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151.
In this paper, an accident analysis model is proposed to develop the cost-efficient safety measures for preventing accidents. The model comprises two parts. In the first part, a quantitative accident analysis model is built by integrating Human Factors Analysis and Classification System (HFACS) with Bayesian Network (BN), which can be utilized to present the corresponding prevention measures. In the second part, the proposed prevention measures are ranked in a cost-effectiveness manner through Best-Fit method and Evidential Reasoning (ER) approach. A case study of vessel collision is analyzed as an illustration. The case study shows that the proposed model can be used to seek out accident causes and rank the derived safety measures from a cost-effectiveness perspective. The proposed model can provide accident investigators with a tool to generate cost-efficient safety intervention strategies.  相似文献   
152.
153.
Burning of crop residues is a common agricultural practice that incorporates the resulting particulate matter (ash) of high adsorptivity into soils. To investigate the effect of ash on the biodegradation of pesticides in soils, we measured the sorption, desorption, and biodegradation of benzonitrile in a silt loam in the presence and absence of an ash resulting from burning of wheat (Triticum aestivum L.) residue. Biodegradation experiments were conducted by inoculating sorbent slurries with a pure culture of benzonitrile-degrading bacteria (Nocardia sp.). Both liquid- and sorbed-phase benzonitrile concentrations were quantified over time. The ash was approximately 2000 times more effective per unit mass than the soil in sorbing benzonitrile. Amendment of the soil with 1% ash (by weight) resulted in a 10-fold increase in sorption. Sorption of benzonitrile by the ash significantly decreased the solution-phase concentration in the slurries of ash and ash-amended soil. Desorption of benzonitrile from the ash required approximately 60 min to complete, whereas approximately 20 min were required for desorption from the soil. Benzonitrile in the extracts of various sorbents and soil slurry was completely degraded within 500 min. However, the degradation was substantially reduced in the presence of the ash. At 2000 min, only 20% of benzonitrile in ash slurry and only 44% in ash-amended soil slurry were degraded. An acclimation period of approximately 100 min was observed in extracts and slurries containing the ash. Substantial reduction in the biodegradation of benzonitrile in the presence of wheat ash was apparently due to sorption of benzonitrile by the ash, slow desorption from the ash, and the increased acclimation period. Our results suggest that the presence of crop-residue-derived ash may increase the persistence of pesticides in agricultural soils.  相似文献   
154.
Reintroduction of wood in rivers for restoration purposes is now recognized in a positive way by scientists. Nevertheless, the perception of wood in riverscapes is strongly affected by the socio-cultural environment. This cultural influence might explain why wood reintroduction is accepted and promoted in some regions of the world but not in others, despite the demonstrated ecological benefits. From an extensive student perception survey, we show that most of the groups from nine countries in the world considered riverscapes with wood to be less aesthetic, more dangerous, and needing more improvement than riverscapes without wood. By contrast, this way of thinking was not observed in Germany, Sweden, and Oregon (USA), where the first instances of wood reintroduction occurred.  相似文献   
155.
农业清洁生产工程体系   总被引:11,自引:0,他引:11  
将工业清洁生产理论移植于农业,通过对农业清洁生产的初步探讨,提出了农业清洁生产工程的工艺体系、技术体系和管理体系,试为农业环境保护和农业生产寻找一条系统的可持续发展之路。  相似文献   
156.
基于《中国植物红皮书》第一、二册名录,重庆有国家重点保护植物77种,隶属于47科,71属。根据第一批公布的国家重点保护植物,重庆有52种49属32科;其中一级5种,二级24种,三级23种,濒危6种,稀有21种,渐危25种。水平分布有三个中心,即大巴山南缘地区、武陵山区、大娄山北缘地区。论文最后提出了珍稀濒危植物的保护措施。  相似文献   
157.
模拟试验表明,氨基酸厂废水可以在一定程度上促进旱坡地紫色土某些生态因子的改善,主要表现在该废水可以增加土壤氮素和有机质含量,改善土壤水分状况,降低土壤失水速率和极限失水率,但也存在氯、盐分的累积,以及铜、锌、锰、铅等重金属元素活性加强等危险,这些结果已从现场调查及采样分析中得到验证。  相似文献   
158.
土壤净化功能的原理及其利用   总被引:6,自引:0,他引:6  
陈玉成 《四川环境》1994,13(4):60-64
本文通过对土地处理系统的剖析,从土壤去除有机物,悬浮物,氮,磷,汞量重金属,病原散生物,污染空气。以及对酸性沉降物的缓冲等诸方面,讨论了土壤净化功能的原理,概括了土壤净化过程,既包括物理的,化学的和生物的作用,又包括物理化学,生物化学的作用,为更好地研究,利用和管理土地处理系统,充分发挥土壤的净化功能提供研究的方向。  相似文献   
159.
针对直接投放CuSO4灭藻易致水体Cu2+局部偏高的事实,以壳聚糖作载体合成缓释性的壳聚糖载铜灭藻剂(Copper-Chitosan Algaecide,CCA),研究其对蛋白核小球藻的灭藻效应.结果表明,CCA能有效控制蛋白核小球藻的生长,其最佳施用时间为蛋白核小球藻的迟缓期,且随着灭藻剂用量增加,灭藻率增大.对于富...  相似文献   
160.
利用碘离子选择电极,以0.1mol/LKNO(3^-)0.01mol/L酒石酸为总离子强度调节荆、Na2SO3为还原保护剂,将加碘食盐中的10(3^-)还原为I^-,在双液接饱和甘汞电极为参比电极的条件下,采用直接电位法和标准曲线法直接测定了溶液中的碘含量,实验结果表明,本方法线性范围10^(-1)~10^(-7)mol/L,检测下限4.6×10^(-8)mol/L,样品具有较好的回收率(98.2%-100.7%),可以用此方法测定食盐中I^-的含量。  相似文献   
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