稀盐酸溶液吸收—气相色谱法测定环境空气中的痕量三乙胺

以稀盐酸为吸收液，用气相色谱法测定环境空气中痕量三乙胺，结果表明0．1mol／LHCL和0．2mol／LHCL是环境空气中痕量三乙胺的有效吸收液，吸收后样品稳定性良好。在优化的色谱条件下，气相色谱直接进样，FID检测器测定吸收液中的三乙胺线性好、操作简便、精密度高、检出限低，回收率符合要求。     

工业废水中氯苯等6种有机污染物的RP-HPLC分离检测

采用反相高效液相色谱法同时测定了氯苯等 6种有机污染物 ,对影响分离测定的诸因素进行了研究 ,建立了最佳色谱分离条件 ,并用于工业废水中有机污染物分析 ,回收率在 97%～ 10 3 %范围内     

加速溶剂提取-气相色谱法测定蔬菜中的有机氯农药

加速溶剂提取技术萃取蔬菜样品中的有机氯农药残留具有萃取速度快、溶剂用量少、选择性高等优点。用加速溶剂提取-气相色谱法测定蔬菜中的有机氯农药残留,其结果与国标法(GB/T5009,19-1996)和美国EPA法(3545)进行比较。结果表明:加速溶剂提取-气相色谱法能够对蔬菜中多种有机氯农药残留的提取和测定达到很好的效果,蔬菜中12种有机氯农药在两种质量分数(25和100ng·g-1)的添加的回收率在80%和125%之间,高于国标法,而与美国EPA的方法相当。用此法对南京市郊蔬菜中有机氯农药残留状况进行分析表明:南京市郊蔬菜中有机氯农药的检出率在76%和100%之间,DDTs是蔬菜中的主要有机氯农药残留,其次为六六六,分别占残留总量的48.5%~74.6%和14.0%~27.9%。10种试验蔬菜体内DDT和六六六的残留量均不超标,但此类物质可在食物链中富集和放大,仍会对农产品质量和人体健康构成潜在威胁。     

硅胶色层分析土壤中水溶性腐殖酸

采用水浸取法和硅胶色层法，通过紫外吸收光谱峰定性鉴定了英格兰七种土壤水溶性腐殖酸。沉积土中水溶性腐殖酸均展示了二组峰值，而在草原土中低分子量组份消失。选用γ谱仪测定了沉积土水溶性腐殖酸中的放射性核素^137Cs，采用中子活化测量技术分析了常量钠和氯。结果表明，在高盐含量的沉积土中存在的大量竞争络合离子钠可能是使放射性核素^137Cs与沉积土中水溶性腐殖酸没有直接关系的原因。     

Role of heavy polar organic compounds for water repellency of sandy soils

Separation and chemical characterisation of specific compounds responsible for soil water repellency has not previously been achieved. Here we describe the extraction, separation and analysis by gas chromatography-mass spectrometry of organic compounds found in wettable and water repellent sandy soils from the Netherlands and United Kingdom. Fatty acids (C₁₆–C₂₄), amides (C₁₄–C₂₄), alkanes (C₂₅–C₃₃), aldehydes/ketones (C₂₃–C₃₁) and complex ring-containing structures were detected in all samples. We found a greater abundance of high molecular mass polar compounds in the water repellent samples.     

顶空-气相色谱法测定水中溴乙烷

建立了顶空-气相色谱法测定环境中不同基质水样中溴乙烷的方法,分别考察了顶空平衡温度、平衡时间、离子强度对溴乙烷富集的影响,从而确定最佳方法参数。结果表明,溴乙烷在0. 10~10. 0μg/L范围内线性关系良好,相关系数(r)为0. 999 0,检出限为0. 012μg/L,测定下限为0. 048μg/L,加标回收率为86. 7%~104. 7%,相对标准偏差(RSD)为2. 9%~4. 8%。该方法准确度和精密度高、检出限低,能够满足环境中不同基质水样中溴乙烷的检测要求。     

Investigation of pesticide residues in water,sediments and fish samples from Tapi River,India as a case study and its forensic significance

Abstract

This research is a case study on detection of pesticides in river water, sediment as well as fish samples from Tapi River, among the major rivers of Gujarat, India. To investigate the misuse, concentration level and occurrence patterns of persistent pesticides, samples were collected from the river. Chlorpyrifos, methyl parathion, hexachlorocyclohexane (HCH), dichloro diphenyl trichloroethane (DDT) and endosulfan were analyzed by gas chromatography technique with flame ionization detector (FID). Scanty reports are available, but after 1999, no such data are reported as some of these pesticides have been banned. Although these pesticides are still in use which we observed from the obtained results. In this river, the amount of endosulfan, chlorpyrifos, and methyl parathion was observed in surface water with concentrations of 37.56?µg/L, 0.86?µg/L and 0.43?µg/L, respectively. Endosulfan, DDT and methyl parathion detected in sediment were 38.38?ng/g, 0.65?ng/g and 0.77?ng/g, respectively. In fish samples, levels of endosulfan, chlorpyrifos, and methyl parathion detected were 101.28, 0.392, and 3.49?ng/g correspondingly. Results showed that highly toxic pesticides are still being used in the surrounding area, and there is an urgent need for enforcement of rules to control the production and application of such pesticides.     

短柱气相色谱法研究焚烧炉飞灰上萘的氯化反应及其产物

本文用0.3mBenton-34/OV-1短填充柱气相色谱法研究了萘在焚烧炉飞灰上的氯化反直产物,实验表明,飞灰表面性质对氯化有促进作用,这种促进作用与飞灰的来源或表面性质有强烈关系,文中对有关分析方法和萘在焚烧炉飞灰上氯化反应的结果作了讨论。     

水中痕量二乙三胺的气相色谱分析

本文提出水中痕星二乙三胺（ＤＥＴＡ）的气相色谱分析方法,应用甲基化试剂,将水中的二乙三胺直接转化成Ｎ,Ｎ,Ｎ‘,Ｎ’,Ｎ“－五甲基二乙三胺（ＭＤＥＴＱＡ）,萃取后经ＦＩＤ检测,最低检测限可达１ｐｐｍ,以１,６－已胺ＨＤＡ为内标物对二乙三胺进行定量,相对偏差小于１０％。     

低压离子色谱法测定水和酸雨样品中F~-,Cl~-,NO_3~-,SO_4~(2-)离子

本文介绍了低压离于色谱法测定水样(井水、湖水、矿泉水、自来水)和酸雨中氟、氯、硝酸根、硫酸根离子的方法.欲测阴离子在阴离子交换柱上被分离,同时用1.2mol·l~(-1)N_2CO_3溶液作流动相,流速为 1.6ml·min~(-1).各离子的流分用电导检测.进样量为50μl时F~-,Cl~-,NO_3~-,SO_4~(2-)的最低检出限(2倍噪音比)分别为10,20,250,500ng·ml~(-1).