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561.
The Clean Development Mechanism (CDM) is one of the flexible instruments of the Kyoto Protocol designed to combat climate change so as to bring advantages to developing countries and developed countries alike. Indeed, CDM projects have a two-fold objective: to offset greenhouse gas emissions and to contribute to sustainable development in the host country. However in many cases, the latter objective appears to be marginalized. This is at least partly due to the difficulties surrounding the definition and the measurement of sustainability, in particular in a developing country context. To assess CDM projects’ contribution to sustainable development in the host country, scholars and practitioners need adapted indicator sets. A set of indicators were developed by way of an iterative Delphi approach amongst selected Vietnamese experts. The Delphi approach allowed a systematic collection of the experts’ judgements on the sustainability indicators through a set of sequentially applied questionnaires, interspersed with feedback from earlier responses. This exercise resulted in the selection of a set of 36 indicators, which emphasise economic efficiency, public health and pollution issues. The exercise yielded a locally supported and context-specific set of sustainability indicators that will allow Vietnamese decision-makers to enhance the sustainability of the approved CDM projects. In the future this set should be continually improved through real-life application and further participation from local stakeholders. This study is a first step in a long-term process towards developing an adapted toolkit for sustainability assessment of CDM projects in Vietnam.  相似文献   
562.
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants that can be present at high levels as mixtures in polluted aquatic environments. Many PAHs are potent mutagens and several are well-known carcinogens. Despite numerous studies on individual compounds, little is known about the toxicity of PAHs mixtures that are encountered in environmental situations. In the present work, zebrafish were continuously fed from 5 days post-fertilisation to 14 months post-fertilisation (mpf) with a diet spiked with fractions of either pyrolytic (PY), petrogenic light oil (LO), or petrogenic heavy oil (HO) origin at three concentrations. A decrease in survival was identified after 3 mpf in fish fed with the highest concentration of HO or LO, but not for PY. All PAH fractions caused preneoplastic and neoplastic disorders in long-term-exposed animals. Target tissues were almost exclusively of epithelial origin, with the bile duct epithelium being the most susceptible to chronic exposure to all PAH fractions, and with germ cells being the second most responsive cells. Significantly higher incidences of neoplasms were observed with increasing PAH concentration and exposure duration. The most severe carcinogenic effects were induced by dietary exposure to HO compared to exposure to LO or PY (45, 30 and 7 %, respectively, after 9 to 10 months of exposure to an intermediate concentration of PAHs). In contrast, earliest carcinogenic effects were detected as soon as 3 mpf after exposure to LO, including the lowest concentration, or to PY. PAH bioactivation and genotoxicity in blood was assessed by ethoxyresorufin-O-deethylase activity quantification and comet and micronuclei assays, respectively, but none of these were positive. Chronic dietary exposure of zebrafish to PAH mixtures results in carcinogenotoxic events that impair survival and physiology of exposed fish.  相似文献   
563.
564.
Mathematical modelling of the oxidation reduction redox potential (ORP) of an electrolyte has been carried out for a batch system comprising an electrochemical reactor and an electrolyte circuit containing a redox couple. The ORP can be useful to monitor the environmental impact of chemical species in solution that represent a risk to the environment. Considerations of four fundamental equations, namely, the Nernst equation, a mass balance, Faraday's laws of electrolysis and a first order kinetic equation, leads to an expression for the electrolyte redox potential as a function of the batch time, the electrical charge and the redox concentration. Such an expression facilitates graphical plots which can be used to estimate kinetic parameters, current efficiency and the relative redox concentration. The Ce(IV)/Ce(III) system has been chosen as a model reaction for electrolyte redox potential measurement in a batch recycle system consisting of a pumped flow through a divided FM01-LC parallel-plate electrochemical reactor (64cm(2) projected electrode area) and a well mixed tank (3600cm(3)). The differences between experimental and model predictions are discussed.  相似文献   
565.
Packing material formulation for odorous emission biofiltration   总被引:1,自引:0,他引:1  
In biological gas treatment, like biofiltration of volatile organic compounds or odorous substances, the microbial nutritional needs could be a key factor of the process. The aim of this work is to propose a new packing material able to provide the lacking nutrients. In the first part of this study, two kinds of material composed of calcium carbonate, an organic binder and two different nitrogen sources, ammonium phosphate and urea phosphate (UP), were compared. The new supports present bulk densities between 0.88 and 1.15g cm(-3), moisture retention capacities close to 50% and 70%, and water cohesion capacities greater than six months for the material with 20% binder. In the second part, oxygen consumption measurements in liquid experiments show that these packing materials could enhance bacterial growth compared to pine bark or pozzolan and have no inhibitory effect. The biodegradation of different substrates (sodium sulfide and ammonia) and the support colonization by the biomass were evaluated. Finally, UP 20 was chosen and tested in a hydrogen sulfide or ammoniac biofiltration process. This showed that, for H2S concentrations greater than 100mg m(-3), UP 20 has a real advantage over pine bark or pozzolan.  相似文献   
566.
567.
横向补偿通常多限于单要素或功能的生态系统服务补偿,如何向调节服务功能贡献区实施多要素综合补偿,仍缺少有效解决方法。本研究基于最大熵增理论本研究提出了“熵增曲面法”,构建调节服务价值扩散的曲面模型。此模型更符合生态系统物质能量流动特点,视调节服务价值为有形的正态分布曲面,曲面动态稳定的扩展状态表达了价值的对外输出。本文以梁子湖流域为例,先利用当量因子法计算出研究区各区的生态调节价值,再用上述方法对区域间调节服务价值补偿问题进行分析,并讨论了考虑环境激励的补偿优化办法。结果显示,研究区内武汉市东湖高新技术开发区(e区)应支付给武汉市江夏区(a区)、鄂州市梁子湖区(b区)、咸宁市咸安区(c区)和大冶市金牛镇(d区),分别为303.8万元、 1866.6万元、 582.4万元、 615.2万元,共3368.0万元。该方法能明确“谁补谁、补什么、补多少”的补偿问题,对邻近区域性的调节服务补偿均可展开分析,为多要素、综合性、系统化的生态补偿方向提供了新的思路。  相似文献   
568.
围绕金属在海洋环境中所面临的腐蚀问题,概述了金属海洋环境腐蚀评估与预测研究现状。首先,探讨了海洋环境中多种化学、物理和生物因素对金属腐蚀的影响,归纳总结了当前常用的金属腐蚀评估方法,涵盖基于试验和检测结果、仿真计算和大数据分析的评估方法。此外,全面综述了现有经验式、基于物理机制以及数据驱动的金属腐蚀预测模型的特点及应用现状,提出了未来金属海洋环境腐蚀评估和预测的研究方向。  相似文献   
569.
大型海啸灾害等自然灾害的发生产生了大量重伤员,所以研究大型海啸灾害后重伤员的批量护理风险建模极为重要.通过大型海啸灾害救治流程预案启动和重伤员批量护理实施方法两部分研究大型海啸灾害后重伤员批量护理方法,并提出通过前馈控制性管理防范护理风险.提升护理风险管理的科学性以及全面性.通过护理风险防范预案提升重伤员护理质量将大型...  相似文献   
570.
<正>The emergence of multidrug-resistant bacteria, or"superbugs," has become an urgent and worldwide concern.Antibiotic-resistant bacteria (ARB) cause significant morbidity and mortality (O'Neill, 2016). It has been estimated that ARB cause at least 23,000 deaths annually in the United States alone and hundreds of thousands of deaths in developing countries (Bougnom and Piddock, 2017). Antibi-  相似文献   
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