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801.
Walter E. Gross 《Annals of science》2013,70(5):407-427
Early geological investigations in the St David's area (Pembrokeshire) are described, particularly the work of Murchison. In a reconnaissance survey in 1835, he regarded a ridge of rocks at St David's as intrusive in unfossiliferous Cambrian; and the early Survey mapping (chiefly the work of Aveline and Ramsay) was conducted on that assumption, leading to the publication of maps in 1845 and 1857. The latter represented the margins of the St David's ridge as ‘Altered Cambrian’. So the supposedly intrusive ‘syenite’ was regarded as younger, and there was no Precambrian. These views were challenged by a local doctor, Henry Hicks, who developed an idea of the ex-Survey palaeontologist John Salter that the rocks of the ridge were stratified and had formed a Precambrian island, round which Cambrian sediments (now confirmed by fossil discoveries) had been deposited. Hicks subsequently proposed subdivision of his Precambrian into ‘Dimetian’, ‘Pebidian’, and (later) ‘Arvonian’, and he attempted correlations with rocks in Shropshire, North Wales, and even North America, seeking to develop the neo-Neptunist ideas of Sterry Hunt. The challenge to the Survey's work was countered in the 1880s by the Director General, Geikie, who showed that Hicks's idea of stratification in the Dimetian was mistaken. A heated controversy developed, several amateur geologists, supported by a group of Cambridge Sedgwickians, forming a coalition of ‘Archaeans’ against the Survey. Geikie was supported by Lloyd Morgan. Attention focused particularly on Ogof Lle-sugn Cave and St Non's Arch, with theory/controversy-ladenness of observations evident on both sides. Evidence from an eyewitness student record of a Geological Society meeting reveals the ‘sanit`ized’ nature of the official summary of the debate in QJGS. Field mapping early in the twentieth century by J. F. N. Green allowed a compromise consensus to be achieved, but Green's evidence for unconformity between the Cambrian and the Dimetian, obtained by excavation, can no longer be verified, and his consensual history of the area may need revision. Unconformity between the Cambrian and the Pebidian tuffs is not in doubt, however, and Precambrian at St David's is accepted. The study exhibits features of geological controversy and the British geological community in the nineteenth century. It also furnishes a further instance of the great influence of Murchison in nineteenth-century British geology and the side-effects of his controversy with Sedgwick. 相似文献
802.
803.
Piero E. Ariotti 《Annals of science》2013,70(6):611-624
In the histories of science, technology and aviation Christiaan Huygens has been unjustly neglected. Documents in the corpus of his works show a life-long interest in the problem of human flight together with some considerable anticipations of, and contributions to, its solution. He was among the first, if not the first, in perceiving the potential of the heavier-than-air approach. He clearly recognized the need for a powerful, mechanical motive source. He stated the first laws of aerodynamics and conceived the modern propeller for propulsion. He was the first to conceive of the aeroplane. His approach to the problem of flying was both global and scientific. 相似文献
804.
R.E.W. Maddison 《Annals of science》2013,70(2):196-198
805.
A central thesis of Steven French's brand of ontic structural realism has always been his eliminativism about objects. Unsurprisingly, this bold and controversial thesis has seen a lot of critical discussion. In his book The Structure of the World—Metaphysics & Representation, French accordingly defends this thesis against a range of challenges. A novel feature of this defense is the use of dependence relations to articulate his eliminativism. In this paper I take a critical look at French's defense of eliminativism and argue that the dependence relations invoked do not eliminate objects. 相似文献
806.
Zusammenfassung 2, 2:6, 2-Terpyridin gibt mit Aethylendibromid ein diquartäres Salz, das durch Reduktion mit Zink eine Radikalkation liefert. Es handelt sich um ein Redox-System und das Salz besitzt herbizide Wirksamkeit. 相似文献
807.
Zusammenfassung Durch Immunofluoreszenz wird eine Kreuzreaktion zwischen Tumoren des gleichen histologischen Typs, jedoch keine solche zwischen verschiedenartigen Tumoren des Hundes festgestellt.
Supported, in part, by a National Science Foundation fellowship. 相似文献
Supported, in part, by a National Science Foundation fellowship. 相似文献
808.
Zusammenfassung Es wird gezeigt, dass Larven der grossen Wachsmotte durch oral appliziertes «Exotoxin» vonBacillus thuringiensis vergiftet werden, die LD50 aber ca. 250mal grösser ist als bei parenteraler Applikation. Oral verabreichtes «Exotoxin» wird zu einem grossen Teil im Raupendarm inaktiviert. Es konnte eine mathematische Beziehung zwischen der Inkubationszeit und der Inaktivierung des «Exotoxins» gefunden werden, die für einen enzymatischen Abbau des «Exotoxins» spricht. 相似文献
809.
Formation of anaphylatoxin in human serum 总被引:1,自引:0,他引:1
W. Vogt G. Bodammer E. Lufft G. Schmidt 《Cellular and molecular life sciences : CMLS》1969,25(7):744-745
Zusammenfassung Es ist möglich, auch in menschlichem Serum eine Anaphylatoxinbildung (AT) durch Kontaktaktivierung oder Kobragift zu induzieren. Wegen der geringen Mengen, die entstehen, muss das wirksame Prinzip vor dem biologischen Nachweis angereichert werden. Menschliches AT verhält sich in allen untersuchten Eigenschaften wie AT aus anderen Plasmaarten. Es unterscheidet sich von dem darmkontrahierenden Spaltprodukt aus der menschlichen Komplementkomponente C3, das mithin nicht als AT angesprochen werden kann. 相似文献
810.
E. V. Orsi M. Franko L. Rodriquez H. T. Holden 《Cellular and molecular life sciences : CMLS》1969,25(2):181-182
Résumé Nous avons trouvé le virus SV40 chez le singeCercopithecus aethiops présumé non infecté. Par la méthode de culture des cellules du rein et en effectuant des passages rapides nous avons pu démontrer l'existence du virus même chez les animaux dépourvus d'anticorps et même dans le cas où le virus n'apparaissait pas durant le premier passage. 相似文献