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101.
在英语学习中动机、满足、兴趣是不能忽视的因素,只有明确自己学英语的动机,通过多方努力感受到学习的满足,产生学习英语浓厚的兴趣,才能真正使英语学习走向高效,走向成功。  相似文献   
102.
This study investigates the influence of policy interests on resource sustainability. Information on ‘colonial interest’ of the British regime and the ‘commercial interest’ of the post-colonial regimes on forest land use of Bangladesh have been drawn on to show the interplay of interests on sustainability impacts. The findings show that both colonial and commercial interests have caused intensification of forest land use for production of economic crops like teak (Tectona grandis) and cash crops like tea (Camellia sinensis), cotton (Gossypium herbaceum and G. arboreum) and tobacco (Nicotiana tabacum). The ‘colonial interest’ has also initiated the dispute of ownership, rights and tenure of forest land and resources. The post-colonial regimes have utilized colonial legacy as the privilege for implementing ‘commercial interests’. In both the cases traditional interests of people were disregarded. As a result, peoples’ participation in forestry was discouraged and the sustainability of forest land use was impeded.  相似文献   
103.
Overwhelming evidence demonstrates the benefits of positive affect for various life and work outcomes. However, the relevant organizational research almost exclusively has focused on general positive affect, thereby implying that all positive affect has consistent and equal relationships with other work variables. The purposes of this theoretical paper are to review and highlight research from basic psychology demonstrating the unique nature and correlates of specific positive emotions and to translate those ideas and findings into the organizational context. Specifically, we discuss three discrete positive emotions—pride, interest, and gratitude—and offer propositions regarding their differential effects on relevant workplace outcomes and regarding the differential antecedents of them. Our hope is that this paper stimulates future research on this topic, and we offer specific research strategies and ideas to facilitate those endeavors. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
104.
Safety Instrumented Systems (SIS) constitute an indispensable element in the process of risk reduction for almost all of nowadays' industrial facilities. The main purpose of this paper is to develop a set of generalized and simplified analytical expressions for two commonly employed metrics to assess the performance of SIS in terms of safety integrity, namely: the Average Probability of Failure on Demand (PFDavg) and the Probability of Dangerous Failure per Hour (PFH). In addition to the capability to treat any K-out-of-N architecture, the proposed formulas can smoothly take into account the contributions of Partial Stroke Testing (PST) and Common Cause Failures (CCF). The validity of the suggested analytical expressions is ensured through various comparisons that are carried out at different stages of their construction.  相似文献   
105.
在系列浓度的敌百虫农药暴露中,鲤鱼脑乙酰胆碱酯酶(Acetyl-cholinesterase,AChE)和鳃?肾腺三磷酶(Adenosinetriphosphatase,ATPase)的敏感性依次为脑AChE>肾ATPase>鳃ATPase?引起死亡的脑AChE抑制率在急性暴露中可大于95%,而鳃?肾ATPase抑制率达50%~60%时,鱼通常难以存活?实验结果表明,AChE抑制并非是有机磷农药中毒中引起死亡的唯一原因,非胆碱能毒性作用也具有重要的作用?   相似文献   
106.
公益诉讼是生物多样性司法保护的重要手段之一。其中,水生动植物资源损害情况、致害因素以及二者之间因果关系的准确判定是确定赔偿并公正判决的基础,对于能否通过诉讼达到修复生态损害、维护生物多样性至关重要。鉴于此,本研究通过梳理、分析474件涉及水生动植物损害的公益诉讼案件判决文书,结合前期学者研究和个别案件探究,从鉴定评估的主体、内容、结果三个方面,评析当前公益诉讼案件中水生动植物资源鉴定评估状况。结果发现,公益诉讼中水生动植物资源的损害评估存在评估主体制度不健全、评估标准和规范不完善、评估结果可靠性欠缺等问题。对于上述问题,应当充分考虑水生动植物资源的特殊性,加强评估主体的制度建设、明确并细化评估标准,及规范并落实评估相关保障制度。  相似文献   
107.
缪颖 《四川环境》2022,(1):240-244
诉前程序与诉讼程序既相互独立,又紧密衔接,在公益诉讼案件中起着督促和过滤的作用.但是目前我国公益诉讼还处在发展初期,行政公益诉讼诉前程序在实践运用中的诸多弊端也逐渐暴露出来:案件线索来源太过单一、行政机关履职标准不明确、检察建议的相关规定不完善等.以行政公益诉讼制度中的诉前程序为研究对象,通过梳理相关法律规定,并结合其...  相似文献   
108.
微波消解-火焰原子吸收光谱法测定芦苇笋中的镉   总被引:11,自引:3,他引:8  
采用密闭微波消解-火焰原子吸收光谱法对洞庭湖区芦苇笋中的镉进行了测定.结果表明,密闭微波消解是一种非常有效的植物样品前处理方法,对国家标准物质灌木枝叶的测定结果与推荐值吻合,表明该方法准确可靠.  相似文献   
109.
Many recent developments in coastal science have gone against the demands of European Union legislation. Coastal dune systems which cover small areas of the earth can host a high level of biodiversity. However, human pressure on coastal zones around the world has increased dramatically in the last 50 years. In addition to direct habitat loss, the rapid extinction of many species that are unique to these systems can be attributed to landscape deterioration through the lack of appropriate management. In this paper, we propose to use of an ecosystem classification technique that integrates potential natural vegetation distribution as a reference framework for coastal dune EU Habitats (92/43) distribution analysis and assessment. As an example, the present study analyses the EU Habitats distribution within a hierarchical ecosystem classification of the coastal dune systems of central Italy. In total, 24 land elements belonging to 8 land units, 5 land facets, 2 land systems and 2 land regions were identified for the coastal dunes of central Italy, based on diagnostic land attributes. In central Italy, coastal dune environments including all the beach area, mobile dunes and all the fixed-dune land elements contain or could potentially hold at least one EU habitat of interest. Almost all dune slack transitions present the potentiality for the spontaneous development of EU woodlands of interest. The precise information concerning these ecosystems distribution and ecological relationships that this method produces, makes it very effective in Natura 2000 European network assessment. This hierarchical ecosystem classification method facilitates the identification of areas to be surveyed and eventually bound, under the implementation of EU Habitat directive (92/43) including areas with highly disturbed coastal dune ecosystems.  相似文献   
110.
耕地转为建设用地能产生高额的土地增值收益,因而建设占用是我国耕地减少的重要因素之一,对建设用地的控制是保持耕地稳定的必不可少的一环.因此,构建了耕地保护经济合理性一般均衡分析理论模型.模型研究表明,为有效控制建设用地对耕地的占用,必须将土地出让收益与种植业收益比保持在一定限度内.山东省典型案例区耕地保护实证表明,在耕地变化驱动因素保持不变、提高5%和降低5%的3种情景下,为保持现有耕地面积不减少、土地增值收益惠及农民、政府(地方政府、省级和中央政府)土地出让收益不受损、土地使用者承担相应耕地保护责任,典型案例区单位面积土地出让收益与种植业收益比年变化率至少应保持在1.09%-8.75%之间;单位面积土地出让收益与粮食收益比年变化率应至少保持在4.24%-10.78%之间.上述结果可以为我国耕地保护政策的制定提供参考.  相似文献   
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