厦门胎记医院较好
时间:2019年08月18日 19:08:59

By piecing together the evidence these creatures left behind, we can build a picture of this sub-tropical corner of the continent as it was 13,000 years ago. While most of North America was still in the grip of the Big Freeze, Florida was an ice age oasis. Florida is aptly named the Sunshine State. With an average of eight hours of sun a day, it seems a world away from any ice age. Even 13,000 years ago, the massive ice sheets were hundreds of miles away to the north. So what was it like back then? 将这些动物遗留的痕迹拼凑到一起,我们可以探索到13,000年前这个位于亚热带大陆角落的区域的面貌。北美洲的大半部分都属于“大冻结”区域,而弗罗里达却是冰河时代的绿洲。称佛罗里达为阳光州再适合不过了。日照日均长达8小时,这似乎与冰河时代格格不入。即使在13,000年前,大面积的冰原距离它也有上百英里。那么它当时又是什么样子呢?To investigate Floridas ice age past, one of the best places to look is under ground and up the water. Just below the surface lies a very strange world. Millions of years of water action has dissolved the limestone rock, forming a system of flooded caves and tunnels. This vast underground network runs for thousands of miles. Much of Florida is basically a big rock honeycomb. In places the water is forced to the surface, forming springs. Florida has one of the largest concentrations of springs in the world. Filtered through sand and rock, the water is crystal-clear. And welling up from deep within the earth, it is a constant 22 degrees centigrade.想要了解弗罗里达冰河时代的过去,最好的去处之一便是“地下”和“水上”之间的空间。在地表下面便存在着一个奇异的世界。数百万年的水流运动溶解了石灰岩,形成了积水溶洞和隧道。这一片地下网络延绵数千英里。弗罗里达的大部分地区基本上就是像蜂巢一样的岩石区域。部分区域的地下水被挤到地表,形成了喷泉。弗罗里达是世界上喷泉最密集的区域之一。从沙土和岩石中流淌的泉水晶莹剔透。这些泉水地底喷出,恒温达22摄氏度。英文文本来自普特英语,译文属.201307/248382

Youve just opened a bottle of wine for dinner.设想一下,你在晚餐时刚刚打开了一瓶酒,On the label,you see these words: Contains Sulfites.你会在酒瓶的标签上看到:含亚硫酸盐。What are sulfites?亚硫酸盐是什么?And what are they doing in your wine?这些成分在你的酒中发挥什么样的作用呢?Sulfites are chemical compounds found naturally in grapes, garlic and other plants.亚硫酸盐是在葡萄,大蒜和其他植物中常见的一种化合物。Thousands ofyears ago, people realized something nifty about sulfites: they kill or slow the growth of bacteriaand most yeasts.几千年前,人们就发现了亚硫酸盐的一些妙用:它们能杀死细菌,或者降低细菌滋生和发酵的速度。This comes in handy for winemakers, who add specific yeasts to ferment wine,and dont want wild yeasts or bacteria to spoil it.这个发现对于酿酒师来说是非常重要的,他们通常会在酒中加一些特定的酵母使酒发酵,但是同时,他们又不想野生酵母和细菌破坏了这个过程。Sulfites prevent spoilage in wine, acting as apreservative.而亚硫酸盐就能阻止酒的腐坏,在其中发挥了防腐剂的作用。The amount of sulfites naturally in grapes is very small, and theres a bit more produced duringfermentation.葡萄中含有亚硫酸盐的量非常少,在发酵过程中数量会有稍许的增加。But to take full advantage of sulfites preservative abilities, winemakers add a littlemore to the process.但是,为了有效利用亚硫酸盐的防腐作用,酿酒师们通常会在酿酒过程中多添加一点点亚硫酸盐。The Egyptians sterilized wine containers with sulfites, and sulfites have beenadded to wine for hundreds of years.埃及人也曾使用亚硫酸盐对酒类容器进行杀菌,而且,亚硫酸盐被添加进入酒类也已经有了几百年历史了。So the relationship between wine and sulfites goes way back.因此,酒和亚硫酸盐的关系其实可以回溯到很久很久以前。But in 1985, the Food and DrugAdministration required wine with added sulfites to say so on the label. Why?但在1985年,食品与药品要求,若酒类有添加亚硫酸盐,需要在标签上注明,为什么?Researchers had recently discovered that less than one percent of the population is sensitive tosulfites.因为有研究人员之前发现,有不到1%的人会对亚硫酸盐产生过敏反应,Most have mild reactions, like an itchy rash.虽然多数人的反应比较轻微,比如说会起很痒的皮疹,But some folks have life-threatening reactions,including difficulty breathing and low blood pressure.但有部分人的过敏反应会威胁到生命安全,这些反应包括呼吸困难或低血压等。These rare but serious reactions are most often seen in asthmatics.我们经常会在哮喘症患者身上看到这些少有但严重的反应。Not all asthmatics are sensitiveto sulfites, but the labels there for those who need to steer clear.其实,也并不是所有的哮喘症患者都会对亚硫酸盐过敏,标签上的说明只是为了警示需要注意的人避开这些成分。As the old saying goes, inwine–and now on the label–there is truth!就像老话常说的那样,酒后,现在是标注在标签上吐真言! 201402/277827

Science and technology科学技术3D printing3D打印A new brick in the Great Wall构筑长城的新砖石Additive manufacturing is growing apace in China中国的叠层制造正在飞速发展ALTHOUGH it is the weekend, a small factory in the Haidian district of Beijing is hard at work.虽然是周末,北京海淀区的一座小型工厂还在努力地运转着。Eight machines, the biggest the size of a delivery van, are busy making things.厂里的八台机器正在忙碌地制造产品,最大的机器有厢式货车大小。Yet the factory, owned by Beijing Longyuan Automated Fabrication System, appears almost deserted.然而这家隶属于北京隆源自动成型系统有限公司的工厂看上去就像废弃了一样。This is because it is using additive-manufacturing machines, popularly known as three-dimensional printers, which run unattended day and night, seven days a week.这是因为工厂使用的是叠层制造设备,即广为人知的三维打印机,可以一周七天,不分昼夜的无人化运转。The printers require an occasional visit from a supervisor to top them up with the powdered materials they use as their inks, or to remove a completed item, but apart from that they can be left on their own.这些打印机需要管理员不定期的来为其加满粉末状原料,作为它们的墨水,或者取走完成的物品,但除此之外,这些打印机可以自行运转。They build up the objects they are making one layer at a time, as the ink is sintered into place with a laser in a way that creates little waste and can make shapes impossible to achieve using the traditional subtractive technology of lathes, milling machines and cutting tools.它们一次一层的逐步构造物品,用激光以一种不会产生什么废料的方式将墨水在适当位置烧结,可以做出采用传统削减技术的车床、铣床、刀具不可能做出的形状。Though it is not yet y for use in mass production, 3D printing is excellent for making prototypes, customised jobs and short production runs, for there is no need to retool each time the specification changes.虽然3D打印目前不能用于大批量生产,但3D打印非常适用于制造原型件,定制加工及小批量生产,因为改变规格时不需要每次都更换刀具,All that need be done is to alter the software that controls the print heads.需要的只是更改控制打印头的软件而已。Western countries led the development of 3D printing, and the technique has been praised by Barack Obama as a way to revive Americas manufacturing industries.西方国家引领了3D打印的发展,该技术还被巴拉克·奥巴马誉为复兴美国制造业的一种途径。It may yet do so.3D打印或许能不负所望。But the extent to which that revival will be brought about by the return to America of production which has migrated to countries like China is harder to predict—for China has plans of its own.让以前转移到像中国这样的国家生产的产品回到美国生产会带来复兴,但复兴的程度更难预料——因为中国也有自己的计划。Keep your powder dry做好一切准备At the moment AFS is in the prototyping business.目前AFS从事的是原型设计业务,Its customers are mainly aerospace firms and vehicle-makers that need experimental designs turned into metal quickly.其客户大多是需要将实验设计快速转化为金属实样的航空公司及汽车制造商。The powders in its machines hoppers are plastics, waxes and foundry sand.其设备料斗中的粉末是塑料,蜡及铸造用砂。The results are sent off to foundries, where they are used to make moulds for the sand-casting of metal objects.完成品送到铸造厂,用来制作金属件砂模铸造用的模具。According to William Zeng, AFSs deputy general manager, all the parts needed to make a prototype car engine can be printed and cast in this way in under two weeks.据AFS的副总经理William Zeng称,制作一个汽车引擎原型所需的全部零件均可以这种方式打印并铸造,用时不到两周,A conventional machine shop would need several months to do that—not least because many of the components would have to be made by hand.而传统的机工车间需要数月时间才能做到——主要是因为许多组件需要手工制作。AFS also has a second line of business. It sells the laser-sintering printers it makes to others, for this is a rapidly growing industry.AFS还有一块副营业务,即将其制造的激光烧结打印机出售给其它公司,因为这是一个飞速增长的行业。And some of its machines, which cost up to 1.5m yuan, can do more than just sinter plastics, wax and sand; they can sinter metals directly.其某些设备的售价高达150万元人民币(约合25万美元),不只可以烧结塑料,蜡和砂子,还可以直接烧结金属。Indeed, one of the countrys largest 3D printers does just this.实际上,中国最大的3D打印机也有此功能。It is 12 metres long and it belongs to the National Laboratory for Aeronautics and Astronautics at Beihang University.该设备长12米,拥有者是北京航空航天大学的航空航天国家实验室。Wang Huaming, the laboratorys chief scientist, told a digital-manufacturing seminar organised recently by the Laboratory of High Performance Computing, a government research institute, that this behemoth is being employed to make large and complex parts for Chinas commercial-aircraft programme, which plans to build planes to rival those turned out by Airbus and Boeing.该实验室的首席科学家王华明最近在一次由高性能计算实验室组织的数字制造研讨会上说,这个大家伙是为中国的商用飞机项目制造大型复杂部件的,该项目计划制造出可以与空客和波音制造的飞机匹敌的飞机。These parts include titanium fuselage frames and high-strength steel landing-gear—objects that require the metal they are made from to be free of flaws which might cause them to fail.这些部件包括钛机身骨架及高强钢起落架,制造这些部件所用的金属要求没有任何瑕疵,否则会导致部件无法使用。Printing such things, rather than making them from precast metal, will be a technical tour de force, and Dr Wangs team is therefore working on the tricky problem of controlling the recrystallisation of metals after they have been melted by the laser.打印这些部件,而不用预制金属制作,将会是一项技术绝活,因此王士的团队正在致力解决的棘手问题是激光将金属熔化后对金属重结晶的控制。Making planes is about as high-tech as mechanical engineering gets.制造飞机算是机械工程中的高科技。But 3D printing in China is also busy at the other end of the market: extruding filaments of molten plastic to build up objects such as toys, mobile-phone cases and car fittings.但是3D打印在中国还广泛应用于其他市场:挤出熔融塑料的细丝来逐步构造出如玩具,手机壳及汽车配件等物品。One of the biggest firms in this field is Tiertime, which operates from Huairou on the outskirts of Beijing.位于北京市郊怀柔区的太尔时代是该领域最大的公司之一。Tiertime makes a range of 3D printers that produce objects from polymeric alloys of acrylonitrile, butadiene and styrene.太尔时代生产一系列3D打印机,可以用丙烯腈,丁二烯和苯乙烯的聚合物合金制作物品。Tiertimes printers are also often used in the prototyping business, but unlike those of AFS they sit in designers offices rather than on factory floors.太尔时代的打印机也常用于原型设计业务,但与AFS的设备不同,太尔时代的设备是置于设计师的办公室,而非工厂的车间里。Some are small enough to sit on a desk.有的设备小到可以放在桌子上。They allow people to print their ideas directly, rather than having to.这让人们可以直接将自己的创意打印出来,而不用将创意发出去让别人制作。The company also makes even smaller printers, called UP, which sell for less than 6,000 yuan.太尔时代甚至还可以制造更小的打印机,叫做UP,售价不到6000元人民币。Personal printers like these are helping to create a Chinese version of the maker movement—a mixture of hobbyists and craft producers who, finding that 3D-printing technology greatly lowers the cost of going into production, are creating small manufacturing businesses.类似UP的个人打印机正在促进中国版创客运动的形成,即一批发现3D打印技术极大的降低了投产成本的业余爱好者及工艺品制造者正在纷纷建立小型制造企业。The maker movement began in America, but it is taking off in China too.创客运动始于美国,但在中国的创客运动也在迅速发展。Maker fairs are now being held in some of the big cities. Officials seem happy to encourage this, and some talk of introducing 3D printers into schools, to spark pupils interest in careers in engineering.某些大城市现在正在举办创客展会。官方似乎乐于持创客运动,某些官员谈及将3D打印机引入学校,激发学生从事工程职业的兴趣。3D printing is still a long way from replacing mass manufacturing. But in China, as in America and Europe, the technology is changing the way products are developed and made.3D打印要想取代大批量生产还有很长一段路要走。但在中国,与在美国和欧洲一样,该技术正在改变开发和制造产品的方式。And by lowering the cost of entry, 3D printing could herald yet another new generation of Chinese manufacturing entrepreneurs.通过降低成本门槛,3D打印或许能创造出新一代的中国制造业企业家。 /201312/267007

The results are spectacular.结果非常惊人。Thanks to their super-nutritious diet, queen bees grow up to one and a half times larger than regular bees, live forty times longer than normal bees, and lay up to two thousand eggs per day.由于超有营养的饮食,蜂王长大后的身体比工蜂长1/3,寿命是工蜂的40倍,每天产卵2000个左右。Inevitably, entrepreneurs have attempted to capitalize on royal jelly by creating jelly-infused dietary supplements that supposedly make people stronger and more virile.必然地,企业家们试图利用蜂王浆牟利。他们大量制作注入浆状物的营养保健品,大概能使人的身体更强壮和更有男子气概。But dont go sping royal jelly on your toast just yet.但别马上把蜂王浆涂到烤面包上。Although it does the trick for bees, theres no solid proof that the stuff will make you king or queen for even a day.尽管它对蜜蜂管用,但并没有确凿的据明它能够让你成为哪怕一天的国王或女王。 201312/267980

Research shows that whether a person is an optimist or apessimist is related to their quality of life, including their physical health.研究表明,不管一个人是乐观还是悲观,都他的生活质量息息相关,包括身体健康。The subjects involved first took personality tests in the1960s and then thirty years later they completed a follow-up self-assessment of their healthstatus.这个主题首次在二十世纪六十年代提出并做了人格测试,三十年后他们后续完成了健康状况的自我评价。Researchers found that not only did the optimists from the 1960s report better physicaland mental functioning thirty years later, but that optimists also lived longer on average than pessimists.研究人员发现60年代的乐观主义者不仅身心比30年后的人更健康,而且乐观主义者比悲观主义者更长寿。Its hardly clear that there is a causal relationship between optimism and health.很难理清乐观与健康之间的因果关系。it could be thatthey are related to the same underlying gene complex or set of mechanisms.也许是因为它们与相同的潜在基因或是一套机制有关。Still, it sure istempting to surmise that its partly a positive attitude that keeps people alive for so long.不过,可以肯定的是,一定程度上的积极心态能让人长寿。It mayactually be possible that a lot of what my parents have been telling me for years is true.实际上可能多年来我父母告诉我的许多事情都是真的。If you think positively, good things may happen to you.如果你积极地看待这个世界,好的事情就可能发生在你身上。If you think negatively, then you may doomyourself.如果你总是消极地看待一切,那样只会让你自己更郁闷。 201408/321927


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