When a laptop or smart phone battery starts losing is power, the only options are to buy an expensive replacement or just keep it plugged in all the time. But a woman Mya Le Thai may have found the solution to this problem.
Thai was frustrated that the batteries for her wireless devices degraded (退化) over time, until they failed to charge fully. She did not like having to keep her laptop connected to an electrical outlet to keep it powered on. So, she decided to do something about that problem. At first, she and her team at UC Irvine thought about inventing a new battery. But as they experimented, Thai discovered something that might permit lithium-ion (锂离子) batteries to last forever.
Lithium-ion batteries power most wireless devices. Over time, the batteries lose the ability to hold a charge. Most of these batteries have a lifespan of about 7,000 charging cycles before they die. One of the reasons lithium-ion batteries degrade is their use of nanowires to carry electricity. Nanowires are extremely thin. A human hair is thousands of times thicker, for example. Nanowires are extremely efficient carriers of electricity, which makes them useful in batteries.
But, Thai had a theory-the nanowires might last longer if covered with a gel (凝胶). She and her team tested his theory. “It was a long process and a lot of work,” Thai said. The team tried many coverings for the wires. PMMA, a type of plastic, was one of them. The nanowires were coated with PMMA and cycled through charging 200.000 times. The PMMA coated nanowires showed no evidence of damage. The results suggest that batteries could last forever without losing charging ability.
Thai hopes to continue her research to understand why this gel works so well and to see if any other gel could create better results and she is enjoying the publicity about her discovery. She said she never expected her research to get media coverage. “It’s kind of cool,” she said. “I’m really glad people are showing interest in my work and not just in the work itself but also in technology and energy.”
1. Why did Mya Le Thai work on lithium-ion batteries?| A．She disliked the batteries for her laptop. |
| B．Her team were ordered to invent a new battery, |
| C．The batteries would soon fail to get fully charged. |
| D．Many people thought batteries were too expensive. |
| A．They are too weak to carry electricity. |
| B．They are not suitable to use in batteries. |
| C．They last exactly 7,000 changing cycles. |
| D．Their thinness is a cause of batteries degrading. |
| A．Mya Le Thai Discovered Nanowires |
| B．A Woman Invents a Lasting Battery |
| C．The Options of Batteries for Wireless Devices |
| D．The Reasons for Batteries Degrading |
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【推荐1】Dogs can tell how other dogs are feeling from the way their tails are wagging (摇摆), according to researchers who monitored the animals’ heart rate as they watched dogs’ movies. The Italian team found that dogs had higher heart rates and became more anxious when they saw others wag their tails more to the left, but not when they wagged more to the right, or failed to wag at all.
The curious form of communication is probably not intentional, or consciously understood, but is instead an automatic behavior that arises from the structure of the brain, said Giorgio. “It’s not something they clearly and exactly understand,” Giorgio told The Guardian. “It’s just something that happens to them.”
Giorgio traces the effect back to the way the two halves of the brain process different experiences. In a previous study, his team showed that when a dog had a positive experience, activity rose in the left side of the brain, bringing about more tail wagging to the right. Or else more tail wagging to the left. The effect is barely visible to the human eye because dogs tend to wag their tails too fast, but it can be seen with slow motion video, or in some larger types.
In the latest study, the researchers wanted to find out whether the direction of tail wagging had any effect on other dogs. To get an answer, they fitted dogs with vests that recorded their heart rates, and played them movies of other dogs wagging their tails one way and then the other. To ensure the dogs reacted only to tail wagging, and not appearance, they repeated the experiment with dogs that appeared only as shadows.
“When dogs saw other dogs wagging their tails to the right, there was quite a relaxed reaction and no evidence of an increased heart rate. But when the wagging was to the left we saw an increase in heart rate and a series of behaviors typically associated with stress, anxiety and being more watchful,” Giorgio said. The anxious animals held their ears up, breathed, and kept their eyes wide open. The study appears in the latest issue of Current Biology.
1. What does the text focus on?| A．Animal protection. | B．Animal psychology. |
| C．Animal tests. | D．Animal welfare. |
| A．Their automatic behavior. | B．Their conscious response. |
| C．Their increasing heart rate. | D．Their selective preference. |
| A．When they run quickly. | B．When they feel hungry. |
| C．When they feel stressed. | D．When they play with their owners. |
| A．Giorgio did the research on his own. |
| B．The effect of dog’s wagging tails can be seen by human eyes. |
| C．A dog keeping his eyes wide open may show he is nervous or worried. |
| D．The findings of the study will help with wildlife protection. |
【推荐2】Climate change, not human hunting, may have destroyed the thylacine(袋狼) , according to a new study based on DNA from thylacine bones.
The meat-eating marsupials (有袋动物) died out on mainland Australia a few thousand years ago, but survived in Tasmania, an island of southeast Australia separated from the mainland, until the 1930s. Until now, scientists have believed the cause of this mainland extinction was increased activity from native Australians and dingoes (Australian wild dogs).
Scientists behind the University of Adelaide study, which was published in the Journal of Biogeography on Thursday, collected 51 new thylacine DNA samples from fossil bones and museum skins. The paper concluded that climate change starting about 4,000 years ago was likely the main cause of the mainland extinction.
The ancient DNA showed that the mainland extinction of thylacines was rapid, and not the result of loss of genetic diversity. There was also evidence of a population crash in thylacines in Tasmania at the same period of time, reducing their numbers and genetic diversity.
Professor Jeremy Austin said Tasmania would have been protected from mainland Australia’s warmer, drier climate due to its higher rainfall. He argued that climate change was “the only thing that could have caused, or at least started, an extinction on the mainland and caused a population crash in Tasmania.”
“They both occurred at about the same time, and the other two things that have been talked about in the past that may have driven thylacines to extinction on the mainland were dingoes and humans. So the only explanation that’s left is climate change. And because that population collapse happened at the same time that the species went extinct on the mainland, our argument is there’s a common theme there and the only common theme is that there is this change in climate.”
1. What did scientists believe in the past according to the passage?| A．Marsupials were all meat-eating animals. |
| B．Dingoes should be removed from Australia. |
| C．Thylacines had no enemies on mainland Australia. |
| D．Human activities may cause the extinction of thylacines. |
| A．Tasmania has more dingoes. |
| B．Tasmania has more native activities. |
| C．Tasmania has a higher temperature. |
| D．Tasmania has more rainy days. |
| A．change | B．aging | C．decline | D．increase |
| A．The result of warmer climate in Australia |
| B．The ways of protecting meat-eating animals |
| C．The cause of disappearance of thylacines |
| D．The effect of climate change on wildlife |
【推荐3】Researchers say they have discovered new evidence that Mars once had a large northern ocean. The finding adds to existing evidence that ancient Mars had the right conditions to possibly support some form of life.
Today, Mars has a cold, desert climate. Any water is believed to be in the form of ice because of the planet’s extremely cold temperatures. But there is a rich amount of evidence suggesting that rivers, lakes and even oceans once existed on Mars. For example, a 2015 study by the American space agency NASA suggested that 4.3 billion years ago, Mars likely had an ocean that covered nearly half of Mars’ northern hemisphere (半球).
Another NASA-supported study, published in January, estimated that 3 billion years ago, the climate in much of the planet’s northern hemisphere bore a striking likeness to the present Earth. The study noted that at the time, Mars likely had a much thicker air than today and had an active, northern ocean.
Now, two American researchers have announced a set of maps, which provide new environmental evidence of a large ancient ocean on Mars’ low-lying northern hemisphere.
The scientists say the ridges (山脊) likely represent the leftover evidence of eroded (被侵蚀的) river systems and an ancient ocean floor. The team said its research also suggested the existence of remains, providing further evidence of a large ocean.
Cardenas added that areas on our own planet containing water-formed ridges and remains provide researchers with much useful information about an area’s climate and life forms. “If scientists want to find a record of life on Mars, an ocean as big as the one that once covered Aeolis Dorsa would be the most reasonable place to start,” he said.
In addition to providing more evidence of a large ocean, Cardenas suggested the new study also provides useful information on Mars’ ancient climate and developmental history. “Based on these findings, we know there must have been a period when it was warm enough and the atmosphere was thick enough to support this much liquid water at one time,” he said.
1. What was once similar to the present Earth in the ancient times for Mars?| A．Its climate. | B．Its structure. | C．Its speed. | D．Its creatures on it. |
| A．They drew the ancient oceans on Mars. |
| B．They found the lost waters of the ancient ocean. |
| C．They discovered signs left by the ancient sea. |
| D．They found evidence by studying areas on earth. |
| A．Temperature changes. | B．Warm environment. |
| C．Regular rains. | D．Extreme weather. |
| A．Warning from Present State of Mars |
| B．History of Climate Development on Mars |
| C．Secrets of Life on Mars Discovered |
| D．New Evidence of a Large Ancient Ocean on Mars |
【推荐1】Exploring unmapped territory on the moon could soon be as easy as slipping on a backpack. NASÁ researchers and their partners have developed a high-tech pack to aid explorers in the most remote wilderness imaginable: the airless wastes at the South Pole of the Moon.
The pack, dubbed the Kinematic Navigation and Cartography Knapsack (KNaCK), is a remote-sensing mapping system. Shaped like a hiker’s backpack, it makes use of an innovative type of lidar (激光雷达) called frequency modulated continuous wave (FMCW) lidar to provide Doppler velocity and range for millions of measurement points per second. These measurement points instantly create a real-time navigation system, delivering to the explorer a 3D high-resolution map of the surrounding area.
“As human beings, we tend to locate ourselves based on landmarks—a specific building, a bunch of trees. Those things don’t exist on the Moon. With KNaCK continuously showing in real time how far they’ve gone and how far is left to go to reach their destination, explorers can cross the surface boldly without having to worry about their safety. They can even mark specific sites where they found some unique mineral or rock formation, so others can easily return for further study,” said Dr. MichaelZanetti, who leads the KNaCK project at NASA’s Marshall Space Flight Center in Huntsville, Alabama.
That’s vital for astronauts on a clock, their exploration limited by the oxygen supply in their suits. KNaCK’s ultra-high-resolution precision—an order of magnitude greater than conventional lunar topography map(地形图)and elevation models makes it a vital resource for conducting science and mission operations 238,900 miles away from mission control, Zanetti said.
Currently, the backpack prototype (原型) weighs about 40 pounds. When it comes to the work to be done next, Zanetti said, Taking advantage of the latest advancements in lidar technology from Aeva, we will make our next-generation device about the size of a soda can, and harden the sensitive electronics against the punishing effects of microgravity and solar radiation.” He looks forward to mounting it on a rover (探测器) or on the side of an astronaut’s helmet, which should leave plenty of room in future lunar mountaineers’ all-purpose backpacks.
1. What does Paragraph 2 mainly talk about?| A．The working principle of KNaCK. | B．The problems with the FMCW lidar. |
| C．The possibility of exploring the moon. | D．Explorers’ expectations for the mapping system. |
| A．setting a good example to others | B．providing convenience for others |
| C．warning others of possible dangers | D．avoiding getting lost in strange places |
| A．Produce all-purpose backpacks. | B．Reduce the size of the backpack. |
| C．Seek help from the government. | D．Make the hardware more sensitive. |
| A．The achievements of moon exploration. | B．The challenges faced by moon explorers. |
| C．A new device for future moon explorers. | D．A new way to conduct research on the moon. |
【推荐2】A unique curved (弯曲的) barrier has been designed by researchers at Imperial College London, who publish new findings in the journal Cities & Health on how the structure can protect people from the damaging effects of air pollution.
The health concerns arising from lower air quality are more significant amongst lower-income communities which are more likely to be near roads with heavy traffic. Similarly, children are more readily exposed (接触) to air pollution simply because they live closer to the ground, where heavier pollutants settle over time.
Dr Tilly Collins from Imperial’s Centre for Environmental Policy found this issue particularly worrying, especially after noticing the severe pollution in the air while watching her child playing netball in a school playground alongside a busy London A-road. “I started researching the effect of walls along roads.” Dr Collins said. “It became evident that along the pedestrian (行人的) side of these roadside walls, there are vortexes (涡旋) where the air quality can actually be even worse as the pollutants get trapped in them.”
Initially building off simple models, Dr Collins and Dr Huw Woodward, also from the Centre for Environmental Policy, explored ideas of urban design that would mitigate these vortex effects and improve air quality for pedestrians and especially children.
Inspired by sound-walls alongside motorways in Germany and the Netherlands, the researchers found that curved structures would more effectively reflect pollutants back towards the roads and would very rapidly improve air quality for pedestrians in an inexpensive manner.
When asked about the challenges faced during this project, Dr Collins said: “Initially, it was difficult to convince others to get on board. The focus is very much on successfully reducing smoke from cars, but there are things we can do now to protect our children.”
“With increased attention being placed on the challenges associated with air pollution, there is a need for unique and effective urban design, and these curved barriers are able to handle these challenges head on, providing huge benefits to the general public,” said Marcus Grant, editor in chief of Cities & Health.
1. Why are children more likely to be victims of air pollution?| A．They are shorter in height. | B．They have bigger airways. |
| C．They tend to breathe more slowly. | D．They like playing near busy roads. |
| A．Monitor. | B．Reduce. | C．Predict. | D．Explain. |
| A．It can reduce smoke from cars greatly. |
| B．It can benefit urban traffic in some way. |
| C．It can limit pedestrians’ exposure to poor air. |
| D．It can be used as sound-walls alongside motorways. |
| A．It needs more attention from the public. | B．It might come across many challenges. |
| C．It is very likely to have a bright future. | D．It should be expanded in more industries. |
【推荐3】One in three UK consumers throw away food just because it reaches the use-by date (使用期限), but 60% of the food we throw away each year is safe to eat.
In order to help detect spoilage (变质) and reduce food waste for supermarkets and consumers, researchers have developed spoilage sensors for meat and fish packaging. The researchers say the sensors could also finally replace the use-by date — a widely used indicator of being fresh and eatable.
The sensors cost two US cents each to make. Known as “paper-based electrical gas sensors (PEGS)”, they detect spoilage gases in meat and fish products. The information provided by the electronic nose is received by a smartphone, and then you can know whether the food is fresh and safe to eat.
The researchers made the sensors by printing carbon electrodes (电极) onto a special type of paper. The materials are eco-friendly and harmless, so they don’t damage the environment and are safe to use in food packaging. The sensors, combined with a tiny electronic system, then inform nearby mobile devices, which identify and understand the data about spoilage gases.
Lead author Dr. Firat Guder of Imperial’s Department of Bioengineering said, “Although they’re designed to keep us safe, use-by dates can lead to eatable food being thrown away. They don’t always reflect its actual freshness. In fact, people often get sick from food-borne diseases due to poor storage, even when an item is within its use-by date. These sensors are cheap enough, so we hope to see supermarkets using them within three years. Our goal is to use PEGS in food packaging to reduce unnecessary food waste.”
1. What is the purpose of PEGS?| A．To test the freshness of food. | B．To make food taste better. |
| C．To help supermarkets store food. | D．To keep the meat and fish fresh. |
| A．They are made of special paper. | B．They don’t produce pollution. |
| C．They are built in mobile devices. | D．They directly show people information. |
| A．They are not completely reliable. |
| B．They determine the freshness of food. |
| C．They can help reduce food waste. |
| D．They help prevent food-borne diseases. |
| A．The process of developing spoilage sensors. |
| B．A new device in packaging to reduce food waste. |
| C．The application of spoilage sensors in food processing. |
| D．Use-by dates’ influence on supermarkets and consumers. |
【推荐1】We usually think of archaeology as involving brave explorers and lots of painstaking digging. But today, long-hidden cities are being revealed from the air, where modern archaeologists use laser beams to spot evidence of ancient life buried beneath thick vegetation.
Lidar, short for “light detection and ranging” (and a cousin of radio-based radar), involves directing a rapid succession of laser pulses at the ground from an airplane or a drone. Software captures the time and wavelength of the pulses reflected from the surface and combines it with GPS and other data to produce a precise three-dimensional map of the landscape below. These high-tech explorations have revealed long-buried Mayan cities.
In recent years, lidar has exposed a sprawling ancient city in western Mexico called Angamuco, The discovery of this long-lost Mexican large city is especially significant. Built by the Pur pecha, Angamuco was a major civilization in the early 16th century, before Europeans arrived. The city extended over ten square miles before it was covered by a lava flow. That is a huge area with a lot of people. There are about 40, 000 building foundations there, which is about the same number of building foundations that are on the island of Manhattan. The Pur pecha’s main buildings were loosely sited in eight zones around the edges rather than being located in one large center.
“To think that this massive city existed in the heartland of Mexico for all this time and nobody knew it was there is amazing,” says Chris Fisher, an archaeologist who led the expedition.
The revelation of Angamuco is a prime example of the power and promise of lidar. Archaeologists discovered signs of the buried city in 2007 and initially attempted to explore it using a traditional “boots on the ground” approach. But the team soon realized that with the rugged terrain, it would take at least a decade to outline the entire massive city.
In 2011, they began using lidar to map nearly 14 square miles, revealing many astonishing features, from pyramids and temples to road systems, garden areas, and even ball courts. This gave them the “map” they needed to know where to explore further. So far, Fisher and his team have verified more than 7,000 architectural features over a 1.5-square-mile area. The earliest artifacts include ceramic fragments and other remains dating as far back as AD 900.
All told, researchers now believe that more than 100, 000 people lived in Angamuco from about AD 1000 to AD 1350. That makes it the biggest city in western Mexico at the time-or at least the biggest city we know about so far.
“Everywhere you point the lidar instrument, you find new stuff,” says Fisher. “Right now, every textbook has to be rewritten, and two years from now, they’re going to have to be rewritten again.”
1. __________may be necessary aids when lidar is used.| A．GPS, software and laser pulses | B．A drone, radar and a map |
| C．An aeroplane, software and GPS | D．A drone, an aeroplane and a map |
| A．planned in a detailed way | B．spreading in an untidy way |
| C．massive but well-designed | D．long-buried but well-preserved |
| A．Angamuco was the first ancient city discovered with radar. |
| B．The area of the city was as big as that of the island of Manhattan. |
| C．Angamuco was probably the biggest city in westen Mexico at that time. |
| D．The rugged terrain in Angamuco prevented the explorers from using radar. |
| A．Lidar has been widely accepted by the archaeologists in western Mexico. |
| B．The current knowledge about the city of Angamuco might be out of date. |
| C．But for lidar it would be impossible to know what the city of Angamuco looked like. |
| D．The archaeologists spent almost ten years exploring Angamuco using traditional tools. |
【推荐2】Today, being freelancers (自由职业者) is one of the most powerful trends in the way we work. According to a current study, there are 70.4 million freelancers in the US. By 2028, this number will increase to 90.1 million, or54% of the workforce, basically divided equally between genders.
It would appear to be solid guidance in today’s modern workforce to tell some one who wants the “3Fs”— flexibility, fulfillment, and financial independence — to “just go freelance”, right? The large numbers and data support this direction and suggest that it could be regarded as safe and wise advice.
However, telling someone who is unhappy in their current professional situation to “just go freelance”, is like telling them to climb Mt Qomolangma without oxygen: 5% of climbers have succeeded, so it can be done, but there will be hardship and a much higher chance of failure. Just as one should weigh the risks of attempting to climb the 8848.86m mountain without essential supplies, the idea of being freelancers must be truly understood.
The number is increasingly growing, however, actually three quarters of self-described freelancers in the USare part-time, meaning the vast majority are using freelance work as a side hustle (副业). What’s more, research shows that 70% of full-time freelancers participated in upskilling training. Besides, more than half (58%) of freelancers have experienced non-payment from clients, and most do not have retirement plans or affordable health insurance. Many freelancers fail after the first year as a result of making avoidable mistakes with only a third making it.
We can’t simply tell people to “just go freelance” unless we also tell them to invest in training and cooperate with like-minded, supportive communities to strengthen industry rights before they start their journey to the summit as an individual, but never alone.
1. Which of the following is NOT a benefit as a freelancer?| A．Flexible schedule. |
| B．Safer environment. |
| C．Less financial reliance. |
| D．A sense of achievement. |
| A．To indicate a bright future of freelancers. |
| B．To show the determination of freelancers. |
| C．To highlight the challenge of reaching the top. |
| D．To emphasize the importance of weighing risks. |
| A．Concerned. | B．Supportive. | C．Understandable. | D．Ambiguous. |
| A．Most of the freelancers meet with failure. |
| B．Many Americans choose to be freelancers. |
| C．Being a freelancer is not as easy as imagined. |
| D．Going freelance brings us a promising future. |
【推荐3】With the widespread use of smartphones, emojis(表情符号)have become a popular medium for expressing emotions and ideas. Researchers now believe these expressive symbols can play a significant role in medicine, increasing the response rate of health surveys(调查).
Scientists say that employing emojis in healthcare communications has several benefits, such as general recognition across diverse populations. So the study authors strongly support the use of emojis to bolster communication between patients and physicians.
“By promoting more effective communication between patients and care providers, as well as between physicians themselves, an emoji-based language system with a common agreement of meanings can be developed,” says Professor Kendrick Davis, who is an associate professor at the UCR School of Medicine. The professor has been working on creating an emoji-based measurement system for the past two years. And he has even conducted a study using emojis to measure health among college students.
Davis further explains that a significant part of medical communication includes surveys, which are often areas of communication breakdown. “Surveys are usually passed to patients in a variety of different stages of their care. But many surveys are explained with language that can introduce an obstacle. This is where emojis, which are friendly and widely used, come into play by replacing survey language that can be hard for some patients to understand,” he says. The authors also point out that while effective communication is important for successful treatment and care, certain health conditions such as brain injury can cause major obstacles. In such cases, emojis could be helpful.
However, Davis also acknowledges the importance of qualitative(定性的)methods. He expresses an interest in partnering researchers whose methodologies are heavily qualitative.
1. Why does the author mention the use of smartphones in paragraph 1?| A．To introduce the functions of emojis. |
| B．To explain why emojis develop fast. |
| C．To tell us where emojis are mainly used. |
| D．To show emojis have become widely used. |
| A．Improve. | B．Start. | C．Predict. | D．Suggest. |
| A．Emojis shouldn’t be used in letters from doctors. |
| B．Physicians are poor at communicating with patients. |
| C．Major obstacles can be caused by emojis sometimes. |
| D．Emojis can help patients finish medical surveys better. |
