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401.
中国目前存在着大量的环境犯罪行为,但对环境犯罪的追究力度不够。许多国家将违反环保部门决定的行为直接规定为犯罪,这种做法体现了环境刑法的行政从属性特征,有利于对环境犯罪行为的判断,可以强化环保部门的环境保护作用,对环境保护起到预防作用。中国应借鉴这些做法,在立法上加以明确的规定,并重视相关问题的研究。  相似文献   
402.
The impact of the extreme heat wave that affected Melbourne, Australia, in two distinct phases in January and February 2009 was severe, with 374 (heat) and 173 (bushfire) excess deaths. Whilst the human health issues have been covered in detail in policy and academic arenas, much less attention has been paid to the adverse impacts on urban infrastructure. Analysis of this event, underpinned by participatory actor-based research, has shown that the impacts were experienced disproportionately across different infrastructure types. For water, telecommunications and airports, the impacts were relatively minor and the impact on rail transport and roads (and to a lesser extent, seaports) was of moderate significance, whereas research findings indicate that the electricity sector was found to be the most vulnerable. This paper focuses on the sectors that were worst impacted: electricity, rail and road transport. Commentary identifies the direct and indirect impacts of the heat event, including associated cascading effects, as well as considering actual and potential adaptation responses both before and after the event. Concluding, the authors reflect on the implications of the heat wave for urban resilience, emphasising the crucial importance of understanding the urban environment as a complex and interconnected system.  相似文献   
403.
This article focuses on the everyday life of ordinary households, their behaviour and responsibility with regard to environmental and sustainability issues. Previous research has shown that there is a gap between what households perceive as ideologically correct behaviour and what they actually do. It is argued here that socio-cultural dispositions, material culture and collective action need to be included in future strategies for creating more sustainable lifestyles. The investigation is based on a study of families participating in a year-long project in which the families learned to live in a more environmentally friendly way. In the study of the families, material culture interacted with routines, family relations and citizenship in a reproducing manner. The lifestyle changes were gender-biased, with the women as driving forces but also bearing most of the extra workload. From early life experiences, garbage sorting stood out as an especially powerful tool for a change towards more sustainable lifestyles.  相似文献   
404.
建筑物人员疏散行动时间的预测研究   总被引:12,自引:6,他引:6  
针对目前疏散模型忽略房间中障碍物对人员行动的影响,笔者提出一种“L型”行动路线,并对空间节点进行了细化,根据网络控制型原理,建立了更为完善合理的疏散行动时间预测数学模型。在该研究的基础上,开发出了高层建筑人员疏散行动时间预测软件,该软件具有计算速度快、动态模拟性强的特点。通过实例计算对比国外公式,证明了节点细化的正确性和开发软件的适用性及可靠性。  相似文献   
405.
Abstract

Microbes are sources of a diverse array of phytotoxic compounds. These compounds are generally structurally different from commercial herbicides, targeting different molecular sites of action within the plant. These novel structures and sites can be excellent leads for the discovery and development of safer synthetic herbicides. Microbial phytotoxins are often more environmentally benign than synthetic herbicides. Examples of phytotoxins from fungi (AAL‐toxin, cornexistin, cyperin, and tentoxin) with novel structures and sites of action are discussed. AAL‐toxin is toxic to a wide variety of weeds at very low dose rates. AAL‐toxin and many of its analogues kill plants by inhibiting a ceramide synthase‐like enzyme, causing rapid accumulation of free sphingoid bases that disrupt membranes. Cornexistin appears to be metabolically cnverted to an inhibitor of certain aspartate amino transferase isoenzymes. Its activity can be reversed by feeding aspartate and glutamate or with tricarboxylic acid cycle intermediates. Its activity is much like that of (aminooxy)acetate. Cyperin is a diphenylether phytotoxin that inhibits protoporphyrinogen oxidase, but does not kill plants by this mechanism. It appears to have other effects on porphyrin metabolism. Tentoxin is toxic by two mechanisms. It disrupts chloroplast development by inhibiting the processing of a nuclear‐coded plastid protein, and it also inhibits photophosphorylation by acting as an energy transfer inhibitor of coupling factor 1 ATPase. Other examples of phytotoxins from microbes with promise as herbicides will be mentioned.  相似文献   
406.
目的 精确描述压缩橡胶永久变形率的变化规律,准确评估其使用寿命。方法 应用环境作用动力学理论,建立压缩橡胶永久变形率的变化微分方程,求解微分方程得到压缩橡胶永久变形率变化规律的微分方程通解。再以氟硅橡胶为例,通过高温加速试验获取其在100、125、150、175、200℃下的试验数据,分别采用环境作用动力学通解和阿伦尼乌兹公式建立氟硅橡胶压缩永久变形率模型。最后,与3.5 a的自然环境试验数据进行对比。结果 应用环境作用动力学理论建立的氟硅橡胶压缩永久变形率模型与3.5 a自然环境试验数据的最大误差约为3.32%,而应用阿伦尼乌兹公式建立的氟硅橡胶压缩永久变形率模型的最大误差约为14%。结论 阿伦尼乌兹公式只适用于没有环境作用或固定环境作用下的物质特征变化,而环境作用动力学方程中,有明确的环境作用项σ,适用于复杂环境作用下物质特征变化规律的描述。  相似文献   
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