While jewelry made from gold can be beautiful, most people admit that wearing the heavy metal over long periods of time can get a little annoying. Now, researchers from Swiss university ETH Zurich have created a new form of lightweight gold that weighs five to ten times less than traditional 18-carat gold—which typically consists of 75 percent gold and 25 percent copper—but has the same purity.
The researchers began by mixing gold with water, salt, protein fibers and other materials. They then replaced the water with alcohol and placed the mixture inside a high-pressure carbon dioxide (CO2) box. The reaction between the gas and alcohol transformed the golden plastic into a light material that can be heated to melt and made into whatever form was needed. "This gold has some characteristics of plastic,” says team leader Raffaele Mezzenga, professor of Food and Soft Materials at ETH Zurich.
In addition to being lighter, the "plastic” gold has other advantages over traditional forms. It can be melted into shape at about 105 degrees Celsius, much lower than the 1,064 degrees Celsius required to melt pure 24-carat gold. The metal's firmness can be easily adjusted by changing the components at the beginning of the process. It is also much easier to vary the color. "As a general rule, our approach lets us create almost any kind of gold we choose, in line with the desired properties, says Mezzenga.
The researchers, who published their study in the journal Advanced Functional Materials on January 10, 2020, believe the new lightweight gold will be able to replace the metallic version in most traditional applications, including jewelry and watches. However, given that most buyers associate high-quality gold with weight, that may take some time. But the material will undoubtedly be beneficial for use inside electronic devices, chemical catalysts (催化剂),and even radiation shielding.
1.Why do many people find the traditional gold annoying?
A.It costs too much。
B.Its purity is too low.
C.It feels too heavy to wear long.
D.Its beauty lasts a short time,
2.What is the second paragraph mainly about?
A.The functions of the "plastic" gold.
B.The components of the "plastic” gold.
C.The characteristics of the "plastic” gold.
D.The production process of the "plastic" gold.
3.Which is the "plastic" gold's advantage over the traditional gold?
A.It is easier to process.
B.It is more widely used.
C.It has a lower temperature.
D.It is more convenient to get.
4.Where is this text most likely from?
A.A diary. B.A guidebook.
C.A novel. D.A magazine.
An elephant, who accidentally fell into a dry, 25-foot deep well in Northeast India, lived to see another day thanks to the quick-thinking rescuers' scientific knowledge. The chain of events unfolded early in the morning on Tuesday, January 28, 2020, when citizens of Amliya toli village, in the state of Jharkhand, awoke to the cries of the trapped animal and called the forest department for help.
When the rescuers arrived, they instantly realized that pulling out the huge animal, which seemed to be about 30 years old, was not a practical idea. Fortunately , the forest department officials had been paying attention in their science class and were well aware of the Archimedes' principle. The physics law of buoyancy(浮力)，which explains how ships stay afloat, states that when a body is partially or fully immersed in a liquid, it experiences an apparent loss in weight that is equal to the weight of the liquid displaced by the part of the body in the liquid.
In this case, that meant filling the well with enough water to displace the elephant's weight. It took the three motorized pumps over three hours to add the hundreds of gallons needed to enable the heavy animal to float up to the surface. However, it was well worth the effort. A heart-warming video shows the villagers cheering as the animal, using the makeshift ramp (斜坡)dug by the rescue team, pulls itself out of the well and walks away to safety in the nearby forest.
1.Who first found the trapped elephant?
A.Some scientists. B.Forest rescuers.
C.Nearby villagers. D.The forest department officials.
2.How did the rescuers feel about pulling out the elephant?
A.Impossible. B.Challenging. C.Secure. D.Realistic.
3.What does the underlined word “immersed” in Paragraph 2 probably mean?
A.Broken. B.Covered. C.Stuck. D.Dampened.
4.What can be the best title for the text?
A.An Elephant Trapped in the Water
B.Villagers Used Water to Save Animals
C.Forest Rescuers Invented a New Technique
D.An Elephant Saved by the Archimedes' Principle
Websites
ESPN Sports Programming
ESPN takes its sports content and programming to the next level with its dynamic and eye-catching site filled with large, high-quality pictures and videos. The "featured sports" slider is thoroughly entrancing and does an excellent job of showcasing each of the sports alongside interesting statistics and informative details about available programs.
Revols
Revols takes a bold （突出的）approach on its website by enlarging its small, advanced headphones in photographs and videos. The photography and video make the site amazingly product-focused, so its users slowly become more and more absorbed in the experience these headphones can give you. The large font （字型）treatment on this site is also a nice touch and adds to the larger-than-life earbud photography.
Zillow
Finding the perfect home is all about being able to conveniently research exactly what you're looking for, save and store what you like, and make it easy to find it all later on. Zillow hits the nail on the head for all three of these points. The search area within the hero area makes it easy for new users to quickly select and search listings without having to look for some hidden search page.
Montage
Montage takes showing-off its product to the next level with this homepage that clearly outlines what its product is, how it looks, product quality, and testimonials. The site is an excellent example of one approach you can use to highlight your product and the most important points your users would be concerned with finding answers to.
1.Which website stresses the product by making it seem big?
A.ESPN Sports Programming, B.Revols.
C.Zillow. D.Montage.
2.What can users do on Zillow?
A.Order a product.
B.Buy a headphone.
C.Learn about sports.
D.Find a suitable house.
3.What do the four websites have in common?
A.They are well designed.
B.They make shopping easier.
C.They are intended for new users.
D.They help users learn new knowledge.
假定你是李华。你之前在网上为你校交换生Jack预定了下周六晚上7：30的川剧演出， 现该演出被宣布取消，请给他写一封邮件，内容要点如下：
1. 告知演出取消；
2. 后续事项处理；
3. 其它活动建议。
注意：1. 词数100左右；
2. 可适当增加细节，以使行文连贯。
Dear Jack,
________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Yours,
Li Hua
假定英语老师要求同桌之间互相修改作文，请你修改你同桌写的以下作文。文中共有10处语言错误，每句中最多有两处。每处错误仅涉及一个单词的增加、删除或修改。
增加：在缺词处加一个漏字符号（^），并在其下面写出该加的词。
删除：把多余的词用斜线（\）划掉。
修改：在错的词下面划一横线，并在该词下面写出修改后的词。
注意：
1．每处错误及其修改均仅限1词；
2．只允许修改10处，多者（从第11处起）不计分。
The first time I heard the expression "Know yourself" by Socrates, I didn't realize its meaning until I go to university. I started my university life unwillingly, because I didn't want to leave my parents and university of engineering was not my dream school, too. However, I changed my mind complete after a semester. My schoolmates are from different place, some of which are really outstanding. This makes me realized there is always someone much more better capable. Since then, to know myself has become an importance part of my life. Only by knowing who I am or where I am can I really follow the right path.
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。
On paper, Laos seems to have all to attract international tourists. It owns mighty waterfalls, golden temples and nearly two dozen national parks.
But the land-locked country welcomed only 4. 2 million visitors in 2016—a small 1.（achieve）in comparison with its southeastern Asian neighbors. In that same year, there 2.（be）32 million tourists in Thailand, 26. 8 million in Malaysia and over 10 million in Vietnam—all countries boasting their long and 3.（impress）beaches. As for Laos, its main problem is its lack of the three Ss—sun, sand and sea. 4., things seem to change now.
A high-speed rail link between Laos and China 5.（expect）to open in 2022, with the purpose of attracting more tourists.
The country is making a bold attempt to overcome this natural deficit by becoming the first foreign country to use Chinese technology, equipment and investment 6.（connect）with the giant nation's domestic fast and vast rail network.
If all goes as planned, Laos will be the first stop on one route of the Pan-Asia Railway, 7.aim is to connect China with all of Southeast Asia. With trains 8.（run） at speeds of up to 125 miles per hour, the inconvenience of carrying both passengers and cargo in the mountainous areas will be overcome 9.（great）.
If so, 10.those who enjoy hiking, now it cou ld, be the last chance to experience an undeveloped part of Southeast Asia before it joins its neighbors in boosting its tourism.
