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1.
本文以SO4^2-与过量Ba^2+形成BaSO4沉淀反应为基础,较详细地讨论了反应条件,从而拟定了用AAS和ICP-AES间接测定天然水中SO4^2-的方法、确定了方法的精密度,AAS法的RSD%为1.5,ICP-AES法为3.2, 两种方法对比分析的结果接近,误差为1.0%(相对)。用于天然水中SO4^2-的测定,获得满意的结果。  相似文献   

2.
AAS法测定中药川附子微量重金属元素   总被引:6,自引:3,他引:3  
本工作采用AAS法分析中药川附子微量重金属元素。通过对连翘标准样品的分析并与ICP-AES法的结果比较,确定了分析方法的准确度。应用该法弄清了川附子炮制前后微量重金属的含量及其浓度变化情况,从而为中药的开发与国际化提供了科学依据  相似文献   

3.
ICP-AES法测定中药川附子微量重金属元素   总被引:12,自引:6,他引:6  
本工作采用ICP-AES法分析中药川附子中微量重金属元素。通过对潞党参标准样品的分析与AAS法的结果比较,确定了方法的准确度。应用该法弄清了川附子炮制前后微量重金属的含量及其浓度变化情况,从而为川附子的开发与国际化提供了科学依据。  相似文献   

4.
间接原子吸收法测定水中氯化物研究   总被引:6,自引:2,他引:6  
本工作以Cl^-与过量Ag^+生成AgCl沉淀反应为基础,较详细地探讨了各种强电解质作为絮凝剂对AgCl沉淀的影响,确定了反应的条件,从而提出了一个测定水中Cl^-的是接原子吸收法,Cl^-浓度在0-50μg/10ml范围呈线性,用建立的方法测定自来水中Cl^-,再现性与准确度俱佳,用本法测定废水中Cl^-的结果与经典的比浊法,和离子色谱法的结果相符。  相似文献   

5.
序批式活性污泥法(SBR)技术及关键设备研究与探讨   总被引:9,自引:0,他引:9  
本文对序批式活性污泥法(简称SBR)在污水处理技术中的发展状况、运行原理及工艺特点进行了分析与论述。与较传统的活性污泥法相比,SBR法具有处理构物少、处理过程简化的特点,整个操作由进水、反应、沉淀、排水和闲置五个基本过程所组成。上述过程都在一个反应池内依次进行,省去了初沉池、二沉池和回流污泥泵房。因SBR为延时曝气工艺,故污泥已好氧稳定,不需消化处理,工程造价亦可降低。随着SBR法近十多年来在国内外迅速的发展和不断改进的情况,本文对由此派生出的ICEAS法、CASS法、IDEA法及DAT-LAT法进行了说明。另外,对SBB法中关键设备尾水机械的结构及特点进行了对比与分析,论述了其负荷、滗水范围、保护高等多项参数的确定结果。  相似文献   

6.
何林  奚治文 《四川环境》1993,12(1):28-30
本文拟定了一种测定马拉硫磷残留量的极谱法,在0.1mol/LNaOH基底溶液中,用单扫描示波极谱仪制作其阴极化一阶导数极谱曲线,峰电位Ep为-0.42V(vs.SCE),在0.08-0.5μg/ml范围内i'p与浓度间呈线性关系。讨论了一些常见农药及离子的干扰情况,以及影响溶出峰电流的因素。方法应用于环境水样中马拉硫磷残留量的测定。变异系数在10%以内。  相似文献   

7.
简易流动注射仪化学发光法测定水环境中的铵态氮   总被引:3,自引:0,他引:3  
杨季冬 《四川环境》2002,21(1):41-42,48
在0.1M的碱性条件下,NBS(N—溴代丁二酰亚 胺)在荧光素的增敏作用下氧化氯化铵,产生强的化学发光。基于此本文详细研究了其反应 的特性和影响因素,在优化的实验条件下体系对氯化铵的测定范围为1.0×10-7~1 .5×10-5g/mL,检出限为3.6×10-8g/mL,对5.0×10-6g/mL氯化铵 进行11次平行测定,其RSD为2.8%。将本法用于环境水样中NH+4的分析,并与常规的 方法进行对照,获得了满意的结果。  相似文献   

8.
Super-CM利水净是利用MAB技术研究成功的一种用于治理水污染的新产品。本文介绍了Super-CM利水净结合活性污泥法处理生活污水的一则现场试验案例。试验结果表明,在活性污泥法中加入Super-CM利水净能够有效的提高污水处理能力,在试验后期进水增加30%的情况下,COD、SS的平均去除率仍然分别提高了8.7%、4.1%。  相似文献   

9.
德国PASSAVANT公司完善生物法去除水中的氮和磷EliminatingtheNitrogenandPhosphorusinWaterwithImprovedMicrobeMethodinGermanPASSAVANTCompany为了去除水体中高...  相似文献   

10.
用气相色谱/质谱(GC/MS)研究分析了环境中的半挥发性有机标准物。以十氟三苯基磷作调机物,对GC/MS仪器系统进行了调整,离子丰度值符合美国环保局(U.S.EPA)1986年推荐的离子丰度标准。测定了32种目标化合物的保留时间及相对保留因子RF值,结果表明除五氯苯酚不达标外,其余化合物的RF值均符合要求,31种目标化合物的加标回收率为21%~97%,相对标准偏差为3.1%~24.1%,符合美国环保局8270方法质量控制检验标准。最后对建立定量校正库与GC/MS分析进行了讨论  相似文献   

11.
Urban and industrial areas continue to expand and consequently, to create serious water pollution problems to natural streams. The need for the development of accurate, reliable, and sensitive water quality prediction models is most desirable. The first objective of this research is to set guidelines for dividing a natural stream into more or less independent reaches based on some criteria. The second objective is to obtain the predicting equations of the water pollutants in a selected stream. The preliminary phase of this research evaluated water quality data sampled from the Pearl River which flows southwest and then turns south through the states of Mississippi and Louisiana. This evaluation served as guidelines to divide the total river basin into reaches (subsystems) appropriate to the objective of this research. Subsequent to this subsystem assignment, a stepwise multiple regression FORTRAN program was used to regress the pollutants (dependent variables) for both time and space on their water characteristics (independent variables). Based on the results obtained, the proposed statistical approach provides a practical tool for developing regression equations for the purpose of water pollutants' prediction.  相似文献   

12.
文章综合分析了影响泸定县农业生态系统因素间的关系,建立了评价与决策分析层次模型。通过层次模型判断矩阵的运算,求出各层次因素相对目标层重要性的合成权值,并在此基础上评价泸定县农业资源生态系统的效益水平和优选该系统建设决策措施实施的最佳顺次结构。  相似文献   

13.
14.
ABSTRACT: This paper presents a quantitative assessment framework for determining the instream flow under multiobjective water allocation criteria. The Range of Variability Approach (RVA) is employed to evaluate the hydrologic alterations caused by flow diversions, and the resulting degrees of alteration for the 32 Indicators of Hydrologic Alteration (IHAs) are integrated as an overall degree of hydrologic alteration. By including this index in the objective function, it is possible to optimize the water allocation scheme using compromise programming to minimize the hydrologic alteration and water supply shortages. The proposed methodology is applied to a case study of the Kaoping diversion weir in Taiwan. The results indicate that the current release of 9.5 m3/s as a minimum instream flow does not effectively mitigate the highly altered hydrologic regime. Increasing the instream flow would reduce the overall degree of hydrologic alteration; however, this is achieved at the cost of increasing the water supply shortages. The effects on the optimal instream flow of the weighting factors assigned to water supplies and natural flow variations are also investigated. With equal weighting assigned to the multiple objectives, the optimal instream flow of 26 m3/s leads to a less severely altered hydrologic regime, especially for those low‐flow characteristics, thereby providing a better protection of the riverine environment.  相似文献   

15.
Agri-environmental schemes (AES) are the main policy instrument currently available in the EU to promote environmentally-friendly farming practices. However, the rate of adoption of these measures is still relatively low in southern Europe, and understanding how these rates can be increased is still an open issue. The goal of this paper is to increase that understanding by testing whether the factors which determine AES sign-up decisions are influenced by the intensity of change in farming practices that are brought about by adopting the scheme. A micro-economic model reflecting farmer AES sign-up decisions is proposed and applied to two schemes in Spain respectively requiring major or minor intensity of change in practices by surveying farmers eligible for both schemes. The results show that farm structural factors play a role when major practice change is required by the scheme, yet when dealing with minor change, individual farmer characteristics play a more determining role. Social capital and farmer attitude are important factors in both the AES surveyed. Therefore, it may be concluded that improving agronomic design would be an important tool to improve farmer participation in AES where major change is involved, whereas improved targeting and extension would help uptake for AES involving a lesser degree of change.  相似文献   

16.
The Washington State Environmental Policy Act (SEPA) promotes the conservation of natural resources through procedural review of proposed actions which may impact natural systems. There are, however, many actions specifically exempt from the SEPA review process. Since many exempt actions could have significant adverse effects on natural resources at one location and not another, the SEPA statute contains a provision that enables local governments to designate Environmentally Sensitive Areas (ESAs). Within the ESAs, these potentially adverse activities are subject to SEPA review. Local governments have complete control over the exact definition of the ESA criteria and the types of local projects exempt from SEPA. Whitman County, the most productive wheat-producing county in Washington, has recognized the need for conservation of its natural resources in its comprehensive plan but has not implemented the ESA provision. A representative watershed within Whitman County was used as a case study to identify areas which would qualify for ESA status. In these areas, specific soil, water, and biological characteristics or resources were identified as sensitive to certain common land uses. Significant differences were found between state and county policies regarding ESAs and actual conditions within the watershed. It may be more effective for the state to manage ESAs on a consistent and regional basis.  相似文献   

17.
ABSTRACT: Dissolved gas analysis permits direct detection of ground water denitrification, a technique we used in this study to assess the fate of nitrate in a riparian wetland. Dissolved argon (Ar) and dinitrogen (N2) were measured in transects of nested piezometers installed at different depths within upwelling regions of a riparian wetland. The method uses the Ar content in the water as a natural inert tracer for assessing background content of N2 from the previous air/water equilibrium. Within the wetland under study, anoxic to suboxic ground water became more oxic in piezometers close to the aquifer layer, indicating upwelling of oxic ground water. Assessment of loss of nitrate and Ar in ground water within an upwelling zone indicated that shallow piezometers had significant N2 loss through degassing. Most of the measured nitrate‐nitrogen (NO3?‐N) loss of 205 μM in a piezometer nest could be accounted for by total N2‐N produced (169 μM N), calculated from changes in dissolved N2 and estimated N2 degassed. Degassing due to methane (CH4) production was also detected in some shallow piezometers within nests. This technique for analysis of dissolved gases in ground water can be applied to detect small changes in N gas concentration and aids in assessing the fate of nitrate along a ground water flow path.  相似文献   

18.
This study proposes an improved integrated water resource management (IWRM), in which water conservation was analyzed for the entire water use process. A multi-objective optimization method was applied to optimize the IWRM, which investigated the reduction of freshwater consumption and the total water supply cost. Customer's preference for saving water and an end use analysis (EUA) was applied in the water conservation analysis. Taking Tianjin as the study area, a reduction in customer's economic pressure (EP) was utilized to evaluate the degree of the customer's preference for saving water. The results revealed that agriculture had a greater preference for saving water than other sectors, where as the public had the weakest motivation for saving water. Improving the transportation method could contribute 62.1% of the total water savings in the agriculture sector. The optimization of the IWRM demonstrated that the local freshwater savings would be 21.5%, and the total cost for water supplies would decrease by 13%. However, a government subsidy of 87.5 million Yuan would be needed. Additionally, by analyzing the change in the amount of water savings affected by water price, the appropriate water price increase range was suggested to be 1.5–1.7 times the original price.  相似文献   

19.
ABSTRACT: South Florida and the Everglades have been under intensive development since 1850 by Federal and State governments who encouraged and financed extensive drainage and hydraulic changes, primarily for agricultural settlement. Agricultural development of the sugar industry in the northern Everglades adjacent to Lake Okeechobee rapidly progressed only after the 1900s. Political and resource management conflicts have arisen because policies which once favored development are now being reversed by policies and regulation efforts to restore and conserve natural ecosystems. Currently, the environmental and ecological impacts of agricultural land use adjacent to natural wtlands of the Everglades are being assessed. The objectives of this paper are: (1) to outline the historical development of south Florida and the sugar industry, (2) to relate this history to political and management policy changes occurring as it pertains to ecosystem restoration and the multiuser competition for water/land resources, and (3) to propose how integrated resource management might be utilized for a sustainable Everglades and south Florida. This paper outlines the historical paradox of urban settlement, land development, and agricultural production, with efforts in the recent decade to acquire, manage, and preserve land and water resources for natural areas conservation. Only though the use of integrated resource management will the defined resource conflicts be mediated.  相似文献   

20.
超临界水氧化中设备腐蚀的研究现状   总被引:2,自引:0,他引:2  
陈娟娟  杨海真 《四川环境》2007,26(2):101-104,112
超临界水氧化(SCWO)技术是近年发展起来的处理有机难溶废物的安全高效的新技术。在阐述超临界水的物理、化学性质的基础上,介绍了SCWO反应的工作原理和流程,分析总结了世界范围内开展的SCWO环境中设备腐蚀及监测技术等方面的研究动态,提出了我国SCWO技术研究的未来发展方向。  相似文献   

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