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___________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________2 . The production of the cement (水泥) used in concrete is a major contributor to worldwide CO2 emissions. Since we use it a lot in building things, this is a serious problem. But there’s good news: Scientists have made a new kind of concrete that can trap CO2 instead of letting it out. It is a greener way to build things.
The concrete is made by D Company, cooperating with other companies, and is named G-concrete. Here’s how it’s made: A special cement mixture is placed in a curing chamber (养护室) and CO2 is then pumped into the chamber to be absorbed. The absorbed CO2 is then stuck inside the concrete, and will not be released. Crucially, it’s also just as strong as regular concrete.
“Generally, concrete hardens through a chemical reaction between cement and water,” the company explains. “But in G-concrete, over half the cement is replaced with a material we call γ-C2S. Instead of reacting with water, γ-C2S reacts with the CO2 in the air to harden. After mixing the materials needed to create G-concrete, the concrete can be placed in a location with high CO2 levels so it can absorb the CO2 and harden, trapping the gas inside. For example, a thermal power plant (发电厂) or other facilities that produce carbon-heavy waste gases can redirect the gases into a special chamber, where concrete products made with G-concrete can be placed to absorb the CO2 in the gases.”
Obviously, greener concrete is a good thing in itself. And under the right conditions, this could be used to create net-zero buildings, but if it’s not affordable and practical to produce, it’s not going to be widely adopted.
On that note, signs are actually quite hopeful. A representative of the company told us that the cost of producing G-concrete is about three times higher than standard concrete currently used. Work is being undertaken on further reducing this cost and the company believes it will become a lot more affordable in the near future.
1. What does the underlined word “this” in paragraph 1 refer to?A.Cement production. | B.Building construction. | C.CO2 emission. | D.Concrete use. |
A.It is environmentally friendly. | B.It is produced in thermal power plant. |
C.It is harder than regular concrete. | D.It is replaced by a cement mixture. |
A.Practical function. | B.Production cost. | C.Marketing strategy. | D.Gas emission. |
A.The Chemical Reaction Behind Concrete Hardening |
B.G-concrete: A New CO2-absorbing Building Material |
C.The Environmental Impact Of Traditional Cement Production |
D.The Economic Possibility Of The Building Material — G-concrete |
3 . Farmers have long relied on things that work without their involvement — bees to pollinate (授粉) flowers, earthworms (蚯蚓) to turn the soil, swallows to eat pests — to make sure that crops grow the right way. Now a team of British researchers is trying to take this hands-off thinking in a high-tech direction. Last October, scientists at Harper Adams University started a farm called the Hands Free Hectare to make the entire process of farming — from sowing and fertilizing to harvest — fully automatic. The project has just succeeded with five tons of robot-grown barley (大麦).
“We believe the best idea is that in the future, farmers will manage groups of smaller, autonomous machines, ” the researchers explained. “They will go out and work in the fields, allowing the farmer to use their time more effectively instead of having to drive up and down the fields.”
At the moment, agricultural machines — very large and heavy — can cover a lot of space quickly. But there are shortcomings. “Fertilizer gets sprayed over entire farms, regardless of the different needs of different crops. They’re also so heavy that they’re damaging farmers’ soils,” researcher Jonathan Gill said.
Gill and his colleagues went smaller: a tractor, a combine and a harvester, which followed a programmed route, using GPS. Altogether, they spent less than £200, 000 on equipment, and used open-source technology and a drone (无人机). Eventually the system will be complex enough to treat different parts of a field, or even individual plants, differently.
The team is quick to caution that they don’t want to put farmers out of work. They said, “Instead of being busy in the fields, the farmer will manage the machines and monitor their crops.” The next stop for the barley will be a brewery. That’s not going to be completely automatic. At least not yet.
1. What feature of bees, earthworms and swallows inspired scientists?A.Their dependence on nature. | B.Their special way of survival. |
C.Their selfless love for the earth. | D.Their natural involvement in farming. |
A.Freeing workers totally. | B.Reducing the cost of harvest. |
C.Improving the accuracy of farming. | D.Increasing the output of different crops. |
A.Gill’s project is still at the design stage. | B.Unemployment wouldn’t be a concern. |
C.The brewery will realize automation soon. | D.Complete automatic farming is unrealistic. |
A.The future of hands-free farming | B.The functions of agricultural machines |
C.The development of automatic harvest | D.The shortcomings of traditional farming |
4 . Imagine playing a racing game, using only your brain to control the complex series of turns in a lap. This is not a video game fantasy, but a real program, which engineers at the University of Texas at Austin have created as part of research into brain-computer interfaces (接口) to help improve the lives of people with motor disabilities. More importantly, the researchers combined machine learning capabilities with their brain-computer interface, making it a one-size-fits-all solution.
Typically, these devices require much calibration (校准) for each user-every brain is different, both for healthy and disabled users — and that has been a major barrier to widespread adoption. This new solution can quickly understand the needs of an individual subject and self-calibrate through repetition. That means multiple patients could use the device without needing to adjust it to the individual.
“When we think about this in a clinical setting, this technology will make it so we won’t need a specialized team to do this calibration process, which is long and boring,” said Satyam Kumar, a graduate student in the lab of José del R. Millán, a professor in the Cockrell School of Engineering’s Chandra Family Department of Electrical.“It will be much faster to move from patient to patient.”
People in the study wear a special cap with tiny sensors that link up to a computer. These sensors pick up brain waves. The sensors send brain waves to a device, which can decode brain waves and then change them into game actions.
Millán is working on ways for computers to talk to the brain. This helps people’s brains be more adaptable, meaning they can learn new things and heal after injuries. The goal is to help patients with brain problems and make using these brain-computer devices simpler and more helpful.
“The point of this technology is to help people in their everyday lives,” said Millán. “We’ll continue down this path wherever it takes us in the pursuit of helping people.”
1. Who may benefit from the brain-computer interfaces?A.People fond of video games. |
B.People working with computers. |
C.People with poor computer skills. |
D.People with limited ability to move. |
A.Their too many functions. |
B.Complex operation method. |
C.Calibration for different users. |
D.The need of an individual subject. |
A.Occupy. | B.Translate. | C.Interrupt. | D.Distract. |
A.It costs too much. | B.It is a piece of cake. | C.It takes nowhere. | D.It’s meaningful. |
5 . Resting on a branch in the dark is a Xingu screech owl with piercing eyes. Created by British artist Sarah Ball, the artwork refers to the scientific name of this species only found in the indigenous Xingu region of Brazil. The striking work is unique not just for its subject matter, but for how it was made: It was created with ash (灰烬) left behind after wildfires in the Amazon rainforest.
It’s part of a project called “From the Ashes”, an exhibition that ran in February in London. “Featuring 29 indigenous and non-indigenous artists, all the works were created using ink, colour and pastels produced from ash and charcoal (木炭),” said Migrate Art, the London-based social enterprise (企业) that created the project, whose goal is to help fix damage from the fires by raising money.
In March, the artworks were auctioned (拍卖) in London with estimates for individual pieces ranging from £2,000 to over £50,000, according to Simon Butler, founder of MigrateArt. “We keep 20% of what we make. The rest of it goes to the indigenous Xingu community, primarily for firefighting equipment,” he said.
Butler visited the Amazon rainforest two years ago. Witnessing the areas of the forest that had been burnt down, which he described as a “red desert that looked like the end of the world”, motivated him to create change through art. He collected the burnt remains of the rainforest, and shipped it back to London to be made into art materials. The materials were then sent to artists around the world. British artist Piers Secunda used black ink to create a painting titled Smoke In The Jungle. The collection also includes works made by members of the indigenous community.
“The sale of my work to help the Xingu Reserve buy firefighting equipment to extinguish Amazon fires is the best use of my time and resources that I can imagine,” said Secunda. “These art advocacy actions are grains of sand which build a pile. For now, the pile is small, but it is growing and will become substantial.”
1. What is the author’s purpose of describing the artwork in paragraph 1?A.To detail the artist’s motivation. | B.To discuss climate change effects. |
C.To highlight its unique creation method. | D.To provide insights into a new bird. |
A.They will be stored by Simon Bulter. |
B.Migrate Art will cooperate with more artists. |
C.Artists will make more contribution to the poor. |
D.Indigenous Xingu community will afford firefighting equipment. |
A.By visiting Amazon rainforest. | B.By watching relevant information. |
C.By talking with rainforest protectors. | D.By appealing to artists to create related works. |
A.Promising. | B.Uncaring. | C.Demanding. | D.Controversial. |
The problem with
So we set out to find out
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Frances Wood, a former head of the Chinese section at the British Library
1. What should the listeners bring on Monday?
A.Food. | B.A jacket. | C.Drinks. |
A.Cycle to the mountaintop. | B.Enjoy the fantastic views. | C.Cycle to the camp. |
A.On Tuesday. | B.On Wednesday. | C.On Thursday. |
A.To the beach. | B.To the observatory. | C.To the factory. |
1. What place is the man interested in?
A.The hotel. | B.The gas station. | C.The coffee houses. |
A.A gas station. | B.A school. | C.A park. |
A.500 meters. | B.200 meters. | C.100 meters. |
1. When does the conversation take place?
A.At the beginning of a term. |
B.In the middle of a term. |
C.At the end of a term. |
A.He can’t finish his paper. |
B.He did badly in chemistry. |
C.He failed a physics test. |
A.Join a study group. |
B.Drop out of the physics class. |
C.Ask Professor Smith for help after school. |
1. What is the probable relationship between the speakers?
A.Manager and worker. | B.Fellow workers. | C.Husband and wife. |
A.She is a difficult person. |
B.She seems bad-tempered. |
C.She is easy to get along with. |