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深圳光明新区人民医院脱毛多少钱深圳康宁医院做去眼袋手术多少钱深圳做双眼皮 Science and technology科学技术Solar power from space太空太阳能Beam it down, Scotty老兄,传下来吧Harvesting solar power in space, for use on Earth, comes a step closer to reality在太空获取太阳能以供地球之用:梦想距现实又近了一步THE idea of collecting solar energy in space and beaming it to Earth has been around for at least 70 years.在太空获取太阳能并传送回地球这一创意存在了至少有70年了。In “Reason”, a short story by Isaac Asimov that was published in 1941, a space station transmits energy collected from the sun to various planets using microwave beams.由艾萨克·阿西莫夫创作、1941年发表的短篇故事《推理》,描述了一个太空站将获取的太阳能以微波束的方式传送至多个星球的场景。The advantage of intercepting sunlight in space, instead of letting it find its own way through the atmosphere, is that so much gets absorbed by the air.相比于让阳光穿过大气层后再获取太阳能,在太空中截取太阳能的一大优点就是大气吸收的能量很少。By converting it to the right frequency first a space-based collector could, enthusiasts claim, yield on average five times as much power as one located on the ground.热衷者声称,首先通过调节阳光至适当频率,在太空中的太阳能收集器可以吸收五倍于地面收集器的能源。The disadvantage is cost.缺点在于成本高。Launching and maintaining suitable satellites would be ludicrously expensive.适用卫星的发射和维护成本会高得惊人。But perhaps not, if the satellites were small and the customers specialised.但也许不会—如果卫星足够小、且是为专门客户务。Military expeditions, rescuers in disaster zones, remote desalination plants and scientific-research bases might be willing to pay for such power from the sky.军事远征队、灾区救援人员、偏远的脱盐工厂和科研基地也许会愿意为太空太阳能买单。And a research group based at the University of Surrey, in England, hopes that in a few years it will be possible to offer it to them.英国萨里大学的一个研究小组希望在未来几年内可以提供太空太阳能。Heavenly power天国能源This summer, Stephen Sweeney and his colleagues will test a laser that would do the job which Asimov assigned to microwaves.今年夏天,斯蒂芬·斯维尼和同事将测试一个激光器,该激光器用来完成阿西莫夫为微波“指派”的任务。Certainly, microwaves would work: a test carried out in 2008 transmitted useful amounts of microwave energy between two Hawaiian islands 148km apart, so penetrating the 100km of the atmosphere would be a doddle.当然,微波可以发挥作用:2008年进行的一项测试为相距148公里的夏威夷两岛传送了大量的微波能,所以穿越100公里的大气层应该易如反掌。But microwaves sp out as they propagate.但微波在传送过程中会扩散。A collector on Earth that was picking up power from a geostationary satellite orbiting at an altitude of 35,800km would need to be sp over hundreds of square metres.接收35,800公里外的地球同步卫星传送的能源所需的地面收集器需覆盖数百平方米。Using a laser means the collector need be only tens of square metres in area.而使用激光器则意味着收集器面积仅需达到几十平米。Dr Sweeneys team, working in collaboration with Astrium,斯维尼士的团队正与卫星和太空公司Astrium合作。a satellite-and-space company that is part of EADS, a European aerospace group, will test the system in a large aircraft hangar in Germany.Astrium隶属于欧洲一航天集团欧洲宇航防务集团。斯维尼士的团队将在德国一座大型飞机库测试该系统。The beam itself will be produced by a device called a fibre laser.光束将由光纤激光器发出。This generates the coherent light of a laser beam in the core of a long, thin optical fibre.该激光器利用细长的光纤核心汇聚激光束。That means the beam produced is of higher quality than other lasers, is extremely straight and can thus be focused onto a small area.这意味着产生的光束比其他激光器发射的光束质量更高,最直接,也因此可以汇聚到更小的区域内。Another bonus is that such lasers are becoming more efficient and ever more powerful.另外一个益处就是此类激光器效率正逐步提高、力量更大。In the case of Dr Sweeneys fibre laser, the beam will have a wavelength of 1.5 microns, making it part of the infra-red spectrum. This wavelength corresponds to one of the best windows in the atmosphere.斯维尼士采用的光纤激光器发射的光束波长将达到1.5微米,从而使其达到红外线的光谱范围。该波长正处于大气最佳窗口之一。The beam will be aimed at a collector on the other side of the hangar, rather than several kilometres away.光束将瞄准飞机库另一侧的—而不是数公里之外的——收集器。The idea is to test the effects on the atmospheric window of various pollutants, and also of water vapour, by releasing them into the building.通过释放各种污染物以及水蒸气至机库中,该创意旨在测试这些物质对大气窗口的影响。Assuming all goes well, the next step will be to test the system in space.如果一切都进行顺利,下一步将是在太空中测试该系统。That could happen about five years from now, perhaps using a laser on the International Space Station to transmit solar power collected by its panels to Earth.这可能要在五年之后实现,或许会利用国际空间站上的激光器将空间站电池板收集的太阳能传送回地球。Such an experimental system would deliver but a kilowatt of power, as a test.作为测试,该试验系统将只传送一千瓦的能量。In 10-15 years Astrium hopes it will be possible to deploy a complete, small-scale orbiting power station producing significantly more than that from its own solar cells.Astrium 希望在未来10到15年的时间内能够建立一个完整的、小规模的、沿轨道运行的太阳能站,利用自身的太阳能电池发出大量电能。Other researchers, in America and Japan, are also looking at using lasers rather than microwaves to transmit power through the atmosphere.美日其他研究者也在考虑弃微波、用激光器,穿过大气层将能量传送回地球。NASA, Americas space agency, has started using them to beam energy to remotely controlled drones.美国航天机构国家航空航天局已开始采用激光器传送能源至遥控飞机。Each stage of converting and transmitting power results in a loss of efficiency, but with technological improvements these losses are being reduced.能量转化、传送的每一个环节都会有一定的功耗,但随着技术的改进,损耗正在降低。Some of the latest solar cells, for instance, can covert sunlight into electricity with an efficiency of more than 40%. In the 1980s, 20% was thought good.例如,部分最新型的太阳能电池将阳光转换成电能的功率超过了40%。而在上世纪80年代,20%的功率就很高了。Whether the Astrium system will remain a specialised novelty or will be the forerunner of something more like the cosmic power stations of Asimovs imagination is anybodys guess.Astrium 系统将是一个专业用途的创新,还是某个更接近阿西莫夫想象中的太空太阳能电站的先导?一切都还是未知数。But if it comes to pass at all, it will be an intriguing example, like the geostationary communications satellites dreamed up by Asimovs contemporary, Arthur C. Clarke, of the musings of a science-fiction author becoming science fact.但倘若系统通过测试,它定将激起人们的兴趣,正如与阿西莫夫同一时代的科幻小说作家亚瑟·C·克拉克所梦想的地球同步通讯卫星一样——梦想最终成为了现实。 /201304/236714German politics德国政治The Alternatives astonishing ascent新选项党的崛起As the large centrist parties become more alike, the radical fringe gets stronger大部分中立派议员趋同,激进派边缘增强SINCE reunification in 1990, Saxony has been the former East Germanys biggest success story. As one of Germanys 16 federal states since then, it has been governed continuously by the centre-right Christian Democrats (CDU). Its education system is considered Germanys best. Its economy is thriving, with world-class regional clusters in high-tech and carmaking. So there was never any question that Stanislaw Tillich, the states understated and popular CDU premier, would stay in power after Saxonys election on August 31st. His party won more votes than the three leftist parties combined. With 39.4% of votes, Mr Tillich claimed victory.自从1990年德国重新统一以后,萨克森州已经变成了前东德地区最成功的故事。自那时开始,作为联邦十六州之一的萨克森一直处在中右派的基督民主党统治之下。它的教育制度被认为是德国最好的,高科技与汽车制造业的地域集聚也使得它的经济情况日趋繁荣。毋庸置疑,低调行事且广受赞誉的基民党州长斯塔尼斯拉夫·提里希将在8月31日的大选后继续执政。基民党获得了超过三个左翼政党联盟的持率,34.9%的得票率宣告了提里希的胜利。And yet that result was the CDUs worst ever in Saxony, causing worries as the party approaches elections on September 14th in Thuringia and Brandenburg, also in former East Germany. The left-leaning Social Democrats (SPD) and ecology-minded Greens have reason to fret, too. They all did worse than they had hoped, largely because they lost votes to a populist party to the right of the CDU: the Alternative for Germany, led by Frauke Petry.但这是基民党在萨克森选举历史上最糟糕的结果,导致了他们对同样归属前东德地区的图林根州与勃兰登堡在9月14日政党换届大选的担忧。而左翼党派德国社会民主党与生态主义绿党也有同样的烦恼。他们比预期中做的更糟,很大程度上因为他们票选输给了一个比基民党作风更为保守的民粹新政党—由弗劳克·佩特里领导的新选项党。Founded last year, the Alternative began with only one policy: a call for the orderly unravelling of the euro as a currency zone. To this it has since added other conservative positions, such as opposition to public deficits and gay marriage. In some ways it resembles Americas Tea Party. In Saxony, where it is strongest, it has increasingly emphasised tougher controls on immigration and border crime, often with xenophobic innuendo.去年开始,新选项党遵循的唯一政策:呼吁有序解散欧元经济区。为此,党内开始增加其他保守立场,例如反对财政赤字与同性婚姻。在某种程度上它类似美国的茶党。在新选项党势力最强的萨克森州,它加强了对外来移民与边境犯罪的严格管控,并经常伴有排外情绪。Though still chaotic in its party organisation and evolving in its views—for example, the party is squabbling over whether to criticise Vladimir Putin or coddle him—the Alternative has been rising stunningly fast. It came close to entering the federal parliament last September and succeeded in entering the European one in May. With 9.7% of the vote in Saxony, it now enters its first state parliament. It hopes to do so in Thuringia and Brandenburg, too.即使政党内部观点开展的混乱不堪——比如为了要批评还是要优待普京而争吵——新选项党的依然在迅速成长。在去年九月它尝试进入联邦议院,并在五月份成功进入欧盟接替了一个席位。凭借在萨克森州9.7%的持率,它首次进入州议院并希望在图林根州与勃兰登堡市也能取得同样的结果。The new partys success is causing upheaval in the German political landscape, accelerating the implosion of its only liberal party, the Free Democrats (FDP). With just 3.8% of votes in Saxony, the FDP failed to clear the 5% threshold to enter parliament and was ejected, as it has been from seven other state parliaments since 2011 and the Bundestag last year. For the first time since 1946, the FDP does not participate in any state or federal government. This eliminates the liberals as the CDUs coalition partner, perhaps permanently.新政党的成功引起了德国政坛格局的转变,也加速了德国唯一一个自由党派—自由民主党的分裂。自2011年起它已经相继被其他7个州议院与去年的联邦议会大选“除名”,而今年萨克森选举中,3.8%的得票率让自民党又一次在议院5%持率的门槛前止步。这也是自1946年以来自民党首次未能进入任何州立或联邦政府,这种情况对于基民党的盟友—自民党的消除也许是永久性的。A more positive side-effect of the Alternatives ascent is its cannibalisation of the NPD, a neo-Nazi party.About 13,000 of its voters migrated to the Alternative, causing the NPD to fall 809 votes short of re-entering the Saxon parliament. After that loss, it has seats in only one other state and could fade away, with or without a ban.新选项党的成长带来的积极作用是与民粹政党—德国国家民主党的同类相残。约有1.3万名该党的持者转向了新选项党,缺少809个持票也直接导致了民主党无法重回议会。失败以后,无论同类相残是否被禁止,它在另一个州保留的仅有席位也可能消失。The CDU so far refuses to contemplate a coalition with the Alternative. Led nationally by the chancellor, Angela Merkel, the CDU is pro-European and pro-euro, and so moderate as to be increasingly indistinguishable to many voters from the SPD, with which it governs in a “grand coalition” in the Bundestag. On September 1st Mrs Merkel, Mr Tillich and the CDU leaders in Thuringia and Brandenburg said again that discussions with the Alternative are taboo. Mr Tillich will try to form a coalition with the SPD or the Greens.基民党至今拒绝考虑与新选项党联盟。在德国总理默克尔领导下的基民党是亲欧盟亲欧元的,如此温和的作风让人们越来越难以区分基民党与社民党,同时基民党还在西德联邦议会中掌管着大联盟。9月1日,默克尔、提里希和基民党其他领导人在图林根州与勃兰登堡市再一次表示,与新选项党讨论是被禁止的。提里希将会尝试与社民党或绿党建立联盟。Ignoring the Alternative will not remove it as a problem for the CDU. In effect, the Alternative has in one year become on the far right what The Left is on the left. Descended from East Germanys Communist Party and unreconciled to Germanys capitalist system and its Western alliances, The Left remains strong in the eastern states. In Saxony it came in second with 18.9% of the vote. The comparatively moderate SPD has so far ruled out The Left as a partner in the Bundestag. But their competition splits the left vote and often leads to unproductive ideological bidding wars.基民党的联盟问题不会因为忽视新选项党而解决。事实上,新选项党已经在一年以内成为了极右派,如同左派党是左翼倾向。起源于东德共产党的新选项党,虽然没有与德国资本主义系统以及西部联盟达成一致,但在东部各州实力依然强大。它在萨克森州公投中以18.9%的持率位居第二。相对温和的社民党已经排除了基民党在西联邦议院的左党伙伴。但是他们的竞争使得左派选票分裂,并且经常带来无意义的竞投战。The Alternative will increasingly play the same role on the right vis-a-vis the CDU. On September 1st, Mrs Merkel suggested that, short of negotiating with the Alternative, the CDU must begin dealing with the concerns, rational or not, of its supporters. These range from fears about crime in the regions along the borders with the Czech Republic and Poland, to hysteria about “welfare tourism” by foreigners. The Alternative will be at its shrillest and strongest every time the euro crisis returns to the headlines. This will restrict Mrs Merkels leeway to agree to new rescue packages, or even to ease her austerity drive.新选项党将逐渐与基民党扮演同样重要的角色。九月一日,默克尔建议,由于缺少与新选项党磋商,基民党必须开始解决来自它的持者们关心的问题,无论问题合理与否。持者们关心的范围从对捷克和波兰接壤的边境地区犯罪的担忧,到对外国人“公益旅行”的歇斯底里。新选项党在欧元危机重回一线的每时每刻都表现出尖利强硬的一面。这将限制默克尔的回旋余地,被迫同意新计划,甚至缓和她的紧缩计划 /201409/327426华中科技大学协和深圳医院去眼袋多少钱

深圳中心人民医院割双眼皮手术多少钱深圳全身吸脂减肥医院 光明新区腋窝脱毛多少钱

深圳市伊斯佑医院切眼袋多少钱 So here is a question for our listeners:那么,我想问问我们的听众:If there were apotion that would allow you to stay young forever, would youtake it?如果有长生不老药,有人愿意吃吗?Thats obvious, Yael?这个问题显而易见,Who wouldnt want to recapture their youth?有谁不愿返老孩童?Im not so sure the answer is obvious.我倒不这么认为。Because the researcher has shown that the olderyou get, the calmer and happier you tend to be.研究人员已经发现人越老越平静、快乐。Wait a second, old age is hard.等等,人老了可不轻松,There is disease, loneliness, and depression.比如:疾病、孤独、抑郁。True, Im not saying that being old age is easy, but social scientists at the University of Texashave found that overall,你说得对,我并不是说人老了轻松,但是德克萨斯州大学的社会科学家发现:aging is associated more with positive, passive emotions instead ofnegative, active emotions.大体而言,老年人情绪更加乐观而被动,并非消极而主动。Passive emotions?被动情绪?Yes, emotions can be passive and active as well as positive and negative. 没错,情绪可分为主动和被动;乐观和消极。So, for example,feeling calm is a passive emotion.比如,淡定就是被动情绪,And its also usually seen as positive.也被看作是乐观情绪。Anxiety and anger, on theother hand, are clearly negative emotions.反之,焦虑和生气很显然是消极情绪。And at least in many cases theyre also active.很多时候,还是主动情绪。Can anger be passive when someone is passive aggressive?因为他人而好斗时,生气就是被动情绪吗?Sure, but the point is that in general, aging seems to make us more emotionally passive.没错,关键是随着人变老普遍的情绪会被动。And being passive seems to correlate more with positive emotions like calm and contentment.而被动情绪和很多乐观情绪相关。Its not clear why aging has this effect, but maybe its because when youre older youre no longer trying to prove yourself, no longer as anxious about getting ahead.比如平静或知足。原因不详,但可能是因为人老了,再也不会试着表现自我,也不会争先恐后。Although, to be fair, the researchers found that the richer and more educated you are, the more you experience positive emotions.公正地说,研究人员还发现越富裕和有文化的人,乐观情绪会更多。 201407/314863深圳市龙华区人民医院打美白针多少钱深圳伊斯佑整形医院整形科



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