-
万物网的英文怎么说
万物网的英文: the Internet of Everything The Internet of Everything is described as something that brings together people, data and things, thus to create networked connections that turns information into action. 万物网指将人、数据和事物汇聚在一起,然后创建成一个相互关联的网络把信息转换为行动。internet是什么意思: n. 因特网;互联网 The internet is a well
-
万物简史:PART III CH 9威力巨大的原子(11)
今天的实验中,那个伟大的实验出现了——α粒子散射实验。被电离的氦原子射向金箔,结果被结结实实地弹回来,就好像一颗38厘米的炮弹被一张纸谈回来一样。如此奇怪的现象让卢瑟福不得不对原子结构传统观念提出挑战——原子内部主要是空无一物的空间,只有当中是密度很大的核~~~ ❤《万物简史》推出部落节目版,戳这里订阅: 文中需听写单词或词组用[-No-]表示,句子用[---No---]表示。请边听写边理解文意,这样可以提高听力准确度,并为训练听译打下基础哦~~~ In 1910, Rutherford (assisted by his student Hans Geiger, who would later invent the radiation detector that [-1-] his name) fired ionized helium atoms, or alpha particles, at a sheet of gold foil. [---2---] To Rutherford's astonishment, some of the particles bounced back. It was as if, he said, he had fired a 15-inch shell at a sheet of paper and it rebounded into his lap. [---3---] After [-4-] he realized there could be only one possible explanation: [---5---] An atom, Rutherford realized, was mostly empty space, with a very dense nucleus at the center. This was a most [-6-] discovery, but it presented one [-7-] problem. [---8---] bears Geiger would also later become a loyal Nazi, unhesitatingly betraying Jewish colleagues, including many who had helped him. This was just not supposed to happen. considerable reflection the particles that bounced back were striking something small and dense at the heart of the atom, while the other particles sailed through unimpeded. gratifying immediate By all the laws of conventional physics, atoms shouldn't therefore exist. 1910年,卢瑟福(在他的学生汉斯•盖格的协助之下。盖格后来将发明冠有他名字的辐射探测仪)朝一块金箔发射电离的氦原子,或称α粒子。盖格后来还成为一个忠实的纳粹分子,出卖了他的犹太同事,其中包括很多曾经帮助过他的人。令卢瑟福吃惊的是,有的粒子竟会反弹回来。他说,他就像朝一张纸发射了一发38厘米的炮弹,结果炮弹反弹到了他的膝部。这是不该发生的事。经过冥思苦想以后,他觉得只有一种解释:那些反弹回来的粒子击中了原子当中又小又密的东西,而别的粒子则畅通无阻地穿了过去。卢瑟福意识到,原子内部主要是空无一物的空间,只有当中是密度很大的核。这是个很令人满意的发现。但马上产生了一个问题,根据传统物理学的全部定律,原子因此就不应该存在。 这篇材料你能听出多少?点击这里做听写,提高外语水平>>
-
万物简史:PART III CH 8爱因斯坦的宇宙(19)
说是"无法解脱地交织在一起"--不可思议地形成一份"时空"。引力--时空弯曲的一种产物。(大家坚持下,物理课快结束了)~~~ ❤《万物简史》推出部落节目版,戳这里订阅: 文中需听写单词或词组用[-No-]表示,句子用[---No---]表示。请边听写边理解文意,这样可以提高听力准确度,并为训练听译打下基础哦~~~ Hints: sag ineluctably The most challenging and nonintuitive of all the concepts in the general theory of relativity is the idea that time is part of space. Our instinct is to regard time as [-1-], absolute, immutable—nothing can disturb its steady tick. In fact, according to Einstein, time is [-2-] and [-3-]. It even has shape. It is bound up—"inextricably interconnected," in Stephen Hawking's expression—[---4---] Spacetime is usually explained by asking you to imagine something flat but pliant—a mattress, say, or a sheet of stretched rubber—on which is resting a heavy round object, such as an iron ball. [---5---] This is roughly analogous to the effect that a massive object such as the Sun (the iron ball) has on spacetime (the material): it [-6-] and curves and warps it. [---7---] This is gravity—a product of the bending of spacetime. eternal variable ever changing with the three dimensions of space in a curious dimension known as spacetime. The weight of the iron ball causes the material on which it is sitting to stretch and sag slightly. stretches Now if you roll a smaller ball across the sheet, it tries to go in a straight line as required by Newton's laws of motion, but as it nears the massive object and the slope of the sagging fabric, it rolls downward, ineluctably drawn to the more massive object. 在"广义相对论"的众多概念中,最具挑战性的,最直觉不到的,在于时间是空间的组成部分这个概念。我们本能地把时间看做是永恒的,绝对的,不可改变的,相信什么也干扰不了它的坚定步伐。事实上,爱因斯坦认为,时间是可以更改的,不断变化的。时间甚至还有形状。一份时间与三份空间结合在一起--用斯蒂芬•霍金的话来说是"无法解脱地交织在一起"--不可思议地形成一份"时空"。 通常,时空是这样解释的:请你想像一样平坦而又柔韧的东西--比如一块地毯或一块伸直的橡皮垫子--上面放个又重又圆的物体,比如铁球。铁球的重量使得下面的底垫稍稍伸展和下陷。这大致类似于太阳这样的庞然大物(铁球)对于时空(底垫)的作用:铁球使底垫伸展、弯曲、翘起。现在,要是你让一个较小的球从底垫上滚过去,它试图做直线运动,就像牛顿运动定律要求的那样。然而,当它接近大球以及底垫下陷部分的时候,它就滚向低处,不可避免地被大球吸了过去。这就是引力--时空弯曲的一种产物。 这篇材料你能听出多少?点击这里做听写,提高外语水平>>
-
万物简史:PART III CH 9威力巨大的原子(12)
裹在原子核里。质子和中子装在原子核里,而电子在外面绕着旋转。质子的数量决定一个原子的化学特性~~~ ❤《万物简史》推出部落节目版,戳这里订阅: 文中需听写单词或词组用[-No-]表示,句子用[---No---]表示。请边听写边理解文意,这样可以提高听力准确度,并为训练听译打下基础哦~~~ Let us pause for a moment and consider the structure of the atom as we know it now. Every atom [-1-] three kinds of elementary particles: protons, which have a positive electrical charge; electrons, which have a negative electrical charge; and neutrons, which have no charge. Protons and neutrons [-2-] the nucleus, while electrons spin around outside. [---3---] An atom with one proton is an atom of hydrogen, one with two protons is helium, with three protons is lithium, [-4-] . Each time you add a proton you get a new element. ([---5---], you will sometimes see it written that it is the number of electrons that defines an element; it comes to the same thing. [---6---]) Neutrons don't influence an atom's identity, but they do add to its mass. [---7---] Add a neutron or two and you get an isotope. The terms you hear [-8-] dating techniques in archeology refer to isotopes--carbon-14, for instance, which is an atom of carbon with six protons and eight neutrons ([-9-]). is made from are packed into The number of protons is what gives an atom its chemical identity. and so on up the scale Because the number of protons in an atom is always balanced by an equal number of electrons The way it was explained to me is that protons give an atom its identity, electrons its personality. The number of neutrons is generally about the same as the number of protons, but they can vary up and down slightly. in reference to the 14 being the sum of the two 让我们稍停片刻,先来考虑一下现在我们所
-
万物简史:PART III CH 9威力巨大的原子(3)
想用肉眼看到草履虫在一滴水里游,你非得把这滴水放大到12米宽。然而,要是你想看到同一滴水里的原子,你非得把这滴水放大到24公里宽。 换句话说,原子完全存在于另一种微小的尺度上。若要知道原子的大小,你就得拿起这类微米大小的东西,把它切成10000个更小的东西。那才是原子的大小:1毫米的千万分之一.这么小的东西远远超出了我们的想像范围。但是,只要记住,一个原子对于上述那条1毫米的线,相当于一张纸的厚度对于纽约帝国大厦的高度,它的大小你就有了个大致的概念。 这篇材料你能听出多少?点击这里做听写,提高外语水平>>
-
万物简史:PART III CH 9威力巨大的原子(4)
也许说明了道尔顿的早熟,也说明了那所学校的状况,也许什么也说明不了。我们从他的日记里知道,大约这时候他正在阅读牛顿的《原理》--还是拉丁文原文的--和别的具有类似挑战性的著作。到了15岁,他一方面继续当校长,一方面在附近的肯达尔镇找了个工作;10年以后,他迁往曼彻斯特,在他生命的最后50年里几乎没有挪动过。在曼彻斯特,他成了一股智力旋风,出书呀,写论文呀,内容涉及从气象学到语法。他患有色盲,在很长时间里色盲被称做道尔顿症,因为他从事这方面的研究。但是,是1808年出版的一本名叫《化学哲学的新体系》的厚书,终于使他出了名。 这篇材料你能听出多少?点击这里做听写,提高外语水平>>
-
万物简史:PART III CH 8爱因斯坦的宇宙(27)
多比银河系要大,要远得多。 仅仅这一项发现就足以使哈勃名扬天下,但是,他接着把注意力转向另一个问题,想要计算宇宙到底大了多少,于是有了一个更加令人瞩目的发现。哈勃开始测量远方星系的光谱--斯莱弗已经在亚利桑那州开始做的那项工作。他利用威尔逊山天文台那台新的254厘米天文望远镜,加上一些聪明的推断,到20世纪30年代初已经得出结论:天空中的所有星系(除我们自己的星系以外)都在离我们远去。而且,它们的速率和距离完全成正比:星系距离我们越远,退行速率越快。 这篇材料你能听出多少?点击这里做听写,提高外语水平>>
-
万物简史:PART III CH 8爱因斯坦的宇宙(26)
也是第一次有人想出了一个计算浩瀚宇宙的实用方法。 (为了合理评价这些深邃的见解,也许值得注意的是,当莱维特和坎农在根据照片上远方星星的模糊影子推定宇宙的基本特性的时候,哈佛大学的天文学家威廉•H.皮克林--他当然能从一流的天文望远镜里想观察多少次就观察多少次--却在建立自己的理论,认为月球上的黑影是由大群大群的、随着季节迁徙的昆虫形成的。) 这篇材料你能听出多少?点击这里做听写,提高外语水平>>
-
万物简史:PART III CH 8爱因斯坦的宇宙(25)
出了一种找到这类恒星的方法。莱维特在哈佛大学学院天文台担任当时所谓的计算员。计算员终生研究恒星的照片并进行计算--计算员由此得名。计算员不过是个干苦活的代名词。但是,在那个年代,无论在哈佛大学,还是在任何地方,这是妇女离天文学最近的地方。这种制度虽然不大公平,但也有某个意想不到的好处:这意味着半数最聪明的脑子会投入本来不大会有人来动脑子的工作,确保妇女最终能觉察到男同事们往往会疏忽的宇宙之细微结构。 有一位名叫安妮•江普•坎农的哈佛大学计算员利用她熟悉恒星的有利条件,发明了一种恒星分类系统。这种系统如此实用,直到今天还在使用。莱维特的贡献更加意义深远。她注意到,有一种名叫造父变星(以仙王星座命名,第一颗造父变星就是在那里发现的)的恒星在有节奏地搏动--一种星体的"心跳"。造父变星是极少见的,但至少其中之一是我们大多数人所熟悉的。北极星就是一颗造父变星。 这篇材料你能听出多少?点击这里做听写,提高外语水平>>
