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房地产信托资金

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社会福利制度

能源是支撑人类文明进步的物质基础，是现代社会发展不可或缺的基本条件。在中国实现现代化和全体人民共同富裕的进程中，能源始终是一个重大的战略问题。 20世纪70年代末实行改革开放以来，中国的能源事业取得了长足发展。目前，中国已成为世界上最大的能源生产国，形成了煤炭、电力、石油、天然气以及新能源和可再生能源全面发展的能源供应体系，能源普遍服务水平大幅提升，居民生活用能条件极大改善。能源的发展，为消除贫困、改善民生、保持经济长期平稳较快发展提供了有力保障。中国能源发展面临着诸多挑战。能源资源禀赋不高，煤炭、石油、天然气人均拥有量较低。能源消费总量近年来增长过快，保障能源供应压力增大。化石能源大规模开发利用，对生态环境造成一定程度的影响。

What is a black hole Well, it"s difficult to answer this question, since the terms we would normally use to describe a scientific phenomenon are inadequate here. Astronomers and scientists think that a black hole is a region of space (not a thing) into which matter has fallen and from which nothing can escape not even light. So we can"t see a black hole. A black hole exerts a strong gravitational pull and yet it has no matter. It is only space—or so we think. How can this happen The theory, is that some stars explode when their density increases to a particular point; they collapse and sometimes a supernova occurs. From Earth, a supernova looks like a very bright light in the sky which shines even in the daytime. The most convincing evidence of black holes comes from research into binary star systems. Binary stars, as their name suggests, are twin stars whose position in space affects each other. In some binary systems, astronomers have shown that there is an invisible companion star, a "partner" to the one which we can see in the sky. Matter from the one which we can see is being pulled towards the companion star. Could this invisible star, which exerts such a great force, be a black hole Astronomers have evidence of a few other stars too, which might have black holes as companions. The story of black holes is just beginning. Speculations about them are endless. There might be a massive black hole at the center of our galaxy swallowing up stars at a very rapid rate. Mankind may one day meet this fate. On the other hand, scientists have suggested that very advanced technology could one day make use of the energy of black holes for mankind. These speculations sound like science fiction. But the theory of black holes in space is accepted by many serious scientists and astronomers. They show us a world which operates in a totally different way from our own and they question our most basic experience of space and time. [Key words] supernova 超新星 galaxy 银河，星系

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