在线固相萃取-高效液相色谱法测定饮用水和瓶装矿泉水中苯酚

苯酚类化合物是一种水体污染物,欧盟规定饮用水中每种苯酚类化合物的限量为0.5μg·L-1,日本厚生劳动省（Ministry of Health,Labour and Welfare）规定饮用水中苯酚类化合物的含量不得高于5μg·L-1     

不同土壤层中4种菊酯类农药残留量的测定

采集农田中表层、里层、深层土壤,采用正己烷 ∶ 丙酮＝1 ∶ 1(V/V)作为提取剂^[1,2],土壤样品于Florisil柱中净化,浓缩定容后,用电子捕获检测器检测,石英毛细管柱气相色谱法测定,用外标法定量。以农田表层土壤测定结果为例,甲氰菊酯的回收率为85.2%~102.7%,RSD为2.27%~5.41%;氯氰菊酯的回收率为80.5%~102.7%,RSD为2.84%~6.70%;氰戊菊酯的回收率为80.2%~103.0%,RSD为2.33%~5.95%;溴氰菊酯的回收率为80.8%~102.7%,RSD为2.45%~6.24%。方法简便、快速、成本低。     

高效液相色谱法测定水中甲醛

以2,4-二硝基苯肼(2,4-DNPH)为衍生试剂,在柠檬酸-柠檬酸钠缓冲溶液(pH值约为3)条件下,使甲醛转化为相应稳定的甲醛-2,4-二硝基苯腙,0.45 μm过滤头过滤后,在360nm处紫外检测,其检出限5.0μg/L,加标回收率为88.0％～115％.     

饮用水源水中丙烯醛测定方法改进

对饮用水源水中丙烯醛的气相色谱标准测定方法作了改进,由直接进样改为吹扫捕集进样,由极性色谱柱改为中等极性色谱柱.方法在0.010 mg/L～0.100 mg/L范围内线性良好,最低检出限和检测下限分别为0.000 5 mg/L和0.002 mg/L,水样平行测定的RSD为2.8%～5.2%,平均加标回收率为90.0%～...     

液液萃取-高效液相色谱法测定水中四乙基铅

采用高效液相色谱紫外检测器测定水中四乙基铅,用二氯甲烷液液萃取,以甲醇/水混合溶液(体积比为95:5)为流动相,Z0RBAX Eclipse XDB-C18色谱柱分离,选择测定波长为280 nm.方法在0.100mg/L～1.00mg/L范围内线性良好,检出限和测定下限分别为0.01μg/L和0.04μg/L,水样平行...     

气相色谱法同时测定地表水中的百菌清、环氧七氯和有机氯农药

用正己烷一次同时萃取地表水中的百菌清、环氧七氯和有机氯农药,萃取液脱水后进气相色谱仪进行测定。当取样体积为500ml时,方法检出限为0．01～0．02μg,／L,标准曲线相关系数大于0．999,方法精密度的相对标准偏差为1．5％-4．0％,加标回收率为81．6％～109．6％。该方法用于实际样品测定,结果令人满意。     

毛细管柱气相色谱法测定环境空气中的樟脑

采用毛细管柱气相色谱氢火焰离子化检测器测定环境空气中的樟脑,选择硅胶为吸附剂,甲醇/丙酮混合溶剂(体积比90∶10)为解析剂.方法在0.544 mg/L～109 mg/L范围内线性良好,检出限为0.06 mg/L,当采样体积为20 L时,最低检出质量浓度为0.003 mg/m3,标准溶液平行测定的RSD≤3.8％,空白...     

烘箱加热—碱性过硫酸钾消解—离子色谱法分析水中总氮

总氮是地表水监测的指标,目前采用的方法是碱性过硫酸钾消解—紫外分光光度法。该法操作繁琐,空白值较高及选择性较差。笔者在参考有关文献的基础上,研究了烘箱加热—碱性过硫酸钾消解—离子色谱法测定水中总氮,结果表明,该法操作简便,选择性好,测定精密度和准确度满足要求,表明该方法测定结果可靠,具有一定的应用价值。     

Biodegradation of organochlorine pesticide endosulfan by bacterial strain Alcaligenes faecalis JBW4

The recently discovered endosulfan-degrading bacterial strain Alcaligenesfaecalis JBW4 was isolated from activated sludge. This strain is able to use endosulfan as a carbon and energy source. The optimal conditions for the growth of strain JBW4 and for biodegradation by this strain were identified, and the metabolic products of endosulfan degradation were studied in detail. The maximum level of endosulfan biodegradation by strain JBW4 was obtained using broth at an initial pH of 7.0, an incubation temperature of 40℃ and an endosulfan concentration of I00 mg/L. The concentration of endosulfan was determined by gas chromatography. Strain JBW4 was able to degrade 87.5% of α-endosulfan and 83.9% of β-endosulfan within 5 days. These degradation rates are much higher than the previously reported bacterial strains. Endosulfan diol and endosulfan lactone were the major metabolites detected by gas chromatography-mass spectrometry; endosulfan sulfate, which is a persistent and toxic metabolite, was not detected. These results suggested that A. faecalis JBW4 degrades endosulfan via a non-oxidative pathway. The biodegradation of endosulfan by A. faecalis is reported for the first time. Additionally, the present study indicates that strain JBW4 may have potential for the biodegradation of endosulfan residues.     

离子色谱法同时测定饮用水中的5种无机阴离子

研究了利用直接电导检测-离子色谱法同时测定饮用水中5种无机阴离子(F-、Cl-、SO42-、NO3-、NO2-)的方法,实验采用IonPacAS11(4 mm×250 mm)阴离子交换分离柱,选用KOH为淋洗液,考察了淋洗液浓度、流速及柱温对上述无机阴离子的影响。确定最佳色谱条件为:以23.0 mmol/L KOH为淋洗液,流速1.2 mL/min,柱温31.0℃。在此条件下可同时分离和测定五种无机阴离子,且色谱峰形对称。离子浓度的相对标准偏差(RSD,n=4)在0.14%~1.78%之间,相对误差在0.72%~3.17%之间,加标回收率在97.5%~105.0%之间,能在9 min内完成分析。方法简便、快速,检测结果准确可靠,用于实际饮用水分析,所得结果令人满意。