990 resultados para 320.5390
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萨瓦亚尔顿金矿床是我国90年代金矿地质工作者在新疆西南天山地区寻找穆龙套型金矿床的一个突破。本文通过对新疆萨瓦亚尔顿金矿床的矿石矿物组成、稀土元素地球化学、同位素地球化学以及流体包裹体特征等方面的研究,探讨了萨瓦亚尔顿金矿床地质地球化学特征、金的赋存状态及成矿流体特征、成矿流体来源,提出了该矿床的成矿机制,取得如下认识:1.流体包裹体岩相学研究表明,萨瓦亚尔顿金矿床的流体包裹体主要为V+L相和富CO_2相包裹体,前者为NaCl-H_2O体系,后者主要有L_(CO2)、L_(CO2)+L、V_(CO2)+L、V_(CO2)+L_(CO2)+L相包裹体;并发现极少量含子晶流体包裹体。2.通过流体包裹体显微测温学研究,表明金矿床的均一温度成矿早阶段为270~320 ℃,成矿主阶段为170~250 ℃,成矿晚阶段为110-250 ℃,呈逐渐降低的趋势,低温成矿作用明显。3.单个流体包裹体的激光拉曼分析表明,流体包裹体中除含有CO2之外,还含有一定量的N_2和CH_4。4.成矿物质来源的复杂性。萨瓦亚尔顿金矿床矿石中微量元素组成、稀土配分模式大都反映了成矿金属物质主要来自赋矿地层本身。金属硫化物的6345:-3.4‰~+2.6‰,西南天山地区下古生界地层中广泛存在各类火山岩可能是该矿床的主要硫源,部分可能有深部物质的参与。矿石中主要脉石矿物石英和菱铁矿 中包裹体水的氢氧同位素组成为δD = -72%~-62‰,δ~(18)O = -11.6‰~+5.4‰。成矿流体主要为大气降水补给的地下卤水,并有少量岩浆水的混合。5.Ar-Ar同位素地球化学研究表明,萨瓦亚尔顿金矿床的主要成矿时代为印支晚期,210 Ma。6. 对矿石中的流体包裹体进行了温度、压力、成分、pH、含盐度等的分要的,并系统的进行了矿床形成时的物理化学条件的理论计算,基中包括EH、PH、f_(O_2)、f_(S_2)等及金在矿液运移中的搬运形式。指出减压过程或伴生沸腾的减压过程,是矿床形成过程中矿质卸载的基本机制,此外,酸蚀变过程(如绢云母化等)中由于H~+的消耗促进了溶液中pH值的升高;含高炭质的围岩,降低了矿液的氧逸度以及含矿热液与地表下渗冷水的混合等诸多因素,则是矿订形成的辅助机制。
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Chitosan of 24% degree of acetylation was depolymerized by a mixture of cellulase, alpha amylase, and proteinase to give the title oligosaccharides. The removal of products by membrane separation permitted yield maximization of products having degree of polymerization in the 3-10 range. (C) 1999 Elsevier Science Ltd. All rights reserved.
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Características gerais da rede de ensaios de avaliação de genótipos de girassol. Resultados dos ensaios finais de primeiro e de segundo ando ? safra 2008/2009 e safrinha 2009. Ensaio final de segundo ano ? safra 2008/2009. Ensaio final de primeiro ano ? safra 2008/2009. Ensaio final de segundo ano - safrinha 2008. Ensaio final de primeiro ano ? safrinha 2008.
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The heat capacities (C-p) of five types of gasohol (50 wt % ethanol and 50 wt % unleaded gasoline 93(#) (E50), 60 wt % ethanol and 40 wt % unleaded gasoline 93(#) (E60), 70 wt % ethanol and 30 wt % unleaded gasoline 93(#) (E70), 80 wt % ethanol and 20 wt % unleaded gasoline 93(#) (E80), and 90 wt % ethanol and 10 wt % unleaded gasoline 93(#) (E90), where the "93" denotes the octane number) were measured by adiabatic calorimetry in the temperature range of 78-320 K. A glass transition was observed at 95.61, 96.14, 96.56, 96.84, and 97.08 K for samples from the E50, E60, E70, E80, and E90 systems, respectively. A liquid-solid phase transition and a solid-liquid phase transition were observed in the respective temperature ranges of 118-153 and 155-163 K for E50, 117-150 and 151-164 K for E60, 115-154 and 154-166 K for E70, 113-152 and 152-167 K for E80, and 112-151 and 1581-167 K for E90. The polynomial equations of Cp and the excess heat capacities (C-p(E)), with respect to the thermodynamic temperature, were established through least-squares fitting. Based on the thermodynamic relationship and the equations obtained, the thermodynamic functions and the excess thermodynamic functions of the five gasohol samples were derived.
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Background Increasing prevalence of overweight and obesity represents a global pandemic. As the largest occupational group in international healthcare systems nurses are at the forefront of health promotion to address this pandemic. However, nurses own health behaviours are known to influence the extent to which they engage in health promotion and the public's confidence in advice offered. Estimating the prevalence of overweight and obesity among nurses is therefore important. However, to date, prevalence estimates have been based on non-representative samples and internationally no studies have compared prevalence of overweight and obesity among nurses to other healthcare professionals using representative data. Objectives To estimate overweight and obesity prevalence among nurses in Scotland, and compare to other healthcare professionals and those working in non-heath related occupations. Design Cross-sectional study using a nationally representative sample of five aggregated annual rounds (2008-2012) of the Scottish Health Survey. Setting Scotland. Participants: 13,483 adults aged 17 to 65 indicating they had worked in the past 4 weeks, classified in four occupational groups: nurses (n = 411), other healthcare professionals (n = 320), unqualified care staff (n = 685), and individuals employed in non-health related occupations (n = 12,067). Main outcome measures: Prevalence of overweight and obesity defined as Body Mass Index ≥ 25.0. Methods Estimates of overweight and obesity prevalence in each occupational group were calculated with 95% confidence intervals (CI). A logistic regression model was then built to compare the odds of being overweight or obese with not being overweight or obese for nurses in comparison to the other occupational categories. Data were analysed using SAS 9.1.3. Results 69.1% (95% CI 64.6,73.6) of Scottish nurses were overweight or obese. Prevalence of overweight and obesity was higher in nurses than other healthcare professionals (51.3%, CI 45.8,56.7), unqualified care staff (68.5%, CI 65.0,72.0) and those in non-health related occupations (68.9%, CI 68.1,69.7). A logistic regression model adjusted for socio-demographic composition indicated that, compared to nurses, the odds of being overweight or obese was statistically significantly lower for other healthcare professionals (Odds Ratio [OR] 0.45, CI 0.33,0.61) and those in non-health related occupations (OR 0.78, CI 0.62,0.97). Conclusions Prevalence of overweight and obesity among Scottish nurses is worryingly high, and significantly higher than those in other healthcare professionals and non-health related occupations. High prevalence of overweight and obesity potentially harms nurses’ own health and hampers the effectiveness of nurses’ health promotion role. Interventions are therefore urgently required to address overweight and obesity among the Scottish nursing workforce.
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Oxtoby, B.; McGuinness, T.; and Morgan, R. (2002). Developing organisational change capability. European Management Journal. 20(3), pp.310-320 RAE2008
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uma revisão sobre alguns estudos epidemiológicos melhorará a compreensão quanto aos efeitos potenciais na saúde da gestão de resíduos e permitirá obter informação importante em termos de trabalho futuro. Alguns estudos mostraram associações significativas entre diversos métodos de gestão de resíduos e impactos potenciais na saúde humana. noutros estudos as associações foram consideradas inconsistentes ou susceptíveis de conduzir a equívocos, sendo necessários mais estudos epidemiológicos para averiguar as consequências para a saúde humana e para determinar os seus efeitos toxicológicos directos, assegurando assim que a gestão de resíduos representa um risco mínimo para a saúde. os estudos epidemiológicos devem ser analisados com uma mente aberta, tomando em consideração factores como o estatuto social e a migração das populações. A review of a few epidemiologic studies will improve the understanding of the potential health effects of waste management and will provide important information regarding future work. several studies showed significant relationships between several methods of waste management and potential impacts on human health. in other studies associations were found to be inconsistent or equivocal and more specific epidemiological studies must be performed to assess consequences to human health and to determine their direct toxicological effects, thus ensuring that waste management pose minimum risk to health.
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18 hojas : ilustraciones, fotografías a color.