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301.
模糊综合评价法在乐安河水质评价中的应用   总被引:13,自引:0,他引:13  
根据模糊数学的原理,建立了地表水环境质量模糊综合评价模型,模型不仅计算简便而且充分体现了其系统性、综合性的特点。利用建立的模型对江西省重点整治的河流乐安河进行了水质评价,为污染控制提供了科学依据。  相似文献   
302.
侯筠 《环境科学》1991,12(4):90-93
本课题对模拟废水中RDX在紫外光和氧化剂等作用下的光化学降解情况进行了研究.运用正交设计法来安排实验,获得了废水的酸碱度、过氧化氢与亚铁离子的投加量、紫外光照射的时间等RDX降解的最佳条件.自行设计了光化学降解装置.在最佳条件下对RDX模拟废水进行光化学处理,并利用721分光光度计以及TOC-500测试仪对实验结果进行鉴定,取得了较为满意的结果.  相似文献   
303.
二氧化钛薄膜光催化性能的影响因素及提高途径   总被引:16,自引:0,他引:16  
TiO2薄膜光催化技术有广阔的应用前景,在国内外得到了广泛的研究。介绍了TiO2薄膜光催化降解的研究现状,指出了影响薄膜光催化性能的若干因素和提高薄膜光催化效率的相应手段。另外,对金属复合、半导体复合对TiO2薄膜光催化性能的影响和可见光催化的研究现状进行了评述。  相似文献   
304.
烷烃条件下CF2ClBr的紫外光解离机理研究   总被引:2,自引:0,他引:2  
以气相色谱、红外光谱为主要分析手段,对气态CF2ClBr在CR2ClBr-C6H12体系中的紫外光解离进行了研究,结果表明,在253.7nm紫外光照射下,该体系的主要光解产物为HCVF2Cl、HBr以及C6H12的聚合物,体系中CF2ClBr的解离近似精同缀反应,解离反应的速率常数为2.877×10^-6s^-1表观量子产率约0.1,基于此,对该光解反应的机理做了分析。  相似文献   
305.
ABSTRACT: Flood control operations are generally complex in nature, as they are often associated with a large quantity of uncertain factors in combination of noncommensurable criteria. It has been found that the use of fuzzy set theory coupled with multicriterion decision making (MCDM) methods is very promising. In this paper, a multicriterion fuzzy recognition model is established for flood control operations. A subjective preference and iterative weights method is proposed for weight assessment. First, an initial solution of criteria weights, which is directly analyzed from the selected alternatives, is obtained by using the proposed fuzzy recognition model. Then, according to their knowledge related to real time flood operations, operators may modify the initial weights if necessary. When the relative membership grades of alternatives belonging to all rankings are fixed, a defuzzification equation is used to calculate the rank feature value vector. Based on the rank feature value vector, one can evaluate the alternative set. Two flood operation cases are provided to illustrate the application of the proposed model. With the incorporation of the operator's knowledge related to flood operations, the proposed model is flexible in giving weights and realizes more practical flood control operations.  相似文献   
306.
Environmental Science and Pollution Research - Emerging economies are experiencing considerable economic changes due to change in energy demand and CO2 emissions. To explore the link between energy...  相似文献   
307.
Environmental Science and Pollution Research - Detailed urban drainage data are important for urban nonpoint source (NPS) pollution prediction. However, the difficulties in collecting complete...  相似文献   
308.
ABSTRACT

Aiming at backfill with crack under the thermo-mechanical (TM) coupling, the concepts of crack macro-damage, loading meso-damage, thermal meso-damage, and total damage of backfill were proposed. Based on the statistical damage theory, considering the coupling effects of temperature, load and initial crack, a damage evolution model of backfill with crack under TM coupling effects was established. Based on this, the strength criterion of backfill with crack considering the effects of thermal and mechanical coupling was constructed by multivariate function full differential method. The research shows that: (1) The theoretical curves of damage evolution model and strength criterion of backfill with crack under TM coupling are in good agreement with the test curves, which verifies the rationality of the model. (2) The initial thermal damage decreases first and then increases with increasing temperature, reaches a minimum value at 40°C, and generally shows a “V” -shaped distribution law. The coupling effect of temperature and crack aggravates the total damage of the backfill. (3) The strength criterion can reflect the relationship between the stress and strain of each limit state and the parameters of backfill with crack under different temperature conditions and can provide a certain reference for the evaluation of the stability of backfill with geological defects such as joints and crack in deep high temperature mines.  相似文献   
309.
Environmental Science and Pollution Research - The aim of this study was to investigate the effects of vermicomposting (VC) and thermophilic composting (TC) on the molecular transformation of...  相似文献   
310.
Environmental Science and Pollution Research - As the most sensitive and typical oasis city in the arid region of China, Jiayuguan, the role of land use change and urbanization in this region is...  相似文献   
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