He shifted his position a little in order to (alleviate) the pain in his leg.[1分]
Our aim was to (update) the health service, and we succeeded.[1分]
She moves from one (exotic) location to another.[1分]
Nothing would (induce) me to vote for him again.[1分]
The photographs (evoked) strong memories of our holiday in France.[1分]
The weather was (crisp) and clear and you could see the mountains fifty miles away.[1分]
Every week the magazine presents the (profile) of a well-known sports personality.[1分]
Her comments about men are (utterly) ridiculous completely.[1分]
The walls are made of (hollow) concrete blocks.[1分]
We almost (ran into) a Rolls-Royce that pulled out in front of us without signaling.[1分]
When I heard the noise in the next room, I couldn’t resist having a (peep) look.[1分]
He has been granted (asylum) in France.[1分]
He was (weary) of the constant battle between them.[1分]
Newborn babies can (discriminate) between a man’s and a woman`s voice.[1分]
All the flats in the building had the same (layout) arrangement.[1分]
Europa’s Watery Underworld
Europa, one of Jupiter’s 63 known moons, looks bright and icy on the surface. But appearances can be deceiving: Miles within its cracked, frigid shell, Europa probably hides giant pools of liquid water. Where scientists find liquid water, they hope to find life as well.
Since we can’t go diving into Europa’s depths just yet, scientists instead have to investigate the moon’s surface for clues to what lies beneath. In a new study, scientists investigated one group of strange ice patterns on Europa and concluded that the formations mark the top of an underground pool that holds as much water as the U.S. Great Lakes.
Pictures of Europa, which is slightly smaller than Earth’s moon, clearly show a tangled(错综复杂的), icy mishmash(混合物) of lines and cracks known as “chaos terrains.(混乱地形)” These chaotic places cover more than half of Europa. For more than 10 years, scientists have wondered what causes the formations. The new study suggests that they arise from the mixing of vast underground stores of liquid water with icy material near the surface.
For scientists who suspect that Europa also may be hiding life beneath its icy surface, the news about the new lake is exciting.
“It would be great if these lakes harbored life,” Britney Schmidt, a planetary scientist who worked on the study, told Science News. “But even if they didn’t, they say that Europa is doing something interesting and active right now.”
Schmidt, a scientist at the University of Texas at Austin, and her colleagues wanted to know how chaos terrains form. Since they couldn’t rocket to Europa to see for themselves, they searched for similar formations here on Earth. They studied collapsed ice shelves in Antarctica and icy caps on volcanoes in Iceland. Those features on Earth formed when liquid water mixed with ice. The scientists now suspect something similar might be happening on Europa: that as water and ice of different temperatures mingle and shift, the surface fractures. This would explain the jumbled(混乱的)ice sculptures.
“Fracturing catastrophically(灾难性的)disrupts the ice in the same way that it causes ice shelves to collapse on Earth,” Schmidt told Science News. She and her team found that the process could be causing chaos terrains to form quickly on Europa.
The new study suggests that on this moon, elements such as oxygen from the surface blend with the deep bodies of water. That mixture may create an environment that supports life.
The liquid water of an underground pool of Europa is estimated xxxxx of the US Great lakes.[1分]
The strange ice patterns on Europa are formed as a result of a xxxxx underground water pool.[1分]
Europa is the most recently discovered one among Jupiter’s[1分]
The size of Europa is a bit larger than that of Earth’s moon.[1分]
Schmidt and her colleagues are the first group of scientists xxxxx Europa.[1分]
The formations on Europa’s surface are rather unique in the[1分]
The existence of liquid water is a necessity for a life-support[1分]
Learn about Noble Gases(惰性气体)
1.Have you ever ridden on a balloon? Many tourist spots offer balloon rides in order for people to see the beauty of a place from above. A balloon contains a noble gas called helium. Formerly, balloons contained hydrogen but hydrogen is very flammable and dangerous when uncontrolled. Therefore, people shifted to helium, which is safer. Helium is safe because it has the properties of the noble gases.
2.People once believed that noble gases couldn’t chemically react at all. For this reason, they were called inert gases. They were also clustered under Group 0 in the old periodic table because scientists believed that the gases have zero valence electrons in their outer shell. This was later proven to be untrue when some noble gas compounds were discovered.
3.The gases are elements, which share similar properties. These properties include being monoatomic, colorless, odorless, being able to conduct electricity, and having low chemical reactivity. Noble gases include Helium, Neon, Argon, Krypton, Xenon and Radon. These are all found in Group 18, in the rightmost column of the periodic table. If you look at the periodic table, you will notice that these elements are the only ones, which do not have a charge. Helium has the lowest molecular(分子的) weight while Radon is the heaviest.
4.Remember that chemical reactions occur because atoms have “valence” electrons, which are electrons in their outer shell. When the outer shell is “unfilled” or the required number of electrons is not yet complete, the atom is more reactive. Noble gases have a full outer shell, meaning that they have complete electrons in their outer shell. This complete number varies. For instance, the outer shell of Helium has 2 valence electrons while the outer shell of Xenon has 8 electrons. Nowadays, there remains to be a few noble gases because of the inherent low chemical reactivity of these said gases.
5.Because of their properties, noble gases have many important applications. They are widely used in recreation, medicine and industries. For instance, Liquid Helium is used for superconducting magnets(磁体). These magnets are very important in physics and medicine. When a doctor suspects that a person’s brain has been damaged, he might request for Magnetic Resonance Imaging (MRI). MRI allows the doctor to “see” the brain, without operating on the patient.
A.What are the applications of noble gases?
B.How were noble gases discovered?
C.What are noble gases?
D.What cause the low chemical reactivity of noble gases?
E.How were noble gases understood in the past?
F.What is the periodic table?
Noble gases are not very chemically______.[1分]
Among the elements of noble gases Helium is the____.[1分]
The required number of electrons in noble gases` outer shell is _____.[1分]
MRI may make operating on the patient ______.[1分]
Small But Wise
On December 14,NASA blasted a small but mighty telescope into space.The telescope is called WISE and is about as wide around as a trashcan.Don't let its small size fool you:WISE has a powerful digital camera,and it will be taking pictures of some the wildest objects in the known universe,including asteroids,faint stars,blazing galaxies and giant clouds of dust where planets and stars are born.
“I'm very excited because we're going to be seeing parts of the universe that we haven't seen before,” said Ned Wright,a scientist who directs the WISE project.
Since arriving in space,the WISE telescope has been circling the Earth,held by gravity in a polar orbit(this means it crosses close to the north and south poles with each lap).Its camera is pointed outward,away from the Earth,and WISE will snap a picture of a different part of the sky every 11 minutes.After six months it will have taken pictures across the entire sky.
The pictures taken by WISE won't be like everyday digital photographs,however.WISE stands for “Wide-field Infrared Survey Explorer.” As its name suggests,the WISE camera takes pictures of features that give off infrared radiation.
Radiation is energy that travels as a wave.Visible light,including the familiar spectrum of light that becomes visible in a rainbow,is an example of radiation.When an ordinary digital camera takes a picture of a tree,for example,it receives the waves of visible light that are reflected off the tree.When these waves enter the camera through the lens,they're processed by the camera,which then puts the image together.
Waves of infrared radiation are longer than waves of visible light,so ordinary digital cameras don't see them,and neither do the eyes of human beings.Although invisible to the eye,longer infrared radiation can be detected as warmth by the skin.
That's a key idea to why WISE will be able to see things other telescopes can't. Not everything in the universe shows up in visible light.Asteroids,for example,are giant rocks that float through space—but they absorb most of the light that reaches them.They don't reflect light,so they're difficult to see.But they do give off infrared radiation,so an infrared telescope like WISE will be able to produce images of them.During its mission WISE will take pictures of hundreds of thousands of asteroids.
Brown dwarfs are another kind of deep-space object that will show up in WISE's pictures.These objects are “failed” stars-which means they are not massive enough to jump start the same kind of reactions that power stars such as the sun.Instead,brown dwarfs simply shrink and cool down.They're so dim that they're almost impossible to see with visible light,but in the infrared spectrum they glow.
What is so special about WISE?[3分]
It is as small as a trashcan.
It is small in size but carries a large camera.
Never before has a telescope carried a digital camera in space.
Its digital camera can help astronomers to see the unknown space.
The camera on WISE[3分]
produces images of objects giving off infrared radiation.
is equipped with expensive computers
reflects light visible to the human eye
is similar to an ordinary digital camera
It is true that infrared radiation[3分]
is not detectable to human
looks bright than visible light
is visible light reflected off an object
has longer waves that those of visible light
Which of the following statements about asteroid is NOT true?[3分]
The WISE telescope can take pictures of asteroids.
They do not reflect light that reaches them.
They are invisible to ordinary camera.
They float through space giving off visible light.
It can be inferred from the last paragraph that brown dwarfs?[3分]
are power stars like the sun.
become massive and active.
are invisible to the WISE telescope.
Download Knowledge Directly to Your Brain
For the first time, researchers have been able to hack into the process of learning in the brain, using induced brain patterns to create a learned behavior. It’s not quite as advanced as an instant kung-fu download, and it’s not as sleek as cognitive inception, but it’s still an important finding that could lead to new teaching and rehabilitation techniques.
Future therapies could decode the brain activity patterns of an athlete or a musician, and use them as a benchmark for teaching another person a new activity, according to the researchers.
Scientists from Boston University and ATR Computational Neuroscience Laboratories in Kyoto used functional magnetic resonance imaging, or fMRI, to study the learning process. They were examining the adult brain’s aptitude for visual perceptual learning, or VPL, in which repetitive training improves a person’s performance on a particular task. Whether adults can do this as well as young people has been an ongoing debate in neuroscience.
Led by BU neuroscientist Takeo Watanabe, researchers used a method called decoded fMRI neurofeedback to stimulate the visual cortex. First they showed participants circles at different orientations. Then they used fMRI to watch the participants’ brain activity. The researchers were then able to train the participants to recreate this visual cortex activity.
The volunteers were again placed in MRI machines and asked to visualize shapes of certain colors. The participants were asked to “somehow regulate activity in the posterior part of the brain” to make a solid green disc as large as they could. They were told they would get a paid bonus proportional to the size of this disc, but they weren’t told anything about what the disc meant. The researchers watched the participants’ brain activity and monitored the activation patterns in their visual cortices.
“Participants can be trained to control the overall mean activation of an entire brain region,” the study authors write, “or the activation in one region relative to that in another region.”
This worked even when test subjects were not aware of what they were learning, the researchers said.
“The most surprising thing in this study is that mere inductions of neural activation patterns corresponding to a specific visual feature led to visual performance improvement on the visual feature, without presenting the feature or subjects' awareness of what was to be learned,” Watanabe said in a statement.
Watanabe and colleagues said this method can be a powerful tool.
“It can ‘incept’ a person to acquire new learning, skills, or memory, or possibly to restore skills or knowledge that has been damaged through accident, disease, or aging, without a person’s awareness of what is learned or memorized,” they write.
What have researchers been able to do with the help of the study?[3分]
make a person know how to do something without learning
set up different learning patterns for different people
Enable people to learn kung fu instantly
Discover a person’s learning process in the brain
What helps a person to do a particular task better in visual perceptual learning?[3分]
Which of the following statements is true of the experiment participants?[3分]
They were not told what to be learned in the experiment.
They learned how to control MRL machines in the experiment.
They were paid to take part in the experiment.
They were not cooperative in the experiment.
The finding of the study is most significant in that learning[3分]
Who are most likely to benefit from the stability?[3分]
Gross National Happiness
In the last century, new technology improved the lives of many people in many countries. However, one country resisted these changes. High in the Himalayan mountains of Asia, the kingdom of Bhutan remained separate. Its people and Buddhist(佛教)culture had not been affected for almost a thousand years. Bhutan, however, was a poor country. People died at a young age. Most of its people could not read, and they did not know much about the outside world. Then,in 1972,a new ruler named King Jigme Singye Wangchuck decided to help Bhutan to become modern,but without losing its traditions.
King Wangchuck looked at other countries for ideas. He saw that most countries measured their progress by their Gross Natonal Product(GNP)｡ The GNP measures products and money. When the number of products sold increases, people say the country is making progress. King Wangchuck had a different idea for Bhutan. He wanted to measure his country’s progress by people’s happiness. If the people’s happiness increased, the king could say that Bhutan was making progress. To decide if people were happier, he created a measure called Gross National Happiness(GNH)｡ GNH is based on certain principles that create happiness. People are happier if they have health care, education, and jobs. They are happier when they live in a healthy, protected environment. They are happier when they can keep their traditional culture and customs. Finally, people are happier when they have a good, stable government. Now these is some evidence of increased GNH in Bhutan. People are healthier and are living longer. More people are educated and employed. Twenty-five percent of the land has become national parks, and the country has almost no pollution. The Bhutanese continue to wear their traditional clothing and follow their ancient Buddhist customs. Bhutan has also become a democracy. In 2008,King Wangchuck gave his power to his son. Although the country still had a king, it held its first democratic elections that year. Bhutan had political parties and political candidates for the first time. Finally, Bhutan has connected to the rest of the world through television and internet. Bhutan is a symbol for social progress. Many countries are now interested in Bhutan’s GNH. These countries are investigating their own ways to measure happiness. They want to create new policies that take care of their people,cultures,and land. Brazil may be the nest country to use the principles of GNH. Brazilian leaders see the principles of GNH as a source of inspiration. Brazil is a large country with a diverse population. If happiness works as a measure of progress in Brazil, perhaps the rest of the world will follow.
Who was Jigme Singye Wangchuck?[3分]
Apart from modernizing Bhutan, what else did Wangchuck want to do for Bhutan?[3分]
To make its population grow.
To keep it separate from the world.
To encourage its people to get rich.
To keep its tradition and customs.
A country shows its progress with GNP by[3分]
According to GNH, people are happier if they[3分]
can change their religion.
have a good, stable government.
Today, many countries are[3分]
using the principles of GNH to measure their progress.
working together to develop a common scale to measure GNH.
taking both Bhutan and Brazil as symbols for social progress.
trying to find their own ways to measure happiness.
The Mysteries of Nazca
In the desert of Peru, 300 kilometers from Lima, one of the most unusual artworks in the world has mystified (迷惑) people for decades.
(46) But from high above, these marks are huge images of birds, fish, seashells, all beautifully carved into the earth.
The Nazca lines are so difficult to see from the ground that they weren’t discovered until the 1930s, when pilots spotted them while flying over the area. In all, there are about 70 different human and animal figures on the plain, along with 900 triangles, circles, and lines.
Researchers have figured out that the lines are at least 1,500 years old, but their purpose is still a mystery.
(47) However, it would probably be very tricky to xxxxx(单词暂不明) and a spaceship in the middle of pictures of dogs and monkeys.
In the 1940s, an American explorer named Paul Kosok suggested that the drawings are a chronicle (记录) of the movement of the stars and planets.
(48) xxxxx an astronomer tested his theory with a computer, but he couldn’t find any relation between the lines and movements in space.
Another explanation is that the lines may have been made for religious reasons. xxxxx researcher Tony Morrison investigated the customs of people in the Andes xxxxx and learned that they sometimes pray by the side of the road. It’s possible that xxxxx, the lines of Nazca were created for a similar purpose.
(49) But xxxxx people have never constructed anything this big.
Recently, two other scientists, David Johnson and Steve Mabee, have speculated xxxxx lines could have been related to water. Nazca is one of the driest places in the xxxxx receives only 2cm of rain every year. While Johnson was searching for xxxxx water sources in the area, he noticed that some waterways built ancient xxxxx were connected with the lines. Johnson believes that the Nazca lines are a giant xxxxx underground water in the area.
A.Other scientists are now searching for evidence to prove this.
B.A Swiss writer named Erich Von Daniken wrote that the Nazca lines were designed as a landing place for UFOs.
C.Scholars differ in interpreting the purpose of the designs.
D.The largest pictures may have been the sites for special ceremonies.
E.Seen from the ground, it looks like lines scratched into the earth.
F.He called Nazca “the largest astronomy book in the world”.
Solar Power without Solar Cells
A dramatic and surprising magnetic effect of light discovered by University of Michigan researchers could lead to solar power without traditional semiconductor-based solar cells.
The researchers found a way to make an "optical ______(51)," said Stephen Rand, a professor in the departments of Electrical Engineering and Computer Science, Physics and Applied Physics.
Light has electric and magnetic ______(52). Until now, scientists thought the effects of the magnetic field were so weak that they could be ______ (53). What Rand and his colleagues found is that at the right intensity, when light is traveling through a material that does not ______ (54) electricity, the light field can generate magnetic effects that are 100 million times stronger than previously expected. Under these circumstances, the magnetic effects develop strength ______ (55) to a strong electric effect.
"This could lead to a new kind of solar cell without semiconductors and without absorption to produce charge separation," Rand said. "In solar cells, the ______ (56) goes into a material, gets absorbed and creates heat. Here, we expect to have a very low heat load. Instead of the light being absorbed, energy is stored in the magnetic moment. Intense magnetization can be induced by intense light and then it is ultimately capable of providing a capacitive power ______ (57)." What makes this possible is a previously undetected brand of "optical rectification," says William Fisher, a doctoral student in applied physics. In traditional optical rectification, light's electric field causes a charge separation, or a pulling ______ (58) of the positive and negative charges in a material. This sets up a voltage, similar to ______ (59) in a battery.
Rand and Fisher found that under the right circumstances and in right types of materials, the light's magnetic field can also create optical rectification. The light must be shone through a ______ (60) that does not conduct electricity, such as glass. And it must be focused to an intensity of 10 million watts per square centimeter. Sunlight isn't this ______ (61) on its own, but new materials are being sought that would work at lower intensities, Fisher said.
"In our most recent paper, we show that incoherent light like sunlight is theoretically almost ______ (62) effective in producing charge separation as laser light is,” Fisher said.
This new technique(换成了technology) (63) could make solar power cheaper, the researchers say. They predict that with improved materials they could achieve 10 percent efficiency in converting (63) solar power to useable energy. That's equivalent to today's commercial-grade solar cells.
"To manufacture modern solar cells, you have to do ______ (64) semiconductor processing," Fisher said. "All we would need are lenses to focus the light and a fiber to guide it. Glass works for ______ (65). It's already made in bulk, and it doesn't require as much processing. Transparent ceramics might be even better."