To tackle the problem of tiny plastics polluting waterways, chemists in the Czech Republic are thinking small. Their brainchild is a new microrobot which is no bigger than the tip of a sharpened pencil. When sunlight hits them, they produce chemical reactions that push them through water in a specific direction. When they find a piece of plastic, they stick to it and start to break it down.
Chemist Martin Pumera at the Czech University led the project. A decade ago, he chose to focus on the problem posed by microplastics. They’re everywhere—from the bottom of the ocean to air blowing onto ice atop mountains. They’ve turned up in drinking water. Some studies estimate that billions of pieces of plastic end up in the world’s waters. The plastic has many sources, from shopping bags to washing and cleaning wipes.
In lab experiments, the star-shaped swimmers stuck onto each of four different types of plastic. And after a week exposed to light, the robots had reduced the weight of the plastics. It wasn’t much—only by percent. But that was an indication that they were breaking the plastic down. They also caused the surface of the plastic to change from smooth to rough. That’s another sign that the robots were degrading (分解) it. The new study is a proof of concept type. That means it shows something can be done successfully.
In fact, Pumera says they still have a long way to go. There are many types of plastics. And even these microrobots are unlikely to succeed in degrading them all. The researchers also have not yet shown how safe this system is for the environment, although Pumera says that’s their next goal. The first real-world test will be in a wastewater-treatment plant. “Indeed,” says one researcher. “We’ll need a lot of testing to show that they’re safe in open waterways, such as at sea.”
1. The microrobots are powered by ______.| A．water | B．sunlight | C．plastics | D．pencils |
| A．The purpose of Pumera’s project. | B．The preciousness of drinking water. |
| C．The seriousness of plastic pollution. | D．The working principle of the microrobots. |
| A．The weight loss of the plastics. | B．The disappearance of the plastics. |
| C．The shape change of the microrobots. | D．The improvement in the purity of water. |
| A．Ways to Obtain Cleaner Drinking Water | B．Microrobots Invented to Treat Wastewater |
| C．New Hope for the Solution to Plastic Pollution | D．Technology Widely Applied in Environment Protection |
相似题推荐
【推荐1】How to Build a Natural Swimming Pool
Whether you like to practice your dolphin dives or lounge away the day on a raft, swimming is one of summer's perfect pleasures. With a minimum of materials and without so many chemicals, you can create a cooling summer retreat in your back yard.
Though fairly common in Europe, natural swimming pools, are in their early stage in the United States. You can ask most American swimming-pool contractors to build a backyard pool.
But in recent years, a few builders and a growing number of homeowners have learned how to build pools.
Natural swimming pools require no harmful chemicals, are fairly low-tech.
| A．The plants enrich the pool with oxygen. |
| B．Chances are that they will roll out a long list of goods. |
| C．You can make your pool as shallow or as deep as you want. |
| D．And once established, they call for only a bit of management. |
| E．It is the most ecological and economic way to build a conventional pool. |
| F．They don’t rely on a mass of manufactured materials and chemical additives. |
| G．The result is a beautiful and ecologically system that is relatively inexpensive to construct. |
【推荐2】Today's personal computers are very different from the huge machines that were born during World War II-and the difference isn't only in their size. By the 1970s, these early PCs could not perform many of the tasks that today's computers can. Users could only do mathematical calculations(数学计算) and play simple games. Today PCs are used in many different kinds of ways. At home and at work, we use our PCs to do almost everything. It is nearly impossible to imagine modern life without them.
The earliest computers were not "personal" in any way: They were large and expensive, and they required a team of engineers and other experts to keep them running. One of the first and most famous of these, the Electronic Numerical Integrator Analyzer and Computer (ENIAC), was built at the University of Pennsylvania. ENIAC cost ﹩500, 000, weighed 30 tons and took up nearly 2, 000 square feet of floor space.
ENIAC and other early computers proved that the machines were worth so much money, space and manpower they needed. For example, ENIAC could solve in 30 seconds a problem that could take a team of human "computers" 12 hours to complete. At the same time, new technologies were making it possible to build smaller computers.
But one of the most important of the inventions that make way for the PC revolution was the microprocessor(微处理器). Microprocessors were the size of a nail. They could run the computer's programs, remember information and manage data(数据) all by themselves.
These new ideas made it cheaper and easier to produce computers than ever before. As a result, the smaller, cheaper "microcomputer"-soon known as the "personal computer"-was born. Today, portable computers, smart phones and ipads allow us to have a PC with us wherever we go.
1. What's mainly talked about in the first paragraph? ______| A．An even more relaxing lifestyle without PCs. |
| B．PCs can be made full use of to do everything. |
| C．Differences between modern and early PCs. |
| D．The difficult situation of PCs being born. |
| A．It was easy to control them. | B．They took up too much room. |
| C．Nobody could afford one. | D．They were built by universities. |
| A．To predict high technology will make computers smaller. |
| B．To show computers are really smarter than human beings. |
| C．To explain why computers could deal with any problem. |
| D．To prove spending money on early computers was meaningful. |
| A．Microprocessors. | B．Programs. | C．Money. | D．Imagination. |
【推荐3】Do you have imagination? Do you like to solve problems? Can you? If so, you could be the next great inventor. “But I’m just a kid”, you might be! Don’t worry about a little thing like age. For example, one famous inventor, Benjamin Franklin, got his start when he was only 12. At that young age, he created paddles for his hands to help him swim faster. Finally his creation led to what we know is called flippers!
So you don’t have to be adult to be an inventor. One thing you do need, though, is something that kids have plenty of: curiosity and imagination. Kids are known for looking at things in new and unique ways.
So what should you do if you have what is a great idea for an invention? Talk to a friend or family member about it. Get input from others about your idea. Then ask them to help you create a working model — called a prototype (原型) of your idea.
Once you have a prototype, you can test it. Sometimes your idea turns out to be not as great as you thought. At other times, though, you realize it is a good idea and your prototype can help you figure out how to make it even better.
If your idea is really a good one, an adult can help you contact companies that might be interested in it. You will also want an adult’s help to get a patent for your idea, so that it is protected and can’t be stolen by someone else. If you need some inspiration, consider these kids and their inventions.
Jeanie Low invented the Kiddie Stool when she was just 11. It’s a folding stool that fits under the kitchen sink. Kids can unfold it and use it to reach the sink all by themselves.
At the age of 15, Louis Braille invented the system named after him that allows the blind to read.
Chelsea Lanmon received a patent when she was just 8 for the “pocket diaper (尿布)”, a new type of diaper that includes a pocket for holding baby wipes and powder.
1. By saying “But I’m just a kid”, you probably mean you _______.| A．are too young to achieve anything |
| B．can do anything though you are young |
| C．are old enough to become an inventor |
| D．have to learn knowledge from other people |
| A．would like to make friends with others |
| B．usually work hard at their lessons at school |
| C．like playing all kinds of toys at home |
| D．think about things in quite different ways |
| A．Jeannie Low. |
| B．Benjamin Franklin. |
| C．Chelsea Lanmon. |
| D．Louis Braille. |
| A．Kids have curiosity and imagination. |
| B．There are some world famous inventors. |
| C．It is possible for kids to be inventors. |
| D．Kids are exactly like adults in a way. |
【推荐1】It happens all the time: during an airport delay, a Korean perhaps starts talking to a man who might be Colombian, and soon they are chatting away in what seems to be English. But the native English speaker sitting beside them cannot understand a word.
They don’t know they are speaking Globish, the latest addition to the 6,800 languages that are said to be spoken across the world. Not that its inventor, Jean-Paul Nerriere, considers it a proper language. “It is not a language, but it is a tool, ” he says. “A language is the vehicle of a culture. Globish doesn’t want to be that at all. It is a means of communication.”
The seeds for Globish came about in the 1980’s when Nerriere was working for IBM in Paris with colleagues of about 40 nationalities. At a meeting where they were to be addressed by two Americans whose flight had been delayed, they started chatting. Then the Americans arrived and beyond their opening phrases, “Call me Jim, ”“Call me Bill, ”no one understood a word. And Jim and Bill, needless to say, did not understand the strange English spoken by others. They all spoke low-quality English. Except Jim and Bill, everyone was speaking Globish though they didn’t know it.
The main principles of Globish are a vocabulary of only 1,500 words in English, gestures and repetition. One of the interesting things in Globish is that with 1,500 words you can express everything. The target is to reach the point where you will be understood everywhere. The list goes from “able” to “zero”. “Niece and nephew, for example, are not included, but you can replace them with the children of my brother, ” Nerriere says.
But a small problem is still waiting for him. The fluent Globish speakers will not be understood by native English speakers. To this question, Nerriere responded confidently, “This is the way to get Americans to learn another language. ”
1. From the first two paragraphs, we can know that ________.| A．the Korean realizes he is speaking Globish |
| B．Globish is the working language at airports |
| C．Nerriere thinks Globish is a communication tool |
| D．the native English speaker is interested in Globish |
| A．The IBM workers in Paris couldn’t speak English at all. |
| B．Nerriere needed to keep in touch with the IBM corporation in America. |
| C．Two Americans Jim and Bill wanted to make themselves understood. |
| D．The IBM staff in Paris were from many different countries. |
| A．They might use French words instead. |
| B．They might use body language. |
| C．They might create new words. |
| D．They might consult a dictionary from “able” to “zero”. |
| A．Optimistic. | B．Cautious. |
| C．Worried. | D．Doubtful. |
He begins by reminding us of just how firmly we have been sticking to the idea of experiential learning: “Experience is respected; experience is sought; experience is explained.” The problem is that learning from experience involves （涉及） serious complications（复杂化）, ones that are part of the nature of experience itself and which March discusses in the body of this book.
In one interesting part of book，for example，he turns a double eye toward the use of stories as the most effective way of experiential learning. He says “The more accurately（精确的） reality is presented, the less understandable the story, and the more understandable the story, the less realistic it is.”
Besides being a broadly knowledgeable researcher. March is also a poet, and his gift shines though in the depth of views he offers and the simple language he uses. Though the book is short, it is demanding: Don’t pick it up looking for quick, easy lessons. Rather, be ready to think deeply about learning from experience in work and life.
1. According to the text, James March is ____________.
| A．a poet who uses experience in his writing |
| B．a teacher who teachers story writing in university |
| C．a professor who helps organizations make important decisions |
| D．a researcher who studies the way humans think and act |
| A．Stories made interesting fail to fully present the truth. |
| B．Experience makes stories more accurate. |
| C．The use of stories is the best way of experiential learning. |
| D．Stories are easier to understand when reality is more accurately described. |
| A．To explain experiential learning. |
| B．To describe a researcher. |
| C．To introduce a book. |
| D．To discuss organizational decision making. |
【推荐3】The memory of elephants is the stuff of lore (传说), and now it seems they can recall the smell of a relative even after a decade apart.
When Franziska Hörner at the University of Wuppertal in Germany and her colleagues heard about planned reunions between two mother-daughter pairs at zoos in Germany, the took advantage of the chance to test the elephants’ memories. One pair had been separated for two years, while the other had spent 12 years apart.
Hörner collected faecal (排泄物的) samples from these African elephants and others at German zoos, hauling the stinking 10-to-15-kilogram samples around in her tiny car.
Her team presented these samples one at a time to the four elephants in advance of their reunions with family members. When they encountered faeces from unrelated elephants, cither those in the same zoo or unfamiliar animals, they sniffed and walked away.
But when presented with a sample from the mother or daughter they were due to be reunited with, the female elephants repeatedly sniffed the samples and showed a variety of reactions, from making sounds to flapping their ears.
Such reactions may be linked to positive emotions, the researchers say. “That was amazing and really intense,” says Hörner. “We were sure they do remember, and they know exactly what they are smelling there.”
The sample size was small, but it would be cruel to do similar tests on elephants that weren’t being reunited, says Hörner.
“I am not surprised that elephants have memories, especially in social contexts, that last a long time,” says Joshua Plotnik at Hunter College in New York, who wasn’t involved with the work. Elephants live in groups that split up and come back together over long periods of time.
But Plotnik says the experiment may not be a true test of memory. There may be scent cues (线索，提示) common to all relatives that can trigger recognition not linked to memory, he says, and presenting the elephants with other smells would help make sense of their responses.
1. Why did Hörner collect faecal samples from elephants at German zoos?| A．To figure out mother and daughter elephants. |
| B．To haul samples in the tiny car. |
| C．To help elephants reunite with their family. |
| D．To test elephants’ memories. |
| A．They sniffed and walked away. |
| B．They responded actively. |
| C．They recognized their family members. |
| D．They showed no reactions. |
| A．There is no experimental preparation. |
| B．Samples are of different age level. |
| C．The experiment is immoral. |
| D．There are only four samples. |
| A．Drawing a conclusion according to the findings. |
| B．Making use of the findings. |
| C．Conducting further research. |
| D．Clarifying the purpose of the study. |
