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Eugen Goldstein, Wilhelm Wien, en de kanaalstralen, 1886-1912  [cached]
Henk de Regt
Tijdschrift voor de Geschiedenis der Geneeskunde, Natuurwetenschappen, Wiskunde en Techniek , 1989,
Abstract: Eugen Goldstein, Wilhelm Wien, and Canal Rays, 1886-1912 Canal rays ('Kanalstrahlen' in German), or positive rays, played an important role in the development of physics in the early years of this century. However, their role has generally been neglected by historians of science. Canal rays, not widely known today, were discovered when a perforated cathode was used in a gas discharge. They are emitted from the holes into the space on the backside of the cathode. In this article, the early history of canal rays is analyzed, starting from Eugen Goldstein's discovery of the phenomenon in 1886 and Wilhelm Wien's subsequent investigations from 1897 until 1912. Wien argued that canal rays consist of positively charged particles, which are the counterparts of the negatively charged cathode rays (electrons). After having demonstrated this experimentally, he focused his research on the question of the nature of the processes involved in the production of the rays. This led him to conclude that the canal ray particles should be identified with the ions of the gas, and to propose a theory about their behaviour. After this historical description, the article examines possible reasons why the canal rays were ignored for such a long time after their discovery, the highly experimental character of Wien's investigations (in spite of his reputation as a theoretician), and the relationship between Wien's work and J.J. Thomson's research on canal rays.
Laboratorium der bürgerlichen Welt. Deutsche Wissenschaft im 19. Jahrhundert  [cached]
Pierangelo Schiera
Scienza & Politica : per una Storia delle Dottrine , 1992, DOI: 10.6092/issn.1825-9618/3013
Abstract: Laboratorium der bürgerlichen Welt. Deutsche Wissenschaft im 19. Jahrhundert
La primavera de Praga en el diario comunista Berliner Zeitung  [cached]
Emilia Martos Contreras
Historia Actual Online , 2009,
Abstract: El siguiente artículo pretende analizar el tratamiento informativo dado por el diario comunista Berliner Zeitung a la llamada Primavera de Praga. El gobierno de la República Democrática Alemana fue uno de los más alarmista y crítico con las medidas reformista de Alexander Dubcek en Checoslovaquia. Temeroso de que las “medidas liberalizadoras” cruzaran la frontera utilizó todas sus armas, entre ellas los Medios de Comunicación, no sólo para acabar con las reformas, sino sobre todo mostrarles a sus ciudadanos lo peligrosas y erróneas que eran.
Johannes Burkhardt, Deutsche Geschichte in der Frühen Neuzeit, München 2009  [PDF]
Eric Piltz
AEON : Forum für Junge Geschichtswissenschaft , 2010,
Abstract: Recension of Johannes Burkhardt, Deutsche Geschichte in der Frühen Neuzeit, München 2009
Deutsche Rechtsgeschichte. Land und Stadt - Burger und Bauer im Alten Europa  [cached]
Gerhard Dilcher
Scienza & Politica : per una Storia delle Dottrine , 2000, DOI: 10.6092/issn.1825-9618/2869
Abstract: Deutsche Rechtsgeschichte. Land und Stadt - Bürger und Bauer im Alten Europa
Europeana und die Deutsche Digitale Bibliothek (DDB): Bedeutung und Herausforderung für die deutsche Bibliothekslandschaft
Nina Baueregger
Perspektive Bibliothek , 2012, DOI: 10.11588/pb.2012.2.9456
Abstract: Dieser Beitrag gibt einen überblick über die Ziele, Inhalte und Hintergründe von Europeana sowie der Deutschen Digitalen Bibliothek (DDB) und leitet daraus als zentrale Bedeutung und Herausforderung an das deutsche Bibliothekswesen das Thema Integration auf interinstitutioneller, internationaler, zeitlicher und rechtlicher Ebene ab. Insbesondere geeignete integrierende, sparten- und l nderübergreifende Organisationsstrukturen, Digitalisierung, Langzeitarchivierung, eine nachhaltige Finanzierung und offene Urheberrechtsfragen werden in diesem Zusammenhang kurz dargestellt.
J.H. van ’t Hoffs theorie van de verdunde oplossingen (1886)
H.A.M. Snelders
Tijdschrift voor de Geschiedenis der Geneeskunde, Natuurwetenschappen, Wiskunde en Techniek , 1987,
Abstract: J.H. van 't Hoffs theory of diluted solutions (1886) In his Etudes de dynamique chimique (1884).J.H. van 't Hoff was confronted with the problem of the magnitude of the attraction of water by salts. He wondered whether it is possible to measure this force, i.e. the affinity, in the simple case of an aqueous solution. Hugo de Vries drew his attention to Wilhelm Pfeffer's experiments on osmotic pressure. This led to van 't Hoffs theory of osmotic pressure, which he formulated in 1884-1885 and which was published in 1885-1887. Van 't Hoff found an analogy between the osmotic pressure and the gas pressure. The general gas law PV=RT is also applicable to dilute solutions, although for electrolytes a factor i had to be introduced: PV=iRT. It was Svante Arrhenius who suggested that i is equal to the number of ions. In 1887 Arrhenius published his theory of electrolytic dissociation. Connected with van 't Hoffs theory of osmotic pressure, the definitive formulation of the theory of dilute solutions was obtained. Soon discussions were held about the theory of solutions. The British Association for the Advancement of Science organized a meeting in Leeds in 1893 where the new theories were fiercely attacked by a number of British scientists. In April 1893 the meeting of the Nederlandsch Natuur- en Geneeskundig Congres (Dutch Physical and Medical Congress) in Groningen reached favourably to the new ideas, On January 8, 1894, van 't Hoff lectured on the genesis of the theory of solutions before the Deutsche Chemische Gesellschaft in Berlin. It is remarkable that he asked himself whether the theory of electrolytic dissociation conforms to reality. Although his student Jacob Jan Alexander Wijs had determined the value of the dissociation constant of water (1893), van 't Hoff ended his lecture with the intriguing question: "Is the theory of electrolytic dissociation proved in this way? By no means. But it wholly unexpectedly has supplied much in the field of saponification." It is not clear whether Van 't Hoff had his doubts on the degree of reality of the theory of electrolytic dissociation or whether he did not want to take the risk of a confrontation with his opponents.
G. Ros, Adalbart von Bornstadt und seine Deutsche-Brüsselere Zeitung. Ein Beitrag zur Geschichte der deutschen Emigrantenpublizistik im Vorm rz  [cached]
J.M.H.J. Hemels
BMGN : Low Countries Historical Review , 1995,
Abstract:
Tel Aviver Jahrbuch für deutsche Geschichte, XXVII-1998  [cached]
Dominique Trimbur
Bulletin du Centre de Recherche Fran?ais de Jérusalem , 2008,
Abstract: Although Israel has only one German department, in Jerusalem, German studies are flourishing in this country. Not only has the Israeli University system just been enhanced by a new center devoted to this field (in Beer Sheva, under Professor Frank Stern), the Institute of German History of Tel Aviv University has confirmed its dynamism and capabilities for in-depth work with the publication of the new Tel Aviver Jahrbuch für deutsche Geschichte. Complementing the broad range of works publish...
La educación militar en Colombia entre 1886 y 1907
Rey Esteban,Mayra Fernanda;
Historia Crítica , 2008,
Abstract: in historiography of the colombian military, the process known as the military reform and the professionalization of the national army is said to have begun in 1907. with this in mind, the article investigates a fundamental issue: military education, or the drilling of the troops and the training of the officers in the military schools between 1886 and 1907. its aim is to understand how the army attempted to achieve this goal. there were both advances and steps backward toward such goals during these years.
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