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981.
曝气生物滤池在中水回用中的应用   总被引:1,自引:0,他引:1  
介绍了一种新型曝气生物滤池的工艺原理、结构类型、特征及其在中水回用中的研究进展,探讨了曝气生物滤池技术在中水回用中的应用前景.  相似文献   
982.
Assessments of risk to biodiversity often rely on spatial distributions of species and ecosystems. Range‐size metrics used extensively in these assessments, such as area of occupancy (AOO), are sensitive to measurement scale, prompting proposals to measure them at finer scales or at different scales based on the shape of the distribution or ecological characteristics of the biota. Despite its dominant role in red‐list assessments for decades, appropriate spatial scales of AOO for predicting risks of species’ extinction or ecosystem collapse remain untested and contentious. There are no quantitative evaluations of the scale‐sensitivity of AOO as a predictor of risks, the relationship between optimal AOO scale and threat scale, or the effect of grid uncertainty. We used stochastic simulation models to explore risks to ecosystems and species with clustered, dispersed, and linear distribution patterns subject to regimes of threat events with different frequency and spatial extent. Area of occupancy was an accurate predictor of risk (0.81<|r|<0.98) and performed optimally when measured with grid cells 0.1–1.0 times the largest plausible area threatened by an event. Contrary to previous assertions, estimates of AOO at these relatively coarse scales were better predictors of risk than finer‐scale estimates of AOO (e.g., when measurement cells are <1% of the area of the largest threat). The optimal scale depended on the spatial scales of threats more than the shape or size of biotic distributions. Although we found appreciable potential for grid‐measurement errors, current IUCN guidelines for estimating AOO neutralize geometric uncertainty and incorporate effective scaling procedures for assessing risks posed by landscape‐scale threats to species and ecosystems.  相似文献   
983.
Para-toluene sulfonic acid is a typical intermediary for the synthesis of pharmaceuticals, pesticides, and dyes and is a catalyst for organic synthesis. The consumption of para-toluene sulfonic acid used in organic synthesis has increased substantially. The toluene sulfonation process is the central path for synthesizing para-toluene sulfonic acid in China. However, the process has risks and has resulted in numerous disasters. This study utilized a reaction calorimeter 1 to reproduce the commercial toluene sulfonation process in a laboratory. The para-toluene sulfonic acid product was examined with an accelerating rate calorimeter and through differential scanning calorimetry. Both differential and integral isoconversional methods were used to determine the thermal stability of and appropriate thermokinetic models for para-toluene sulfonic acid. The safety parameters of para-toluene sulfonic acid were estimated. The research findings can be used for optimization of the toluene sulfonation process and for safe handling of para-toluene sulfonic acid.  相似文献   
984.
With the rise of global environmental issues and the emerging trend of corporate social responsibility (CSR) and corporation–non-governmental organization (NGO) alliances, organizations are developing collaborative alliances across sectors and nations to address environment problems. An international perspective is needed to explain the global structure of cross-sector alliance networks and the divergence or similarity of CSR communication across nations. This exploratory study draws insights from the national business systems (NBS) approach and applies social network analysis to examine the cross-sector alliance network among Global 500 Fortune corporations and 441 environmental international NGOs. Findings suggest that (1) an NBS approach to CSR can explain the network structural features of a cross-sector alliance network; (2) political context and national education level strongly predict green partnerships; and (3) regional differences are apparent in the global network, with Asian corporations lagging behind in cross-sector alliance building.  相似文献   
985.
对常规活性污泥法和一体化氧化沟工艺在中原油田基地污水厂的应用效果进行了对比分析。月度抽查对比监测发现,两种生物处理法对有机物均有较好的去除效果。一体化氧化沟工艺是一种新型的生活污水处理技术,它对SS、NH3-N的去除效果优于常规法。连续三天的日均值监测结果表明,新工艺对各种污染物的去除效果达到91%以上。这种工艺集通氧、沉淀、废渣分离和回收为一体,占地面积小,操作简单,在中原油田污水站取得了较好的应用效果。  相似文献   
986.
对四湖地区的农产品资源进行了全面的分析,该地区的农产品优势资源为大米,淡水鱼、牲猪、蔬菜和水生经济作物中的莲藕等。通过对该地区的农产品加工现状进行综合分析,认为农产品的加工增值存在的问题障碍了该地区农业进一步发展,进而提出了相应的措施以及变区域资源优势为地方经济优势的策略。  相似文献   
987.
一体式膜生物反应器污水处理工艺研究   总被引:1,自引:0,他引:1  
在一体式膜生物反应器研制开发实验及反应器各参数运行协调理论分析的基础上,提出了一体式膜生物反应器工艺各参数间的设计原则、方法、步骤及设计实例,对该工艺的运行能耗作了评价.  相似文献   
988.
本文根据层次分析法的原理,结合环境工程评标的特点,建立了评定最优环境工程方案的层次结构模型。该模型引入三标度法来间接地构造判断矩阵,简化了专家或决策者的判断难度,增强了判断矩阵的逻辑性。结合某废水治理工程项目,介绍了层次分析法应用于工程评标的计算过程。结果表明,这种改进的层次分析法是进行环境工程方案优选的新颖、科学、简便的方法。  相似文献   
989.
研究出生物型煤的生产工艺流程,对型煤和生物型煤的固流效果进行了对比。成功地试验生产出固硫性能优良的生物型煤,为消除煤能源利用中的硫污染开辟了新途径。  相似文献   
990.
Process hazards review (PHR) techniques have generally been applied by large, sophisticated companies in the nuclear, aerospace, and chemical process industries. There remains, however, a large population of smaller distributors and consumers of hazardous materials which could benefit equally from the application of PHR. These consumers unfortunately are generally less sophisticated and individually lack the necessary resources required to apply such state-of-the-art safety techniques.

Where common processes can be identified, it is possible to conduct a more generic PHR that will provide a sound technical basis for recognizing and preventing the development of hazards wherever these processes are used. Some facility-specific issues will always need to be considered, but the existence of the generic PHR should make the conduct of a PHR by each facility considerably easier and less costly.

Researchers from the National Institute for Occupational Safety and Health (NIOSH) contracted with DNV Technica Inc. to lead a hazard and operability study (HAZOP) of agricultural handling of anhydrous ammonia, from the receipt of ammonia at the retail distribution centre to the application of the ammonia by farmers to the fields. The multidisciplinary HAZOP team consisted of representatives from NIOSH, an agricultural chemical trade association, an ammonia producer, state ammonia facility inspectors, a retail distributor, and an equipment manufacturer. Several participants were part-time farmers with ammonia application experience.

Some specific aspects of applying the HAZOP technique in the context of this study, the findings obtained, and the plans to disseminate the important safety information developed during the course of the PHR are discussed. Finally, it is suggested that this approach could prove to be a useful addition to the product stewardship activities of chemical producers.  相似文献   

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