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讨论分析了我国野生动物资源现状和《野生动物保护法》制订的历程、实质及贯彻实例的措施。  相似文献   
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复杂人——机系统中的人因失误   总被引:26,自引:12,他引:26  
随着人——机系统变得越来越多,装置的可靠性越来越高,人因失误已成为重要的潜在事故源。本文描述了复杂人——机系统的特征,探讨了该系统中人因失误的定义、分类、数据采集和事故模型。这些研究有助于对人因失误的预测、预防和减少。  相似文献   
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用缺氧生物滤池与UASB相串联的工艺对杭州市天子岭垃圾填埋场惨滤液进行了中试试验。通过实验,总结了缺氧生物滤池的挂膜特性及UASB起动的成功经验。最终的试验结果表明:出水COD、BOD、SS分别稳定在900mg/L、150mg/L、250mg/L以下,缺氧生物滤池对渗滤液具有很好的预处理效果,不仅能脱吸部分NH3、CO2、H2S,而且能提高它的可生化性,为UASB的高效运行创造了良好的条件。  相似文献   
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应用灰色系统理论,根据江苏省地震工程研究院的地震科技开发资料,分别以项目负责人的年龄、学历、职称、职务、学科作为比较数列,对年度内完成的实际合同额进行了多因素灰色关联分析,排出了关联序。研究结果客观地揭示了开发能力与人的各种因素——年龄、学历、职称、职务、学科之间的相互关系,为市场经济条件下,地震科技人才的开发、培养和应用,提供了科学依据。  相似文献   
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Scientific and technological researches are devoted to obtain materials capable of retaining different kinds of pollutants, contributing to contamination solutions. In this context, hydrogels have emerged as great candidates because of their excellent absorption properties as well as good mechanical, thermal and chemical properties. More specifically, ferrogels (magnetic gels) present the extra advantage of being easily manipulated by a permanent magnet. Here, we present the results derived from the application of ferrogels as efficient tools to extract heavy metal pollutants from wastewater samples. The gels were prepared following the method of freezing and thawing of a polyvinyl alcohol aqueous solution with magnetic nanoparticles coated with polyacrylic acid. Ferrogels were fully characterized and their ability to retain Cu2+ and Cd2+, as model heavy metals, was studied. Thus kinetics and mechanisms of adsorption were evaluated and modeled. The concentration of MNPs on the PVA matrix was key to improve the adsorption capability (approximately the double of retention is improved by the MNPs addition). The adsorption kinetics was determined as pseudo-second order model, whereas the Langmuir model was the most appropriate to explain the behavior of the gels. Finally reuse ability was evaluated to determine the real potential of these materials, the ferrogels demonstrated high efficiency up to about five cycles, retaining about 80–90% of their initial adsorption capability. All the results indicated that the materials are promising candidates able to compete with the commercial technology regarding to water remediation.  相似文献   
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In accelerated weathering tests, specimens are exposed to higher radiation intensity, temperature and humidity than is likely under natural weathering in order to achieve rapid degradation of the polymer in a convenient short time. In the current work, a correlation between the two environments is attempted so that a prediction of lifetimes in the natural environment can be achieved. During aging, surface flaws are created due to the chain scission process. This is initiated by the absorption of ultra-violet light and directly affects visual appearance and impact strength. After natural weathering, the material shows only plastic deformation in an impact test. However, after artificial weathering to 5000 h of UV exposure, there is a decrease of 85% in impact strength. Colour change occurs at a high rate in the early stages of UV exposure. Beyond 2000 h of exposure, the colour change approaches a steady state and a correlation between the changes under natural and artificial weathering becomes apparent for a potential prediction of lifetimes. From the analysis including the specular component (SCI), taking surface roughening into account, 1 year under natural weathering was found to be equivalent to 25 days under accelerated weathering.  相似文献   
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There is actually increasing concern about the accumulation of antibiotics, such as tetracycline, in soil and water bodies. There is therefore a need for efficient methods to degrade antibiotics and thus clean waters. Here we tested the degradation of tetracycline using the heterogeneous electro-Fenton-pyrite method and compared the results with the conventional electro-Fenton method. The reaction was performed with a boron-doped diamond or Pt anode and carbon-felt cathode allowing electrogeneration of H2O2 from O2 reduction. Results show an increasing tetracycline mineralization using the following methods: anodic oxidation with electrogenerated H2O2, electro-Fenton and then electro-Fenton-pyrite using boron-doped diamond. Ion-exclusion HPLC revealed the complete removal of malic malonic, succinic, acetic, oxalic and oxamic acids. Nitrogen present in tetracycline was mainly mineralized in NH4 +. The higher efficiency of electro-Fenton-pyrite is explained by self-regulation of soluble Fe2+ and pH to 3.0 from pyrite catalyst favoring larger ·OH generation from Fenton’s reaction.  相似文献   
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The attention to ethics has gradually become a concurrent topic of modern companies’ management. In the last years Social Responsibility has become a key issue in the strategic agenda of competitive agriculture cooperatives. However, reputation management has not been a visible strength in the cooperative enterprises. First of all, this work theoretically analyzes the relationship between Social Responsibility and reputation in cooperatives. Later, from a practical point of view, we carry on an empirical analysis focused on the olive oil cooperatives in the south of Spain, in the province of Jaén. With respect to the previous studies on the topic, this work reveals a main reason of interest reinforcing the role of research in addressing real problems of cooperatives. The article points out the characteristics of this kind of agribusiness and shows the importance of the adoption of a responsible orientation in fostering reputation for creating sustainable competitive advantages.  相似文献   
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