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| Registros recuperados: 1.973 | |
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| Corliss, J B; Baross, Ja; Hoffman, Se. |
| A diverse set of observations from Archaean fossil-bearing rocks, modern submarine hydrothermal systems, experimental and theoretical work on the abiotic synthesis of organic molecules and primitive organized structures, and on water-rock interactions suggests that submarine hot springs were the site for the synthesis of organic compounds leading to the first living organisms on earth. These systems are characterized by high fluxes of thermal energy, highly reducing conditions, abundant and appropriate catalytic surface areas (Fe-Mg clay minerals), significant concentrations of CH sub(4), NH sub(3), H sub(2), metals, etc., and a continuous convective flow which removes products from the site of reaction upward through a mixing gradient of temperature and... |
| Tipo: Text |
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| Ano: 1981 |
URL: http://archimer.ifremer.fr/doc/00245/35661/34170.pdf |
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| Ramaratnam, S. Sri. |
| Static economic theory views the production and consumption sides of the economic environment separately as two unique activities. The distinction between the business and home aspects in the case of farming arose in economic theory and principles of analysis, especially because static theory assumes perfect knowledge, perfect foresight and the absence of change in production techniques and consumption patterns, and overlooks their interrelationships and interdependence when farmers are viewed both as producers and consumers. A great number of personal values, wants, and desires are encountered on the production side of farming and a major part of management consists of appraising the subjective costs and values of performing the various managerial... |
| Tipo: Thesis or Dissertation |
Palavras-chave: Farm Management. |
| Ano: 1981 |
URL: http://purl.umn.edu/11250 |
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| Loureiro,Arthur A.; Vasconcelos,Francisco José de; Albuquerque,Byron W. P. de. |
| Resumo No presente trabalho, os autores apresentam o estudo dos caracteres anatômicos das madeiras de 4 espécies do gênero Zanthoxylum (Rutaceae) e, para cada uma delas, são apresentadas informações sobre: a) a árvore: descrição botânica, dispersão geográfica, habitat, fenologia e nomes vulgares; b) a madeira: caractersticas gerais, descrição microscópica, usos comuns, 8 microfotografias do lenho das espécies estudadas, 4 pranchas esquemáticas contendo as diversas formas dos elementos vasculares e um quadro apresentando as principais características e diferenças anatômicas das espécies. As espécies estudadas foram: Zanthoxylum compactum (Huber ex Albuquerque) Albuquerque. Z. dellomei (de Albuquerque) Waterman, Z. machadoi (de Albuquerque) Albuquerque e Z.... |
| Ano: 1981 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59671981000800809 |
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| Registros recuperados: 1.973 | |
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