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单选题An experiment that some hoped would reveal a new class of subatomic particles, and perhaps even point to clues about why the universe exists at all, has instead produced a first round of results that are mysteriously inconclusive. Dr. Conrad and William C. Louis presented their initial findings in a talk yesterday at the Fermi National Accelerator Laboratory where the experiment is being performed. The goal was to confirm or refute observations made in the 1990s in a Los Alamos experiment that observed transformations in the evanescent but bountiful particles known as neutrinos(微中子). Neutrinos have no electrical charge and almost no mass, but there are so many of them that they could collectively outweigh all the stars in the universe. The new experiment has attracted wide interest. That reflected in part the hope of finding cracks in the Standard Model, which encapsulates physicists' current knowledge about fundamental particles and forces. The Standard Model has proved remarkably effective and accurate, but it cannot answer some fundamental questions, like why the universe did not completely annihilate(毁灭) itself an instant after the Big Bang. The birth of the universe 13.7 billion years ago created equal amounts of matter and antimatter. Since matter and antimatter annihilate each other when they come in contact, that would have left nothing to coalesce into stars and galaxies. There must be some imbalance in the laws of physics that led to a slight preponderance of matter over antimatter, and that extra bit of matter formed everything in the visible universe. The imbalance, some physicists believe, may be hiding in the dynamics of neutrinos. Neutrinos come in three known types, or flavors. And they can change flavor as they travel. But the neutrino transformations reported in the Los Alamos data do not fit the three-flavor model, suggesting four flavors of neutrinos, if not more. The new experiment sought to count the number of times one flavor of neutrino, called a muon(μ介子), turned into another flavor, an electron neutrino. For most of the neutrino energy range they looked at, the scientists did not see any more electron neutrinos than would be predicted by the Standard Model. That ruled out the simplest ways of interpreting the Los Alamos neutrino data, Dr. Conrad and Dr. Louis said. But at the lower energies, the scientists did see more electron neutrinos than predicted: 369, rather than the predicted 273. That may simply mean that some calculations are off. Or it could point to a subtler interplay of particles, known and unknown. Dr. Louis said he was surprised by the results." I was sort of expecting a clear excess or no excess," he said. "In a sense, we got both./
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单选题According to the passage, scientists failed to______
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单选题Do you remember all those years when scientists argued that smoking would kill us but the doubters insisted that we didn"t know for sure? That the evidence was inconclusive, the science uncertain? That the antismoking lobby was out to destroy our way of life and the government should stay out of the way? Lots of Americans bought that nonsense, and over three decades, some 10 million smokers went to early graves. There are upsetting parallels today, as scientists in one wave after another try to awaken us to the growing threat of global warming. The latest was a panel from the National Academy of Sciences, enlisted by the White House, to tell us that the Earth"s atmosphere is definitely warming and that the problem is largely man-made. The clear message is that we should get moving to protect ourselves. The president of the National Academy, Bruce Alberts, added this key point in the preface to the panel"s report: "Science never has all the answers. But science does provide us with the best available guide to the future, and it is critical that our nation and the world base important policies on the best judgments that science can provide concerning the future consequences of present actions." Just as on smoking, voices now come from many quarters insisting that the science about global warming is incomplete, that it"s OK to keep pouring fumes into the air until we know for sure. This is a dangerous game: by the time 100 percent of the evidence is in, it may be too late. With the risks obvious and growing, a prudent people would take out an insurance policy now. Fortunately, the White House is starting to pay attention. But it"s obvious that a majority of the president"s advisers still don"t take global warming seriously. Instead of a plan of action, they continue to press for more research—a classic case of " paralysis by analysis ". To serve as responsible stewards of the planet, we must press forward on deeper atmospheric and oceanic research. But research alone is inadequate. If the Administration won"t take the legislative initiative, Congress should help to begin fashioning conservation measures. A bill by Democratic Senator Robert Byrd of West Virginia, which would offer financial incentives for private industry, is a promising start. Many see that the country is getting ready to build lots of new power plants to meet our energy needs. If we are ever going to protect the atmosphere, it is crucial that those new plants be environmentally sound.
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单选题Material culture refers to the touchable, material "things" --physical objects that can be seen, held, felt, used--that a culture produces. Examining a culture's tools and technology can tell us about the group's history and way of life Similarly, research into the material culture of music can help us to understand the music culture. The most vivid body of "thing" in it, of course, is musical instruments. We cannot hear for ourselves the actual sound of any musical, performance before the 1870s when the phonograph was invented, so we rely on instruments for important information about music-cultures in the remote past and their development. Here we have two kinds of evidence: instruments well preserved and instruments pictured in art. Through the study of instruments, as well as paintings, written documents, and so on, we can explore the movement of music from the Near East to China over a thousand years ago, for we can outline the spread of Near Eastern influence to Europe that resulted in the development of most of the instruments on the symphony orchestra. Sheet music or printed music, too, is material culture. Scholars once defined folk music-cultures as those in which people learn and sing music by ear rather than from print, but research shows mutual influence among oral and written sources during the past few centuries in Europe, Britain and America. Printed versions limit variety because they tend to standardize any song, yet they stimulate people to create new and different songs. Besides, the ability to read music notation has a far-reaching effect on musicians and, when it becomes widespread, on the music-culture as a whole. Music is deep-rooted in the cultural background that fosters it. We now pay more and more attention to traditional or ethnic features in folk music and are willing to preserve the fold music as we do with many traditional cultural heritage. Musicians all over the world are busy with recording classic music in their country for the sake of their unique culture. As always, people's aspiration will always focus on their individuality rather than universal features that are shared by all cultures alike. One more important part of music's material culture should be singled out: the influence of the electronic media--radio, record player, tape recorder, and television, with the future promising talking and singing computers and other developments. This is all part of the "information-revolution", a twentieth-century phenomenon as important as the industrial revolution in the nineteenth. These electronic media are not just limited to modern nations; they have affected music cultures all over the globe.
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单选题{{B}}Text 1{{/B}} All that we really need to plot out the future of our universe are a few good measurements. This does not mean that we can sit down today and outline the future course of the universe with anything like certainty. There are still too many things we do not know about the way the universe is put together. But we do know exactly what information we need to fill in our knowledge, and we have a pretty good idea of how to go about getting it. Perhaps the best way to think of our present situation is to imagine a train coming into a switchyard. All of the switches are set before the train arrives, so that its path is completely determined. Some switches we can see, others we cannot. There is no ambiguity if we can see the setting of a switch: we can say with confidence that some possible futures will not materialize and others will. At the unseen switches, however, there is no such certainty. We know the train will take one of the tracks leading out, but we have no idea which one. The unseen switches are the true decision points in the future, and what happens when we arrive at them determines the entire subsequent course of events. When we think about the future of the universe, we can see our "track" many billions of years into the future, but after that there are decision points to be dealt with and possible fates to consider. The goal of science is to reduce the ambiguity at the decision points and find the true road that will be followed.
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单选题According to the author, the "Space Race" was______.
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单选题Du Bois was a sociological and educational pioneer who challenged the established system of education that tended to restrict rather than to advance the progress of black Americans. He challenged what is called the “Tuskegee machine” of Booker T. Washington, the leading educational spokesperson of the blacks in the U. S. . As a sociologist and historian, Du Bois called for a more determined and activist leadership than Washington provided. Unlike Washington, whose roots were in southern black agriculture, Du Bois’s career spanned both sides of the Mason-Dixon Line. He was a native of Massachusetts, received his undergraduate education from Fisk University in Nashville, did his graduate study at Harvard University, and directed the Atlanta University Studies of Black American Life in the South. Du Bois approached the problem of racial relations in the United States from two dimensions: as a scholarly researcher and as an activist for civil rights. Among his works was the famous empirical sociological study, The Philadelphia Negro: A Social Study, in which he examined that city’s black population and made recommendations for the school system. Du Bois’s Philadelphia study was the pioneer work on urban blacks in America. Du Bois had a long and active career as a leader in the civil rights movement. He helped to organize the Niagara Movement in 1905, which led to the National Association for the Advancement of Colored People (NAACP), established in 1909. From 1910 until 1934, Du Bois edited The Crisis, the major journal of the NAACP. In terms of its educational policy, the NAACP position was that all American children and youth should have genuine equality of educational opportunity. This policy, which Du Bois helped to formulate, stressed the following themes: (1) public schooling should be free and compulsory for all American children; (2) secondary schooling should be provided for all youth; (3) higher education should not be monopolized by any special class or race. As a leader in education, Du Bois challenged not only the tradition of racial segregation in the schools but also the accommodationist ideology of Booker T. Washington. The major difference between the two men was that Washington sought change that was evolutionary in nature and did not upset the social order, whereas Du Bois demanded immediate change. Du Bois believed in educated leadership for blacks, and he developed a concept referred to as the “talented tenth”, according to which 10 percent of the black population would receive a traditional college education in preparation for leadership.
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单选题{{B}}Text 1{{/B}} People in business can use foresight to identify new products and services, as well as markets for those products and services. An increase in minority populations in a neighborhood would prompt a grocer with foresight to stock more foods linked to ethnic tastes. An art museum director with foresight might follow trends in computer graphics to make exhibits more appealing to younger visitors. Foresight may reveal potential threats that we can prepare to deal with before they become crises. For instance, a corporate manager with foresight might see an alarming rise in local housing prices that could affect the availability of skilled workers in the region. The public's changing values and priorities, as well as emerging technologies, demographic shifts, economic constraints (or opportunities), and environmental and resource concerns are all parts of the increasingly complex world system in which leaders must lead. People in government also need foresight to keep systems running smoothly, to plan budgets, and to prevent wars. Government leaders today must deal with a host of new problems emerging from rapid advances in technology. Even at the community level, foresight is critical: School officials, for example, need foresight to assess numbers of students to accommodate, numbers of teachers to hire, new educational technologies to deploy, and new skills for students (and their teachers) to develop. Many of the best-known techniques for foresight were developed by government planners, especially in the military, when the post-World War II atomic age made it critical to "think about the unthinkable" and prepare for it. Pioneering futurists at the RAND Corporation (the first "think tank ") began seriously considering what new technologies might emerge in the future and how these might affect U. S. security. These pioneering futurists at RAND, along with others elsewhere, refined a variety of new ways for thinking about the future. The futurists recognized that the future world is continuous with the present world, so we can learn a great deal about what may happen in the future by looking systematically at what is happening now. The key thing to watch is not events ( sudden developments or one-day occurrences) but trends (long-term ongoing shifts in such things as population, land use, technology, and governmental systems) . Using these techniques and many others, futurists now can tell us many things that may happen in the future. Some are nearly certain to happen, such as the continuing expansion in the world's population. Other events are viewed as far less likely, but could be extremely important if they do occur, such as an asteroid colliding with the planet.
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单选题In the eighties, the Americans as a whole ______.
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单选题{{B}}Text 2{{/B}} As any diplomat from Britain, Austria or Turkey can tell you, handling the legacy of a vanished, far-flung empire is a tricky business. But for Georgia, the gap between old glory and present vulnerability is especially wide. Today's Georgia is diminished by war, buffeted by geopolitics and recovering from post-Soviet chaos. But 800 years ago the country was a mighty military, cultural and ecclesiastical force. Its greatest monarch, Queen Tamara, defeated many foes (including her first husband) and built fine monuments. In her time, Georgia also had a big stake in the Christian life of the Holy Land. From Jerusalem to the Balkans, Georgia's priests, artists and church-builders were active and respected. So too were its poets, like Shota Rustaveli, the national bard who dedicated an epic to his beloved queen. In between seeking western aid and coping with power cuts, modern Georgia has pledged to keep a wary eye on every place where churches, inscriptions and frescoes testify to its golden age. That includes Greece, Turkey, Bulgaria, Romania and above all, Israel. Last year, Georgians were enraged when a fresco of Rustaveli, in a Jerusalem church under the care of the Greek Orthodox Patriarchate, was defaced, then badly restored. This year, a better restoration was done, but Georgians now want a promise that in all future restoration their own experts can take part. They also want to stop the seepage of Georgian frescoes and icons, supposedly under the Patriarchate's care, on to the art market. Several times, Georgia has had to use its meagre resources to buy back pieces of the national heritage. The hope is that things will improve with the recent election of a new Jerusalem Patriarch, after his predecessor was ousted under a cloud of scandal. Georgia's ties with Israel are good, thanks to a thriving Georgian-Jewish community with happy memories of its homeland. Georgia also gets along with Greece, amid a fug of sentimentality over legends about the Argonauts that link the two nations. But can these warm, fuzzy feelings translate into better protection for an ancient culture? That will be a challenge for Geld Bezhuashvili, who succeeds Salome Zourabichvili, the French-born diplomat who was sacked, after a power struggle, as Georgian foreign minister on October 19th.
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单选题 The earliest evidence of standardized testing based on merit comes from China during the Han dynasty. The concept of a state ruled by men of ability and virtue was an outgrowth of Confucian philosophy. Standardized testing has not traditionally been a part of European pedagogy. Based on the skeptical and open-ended tradition of debate inherited from Ancient Greece, Western academia favored the essay. The use of standardized testing in the United States is a 20th century phenomenon with its origins in World War I. One of the main advantages of standardized testing is that the results can be empirically documented ; therefore the test scores can be shown to have a relative degree of validity and reliability, as well as results which are generalizable and replicable. This is often contrasted with grades on a school transcript, which are assigned by individual teachers. Another advantage is aggregation. A well designed standardized test provides an assessment of an individual's mastery of a domain of knowledge or skill which at some level of aggregation will provide useful information. Though many educators recognize that standardized tests have a place in tools used to assess student achievement, critics feel that overuse and misuse of these tests is having serious negative consequences on teaching and learning. The temptation is to use the tests to define curriculum and focus instruction. What is not tested is not taught, and how the subject is tested becomes a model for how to teach the subject. Moreover, standardized test scores are problematic tools for school accountability because the examinee scores are influenced by three things: what kids learn in school, what kids learn outside of school, and innate intelligence. Critics believe this is not possible. While it is possible to use a standardized test and not let its limits control curriculum and instruction, this can result in a school putting itself at risk for producing lower test scores, with negative political consequences. Some critics say that some children do not do well on standardized tests, despite mastery of the material, due to testing anxiety or lack of time management or test-taking skills. This reflects the fact that tests cannot directly measure student knowledge, only the ability of students to apply knowledge in a stressful situation. Some parents are willing to pay thousands of dollars to prepare their children for tests, a financial barrier that may give children of more wealthy parents an advantage compared to less affluent families. However this criticism would probably apply even more to testing alternatives such as portfolios or essays. Many studies also show that test coaching has little effect on scores on well-buih tests. The ability of wealthy families to pay for higher-quality education is not specifically related to standardized testing.
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