历代艺术具有重要意义。1987年被联合国教科文组织(UNESCO)列入“世界人类文化遗产”。

注意：此部分试题请在答题卡2上作答。

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