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赣州仁济男科地址查询江西赣州仁济医院做引产需要证明吗Youre hiking through the Rockies one day when you hear a low, ominous rumble. 有一天你正试图徒步穿越落基山脉,这时你听到一种低沉的、不祥的隆隆声。Landslide! Hundreds of tons of rock and soil are careening toward you at enormous speed.是滑坡!数百吨的岩石和泥土眨眼间向你倾泻过来。Fortunately, theres a helicopter nearby and you lift off just in time to escape unharmed.幸运的是附近的一架直升飞机助你逃出生天,多亏及时及时起飞,才免受这一劫难。But now you notice something odd.但你却注意到了一些匪夷所思的怪现象。After the landslide has gone by, in its tracks little dainty flowers are still standing.滑坡过后的地方,小小惹人爱的花朵依然挺拔,Blades of grass are unbent.小草的叶子也没有因此折腰,How is this possible?其中究竟有何奥秘?Before we tell you the answer, heres another question.揭晓之前,先想想另一个问题。What happens when you drop a book flat onto a table?如果你将一本书水平扔到桌面上会发生什么?If you try it, youll see that the book doesnt hit the table unimpeded, but lands on a little cushion of compressed air.你会发现书在撞击桌子的时候并非顺利,而是有压缩空气形成的缓冲垫阻碍。If you dont believe us, try putting some little pieces of paper on the table before dropping the book.如果还持怀疑态度,你大可先在桌上放一些小纸张,然后再将书扔过去。The whoosh of compressed air escaping will blow them off.四散奔逃的受压空气会嗖的将小纸吹走.Thats the same phenomenon that happens with landslides.这就如同滑坡现象的原理。When an enormous sheet of rocks and dirt gets moving, it acts like a solid object.当巨大岩石和泥土块移动的时候,它们就像一个固体。It traps the air underneath it and actually rides downhill on a cushion of air.将空气压在下面的它实际上滚动的时候下面就有了空气垫。Strange as it may seem, much of the landslide never touches the ground at all.尽管听上去有点怪,但大多数山体滑坡从不会和地面接触。Because the cushion of air stays underneath it, the rocks and dirt arent slowed down by friction much and continue picking up speed as they fall.由于空气垫,岩石和泥土并没有受到擦力影响而减速,相反会不停地加速。Large landslides have been clocked in excess of 100 miles an hour.规模大的山体滑坡时速超过每小时100英里。So-could you just lie down and let the landslide whoosh over you?那么你能躺下来让滑坡从你身上呼啸着越过吗?No, unless you are about the size of a blade of grass.这可不行。除非你只有草叶般大小。People who are bigger than that should keep a helicopter handy. 因此比草叶体积大的人应该随时让一架直升飞机在身旁待命。 201311/262971崇义人民医院好不好 If youre planning a trip to Greece in the future, youll want toschedule a visit to the temple of Apollo at Delphi.如果有一天,你打算去希腊旅游,你可能会将特尔斐的阿波罗神庙列入行程单。This famoustemple was the home to the Pythia, a specially chosen andtrained woman who, according to legend, channeled the voiceand wisdom of Apollo, the god of prophecy.阿波罗神庙的女祭司皮提亚,传说,皮提亚是掌管预言的阿波罗神钦点传达预言和智慧的女祭司。Generals,politicians, and private citizens of the ancient world flocked to Delphi to question the Pythia andseek her divinely inspired advice.古时候,将军、政治家、普通百姓蜂拥而至,只为求得宣示的神谕。Ancient scientists and philosophers attributed the oracles power to vapors that bubbled upthrough a chasm and spring running through the oracles chamber inside the temple.古代的科学家和哲学家称,神谕的力量来自从深坑冒出的袅袅蒸气以及神庙内殿神龛喷出的泉水。Inhalingthese vapors, according to the ancients, induced a trance-like state that endowed the oracleswith divine prophetic power.祖先们认为,吸入气体,飘飘欲仙,并赋予了神圣的预言神力。Around 1900, excavations at Delphi revealed no chasm orescaping gases, and so the ancient accounts were discredited.直到公元1900年,科学家挖掘遗址,并未发现所谓的深坑,也没有飘散的气体。实前人的记载并非属实。Until recently, that is Geological surveys of the area have detected two faults, or cracks in theearths crust, intersecting directly under the oracles chamber.直至最近,在对当地进行考察中,发现了地壳有两道断层或裂缝,正好交错于神庙内殿神龛下面。Samples from Delphic spring waterand rock from the intersecting faults revealed traces of several chemicals including ethylene.特尔斐泉水的样本以及断层裂缝岩石的样本中提炼出几种化学物质,其中包括乙烯。Tests have shown that when administered in proper dosage, ethylene can result in a trance state.实验显示,适当剂量的乙烯使人精神恍惚,Those affected are conscious, able to sit upright, can answer questions, and afterwardsexperience amnesia.但是神志清醒,可以笔直地坐着,可以回答问题,但是可能很健忘。Some subjects react violently, screaming and throwing themselves about.有些个体变得很暴力,大吵大闹,疯疯癫癫。Such reactions to ethylene are consistent with ancient reports.这些对乙烯的反应和前人的记载吻合。Unlike their Greek predecessors,modern scientists leave Apollo out of the picture.与希腊的祖先不同,现代科学家慢慢解开了阿波罗神庙的面纱。But once again, science gives at least partialcredence to something that was once considered only a myth.至少,曾经我们对曾认为是神话的事情有所了解了。201407/310283赣州安远私密整形哪家医院好的

章贡医院人流价格表Science and technology科学技术Military camouflage军事伪装That old razzle dazzle旧式迷魂战术How to confuse the enemy about how quickly you are travelling如何让敌方无法判断己方的前行速度Go-faster stripes?船身高速伪装线?IN THE second world war, many Allied ships were painted with dark and light stripes,and other contrasting shapes, making them look a bit like zebra.二战期间,许多盟军军舰船身都被喷涂了黑白条纹及其它迷图案,这让它们看上去有些象斑马。The idea was to distort an enemy submarine commanders perception of the ships size, shape, range, heading and speed, so as to make it harder to hit with the non-homing torpedoes of the period.这样做的目的是为了迷惑敌军潜水艇指挥官,使其无法判断盟军船舰的尺寸,形状,距离,航向和速度。由于当时的鱼雷还不具备制导系统,因此想要击中目标愈加困难。These had to be pointed not at the target directly but, rather, at the place where the commander thought the target would be when the torpedo arrived.因此敌军指挥官不再让鱼雷直接对准目标发射,而是将它们发射到他认为盟军军舰可能会驶向的位置。At the time, though, it was only an educated guess that this so-called dazzle camouflage would work.当时, 对于这种所谓的迷伪装术的有效性判断还只是基于经验上的考量。Now someone has actually tested it and the short answer is that it does work—but not in the way that Allied navies thought it did.而如今已经有人对此进行了真实测试,结果验这种迷伪装的确有效—但并不是按照盟军海军所设想的那种方式发挥作用。Ships move too slowly for dazzle camouflage to be effective.迷伪装无法保护航行速度过慢的船艇。However, it might well have a role in protecting faster-moving vehicles, such as military Land Rovers.但它对于军用路虎这样快速行驶的车辆却能起到很好的保护作用。Nicholas Scott-Samuel, of the University of Bristol, and his colleagues, came to this conclusion by asking volunteers to watch patterned rectangles cross a computer screen.以上结论是由布里斯托尔大学的Nicholas Scott-Samuel和他的同事通过实验得出的。Some of the rectangles had horizontal stripes inside them.他们让志愿者观察在电脑屏幕内横向移动的长方形物体,这些物体内部被喷涂了不同图案,Some had vertical stripes.图案形式有横纹,Some had zigzags.竖纹,And some had checks.锯齿纹和方格纹。Others, acting as controls, had no internal patterns.而作为参照的物体则未喷涂任何图案。Each test involved a jazzy rectangle crossing the screen either before or after a plain one.每次实验志愿者在观看了迷图案的长方形横过电脑屏幕之前或之后,还被要求观看一个没有条纹图案的物体横过屏幕,Volunteers had to estimate which of the two was travelling faster.之后志愿者需要估计这两个物体哪个移动速度较快。In fact, in all cases, the two rectangles travelled at the same speed.实际上,在所有实验中,这两个长方形物体移动的速度都相同。But the researchers varied the conditions in other ways, without telling the participants.但研究人员通过其它方式改变了实验条件,志愿者对此却一无所知。Sometimes both rectangles travelled slowly, at just over 3o of arc a second from the observers point of view, as a ship might.有时两个长方形物体移动速度都很慢,从志愿者的观察角度看,就象一艘船以每秒驶过3度的距离在航行,Sometimes they travelled much faster, at 20o a second, mimicking the way a land vehicle moves.有时它们都模仿陆地车辆行驶方式以每秒走过20度的距离快速移动。The jazzy rectangles also came in different flavours. Some were low-contrast and some high-contrast.长方形物体的迷图案也不尽相同,有些图案对比度不强烈,有些图案的对比度则很强。The upshot, as Dr Scott-Samuel reports in the Public Library of Science, was that participants were not fooled by slow-moving rectangles, nor by low-contrast ones.实验结果如同Scott-Samuel 士在公共科学图书馆报告所说,志愿者对慢速移动或图案对比度不强的物体移动速度判断较准确。Fast-moving, high-contrast shapes, however, did befuddle them.而对于快速移动和图案对比度强烈的物体,他们的判断常常出错。On average, an observer reckoned that such a fast, jazzy rectangle was going 7% slower than was actually the case.志愿者对于有迷图案和快速移动的正方形物体的速度估计要比它们的实际速度平均低了7%。Ships, therefore, travel too slowly for dazzle camouflage to work.因此喷涂迷伪装的军舰航行速度过于缓慢是起不到迷惑敌军作用的。In any case, modern torpedoes and missiles are guided to their target electronically.在任何情况下,现代的鱼雷和导弹都采用了电子制导来跟踪目标。But 20o a second corresponds to the perceived movement of a vehicle 70 metres away that is travelling at 90kph.但是从视觉角度看,每秒20度的移动速度相当于在70米外看到一部车辆在以90公里/小时行驶。That is precisely the sort of distance from which an unguided rocket-propelled grenade might be fired at a lightly armoured military vehicle, and just the sort of speed such a vehicle might be travelling at.在与此相同的距离和速度条件下,一个非制导火箭推进榴弹能够击中一辆轻型装甲军车。Perhaps the answer, then, is for modern armies to buy their Land Rovers second-hand from game parks, which often paint them in zebra stripes for effect.如果果真如此,那么现代军队可以考虑在狩猎公园买个涂有斑马条纹的二手路虎车了。Whether real zebra got their own jazzy stripes to confuse predators has yet to be determined.至于斑马身上的条纹能否让其躲过掠食动物的捕杀则还有待实。 /201304/235805兴国县妇女儿童医院农保能报销吗 全南妇幼保健院白带常规多少钱

赣州定南妇幼保健院妇科是公立医院吗And all this meat in one small area attract the scavenger, the short-faced bear. Led by his super sensitive nose, his long limbs carry him many miles a day in search of carrion. Hes picked up a scent, but wheres the carcass? Sometimes the smaller, speedier scavenger gets there first, on this occasion a coyote.在这一小片区域的腐肉吸引来了短面熊,腐肉是它的主食。凭借极度敏感的嗅觉和长长的前肢,短面熊为了寻找腐肉能一天行进数英里。它闻到了气味,可肉在哪?有时,体型更小,速度更快的食腐动物能够更快找到腐肉,这次恰恰是一只丛林狼。Right now the short-faced bear will take whatever he can get. He hasnt had a decent meal in days, and needs at least one good-sized carcass every week to stay alive. This time the coyotes left him nothing but the skeleton. But with his huge, bone-crunching jaws, the bear can crack them open for the marrow locked inside.现在,这只短面熊已经变得饥不择食。它数日没有吃到一顿像样的了。为了存活,它每周至少吃一只大型动物的尸体。这次,这只丛林狼除了一个头骨什么也没有留下。但是短面熊的巨掌能将骨头拍碎,它可以拍开头骨,吃到头骨里面的精华。With water so scarce elsewhere, animals from miles around converge here in the valley, which is good news for the local lions—their pride territory is now overflowing with food.由于其他地区水源缺乏,几英里外的动物们纷纷聚集在这片山谷里,这对山谷里的狮子们来说是一件好事,因为他们引以为傲的领地中到处都是食物。Once the midday heat subsides, the females rouse themselves to hunt.一旦正午的炎热过后,雌性狮子们便会出去觅食。英文文本来自普特英语,译文属.201305/241870 定南医院网上预约电话赣州兴国医院几点开门



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