固体吸附—4—氨基安替比林分光光度法测定空气中挥发酚

目前国内外现行的空气中酚类化合物测定方法主要采用色谱法和4-氨基安替比林分光光度法.在色谱法测定中已有不少研究者采用了固体吸附剂的采样方法.在4-氨基安替比林分光光度法中还未见有采用固体吸附剂采样的测定方法的报导.本文采用层析硅胶做空气中酚类化合物的固体吸附剂,以碳酸钠水溶液作为     

大气中沥青烟含量的分析方法研究——E_(1cm,λ(nm))~(1%)值法

大气中沥青烟含量已知的测定方法有重量法,紫外分光光度法——标准工作曲线定量法,以及HPLC法。这些分析方法,操作复杂,费时较长。由于沥青烟中多环芳烃的光化学分解作用,常使沥青烟标准品久置变质而影响分析结果的准确性,经常制备新鲜的沥青烟标准品,操作手续烦琐。为了简化分析手续,我们根据分光光度法定量分析的原理,在紫外分光光度法分析大气吸收液中沥青烟含量的基础上,采用称重法,配制沥青烟标准溶液,使其吸光度值在光度误差较小的范围     

跨界水体联合监测中总磷测定的问题探讨

研究了不同分析方法、去浊度手段和预处理方式对地表水总磷测定的影响。结果表明:钼酸铵分光光度法在跨界水体联合监测中较连续流动分析法、氯化亚锡还原光度法、孔雀绿-磷钼杂多酸分光光度法更为适用;在水样没有色度的情况下,采用浊度-色度补偿法和离心法都能有效消除浊度干扰,相对误差±10%;预处理方式的不同是导致各监测单位测定结果可比性差的最关键因素。     

一种用于光度法水质在线分析仪的温度自适应算法

分光光度法是用来测量待测物浓度的一种分析方法,在测量过程中,温度是影响测量结果的一个重要因素,提出了一种用于光度法水质在线分析仪的温度自适应算法,在0～40℃的温度范围内,浓度和吸光度的相关性系数都可以达到0.999以上,测量准确性可提高10%。     

用N-对辛基氧(代)苯甲酰苯基羟胺和苯基荧光酮萃取分光光度测定环境试样中的微量Ti(Ⅳ)

1. 前言 现在广泛应用过氧化氢法和二安替比林甲烷分光光度法测定Ti(Ⅳ)。然而,在测定环境试样中微量Ti(Ⅳ)时,必须开发灵敏度更高的分光光度分析方法。苯甲酰苯基羟胺(BPHA)及其衍生物是V(Ⅴ)的特效分光光度试剂,已众所周知。但是,BPHA在强盐酸酸性条件下也与Ti(Ⅳ)反应,生成黄色络合物而被有机溶剂萃取。利用这一反应,用BPHA及其衍生物分光光度测定Ti(Ⅳ)的报导较多。为了提高灵敏度,又进一步研究了Ti(Ⅳ)—BPHA—硫氰离子三元络合物的萃     

水和废水中总氮的现场快速分析方法研究

在现行水中总氮分析方法的基础上，利用便携式分光光度计和密封消解管，实验了过硫酸钾氧化、硫酸联氨还原、重氮－偶联反应的最佳条件，讨论了碱性过硫酸钾溶液用量及硫酸联氨溶液用量对分析结果的影响，从而建立了水体总氮的碱性过硫酸盐消解－分光光度分析方法，该方法可在现场简便快速地测定水和废水中的总氮。     

水和废水中亚硝酸盐氮的现场快速分析方法研究

在现行水中亚硝酸盐氮分析方法的基础上,通过试验研究,采用便携式分光光度计建立了水体中亚硝酸盐氮的分析方法。该法与GB7493-87[N-(1-萘基)-乙二胺光度法]具有良好的可比性,分析结果的精密度和准确度均为良好,该方法可在现场简便快速测定水和废水中的亚硝酸盐氮。     

黄河多泥沙水体油污染物的测定

研究了石油醚的吸收光谱 ,分析了泥沙对紫外分光光度法测定油污染物的影响 ,探讨了消除泥沙影响的方法 ,提出了紫外分光光度法测定黄河多泥沙水体中油污染物的改进方法。     

流动注射分光光度法测定水中六价铬的研究

研究建立了测定水中六价铬的流动注射光度分析方法,探讨了利用抗坏血酸的还原性扣除水样中轻度色度或浊度干扰的可行性.本方法线性关系好,检出限低,精密度和准确度高,对地表水、地下水、生活污水、工业废水等实样的测定获得了令人满意的结果.与传统的二苯基碳酰二肼分光光度法相比,具有方法简单、灵敏度高、分析速度快等优点,适用于环境监测的分析工作.     

紫外可见导数分光光度法在环境样品分析中的应用

环境样品,如水、气、土壤中有机和无机组分的测定,紫外可见分光光度法用得较为广泛。但许多化合物在紫外可见光区的吸收光谱非常相近,干扰物质的存在对谱线的分辨带来困难,若待测溶液浑浊则难以直接进行测定,必须辅以其它手段消除影响测定的因素,结果造成分析方法烦琐,费时。利用分光光度计的导数功能,把一般的吸收光谱对波长求导数,得到一条透过率或吸光度     

Multidimensional fluorescence studies of the phenolic content of dissolved organic carbon in humic substances

Indicators suggest that the amount of dissolved organic carbon (DOC) in natural waters may be increasing. Climate change has been proposed as a potential contributor to the trend, and under such a mechanism, the phenolic content of DOC may also be increasing. This study explores the assessment of the phenolic character of DOC using multidimensional fluorescence spectroscopy as a more convenient alternative to traditional wet chemistry methods. Parallel factor analysis (PARAFAC) is applied to fluorescence excitation emission matrices (EEMs) of humic samples to analyze inherent phenolic content. The PARAFAC results are correlated with phenol concentrations derived from the Folin-Ciocalteau reagent-based method. The reagent-based method reveals that the phenolic content of five International Humic Substance Society (IHSS) samples varies from approximately 5.2 to 22 ppm Tannic Acid Equivalents (TAE). A four-component PARAFAC fit is applied to the EEMs of the IHSS sample dataset and it is determined by PARAFAC score correlations with phenol concentrations from the reagent-based method that components C2, C3, and C4 have the highest probability of containing phenolic groups. The results show the potential for PARAFAC analysis of multidimensional fluorescence data for monitoring the phenolic content of DOC.     

Cyanotoxin management and human health risk mitigation in recreational waters

The occurrence and severity of harmful cyanobacterial or blue-green algal blooms (HABs) have increased in recent decades, posing a serious threat of illness to humans. In some countries, water contaminated with cyanotoxins that is used for drinking or haemodialysis has posed a particularly serious risk. However, it is now recognized that recreational exposure to natural toxins by skin contact, accidental swallowing of water or inhalation can also cause a wide range of acute or chronic illnesses. In this review, we focus on the importance of cyanotoxin management in recreational waters. The symptoms related with HAB poisonings, the recommended safety concentrations limit for cyanobacteria and cyanotoxins in such waters, as well as early health hazard indicators of their presence and their monitoring are all discussed. We also present in this review an overview of the methods developed in recent decades for eliminating cyanobacteria and the toxic compounds that they produce.     

Determination of arsenic content of some Romanian natural mineral groundwaters

Romania is one of the countries that have natural arsenic groundwater problems. This paper presents the results of a study of arsenic concentration monitoring in natural mineral waters collected from 23 sampling sites located in the northern, central, and western regions of Romania. The sampling sites are both natural springs and drilled wells. The graphite furnace atomic absorption spectrometry was used for arsenic content determination. The Piper??s classification principle was applied in order to find out the hydrochemical type of the analyzed waters. Depending on the concentration of arsenic, the water analyzed can be classified into three main categories: (1) mineral natural waters containing less than 10???g/L arsenic, (2) mineral natural waters containing arsenic at concentrations several times higher than the limit of 10???g/L but less than 100???g/L, and (3) mineral natural waters containing arsenic at concentrations of ten to a hundred times higher than the allowed limit of 10???g/L. The last-mentioned waters are of bicarbonatate sodium type and were sampled from seven sources only, being prohibited for human and animal use.     

Adsorption and detection of some phenolic compounds by rice husk ash of Kenyan origin

Rice husk ash (RHA) obtained from a rice mill in Kenya has been used as an inexpensive and effective adsorbent (and reagent) for the removal (and detection) of some phenolic compounds in water. The abundantly available rice mill waste was used in dual laboratory-scale batch experiments to evaluate its potential in: (i) the removal of phenol, 1,3-dihydroxybenzene (resorcinol) and 2-chlorophenol from water; and (ii) the detection of 1,2-dihydroxybenzene (pyrocatechol) and 1,2,3-trihydroxybenzene (pyrogallol) present in an aqueous medium. The studies were conducted using synthetic water with different initial concentrations of the phenolic compounds. The effects of different operating conditions (such as contact time, concentration of the phenolic compounds, adsorbent quantity, temperature, and pH) were assessed by evaluating the phenolic compound removal efficiency as well as the extent of their color formation reactions (where applicable). RHA exhibits reasonable adsorption capacity for the phenolic compounds and follows both Langmuir and Freundlich isotherm models. Adsorption capacities of 1.53 x 10(-4), 8.07 x 10(-5), and 1.63 x 10(-6) mol g(-1) were determined for phenol, resorcinol and 2-chlorophenol, respectively. Nearly 100% adsorption of the phenolic compounds was possible and this depended on the weight of RHA employed. For the detection experiments, pyrocatechol and pyrogallol present in water formed coloured complexes with RHA, with the rate of colour formation increasing with temperature, weight of RHA, concentration of the phenolic compounds and sonication. This study has proven that RHA is a useful agricultural waste product for the removal and detection of some phenolic compounds.     

Occurrence of estrogenic chemicals in South Korean surface waters and municipal wastewaters

Broad scale monitoring of estrogenic compounds was performed at 19 sampling points throughout the Yeongsan and Seomjin river basins and 5 wastewater treatment plants (WWTPs) adjacent to the Gwangju area, Korea, from December 2005 to August 2007. The concentrations of estrogenic compounds, including estrone (E1), 17β-estradiol (E2), 17α-ethynylestradiol (EE2), bisphenol-A, nonylphenol (NP) and 4-octylphenol (OP), in the samples was measured with gas chromatography/mass spectrometry (GC-MS). In addition, the estrogenic activities throughout the river were investigated using the E-screen assay. Of the six estrogenic chemicals, NP (114.6-336.1 ng L(-1)) and EE2 (0.23-1.90 ng L(-1)) were detected at the highest and lowest levels, respectively in both the river waters and the WWTP effluents. Bisphenol-A showed the largest concentration range, from 7.5 to 335 ng L(-1). The concentrations of E1, E2 and octylphenol ranges were 3.6-69.1, 1.2-10.7, and 2.2-16.9 ng L(-1), respectively. According to the calculated estradiol equivalent concentration (EEQ); however, no estrogenic contribution was observed due to the phenolic compounds in the river waters and effluents. E1 and E2 dominated in both the river water and effluent samples, with contributions to the calculated EEQ of over 79 and 77%, respectively. Conversely, EE2 was rarely detected in the river waters (21%) and effluents (0%). The largest contribution of EE2 to the calculated EEQ was 21% in the river water at S-7. The levels of E1, E2, and EE2 were remarkably decreased in the effluents, indicating that the 5 WWTPs did not contribute to the estrogenic effect of the receiving streams. Overall, the WWTPs did not contributed to the estrogenic activity of the receiving waters, but the livestock industry or wildlife may play an important role in the estrogenic contribution to river water.     

Monitoring priority substances of directives 76/464/EEC and 2000/60/EC in Greek water bodies

The priority substances of List I, 76/464/EEC Directive, some of which belong to the new Water Framework Directive 2000/60/EC, have been monitored in the surface waters of Greece through the developed network of 53 sampling stations. The analytical methods used for the determination of these substances included Purge and Trap-Gas chromatography-Mass spectrometry for volatile and semivolatile organic compounds, Gas Chromatography-Electron Capture Detection for organochlorine insecticides, High Performance Liquid Chromatography for pentachlorophenol and Atomic Absorption Spectrometry for metals. The results have shown the presence of several priority substances in Greek surface waters, in most cases at concentrations well below the regulatory limits. However, non-compliance was observed for a limited number of compounds. The monitoring network and the analytical determinations have to be expanded to more water bodies and more priority substances, in order to safeguard the quality of Greek surface waters.     

酚类物质的3种衍生方法比较研究

对3类适用于酚类物质的衍生方法进行比较。结果显示,3种衍生方法均具有改善峰形、提高检测灵敏度、降低检出限等优势。其中七氟丁酸酐衍生法具有较大的腐蚀性;TMS衍生体系对水分非常敏感,需确保衍生体系脱水充分;五氟苄基溴衍生相对更成熟和完善。     

Thermogenic hydrocarbons in seawater of the Gippsland Shelf,southeast Australia

An offshore survey measured the concentration of thermogenic hydrocarbons (THCs) in samples extracted from seawater at 718 locations along 22 traverse lines across the Gippsland Shelf, southeast Australia, and recorded compounds typical of subsurface crude oil and natural gas (petroleum) accumulations. Background concentrations of 8 ppm, with isolated peak levels of 20 to 52 ppm, were detected in samples extracted from seawater at depths of 30 to 50 m over distances of 10 km. Two sources have been suggested — seepage of THCs from subsurface accumulations of petroleum, or THCs in waste-water discharged by several offshore petroleum production facilities which are present on the shelf. A waste-water source is favoured because of the transitory nature of the concentrations, and changes in composition consistent with plume drift away from the point(s) of discharge. Overall, however, the concentration of THCs in waters of the Gippsland Shelf compare favourably with levels in waters affected by urban runoff. The concentration of THCs in other coastal waters from urban and onshore sources is low, equivalent to the background concentration in the major oceans of the world.     

Validation of plant based bioassays for the toxicity testing of Indian waters

Plant-based bioassays have recently gained remarkable popularity among the toxicological/eco-toxicological assessment procedures. The reasons for their wide use are comparative simplicity, sensitivity, and cost-effectiveness as well as a good correlation with other toxicity tests. The present study describes the use of two plant bioassays, Allium cepa test and seed germination test in the evaluation of the toxicity/genotoxicity of industrial waste water and river water and standardization with the commonly occurring pollutants in Indian waters namely heavy metals and phenolics. Both tests were standardized to suit the Indian conditions, and the local varieties were used. Both bioassays responded significantly with the test range of heavy metals and phenolics. The toxicity of heavy metals was in the order of Cu > Ni > Cd in both the tests whereas 2,4-dinitrophenol was the most toxic among the phenolic compounds. Cabbage, millet, and cucumber, respectively, were found to be the most sensitive in the seed germination test for the test heavy metals and phenols. Significant amounts of chromosomal abnormalities including bridges, stickiness, and fragmentations were recorded with both the industrial waste water and the XAD concentrated river water samples by A. cepa test.     

水中多种酚类化合物衍生化方法研究

对水中14种酚类化合物的衍生化过程进行研究，选取不同衍生化试剂、衍生温度和衍生时间、最大衍生量等多个对衍生效率有决定性影响的参数进行优化。通过上述条件的优化选择，实现了对苯酚、氯代酚、甲基酚和硝基酚等14种不同类型酚类化合物最优的衍生化，衍生效率达到75．5％～119％。