1 . Directions: Fill in each blank with a proper word chosen from the box. Each word can be used only once. Note that there is one word more than you need.

A. date B. current C. timely D. approach E. properties F. literally G. applications H. alternative I. implementation        J. leaks K. potentially

Researchers have used liquid metals to turn carbon dioxide back into solid coal, in a world-first breakthrough that could transform our     1     to carbon capture and storage.

The research team led by RMIT University in Melbourne, Australia, have developed a new technique that can efficiently convert CO2 from a gas into solid particles of carbon.

Published in the journal Nature Communications, the research offers a(n)     2     pathway for safely and permanently removing the greenhouse gas from our atmosphere.

Current technologies for carbon capture and storage focus on compressing CO2 into a liquid form, transporting it to a suitable site and injecting it underground.

But     3     has been hindered (阻碍) by engineering challenges, issues around economic feasibility and environmental concerns about possible     4     from the storage sites.

RMIT researcher Dr Torben Daeneke said converting CO2 into a solid could be a more sustainable approach. “While we can’t     5     turn back time, turning carbon dioxide back into coal and burying it back in the ground is a bit like rewinding the emissions clock,” Daeneke, an Australian Research Council DECRA Fellow, said.

“To     6    , CO2 has only been converted into a solid at extremely high temperatures, making it industrially unfeasible.” By using liquid metals as a catalyst, we’ve shown it’s possible to turn the gas back into carbon at room temperature, in a process that’s efficient and scalable. While more research needs to be done, it's a crucial first step to delivering solid storage of carbon.”

How the carbon conversion works

Lead author, Dr Dorna Esrafilzadeh, a Vice-Chancellor’s Research Fellow in RMIT’s School of Engineering, developed the electrochemical technique to capture and convert atmospheric CO2 to storable solid carbon.

To convert CO2, the researchers designed a liquid metal catalyst with specific surface     7     that made it extremely efficient at conducting electricity while chemically activating the surface. The carbon dioxide is dissolved (溶解) in a beaker (无柄塑料杯) filled with an electrolyte liquid and a small amount of the liquid metal, which is then charged with an electrical     8    .

The CO2 slowly converts into solid flakes of carbon, which are naturally detached (脱离) from the liquid metal surface, allowing the continuous production of carbonaceous solid. Esrafilzadeh said the carbon produced could also be used as an electrode.

“A side benefit of the process is that the carbon can hold electrical charge, becoming a supercapacitor (电容器), so it could    9     be used as a component in future vehicles. The process also produces synthetic fuel as a by-product, which could also have industrial     10    .”

2 . Directions：After reading the passage and the sentences below,fill in each blank with a proper word given in the box. Each word can be used only once. Note that there is one more word than you need.

A. suggest     B. disorders          C. permanent        D. age-related        E. periods        F. average     G. experience        H. differently        I. appearing     J. uncommon       K. luxury

Napping May Improve Learning

Getting a good night's sleep is important for the learning and memory process. It's important because it stores the training exercises and the learning exercises into our more     1    memory while we're sleeping 7-8 hours in bed. And then the next morning when you wake up your mind is better prepared to act on that information.

But what about getting rest during the middle of the day？Short     2     of sleep may help our brains work better,or so says a recent study on napping. Taking a nap may also help this group of people fight off     3     memory loss. Many Americans do nap. But one-third of all adults in the United States are also chronically tired,notes the U.S. Centers for Disease Control and Prevention (CDC). It found that 50 million to 70 million Americans have chronic sleep     4    . So,someone who naps as a way of paying off a sleep debt may not     5     the same improvements from napping as a healthy,well-rested person would. Also,many people may not want to admit that they take naps. They may think that napping shows they are weak or lack energy. That only children,the very old,sick or lazy people nap is not a(n)     6     opinion.

In fact,Americans sometimes do a very strange thing. Some brag about how few hours of sleep they need each night. Health experts     7    that adults get seven to eight hours of sleep each night. People who claim they only sleep four or five hours a night,they may think they are superhuman,somehow stronger than the     8    human. However,that may be changing. Many offices now offer napping rooms and napping cafes are     9    in many U.S. cities,including Washington,D.C. While resting in the middle of the work day may seem like a(n)     10    to Americans,napping is very much part of a normal,everyday life in other parts of the world.