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2019年09月18日 05:39:15

Shiny and safe, the goal of New York itself.又闪亮又安全,这也是纽约本身的目标。Three decades ago, both the city and the subway shared the bad reputation: dirty, unsafe and no place to be.三十多年前,城市和地铁都享有着坏名声:肮脏、不安全、无人问津的地方。New York cleaned up its image partly by cleaning up the subway.通过清理地铁,纽约重新清理了它的形象。At the Coney Island Yard, they do more than keep the trains running, they keep the Big Apple polished.在康尼岛,他们不只是让火车运营,他们还给大苹果抛光。No job too small, no job too big, lifetime guarantee, how can you beat it? Send us these troubles.没有太小的工作,没有太大的工作,寿命保,你怎么还在犹豫?告诉我们你的麻烦吧。On the subway, keeping car safe is only half the equation.在地铁上,保持车辆只是工作的一半。The system has more than 2600 switches to move trains from one track to another and more than 11,000 signals to control train traffic.该系统具有2600多个开关使列车移动到另一轨道,超过11000个信号来控制列车交通。The equipment is older than most New Yorkers.该设备的岁数比大多数纽约人还老。Much of it was installed before 1940. All together, more than 13,000 chances for something to go fatally wrong. New York cant take that chance.很多都是安装于1940年以前。合在一起, 对于致命错误有超过13000次机会解决。但纽约不能抓住这个机遇。To sidetrack catastrophe, maintenance workers go looking for trouble every day.对于侧线的灾难,维修人员每一天都在寻找麻烦。To find it, the crew themselves must venture into harms way.为了发现它,小组人员必须自己冒着受到伤害的危险。注:听力文本来源于普特201203/174328江西上饶耳部整形多少钱This female grew up on the lake, so she knows where to take the cubs for a very special trip.这只母兽在湖边长大,所以她知道在这次非常特殊的旅行中带幼崽去哪里。Yellowstone cutthroat trout are massing in the mouth of the stream that feeds the lake.黄石鲑鱼在湖口集结。They are preparing for their annual spawning.它们正准备一年一度的产卵。But the trout must wait, the stream is still running fast, too turbulent to lay their eggs.但鲑鱼必须等待,溪水仍然湍急,这种湍流不能产卵。Its a nervous time for them, and for good reason.对它们来说这是一个紧张的时期,而且理由十分充分。注:听力文本来源于普特 201210/204445上饶哪家做鼻子做的好This is like a machine that its always something you need to fix, to oil, to repaint, to clean and possibly to replace.这就像一台机器,总有些东西你需要修理,加油,重新粉刷,清洗及可能的进行更换部件。The Manhattan Bridge needed major repairs at a relative early age. The threat came from the very trains it was built to carry. Held in place by steel cables, the Manhattan has the advantages and drawbacks of a suspension bridge. One advantage, it can flex; one drawback, it can flex. That drawback emerged when the first subway train crossed. As the heavy cars pass, the bridge sways. One side dips, the other rises a full meter. Steel isnt made to flex. The relentless torsion snapped off beams, spanning the lower roadway.在一个相对早期的年龄,曼哈顿桥就需要大修。威胁来自需要承载而建造的火车。钢架构的电缆使曼哈顿的的悬索桥有好有坏。好处是它可以弯曲;缺点也是它能弯曲。当第一次火车通过缺点就涌现了出来。当重型车辆经过,这座桥摇来摇去。一侧下降,另一侧升高。钢本身不是用来弯曲的,啪的一声无情的扭断横梁。The Manhattan Bridge was so neglected, the tracks finally had to be closed for repairs. In the 1980s, the city invested 2.5 billion dollars in a 3-decade program to overhaul its bridges. On the Manhattan Bridge, engineers installed heavy steel braces to stop the swaying.曼哈顿桥如此被忽视,铁轨最后不得不因为进行修理而关闭。在八十年代,这座城市在30年的审查桥梁的项目中投资25亿元。在曼哈顿桥,工程师安装了大型钢架构避免桥的摇摆。The effect is surprising even to us. The rocking motion, really abated.效果甚至对我们而言也令人惊奇。摇摆运动真的减轻了。注:听力文本来源于普特201203/173407Einstein had to be really afraid that Hilbert would actually take over the whole game and publish the final equations of General Relativity before him.爱因斯坦真的担心希尔伯特实际上会接管整个大局并在他自己面前发表最终的广义相对论方程式。All of a sudden, he discovered that several pointers all seemed to point to the same direction.突然,他发现所有矛头似乎都指向同一个方向。Einstein remembered that he had given up a very radical solution that he had stumbled upon aly in 1912 and that he had then discarded because it looks just physically too unfamiliar, too unacceptable.爱因斯坦想起他已经放弃的一个非常激进的解决方案,这个方案他偶然在1912发现,之后又是他自己废弃,因为它看起来很不熟悉,有些不可接受。But now, after he tried out all these other alternatives,但现在,在他尝试了所有这些其他选择后,he was y to return exactly to that equation,他准备重新返回那个等式,back to an equation that he had early considered and then discarded three years before.回到一个他在3年前就曾早考虑过,然后放弃的方程式。You realized that youve been wrong in a real flash of inspiration because you realized what you should be doing.你意识到你在一个真正的灵感瞬间已经错了,因为你意识到自己应该做什么。You know he had it all in his drawer.你知道他在自己的抽屉里有这一切。And thats of course an glorious moment.当然,这是一个辉煌时刻。There it was, the equation that he had discarded.它就在那边, 他已经抛弃了的方程式。And now it was, look much more promising, much more useful than it had in the winter of 1912.而现在,看起来更有前途, 比在1912年的冬天更有用。It isnt always a dark time when you realize that you are wrong,当你意识到你是错误的也并不总是一个黑暗的时代,sometimes its a wonderful time.有时这是一段美好的时光。The excitement for Einstein comes with the realization that the answer for his new theory can be found in an old astronomical riddle.爱因斯坦的兴奋来自他意识到这个新理论的,这在一个古老的天文谜语中被发现。Einstein began to look at a mystery that had puzzled astronomers for generations.爱因斯坦开始寻找一个困扰了天文学家世代的谜。According to Sir Isaac Newton,根据艾萨克·牛顿爵士,the planet Mercury should be going around the sun like this.水星这样绕太阳运行。But it was known for quite a while that the orbit of Mercury deviates from Newtons laws of motion.但是它已经被众人知晓,水星的轨道偏离了牛顿的运动定律。It tilts a little bit.它稍微倾斜。So the orbit instead of going like this begins to tilt and it begins to make a pattern like the petals of a flower.所以轨道而是不继续像这样开始倾斜,它就花瓣一样开始进入一个模式。注:听力文本来源于普特 201205/181683上饶韩美整形美容医院皮肤暗沉怎么样

江西上饶市治疗蝴蝶斑多少钱万年县妇幼保健人民中医院激光祛斑多少钱Winter Wheat冬小麦According to the famous song, America is beautiful for its spacious skies, purple mountains, and amber waves of grain. If you were to make a music based on these lyrics youd probably want mid to late summer images of fruit-laden trees and fields of rippling wheat under sunny blue skies.由那首著名的歌得知,美国因它广阔的天空,紫色的山峦,还有琥珀色的谷浪而美丽。如果你打算取材于这些歌词作曲,那你也许想要夏末载满果实的树和晴朗蓝天下翻滚的麦浪的图像吧。But where the amber waves of grain are concerned, the image might be slightly misleading. While at least some wheat in the ed States and Canada is planted in the spring and harvested in the summer, much is planted in the late fall and harvested in the spring.但是有谷浪的地方,那样的形象也许稍令人误解吧。虽然美国和加拿大或多或少有些小麦是在春天播种,夏天收割,但大部分是晚秋播种,第二年春天收割的。Winter wheat manages to survive freezing temperatures and being buried under piles of snow. How do these plants pull it off?冬小麦设法在结冰的温度下生存,还要埋于厚厚的大雪下。这些作物是怎样成功生存的呢?After being planted in the mid to late fall, winter wheat seedlings undergo a process called cold acclimation. They begin to grow and poke through the soil as the temperature drops to around forty-eight degrees Fahrenheit.在仲秋或晚秋播种后,冬小麦种子经历了被称为冷驯化的过程。它们在气温降到48华氏温度后开始冲破土壤生长。As the plants leaves absorb light the seedlings produce large amounts of carbon and store it in the crown, the part of the plant where root and shoot meet underground.当小麦叶吸收阳光后,种子产出大量的碳并储存在植物冠中,这是根和芽在地底下交汇的地方。At the same time, the absorption of light combined with low temperatures triggers the expression of certain genes that help the plant tolerate freezing temperatures.同时,吸收的光和低温结合促使某种基因的产生,以帮助作物忍耐低温。Although scientists do not fully understand precisely how this process works, it is clear that carbon production and freezing tolerance are necessary for the plants survival.尽管科学家们并未完全准确弄明白这个过程是怎样进行的,但是生产碳和忍受低温对作物的生长很必要,这一点是显而易见的。When the snow melts and temperatures rise in the spring, the plant has plenty of stored energy for steady growth. By mid spring, many North American wheat fields are beautiful with waves of grain y for harvest.春天雪融化,气温也升高了,这时冬小麦已经存储了大量供稳定生长的能量了。到仲春的时候,许多北美小麦地因有大片待收割的小麦浪而美丽无比。 /201211/211204上饶市立医院做隆胸手术多少钱上饶整容吧

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