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951.
零价铁还原降解活性染料   总被引:17,自引:0,他引:17  
曹加胜  王连生 《环境化学》1999,18(2):152-156
在分别通氮气,不通氮气和曝气的情况下,在水溶液中用零价铁还原降解活性染料。实验发现:在不同的氛围中,活性染料的降解程度不同,其降解程度为:暴气〉不通氮气〉通氮气。在不同通氮 和曝气的条件下,活性染料的降解过程中有黄色絮状沉淀生成,经红外光谱鉴定为三聚氯氰的取代产物。  相似文献   
952.
本文通过对江西省吉水县坡地资源现状、特点的分析,从未利用坡地、利用不充分坡地、利用不合理坡地3方面对吉水县坡地资源进行了潜力分析,并提出了开发利用坡地资源的途径  相似文献   
953.
ABSTRACT: One hundred and sixty-two rainfall-induced soil erosion tests were conducted to assist in predicting soil loss and subsequent increase in total suspended solids leaving a highway construction site during a rainfall event. A rainfall simulator and a water flume were constructed for the tests. Soil shear strength, compressive strength, rainfall intensity, and soil bed slope were treated as variables during the experiments. The soil with a higher shear strength resisted soil erosion better than lower strength soils. Soil loss was nearly independent of shear strength at low rainfall intensity but at high intensities, the shear strength was more important in resisting soil loss. Lower soil loss can be expected for cohesive soils if the compressive strength is high.  相似文献   
954.
Environmental Chemistry Letters -  相似文献   
955.
交联阳离子淀粉螯合剂对铬渣的处理研究   总被引:1,自引:0,他引:1  
合成了作为重金属螯合剂的交联阳离子淀粉 ,并将它用于铬渣的固化实验 ,对固化体的浸出毒性、表面浸出率、抗压强度等指标进行了测试。结果表明 ,添加高分子螯合剂后的固化体的浸出毒性降低 6 6 4 % ,远远小于国家标准的1 5mg/L ;2 8d后的表面浸出率仅为 1 0 -6数量级 ;抗压强度有所下降 ,但 2 8d养护后的抗压强度大于 30MPa ,符合填埋或建筑综合利用的强度要求  相似文献   
956.
ZH-02树脂对水中腐殖酸的吸附去除研究   总被引:1,自引:0,他引:1  
通过几种吸附树脂ZH 0 0、ZH 0 1、ZH 0 2、ZH 0 3、颗粒活性炭 (GAC)和AmberliteXAD 4对腐殖酸的静态吸附试验的筛选结果 ,发现大孔树脂ZH 0 2对腐殖酸具有较好的吸附效果。利用颗粒活性炭作为参照 ,探讨了ZH 0 2的动态吸附去除效果和脱附再生条件 ,发现常温下醇碱溶液效果较好。  相似文献   
957.
This article deals comprehensively with factors which influence attitudes to the placement of high-voltage overhead transmission lines (HVOTLs). It employs an analytical schema which links the initial stimulus of the power lines' proposal in an area to Background and Socio-economic independent variables and a set of mediating variables. From a survey of 600 residents in three different domiciliary settings in Queensland, Australia, results indicate an absence of positive attitudes and, at best, neutral ones to HVOTL placement. By multinomial logistic regression, the study probes the grounds behind negativity and extreme negativity, uncovering direct links between these attitudes and certain of the variables included in the analytical schema.  相似文献   
958.
The content of elements in fish tissues and organs from Swarz?dzkie Lake was investigated in order to evaluate the possible risk associated with their consumption by animals as well as humans. Samples of muscle, liver and fish bone of three fish species; roach (Rutilus rutilus), silver bream (Blicca bjoerkna) and crucian carp (Carassius carassius) were collected from seine catches undertaken as part of the biomanipulation of Swarz?dzkie Lake. Element concentration (Al, As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Zn) was determined by inductively coupled plasma mass spectrometry (ICP-MS), with the exception of Hg where the flow injection analysis system cold vapour atomic absorption spectrometry (FIAS-CVAAS) was applied. The study indicated a large variation in the occurrence of the investigated elements in different parts of the fish body. The highest content of Al and Zn was stated in all fish organs for each fish species. The majority of the applied statistical and chemometric methods (e.g., PCA, CA) refer to roach since we had a large number of data for this species. The obtained results were assessed in terms of their accuracy and precision using certified reference material of Fish Muscle ERM BB422.  相似文献   
959.
The negative effects of overexposure to ultraviolet (UV) radiation in humans, including sunburn and light-induced cellular injury, are of increasing public concern. 4-Methylbenzylidene camphor (4-MBC), an organic chemical UV filter, is an active ingredient in sunscreen products. To date, little information is available about its neurotoxicity during early vertebrate development. Zebrafish embryos were exposed to various concentrations of 4-MBC in embryo medium for 3 days. In this study, a high concentration of 4-MBC, which is not being expected at the current environmental concentrations in the environment, was used for the purpose of phenotypic screening. Embryos exposed to 15 μM of 4-MBC displayed abnormal axial curvature and exhibited impaired motility. Exposure effects were found to be greatest during the segmentation period, when somite formation and innervation occur. Immunostaining of the muscle and axon markers F59, znp1, and zn5 revealed that 4-MBC exposure leads to a disorganized pattern of slow muscle fibers and axon pathfinding errors during the innervation of both primary and secondary motor neurons. Our results also showed reduction in AChE activity upon 4-MBC exposure both in vivo in the embryos (15 μM) and in vitro in mammalian Neuro-2A cells (0.1 μM), providing a possible mechanism for 4-MBC-induced muscular and neuronal defects. Taken together, our results have shown that 4-MBC is a teratogen and influences muscular and neuronal development, which may result in developmental defects.  相似文献   
960.
In this paper, computational modeling is created for 3 MW wind turbine blade using the software Solidworks, and the computations are carried out using Workbench for the fluid–structure interaction of blades due to both the rated and the extreme wind load. The methods developed are applied to the simulation of the NREL Phase VI wind turbine blades, and validation against published data is presented. Moreover, the static structural analysis for wind turbine rotor is performed using Mechanical APDL. The results show that the maximum values of stress reach 458 MPa and 76.9 MPa due to the rated and extreme wind load, respectively, which are lower than 78.3 MPa, the flexural strength of Swancor 2511-A epoxy resin for blade material.  相似文献   
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