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1.
多道石墨炉原子光谱法同时测定水中的Cu,Pb,Zn,Cd   总被引:2,自引:2,他引:0  
使用多道石墨炉原子吸仪,采用石墨管涂层处理技术,在对几种基体改进剂的改进作用进行实验比较的基础上,选择1%ZrOCl2为基体改进剂,对水中的Cu,Pb、Zn、Cd4种元素进行了同时测定,并应用此方法对北京化工二厂和京密引水渠的水样进行了加标回收试验,取得了较为满意的结果。  相似文献   

2.
水中二氧化氯,氯,亚氯酸根和氯酸根区分测定法   总被引:7,自引:1,他引:6  
为了保护人类健康制定卫生规范,同时为ClO2的研究和应用提供基础手段,必须要建立一种能准确区分测定水中ClO2,Cl2,ClO^-12,ClO^-3浓度的方法。回顾了现有水中ClO2,Cl2,ClO^-2和ClO^-3的区分测定方法,评述了各种测定方法的优缺点和适用性,指出了目前在区分测定这恨氧化物的方法中存在的问题,提出了解决问题的途径。  相似文献   

3.
通过对地面水中CODcr多年的监测,取得了地面水中CODcr的浓度波动范围,为提高工作效率,将文献「1」中加热回流2h改为1h,并做了某些条件试验及对比试验,结果令人满意。  相似文献   

4.
二氧化氟是一种具有广阔应用前景的饮用水消毒剂,制备和使用时可能产生一系列氯的不同氧化态物质,其中最主要的是ClO2、ClO2和ClO3,本研究用紫外分光光度法分别测定了ClO2和ClO2的含量,同时用改进的碘量法分别测定溶液中同时存在的ClO2、ClO2和ClO3,并讨论了有关的反应机理,测定的精密度和准确度均满足一般饮用水质分析的需要。  相似文献   

5.
油轮压舱废水的特性分析   总被引:1,自引:0,他引:1  
对油轮压舱废水的可生化性进行了分析研究,既讨论了压舱废水的BOD5与COD的相关关系,又分析了COD与TOC比值,同时还用色谱-质谱作了压舱废水中有机组分的分析。三方面的结果均表明油轮压舱废水的可生化性较差,压舱废水中有机组分以高分子量的直链烷烃为主。在此基础上,提出了对油轮压舱废水的处理建议。  相似文献   

6.
高氯离子废水中低浓度化学需氧量分析技术   总被引:11,自引:0,他引:11  
用回流法和烘箱法测定高氯离子废水中低含量COD。着重试验了氧化剂浓度对氯离子的影响,并是出COD校正式,给出了标准样品和废水样的测定结果。  相似文献   

7.
用自制消解液替代进口试剂测定化学需氧量   总被引:1,自引:0,他引:1  
用美国进口试剂在HACH仪器上测试CODcr,具有准确度高、方法简便、安全、快速、节省试剂、防止有机物挥发等优点,但存在的问题是试剂价格昂贵、样品测试成本很高。为解决这一问题,经过多次试验,自行研制出了消解液试剂、经与进口试剂对比试验,结果令人满意,大大降低了样品测试成本。  相似文献   

8.
在线富集进样—火焰原子吸收法测定水中低含量Cu,Pb,Cd   总被引:3,自引:0,他引:3  
用在线富集进样火焰原子吸收法测定水中低含量Cu,Pb,Cd,富集倍数分别烟122、136和94倍,相对标准为16%、15%和4.6%,检测限为1.6μg/L和0.18μg/L。探讨了分析精密度差的原因;改进了富集进样方法。  相似文献   

9.
南四湖港口污染物扩散区COD降解系数的研究   总被引:1,自引:0,他引:1  
本文对南四湖港口污染物扩散区内的COD降解规律进行了室内模拟试验研究,采用最小二乘法估计出了COD可降解部分的降解系数和不可降解部分的百分比,并通过方差分析验证了模型的可靠性。COD降解系数和不可降解百分比的获取,可以为预测各港口对南四湖水质变化趋势的影响,为制定相应的水污染防治规划和措施,提供了重要的基础数据。  相似文献   

10.
重铬酸钾法测定COD回流时间的探讨刘艳(石河子市环境监测站832000)重铬酸钾法测定COD,测定结果准确、重现性好,是目前通用的一种标准分析方法。但是此标准方法存在加热回流时间过长(2h)的问题,为了缩短加热回流时间,提高工作效率,对重铅酸钾法测定...  相似文献   

11.
阐述了离子色谱法测定酸雨中的钠、铵、钾、镁、钙含量的方法和步骤。结果表明,各元素的检出限均低于0.02 mg/L,加标回收率为90%~110%,相对标准偏差均低于1%,结果令人满意。该方法可同时测定酸雨中的5种阳离子,并且操作便捷,值得推广与应用。  相似文献   

12.
研究了大气降尘中铅、锌、铜、铁等金属元素的原子吸收光谱测定方法,用氢氟酸消解法对降尘进行预处理,并对方法的精密度、准确度进行了检验,结果较为满意.该法简便、快速、灵敏.  相似文献   

13.
A study of heavy metal contents in freshwater snails from rice fields have been made. The results indicate that the levels of heavy metals, Pb, Cu, Zn and Cd, are low and within the permissible limit of Malaysian Food Regulations. The results can serve as background data for further reference.  相似文献   

14.
Compost and digestate are important recycling fertilizers and have beneficial effects on soil parameters. However, they can contain significant amounts of organic pollutants. Here, the first comprehensive data set on dibenzo-p-dioxins and -furans (PCDD/F), dioxin-like polychlorinated biphenyls (DL-PCB), brominated flame retardants, perfluorinated alkyl substances (PFAS), pesticides, phthalates, nonylphenol and chlorinated paraffins (CP) in source-separated compost and digestate from Switzerland is presented (n = 3-18). The median summation 17PCDD/F and summation 12DL-PCB concentrations were at 3.2 ng I-TEQ kg(-1)dry weight (dw) and 3.0 ng WHO-TEQ kg(-1)dw, respectively. Brominated diphenyl ether 209 (BDE 209) accounted for 72% of the total polyBDE content (10 microg kg(-1)dw). Hexabromocyclododecane (HBCD) and tetrabromobisphenol A (TBBPA) levels were at 100 and 0.51 microg kg(-1)dw, respectively. PFAS were identified for the first time in compost and digestate (median concentration 6.3 microg kg(-1)dw, summation 21compounds). Out of 269 pesticides analysed, 30 fungicides, 14 herbicides, eight insecticides and one acaricide were detected. Di-(2-ethylhexyl)phthalate (DEHP) median concentration accounted for 280 microg kg(-1)dw and nonylphenol was below the detection limit of 1 mg kg(-1)dw. The sum of short and medium chain CP was between 90 and 390 microg kg(-1)dw. The concentrations observed were at or above the levels found in background soils, which are the main recipient of compost and digestate. Where actually applied, compost can contribute considerably to the total input of organic pollutants to the soil. However, on a total Swiss agricultural area base, inputs seem to be limited.  相似文献   

15.
The integration of ecosystem services and accounting systems can help different stakeholders understand the economic implications of environmental impacts. Any such integration requires clear understanding of how ecosystem services may match and integrate with traditional accounts. The Experimental Ecosystem Accounts (EEA) of the System of Integrated Environmental and Economic Accounts (SEEA) is developing quickly with applications at different administrative levels. One emerging feature is lack of agreement on conceptual notions and definitions that could reconcile different approaches. Some basic issues can be developed and solved only once a theoretical basis has been established. Since the first step of any application is to identify which ecosystem services to account for, this paper explores whether and to what extent the theoretical frameworks behind ecosystem services classification systems match the theoretical framework behind the SEEA EEA. This attempt first tackles the conceptual framework on the accounting side, then the conceptual framework on the ecosystem services classification side. Combining the two sides, it is possible to visualize matches or mismatches and to infer a few consequences and implications. Ecosystem services classification systems can guide separation of intra-ecosystem processes from final ecosystem services, and help disentangle ecosystem services from benefits, key requirements for integrating accounts.  相似文献   

16.
Resilience is a rehashed concept in natural hazard management—resilience of cities to earthquakes, to floods, to fire, etc. In a word, a system is said to be resilient if there exists a strategy that can drive the system state back to “normal” after any perturbation. What formal flesh can we put on such a malleable notion? We propose to frame the concept of resilience in the mathematical garbs of control theory under uncertainty. Our setting covers dynamical systems both in discrete or continuous time, deterministic or subject to uncertainties. We will say that a system state is resilient if there exists an adaptive strategy such that the generated state and control paths, contingent on uncertainties, lay within an acceptable domain of random processes, called recovery regimes. We point out how such recovery regimes can be delineated thanks to so-called risk measures, making the connection with resilience indicators. Our definition of resilience extends others, be they “à la Holling” or rooted in viability theory. Indeed, our definition of resilience is a form of controllability for whole random processes (regimes), whereas others require that the state values must belong to an acceptable subset of the state set.  相似文献   

17.
Combining genotoxicity/mutagenicity tests and physico-chemical methodologies can be useful for determining the potential genotoxic contaminants in soil samples. The aim of our study was to evaluate the genotoxicity of soil by applying an integrated physico-chemical-biological approach. Soil samples were collected at six sampling points in a Slovenian industrial and agricultural region where contamination by heavy metals and sulphur dioxide (SO2) are primarily caused by a nearby power plant. The in vitro alkaline version of the comet assay on water soil leachates was performed with Caco-2 and HepG2 cells. A parallel genotoxicity evaluation of the samples was performed by Ames test using Salmonella typhimurium and the Tradescantia micronucleus test. Pedological analyses, heavy metal content determination, and different physico-chemical analyses, were also performed utilizing standard methodology. Water leachates of soil samples were prepared according to standard methods. Since only a battery of biotests with prokaryotic and eukaryotic organisms or cells can accurately estimate the effects of (geno)toxicants in soil samples and water soil leachates, a combination of three bioassays, with cells or organisms belonging to different trophic levels, was used. Genotoxicity of all six water soil leachates was proven by the comet assay on both human cell lines, however no positive results were detected by bacterial assay, Ames test. The Tradescantia micronucleus assay showed increase in micronuclei formation for three samples. According to these results we can assume that the comet assay was the most sensitive assay, followed by the micronucleus test. The Ames test does not appear to be sensitive enough for water soil leachates genotoxicity evaluations where heavy metal contamination is anticipated.  相似文献   

18.
This paper presents a wireless, passive, remote query CO2 sensor comprising a ribbon-like magnetoelastic thick-film coated with a mass-changing CO2 responsive polymer synthesized from acrylamide and isooctylacrylate. In response to a magnetic field impulse, the magnetostrictive magnetoelastic sensor vibrates at a characteristic resonant frequency that is inversely dependent upon the mass of the attached CO2 responsive polymer. The mechanical vibrations of the magnetostrictive sensor launch magnetic flux, which can be detected remotely using a pickup coil. By monitoring the resonant frequency of the passive sensor, the atmospheric CO2 concentration can be determined without the need for physical connections to the sensor or specific alignment requirements. The effect of humidity and the CO2 responsive copolymer composition on the measurement sensitivity are reported. Greatest sensitivity is achieved with a polymer comprising a 1:1 mole ratio of acrylamide to isooctyl acrylate. A 0.7% change in atmospheric CO2 concentration can be detected for a 20 microns thick polymer coated sensor.  相似文献   

19.
微波消解-原子吸收光度法测定土壤中铜锌铅镉镍铬   总被引:24,自引:5,他引:24       下载免费PDF全文
用微波消解-原子吸收光度法测定土壤中铜,锌,铅,镉,镍和铬。通过硝酸-氢氟酸-过氧化氢体系消解液对土壤样品消解,选择出微波最佳消解条件。对硝酸-盐酸-过氧化氢体系消解液和硝酸-氢氟酸-过氧化氢体系消解液进行消解对比试验,发现前者不能将土壤样品完全消解,后者能将样品消解完全,但需将消解液中剩余的酸赶尽,否则测定结果将明显偏低。微波消解土壤与传统电热消解相比,操作简便快速,可提高工作效率。  相似文献   

20.
This paper reports the first results of geochemical survey carried out in and around Siddipet, taking soil (topsoil 0–25 cm and subsoil 70–95 cm) as the sampling media. The data were obtained in a consistent way from 61 sites. The samples were analyzed for 29 elements (As, Ba, Cd, Co, Cr, Cu, F, Mo, Ni, Pb, Rb, Se, Sr, Th, U, V, Y, Zn, Zr, Si, Al, Fe, Mn, Mg, Ca, Na, K, Ti, and P) by X-ray fluorescence spectrometer, and baseline levels for these elements are presented. Results reveal that the correlation between the geochemical patterns in the soils developed on different litho-variants is not straight forward, but some general trends can be observed. Regional parent materials and pedogenesis are the primary factors influencing the concentrations of trace elements while anthropogenic activities have secondary influence.  相似文献   

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