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C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | Evolution of life on the Earth has been by no means uniform; there have been periods of waxing and waning which may be attributed to geographical, climatological, and biological influences. The development of large land areas, ranged longitudinally or latitudinally, the invasion of epicontinental seas, the isolation of... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | On the establishment of the grasses, we find that groups of animals, which had previously browsed on shrubs and trees, adopted them, with consequent alterations and adaptations in their teeth and other bodily structures. To follow their food from over-grazed or sun-scorched regions they required to be able to migrate e... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | It is perhaps not too much to say that the magnificent outburst of energy put out by the Earth in the erection of the Alps, Andes and Himalayas in Tertiary times, was trivial in its influence for man's advent and his successful occupation of the Earth in comparison with the gentle but insidious growth of “mere unconque... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | The proportion of brain to body improved in those reptiles which took to flying, possibly in relation to their acquisition of warm blood, and in the birds evolved from reptiles; but it is only in mammals that a marked advance is seen. Here the brain of Uintatherium
, a great rhinoceros-like animal of Eocene date, weig... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | When we contemplate the time and energy, the sacrifice and devotion, that this evolution has cost, we must feel that we are still far from the end of this mighty purpose: that we can confidently look forward to the further advance which alone could justify the design and skill lavished on this great task throughout the... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 英文
《人类始祖》一书表明,到1863年时,赖尔其实已经转变了原来的观念,随后他重新编写了《地质学原理》第二卷中的许多内容,并纳入了这种新的观点。因为这一改变,胡克在1868年的致辞中对他给予了高度评价。这对于一本科学著作来说即便不是空前绝后,也一定是有史以来最高的奖励了:
“我再也找不出比这更能诠释勇敢的例子了,一位作者在晚年放弃了一个理论,而这个理论曾被他视为自己著作的基石之一,要知道这一著作曾给他带来同时代科技著作者所能获得的最高荣誉。他可能曾经以这种建立在并不可靠的学说之上的作品为骄傲,但后来他发现新的学说可以更好地支撑其理论,便对先前的工作做了修改:当全部工作完成时,再审视自己的作品,不仅比以前更可靠,而且各部分之间也更... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 修斯认为,这些变迁的规模之大是当今陆地边缘处的微小隆起和下沉所远远无法比拟的,并且无法用这样的现象对其进行解释。他认为,现今的陆地起伏多数是由火山、地震或者其他一些事件造成的,比如,冰川环境下冰盖对弹性地壳的荷载或者释压等。
英文
这时修斯有必要利用世界范围内海洋相对于陆地的周期性涨落来取代或补充地壳的震荡运动;正向运动,即海进时,会携带海水及其沉积物于陆地之上,将陆地以及陆地的轮廓淹没在数十至数百英寻的海水之下;而当负向运动,即海退时,海洋会向深处退缩,留下光秃秃的或者覆盖了一层新沉积物的陆地。
英文
尽管这种概括较好地解释了一些事实,但修斯未能提供这种奇妙节律的产生机制。这个问题非常困难,因为液体会始终保持在一个水平... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 英文
赫胥黎在1869年地质学会上的演讲中挑战了这一难题,他一针见血地指出:“难道地球仅仅是一个在不断变冷的物体,‘就像马车上用的热水罐’或者‘一块球形砂岩’么?”同时他还认为,至少存在一些作用可以使地球的热量再生或延缓其衰减。
英文
所以,我们只能说,这位给地质年代加上了一个狭窄界限的伟大物理学家,为后继的物理学家们做了准备工作,后者已经证明,地球在它的放射性物质中存储了一种“隐藏的储备”,这使得由于放射性而损失的能量可以持续再生,并由此延长完全衰变所需要的时间。后来的这些物理学家推算出的地球年龄要长得多;尽管对于宇宙进化论者和天文学家们来说这段时间是微不足道的,但已经比我们原先预想的要长得多了,以至于我们为突然涌入自己手... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 第二,膨大的地壳不足以被收缩的地层下部所支撑,还将受到强烈的剪应力作用,从而导致地壳表层如干瘪的苹果皮一样布满褶皱。这些褶皱会在薄弱地带,例如沿着大陆的边缘形成山系;山系不断地堆积和升高,而裸露出来的被抬高的岩石则面临着水作用带来的强烈侵蚀。
英文
就这样,我们又找到一种修斯所需要的机制,而且该机制确保了陆地和山脉的运动之间的必然关系,以及陆地的广泛扩张和与火山、地震及其他侧向逆冲现象相伴的山脉崛起之间的必然关系。
英文
如此,一次热循环算是完成了它的全过程,从固态的地层下部开始,经过一段时期的液化,其间伴随着地壳拉张,最后再回到固态和侧向应力作用的时期:当然这一阶段又是一个新的循环的开始。
英文
阿瑟·霍姆斯教授... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 其实只需稍加想象,在此基础上再发挥一点儿创造力和灵活性,那么大西洋两岸的平面图或地图就变得非常吻合了,尤其是当我们将实际的大陆边缘,即将“大陆架”与大洋深处分割开来的陡峭的斜坡绘出并拼到一起的时候,上述结论就变得更加明显了。这表明大西洋两侧曾经很可能是一体的,只是后来发生破裂并漂移开来,直到现在被大洋所分开。
英文
这个前人总结出的观点,后来得到魏格纳的特别强调,并在其著作《海陆起源》一书中做了详细分析,现在这一观点已成为魏格纳大陆漂移学说的最核心部分。该学说得到了许多证据的广泛支持,包括:欧洲西部和大不列颠岛与北美东部多个地质时期的化石和岩石极为相似;影响这些岩石的构造是一致的;此外,两岸现存动植物也表现出强烈的相似性,由此... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 英文
如果承认了冈瓦纳古陆的漂移这一假设,那么否定这一原则在其他地区包括北大西洋地区的应用就是不符合逻辑的。关于这一点,我在前面已经提到了一些有利的事实。此外还包括:北大西洋两侧从石炭纪到奥陶纪、从泥盆纪到三叠纪的所有沉积岩都非常相似;大陆构造之间的联系,例如,纽芬兰岛和爱尔兰之间;以及贝利教授在1928年C分会的致辞中给出的那个例子。正如贝利当时指出的那样,巨大的加里东山脉从斯堪的纳维亚起,由东北向西南依次穿过苏格兰、北英格兰以及威尔士,它受到东西向的从布列塔尼延伸至南威尔士的阿莫里凯(海西)山系的影响,并发生位移。“两列山系的交叉始于不列颠群岛,止于新英格兰”;阿莫里凯山系从新英格兰又继续向西延伸。根据魏格纳的理论,如果将北美... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 因此归根结底,大规模的运动已是不争的事实,而接下来的问题是,我们能够在多大程度上接受魏格纳所设想的大陆漂移理论,或是其改进的版本。我们需要通过我们自己的观察来审视和检验所有的数据,我们确信伽利略的那句名言同样适用于我们的工作,那就是“地球依然在动着”。
英文
岩石的褶皱与山脉的诞生
岩石的倾斜与褶皱是由于侧向或剪应力作用而不仅仅是抬升作用的结果,当人们认识到这一点以后,地球内部相对于地壳的收缩就被视为这种运动的主要原动力,并且,套用任何一个现已得到承认的理论,我们都不能否认这个强有力的原动力的效力。
英文
山脉形成过程中各事件发生的一般过程已为大家所熟知,即:在相当长的一段时间内,地壳中向下褶皱的缓慢下沉;沉积物对下沉区... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 在他有生之年,他看到了自己的梦想都变为现实,因为他组建的这个团队吸纳了众多优秀的调查员、研究人员、作家和教师,其中包括普莱费尔、洛根、拉姆齐、阿夫利娜、朱克斯、福布斯、珀西、胡克、以及赫胥黎等人。
英文
亨利·德拉贝什的部分设想已变为现实并发展壮大成为重要的机构,同时为科学记录、教育和研究等方面提供了重要的帮助。不过地质调查局的主要职责没有变,迄今已履行了一个世纪之久。这些职责就是,以尽可能大的比例尺绘出本国的地质图,用以描述并解释陆地构造、为已确立的结论保留证据、为学生和其他工作者阐释本国的地质状况及其在经济和工业上的应用。对于整个国家的构造,已经掌握了大量详细的资料,不过还有许多新的工作要做,以便跟上甚至引领地质学思想的发... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 英文
庞大的、并且有些奇怪的爬行动物——恐龙,是中生代的霸主,但它的脑相对来说却很小。例如梁龙,长约80英尺,重达20吨,而脑却仅仅相当于一只大母鸡的蛋那么大。虽然它还有一个较大的起辅助作用的骶骨神经节,主要负责运动并保证其又大又长的身体的整个后半部分的协调;但真正的脑却很小,平均每吨重的身体才只有不到1/4盎司的大脑控制着;由此我们就会明白为什么它们最终失去了统治万物的地位。
英文
在会飞的爬行动物中,脑相对身体的比例有了提高,由爬行类进化而来的鸟类也是如此,前者很可能是因为它们已变为恒温动物;不过,只有在哺乳动物中这一比例才有了明显的增加。尤因他兽是始新世时期一种庞大的像犀牛的动物,体重约两吨,其脑的大小和狗的差不多。每... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | . Temple arrives at an apparent contradiction, starting from principles which he states to be an essential part of quantum theory. From these principles contradictory results follow, as Temple shows by a perfectly rigorous deduction. (The existence of this deduction seems to have been ignored by Fröhlich and Guth.)
中... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | Before applying such an apparatus (assuming, for the sake of argument, that it exists although it probably does not) one would have to make sure, either by experimental investigation or by applying quantum mechanics to its working mechanism, which operator actually is to be associated with it. In other words, an appara... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 鲁道夫·佩尔斯在本文中反驳了乔治·坦普尔最近的一个观点,当时坦普尔显然已经证明了量子力学中存在一个矛盾。坦普尔认为应该有唯一的量子力学算符(量子理论的数学表示)对应于每个经典的运动变量,如位置和动量。佩尔斯对坦普尔的这个结论表示质疑,他指出在量子理论中变量在数学表达式里的次序是很重要的,而在经典理论中是无关紧要的。事实上,海森堡测不准原理就是源于这种所谓的算符的不对易性。
英文
最近,坦普尔教授[1]
、弗勒利希博士和古思博士[2]
都讨论了量子力学的逻辑一致性问题。坦普尔从他所陈述的量子理论的基本原理出发得出了一个明显的矛盾。这些矛盾的结果正是坦普尔从量子力学的基本原理出发通过严密精确的推导得到的。(弗勒利希博士和古思博... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | from the equations of quantum mechanics. But the effect lacked intuitive justification. Here R. A. Newing shows that the zero-point energy can be seen as a consequence of Heisenberg's uncertainty principle, which forbids complete specification of position or momentum. Newing shows that the minimal possible value for th... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 英文
根据量子力学原理,一个振子具有确定的振动零点能,科学工作者也正在试图使用一些基本的原理来对这一结果进行直接地
表述。在简单的谐波场中,考虑到位置、动量和能量之间的特殊关系,我们发现或许可以根据测不准原理推导出零点能。
英文
处于零点能态的振动粒子如果会静止于场的中央,那么它的位置和动量都能准确地确定下来。但是这与测不准原理相矛盾,因此谐振子是不可能处于这种态的。我们可以根据测不准关系∆p
∆q
≥h
/2π计算出能量的最小值。一维谐振子的能量是由下面的能量方程定义的
如果我们这样理解:
q
的大小=∆q
=位置不确定度
p
的大小=∆p
=动量不确定度
于是有
得出
μω∆q
= ±∆p
.... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | , I was led in 1908 to the discovery of magnetic fields in sunspots by a hypothesis based upon the results of two series of studies, begun at the Kenwood Observatory in 1890, and continued at the Yerkes and Mount Wilson Observatories. The first of these related to the nature of various phenomena of the solar atmosphere... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | was quickly found to harmonise with Zeeman's laboratory results on the spectra of vapours. My solar work was greatly facilitated by experiments made in our own laboratory by King, provided with a Du Bois magnet and all the essential equipment.
中文
Magnetic Polarity of Sunspots
The sunspot spectrum contains many thous... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | From such characteristics a scheme of magnetic classification developed, which has been used ever since on Mount Wilson in recording the magnetic phenomena of thousands of spots examined with the 150-foot tower telescope and the 75-foot spectrograph. This long task, in which Nicholson, Ellerman, Joy and many others hav... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | A more detailed examination of the observations, many of which have been published in the Astrophysical Journal
and the Publications of the Astronomical Society of the Pacific
, would suffice to show that occasional exceptional phenomena complicate the explanation of these changes. About ninety-seven percent of consi... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | strips should attain maximum values on the central meridian at about 45° north and south latitude, and decrease to zero at the poles and equator.
中文
In the search for such minute displacements, every precaution was taken to obviate any possible bias on the part of the measurers. Thus the quarter-wave plates were fre... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | Several years ago I renewed this investigation with the coelostat telescope (equivalent focal length 150 feet) and the 75-foot spectrograph of my solar laboratory in Pasadena. Having made a new series of photographs of the same dispersion as those previously taken on Mount Wilson, I endeavoured to measure them by sever... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | Taken altogether, the evidence is overwhelmingly in favour of the existence, polarity and order of magnitude of the general magnetic field of the Sun given in our original papers. There is thus far no evidence of change of polarity at sunspot minima. As for any possible changes of intensity, every single determination ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 我们最新的应用结果包括首次完成的对太阳黑子23年磁周期的观测以及通过对太阳普遍磁场的长期观测得到的结论,这些观测是为了检验始于1912年的对太阳磁场的最初观测,1912年的观测结果曾被人们认为是无可争辩的。
英文
太阳黑子的塞曼效应
正如11年前在《自然》杂志上的[1]
解释一样,1908年,基于之前的两项研究成果,我做了一个假设,并由此发现了太阳黑子的磁场,这两项研究工作均于1890年在肯伍德天文台开始,后来在叶凯士天文台和威尔逊山天文台继续进行。其中第一项工作是关于太阳大气中一些现象的本质的研究,通过使用光谱仪和太阳单色光照相仪,我们对此有了一定的了解。1908年,根据在威尔逊山天文台观测到的H
α
线,人们第一次发现... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 我们在图1中总结了1908~1935年黑子的纬度和磁场极性的变化情况。
英文
图1.太阳黑子磁场极性的规律。这些曲线近似的表示了黑子群平均纬度的变化和相应的磁场极性。这些黑子群是1908年6月至1935年1月在威尔逊山上观测到的。前导黑子出现在右边。
英文
《天体物理学杂志》和《太平洋天文学会会刊》上刊登了大部分关于太阳磁场的观测结果,而对所有的观测结果进行仔细研究后我们可以发现:偶尔出现的小概率现象增加了人们解释此种变化关系的难度。虽然97%的数据都一致明确指向了那些普遍的结论,该结论适用于太阳和其他无数的恒星,但是这种结论仍只是一种如图1所示的经验规律。
英文
太阳的普遍磁场
在探测了太阳黑子中的强磁场后,我... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 在过去的几周内[1935年9月14日,通信日期],兰格博士借助于一种新型的复合仪器又获得了另外两组确凿无误的数据核实了上述结果,这种仪器兼容了测量、记录和计算三种功能,主要由兰格博士自己设计并在我们实验室制成。这台仪器的主要优点在于它的运行速度,它可以在短时间内进行大量的测量,并可以避免产生任何可能的偏差。
英文
综上所述,在我们最初的文章中已经提供了充分确凿的证据来证实太阳普遍磁场的存在,并测得了它的极性和强度量级。即便如此,我们手头上还是没有任何关于磁场极性在太阳黑子极小年会改变的证据。由于我们做出的每一个判断都是基于成千上万次测量的结果,因此它反映的是太阳上很多点的平均值。因此,要彻底弄清太阳上磁场强度的变化还需要更多的... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | to such an interpretation in the case of Drosophila
.
中文
In order to decide the latter question, I undertook an experiment in collaboration with Miss Helene Pogossiants, in which, by using certain rearranged chromosomes, it seemed possible to obtain somewhat more conclusive results than in previous work. Crossing-o... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 他认为可能需要“另外一个更普遍的因子”。但是这个因子是什么还不清楚。
英文
布里奇斯、安德森、马瑟、格申森等人认为,染色体的分离与交换之间有明确的关系。他们的研究已经证实,在减数分裂期间,发生交换的染色体比不发生交换的染色体更经常性地分布于子细胞核之间。然而,出现这种关联的本质原因还不清楚。达林顿认为,一般而言,交换是染色体正常分离的必要条件。另一方面,大多数人的普遍观点以及最近格申森、比德尔、斯特蒂文特、斯通、托马斯关于果蝇相关方面的研究结果却与达林顿的观点相反。
英文
为了解决上文中的最后一个疑问,我和海伦妮小姐共同合作利用某种重排的染色体进行实验,希望可以得到比先前的研究工作更有说服力的结果。我们利用雌性黑腹果蝇来... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | . They maintain that some “other factor” is concerned in their experiments. But these experiments have necessarily made use of hybridity, without which genetical tests are impossible; and the particular kind of hybridity (structural hybridity) they have used is bound to have a complicated effect on disjunction. It is i... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | . They show the danger of arguing from the assumptions involved in an abstracted formal use of the terms “chromosome”, “non-disjunction” and even “crossing-over” by the geneticist. They also show the difficulty the geneticist is faced with in dealing with the highly selected viable progeny of structural hybrids, a diff... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 英文
(韩玲俐 翻译;王晓晨 审稿)
Chemical Detection of Artificial Transmutation of Elements
F. A. Paneth and H. Loleit
Editor's Note
By 1935 the transmutation of chemical elements by radioactivity was well established. Ernest Rutherford showed in 1919 that subatomic particles released in radioactive decay could transform non-rad... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | At present, for various experimental reasons, the best choice for the chemical detection of an artificially-produced element seemed to be helium originating from boron according to the reaction5
5
B10
+0
n
1
=3
Li7
+2
He4
.
中文
In a closed copper vessel we bombarded the methyl ester of boron with neutrons. T... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | We wish to express our sincere thanks to Prof. F. L. Hopwood, director of the Radium Department, St. Bartholomew's Hospital, London, to Prof. S. Russ, director of the Radium Department, Middlesex Hospital, London, and to Prof. Stefan Meyer, director of the Institute for Radium Research in Vienna, for kindly supplying t... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 英文
(王耀杨 翻译;汪长征 审稿)
The Slowing Down of Neutrons by Collisions with Protons
H. von Halban, Jr. and P. Preiswerk
Editor's Note
Fermi had recently shown that neutrons passing through substances containing hydrogen would be slowed by collisions with protons. Here Hans von Halban and Peter Preiswerk explore the process ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | such differences.
中文
Spheres with different radii (5-15cm.) were alternately filled with water (0.11 gm. H/cm.3
), ethyl alcohol (0.10 gm. H/cm.3
), benzene (0.067 gm. H/cm.3
) and a liquid paraffin (0.14 gm. H/cm.3
). In the centre of the sphere a neutron source (radon + beryllium) was placed. The activation of... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | showed that influence of the absorption of the cadmium decreased to a half when the distance between the silver plate and the absorber was increased by 2.5 cm.
中文
Fig. 1 shows that the maximum values of intensity are different for different liquids; these differences cannot be ascribed to the quantities of hydrogen ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 英文
不能确定的是:中子对质子的碰撞截面是否为中子速度的单调函数,或者当中子能量与分子的束缚能可比时,碰撞截面是否呈现不连续性。在后一种情况下,两种含有不同结合形式氢的物质在中子慢化的过程中可能会表现出差异性。我们已经进行了一些实验,结果显示出了这种差异性的存在。
英文
用水(氢含量为0.11 g/cm3
)、乙醇(氢含量为0.10 g/cm3
)、苯(氢含量为0.067 g/cm3
)和液体石蜡(氢含量为0.14 g/cm3
)分别装满半径不同(5~15cm)的球。在球的中央放置着一个中子源(氡+铍),在球的表面安置一个银片并对其辐照5分钟,然后利用银片的放射性测量慢中子的强度。
英文
图1显示了单位立体角中... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | NY theory as to the structure of the molecule of simple native protein must take account of a number of facts, including the following:
(1) The molecules are largely, if not entirely, made up of amino acid residues. They contain —NH—CO linkages, but in general few —NH2
groups not belonging to side chains, and in some ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | groups, in so far as these indicate an open polypeptide, can be made as small as we please, even zero if we so desire. The hexagonal folding of polypeptide chains, open or closed, evidently allows the construction of molecules containing even hundreds of amino acid residues in orderly array, and provides a characterist... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | this fabric is dorsiventral, having a front surface from which the side chains emerge, and a back surface free from side chains. Both front and back carry trios of hydroxyls normal to the surface in alternating hexagonal arrays. Such a layer molecule and its polymers, formed also by the same transformation, can cover a... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | . The single-layer cyclol is a fabric capable of covering a two-dimensional area of any shape and extent; a three-dimensional array can then be built, layer upon layer, the linkage being alternately by means of side chains and hydroxyls. The idea that native proteins consist largely, if not entirely, of cyclised polype... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | the polypeptides may be regarded as partially cyclised since they are cyclised at regular intervals, one out of every three (CO, NH) groups being involved. It is also suggestive in relation to a variety of other facts belonging to organic chemistry, X-ray analysis, enzyme chemistry and cytology. I cite the following:
(... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | , 421 (1935); Amer. J. Diseases of Children
, 47
, 945 (1934).
Gorter and van Ormondt, Biochem. J.
, 29
, 48 (1935).
Schulman and Rideal, Biochem. J.
, 27
, 1581 (1933).
Bernal and Megaw, Proc. Roy. Soc.
, A, 151
, 384 (1935).
Bergmann, J. Biol. Chem.
, 110
, 471 (1935).
Astbury, Cold Spring Harbor Symposia o... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 英文
图1.“六元环醇”分子
英文
图2.“四十二元环醇”分子
英文
图3
英文
正六角形排列的多肽表明存在一个新的三维结构
单元,
,可以用来构建多种类型的三维分子。现在正在对这些新的三维结构进行详细的研究。此刻我们关注的只是几乎在同一平面内形成六边形的单环多肽。这种层状环醇分子结构的厚度为一个氨基酸残基。为天然存在的氨基酸都是左旋型
[4]
,因此这种结构呈背腹性,侧链出现在前表面而不是后表面。前后表面均有三个垂直于六角形表面的相间排列的羟基基团。这样的层状分子及其通过同样的转化方式形成的多聚体能够囊括蛋白质所有可能的形状。这为厚度只有一个氨基酸残基的固态蛋白质膜的结构提供了一些参考。在其最紧凑的... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | A New Fossil Anthropoid Skull from South Africa
R. Broom
Editor's Note
For twelve years after Raymond Dart's discovery in 1924 of the infant Australopithecus
at Taungs, the fossil record of human ancestry in Africa remained silent. Controversy reigned about whether the Taungs “baby” was a genuine intermediate in hum... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | Many European and American men of science considered that Dart had made a mistake, and that if he had had a series of young chimpanzee skulls for comparison he would have recognized that the Taungs ape is only a variety of chimpanzee. When after some years the lower jaw was detached from the upper and the crowns of the... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | Two weeks ago [Dr. Broom's covering letter is dated August 8. —Ed.], when visiting the caves at Sterkfontein near Krugersdorp, Mr. G. W. Barlow, the very understanding manager of the lime works there and on whom I had impressed the importance of keeping his eyes open for a Taungs ape, handed me the brain cast of what a... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | The brain cast is perfect in its anterior two thirds. When complete it probably measured in length about 120 mm. and in breadth about 90 mm.; and the brain capacity was probably about 600 c.c. The skull probably measured from the glabella to the occiput about 145 mm., and the greatest parietal width was probably about ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | . The 2nd molar is exceptionally large. It measures 14.5 mm. in antero-posterior length and is 16 mm. across. It has four large cusps with a well-marked posterior fovea. The 3rd molar has been detached from the bone but it is preserved in perfect condition and unworn. It has three well-developed cusps, but the hypocone... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 这一发现使人们开始接受人类进化过程中存在与猿相像的过渡种。
英文
将近12年前,达特教授宣布,在南非贝专纳兰汤恩的一个石灰岩洞中发现了类人猿化石,当时这一消息震惊了世界。该标本来自于一只非常年幼的猿,它保存有大部分脑模和几乎完美的面部部分。功能性牙齿都是乳齿,尽管第一上臼齿和第一下臼齿都已经破龈而出,但还不能咬合在一起。尽管这只猿非常年幼,但据达特估计,其颅容量超过了500毫升,并认为成年猿的颅容量可能超过700毫升。他相信这具小猿化石既不属于黑猩猩,也不属于大猩猩,可能更接近于一种进化成人类的猿类,实际上就是长久以来一直在寻找的、在整个进化过程中缺失的一环。
英文
许多欧美学者认为达特犯了一个错误,如果他对一系列幼年黑... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 英文
第一臼齿稍大,前后长12毫米,横向长13毫米。这属于典型的森林古猿型——有四个发育良好的齿尖并伴有一个小后嵴和一个明显的后凹。这颗牙齿与雷纳努斯森林古猿的第一臼齿非常相似。第二臼齿特别大,其前后长14.5毫米,横向长16毫米,有四个大的齿尖及一个明显的后凹。第三臼齿已经从上颌骨上脱落下来了,但是保存状况非常好,没有任何磨损。该牙齿有三个发育良好的齿尖,但由于有一个大的凹陷侵入,次尖相对较小。这颗牙前后长13.7毫米,横向为15.5毫米。未磨损的牙冠上布满了大量的褶皱。
英文
整个前臼齿和臼齿齿列长59毫米。
英文
这个新发现的灵长类动物可能与汤恩古猿的亲缘关系非常近,但是我们能进行比较的部位还只有脑模和第一上臼齿... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | , and showed that there is a drop in viscosity below the λ-point by a factor of 3 compared with liquid helium at normal pressure, and by a factor of 8 compared with the value just above the λ-point. In these experiments, however, no check was made to ensure that the motion was laminar, and not turbulent.
中文
The impo... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | The results of the measurements were rather striking. When there were no distance pieces between the disks, and the plates 1 and 2 were brought into contact (by observation of optical fringes, their separation was estimated to be about half a micron), the flow of liquid above the λ-point could be only just detected ove... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | . It is evidently possible that the turbulent motion, inevitably set up in the technical manipulation required in working with the liquid helium II, might on account of the great fluidity, not die out, even in the small capillary tubes in which the thermal conductivity was measured; such turbulence would transport heat... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 英文
如同我们之前提到的那样,我们的实验中显示的异常低的黏度,可能确实可以用来解释高热导率,以及由艾伦、佩尔斯和乌丁[2]
所观测到的其他异常性质。在对液氦II进行所需的技术操作过程中,由于其具有较大的流动性,因此湍流的出现显然是无法避免的,即便在用于测量热导率的小毛细管中;而这种湍流运动将通过对流效率极高地传输热。
英文
(王耀杨 翻译;于渌 审稿)
Flow of Liquid Helium II
J. F. Allen and A. D. Misener
Editor's Note
In Cambridge, physicists John Allen and Don Misener had come to t... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | so that the level of liquid helium in the reservoir was a centimetre or so above or below that of the surrounding liquid helium bath. The rate of change of level in the reservoir was then determined from the cathetometer eye-piece scale and a stopwatch; measurements were made until the levels became coincident. The dat... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | The observed type of flow, however, in which the velocity becomes almost independent of pressure, most certainly cannot be treated as laminar or even as ordinary turbulent flow. Consequently any known formula cannot, from our data, give a value of the “viscosity” which would have much meaning. It may be possible that t... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 附表中数据显示了流经毛细管时的速度和相应的毛细管两端的压力差,对它们分别取对数绘于图中。
英文
英文
从上表明显可以看出:
(a
)当压位差p
大幅度改变时,流动速度q
的变化不大。对于较细的毛细管,二者之间的关系近似为p
∝q
6
,但是在速度最低的时候,幂次似乎更高。
(b
)对于给定的压位差和温度,当横截面面积以103
数量级变化时,流动速度只发生微小的改变。
(c
)对于给定的压位差和确定的横截面,在温度从1.07 K变化到2.17 K的过程中,流动速度变化了10倍左右。
(d
)在较粗的毛细管中,对于略高的流动速度,压力-速度之间的关系近似为p
∝q
3
,其中q
的幂次随速度增加而降... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | places. He remarks that a body-centred cubic lattice may be considered as consisting of two shifted diamond lattices, and he assumes that below the λ-point the helium atoms prefer the places of one of the two diamond lattices. The transition is treated on the lines of the Bragg-Williams-Bethe theory as a phase transiti... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | the proper diamond lattice points, and this would signify that we have a body-centred lattice of 2n
places for n
atoms, every place being occupied with the probability
only—even at the absolute zero. In this configuration every atom has on the average four nearest neighbours at a distance of 3.08 A, as in the diamo... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | * being of the order of magnitude of the mass of the atoms. But in the present case we are obliged to apply Bose-Einstein statistics instead of Fermi statistics.
中文
(3) In his well-known papers, Einstein has already discussed a peculiar condensation phenomenon of the “Bose-Einstein” gas; but in the course of time th... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | According to our conception the quantum states of liquid helium would have to correspond, so to speak, to both the states of the electrons and to the Debye vibrational states of the lattice in the theory of metals. It would, of course, be necessary to incorporate this feature into the theory before it can be expected t... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 英文
在本文中我们不可能给出完整的数值计算过程;但是,通过对这种能量的讨论可以阐明,液体He II任何规则结构的静态空间分布模型肯定都是不可能的。这点在计算He巨大的零点振幅时就已被提出[4]
。然而,确定最近邻和次近邻的最佳配位数却有着清楚的物理意义,其可以看作是粗略的哈特里计算,由此我们可得到自洽场和相对应的处于能量极小值的原子的分布几率。
英文
(2)因此似乎可以构造这样一个模型,其中每个He原子在其他原子形成的自洽周期场中运动。用本征函数来描述原子不同的态,类似于在布洛赫的金属理论中用电子本征函数描述电子态;而且,类似于布洛赫理论,最低态的能量可以粗略地表示为波矢K
的二次函数,
其中有效质量m
*与原子质量... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | URING the systematic search for fossil man in Java, one of us (G. H. R. von K.) discovered, in 1937, in the Trinil formation of Sangiren (Central Java), an almost complete brain case of Pithecanthropus
1
.
中文
Amongst the material recently collected ( July 1938) from the same area, a large fragment of an additional ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | According to the state of the sutures, the new skull belongs to a juvenile individual, in spite of the fact that the parietal bones show a thickness of more than 10 mm. near the bregma, and that the temporal line is well developed. The region of the occipital torus is preserved only to a very small extent, revealing on... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 英文
(刘皓芳 翻译;刘武 审稿)
Mesotron (Intermediate Particle) as a Name for the New Particles of Intermediate Mass
C. D. Anderson and S. H. Neddermeyer
Editor's Note
In 1936, Carl Anderson and Seth Neddermeyer at the California Institute of Technology found evidence in cosmic-ray experiments for a particle having mass interme... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | or not, is greater than that of an electron and less than that of a proton. One must consider then three types of particles all carrying electric charges of equal magnitude: electrons, the new particles and protons. We should like to suggest therefore the word “mesotron” (intermediate particle) as a name for the new pa... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | fanciful theory seem all the more perverse. Notable here is his admission that the cyclol theory did not follow from the crucial X-ray crystallographic data on proteins collected by Dorothy Crowfoot and J. Desmond Bernal; and indeed, Bernal is recorded as a sceptical voice at the end of Langmuir's talk.
中文
D
ESPITE... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | One cage in particular contains 288 amino-acid residues, which is equal to the number determined by physico-chemical methods in the case of egg albumin, within the limits of accuracy of these methods. In this particular case, the cage is a truncated tetrahedron which does not differ greatly from an octahedron.
中文
No... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | Dr. Langmuir stressed the point that the X-ray data, like many of the other facts explained by the theory, such as the appearance of α- but no β-amino acids, were not used as data in constructing it originally; nevertheless, the results of the X-ray investigation, in Dr. Langmuir's view, confirm many features of the st... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 这样其分子量(事实上是它们的比率)离散分布以及其分子近似球形就都有了很自然的解释。
英文
特别是有一种笼状结构包含288个氨基酸残基,这与通过物理化学方法测定的卵清蛋白中氨基酸残基的数目是一致的,这些结果是在这些方法的精度范围内测定的。在此情况下,笼状结构是一个截顶四面体,和八面体没有太大的差别。
英文
现在,可以通过各种温和的处理方法(振荡3~4分钟,在某些情况下65°C加热1~2分钟足矣)使蛋白质变性,进而使其表现出与天然蛋白质截然不同的性质,但其分子量不发生改变。这表明这些变性的蛋白质实际上是由化学家已经发现的那些多肽链组成的,因为研究中必须用到的处理足以引起这些变化。综合考虑适用于天然蛋白质的“环醇”假说,蛋白质... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | , makes it of interest to consider the nature of the cyclol bond, upon the postulation of which this structure and the cyclol theory of protein structure in general4
depend. The making and breaking of a cyclol bond between an NH group of a polypeptide chain and a CO group of the same or of another polypeptide chain re... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | (5) They spontaneously form monolayers of extreme insolubility.
(6) They exhibit a high degree of specificity in biological reactions.
中文
It has already been shown that the cyclol hypothesis explains (1), (2), (4). With regard to (3) and (5), we may point out that the extreme insolubility of the monolayer formed fro... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | , and it may be presumed that one and the same structure will under standard conditions break down in a unique way. Further, if preferential paths of breaking cyclol bonds be postulated, preferential paths of making cyclol bonds must also be postulated. Experiments have recently been reported purporting to disprove the... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | From the point of view of biology, cytology and immuno-chemistry, however, the most striking characteristic of the globular protein is its high degree of specificity. This, we suggest, indicates an organized structure with its own characteristic modes of vibration, which depend on the nature and arrangement of the vari... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | . Such a close distance of approach is evidence of considerable mutual energy of oxygen atoms, which can only be due to the presence of hydrogen between them12
. For certain compounds, for example, salicylaldehyde and o
-nitrophenol, the presence of intramolecular hydrogen bonds has been confirmed spectroscopically b... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | its sets of rings within rings and its multiple paths of linkage between atoms (cf. Fig. 2) should be capable of just such a type of resonance.
中文
May we not perhaps regard each diazine ring in the cyclol fabric as the analogue of an electrical resonant circuit, the natural frequency of which is determined by the ch... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | The work on protein monolayers indicates that only weak forces are required to open cyclol bonds. We are of the opinion that many chemical techniques are sufficient to rip open the cyclol fabric into polypeptide chains, so that the chemist by his very operations may destroy the structure he seeks to study. On this view... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | Little or nothing is known at present as to the path or the nature of protein synthesis. We see no reason to suppose that a cyclol fabric forms spontaneously from polypeptide chains. If on occasion such cross linking occurs, this is probably a relatively unstable state. The non-formation of cyclol bonds between simple ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | , 2005 (1938).
Wrinch and Langmuir, J. Amer. Chem. Soc.
, 60
, 2247 (1938).
Wrinch, Science
, 85
, 566 (1937); Trans. Far. Soc.,
33
, 1368 (1937).
Wrinch, Nature
, 137
, 411 (1936) et seq
.
Corey, J. Amer. Chem. Soc.
, 60
, 1598 (1938).
Langmuir and Schaefer, J. Amer. Chem. Soc.
, 60
, 1351 (1938).
Langmuir... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 其中有一类对于理解生命物质最为重要,那就是具有结晶态的球蛋白,例如胰蛋白酶、胃蛋白酶等。这些物质在许多方面已有了详尽的定义,而环醇理论所关注的正是这一类蛋白质。
英文
下面列出的是这些物质已被确认的某些性质:
(1)它们具有呈离散分布的确定的分子量。
(2)它们包含一定数量的各种特定氨基酸残基,其数量往往成百上千。
(3)它们可溶于水或者盐溶液中,但pH的变化会影响其溶解性。
(4)它们会在很微弱的刺激下发生变性。
(5)它们可以自发地形成极难溶的单分子层。
(6)它们在生物反应中表现出高度的特异性。
英文
以前已经证明,环醇假说可以解释(1)、(2)和(4)。至于(3)和(5),我们可以指出,可溶性蛋白质形成的单分子层... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 在上述实例中,氧–氧原子间距约为2.5Å,明显短于氧离子O2–
半径的两倍即2.7Å,比起中性氧原子的半径就更是短很多。在环醇结构中,每一个三嗪环中的三个碳原子上都有一个羟基,间距为
,如果长度α
的数值介于C–C与C–N间距之间(到目前为止人们都是这么处理的)即1.5Å的话,那么该间距等于2.45Å。
英文
蛋白质最不同寻常的性质之一就是其在生物反应中的特异性。每一种不同类型的动物体内,其血红蛋白似乎都具有不同的光谱,并且在与氧发生作用的细节上有所不同。由此必然会推出,蛋白质分子的某些特征可以将某些效应传递到分子中的其他部分,特别是传递给辅基。这种化学效应的传递现象,虽然在某种程度上也可以在诸如固醇类化合物中被观测到,... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 英文
我们还应当把注意力转向可以预期的稳定性差异:如一个环醇键在多肽链内或多肽链间形成时的稳定性差异,三个环醇键形成一个三嗪环时的稳定性差异,以及可以料想到的存在于一块环醇结构与一个完整环醇多面体之间的更为惊人的差异。毫无疑问,与不完全的环醇结构相比,许多因素对完整的多面体结构的形成更为有利。这些因素也许可以解释环醇笼的存在,即便分离的环醇键也可能具有内在的不稳定性。
英文
(王耀杨 翻译;顾孝诚 审稿)
New Broadcasting System
Editor's Note
An engineer in the United States, Nature
reports here, has developed ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | use with modern valves and circuit arrangements. Among the advantages claimed for the new system are that it effects a considerable reduction of interference in radio reception, and that a much larger number of broadcasting channels will become available in any given wave-length band. Against these, however, is the ser... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 英文
(刘霞 翻译;赵见高 审稿)
The Expanding Universe and the Origin of the Great Nebulae
*
J. H. Jeans
Editor's Note
The astronomer James Jeans here criticises recent speculations of George Gamow and Edward Teller on the origins of galaxies. Gamow and Teller started from an estimate of the mass density of the universe, and re... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | Recent investigations by Sinclair-Smith, Holmberg and others suggest that Hubble's estimate of 10–30
for mean density (which was anyhow only given as a lower limit), is emphatically on the low side. The average nebula appears to have a mass of at least 1011
Suns. This gives a mean density, for nebular matter alone, o... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | J. H. Jeans: Cleveland Lodge, Dorking.
References:
Nature
, 143
, 116 (1939).
Hubble, “The Realm of the Nebulae”, 189.
Loc. cit
., 178.
“Astronomy and Cosmogony” (second edit.), 348.
*
Translator's Note: “The Great Nebulae” in this paper refers to galaxies, which are different from the modern notion of nebulae ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | Glaciological Results of the Jungfraujoch Research Party
T. P. Hughes et al.
Editor's Note
Max Perutz became one of the outstanding X-ray crystallographers of the period after the Second World War and won a Nobel Prize in 1962. In 1939, however, he had fled from his native Austria to avoid persecution by the German g... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | passing from early firn to glacier ice was found to be a gradual one. However, a transition point between the two could be distinguished at a density of about 0.84, since here the hitherto porous firn becomes impermeable to water by the freezing out of descending melt water and by a slow process of settling. Measuremen... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | ) ice bands, which are also of sedimentary origin; the crystal orientation of these is similar to that of pond ice. Other types of bands are to be seen in glacier tongues; of these the most important are the “blue bands” which are of tectonic origin. Bands of sedimentary origin are also found in the glacier tongues.
(5... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 不过,可以认为密度值约为0.84时是两者之间的转折点,因为从这点开始,由于融水的减少以及缓慢的沉降作用,之前多孔渗水的粒雪变得无法使水透过。观测显示沉降作用是使其密度增大的一个重要因素。
(2)粒雪的温度。
利用埋在冰面以下30米处的热电偶,我们发现冬季寒潮可以穿透到冰面以下15米处。而在该深度以下,整个冰川则处于压力融化温度。在夏季,粒雪的升温主要是由融水从地表向下渗透所致,而且我们发现,其温度升高的速度取决于粒雪的结构及其渗水性。
(3)结晶学研究。
用晶体光学的标准方法,我们对采自冰川内部样本切割来的薄片中晶体的大小、形状和定向方位,以及孔隙的分布进行了研究。我们对切片中大量晶体定向方位的统计学研究,证明了是否存在优选定向... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | that the experimental distribution curves did not agree in shape with this prediction in the sense that the number of electrons of low energy (relative to the upper limit of the spectrum) was considerably greater in the experimental than in the theoretical curves. A modified theory was then proposed by Konopinski and U... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | We therefore investigated the view that the original theory of Fermi correctly represents the elementary law; but that the observed spectra, in so far as they belong to “allowed” transitions, do not represent the effect of a single nuclear transformation, but rather a superposition of different spectra belonging to tra... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | F was reported by Burcham and Smith11
, and measurements of the energy of this radiation, which are being made by Bower12
, indicate a value of about 2.2 Mv. Although γ-radiations of the predicted energies from the other elements of our table have not been reported, it is interesting to notice that an energy level in... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 恩里科·费米最近提出了放射性β衰变理论。正如汉斯·贝特和他的同事在这里所指出的,该理论的预言与实验结果不符,例如,预言认为几乎没有出现低能电子。另一种理论虽能解决这个难题,但却引入了其他问题。本文作者给出的解答是,不妨假定费米理论是正确的,只是迄今为止的实验还没有观测到简单的放射性衰变过程,而观测到的是混在一起的导致不同核状态的衰变过程。如果仔细检查β衰变中放出的γ射线,或许可以发现支持这一观点的证据。
英文
费米最初的β衰变理论[1]
明确地预言了从β放射性元素发射出的电子的能量分布。但是,人们发现[2]
实验中能量分布曲线的形状与费米理论的预言不一致:在能量分布实验曲线中,低能电子(相对于能谱上限来说)的数目明显多于理... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | 英文
(王静 翻译;厉光烈 审稿)
Liquid Helium
J. F. Allen and H. Jones
Editor's Note
One of the sensations of the late 1930s was the discovery of the strange properties of liquid helium II—a form of liquid helium that appears when the ordinary material is cooled below 2.19K. The Royal Society Mond Laboratory was established in t... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0302. 《自然》百年科学经典（第三卷）(英汉对照版)(1934-1945).epub | .epub | 24,505,760 | 2025-09-26T19:07:02.019948 | confine our attention largely to the interesting newly discovered transport effects, and give an account of recent experiments the results of which at present seem to find general acceptance.
中文
Equilibrium Properties of Liquid Helium
Helium at atmospheric pressure liquefies at 4.22°K.; the critical temperature is 5... | 400套付费套装书 |
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