“Ladies and gentlemen, welcome aboard NASA’s Space Elevator. We’re going to leave soon. The entire ride will take about five hours, so sit back and enjoy the trip.”
Does this sound like the Sci-Fi Channel? Well, it’s not. Although space elevators are often considered as a science fiction dream, I believe they will exist soon—perhaps in two or three decades.
Throughout my career as an aerospace engineer and physics professor, I keep coming back to the concept of a cable stretching from Earth to space, along which people and cargo can easily travel. In recent years I and other researchers have found new ways to tinker with designs and answer questions about how space elevators could work.
There are many reasons to build a space elevator. The obvious one is the major energy and cost savings; it’s a much more practical way to get to orbit than rockets. Another reason that is often overlooked is accessibility. The word “space mission” would be replaced by “transit,” as trips to space become routine and mostly independent of weather conditions. Transits involving humans would be safer than current practices, whereby astronauts must accept an enormous risk to their lives with each launch. A space elevator becomes a bridge to the entire solar system. Release a payload in the lower portion, and you orbit Earth, but do so in the upper portion, and you orbit the sun; all without fuel.
Although I may come across as a space elevator advocate, the truth is, I simply enjoy studying their mechanics. In a world with monumental problems, dreaming of such projects allows me to envision a scenario where we have become responsible custodians (守护者) on this planet.
1. What’s the function of Paragraph 1?| A．To introduce the topic. | B．To set a background. |
| C．To make a comparison. | D．To give an example. |
| A．Abandon. | B．Improve. | C．Establish. | D．Discuss. |
| A．To please science fiction fans. | B．To promote space tourism. |
| C．To protect astronauts’ safety. | D．To make space travel easier. |
| A．Unclear. | B．Doubtful. | C．Optimistic. | D．Dismissive. |
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【推荐1】Making beers on the moon might seem like a pipe dream to many, but for a group of students from the University of California at San Diego, there is a chance to take their research beyond Earth’s surface.
The Lab2Moon competition, held by TeamIndus, is offering students the chance to secure a spot on the TeamIndus rocket this year.
Taking craft beer to the next level, the students want to test whether it’s possible for yeast(酵母)to work and create beer on the moon. However, they believe the experiment is not just a creative concept for astronauts, it’s also important for the development of drugs and yeast-containing food, like bread.
“The idea started out with a few laughs among a group of friends,” said Neeki Ashari, a fifth-year bioengineering students at UC San Diego. “We all appreciate the craft beer, and we were excited to learn that there was an opportunity to design an experiment that would go up on India’s moonlander, we thought we could combine our hobby with the competition by focusing on the practicality of yeast in outer space.”
The preparation work for the beer-up to the stage of adding yeast-will all be done on Earth, and rather than separating the fermentation (发酵)and carbonation stage of making beer, the team plans to combine them.
This removes the need to release CO2 accumulated in the process, which may result in cleanliness and safety issues out in space.
If selected, Team Original Gravity will be the first to make beer in outer space, and the fermentation will take place in a container no bigger than a soda can.
All teams competing for the place will showcase their ideas in Bangalore, India, in March.
Sadly, you won’t be enjoying moon beer in you local craft beer bar anytime soon, as no samples will be brought back. However, this small experiment could provide important data on just how practical it is for us to make and create our own resources on other planets and moons by learning how consumables(消耗品) behave in different environments.
1. How did the students feel when they heard of the chance to design the experiment?| A．Confident. | B．Nervous. |
| C．Thrilled. | D．Casual. |
| A．Adding yeast on Earth. | B．The mixing of two stages. |
| C．The preparation work on Earth. | D．Fermentation and carbonation. |
| A．It has been designed based on similar experiments. |
| B．It’s quite competitive compared with other designs. |
| C．Its process was adapted to make it safer and greener. |
| D．Its design has already been approved by TeamIndus. |
| A．It seems like a pipe dream. | B．It’s extremely complicated. |
| C．It’s creative but impractical. | D．It’s meaningful and hopeful. |
【推荐2】Four Coolest Inventions From the 2024 Consumer Electronics Show
The annual Consumer Electronics Show is upon us. This year is as sci-fi cool as always with various innovative inventions. Here we’ve chosen four to share with you.
Smart Mirror
How do you feel when you look into the mirror in the morning? Paris-based company Baracoda says its BMind Smart Mirror can take a look and tell how you’re feeling. The technology uses artificial intelligence (AI) and natural language processing to analyze expressions and gestures and then provides guided meditations (冥想) and light therapy. The mirror can also guide you through tooth brushing and analyze your skin’s needs.
Ampera
LifeSpan’s Ampera Bike combines the health benefits of a pedal desk with the energy savings of a body-powered phone charger. A half-hour of pedaling can charge the average phone about 50 percent and cycling over 60 revolutions (转数) per minute can charge a laptop. The bike allows workers to complete the same tasks as they did sitting still while enjoying the physical and mental benefits of staying active.
Squad Mobility’s Electric Vehicle (E. V.)
On roads crowded with ever-bigger trucks and cars, Squad Mobility’s tiny solar-powered E. V. almost looks like a children’s toy. In a sunny environment, the 6.6-foot-long car can go about 13 miles just on solar charge from its 250-watts-peak rooftop panel (面板); it can also be plugged in like a regular E. V. With top speeds around 25 miles an hour, the car could be used to make a short commute (通勤).
Delta Pro Ultra
Power failure is annoying and can even be dangerous. Delta Pro Ultra from EcoFlow is a backup battery generator that runs on solar power, keeping houses powered in emergencies. At 186 pounds, it’s portable enough to hit the road, powering recreational vehicles or tiny homes.
1. Whose product can offer analyses about its user’s skin?| A．Squad Mobility’s. | B．Baracoda’s. |
| C．EcoFlow’s. | D．LifeSpan’s. |
| A．They will become more confident. | B．Their mental pressure can be relieved. |
| C．Their phones can save more power. | D．They will have more physical activity. |
| A．They can be used for a long travel. | B．They are intended for emergencies. |
| C．They involve the use of solar energy. | D．They are based on AI technology. |
【推荐3】A robot created at Stanford University in California is diving down to shipwreck and sunken (沉没的) planes in a way that humans can’t do. Known as OceanOneK, the robot allows its operators to feel like they’re underwater explorers, too.
OceanOneK is similar to a human diver from the front, with arms and hands and eyes that have 3D vision, capturing the underwater world in full color. The back of the robot has computers and eight multi-directional thrusters (推进器) that help it carefully explore the sites of fragile sunken ships. When an operator at the ocean’s surface uses controls to direct OceanOneK, the robot’s touch-based feedback system causes the person to feel the water’s resistance as well as the forms of artifacts (人工制品).
OceanOneK’s realistic sight and touch capabilities are enough to make people feel like they’re diving down to the depths-without the dangers or immense underwater pressure a human diver would experience.
The idea for OceanOneK came from a desire to study coral reefs in the Red Sea at depths beyond the normal range for divers. While OceanOneK was designed to reach maximum depths of 656 feet, researchers had a new goal: 1 kilometer, hence the new name for OceanOneK.
The researchers changed the robot’s body by using special foam (泡沫) to increase buoyancy (浮力)and fight the pressures of 1,000 meters-more than 100 times what humans experience at sea level. OceanOneK also got two new types of hands and increased arm and head motion.
During OceanOneK’s deep dive in February, team members discovered the robot couldn’t rise when they stopped for a thruster check. Floatation on the communications and power line had collapsed, causing the line to pile on the top of the robot.
They were able to pull the loose parts, and OceanOnek’s going down was a success. It dropped off a memorial marker on the seabed that reads, “A robot’s first touch of the deep seafloor-A vast new world for humans to explore.”
Khatib, a professor, called the experience an “incredible journey”. “This is the first time that a robot has been capable of going to such a depth, interacting with the environment, and permitting the human operator to feel that environment,” he said.
1. What can we know about OceanOnek?| A．It works underwater with remote control. |
| B．It works underwater like a human diver. |
| C．It can repair fragile sunken ships underwater. |
| D．It can make human divers work better underwater. |
| A．The failing experience of previous experiments. |
| B．The eager desire of deep sea exploration. |
| C．The academic research into treasures from shipwrecks. |
| D．The inspiration from coral reefs in deep oceans. |
| A．Failure to go up normally. |
| B．Loss of touch with the operators. |
| C．Floatation with sea current. |
| D．Collapse of a thruster at the seafloor. |
| A．Robots help people become ocean explorer. |
| B．Robots explore shipwrecks on the ocean bottom. |
| C．Robots search the ocean floor for sunken treasures. |
| D．Robots dive into the deep ocean to locate minerals. |
【推荐1】Reading can be a social activity. Think of the people who belong to book groups. They choose books to read and then meet to discuss them. Now, the website Book Crossing.com turns the page on the traditional idea of a book group.
Members go on the site and register (登记) the books they own and would like to share. Book Crossing provides an identification number (识别码) to stick inside the book. Then the person leaves it in a public place, hoping that the book will have an adventure, traveling far and wide with each new reader who finds it.
Bruce Pederson, the managing director of Book Crossing, says, “The two things that change your life are the people you meet and books you read. Book Crossing combines both.”
Members leave books on park benches and buses, in train stations and coffee shops. Whoever finds their book will go to the site and record where they found it.
People who find a book can also leave a journal entry describing what they thought of it. E— mails are then sent to the BookCrossers to keep them updated about where their books have been found. Bruce Pederson says the idea is for people not to be selfish by keeping a book to gather dust on a shelf at home.
Book Crossing is part of a trend (趋势) among people who want to get back to the “real” and not the virtual (虚拟).The site now has more than one million members in more than one hundred thirty—five countries.
1. Why does the author mention book groups in the first paragraph?| A．To explain what they are. | B．To introduce Book Crossing. |
| C．To stress the importance of reading. | D．To encourage readers to share their ideas. |
| A．An adventure. | B．A public place. |
| C．The book. | D．The identification number. |
| A．Keep it safe in his bookcase. | B．Mail it back to its owner. |
| C．Meet other readers to discuss it. | D．Pass it on to another reader. |
| A．Online Reading: A Virtual Tour | B．Electronic Books: A New Trend |
| C．A Book Group Brings Tradition Back | D．A Website Links People through Books |
【推荐2】Wearing ties (领带) was originally the mark of Britain’s most powerful classes. That made the tie itself a symbol of power and respect. And this led the tie to be adopted by a much larger tribe (群体) — the business tribe.
You cannot wear a tie if you work with machinery. So wearing a tie became a sign that you were a man who used his brain to make a living, rather than his hands. It showed you were serious. It showed you were a professional. It meant that everyone who wanted a job in business had to wear one. It was just impossible to take seriously a man who didn’t wear a piece of coloured silk around his neck. This is how millions of people came to be wearing ties across the world. They are part of the uniform of business.
“Ties offer a point of difference,” says John Milne, head of the British Guide of Tie Makers. “They give a chance to say something about their owner’s personality.”
So if you happen to meet a man with a very brightly coloured tie, there’s a good chance that he is the office joker. There’s also a good chance that he will be wearing brightly coloured socks.
Is there a future for ties? The signs are not promising. Tie wearing seems to be rare among the new breed of entrepreneurs(企业家) in the Internet and new technology industries. Many political leaders now go without ties. This shows they are men of the people — but not the people wearing ties.
Up until around 1960, it was common for men across the Western world to wear hats as part of their business uniform. That changed with the election of John F. Kennedy to the presidency of the United States. Kennedy never wore a hat — in fact his nickname was “hatless Jack”. Seeing that the most powerful man in the world did not have to wear a hat, millions of other men decided that they did not have to either. Hats simply vanished across the Western world. Perhaps “tieless Tony” will have the same effect on ties as “hatless Jack”.
1. In Britain, ties were first used as a sign to show a person’s ________.| A．personality | B．social position | C．wearing style | D．favourite hobby |
| A．it showed you used your brain | B．it showed you got a good salary |
| C．it showed you were an employer | D．it showed you were well-trained |
| A．Blair is the best leader in the world | B．Kennedy is the best leader in the world |
| C．more people will go to work without ties | D．people will wear hats instead of ties |
| A．disappeared | B．washed | C．expanded | D．sold |
【推荐3】Vitamins are meant to improve people’s immune system, and with the spread of SARS many Chinese are taking vitamins A, C and E every day.
But some US researchers say that vitamin supplements can’t correct a poor diet, and that multivitamins have not been shown to prevent any diseases. It is also easy for high doses of certain vitamins and minerals to actually increase the risk of disease.
Experts say that they are no longer concerned about vitamins deficiencies. Those are almost unheard of today, even with the population eating fewer fruits and vegetables. Instead, the concern is with the dangers of vitamin excess (过量).
Dr. Benjamin Caballero, a member of the Food and Nutrition Board at the US National Academy of Sciences, said that for some supplements, including vitamin A, the difference between the normal dose from a healthy diet and the recommended dose that could lead to disease like osteoporosis (bone disease) was not large. Popular multivitamins, he added, often contain what could be risky dose.
Similar questions are being raised about other vitamins and minerals, particularly iron and vitamins E and C.
Researchers say the questions involve multivitamins taken by healthy people, not specific vitamins or minerals taken by groups with special needs.
Some elderly people, for example, may lack B12 because they lose their ability to absorb it from foods.
People who spend little time outdoors may require vitamin D, which the skin makes when it is exposed to sunlight. Even when older people are in the sun, aging skin loses much of its ability to create the vitamins.
“If you eat junk food every day, vitamins are the least of your problems.” said Dr Caballero. “You can’t replace a healthy diet. People are looking for the magic bullet which doesn’t exist.”
1. From the second paragraph, we can find that _________.| A．parents should prevent their children from taking vitamins |
| B．doctors shouldn’t use any vitamins on their patients |
| C．vitamins only increase the risk of disease |
| D．vitamins should be taken with care |
| A．People usually have unhealthy diet. | B．People usually lead a hard life. |
| C．People seldom lack vitamins. | D．People seldom suffer from disease. |
| A．is dangerous for people to take | B．is very useful to bone disease |
| C．should be taken carefully | D．should be taken by a large amount |
| A．have junk food every day |
| B．have a healthy diet every day |
| C．try to find the magic vitamins |
| D．take some vitamins every day |
