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1.
Dynamis (Granada) ; 43(2): 339-365, 2023. ilus
Artigo em Espanhol | IBECS | ID: ibc-229571

RESUMO

En 1966, 137 toneladas de mineral de uranio español llegaron al puerto de Nueva Orleans procedentes del puerto de Cádiz. En este artículo quiero utilizar este viaje que conectó agentes políticos, industriales y empresariales con capacidades y experiencias técnicas, para explorar el uranio como un objeto híbrido —físico, técnico y diplomático—. El uranio conectó los intereses de las autoridades franquistas con los de los científicos y empresarios de la industria eléctrica. Sirvió al régimen de Franco para formar investigadores en nuevos métodos y prácticas experimentales y también para popularizar las políticas e ideologías atómicas de Estados Unidos. Al tiempo que alimentó los reactores nucleares, el uranio generó nuevos espacios disciplinares, modificó paisajes y diseñó nuevas cartografías industriales y administrativas. Además de ser una pieza clave en la política exterior del régimen franquista —le sirvió al régimen español para alinearse con el pensamiento occidental imperante sobre los usos civiles de la energía nuclear—, internamente sirvió para abandonar los discursos autárquicos y reforzar el poder de los tecnócratas, que utilizaron la energía atómica para transformar la producción eléctrica española. Este viaje cambió la materialidad del mineral de uranio, su física y su química, y también sus significados. (AU)


In 1966, 137 tons of Spanish uranium ore arrived at the port of New Orleans from the port of Cádiz. In this paper, I want to use this trip, which involved political, industrial, and business agents as well as technical capabilities, to explore the uranium as a hybrid object - physical, technical and diplomatic. This material connected the interests of the Franco authorities, scientists, and businessmen from the electrical industry. It served the Franco regime in training researchers, in buying and importing technologies, methods and experimental practices, and in introducing ways to popularize atomic policies and ideologies from the United States. Uranium was a fuel that not only powered nuclear reactor but also fed new disciplinary spaces, modified landscapes, and sketched new industrial and administrative cartographies. Besides being a key piece of the Franco regime’s foreign policy —it was useful to the Spanish regime to align itself with prevailing Western thought on the civil uses of nuclear energy— it served internally to effectively abandon autarchic discourses and strengthen the power of the technocrats, who used atomic energy to transform Spanish electrical production. The materiality of uranium ore changed with travel and also its meanings. (AU)


Assuntos
História do Século XX , Urânio/história , Energia Nuclear/história , Energia Nuclear/economia , Espanha , Estados Unidos , Viagem/história , Expedições
4.
Appl Radiat Isot ; 119: 6-15, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27829185

RESUMO

This study reports the use of the U-series radionuclides 238U and 234U for dating two soil profiles. The soil horizons developed over sandstones from Tatuí and Pirambóia formations at the Paraná sedimentary basin, São Paulo State, Brazil. Chemical data in conjunction with the 234U/238U activity ratios (AR's) of the soil horizons allowed investigating the U-isotopes mobility in the shallow oxidizing environment. Kaolinization and laterization processes are taking place in the profiles sampled, as they are especially common in regions characterized by a wet and dry tropical climate and a water table that is close to the surface. These processes are implied by inverse significant correlations between silica and iron in both soil profiles. Iron oxides were also very important to retain uranium in the two sites investigated, helping on the understanding of the weathering processes acting there. 238U and its progeny 234U permitted evaluating the processes of physical and chemical alteration, allowing the suggestion of a possible timescale corresponding to the Middle Pleistocene for the development of the more superficial soil horizons.


Assuntos
Poluentes Radioativos do Solo/análise , Solo/química , Urânio/análise , Brasil , Fenômenos Geológicos , História Antiga , Datação Radiométrica/métodos , Poluentes Radioativos do Solo/história , Fatores de Tempo , Urânio/história , Tempo (Meteorologia)
5.
Rev Hist Pharm (Paris) ; 63(387): 407-16, 2015 Sep.
Artigo em Francês | MEDLINE | ID: mdl-26529893

RESUMO

After a biographic reminder on André Lancien, pharmacist of Marine, we describe her activities of research. The first ones concern the radium and the uranic by-products, but the main part concerns the development of a process of obtaining by electric way of stable colloidal solutions to very fine metallic or metalloïdic particles. These colloids were applied to the therapeutics in diverse domains, prefiguring before the term existed what we call now nanomedicine.


Assuntos
Indústria Farmacêutica/história , Nanomedicina/história , Farmácias/história , Coloides/química , França , História do Século XX , Humanos , Metais/química , Farmacêuticos , Rádio (Elemento)/história , Urânio/história
7.
Acta Hist Leopoldina ; (63): 485-502, 2014.
Artigo em Alemão | MEDLINE | ID: mdl-24974619

RESUMO

The 50-year relationship between Weizsäcker and Heisenberg spanned the highpoints of discovery and dictatorship during the 1930s, extended into the war-time uranium project, the post-war controversy over that project, debates over West German nuclear policy, and the philosophical implications of modern physics. This paper explores the interaction between these two leading figures during that difficult and significant half-century.


Assuntos
Academias e Institutos/história , Socialismo Nacional/história , Disciplinas das Ciências Naturais/história , Física Nuclear/história , Filosofia/história , Política , Política Pública/história , Pesquisa/história , Urânio/história , Alemanha , História do Século XX , História do Século XXI
8.
Int J Hyg Environ Health ; 216(4): 499-507, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22939882

RESUMO

This paper describes the methods and results of an occupational exposure assessment covering 30 years of operation of the EURODIF establishment (1978-2008). The exposure assessment includes radiological, physical and chemical hazards, and takes into account of organizational changes at the establishment. Furthermore, it includes efforts to better quantify the levels of exposures using available industrial hygiene and health physics data. In total, 227 workers participated in the assessment of 26 different occupational exposures in 102 general workstations through 1978-2008. Only 7% of exposure levels were rectified by experts for internal consistency reasons. Noise, heat, trichloroethylene and soluble uranium compounds were the most prevalent exposures at the plant although their levels tended to decrease across time. Assessments of occupational exposure to noise based on JEM exposure levels were fairly well correlated with noise measurement data (Spearman's correlation coefficient, ρ=0.43) while JEM-based assessments of uranium exposure were not well correlated with uranium atmospheric measurements. This study demonstrates the importance of non-radiological exposure in the nuclear fuel industry and highlights the difficulties in managing the risks arising from these exposures. Occupational exposures remain difficult to quantify due to the scarcity of reliable monitoring data and the absence of binding occupational exposure limits for some of considered hazards.


Assuntos
Metalurgia/história , Exposição Ocupacional/história , Poluentes Ocupacionais do Ar/análise , Poluentes Ocupacionais do Ar/história , Carcinógenos/análise , Carcinógenos/história , Poeira/análise , Monitoramento Ambiental , França , História do Século XX , História do Século XXI , Temperatura Alta , Humanos , Mutagênicos/análise , Mutagênicos/história , Ruído , Exposição Ocupacional/análise , Doses de Radiação , Teratógenos/análise , Teratógenos/história , Urânio/análise , Urânio/história
9.
Kwart Hist Nauki Tech ; 57(1): 23-38, 2012.
Artigo em Polonês | MEDLINE | ID: mdl-22849242

RESUMO

For many reasons the year 1898 was unusual for Maria Sklodowska-Curie and her husband. After defining the subject of the doctoral thesis and choosing Henri Becqerel as thesis supervisor, Maria started intensive experimental work. In the allotted room called storeroom, in conditions that were far too inadequate, they managed to put up a unique measuring equipment composed of instruments whose originator was Pierre Curie. In the ionization chamber and in the piezoelectric quartz charges formed, whose mutual neutralization was shown by the quadrant electrometer. Ionization current, which was measured quantitatively, was proportional to the radiation of the sample. Studying many elements, their compounds and minerals enabled Maria to state that uranium is not the only element endowed with the power of radiation; the second one turned out to be thorium. Anomaly detected in the radiation of uranium minerals made it possible for Maria to draw an extremely important conclusion: radioactive uranium and thorium are not the only elements endowed with such an attribute. Pitchblende, which was studied by the Curie couple, had to contain also other radioactive substances. Gustave Bémont also participated in the chemical analysis of the uranium ore and it is worth reminding that he was involved in the discovery of polonium and uranium. The phenomenon of radioactivity couldn't have been explained if it was not for the sources of strong radioactivity. Those sources undoubtedly could have been the discovered elements but their scanty content in the uranium ore made their isolation very difficult and laborious. Access to industrial remains after procession of pitchblende from Jachymov (Sankt Joachimstahl), obtained owing to the mediation of Eduard Suess, provided the source of this raw material. From it, in a shack also called le hangar, the Curie couple isolated the first samples of the radium salt. This element, later extracted by discoverers on a grand scale and handed over in a various forms to researchers and institutions, became a foundation of physics and chemistry of radioactive elements.


Assuntos
Química Analítica/história , Prêmio Nobel , Radioatividade , Rádio (Elemento)/história , Feminino , França , História do Século XIX , Humanos , Laboratórios/história , Masculino , Radiologia/história , Urânio/história
10.
Artigo em Inglês | MEDLINE | ID: mdl-21785255

RESUMO

Shortly before the Second World War time, Nishina reported on a series of prominent nuclear physical and radiochemical studies in collaboration with Kimura. They artificially produced (231)Th, a member of the natural actinium series of nuclides, by bombarding thorium with fast neutrons. This resulted in the discovery of (237)U, a new isotope of uranium, by bombarding uranium with fast neutrons, and confirmed that (237)U disintegrates into element 93 with a mass number of 237. They also identified the isotopes of several middle-weighted elements produced by the symmetric fission of uranium. In this review article, the highlights of their work are briefly summarized along with some explanatory commentaries.


Assuntos
Fissão Nuclear , Urânio/história , Arquivos , História do Século XX , Isótopos , Tório/química , Tório/história , Urânio/química
12.
J Vasc Surg ; 53(1 Suppl): 3S-5S, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20869835

RESUMO

INTRODUCTION: Radiation was discovered just slightly more than a century ago, with a profound effect on both industry and medicine. Several notable scientists were key in bringing radiation to the forefront. METHODS: Historical review of scientists who played key roles in the discovery of radiation and its use in medicine are reviewed. RESULTS: Wilhelm Roentgen, Henri Becquerel, and Marie and Pierre Curie's work is reviewed. The field of radiation safety was born to protect those handling radiation in addition to patients who received radiation for medical purposes. CONCLUSION: Radiation use in medicine continues to evolve after notable discoveries by Nobel Prize-winning scientists.


Assuntos
Radiografia/história , França , Alemanha , Física Médica/história , História do Século XIX , Humanos , Lesões por Radiação/história , Radioatividade , Radioterapia/história , Urânio/história , Raios X
13.
J Occup Environ Hyg ; 4(2): 71-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17175512

RESUMO

A chemical exposure assessment was conducted for a cohort mortality study of 6157 chemical laboratory workers employed between 1943 and 1998 at four Department of Energy sites in Oak Ridge, Tennessee, and Aiken, South Carolina. Previous studies of chemical laboratory workers have included members within professional societies where exposure assessment was either limited or not feasible, or chemical processing employees where laboratory and production workers were combined. Because sufficient industrial hygiene records were unavailable for all four sites, weighted duration of employment was used as a surrogate for the magnitude of exposure. Potential exposure indices were calculated for each worker using number of days employed and weighting factors for frequency of contact and year of employment. A total of 591 unique laboratory job titles indicative of a chemical laboratory worker were collapsed into 18 general job title categories. Through discussions with current and retired workers, along with examination of historical organizational charts and job descriptions, the percentage of time with activities involving the direct handling of chemicals in the laboratory was estimated for each job title category. Scaled weighting factors of 1, 0.6, 0.3, and 0.05 were assigned to the job title categories representing 100%, 60%, 30%, and 5% of daily activities handling chemicals, respectively. Based on limited industrial hygiene monitoring data, personal radiation monitoring records, and professional judgment, weighting factors that declined 4% annually were applied to each year to account for improvements in laboratory technique, advancements in instrumentation, improvement in engineering controls, and increased safety awareness through time. The study cohort was separated into three categories of chemical exposures based on department level information: (1) inorganic, (2) mixed inorganic and organic, and (3) unknown. Potential exposure indices ranged from 0.15 to 6824.5 with a median value of 377.5 and a mean equal to 884.2. This exposure assessment method is useful for epidemiologic analyses when quantitative exposure data are absent or insufficient.


Assuntos
Poluentes Ocupacionais do Ar/história , Laboratórios , Exposição Ocupacional/história , Poluentes Ocupacionais do Ar/análise , Partículas beta , Raios gama , História do Século XX , Humanos , Ácido Fluorídrico/análise , Ácido Fluorídrico/história , Mercúrio/análise , Mercúrio/história , Exposição Ocupacional/análise , Monitoramento de Radiação , Tricloroetileno/análise , Tricloroetileno/história , Urânio/análise , Urânio/história
16.
Cancer Radiother ; 3(1): 19-29, 1999.
Artigo em Francês | MEDLINE | ID: mdl-10083860

RESUMO

Henri Becquerel presented the discovery of radium by Pierre and Marie Curie at the Paris Académie des Sciences on 26th December 1898. One century later, radium has been abandoned, mainly for the reason of radiation safety concerns. It is, however, likely that modern techniques of brachytherapy are the successors of those designed for radium sources, and that radium has cured thousands and thousands patients all over the word for about 80 years. The history of discovery and medical use of radium is summarised.


Assuntos
Radioterapia/história , Rádio (Elemento)/história , França , História do Século XIX , História do Século XX , Polônio/história , Radioatividade , Rádio (Elemento)/uso terapêutico , Urânio/história
17.
Rev Prat ; 45(6 Spec No): 7-10, 1995 Mar 15.
Artigo em Francês | MEDLINE | ID: mdl-7754330

RESUMO

In March 1896, not long after the discovery of X rays by W. Röntgen, H. Becquerel discovers the "uranic rays" emitted by the element uranium. In 1898, M. Curie observes that minerals containing uranium are more radioactive than the uranium they contain; she infers that yet unknown radioactive elements are present in minute quantities in these minerals. A few months later, P. and M. Curie, after an exhausting labour, discover polonium and radium. The "physiological action" of the rays emitted by radium are observed for the first time in 1900-1901. E. Rutherford and F. Soddy show, in Montreal, in 1902, that radioactivity is a spontaneous transmutation of one chemical element in another. The discovery of the atomic nucleus and of nuclear reactions will lead F. and I. Joliot-Curie to discover artificial radioactivity in 1934.


Assuntos
Radioatividade , França , História do Século XIX , História do Século XX , Polônio/história , Rádio (Elemento)/história , Urânio/história
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