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齐齐哈尔打胎哪家医院最好的哈尔滨一院收费标准告示Dr. Dolhun had hydrogen peroxide in the plastic bottleDolhun士的塑料瓶中装有过氧化氢Then he added a catalyst, some manganese dioxide然后他加入了一种催化剂,二氧化锰or Mn02 也就是MnO2and got plume of water vapor最后瓶中喷出一缕蒸汽So let#39;s talk about how catalyst works 我们来谈谈催化剂是如何工作的I#39;m going to draw a potential energy diagram for this reaction我将为该反应画一个势能图So here#39;s my potential energy diagram这是我的势能图So we have potential energy on the y-axis 势能位于纵轴上and the reaction coordinate or time on the x-axis 而反应坐标,或者说时间,位于横轴上Reactants are starting at this amount of energy反应物最开始有这么多能量and the products have this amount 而产物有这么多能量Here Ea, that#39;s the activation energy 这里Ea表示活化能It#39;s the amount of energy you need to add to the reactants 需要给反应物提供这么多能量to make the reaction go反应才会发生And ΔH而ΔHthat#39;s the amount of energy that#39;s released when the reaction happens是反应发生时所释放出来能量的量Now let#39;s see what happens when I add a catalyst再看看加入催化剂时会怎样With a catalyst, my activation energy is a lot lower使用催化剂时,活化能大幅降低And even a small reduction in activation energy 哪怕活化能只降低少许can make the reaction go thousands of times faster than it normally would反应也能比通常情况下快数千倍but notice that regardless of whether or not you have a catalyst但要注意,不管加不加催化剂the ΔH, the amount of energy released in the reaction, doesn#39;t change反应中所释放能量的量ΔH是不会变化的So the catalyst only speeds up the reaction 催化剂只加速反应速度It doesn#39;t change the amount of energy released不会改变所释放能量的量Now take a look at this 看看这个Notice the size of the bottles注意瓶子的大小These are very exothermic reactions 这些是放热很多的反应The bottle basically shrunk down to a very very tiny size 同对照组的瓶子比起来,compared to the control bottles瓶子缩小了很多So as you can see, the catalyzed reaction releases so much heat 可以看到,催化反应释放了很多热量that it actually melt the bottles and makes them smaller 让瓶子开始熔化,变小Also the catalyst itself remains unchanged by the reaction另外,催化剂本身在反应中不会变化and designing catalyst is actually a key subfield of chemistry而设计催化剂也是化学中的一个重要领域MIT#39;s Richard Schrock MIT的理查德·施罗克won the Nobel Prize working in this field就因在该领域中的研究获得过诺贝尔奖And remember how we used H2O2 on our cuts?还记得将H2O2涂到伤口的情况吗Well, we have an enzyme in our bodies called catalase 我们人体内有一种酶叫过氧化氢酶that does the same thing as the manganese dioxide that Dr. Dolhun used其作用同Dolhun士所使用的二氧化锰相同That#39;s why when you put hydrogen peroxide on a cut因此将过氧化氢涂到伤口上时you see fizzing and bubbles 会产生嘶嘶声和泡泡The catalase in your blood is breaking down the hydrogen peroxide这表示血液中的过氧化氢酶正在分解过氧化氢And according to recent studies 根据最新研究low levels of catalase may play a role in the greying process of human hair低过氧化氢酶水平在头发变白过程中扮演了重要角色If catalase levels are low 过氧化氢酶水平偏低时it can#39;t break down all the hydrogen peroxide in the blood血液中的过氧化氢就不能被完全分解and that extra H2O2 starts to bleach your hair from the inside out 残留的H2O2会从内部将头发漂白So to wrap up, catalyst don#39;t change the products of the reaction 总结一下,催化剂不会改变反应的产物or how much heat is released or absorbed 也不会改变反应释放或吸收的热量They only change the time it takes for the reaction to finish 催化剂只会改变反应完成所需的时间Alright that#39;s it for me today今天就到这里I#39;ll see you next time 我们下次再见 Article/201501/354534双城市中医院治疗不能怀孕 Alien life could range from simple,外星生物可能还在进化初期green slime that doesn#39;t do much but drip如一些沿石壁流下的绿色粘液 to more advanced animals something with a bit more bite.也可能是相当高等的动物,例如啮齿类动物But, of course, that#39;s just the start of what could be out here.但当然,这不过是最初的猜想In such a massive universe,在如此浩瀚的宇宙中 it#39;s logical to wonder if there are intelligent beings,我们自然会想,是否有智能生物存在perhaps even civilizations like those in science-fiction TV shows and movies.或许还有科幻片里描绘的外星文明;Star Wars; and ;Star Trek,; two of my personal favorites,《星球大战》与《星际迷航》这两部我最爱的电影may be closer to reality than we think.或许远比我们的想象更贴近现实Similar scenarios are at least conceivable.至少很可能拥有相似的情节But think about it more, and even this is limiting the options.但若深思,这其实也大大缩小了现实的可能There could be life forms so strange他们可能外表太过稀奇古怪we wouldn#39;t even recognize them as life.以至我们都认不出那是生物Perhaps there are really exotic creatures that live in center of stars亦或许他们习性奇特,居然生存在恒星的内部or even huge communities of microorganisms他们甚至可能是像宇宙尘埃一般的that look like clouds of cosmic dust.庞大的微生物群落Maybe aliens live and die so fast也许外星生物的生命如此短暂that they come and go in the blink of an eye.由生到死,不过转瞬So in such a vast universe with so many possibilities,总之在如此浩瀚的宇宙中,存在着无尽可能how do we know what to look for or,我们如何知晓要寻找的究竟为何物for that matter, where to look for it?更何况,又该从何入手呢The answer is right back where we began.一切都要回到人类起源之处去探寻The information we need is here at home,我们所需的线索,都在地球之上for the simple reason that home harbors the only known examples of life.只因为唯有此地育着为人所知的生命The laws of physics appear to be the same everywhere,物理学法则似乎放之四海而皆准So it follows that the laws of life should be universal, too.以此类推,生命法则也应如是Even if the detail is different,即使细枝末节或有不同We can use life on earth我们可将地球上生物 as a kind of alien hunters#39; handbook.作为一本了解外星生命的指南手册A field guide to what life actually is, and how it works来引导我们了解生命本质及其机理no matter where it occurs.无论它起源于何处 Article/201505/376173Our solar system, the place we call home太阳系,我们的家园lies about 26,000 light years from the center of our galaxy, the Milky Way.位于距离系中心二万六千光年的地方or around two thirds the way out.或说是系直径的三分之二处The story of how these huge planets came to be orbiting这些巨大行星用了六百万年才开始an average yellow star is six billion years long,环绕一颗中等大小的金色恒星运行and since we don#39;t have that much time, I#39;ll speed it up a bit.由于时间有限,我会加快速度解释过程It starts with a bang.故事的开头是一个大爆炸Long ago an ancient star exploded,很久以前,一颗古老的恒星发生爆炸littering space with swirling clouds of the materials it had made while it lived向空中抛出旋转的它燃烧时产生的物质云团and the heavier metals it created as it died.和灭亡时产生的更重的金属We know this because we我们之所以知道这些是因为can see similar feels of dust out in space today.现今能从星际尘埃中看到相似的感觉They are called nebulae and they are very beautiful.它们叫作星云,形态绚丽多Every nebula is different,每个星云都不同 and in our case the clouds contained nitrogen and oxygen and iron and silicon我们的星云包含氮,氧,铁,硅and all the other stuff needed to build a world like ours.和其他构成丰富多的世界所需的东西Then the tireless force of接着,不知疲倦的万有引力开始gravity started to pull it all back together.将一切牵引到一起And the heavy engineering that produces planets began.创造行星的浩大工程开始了Vast spirals of dust began to form大量尘埃飞扬,开始排列and at the center of one of these,某片尘埃中央a rocky planet called Earth started to take shape,一颗称为地球的岩状行星开始成形built of stardust and assembled by gravity.由星尘为材料,由万有引力组建而成 Article/201509/399836伊春市第一人民医院做药物流产多少钱

哈尔滨市香坊区红十字妇产医院诊所栏目简介:《英国节日简介》是英语视频听力下面的子栏目,栏目通过英式英语视频讲解的形式来介绍英国的节日,能够帮助英语学习爱好者更好地了解英国的节日文化传统,从而加深对英语中一些习惯用语的理解,是提高英语文化素养的好材料。 Article/201510/400265尚志市妇女医院妇产科怎样 I#39;m Bear Grylls. Whoo!我是贝尔·格里尔斯I#39;m gonna show you what it takes to get out alive from some of the most dangerous places on earth.我将让你知道如何 在地球上最恶劣的环境下 逃出生天I#39;ve got to make it through a week of challenges.短短一周内 我将身涉险境 面临生死In the sort of places you wouldn#39;t last a day without the right survival skills.周遭炼狱 没有生存技巧 你命在旦夕 而我要设法突出重围Now I#39;m in Arnhem land, northern Australia where the man-eating,saltwater crocodiles dominate the food chain.我现在身处澳大利亚北部的阿纳姆地 此地 杀人不眨眼的咸水鳄 雄踞食物链之上Man, did you see the size of that?I#39;m hanging on to crumbling sandstone.天 看见它那庞大的身躯了吗 我悬挂在摇摇欲坠的砂岩上And I battle to stay out of the water and away from those hungry crocs.我力竭远离河水 远离那些饥肠辘辘的鳄鱼This old WWII Dakota is gonna drop me into the northern tip of Australia a prehistoric landscape.That#39;s Arnhem land.这是二战时期的达科塔运输机 它我带前往澳大利亚北部的 一块史前的大陆 那就是阿纳姆地I call it prehistoric because Arnhem land is one of those rare places that#39;s remained unaltered since time began.我之所以称其为史前 是因为 这片神秘的土地 远离了现代文明 原住民 土著文化被完好的保留了下来With scorching heat and deadly snakes,it#39;s no surprise that people have struggled to survive here.炎热的气候 致命的毒蛇 人类要在那里生存 无疑是很艰巨的Then at the top of the food chain the flesh-eating crocodile,and there#39;s over a 100,000 of them here.位于食物链顶端的 是见肉眼开的鳄鱼 数量超过10万只And some of those crocs can weigh over a ton.有的鳄鱼体重超过一吨Make one careless move and you#39;re going to end up as lunch.一不小心你就会成为它们的午餐Despite the harshness of this environment,one group developed survival techniques that enabled them to live here.尽管环境极其恶劣 但还是有人研究出了 生存的技巧The aboriginal people have adapted to this dangerous terrain.土著居民们学会了 如何在这个危机四伏的地域中生存And they#39;ve had over 50,000 years to hone those skills.他们掌握了经过5万年历练的生存技巧My task is to use some of their survival techniques and make it out of here alive.我的任务就是运用这些生存技巧 在这里生存下去If you#39;re gonna survive the northern territories,you#39;ve got to throw yourself into it 120%.Here we go.如果你想在北澳生存下来 就必须超常发挥 出发 Article/201612/485328黑龙江省军区妇科医院做输卵管通液多少钱

南岗区妇幼保健院网上挂号布鲁斯·布恩诺·德·梅斯奎塔利用数学分析在预测一些人类突发事件,像战争,政权转变,巴勒斯坦起义等等(通常正确)。进过一番精炼的解释他预测的方法,梅斯奎塔对伊朗局势做出了三个预言。 Article/201508/390335 Officials, scholars gather to discuss security官员学者讨论安全问题To discuss this, we have Senior Captain Zhang Junshe.He is the vice-President of China#39;s Naval Research Institute.为了探讨这个问题,我们请来了中国海军研究所副所长张军社大校谈论有关安全方面的问题。The meeting has focused on security cooperation in the Asia-Pacific region.此次会议的焦点是亚太地区的安全合作问题。In terms of maritime cooperation, in particular, what are the pressing issues to be tackled?尤其在海事合作方面,有哪些需要解决的紧迫问题?And what has China done?中国为此作出了何种贡献?Compared with the previous five forums, what are the major contributions of this year#39;s?与前5次论坛相比,此次论坛有何贡献?Can you share with us your perceptions?能跟我们分享一下您的看法吗? 译文属 Article/201510/404531鹤岗第一人民中医院报价哈尔滨有滴虫性阴道炎能怀孕吗



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