988 resultados para 174-1073


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When examined in their sedimentologic and stratigraphic context, ichnofabrics and component ichnofossils can help decipher paleoceanography and sea-level histories from marine deposits (Savrda, 1995, http://www.jstor.org/stable/3515095). Thus far, applications of ichnology in paleoceanographic investigations have been restricted to slowly deposited, predominantly biogenic sediments and/or strata deposited in oxygen-deficient, tectonically active basins. Moreover, ichnologic applications in sequence stratigraphic studies largely have been restricted to strata deposited in relatively shallow-water shelf or foreland basin settings. The limits of previous studies provided impetus for detailed postcruise examination of Quaternary deposits recovered at Ocean Drilling Program (ODP) Site 1073 on the New Jersey margin. These deposits provide the opportunity to assess the sedimentary and ichnofabric record of glacio-eustatic cycles in a passive continental slope setting characterized by relatively rapid accumulation of siliciclastic sediments in an area not far removed from the Laurentide ice margin. The primary purpose of this data report is to present basic sedimentologic and ichnologic observations made at the decimeter scale throughout the Quaternary sequence from Site 1073. Data analysis and interpretation in the context of climate and sea-level histories, as inferred from oxygen isotopic, palynologic, and seismic studies, are ongoing and will be presented in subsequent papers prepared for open literature (e.g., Savrda et al., in press).

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The phase relations in the system Dy–Mg–Cl at 1073 K have been established by isothermal equilibration and chemical analysis of quenched samples. Liquid Mg-rich alloy was found to be in equilibrium with molten DyCl2. Therefore, DyCl2 can be synthesized by reduction of MgCl2 with excess of metallic Dy at 1073 K. The Gibbs energy of formation of DyCl2 at 1073 K was evaluated by two different methods. From voltammetric determination of decomposition voltage, the upper limit for the standard Gibbs energy of formation of DyCl2 was estimated to be −505(±20) kJ mol−1. A value of −543(±10) kJ mol−1 was deduced from phase relations using Gibbs–Duhem integration. The value for the standard Gibbs energy of DyCl2 indicates that the Dy2+ ion has a potential capability for reducing TiCl4 to metal titanium. At the same time, Mg is a reductant for Dy3+ produced during the reduction of TiCl4. Thus, it is thermodynamically confirmed that reduction of TiCl4 by magnesium using a reaction mediator in the salt phase is feasible.

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A Constituinte e as formas de prevenir o agravamento dos problemas das grandes cidades. Deni Schwartz, Ministro do Desenvolvimento Urbano, considera que um dos pontos mais sérios é o da propriedade urbana, que não pode ser tratada da mesma forma que a propriedade rural. O Deputado Manoel Castro (PFL-BA) diz que a Constituição deve obrigar o governo a cuidar da habitação popular. Na Assembleia Nacional Constituinte (ANC) algumas ideias já surgiram, como por exemplo a do usucapião urbano. O Senador Teotônio Vilela Filho (PMDB-AL) considera que a questão urbana está intimamente ligada e dependente a questão agrária. O Deputado Jessé Freire (PFL-RN) quer que a nova Carta garanta instrumentos de planejamento espacial capazes de resolver, como um todo, o problema agrário e urbano. O Deputado Roberto D'Ávila (PDT-RJ) reapresentou duas emendas populares, que não puderam ser aproveitadas por não cumprirem todas as exigências. Uma delas trata da obrigatoriedade de concurso público para ingresso no funcionalismo público. Outra trata de direitos humanos, como a liberdade de credo e direitos dos presos. O Deputado Eraldo Trindade (PFL-AP) apresentou emenda que garante a nacionalização das riquezas minerais. Ivan Lins convoca o povo a participar das emendas populares.

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A Reforma Urbana na Constituição. Atualmente setenta por cento dos brasileiros vivem nos grandes centros enfrentando todos os tipos de privações. João Ricardo Serran, membro do Conselho Nacional de Desenvolvimento Urbano, observa que as cidades estão baixando a qualidade de vida. Deni Schwartz, Ministro do Desenvolvimento Urbano, acredita que a Reforma Urbana é um grande desafio. O Deputado Flávio Palmier da Veiga (PMDB-RJ) apresentou emenda concedendo os benefícios previdenciários para as donas de casa. A Deputada Maria de Lourdes Abadia (PFL-DF) lembra a importância da bancada feminina na Assembleia Nacional Constituinte ( ANC) e também a importância dos movimentos populares nas votações da nova Constituição do Brasil. O Deputado Tito Costa (PMDB-SP) apresentou emenda estabelecendo o mandato sem remuneração para vereadores em municípios de até 300.000 habitantes. O Deputado Victor Fontana (PFL-SC) afirma que a reforma agrária é absolutamente necessária, mas não pode ser feita sem uma política agrícola.

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Viruses, which are characterised by a relative simplicity of chemical composition, are involved with all the groups of the animal and plant world. The discovery of viruses of lower organisms has special interest. Along with the already known viruses lysing bacteria and actinomycetes, viruses have been discovered in recent years which lyse algae. During investigations of water from water-bloom patches and of mud taken from zones of massive accumulation of blue-green algae in the Dneprovsk reservoirs, the authors obtained viruses lysing algae. The revealing of viruses producing lysis of blue-green algae, which one could use in the control of water-blooms, has the greatest interest. With this aim, samples of water were collected from various zones of water-bloom patches in the Kremenchug, Dneprovsk and Kukhov reservoirs. For viruses lysing algae we propose the name 'algophages'. Along with the existence of viruses of algae of the phage type, one cannot deny the possibility of the existence of viruses of another type, multiplying in the cells of algae and causing their virus illnesses.

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Many sides of the biology of Polyphemus pediculus are adequately studied at the present time. Most complicated is the question of its feeding. Dissection does not give an idea of the composition of the food, since Polyphemus strongly grinds its food with its mandibles. For clarification of the composition of the food of Polyphemus pediculus, the authors carried out in July and August 1962 a series of experiments with the application of radio-carbon methods in order to judge the degree of utilization of one or other foods by the quantity of C14, accumulated in the body of the crustacean after feeding. Particular attention in these experiments was given to the question of the possibility of the utilization by polyphemus of plant food - bacteria, algae and detritus.

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Experimental research was conducted to study the development of eggs of Eudiaptomus gracilis Sars. The egg production was studied as well as the population dynamics. Factors like losses in the lake and through the effluent Rhine at Konstanz were considered.