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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 | W. Newton (solar phenomena and terrestrial magnetism), Dr. A. D. Thackeray (solar phenomena), Prof. L. Vegard (auroral phenomena and the physics of the upper atmosphere), Prof. W. M. H. Greaves (the 27-day recurrence tendency of magnetic storms) and Prof. F. J. M. Stratton (general summary).
日地关系
*
编者按
战争的爆发使英国科学促进会... | 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
根据一个已知多年的事实可以说明太阳黑子和地磁场之间存在更进一步的关系,即磁暴现象往往发生在一个太阳自转朔望月(大约27天)的时间间隔内。根据1874~1927年格林尼治对403次磁暴的记录,人们已经对此关系进行了详细的研究。磁暴根据强烈程度不同可分为5组,其划分标准是地磁三分量D
、H
和V
的平均值。通常的情况是每个磁暴后都会有几天磁暴日,且只有强度较小的磁暴(小于180γ)才有27天周期性出现的趋势;在一些更小的磁暴(小于150γ)中,这种周期需要54天。
英文
这个结果可以用另一种方式来表述:如果仅关注27天周期性出现的磁暴,会发现随着磁暴从微弱到剧烈的变化过程,“连续磁暴”在所有磁暴中所占的比率会从0.2... | 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 | 最后,斯托末近来观测得到的“日耀极光”光谱似乎预示了对大气最高层区域的研究具有广阔的前景,而这一区域也正是太阳辐射最初冲击到地球的大气部分。
英文
(刘霞 翻译;孟庆任 审稿)
*
关于日地关系的讨论原本定于9月5号作为科学促进会A分会(数学物理分会)的主题在邓迪进行。由于国际形势的原因,该会没能举行,于是下面的报道包括了来自不同人士关于这一主题各个方面的内容:阿普尔顿博士的无线电效应,牛顿先生的太阳现象和地磁场,撒克里博士的太阳现象,韦加德教授的极光现象和高层大气物理,格里夫斯教授的磁暴27天的重现性和斯特拉顿教授最后的概括总结。
Gene and Chromosome Theory
*
H. J. Muller
... | 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 | Regarding the mechanism whereby structural changes in chromosomes come about, a series of experiments by the present author and co-workers was reported, substantiating and extending, for Drosophila, the earlier conclusions of Stadler, of McClintock and of Sax on plant material, and of Muller and Belgovsky on Drosophila... | 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 | lying near to them in the chromonema, by a kind of “position effect” (Schultz, Prokofyeva, Panshin, Khvostova), and the important new point was brought out that the variations in staining—which, as proved by Caspersson and Schultz's studies of ultra-violet absorption spectra, fairly represent nucleic acid distribution—... | 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 | possible to estimate the “sensitive volume” for a gene mutation, that is, the amount of contiguous space occupied by material so constituted that one ionization, occurring anywhere within it, is capable of producing some one or more of a given series of alleles. Similar work, utilizing the frequency of chromosome break... | 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 series of papers dealing with the production of mutations by ultra-violet light showed the notable progress made in this field since the last congress. It was shown by Stadler that the curve representing the effectiveness of different wave-lengths in producing gene mutations and deficiencies in maize pollen begins ... | 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 result, which was corroborated for Drosophila sperm by experiments carried out by Muller and Mackenzie, gives some ground for supposing that ultra-violet does not act by breaking the chromosomes, and that therefore gene mutations may not consist merely of linear rearrangements of ultra-small size, involving “intra... | 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 | reported by Astbury that the nucleic acid spacings are of the same magnitude as those within the protein (polypeptide) chain, a feature which would allow the nucleic acid to unite in parallel with the protein and so perhaps to serve as an intermediary in its synthesis. The paper of Mazia also was of interest in this co... | 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 | 中文
A series of special conferences were held on problems of the gene, presided over chiefly by J. B. S. Haldane. These were very well attended. At these “gene conferences” many of the reports of those unable to attend were read, and many of the above and related questions concerning gene and virus structure and gene m... | 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 | 因而有人提出下面这一重要的新观点,着色的变化与基因活性的变化彼此关联——这已被卡斯帕森和舒尔茨通过紫外吸收光谱研究证明。紫外吸收光谱可以清楚地反映出核酸的分布。普罗科夫耶娃和考夫曼还发现,具有某种程度异染色质性的小间隙区域相当广泛地分散于染色质中并且经常与那些显然是新生成的重复段区域相一致(这意味着基因可以通过裂解方式而表现出异染色质性)。
英文
在大量实验的基础上,提墨菲夫–莱索夫斯基对基因突变的机制进行了分析并提出其起因:(1)通过孤立的原子活化作用,它们显然是来自于热动能的突然增值;(2)通过来自于辐射的单一电离化作用。拉伊·周赫利发现,在单一离子水平,即使是强度低达0.01 r/min(比以前进行的这类研究中所用的最低... | 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
阿斯特伯里就其本人的研究和另外一些关于病毒及其他蛋白质化学结构的现代研究进行了精彩的描述,并对那些可能会有助于解释基因的可突变自我复制的特征给予了特别的考虑。他,还有卡斯帕森和舒尔茨(他们报道了处于生长期时染色体和细胞质中核酸的增加),将注意力集中于核酸在这一过程中担当的角色。阿斯特伯里报道的一个重要事实是核酸间隔与蛋白质(多肽)链内的间隔具有同等的数量级,此特点将核酸和蛋白质联系起来,因此有可能在其合成过程中充当媒介。就此而言梅齐亚的论文也是值得注意的,因为该论文指出用胃蛋白酶或核酸酶消化并不能使唾液染色体的骨架分解,但用胰酶消化则能使其分解;因此它可能是由精蛋白或组蛋白链构成的,以核酸交叉连接以外的某种方式横向连接在一起... | 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 | NE of the most active branches of genetics at the present time is the study of the ways in which genes affect developmental processes, and the section devoted to physiological genetics had a full and interesting programme. The problem of genic action is so complex and many sided that very many different methods of appr... | 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 | development of Drosophila.
中文
Several reports dealt with gene effects on processes which are chemically more or less defined. Thus we had further chapters in the important and rapidly developing researches of Price, Lawrence and others on flower pigments, and Beadle, Ephrussi and others on Drosophila eye colours. Pe... | 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 | of a heterochromatic character and finally apparent disappearance. It is suggested that the appearance of excess nucleic acid is correlated with an inactivation of the gene as a developmental agent. The nucleic acid metabolism can be followed somewhat further, since it is found that the presence of extra heterochromati... | 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 | 在这个领域中最重要的新发现可能是休厄尔·赖特对豚鼠皮毛颜色的新研究,数年前他就进行过初步的实验。现在他已经能够给出已知的为数众多的基因之间关系的结构图,并且提出它们之间定量关系的数学理论。
英文
针对相同的问题,舒尔茨和卡斯帕森提出了一种截然不同的研究途径,他们通过研究染色体本身获得了一些数据,这些数据引发了人们对受基因直接影响而发生的化学改变的思考。由于其在中紫外区有强烈的吸收,卡斯帕森提出用分光光度计法检测活细胞内核苷酸类物质的分布和变化。他们发现,在细胞核中核酸对于染色体的发育似乎是必不可少的,而且它们主要是在染色体分离之前的最早期合成的。舒尔茨对果蝇中富含核酸的染色体上异染色质区域的一部分转移到正常常染色质区域的易位现... | 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 | (September 1939). These articles summarize the results of several technical papers published on this subject during the past few years. It seems likely that the Crab Nebula was first recorded by John Bevis, an English physician, in 1731. It was rediscovered in 1758 by the French astronomer, Charles Messier, and was lat... | 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 of Jupiter. By combining the apparent linear expansion in seconds of arc per annum with the absolute expansion in km./sec., the order of distance was derived as 1,500 parsecs, equivalent to nearly 5,000 light years. Using this distance and the apparent magnitude of Jupiter (–2.2 m.), the absolute magnitude of –13.... | 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 | 同时,伦德马克指出,中国和日本的史书中记载,公元1054年曾观测到持续了6个月(编者注:北宋至和元年)的特亮的客星(超新星),其位置与蟹伏星云的位置相近。1934年,伊巴翻译了日本古书中的相关记录,发现这一天体的位置靠近金牛座ζ星,其亮度相当于木星的亮度。综合上面已经得到蟹状星云的视膨胀角速度(单位:角秒/年)和绝对膨胀线速度(单位:千米/秒),我们可以计算出蟹状星云与地球的距离为1,500秒差距,约等于5,000光年。利用这一距离和木星的视星等(–2.2等),我们可以得到这颗新星的绝对星等为–13.1,该亮度至少是普通新星的100倍。
英文
在第600期的《威尔逊山天文台研究通讯》上,巴德根据收集到的观测数据将新星分为两类:... | 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 | Pithecanthropus material before definitely solving this problem.
中文
These discoveries materialized. Following the recovery of a rather primitive infantile skull (Homo modjokertensis
) in 1936 and of a lower jaw of an adult individual, one of us (G. H. R. von K.), during 1937, discovered a skull in the undoubted Tri... | 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 | (2) Mandible of Kedung Brubus (Dubois, 1891): Pithecanthropus mandible A.
(3) Juvenile skull of Homo modjokertensis
(Geol. Survey 1936)
*
.
(4) Mandible of Sangiran (v. Koenigswald, 1936): Pithecanthropus mandible B.
(5) Skull of Sangiran (v. Koenigswald, 1937): Pithecanthropus skull II.
(6) Skull fragment of Sangir... | 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 main differences so far as the skull cap is concerned consist in that in Pithecanthropus (skulls I and II) the supraorbital tori pass directly over to the extraordinarily flattened forehead, whereas in Sinanthropus the supraorbital ridges are much more demarcated from the tuber-like vaulted but otherwise also stron... | 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 differences in size and proportions of the upper and lower jaws of both Pithecanthropus and Sinanthropus, apparently chiefly due to sexual differences, also serve as a criterion of the cranial conditions in this respect. The lower and upper jaws from Sangiran are much too large for the small Pithecanthropus skulls ... | 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 longest of all three. In addition, it is evident that—the first example of a fossil Hominid known hitherto—the upper canines of both sides are separated from the lateral incisors by a broad diastema, the width of which amounts to 6.2 mm. on the right side (d
, in reproductions a
and c
). This width comes close 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 | Pithecanthropus and Sinanthropus undoubtedly represent the most primitive Hominid forms known hitherto, which, according to Boule, may be ranged collectively under the name Prehominids. Which of the two types must be taken as the more primitive cannot be decided with absolute certainty for the present. Fragments of Sin... | 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 finds reported herein show that Java has become the most important centre for the study of Prehominid forms. Not only Prehominids, but also the following evolutionary stage, Homo soloensis
, are represented there. Furthermore, we know that the Wadjak man of Java represents another early form of recent man, whose 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 | the more primitive of the two. If these conclusions are accepted (as they certainly should be) it now becomes necessary finally to discard the generic term Sinanthropus. The Chinese fossils should logically be referred to the species Pithecanthropus erectus
, or, if it should be thought more desirable as a temporary c... | 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 | ., 73
, 31 (1938-1939).
*
On the basis of my study of the original, I have now come to the conclusion that this infantile skull really represents a Pithecanthropus child. I shall report on this elsewhere.—F. W.
爪哇猿人与中国猿人的关系
编者按
1931年,戴维森·布莱克(步达生)在发现“北京人”(中国猿人)后不久,又对中国猿人与在爪哇发现的爪哇猿人之间的相似性进行了探讨,这项工作似乎是自然而然顺理成章的。当时爪哇... | 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
头盖骨的主要差别在于:爪哇猿人(头骨I和II)的眶上圆枕直接过渡到非常扁平的前额,而中国猿人的眶上脊(眉脊)与拱状隆起且同样呈低平状的前额之间的界限更为明显。另一方面,中国猿人的顶孔区扁平,而爪哇猿人的顶孔区圆隆。最大的相似性在于颞骨和枕骨的一般形式和结构,而且这些骨头的某些特别的细节也完全相似。爪哇猿人III号头骨碎片与中国猿人头骨E呈现出完全相似的特征,即便在一些非重要的结构上也是如此。除首次提到的矢状脊外,在矢状缝每一边的顶孔点区都有一条短沟,步达生在中国猿人头骨E中对此作了描述与图示。
英文
凯登·布鲁伯斯发现的下颌骨因其宽阔的二腹肌窝位置靠近底部——这是唯一可用的判断标准——被视为爪哇猿人的代表。在大小和比例... | 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 | 那些象征着相对进步的特征,如较大的颅容量以及其他一些结构特征,可能是直接从爪哇猿人演化而来,并且与梭罗人已达到的尼安德特人阶段的情况相符合。现有的两件梭罗人胫骨碎片除呈现明显的扁平外,在一般形状和细节上没有显示出特别现代人类的特点。
英文
在这里所报道的发现表明,爪哇已经成为最重要的研究前人类型的中心。因为那里不仅有被归为前人的爪哇猿人,还有作为其后续进化阶段的梭罗人。此外,我们还知道爪哇的瓦贾克代表着现代人类的另一种早期类型,其上颌(瓦贾克II)在某些方面与爪哇猿人的上颌惊人地相似。
英文
最后,我们对荷属东印度群岛政府的官员和华盛顿卡内基研究院表示感谢,感谢他们慷慨的支持,他们的支持不仅使得近期在爪哇当地的研究得以进... | 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 | time is still debated.
中文
M
E. J. Gheury de Bray suggests1
that measurements of the velocity of light show that it is changing according to a formula:
c
= 299,900 – 3.855 T
, (1)
T
being measured in years from 1900.
中文
Assuming that Planck's constant and the energy E
given out by an excited atom remain un... | 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 | , Great Britain has only to her credit a conspicuous failure. Is there in this country no one who can redeem it from this position and settle this question, which lies at the basis of physical science, considered in its broadest aspect?
中文
Two observations, of Newcomb (1882.7:299,860) and of Michelson (1882.8:299,85... | 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 | 谷瑞·德布雷
英文
(王耀杨 翻译;张元仲 审稿)
The Evolution of the Stars
F. Hoyle and R. A. Lyttleton
Editor's Note
Astronomers Fred Hoyle and Raymond Lyttleton review how recent advances in nuclear theory were fundamentally changing astronomers' understanding of stellar evolution. It was now possible, as George Gamow had recently ... | 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 | new developments practically solve the problems of stellar evolution. This seems to us to be so far from being the case that some further discussion of the claims of nuclear theory as the main factor in stellar evolution would be desirable.
中文
In the first place, it should be noticed that the application of nuclear ... | 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 | Now if all the stars could be regarded as single autonomous bodies, it would be difficult to dispute the validity of these views by direct means. But it so happens that the frequent occurrence of binary systems enables a simple test of the theory to be made, for in the case of binary stars both components must be of co... | 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 | . Thus the existence of spectroscopic binary systems in which one component is a red giant or any highly luminous star presents an immediate contradiction of the theory given by Gamow. Moreover, there seems to be a general tendency for the mass of binary systems to increase with decreasing separation.
中文
While on 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 | However, quite apart from the foregoing objections to the constructive portion of Gamow's article, it is very noticeable that no reference is made to the wide class of dynamical features that is associated with the stars. This, of course, is the direct result of attending only to the internal physical properties 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 | . Moreover, the two short-period groups exhibit a most remarkable property in that none of them, out of more than two hundred available examples, possesses a close companion, whereas about one star in five of normal stars of similar spectral classes does possess a close companion. On the other hand, long-period variabl... | 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 | 如乔治·伽莫夫近期所指出的,现在有可能证明核化学在恒星当时的密度和温度下是有重要作用的。伽莫夫认为恒星演化的大多数问题现在都已经解决了,但霍伊尔和利特尔顿对此并不认同。例如,伽莫夫认为所有红巨星一定是在新近才产生的,但这似乎是最不可能的事情。霍伊尔和利特尔顿是对的:那时的大多数物理学家只知道核化学方面的初级知识,但对核聚变这一驱动恒星活动和演化的关键过程却一无所知。
英文
乔治·伽莫夫教授最近在《自然》[1]
杂志上讨论了核物理理论的最新进展在恒星演化问题上所取得的结果。根据现有可用大量核反应得到的准确知识,人们有可能确定在恒星当时密度和温度下哪些过程具有重要的作用,并且在此基础上,人们得到了对亚原子能量释放率的可靠估计。这... | 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 | 这样看来,似乎无论我们从什么角度来处理双星系统观测性质上的问题,这个已被天文学家意识到的矛盾总会以某种形式存在。
英文
然而,除了前面对伽莫夫文章理论构建部分提出的异议外,很明显,还没有文献提到与恒星相关的广泛动力学特征。当然,这是只关注恒星内部物理性质的直接结果;但是,总的来说我们考虑的动力学性质是个很重要的问题,为此任何一个理论要令人信服都应该对此给出说明。于是,诸如单个恒星、双星以及聚星系统的形成,双星质量普遍随间距的减小而增加,以及观测到类似在恒星之间近似均分能量,类似这样的问题似乎是所有恒星演化理论的真正关键。一个恒星内部结构的理论不能解释本动速度和光谱类型之间的关系,也不能解释为什么观测到的大质量恒星都倾向位于银道... | 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 | N this letter, a brief account is given of the preliminary results of an investigation of the radioactive gases evolved in the fission of uranium nuclei. This investigation was commenced this summer but was interrupted by the outbreak of the War. Even if the results so far obtained are not more complete than those obta... | 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 shorter periods were estimated from a decay curve obtained in a separate experiment, in which the flow of gas was stopped at the same time that the source was removed, and the records of the two counters at any subsequent time simply added. This gave two periods of about 30 sec. and 4 min., the ratio between the ra... | 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 | , for the two counters measured 12 min. after the beginning of the irradiation for four capillary tubes corresponding to values of the time lag τ2
–τ1
between the counters stated in the first column.
中文
中文
The agreement between the experimental and calculated values for the ratio G
1
: G
2
is seen to be very ... | 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 | 这一时间间隔对于完全建立平衡来说不是很充足,不过从另一方面来说,它与长寿命衰变产物的周期相比却已足够短,这足以确定所获得的值在任何可观程度上都不依赖于这些产物的形成。
英文
假设放射性气体仅由衰变常数分别为λ1
和λ2
、生成速率分别为每秒n
1
和n
2
个原子的两种短周期成分组成,其任一台计数器中的计数率都可以很容易由下列式子给出:
式中,τ表示循环气体从盛铀容器到达我们正在讨论的计数器所需的时间,θ表示气体流过计数器所需的时间,T
表示整个循环过程的周期。
英文
下面的表格中记录了两台计数器的计数率G
1
和 G
2
,其中,G
1
和 G
2
是在辐照开始12 分钟后,两台计数器对相应于表中第... | 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 | is the mass of the proton, and no increase with energy for ε>μc
2
. The experiments by J. G. Wilson3
have shown that the scattering cross-section even for an energy so low as a few times μc
2
(108
ev.) is smaller than (1) by an order of magnitude and does not increase with energy.
中文
As can be seen from the comp... | 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 | , (2) is smaller by a factor (ΔM
/μ)2
than (1). A value ΔM
/μ of approximately 1/5 would be sufficient to bring (2) into harmony with the experimental requirements. For ε greater than Mc
2
, φ will probably decrease owing to the relativistic features of the proton.
中文
Similar considerations must be applied to 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 | proton. The anomalous magnetic moment of the proton then becomes (in units of the nuclear magneton μ0
)
This is of the right order of magnitude when ΔM
/μ is approximately 1/5, which is the value assumed above.
中文
(145
, 29-30; 1940)
W. Heitler: H. H. Wills Physical Laboratory, University, Bristol, 8, Nov. 28.
... | 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 | 那么,这些粒子将会极其不稳定,并且在重核结构中不会起任何作用。用ΔM
表示新粒子与质子之间的质量差,当能量满足ε<Mc
2
时,假定
,纵向介子的散射截面可以表示为:
然而当能量满足ε>μc
2
时,这个表达式的值不会
随能量增加。如果p
趋近于μc
2
,表达式(2)比表达式(1)小 (ΔM
/μ)2
倍。一个趋于1/5的ΔM
/μ值,足以使表达式(2)与实验要求相吻合。如果能量ε大于Mc
2
,φ可能会因为质子的相对论特征而减小。
英文
对于自旋问题必须采取相似的分析思路。自旋同样会对高散射截面(对于横向介子)有贡献。如果我们同样引入“较高自旋态”,比如,具有自旋s
为3/2的重粒子,就可以避开这... | 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 | (for example, the nebulae) in the universe, as according to the hypothesis the universe neither expands nor contracts. Such measuring rods we call “material rods” (“MR
”).
中文
It shall be shown here that the proffered hypothesis, based on the measuring system AC
+ MR
, is one of three alternative ways of formulati... | 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 “age of the world” is confirmed by other measurements based on atomic radioactivity clocks.)
中文
(AC
+ MR
). The above statement that MR
increases if measured in LR
is equivalent to saying that LR
decreases if measured in MR
. If M
R
is chosen and the clocks are not changed, the system AC
+ MR
is ado... | 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 Milne's “dynamical” time scale. It shall therefore be briefly examined.
中文
In AC
+ MR
, where characteristic atomic frequencies are assumed constant and cT
depends in some way upon T
,
(d
λ/λ)
T
+∆T
= (∆c
T
/T
)
T
+∆T
; (1)
on the other hand, the observational law of red-shifts (velocity-distance 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 | . If the usual assumption that ρ measures not (∆T
)2
but r
2
is upheld, our deductions would have to be altered and we would neither get (4) nor its equivalent (6), that is, Milne's scale of τ. Vice versa, if our assumption regarding ρ is upheld and if we consequently arrive in LC
+ MR
at Milne's τ-scale, in which... | 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,我们假定时间T
(基于原子钟)的绝对标度以(原子)年为单位,T
的当时值
为TP
= 1.86×109
。(基于原子放射钟的其他测量方法也可证实这一“世界年龄”。)
英文
(AC+MR
)。上文中提到,如果用LR
测量会发现MR
值增加了,这相当于说如果用MR
测量会发现LR
值减小。如果保持原子钟AC
不变,而用MR
代替LR
,那么就构成了另一种测量系统AC+MR
。LR
的减小意味着光速的减小(用MR
测量)。这就可解释远距离光的红移现象了,因为光速cT
在光发出的时刻T
–ΔT
时较大,所以λ
T
–∆T
大于λ
T
。
英文
(LC
+MR
)。本文... | 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 | 但是目前的经验
数据至少没有与我们的假设相矛盾,在我们的假设中∆T
2
(小于r
2
)是ρ的一种量度,因为“目前的证据显示,尽管观测到的光度(ρ)随距离减小,但并没有
预期的那样迅速
......”[3]
。
英文
(金世超 翻译;何香涛 审稿)
Evidence for Transformation of Mesotrons into Electrons
E. J. Williams and G. E. Roberts
Editor's Note
If seeing is believing, then Figure 2b
of this paper is a complete demonstratio... | 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 | With the object of obtaining information on this crucial point we constructed a large cloud-chamber (24 in. diameter, 20 in. deep) which, with its large sensitive period and volume, might catch a cosmic ray mesotron coming to the end of its range in the gas of the chamber. A recent photograph taken with this shows a me... | 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 the short δ-tracks, of which there are at least six obvious ones to be seen between C
and F
on the original negative.
中文
Fig. 1
中文
Fig. 2. a
and b
are arranged for stereoscopic observation with the naked eye, when usually the left eye sees the right-hand picture.
中文
That the dense track is that 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 | effect expected for a mesotron, it is more compatible with the latter than with a proton or any other known particle. The natural “curvature” of cloud-tracks due to multiple and single scattering is discussed by one of us in a paper now in the press (Physical Review
). It is there shown that towards the end of its ran... | 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 large energy of the electron shows, quite apart from Yukawa's theory, that mass has been annihilated—for the mesotron, even if we suppose it has disintegrated before “stopping”, has certainly less than 4 Mev. of kinetic energy. Actually, the large bending of the end of the mesotron track indicates (as already point... | 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 | 其终结处出现快电子的径迹,快电子的动能明显大于介子的动能,但是质量和能量则与介子的相当。这表明,介子会转化成为电子。在这种情况下介子与汤川秀树粒子之间的相同之处又更近了一步。根据汤川秀树的理论,观察到的这种现象可以这样描述,介子在衰变中发射了一个电子,从而构成了β衰变的一种最基本的形式。
英文
图1为其中一张立体像对照片的复制片。密集的径迹AF
是介子的,而从其终端远去的那条模糊的、靠近云室底部的径迹FG
则是快电子的。我们将会注意到,后者与碰巧在同一区域穿过云室的其他快速粒子的径迹在密度上是相当的。图2是立体像对照片的一个更大的复制片,仅仅显示了介子径迹的末端部分和出射的电子(2a
不如2b
的聚焦效果好)。图3为介... | 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 | 事实上,很有可能的是介子在停止电离后,其速度至少为每秒107
厘米,而其自由程比气体分子运动的值要大很多,因此寿命上限τ肯定会远小于上述的值。由宇宙射线介子的反常吸收推断出τ平均值的量级为10–6
秒。
英文
(胡雪兰 翻译;厉光烈 审稿)
Some Biological Applications of Neutrons and Artificial Radioactivity
*
J. H. Lawrence
Editor's Note
The discovery of nuclear transmutation and artificial means for inducing it stimulated 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 | During the past four years, workers at the University of California have been intensely interested in the biological applications of these products of the physicist, and recently a new medical-biological laboratory dedicated to this study and housing the new 220-ton cyclotron—the William H. Crocker Radiation Laboratory... | 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 | which these isotopes are employed follows.
中文
Table 1
中文
Radioactive hydrogen is written
, in contrast to ordinary hydrogen
and heavy hydrogen
, and has only recently been discovered by Alvarez and Cornog of this Laboratory. This newly labelled form is used in biological work and promises to become a valua... | 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 | Fig. 1. The 200-ton 60-inch cyclotron in the Crocker Radiation Laboratory on the Berkeley campus of the University of California. Standing by the corner of the magnet and adjusting the helium flow to the target chamber is the late Dr. Harold Walke, of the University of Liverpool. On the table in the foreground is an ex... | 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 | ) has been the most extensively used radioactive isotope. The ease of manufacture in the cyclotron and its relatively long half-life (14.3 days) make it ideal for biological studies. Chaikoff and his associates in their studies of phospholipid metabolism have shown that various kinds of neoplasms in animals have indivi... | 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 intense beam of neutrons produced by the cyclotron has made it possible to investigate their biological effects on various objects such as bacteria, plants, Drosophila eggs, animal tumours and normal mammals. This new penetrating form of radiation has intense biological effects, even greater than X-rays or gamma ra... | 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 | Radiation Laboratory.
中文
Although the great contribution of the new nuclear physics to the problems of biology and medicine is certainly the “labelled” or “tagged” isotope, nevertheless it seems important to pursue the possibilities of artificial radioactivity and neutron rays in cancer therapy until a more satisfa... | 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 | 尽管放射性碳的半衰期很短(20.5分钟),鲁宾、哈西德和卡门还是成功地将其用于对光合作用的研究之中。在C*O2
环境中生长的大麦类植物的叶子
†
,会形成放射性的碳水化合物,即使这种植物在暴露于C*O2
之前保存在黑暗中,结果也会如此。在植物中发现的大量放射性物质是水溶性的,而且并不包含碳水化合物、碳酸盐、酮酸或色素。农学院的珍妮和奥弗斯特里特使大麦生长在有K*存在的条件下,结果发现离子的摄入并不是一个单向过程,实际上相同种类的离子也可能在移入根部的同时移出根部。同一院系的斯托特和霍格兰研究了钾、钠、磷和溴的放射性同位素被生长旺盛的柳树和天竺葵植物的根部吸收后的向上运动。他们发现,当盐类被根吸收后,其中一部分会在很短的时间周... | 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 | 在沿其轨迹行进的过程中它们不断减速,将能量转移给空气分子,使它们发出紫色的光。然而实际上,是因为将一个具有放射性的靶置于粒子束出现的位置上,所以受到了轰击。在希望得到中子的地方用铍来作靶。照片由辐射实验室的助理主管唐纳德 · 库克西博士拍摄。
英文
毫无疑问“标记的”或“标示的”同位素是新核物理学对于生物学和医学问题所作出的一个巨大贡献,但是在我们对于癌症治疗问题得到更为令人满意的答案之前,继续探寻人工放射性和中子射线在癌症治疗中的可能似乎仍然是十分重要的。
英文
(王耀杨 翻译;王乃彦 审稿)
*
部分依据1939年8月31日及9月1日在邓迪举行的英国科学促进会A分会(数学和物理科学)上宣读的一篇论文。
†
... | 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 | Radium, a destroyer of living cells in active division, cannot be used to attack cancer without also damaging living normal cells of the circulating blood, etc. It can only be used for accessible cancers in the skin or surfaces of the body, which can be removed in nearly all cases by the knife or the diathermy needle 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 | Both radium and X-rays can produce, not only necrosis, but also cancer, and Sir Norman Walker considers that the use of X-rays for lupus should be abandoned. I know of an excellent laboratory servant who, only by continued observation and treatment, is kept, so far, free from cancer resulting from scars due to X-ray tr... | 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 | of January 27, p. 151, to his statement “that we would be little the worse off if all the radium now buried in deep holes for security from bombing remained there”, and seeks to make good this assertion by reminding us of some of the casualties of radiological practice. He has allowed these examples to stay in the fore... | 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 | Sir Leonard would like to see “the use of radium or X-rays being reserved for one or two places in the body where surgical operation is very difficult”. The publication “Medical Uses of Radium” has been issued yearly since 1922 by the Medical Research Council, and the Radium Commission has in recent years made annual r... | 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 | Sir Leonard Hill has collected a certain amount of gossip about radium and narrates a few cases of failure due to the misuse of radium which have come to his personal notice. To counterbalance his citation of deplorable failure, I could quote instances in my own experience where men with cancer of the throat, and elsew... | 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 system of properly controlled and measured dosage, which can be repeated at will with exactitude, has scarcely yet been fully evolved. Certainly, in the past haphazard applications have produced deplorable results, but these are new avoidable in consequence of the research work already done on the proper direction 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 | diagnosis. In carcinoma of the throat, treatment by the radium beam can be used without mutilation or loss of speech, and in cases too advanced for surgery. While surgery may be of some avail with cancer of the rectum and prostate, we have to admit with regret that all methods fail when the oesophagus or stomach is con... | 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 | 由于白血球减少症而导致的死亡,都是徒劳地试图用炸弹中的镭来治愈深部肿瘤而造成的。我能举出一个使用镭而造成伤害的实例,该患者目前正在圣约翰物理医学研究与治疗中心接受治疗;正是由于用镭治疗头颅侧面皮肤上的一小块上皮瘤,结果导致了可能终身无法治愈的颅骨坏死,其面积足有一个高脚酒杯的杯口那么大。
英文
已故的杰出外科医生弗尔尼沃先生罹患喉癌,在使用镭疗后不久即去世。他在自己的病历中留下了健康状况下降和不可治愈的神经痛的记录。我的一位亲戚因舌根部癌症而接受镭疗后,也遭受到这种无法忍受的神经痛,并且死于癌症复发;我还听到过许多类似的病例。很多优秀的临床医师都认为,镭的使用容易导致肿瘤转移。镭之所以流行,是因为它可以代替人们畏惧的手术刀,因... | 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 | 这种悲观论调与同一期杂志中另一篇由约翰·劳伦斯博士撰写的文章中对该问题的开明乐观态度,形成了鲜明的对比;劳伦斯博士来自加州大学,他在极好的便利条件下工作,而这些条件正是目前英国所缺乏的。劳伦斯和他的同事们正在研究“癌症治疗中应用人工放射性与中子射线的可能性,直至对该问题得到一个更令人满意的答案。”现在英国急需的,就是一个组织良好并能使射线的各种可能应用得以开发和扩展的放射学中心。一直以来,我的期望和理想就是建立这样一个中心来纪念卢瑟福勋爵,他对于放射治疗的可能性以及促使其进一步发展和完善的正确方法一直有着非常清醒的认识。
英文
伦纳德·希尔爵士收集了一些关于镭的流言,又讲述了几个引起他关注的由于错误使用镭而导致失败的病例。为了... | 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 | 伊夫
英文
(王耀杨 翻译;杨志 审稿)
Cancer-Producing Chemical Compounds
J. W. Cook
Editor's Note
That some substances are carcinogenic was recognized at least since the eighteenth century, when some component of soot was deemed responsible for the high incidence of scrotal cancer in chimney sweeps. This led to a recognition 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 | In the earlier work on the carcinogenic properties of substances the skin of the mouse was usually employed as the test object. This was due to a number of reasons. Results could be expected comparatively rapidly; the ear of the rabbit, which had been first used, was less satisfactory in this respect. Moreover, the mod... | 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 | subcutaneous tissues, the peritoneal cavity, the liver, the prostate, the forestomach, the brain, and the spleen; and this list is not exhaustive. Less widespread in their effect are members of other classes of compounds, where usually carcinogenic action has not been shown except in a single organ. In this connexion 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 | increase was not wholly related to the presence of tar in the dust, and the results of the experiments do not directly implicate such an agent in the increase of the human disease. Furthermore, it is considered by many authorities that the recorded increase in lung cancer is largely accounted for by improved methods 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 | shown to have such biological activity, and in the generalizations which it has been possible to arrive at regarding the correlation of carcinogenic activity with molecular structure and with other properties.
中文
The benzanthracene group is not the only group of polycyclic hydrocarbons with carcinogenic properties. ... | 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 many unsuccessful attempts have been made to induce experimental tumours with these bases. Some two years ago, however, the production of bladder tumours in dogs given, subcutaneously and orally, large daily doses of a high grade of commercial β-naphthylamine was reported by American workers. It was doubtless the 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 | One of the azo dyes found to be carcinogenic to the liver by the Japanese workers, namely, p
-dimethylaminoazobenzene (IX), was formerly used as a food colouring matter under the name of “butter yellow” and has also been used in dyeing leather. Fortunately, its use in these respects appears now to be obsolete. In Grea... | 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 puzzling and in some ways disconcerting feature of the carcinogenic agents now known is their variety and their apparent lack of correlation. It may be recalled that cancer may be induced not only by the classes of compound reviewed in this article, but also by several other agencies. The malignant tumours which aris... | 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 | 此外,在当前对这些物质进行简要描述的准备阶段,人们已经注意到工业引发的癌症与相应致癌物之间存在关联。
英文
早期研究致癌物的特性时,经常用小鼠的皮肤作为测试对象。这是有多种原因的。首先,这样可以较快地得到结果,而最早使用兔子耳朵作为测试对象时这方面就不太令人满意。另外,因为研究中必须使用的天然混合物有毒性并能引起炎症反应,因此在实验中待检物质的给药方式受到很大程度的制约。现在,人们已经可以提纯出具有高致癌性的单一化合物,许多这样的问题已经得到了解决。近几年来,一些新的给药技术已经得到了发展,因而已经可以在好几种动物的多种组织中诱导出恶性肿瘤。这些以及其他一些相关研究的结果表明,对于某些品系的动物,肿瘤容易在某些特定器官中自发产... | 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 | 出现这种错误的原因应该是最初从煤焦油中获得的的䓛由于提纯不彻底而含有杂质。诸如此类的相关情况使一些研究者将注意力投向了䓛的衍生物。人们以随机选择的方式合成了大量䓛的同系物,但通过生物学检测发现这些化合物并无致癌活性。最近,基于对1,2–苯并蒽的各种致癌衍生物与3,4–苯并菲的结构关系的考察,休伊特合成了(《英国化学会志》,即将出版)1,2–二甲基䓛(VI),并且通过施用于小鼠皮肤进行测试发现这种烃类确实具有致癌活性。
英文
英文
多年来人们一直认为,在化学工业的某些部门特别是染料制造部门工作的工人比普通人群更容易患膀胱癌。长期以来,这种癌症被认为是“苯胺癌”,人们一直认为该病的起因是人体吸收了含氮碱基,例如联苯胺和萘胺,... | 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
(吴彦 翻译;秦志海 审稿)
Molecular Structure of the Collagen Fibres
W. T. Astbury and F. O. Bell
Editor's Note
Collagen is the fibrous protein that constitutes connective tissue—tendons and such structures in living things. William T. Astbury from the University of Leeds had built a reputation for himself during the 1930s... | 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 | 中文
Thus not only are one third of the residues glycine residues, but also, except for one residue in eighteen, another third are either proline or hydroxyproline residues; that is to say, are of the form:
中文
The table shows too that there cannot be fewer than 72 residues in the gelatin “molecule” (there will not 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 | is readily accounted for by the preponderance of imino residues. When we allow for this and the glycine content, there seems to be only one reasonable solution, represented by the scale model shown in the accompanying illustration. The basic sequence is –P–G–R
–, where (with the exception of one residue in eighteen) 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 | Astbury, W. T., C.R. Lab. Carlsberg
, 22
, 45 (1938) (Sørensen Jubilee Vol.); Trans. Faraday Soc
., 34
, 377 (1938); Ann. Rev. Biochem
., 8
,113(1939); Ann. Rep. Chem. Soic
., 35
, 198 (1939).
Astbury, W. T., Trans. Faraday Soc
., 29
, 193 (1933); Cold Spring Harbor Symposia on Quantitative Biology
, 2
, 15... | 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 | 假定侧链与主干之间的倾角为β,而一个氨基酸残基沿纤维轴方向的平均长度为L
Å,那么:
即:
L
= 2.6 sinβ(近似值)
因此L
大约不会超过2.6 Å。虽然只是粗略估算,不过这已经足够准确地证实弧长约为2.86 Å的强子午线与一个残基的平均长度是有关联的。
英文
(3)如果实际长度确实如此(目前看来这是很有可能的),并且残基一个接一个地连成一行,那么根据表中的数据,分子内模块在沿着纤维轴方向上的最小长度约为72×2.86Å。这个长度太小了,不但根本无法包括上述表格中被忽略的其他氨基酸残基,如组氨酸,而且也不足以解释威科夫与科里[4]
、克拉克及其合作者们[5]
所报道的子午线长度。对他们的数据所能作出的最... | 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 | XPERIMENTS on the processes arising in thorium under neutron bombardment have shown that nuclear fission is induced only by fast neutrons of energies of about 2 Mev. or more. There exists also a radiative capture process producing an isotope of thorium (Th 233) of 26 min. half-life; this process has a resonance charact... | 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 | contained the neutron source 3.3 cm. below the surface in such a way that the source just touched the upper edges of the cadmium screened cavity.
中文
The activity of the dysprosium detector was measured with a Geiger-Müller counter with 0.1 mm. aluminium walls connected to an amplifier. The dysprosium, the half-life ... | 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 influence of inelastic scattering, the cadmium was placed by turns either directly on the exposed face of the detector (with the thorium put upon that), or between the neutron source and the thorium absorber. No difference could be detected. Thus the inelastic scattering does not give rise to thermal neutrons in an... | 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 | Th respectively being produced, it is clear that if on account of their nearly equal half-life the efficiency of the β-rays is assumed to be approximately the same, the β-ray activities due to thermal neutrons (corrected for equal numbers of nuclei) must be proportional to the respective cross-sections:
中文
From ear... | 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 | 为了进行吸收测量,我们把钍直接放在带镉屏或者不带镉屏的镝片上,这样中子轰击时一般就必须通过厚度为1.2厘米的钍片,其相当于13.4克的钍。
英文
具体的实验做法如下。在一个3.8厘米厚的石蜡平板上,挖出一个1.3厘米深的矩形空腔,底部和侧面都覆盖有0.5毫米厚的镉,这样使得热中子只能从上面进入。把这个石蜡板放在另外两个石蜡板的中间,用这种方法组成一个高11.5厘米、底面为25厘米×25厘米的长方体。镝放在被镉屏蔽了的空腔的底部。最上面的石蜡平板里含有一个中子源,中子源距离上表面3.3厘米,这样放置后,中子源就刚好接触到了被镉屏蔽的空腔的上边界。
英文
镝探测器的放射性是由盖革–米勒计数器进行测量的,计数器的壁是厚度为0.... | 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
(胡雪兰 翻译;朱永生 审稿)
The Mass Centre in Relativity
M. Born and K. Fuchs
Editor's Note
Part of the interest of this paper is its authorship. Max Born was a German émigré to Britain, awarded a Nobel Prize in 1954 for his work on quantum mechanics, while Klaus Fuchs was also a German exile working as a physicist in Brit... | 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 | Quantum mechanics circumvents this problem by considering interactions as produced by emission and reabsorption of other particles. We were induced to reconsider this problem by its bearing on a relativistic and “reciprocal” formulation of second quantization. Without touching this question, we shall state here some si... | 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 | Γ is invariant, hence π is invariant also. π has a simple meaning in the case of equal masses. In the rest system Σ°, where
, we have m
1
– m
2
= m
–
=0, and
; hence
. This shows that π is the length of the vector π
representing relative momentum.
中文
For different masses π
can be described as the relative... | 400套付费套装书 |
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