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71.
The accomplishments of inherent safety in the field of loss prevention thus far are impressive due to its scientific philosophy: reducing risks at source rather than adding engineered and procedural protections. Generally, the implementation of inherent safety can be done through a cohesive set of fourteen principles elucidated by Kletz and Amyotte. This work, guided by the fourteen principles, presents a systematic review on the implementation methodologies of inherent safety. Firstly, PRISMA procedure was adopted to select eligible literatures according to inclusive and exclusive criteria. After obtaining the selected literatures, the preference, level of application, and gaps in using these principles were critically analyzed. Of the fourteen principles, intensification, substitution, attenuation, simplification, limitation of effects, and avoidance of knock-on effects are preferable to implementing inherent safety in chemical process. Although the remaining principles are also potentially useful, they are not commonly used due to their costs and complexities of implementation. Overall, this work presents a complete spectrum to look across the implementation methodologies of inherent safety and concludes with some holistic and inclusive approaches as future research recommendations.  相似文献   
72.
The objective of this paper is to discuss the main barriers for modelling and integrating the environmental performances in the automotive concept design. Incorporating environmental assessment in the early design phase of a vehicle component is known as an important challenge that car makers need to face in order to develop more sustainable design solutions; in this regard, the Life Cycle Assessment is the most widespread methodology for the environmental assessment and comparison of alternatives. The present work illustrates the combination of such methodology with the traditional design procedure at two different levels of the component design phase, material choice and concept design. In particular, the potential benefits originated by a lightweight solution for the automotive component Throttle Body are evaluated by considering environmental and technical implications at the same level. The case study shows that a multi-disciplinary approach for design effectively allows the integration of the environmental issue in the company’s established procedures. However, interpretation of results is still a challenging aspect due to the inevitable contradicting elements which should not discourage to develop comprehensive sustainability assessment within the early design stage.  相似文献   
73.
This study investigated the levels, sources and ecological risks of 16 polycyclic aromatic hydrocarbons (PAHs) in two sediment cores that were collected along the Huaxi Reservoir. The spatial distributions and residue levels of the 16 priority PAHs in the sediments from the Huaxi Reservoir were analyzed for their potential ecological risk, source apportionment and contribution to the total PAH residue. The concentration level of the total PAHs (TPAHs) was in the range 1805 ng·g?1 to 20023 ng·g?1 based on dry weight, and the content of PAHs in the Huaxi Reservoir exhibited a gradual upward trend. The PAH congener ratios fluoranthene/(fluoranthene + pyrene) and indeno[1, 2, 3-cd]pyrene/(indeno[1, 2, 3-cd]pyrene + benzo[g, h, i]perylene) were used to identify the source. The main source of the low molecular weight PAHs was wood and coal combustion, whereas the high molecular weight PAHs were primarily from petroleum combustion sources. The results of an ecological risk assessment demonstrated that ACE poses a potential ecological risk, while FLU, NAP, ANT, BaP, DBA, PHEN and PYR can have serious ecological risks.  相似文献   
74.
酶法降解偶氮染料刚果红是一个复杂的过程,受温度、pH、酶量、刚果红浓度和双氧水浓度显著影响。为研究各因素及因素间交互作用对刚果红降解影响,提高刚果红的降解率,分别使用单因素法和响应面分析法对刚果红降解条件进行了优化。单因素实验结果显示灰盖鬼伞过氧化物酶降解刚果红的最适条件为:pH 5.0、32℃、酶量4.98 U、双氧水0.1 mmol/L、刚果红20 mg/L,此时刚果红最高降解率为34.84%。然后选双氧水浓度、刚果红浓度和灰盖鬼伞过氧化物酶量作为3个因素,通过中心组合设计实验,用响应面法对刚果红降解进行优化分析,最后得到一个拟合度良好的二次多项方程模型(R2=0.9900)。方差分析结果显示,刚果红浓度和酶量是影响最显著的因素,双氧水与酶以及染料与酶之间的交互作用极显著。响应面分析优化后的反应体系为:双氧水浓度0.15 mmol/L,刚果红浓度为27.21 mg/L,酶为2.0 7 U,在此条件下,刚果红降解率达58.13%。  相似文献   
75.
从高硫污染的活性污泥中富集培养,分离纯化得到一株可以降解噻吩的菌株s_4,并对该菌株的形态特征进行观察。应用Design—Expert8.0.5b软件进行响应面优化实验,研究了反应时间、噻吩浓度、微生物浓度3个因素的组合对菌株s_4脱硫效果的影响,并拟合得到多元二次回归方程,得出最佳实验条件。拟合结果表明,当反应时间27.46h,噻吩浓度为1.04%,微生物浓度4.04%时,预测噻吩降解率为14.8%,通过验证得最佳条件下的降解率为14.3%,与预测值相符。  相似文献   
76.
对近10 a来国内外有关气候变化经济学研究成果作了综述。气候变化经济学是一门研究人类干预气候变化过程中涉及经济过程的学科。当前的研究热点包括气候变化的经济影响、适应措施的成本和收益、国际合作机制和涉及代际公平的折现率选取。 在研究方法上,对得到广泛运用的成本收益分析法和碳税机制作了详细的评述。在应用层面上,欧美发达国家在城市气候变化经济评估系统建立和碳税征收方面都有成功的应用,但我国在这方面的实践还处于起步阶段。对于我国气候变化经济学领域的研究来说,比较适合在发达省份以市域或省域为单位开展成本收益评估,发展中省份则应将更多关注放在评估气候变化可能造成的经济损害及相应的防范措施。此外,我国也应关注在欧盟地区实施较为成功的碳税政策,虽然目前在中国开征碳税的可能性较低,但是对碳税在中国实施的可行性、税率选取及立法保障机制等方面的探讨和研究仍是必要的  相似文献   
77.
Current methods of estimating potential environmental impacts of metals in hazard and Life Cycle Impact Assessment (LCIA) do not consider differences in chemistry and landscape properties between geographic sites. Here, we developed and applied a model for regional aquatic impact characterization of metals using an updated method for estimating environmental fate factor (FF), bioavailability factor (BF) and aquatic ecotoxicity factor (EF). We applied the model to analyze differences in Comparative Toxicity Potentials (CTPs) of Cu, Ni and Zn for 24 Canadian ecoregions. The combined impacts of regional variability in ambient chemistry (in particular DOC, pH and hardness) and landscape properties (water residence time) can change the CTPs of these metals for freshwater by up to three orders of magnitude and change the relative ranking of metal hazard between ecoregions. Variation among Canadian freshwater chemistries and landscape characteristics influence the FFs within two orders of magnitude, BFs within two orders of magnitude for Ni and Zn and four orders of magnitude for Cu, and EFs within one order of magnitude. Sensitivity of metal FFs to environmental parameters alone spans three orders of magnitude when a constant water chemistry was used for all ecoregions. These results indicate that application of regionalised metal CTPs can have a significant influence in the analysis of ecotoxicological impacts in the life cycle assessment of products and processes.  相似文献   
78.
研究一种新型吸附菌剂Dyella ginsengisoli LA-4(以下简称菌株LA-4)对Cu2+的吸附特性及其动力学,并利用表面响应法优化菌株LA-4对Cu2+的吸附条件.结果表明:(1)菌株LA-4的接种量、pH对Cu2+的吸附有重要的影响.(2)根据表面响应法 优化模型预测出菌株LA-4吸附Cu2+的最...  相似文献   
79.
巢湖流域水质状况与环境目标可达性分析   总被引:10,自引:3,他引:10  
对巢湖湖区、巢湖环湖河流水质现状及变化趋势进行了调查。结果表明。“九五”以来,巢湖湖区水体以劣Ⅴ类为主;2000年以来,巢湖主要环湖河流中,南淝河、十五里河、派河和双桥河入湖常年水质为劣Ⅴ类,其主要污染物为氨氮。巢湖流域水体污染特征为:城市河段污染较重。点源污染较为集中;面源和生活污染贡献较大;从1998年以来,TP与TN质量浓度值一直处于较高水平。巢湖流域水质环境目标可达性分析表明,巢湖湖区整体上尚不能达到规划的目标。到2005年东半湖能稳定达标。南淝河能否实现达标排放。取决于合肥市的污水处理率及处理效果。十五里河、派河、双桥河水质受点源控制,只要加强管理,可达规划的目标。  相似文献   
80.
This research is a combination of gender studies, which highlights differences between men and women, and workplace research, which focuses on the performances that are assumed to affect employee satisfaction. The study proposes a multi-dimensional assessment model that enables consideration of several workplace issues in tandem. Focusing on user satisfaction, the first part of the study is a holistic approach concerned with technical, functional and behavioral variables that provides a broad understanding about gender (in)differences. Personalization, the core issue of the second part of the study, is measured through personal display items, autonomous behavior and office layout preferences of men and women employees. The findings indicate the presence of significant gender differences in terms of satisfaction felt with regard to the behavioral variables. The results also support previous findings indicating that men and women use different personal display items in order to personalize their offices. More women were diagnosed to be changing their room layout on a temporary basis whereas men and women were evidenced for having similar attitudes in making permanent changes and in preferring an office layout for themselves. The findings suggest that gender difference is still a valid subject in workplace research although the differences may not be as sharp as the conventional gender difference myth claims, implying a better understanding of the issues that differently satisfy men and women.  相似文献   
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