HPLC法测定多菌灵在西洋参中的残留量

本文报道了多菌灵在西洋参中残留量的HPLC检测方法.当添加水平在1.0一5.0μg·l~(-1)时,根中回收率为60一76%:添加水平在0.5一2μg·l~(-1)时,茎叶中回收率为70一80%;土壤添加2.5μg·l~(-1)时,回收率为84%.茎叶、根、土壤中残留量测定的相对标准偏差分别为2.16%.6.17%.1.24%.检测极限均为0.1μg·l~(-1)多菌灵在茎叶和土壤中的消解动态方程为C=118.42(?)和C=18.84(?)半衰期为5.87d和3.63d.     

Artificial indoor streams as a method to investigate the impact of chemicals on lotic communities

The potential hazard of chemicals on aquatic communities are generally evaluated by standardised single-species bioassays. Safety assessment is based on results gained from organisms adapted to lentic systems and biological interactions in ecosystems are neglected. While lotic communities are often at first in contact with chemicals, it is astonishing that microcosms with lentic communities are mainly used as a bridge between laboratory bioassays and outdoor aquatic systems. Hence, we established five artificial indoor streams to simulate abiotic factors of small rivers. The closed-circuit system was filled with nutrients added to tap water. Washed pebbles were used as sediment. The dynamics of a simple biocoenoses consisting of aufwuchs, Lumbriculus variegatus Asellus aquaticus and Gammarus fossarum was investigated. The dynamic of aufwuchs and periphyton was determined as dry weight and chlorophyll-a, respectively and qualitatively by pigment pattern. The abundance of different developmental stages of L. variegatus was determined at the end of the experiment as well as the population dynamics of G. fossarum and A. aquaticus. Survival rates of gammarids and juveniles per female were investigated and data were used for modelling the population dynamics. The experiment was carried out to investigate the performance of the established artificial streams and the developed approaches to investigate effects of chemicals on a basic lotic community. The prime reason to establish this approach was to close a gap between complex artificial stream systems and laboratory single species tests to assess the impact of chemicals on the aquatic environment.     

Photolytic degradation of fluoroquinolone carboxylic acids in aqueous solution

Subsequent to irradiation with a xenon lamp simulating sunlight, fluoroquinolone carboxylic acids in aqueous solution form polar pyridone dicarboxylic and tricarboxylic acids. After liquid/liquid partition with chloroform/water these substances can be isolated by ion exchange chromatography of the aqueous phase. They can be regarded as intermediate compounds on the route to a complete photomineralization. The structural elucidation is performed by such mass spectroscopic methods as MS, GC/MS and HPLC/MS, whereby HPLC/MS shows the highest reliability. Additionally¹H- and¹³C-NMR measurements confirm the structure of the main polar degradation product.     

可吸入尘中苯并（a）芘超声提取的高效液相色谱测定法

本文介绍一种简便、快速的可吸入尘中苯并(a)茈高效液相色谱测定方法.本法仅需5mL乙腈,超声处理10min即可完成提取过程.提取液离心后,上清液可直接进行HPLC分析.色谱条件:反相C18柱,用乙腈/水梯度洗脱,紫外检测器,λ=254nm.方法的最小检出量10~(-10)g.回收率95%,变异系数4、3%.此方法可用于大气可吸入尘中Bap的监测.     

Determination of selected neonicotinoid insecticides by liquid chromatography with thermal lens spectrometric detection

We studied the analysis of trace amounts of neonicotinoid insecticides by liquid chromatography coupled with a thermal lens spectrometric detector (TLS). This multi-residue analysis method is based on the reversed phase separation on C₁₈ column, isocratic elution and collinear dual beam TLS detection. The insecticides thiamethoxam, imidacloprid, acetamiprid and thiacloprid were detected with retention times of 4.4, 5.7, 6.5 and 8.5 min and limits of quantifications of 50, 89, 10, and 25 μg/L, respectively. The retention times agreed well with those obtained by the same chromatographic method but using a diode-array detector (DAD). The limits of quantifications for imidacloprid were identical in both techniques. However, the limits of quantifications for thiamethoxam, acetamiprid and thiacloprid were up to 8.5 times lower using the TLS detector compared to the diode-array detector. The applicability of the developed procedure was tested on spiked river water and potato samples.     

土壤中残留苯磺隆的高效液相色谱分析

本文报道了一种固相萃取净化，高效液相色谱测定土壤中苯磺隆的残留分析方法，不同土壤的添加回收率平均为８３．３％，８６．３％，７７．２％，线性范围２．５５－５１０ｎｇ，利用本法分析苯磺隆，精确、简便、快速。     

体外代谢系统中叶枯灵及其代谢产物的HPLC测定方法研究

采用三内标三波长切换技术建立了大鼠肝微粒体和肝细胞可溶部分孵育液中叶枯灵及代谢产物的HPLC测定方法.结果表明该方法所得样品萃取率较高,方法回收率和灵敏度也较高,方法重复性和精密度良好,为叶枯灵经体外的代谢提供了适用的定量研究方法.     

芳烃活度系数的测定及其在环境参数估算中的应用

采用反相高效液相色谱法间接测定了18种芳烃化合物的无限稀释活度系数(γ~-),并利用γ~-估算其辛醇/水分配系数、水溶解度、亨利定律常数,所得结果与文献值、计算值基本一致.     

高效液相色谱法测定多环芳烃化合物辛醇/水的分配系数及其对水溶解度的估算

本文采用反相高效液相色谱法间接测定了29种多环芳烃化合物的辛醇/水分配系数,并估算其水溶解度,所得结果与文献值和计算值基本一致。     

HPLC法测定废水中苯胺类化合物

用乙醚为提取有机相，提取前先经碱化，提取后加酸使苯胺成盐，吹去乙醚，用ＨＰＬＣ法测定苯胺类化合物。方法适用于测定废水中苯胺类化合物。检出限：苯胺３．０ｎｇ，邻硝基苯胺０．５ｎｇ，对硝基苯胺１．０ｎｇ。线性范围：苯胺０．８１７－１３．０７２μｇ／ｍｌ，邻硝基苯胺０．１４６４－２．３４２４μｇ／ｍｌ，对硝基苯胺０．２５３－４．０４８μｇ／ｍｌ。精密度（ＣＶ）：苯胺２．３８％，邻硝基苯胺１．０９％，对硝