932 resultados para Jequitinhonha, Francisco Gê Acaiaba de Montesuma, Visconde de, 1794-1870


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This series will include all those people who, by means of their contributions, great and small, played a part in the consolidation of ichthyology in Argentina. The general plan of this work consists of individual factsheets containing a list of works by each author, along with reference bibliography and, whenever possible, personal pictures and additional material. The datasheets will be published primarily in chronological order, although this is subject to change by the availability of materials for successive editions. This work represents another approach for the recovery and revalorization of those who set the foundations of Argentine ichthyology while in diverse historical circumstances. I expect this to be the beginning of a major work that achieves the description of such a significant part of the history of natural sciences in Argentina.

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G-M制冷机是回热式的小型低温制冷机,它利用绝热放气膨胀原理(又称为西蒙膨胀法)获得低温,具有振动小、运行稳定、寿命长、操作方便等特点,在对效率、重量、尺寸等没有太高要求的场合应用非常广泛。在八十年代末,G-M制冷机已经突破了液氦温度,非常适合在液氦温区为超导器件或电子元件提供冷量,在低温真空泵、MRI超导磁体冷却系统、SQUID再冷凝系统等方面有良好的应用前景,推广其应用已属当务之急。本文围绕着探索氦温区G-M制冷机工作机理、提高低温蓄冷器性能及新型结构G-M制冷机的研制等方面,进行了系统地理论分析和纳归纳,以及初步地实验研究:一. 首次比较完善地建立了液氦温区G-M型制冷机整机数值模拟方法,数值模拟方法给出了制冷机内工质参数瞬态分布及动态变化曲线,为分析制冷机独特的循环特性提供了直观的依据,为探讨运行及结构参数对制冷性能的影响机理提供了强有力的工具。模型中考虑了制冷机中的阻力、实际进排气角、物性变化及蓄冷器内空隙率的存在等多种实际因素:解决了一、二级耦合及部件交界处物性变化不连续对计算影响等问题;采取网格非均匀化、牛顿迭代法以及负反馈原理等措施,提高了计算精度和收敛性。在微机上成功地模拟了液氦温区G-M制冷机的工作过程,程序采用模块化编程,具有一定通用性。二. 运用液氦温区整套机数值模拟方法,计算了制冷机内工质参数(氦流温度、压力、流速等)周期性变化和空间分布,采用一级蓄冷器与低温蓄冷器工作特性对比法,从整机内工质参数动态变化规律分析的角度,验证了液氦温区G-M制冷机工质氦的循环主要分为两部分:常规循环、低温循环。并详细地讨论了运行参数(频率、工作压力)及一级制冷机结构参数对整机内工数动态变化的影响规律以及制冷机性能的影响机理。三. 首次建立了较完善的液氦温区多层混合填料型低温蓄冷器的数值模拟方法,运用数值模拟方法,首次详细地研究了常用填料的不同组合、一定组合下填料比例以及蓄冷器结构对制冷机性能的影响机理,提出了不同填料的最佳节组合及一定组合下填料最佳比例的确定和低温蓄冷器结构和填料优化的原则,为合理有效地设计高性能液氦温区低温蓄冷器提供了依据。四. 提出并设计、加工了一种新型结构的液氦温区双级G-M型制冷机,该机结构在国内外属于首创。其具有以下主要结构特点:一、二级分别独立驱动;一、二级之间通过热桥连接;二级蓄冷器外置于汽缸等。同时建立了新型结构液氦温区双级G-M型制冷机实验系统,为今后整机性能和内部动态过程的研究奠定了基础。五. 新型结构双级G-M型制冷机二级单机动转频率为0.6Hz时,制冷温度为13.6K,且在20K时有4.4W的制冷量;制冷机已达到液氦温区,f = 0.4Hz时,最低温度为4.6K;f = 1Hz,制冷温度为10K时,制冷量大于6W,上述结果目前均未见有文献报道。在新型G-M制冷机上,初步进行了低温蓄冷器性能测试实验及运行参数对制冷机性能影响的实验研究。

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1 tarjeta y 1 carta (manuscritas y mecanografiadas) ; entre 146x92mm y 135x215mm. Ubicación: Caja 1 - Carpeta 31

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12 cartas y 2 notas (manuscritas) ; entre 160x215mm y 240x350mm. Ubicación: Caja 1 - Carpeta 41

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12 cartas (manuscritas) ; entre 215x230mm y 210x2970mm. Ubicación: Caja 1 - Carpeta 41

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Francisco Manuel de Melo nasceu em Lisboa, em 23 de novembro de 1608, e morreu na sua quinta em Alcântara, em 13 de outubro de 1966. Estudou no colégio jesuíta, especializando-se em Filosofia e Teologia. Aos dezessete anos, decidiu seguir carreira militar. Condenado por instigar homicídio, esteve preso por onze anos, e, em 1655, foi degredado para o Brasil, para onde partiu na armada de Francisco de Brito Freire. Retornou a Portugal em 1658. De lá foi para a Itália, onde permaneceu por alguns anos e começou, em 1664, a fazer uma edição completa de suas obras, às quais, por motivo ignorado, não deu continuidade. Transferiu-se para Lisboa, onde, logo depois, veio a falecer. Historiador, poeta, orador e crítico-moralista, Francisco Manuel foi um dos escritores mais eruditos e polidos.

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Background: Budesonide has a long history as intranasal drug, with many marketed products. Efforts should be made to demonstrate the therapeutic equivalence and safety comparability between them. Given that systemic availability significantly varies from formulations, the clinical comparability of diverse products comes to be of clinical interest and a regulatory requirement. The aim of the present study was to compare the systemic availability, pharmacodynamic effect, and safety of two intranasal budesonide formulations for the treatment of rhinitis. Methods: Eighteen healthy volunteers participated in this randomised, controlled, crossover, clinical trial. On two separated days, subjects received a single dose of 512 mu g budesonide (4 puffs per nostril) from each of the assayed devices (Budesonida nasal 64 (R), Aldo-Union, Spain and Rhinocort 64 (R), AstraZeneca, Spain). Budesonide availability was determined by the measurement of budesonide plasma concentration. The pharmacodynamic effect on the hypothalamic-adrenal axis was evaluated as both plasma and urine cortisol levels. Adverse events were tabulated and described. Budesonide availability between formulations was compared by the calculation of 90% CI intervals of the ratios of the main pharmacokinetic parameters describing budesonide bioavailability. Plasma cortisol concentration-time curves were compared by means of a GLM for Repeated Measures. Urine cortisol excretion between formulations was compared through the Wilcoxon's test. Results: All the enroled volunteers successfully completed the study. Pharmacokinetic parameters were comparable in terms of AUC(t) (2.6 +/- 1.5 vs 2.2 +/- 0.7), AUCi (2.9 +/- 1.5 vs 2.4 +/- 0.7), t(max) (0.4 +/- 0.1 vs 0.4 +/- 0.2), C(max)/AUC(i) (0.3 +/- 0.1 vs 0.3 +/- 0.0), and MRT (5.0 +/- 1.4 vs 4.5 +/- 0.6), but not in the case of C(max) (0.9 +/- 0.3 vs 0.7 +/- 0.2) and t(1/2) (3.7 +/- 1.8 vs 2.9 +/- 0.4). The pharmacodynamic effects, measured as the effect over plasma and urine cortisol, were also comparables between both formulations. No severe adverse events were reported and tolerance was comparable between formulations. Conclusion: The systemic availability of intranasal budesonide was comparable for both formulations in terms of most pharmacokinetic parameters. The pharmacodynamic effect on hypothalamic-pituitary-adrenal axis was also similar. Side effects were scarce and equivalent between the two products. This methodology to compare different budesonide-containing devices is reliable and easy to perform, and should be recommended for similar products intented to be marketed or already on the market.

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Hybrids of Clariid catfishes; C. gariepinus (Netherlands), C. anguillaris, H. bidorsalis and their parental species were monitored for 8 weeks in 2 x 2 x 1m outdoor concrete tanks. The fry were fed NIFFR diet (40% crude protein) twice daily, 7 days of the week. Growth and survival records were taken weekly. The male HEB X female CLG hybrid showed an overall highest performance in growth rate while the lowest was recorded in male CLA X female CLG hybrid. The male HEB X female CLG hybrid grew at a faster rate than its reciprocal hybrid. In view or their growth rate, it is possible that the growth and survival rates or H. bidorsalis especially at the fry to fingerling stage could be improved through hybridization. The hybrid have potential as commercial food fish

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The San Francisco Bay Conservation and Development Commission (BCDC), in continued partnership with the San Francisco Bay Long Term Management Strategies (LTMS) Agencies, is undertaking the development of a Regional Sediment Management Plan for the San Francisco Bay estuary and its watershed (estuary). Regional sediment management (RSM) is the integrated management of littoral, estuarine, and riverine sediments to achieve balanced and sustainable solutions to sediment related needs. Regional sediment management recognizes sediment as a resource. Sediment processes are important components of coastal and riverine systems that are integral to environmental and economic vitality. It relies on the context of the sediment system and forecasting the long-range effects of management actions when making local project decisions. In the San Francisco Bay estuary, the sediment system includes the Sacramento and San Joaquin delta, the bay, its local tributaries and the near shore coastal littoral cell. Sediment flows from the top of the watershed, much like water, to the coast, passing through rivers, marshes, and embayments on its way to the ocean. Like water, sediment is vital to these habitats and their inhabitants, providing nutrients and the building material for the habitat itself. When sediment erodes excessively or is impounded behind structures, the sediment system becomes imbalanced, and rivers become clogged or conversely, shorelines, wetlands and subtidal habitats erode. The sediment system continues to change in response both to natural processes and human activities such as climate change and shoreline development. Human activities that influence the sediment system include flood protection programs, watershed management, navigational dredging, aggregate mining, shoreline development, terrestrial, riverine, wetland, and subtidal habitat restoration, and beach nourishment. As observed by recent scientific analysis, the San Francisco Bay estuary system is changing from one that was sediment rich to one that is erosional. Such changes, in conjunction with increasing sea level rise due to climate change, require that the estuary sediment and sediment transport system be managed as a single unit. To better manage the system, its components, and human uses of the system, additional research and knowledge of the system is needed. Fortunately, new sediment science and modeling tools provide opportunities for a vastly improved understanding of the sediment system, predictive capabilities and analysis of potential individual and cumulative impacts of projects. As science informs management decisions, human activities and management strategies may need to be modified to protect and provide for existing and future infrastructure and ecosystem needs. (PDF contains 3 pages)

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A preliminary survey was conducted among the fishermen in five selected villages in Edozhigi L.G.A. of Niger State. One hundred and fifty fishermen were randomly selected and interviewed to find out the impact of Niger State fisheries legislation on fisheries conservation resources in the area. The analysis of data collected using descriptive statistics indicated that undersized mesh of gill nets, beach seines and traps are being used unabated. Also, fenced barriers across the entrance of flood plain ponds and Ex-bow lakes from the main stream are in the area. The fisheries rules and regulations implementers are rarely seen or not seen at all in the area. The decreasing nature of fish catches was detected. It is observed that government policy on fish conversation is neglected due to inadequate or lack of funding for meaningful extension and implementation of the fisheries rules and regulations