400 million tons of plastic are generated annually, most of which comes from single-use plastic While countries are making progress in reducing this waste through paper bags and straws, there are still applications where the properties of plastic are necessary.
Transparent (透明的) wood is an alternative for such applications and is highly preferred since it prevents the harm of petroleum-derived (石油衍生的) plastic products. German scientist Siegfried Fink first created transparent wood in the year 1992, and over the past three decades it has been significantly improved by other researchers as well.
In its natural form, wood is not transparent. However, researchers have found that removing lignin, a naturally occurring biopolymer that provides structural support for the plant tissue, can make it transparent. To do so, the wood is soaked in a warm solution consisting of multiple chemicals, followed by boiling it in another solution. This removes the lignin completely and turns the wood white. However, the space that was occupied by lignin needs to be filled up to maintain structural integrity. This process is done by using a resin (树脂) at a temperature of 185 Fahrenheit (85℃).
The final product can have as much as 90 transparency, and it doesn’t break easily. More importantly, it is more biodegradable than glass or plastic.
While transparent wood isn’t commercial yet, it has been employed in a wide variety of applications ranging from construction to energy storage, making flexible electronics and packaging.
The researchers at the Indian Institute of Technology ( IIT) conducted a life-cycle analysis (LCA) of transparent wood to determine the environmental impact of its production and end-of-life (EOL) cycle. The study found that using hydrogen peroxide for delignification, followed by using epoxy for infiltration, was the most eco-friendly. When scaled up for industrial production, the former method would lower electricity consumption by as much as 98. 8 percent.
EOL analysis showed that transparent wood had a reduced ecological impact compared to polyethylene (聚乙烯), paving the way for it to be commercially adapted to replace the petroleum-based material.
1. Why is transparent wood preferred compared to plastic?| A．It is easier to make. | B．It is environmentally friendly. |
| C．It can be used longer. | D．It can be used repeatedly. |
| A．The natural form of wood. | B．The importance of chemicals. |
| C．How transparent wood is made. | D．How lignin keeps wood strong. |
| A．It can be recycled. |
| B．It will replace plastic soon. |
| C．The most eco-friendly way to produce it. |
| D．Potential damage caused by it to the environment. |
| A．Promising. | B．Difficult. | C．Profitable. | D．Uncertain. |
相似题推荐
【推荐1】When I was in school, the class I dreaded most was my eighth grade art class. The teacher put down my every attempt at completing an assignment. I simply couldn’t produce art the way she wanted it. Luckily, I’d already proven myself in other creative areas. Yet, that art teacher was successful in convincing me that I had no talent for painting, drawing, or anything related to them. Imagine my surprise when I published my nature photography and became a volunteer art teacher!
Unfortunately, my story is all too familiar to many people who come through my workshops and practice. Even more unfortunately, the vast majority of people were so discouraged in childhood that they cut off the creative impulse (冲动) in most areas of their lives. Their teachers, parents, or classmates convinced them they had no talent, so they gave up. The pain of failure was simply too great.
Why have we forgotten creativity is an experience, not a result? Let’s consider why we express creativity in first place. To be creative is to be human. Everything we’ve at our disposal (处理) is the result of someone’s creative expression and willingness to take a risk. Even so, for creativity to flower and feel free of encumbrance (累赘), it needs to be about the joyful moments spent creating, not just about what we’ve to show for those moments. Whatever pattern you need to break, try to make it about the pleasure and not about the outcome.
Therefore, I’d urge you to curb your perfectionism not enthusiasm! Perfectionism is the leading killer of artistic expression. Relax a little and bring back your childlike nature when you create. Children instinctively (本能地) know how to give over to the joy --- until someone teaches them otherwise! Let your creation be whatever it wants to be. See if it can lead you rather than the other way around. Let your unconsciousness come through, and let the expression of yourself be beautiful regardless of how it compares to anything else. After all, it’s yours, and no one but you could create it!
1. What made the author give up his dream of art? (no more than 15 words)2. What does the third paragraph mainly tell us? (no more than 10 words)
3. Please explain the underlined word “curb” in English. (no more than 5 words)
4. According to the passage, what is necessary for a creative person? (no more than 10 words)
5. Do you think you are more creative as a student? Please give an example. (no more than 25 words)
【推荐2】The Children's Climate Prize(CCP) has been given every year since 2016 to a person between the ages of 12 and 17 who has made“extraordinary efforts”to improve life on the planet for children now and in the future. Here are some of the finalists this year.
Yash Narayan
Yash Narayan,17,from California ,the US created a smartphone app called DeepWaste. Yash realized that a lot of waste could be avoided if people had a simple system for deciding what could be recycled,and what was truly garbage. Users who download the app can use their phone's camera to quickly find out the best way to get rid of something.
Fernanda Barros
Sixteen-year-old Fernanda Barros is from Pará,Brazil,where she helped start the group Fridays For Future Amazonia(FFFA). Brazil's Amazon rainforest is seriously
threatened.FFFA is working to protect the rainforest.
Lesein Mutunkei
Lesein Mutunkei,a 17-year-old from Nairobi,Kenya started a project called Trees For Goals(T4G). It encourages soccer teams to plant II trees for every goal scored
(one for each player). Already,over 1, 500 trees have been planted,and Lesein is working to spread the idea further. He would really like to get the soccer group FIFA to back the idea.
Anjali Sharma
Seventeen-year-old Anjail Shama from Melbourne,Australia took Australia's Environment Minister to court in an attempt to stop a coal mine from being expanded. The case resulted in the court saying that the government had a“duty of care”to protect young people. It has inspired others to use the courts to force action on the climate crisis.
1. Who developed a mobile application ?| A．Yash Narayan. | B．Fernanda Barros. |
| C．Lesein Mutunkei. | D．Anjali Sharma. |
| A．Set up a soccer team. | B．Expand a coal mine. |
| C．Protect the Amazon rainforest . | D．Get supporters for his project. |
| A．They are of the same age. |
| B．They care about our planet. |
| C．They are employed by the government . |
| D．They have won the Children’s Climate Prize. |
【推荐3】Will robots soon be picking soft fruits and salad?
It takes a certain skill to pick a strawberry or a salad. While crops like wheat and potatoes have been harvested mechanically for decades, many fruits and vegetables have proved resistant to automation.
But recently, technological developments and advances in machine learning have led to successful trials of more sensitive and skilful robots, which use cameras and artificial intelligence to locate ripe fruit and handle it with care and accuracy.
Developed by engineers at the University of Cambridge, the Vegebot is the first robot that can identify and harvest iceberg lettuce (莴苣)，bringing hope to farmers that one of the most demanding crops for human pickers could finally be automated.
First, there are more mouths to feed, but less manual labor. With the world’s population expected to climb to 9.7 billion in 2050 from 7.7 billion today, agriculture is under pressure to meet rising demand for food production. On top of this, growers are facing a long-term labor shortage.
Second,
| A．This is one reason behind the industry’s drive to develop robotics |
| B．there is an appeal for innovation and efficiency |
| C．robots could lead to more advanced farming practices |
| D．The development of robotics in agriculture could lead to a massive relief to the growers |
| E．They are too easily bruised (碰伤)，or too hard for heavy farm machinery to locate |
| F．This breakthrough is significant without doubt |
| G．This is partly due to a lack of interest from younger generations |
We are dealing with the results of that over-consumption in the greenest way possible, but it would be far better if we did not need to bring so much material home in the first place. The total amount of packaging increased by 12% between 1999 and 2005. It now makes up a third of a typical household’s waste in the UK. In many supermarkets nowadays food items are packaged twice with plastic and cardboard. Too much packaging is doing serious damage to the environment. The UK, for example, is running out of it for carrying this unnecessary waste. If such packaging is burnt, it gives off greenhouse gases which go on to cause the greenhouse effect. Recycling helps, but the process itself uses energy. The solution is not to produce such items in the first place.
Food waste is a serious problem, too. Too many supermarkets encourage customers to buy more than they need. However, a few of them are coming round to the idea that this cannot continue, encouraging customers to reuse their plastic bags, for example. But this is not just about supermarkets. It is about all of us.
We have learned to associate packaging with quality. We have learned to think that something unpackaged is of poor quality. This is especially true of food. But is also applies to a wide range of consumer products, which often have far more packaging than necessary.
There are signs of hope. As more of us recycle, we are beginning to realize just how much unnecessary material are collecting. We need to face the wastefulness of our consumer culture, but we have a mountain to climb.
1. The author uses figures in Paragraph 2 to show _______.
| A．the tendency of cutting household waste |
| B．the increase of packaging recycling |
| C．the rapid growth of super markets |
| D．the fact of packaging overuse |
| A．helps control the greenhouse effect |
| B．means burning packaging for energy |
| C．is the solution to gas shortage |
| D．leads to a waste of land |
| A．Unpackaged products are of bad quality. |
| B．Supermarkets care more about packaging. |
| C．It is improper to judge quality by packaging. |
| D．Other products are better packaged than food. |
| A．Fighting wastefulness is difficult. |
| B．Needless material is mostly recycled. |
| C．People like collecting recyclable waste. |
| D．The author is proud of their consumer culture. |
【推荐2】Joe got the idea to make the world a better place at school. He watched a video there concerning a factory. This factory produced a lot of trash and put it in a river. The trash and water were a bad mix. People populated the area by the river and drank its water, which made them sick. Many of them needed medicine and made regular visits to doctors.
But the video wasn't all bad news. It showed ways to pick up trash and why it's important to do this. It said people can make a difference to their environment. The video's important features made Joe associate trash with hurting people.
One day, Joe walked through a park. He recognized some of the problems from the video. One instance of these problems was the trash in the pond. It was full of plastic cups and soft drink cans. There was too much trash. Joe didn't want it to hurt anyone.
He told his grandfather about the park. His grandfather said, “You know, it's a tradition in our family to help people. That's why we give food to poor people. Maybe you can help people by cleaning the park.”
Cleaning the park would involve hard work. Joe shared the video with his relatives and friends and organized a group to help him. He chose a wide area of the park. It had the most trash. On Saturday, he gave everyone a sharp stick. They wondered why. He said, “You use the stick's tip to pick up trash. This makes it easier.” They worked for six weeks. Different people helped each time, but Joe was always there with them and told visitors there about the importance of environmental protection.
With their efforts, Joe saw a range of results. The pond was clear enough for people to swim in. Joe knew that was a good sign. He was delighted because he helped his environment.
1. What inspired the boy to clean the park?| A．The tradition of his family's love for nature. |
| B．The visit to a park with his grandfather. |
| C．The scene of people cleaning the park with sharp sticks. |
| D．The video about a factory harming a river with its trash. |
| A．By publicizing environmental protection. | B．By using the tips of sharp sticks. |
| C．By choosing a relatively clean park. | D．By asking an organization for help. |
| A．Cooperative. | B．Caring. | C．Creative. | D．Competitive. |
| A．A boy made a difference to the environment, | B．A boy recognized signs of sickness. |
| C．A video improved students' academic standards. | D．A grandfather taught his grandson traditions. |
【推荐3】The idea of billions of people going through a few masks a week during this pandemic definitely rings alarm bells, but a team of researchers in Melbourne may have the solution.
They’ve discovered that adding millions of discarded face masks to road-paving (铺路) mixtures would actually lower the cost of the road, while preventing billions of them from landfills. Just one kilometer of road would need three million masks, and the polypropylene(聚丙烯) plastic used to make single-use surgical face masks also increased the flexibility and durability of the road.
The new material is a mixture of about 2% torn masks and recycled concrete aggregate(RCA)—a material obtained from waste concrete and other minerals from destroyed buildings. This recycled material was found in the study to be ideal for two of the four layers generally required to create roadways. Paving a kilometer of two-way road with the RCA and three million face masks would result in a change of 93 tons of waste from landfills.
The final product then is more resistant to wear than asphalt(沥青), as well as being cheaper too, provided there was a method for collecting masks. The research team did a cost-analysis and found that, at $26 per ton, the RCA was about half the cost of mining raw materials, and as much as a third of the cost of shipping the used masks to a landfill.
The widespread application would be ideal for large infrastructure(基础设施) projects. For example, Washington has the 11th worst roads in terms of unaddressed repairs in the U.S. If the damaged roads in Washington state were repaired with the RCA/mask mixture, it would reuse nearly 10 billion masks, sparing American landfills hundreds of millions of tons of trash.
It’s said that the team is looking for private industry partners or governments willing to give their plastic mask road an opportunity for a large-scale test.
1. What does the underlined word “discarded” mean in paragraph 2?| A．Recycled | B．Produced | C．Abandoned | D．Mixed |
| A．2% torn masks, concrete and tons of trash. |
| B．Polypropylene plastic and building materials. |
| C．Waste concrete and other minerals from destroyed buildings. |
| D．Single-use surgical masks and recycled concrete aggregate. |
| A．To prove this material is cost-effective in paving roads. |
| B．To tell us what the team has found |
| C．To explain repairing roads costs a lot of materials |
| D．To praise the hard work the team has done. |
| A．The material used to pave roads is made of masks. |
| B．Generally speaking, it requires two layers to create roadways. |
| C．The damaged roads in Washington were repaired with the RCA. |
| D．It remains to be tested whether the solution is practical. |
【推荐1】It’s a question that has been asked for years: Is a dishwasher or washing dishes by hand greener? Which uses less energy and water?
A few years ago, the answer was that the dishwasher was better but a very careful hand-washer could probably use about the same amount of water and less energy. However, much has changed since then. Technology combined with good design has made the dish washer greatly better over the years, to the point where there’s hardly a question. Studies are showing that modern dishwashers can save more water than most hand-washers.
Dishwashers are even more efficient. Modern dishwashers have pre-heaters that increase the water temperature up to 140 degrees Fahrenheit to sanitize them. The dishwasher also has a timer that lets you set it to turn on at a later time when the power rates are lower.
On the other hand, none of the studies do an analysis of what it takes in terms of energy and water to actually build the dishwasher and replace it every 10 years or so. Nor does it take into account a Swedish study that found that children in families that wash dishes by hand are less likely to develop fever probably due to the “hygiene hypothesis”, which says the reason why kids fall ill is that their surroundings are actually too clean. If you’re not willing to fill up the sinks, the researchers point out that maybe the dishwasher is one labor-saving machine that does a better job than you can especially if you value your time. The researchers write, “When a user’s time spent washing dishes is valued, machine dishwashers pay for themselves within a year of use.”
1. Why does the author raise two questions in the first paragraph?| A．To express the author’s doubts. | B．To introduce the topic. |
| C．To show different ways to wash dishes. | D．To compare various ideas about dishwashers. |
| A．It is more environment-friendly. | B．It takes less time to wash the dishes. |
| C．It uses less water to wash the dishes. | D．It is more efficient than hand-washers. |
| A．Their effect on kids’ health. | B．Their effect on water and energy saving. |
| C．Their help in keeping the environment healthy. | D．Their help in improving kids’ health condition. |
| A．The Advantage Of The Dishwasher | B．How To Choose A Proper Way To Do The Dishes |
| C．The New Technology For Washing Dishes | D．How Dishwashers Benefit Our Lives |
【推荐2】The benefits of regular exercise are well documented but there’s a new bonus to add to the ever-growing list. New researchers found that middle-aged women who were physically fit could be nearly 90 percent less likely to develop dementia in later life, and as they did, it came on a decade later than less sporty women.
Lead researcher Dr. Helena Horder, of the University of Gothenburg in Sweden, said : "These findings are exciting because it’s possible that improving people's cardiovascular （心血管的）fitness in middle age could delay or even prevent them from developing dementia. "
For the study, 191 women with an average age of 50 took a bicycle exercise test until they were exhausted to measure their peak （最大值的） cardiovascular capacity. The average peak workload was measured at 103 watts.
A total of 40 women met the criteria for a high fitness level, or 120 watts or higher. A total of 92 women were in the medium fitness category; and 59 women were in the low fitness category, defined as a peak workload of 80 watts or less, or having their exercise tests stopped because of high blood pressure, chest pain or other cardiovascular problems.
These women were then tested for dementia six times over the following four decades. During that time, 44 of the women developed dementia. Five percent of the highly fit women developed dementia, compared to 25 percent of the women with medium fitness and 32 percent of the women with low fitness.
"However, this study does not show cause and effect between cardiovascular fitness and dementia, it only shows an association. More research is needed to see if improved fitness could have a positive effect on the risk of dementia and also to look at when during a lifetime a high fitness level is most important. " She also admitted that a relatively small number of women were studied, all of whom were form Sweden, so the results might not be applicable to other groups.
1. What is on the ever-growing list mentioned in the first paragraph?| A．Positive effects of doing exercises. |
| B．Exercises suitable for the middle-aged. |
| C．Experimental studies on diseases. |
| D．Advantages of sporty woman over man |
| A．To predict their maximum heart rate. |
| B．To assess their cardiovascular capacity |
| C．To change their habits of working out |
| D．To detect their potential health problems |
| A．It aimed to find a cure for dementia. |
| B．Data collection was a lengthy process. |
| C．Some participants withdrew from it. |
| D．The results were far from satisfactory. |
| A．More Women Are Exercising to Prevent Dementia |
| B．Middle-Aged Women Need to Do More Exercise |
| C．Fit Women Are Less Likely to Develop Dementia |
| D．Biking Improves Women's Cardiovascular Fitness |
【推荐3】One after another telecommunications giants have announced their latest fifth generation (5G) products. They have also claimed that 5G technology would be used on a massive scale by 2020. Yet, when reporting about 5G, many domestic media have described it as a"much faster" technology than 4G without mentioning any of its other advantages. As a result. the common public view about 5G is that they could "download a HD movie within one second". Beyond that, most people know nothing about 5G.
Actually, 5G technology has many more advantages than 4G apart from speed. According to the criteria of 3GPP, an international standardization organization, 5G technology can be used for at least three purposes—connecting everything, reliability of connections, and eliminating delays.
“Connecting everything” is an appropriate slogan for 5G technology, without which the Internet of Things would be impossible. 5G would enable one server to connect to multiple terminals, and thus establish high-speed coordination among them, and help the chips inside the terminals timely react to meet people’s needs. Take autonomous vehicles for example, they are mature technology products. Self-driving cars combine a variety of sensors, such as radar, computer vision, and GPS to identify navigation paths and obstacles. 5G technology will link all the elements of a transportation system, such as traffic lights, cameras and, of course, cars to establish perfect coordination so they can avoid obstacles and move on navigation paths, which will help strengthen self-driving technology.
Reliability of connections is another essential characteristic of 5G technology, whose use can be extended to other fields where high safety standards are required. For instance, in certain surgeries, surgeons insert nano-robots inside a patient’s body and have to maintain constant control over the robots to ensure they perform their functions and do not cause any harm to the patient. This is a technology that can be of great help, as it can establish reliable and continuous connections between the monitor and the nano-robots.
1. Which of the following can serve as an example of "connecting everything"?| A．Improvement of smart phone signals. | B．Decrease in telecommunication cost. |
| C．High speed in playing computer games. | D．Online tests for all members at the same time. |
| A．It can attract most eyeballs on a massive scale. |
| B．It can provide dependable and constant service. |
| C．It offers massive machine types of communication. |
| D．It employs 4G base stations and occupies less space. |
| A．Eliminating delays. | B．5G network capacity |
| C．Disadvantages of 5G | D．Building 5G base stations |
| A．5G Technology: More than about High Speed |
| B．5G Technology Will Shape the Future of Connectivity |
| C．Telecom Giants Work Together to Better 5G Technology |
| D．Advantages and Disadvantages of 5G Technology and Products |
