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1.
建立用流动注射--氢化物发生原子吸收法同时测定天然水中一丁基锡、二丁基锡、三丁基锡和四丁基锡化合物的方法.首先用NaBH4还原丁基锡化合物后冷凝富集、加热,氢化物根据沸点的不同依次解吸从而得到分离,由原子吸收法测定.本方法可测每升几十纳克(以锡计)的各种丁基锡化合物.  相似文献   

2.
1. 前言 由于以三苯基锡化合物(TBT)和三丁基锡化合物(TPT)为代表的有机锡化合物(OTC)对微生物等有很强的毒性,因而生产量大并被用作船底涂料的防污染剂,防霉菌剂,杀虫剂及农药等等。根据环境厅最近进行的调查结果,TBT已在环境试样(底质试样)和鱼介类之类的生物试样中有检出,尤其是对海域鱼介类的污染波及范围甚广。但是,对于与TBT有同样作用,并被大量用于防污染剂和农药的TPT,其在环境中的污染形态目前还没怎  相似文献   

3.
业已建立了一种基于采用可放大信号的介质的石墨炉原子分光光度法的分析方法,来测定海水中的无机锡和两种三取代有机衍生物.采用捕集于石墨化碳黑上的富集法(富集因子高达8×10~4)和在小硅胶交换柱上的分离法,可分别测定2×10~(-12)和2.8×10~(-12)mol/L的三苯基锡和三丁基锡化合物.未吸附在石墨化碳黑上的无机锡,利用其吡咯烷二硫代氨基甲酸盐络合物的液一液萃取法,使其进入二氯甲烷,而从基体液中分离出来.本法测定ng/L级含量时的回收率高(≥95%),精密度好(≤5%).  相似文献   

4.
锡斯基威特湖(Siskiwit)是个遥远的小湖,位于美国和加拿大之间的苏必利尔湖罗耶尔岛,此岛1940年被定为美国国家公园,很少有人类活动.从锡斯基威特湖捕捞的湖鳟和白鲑测定出许多种有机氯化合物,证明一些有机氯农药和多氯联苯(PCBs)能远距离输送.另外,工业生产的氯丹、八氯苯  相似文献   

5.
对汽油添加剂甲基叔丁醚(MTBE)的吸收、体内分布、生物半减期、排泄等生物代谢和毒性及对人群肿瘤发病等健康影响的研究进展做一综述.  相似文献   

6.
应用线性溶剂能参数建立了准确预测硝基芳烃对隆线蚤的急性生物毒性EC50模型,对有基芳烃其模型为lgEC50-1.504-6.893Vi/100-0.298π0.151βm-0.427αm,该模型具有计算简单,预测准确性大、精密度高的特点。应用该模型可以预测大范围内单硝基芳烃的毒性EC50值。  相似文献   

7.
3种大环内酯类抗生素对海洋发光菌的毒性作用   总被引:1,自引:0,他引:1  
以海洋发光菌为受试生物,研究了红霉素、罗红霉素、乙酰螺旋霉素3种抗生素的单一和联合毒性作用。基于常见的3种联合作用评价方法,对混合体系的联合毒性作用进行了评价研究。结果表明,3种抗生素对发光菌单独作用的半最大效应浓度(EC50)分别为:0.725 9×10-3,1.207 8×10-3和0.633×10-3mol/L;二元联合体系对发光菌的毒性强弱为:红霉素+乙酰螺旋霉素>罗红霉素+红霉素>罗红霉素+乙酰螺旋霉素。3种抗生素联合体系作用类型的不同与每种抗生素不同取代基对微生物生理生化过程的影响有关。在选择的联合研究体系中,以毒性单位法获得参数的数值较大,灵敏度较高。研究大环内酯类抗生素对发光菌的毒性作用可为环境风险评价提供基础数据。  相似文献   

8.
简述了饮用水消毒副产物(DBPs)的基因毒性与致癌性的研究进展。从Ames试验、SOS/umu试验、彗星试验、微核试验及一些新颖的致突变试验结果对DBPs基因的毒性,以及从毒理学实验、流行病学研究和致癌风险评估3个方面对DBPs的致癌性进行了分析和总结,以期为今后饮用水DBPs毒性效应及其致毒机理研究提供参考,进而促进饮用水质量管理与立法的发展。  相似文献   

9.
一、锌对哺乳动物的毒性 锌是一种生命必需的基本生物元素;然而,生物体接触过量的锌也会引起个别器官和系统的基本功能状态紊乱。 60只大鼠每天以50毫克/公斤(三个月)及7毫克/公斤和3.5毫克/公斤(五个月)的剂量口服氧化锌,都引起肝毒性效应。试验结束时,50毫克/公斤剂量组大鼠的四溴酚酞磺酸钠保留系数上升到46.3(试验前为17.1),7毫克/公斤剂量组上升到 27.5(试验前为11.0),肝脏精  相似文献   

10.
水质生物毒性在线监测技术研究进展   总被引:4,自引:1,他引:3       下载免费PDF全文
从生物分子、细胞、个体、种群和群落水平,系统介绍了国内外研发的水质毒性在线监测技术,归纳分析了各种技术的特点及应用,并提出了其发展前景与趋势。  相似文献   

11.
An important research area in life sciences is devoted to modeling, prediction, and dynamics of gene-expression patterns. As clearly understood in these days, this enterprise cannot become satisfactory without acknowledging the role of the environment. To a representation of past, present, and most likely future states, we also encounter measurement errors and uncertainties. This paper surveys and improves recent advances in understanding the foundations and interdisciplinary implications of the newly introduced gene–environment networks, and it integrates the important theme of carbon dioxide emission reduction into the networks and dynamics. We also introduce some operational and managerial issues of practical working and decision making, expressed in terms of sliding windows, quadrants (modules) of parametric effects, and navigating (controlling) between such effects and directing them. Given data from DNA microarray experiments and environmental records, we extract nonlinear ordinary differential equations that contain parameters that have to be determined. For this, we employ modern (Chebychevian) approximation and (generalized semi-infinite) optimization. After this is provided, time- discretized dynamical systems are studied. A combinatorial algorithm with polyhedra sequences allows to detect the region of parametric stability. Finally, we analyze the topological landscape of gene–environment networks with its structural (in)stability. By embedding as a module and investigating CO2 emission control and figuring out game theoretical aspects, we conclude. This pioneering work is theoretically elaborated, practically devoted to health care, medicine, education, living conditions, and environmental protection, and it invites the readers to future research.   相似文献   

12.
Increasingly public and governmental agencies are concerned aboutrevitalizing coastal environments. Understanding how the publicuses these areas, and what they see as the most important improvements to these regions is critical to their assessment andmanagement. Uses of three estuaries, and perceptions of possiblemanagement and restoration options, were examined for people whowere interviewed in the New York/New Jersey Harbor, Manasquan Inlet, and Barnegat Bay, New Jersey. Nearly 90% of the people interviewed listed pollution as New Jersey's most important environmental problem. Most people (68%) used the habitat for outdoor sports, but rated communing with nature, walking, and the provision of open `green' space as the most valued uses. Pollution prevention was the most often mentioned habitat improvement desired, and people rated removing pollution, cleaning up garbage, and creating more fish breeding habitat the highest. There were significant locational differences inhow people used the estuaries, and in how they thought they should be improved. People from Barnegat Bay ranked most uses higher than did people from elsewhere, while the people from Manasquan Inlet rated the importance of most remediation and restoration actions higher. Many of the improvements fall withinenvironmental management, including (rank order from high to low)creating more fish breeding habitat, improving native vegetation,improving habitat for birds, increasing plant diversity,improving habitat for butterflies, and enlarging adjacentmarshes. The data provide clear support for the importance ofthese coastal habitats for communing with nature and having open`green space' spaces, and for providing recreationalopportunities. To enhance their value, people want to removepollution and improve both the habitat quality and the educational and recreational facilities.  相似文献   

13.
Fate Modelling of DEHP in Roskilde Fjord, Denmark   总被引:1,自引:0,他引:1  
The fate of di(2-ethylhexyl)phthalate (DEHP) is modeled in Roskilde fjord, Denmark. The fjord is situated near Roskilde, which comprises 80,000 PE, various industries, a central wastewater treatment plant, and adjacent agricultural fields. Roskilde fjord is thus a suitable recipient for studying the transport and fate of DEHP, which is used in a variety of different industries and consumer products. Wastewater from households and industries is led to the local wastewater treatment plant, which leads the effluent to the fjord. The sludge is partly stored and partly amended on an adjacent field. The model applied in the present study is a simple box model coupling water and sediment compartments of the fjord with wastewater treatment plant effluent, streams leading to the fjord, and atmospheric deposition. The fjord model comprises first-order degradation, adsorption, sedimentation, vertical diffusion in the sediment, dispersive mixing in the water, and water exchange with the surrounding sea. Experimental measurements of DEHP were made in the fjord water and sediment, in the wastewater treatment plant inlet and effluent, and in streams and atmospheric deposition. The experimental data are used to calibrate the model. The model results show that freshwater from streams is the predominant DEHP source to the fjord, followed by atmospheric deposition and effluents from wastewater treatment plants. Sedimentation is the predominant removal mechanism followed by water exchange with the sea and degradation.  相似文献   

14.
Metal concentrations in deciduous tree leaves from urban areas in Poland   总被引:1,自引:0,他引:1  
Accumulation of metals in deciduous tree foliage fromurban areas in western-south Poland was monitored duringthe vegetation season of 2000 year. Concentrations of Al,Ba, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sr, Ti and Znwere measured in birch, willow, linden and maple leavesusing the ICP-AES method. Seasonal variations of metalconcentrations and their relations with sampling sitewere investigated. The most dynamic accumulation of Al,Cd, Cr, Ni and Pb was observed for examined species. Thehighest differences in element concentrations forinvestigated sites were found for Ba, Cd, Mn and Ni.Interelement correlations were investigated. In allfoliar samples synergistic relationships between Al–Crand Ca-Sr were found. Statistically significant negativecorrelations were observed only for Cd and Ti in birch leaves.  相似文献   

15.
污水处理厂出水中主要离子和重点元素的浓度特征及去除效果会影响受纳水体的盐度、碱度等指标,从而影响河湖的生态服务功能,但是这方面的研究长期以来未得到充分关注。在陕西省全境选择51家城镇污水处理厂,测定进水和出水中的钾、钙、钠、镁、氟、氯和硫酸根离子,以及铁、锰、硼、钼、锶等重点元素的浓度。测定结果显示:陕西省城镇污水处理厂进水和出水中的阳离子以钠离子为主,其次是钙、镁离子,钾离子浓度最低;阴离子中,氯离子浓度最大,其次为硫酸根离子。就总离子浓度而言,陕北和关中地区污水处理厂进水的离子浓度普遍高于陕南地区。相关性分析结果显示:在污水处理厂进水中,钠、氟、氯、镁及硫酸根离子相互之间均呈现显著正相关关系;铁、锰在进水中没有表现出明显的相关关系,而在出水中呈现显著的正相关关系。污水处理厂仅能够处理污水中少量的氟、钾和镁离子。铁元素和锰元素在经过污水处理厂的处理后,浓度有所升高。此研究的研究结果可为河湖水化学组成管理决策提供参考。  相似文献   

16.
Criteria and Indicators of Sustainable Forest Management   总被引:2,自引:0,他引:2  
  相似文献   

17.
Understanding the ecology, condition, and changes of coastal areas requires data from many sources. Broad-scale and long-term ecological questions, such as global climate change, biodiversity, and cumulative impacts of human activities, must be addressed with databases that integrate data from several different research and monitoring programs. Various barriers, including widely differing data formats, codes, directories, systems, and metadata used by individual programs, make such integration troublesome. Coastal data partnerships, by helping overcome technical, social, and organizational barriers, can lead to a better understanding of environmental issues, and may enable better management decisions. Characteristics of successful data partnerships include a common need for shared data, strong collaborative leadership, committed partners willing to invest in the partnership, and clear agreements on data standards and data policy. Emerging data and metadata standards that become widely accepted are crucial. New information technology is making it easier to exchange and integrate data. Data partnerships allow us to create broader databases than would be possible for any one organization to create by itself.  相似文献   

18.
山西省大气降水水质评价   总被引:1,自引:0,他引:1       下载免费PDF全文
为了解山西省大气降水水质状况、主要污染物及区域分布规律,山西省水文部门于1984年开始对大气降水进行监测。在全省9个地市布设测点,分别为:太原市、大同市、长治市、榆次市、临汾市以及吕梁、忻州、阳泉、运城地区。监测项目为H^2 、电导率、Ca^2 、Mg^2 、K^2 、Na^2 、NH4^2 、SO4^2-、NO3^-、Cl^-、CO3^-、HCO3^-、F^-。结果表明,除吕梁、忻州地区外。山西省各地市均有酸雨发生,但酸雨发生的频率不高,全省年平均为3.3%;酸雨的酸性程度也不高,对生态可造成明显影响的降水次数不多;山西省酸雨为典型的硫酸型,酸雨中硫酸与硝酸的质量浓度比值远高于全国平均值。  相似文献   

19.
We examined the response of demographic, morphological, and chemical parameters of turtle grass (Thalassia testudinum), to much-higher-than-normal rainfall associated with an El Niño event in the winter of 1997–1998. Up to 20 inches of added rain fell between December 1997 and March 1998, triggering widespread and persistent phytoplankton blooms along the west coast of Florida. Water-column chlorophyll concentrations estimated from serial SeaWiFS imagery were much higher during the El Niño event than in the previous or following years, although the timing and magnitude of phytoplankton blooms varied among sites. Seagrass samples collected in 1997, 1998, and 1999 provided an excellent opportunity to test the responsiveness of Thalassia to decline and subsequent improvement of water quality and clarity in four estuaries. Using a scoring technique based on temporal responsiveness, spatial consistency, and statistical strength of indicators, we found that several morphological parameters (Thalassia shoot density, blade width, blade number, and shoot-specific leaf area) were responsive and consistent measures of light stress. Some morphological parameters, such as rhizome apex density, responded to declines and subsequent improvement in water clarity, but lacked the statistical discriminating power necessary to be useful indicators. However, rhizome sugar, starch, and the total carbohydrate concentrations also exhibited spatially and temporally consistent variation as well as statistical strength. Because changes in shoot density, as well as water clarity, affect rhizome carbohydrate levels, a composite metric based on Thalassia shoot density and rhizome carbohydrate levels together is probably more useful than either parameter alone as an indicator of seagrass health.  相似文献   

20.
用AQUA800辨别分析仪同时测定地面水中的氨、硝酸盐、亚硝酸盐、氯化物、正磷酸盐、总硬度和硅酸盐,是一种简便、迅速、准确、可靠的测定方法,样品无需预处理,精密度试验其变异系数分别为1.24%、2.18%、2.02%、2.67%、2.35%、3.57%、4.78%,加标回收率分别为103.5%、101.0%、95.0%、99.2%、97.6%、101.5%、98.0%,方法检测限分别为氨0.022mg/L,硝酸盐0.015mp/L,亚硝酸盐0.002tug/L,氯化物0.47mg/L,正磷酸盐0.015mg/L,总硬度17.6mg/L,硅酸盐0.55mg/L,能满足地面水中辨别分析仪同时测定氨、硝酸盐、亚硝酸盐点化物、正磷酸盐、总硬度和硅酸盐分析测定的要求。  相似文献   

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