微波消解/电感耦合等离子体质谱法测定垃圾焚烧飞灰中稀土元素

建立了微波消解/电感耦合等离子体质谱法(ICP-MS)测定生活垃圾焚烧飞灰中15种稀土元素含量的方法。通过采用HNO_3-HCl-HF混合酸/微波消解体系对飞灰进行前处理,利用ICP-MS测定稀土元素,有效降低了多原子离子的质谱干扰;在线加入~(103)Rh内标元素进行校正,有效消除了非质谱干扰,使测试结果更加准确。15种稀土元素检出限均为0.000 2～0.004 3 mg/kg,方法的精密度(RSD,n=6)为0.94%～2.86%。     

微波消解-ICP-MS测定彩妆类化妆品17种禁用重金属元素

考察彩妆类化妆品中锑、砷、铍、铬、钴、镍、钒、金、铅、硒、锶,蹄、铊、汞、镉、钡、钕17种禁用重金属元素的残留量。建立用微波消解-电感耦合等离子体质谱仪(ICP-MS)同时测定彩妆类化妆品中17种重金属的方法。针对分析过程中基体效应质谱干扰,在MS/MS模式下,向碰撞反应池通入氦气,采用质量碰撞消除质谱干扰,同时在线引入锂、钪、铋、铟、锗、铑作为内标校正基体效应,稳定质谱信号。结果表明,在优化仪器的条件下,各元素线性关系良好,相关系数均大于0.999,检出限范围：0.015mg/kg～0.0427 mg/kg;精密度范围：1.2%～6.1%;加标回收：91.2%～108.0%。结论：该方法具有灵敏度高、简便、同时测定的特点,能准确测定彩妆类化妆品重金属元素含量。     

全自动石墨炉消解-电感耦合等离子体串联质谱测定土壤中的镉

建立全自动石墨炉消解-电感耦合等离子体串联质谱测定土壤中镉的方法。实验表明，以¹⁰³Rh作为内标，O₂模式下用电感耦合等离子体串联质谱测定镉，方法线性良好，线性相关系数0.999 9,方法检出限0.003 mg/kg,测定下限为0.012 mg/kg。检测有证标准土壤验证方法准确性，结果显示，测定值均在标准允许误差范围内，相对标准偏差在1.4%～3.4%。结果表明，用O₂作为反应气体，串联四级杆质谱仪作为检测器能有效消除土壤杂质的干扰。对比现有国标测定土壤中镉的方法，该方法是一种更加快速、准确、可大批量处理土壤中镉的检测方法。     

饲料中铝检测方法的建立与评价

旨在建立高效的测定饲料中铝含量的测定方法。样品预处理采用微波消解法，主要从试验结果对空白值测定及校准曲线的绘制、精密度的测定、回收率的测定这几方面进行研究，确定最适合测定饲料中的铝含量的分析方法为电感耦合等离子体发射光谱法。按照电感耦合等离子体发射光谱法测定样品中铝，结果在0～5 mg/L质量浓度范围内线性关系良好(r≥0.999 9),检出限为0.057 mg/L,定量限为0.171 mg/L,相对标准偏差(RSD,n=7)为0.6%,小于5%;回收率在96.4%～104.4%,测定结果准确。结果表明，研究建立的电感耦合等离子体发射光谱法准确度高，精密度好，方法可靠，可作为准确、快速检测饲料中铝含量的方法。     

ICP-AES法测定绿茶中镍含量

为监测绿茶中污染元素镍分布范围,本文采用微波消解方法,以电感耦合等离子体发射光谱仪(ICP-AES)测定绿茶样品中镍含量。方法线性关系良好,经国家标准物质GBW10052验证,结果稳定可靠。方法检出限为9μg/L,相对标准偏差为1. 6%,加标回收率为96. 3%～100. 6%。测定了11个绿茶样品,得到镍含量范围为1. 75～16. 02 mg/kg,其中有1个样品镍含量达到16. 02 mg/kg,明显大于其他样品。     

聚氯乙烯食品包材中稀土元素测定方法研究

基于现有食品接触材料聚氯乙烯(PVC)中稀土元素含量测定方法的空白,对其开展了研究。以不同的消解方法为前处理手段、以电感耦合等离子体质谱(ICP-MS)为检测手段,测定不同类型PVC食品接触材料中稀土元素的含量。四氢呋喃溶解法测得的稀土元素的效果最好,在质量浓度为0.1～100μg/L时呈良好的线性关系,检出限为0.015～0.030 mg/kg。应用该方法测定PVC食品包材中稀土元素的含量,加标回收率范围为93.3%～109.1%。该方法对食品包材中稀土元素的痕量检测具有一定的应用前景。     

电感耦合等离子体质谱法测定明胶中铬

建立一种用电感耦合等离子体质谱法测定明胶中铬的分析方法。用微波消解法进行前处理,以Rh作为内标,用电感耦合等离子体质谱法(ICP-MS)法测定明胶中的铬。结果显示,Cr在0～40μg/L范围内呈线性关系,其线性相关系数R=0.9994,加标回收率为91.62%～94.85%,相对标准偏差为0.789%,明胶中铬含量为1.3593 mg/kg。本方法快速,简便,精密度符合检测要求,适用于明胶中铬的测定。     

ICP法测定土壤中4种痕量重金属元素实验研究

采用石墨消解仪对土壤进行前处理,建立电感耦合等离子体发射光谱法同时测定土壤中铍、锑、钼、银等4种痕量重金属元素含量的方法。该方法相关系数均在3个9以上,测定国家标准物质土壤样品,测定值与保证值一致,相对标准偏差0.3%～11.5%,检出限为0.005～0.1 mg/kg,加标回收率为87%～95%。     

电感耦合等离子体发射光谱法测定皮革中的六价铬

建立了电感耦合等离子体发射光谱法(ICP)测定皮革中六价铬的方法。使用国际通用的前处理方法制备皮革萃取液,然后用聚氯化铝(PAC)絮凝剂将萃取液中的三价铬沉淀分离后,使用电感耦合等离子体发射光谱仪测定溶液中的六价铬。本方法操作简单,线性范围在0.2~10mg/L,相关系数为0.9999,检出限为0.9 mg/kg,回收率大于95%,准确性和精密度良好。     

气相色谱-质谱/质谱联用法测定橡胶中的乙酰苯

建立了气相色谱-质谱/质谱联用法测定橡胶材料中乙酰苯的方法。样品用叔丁基甲醚超声提取,用气相色谱-质谱/质谱联用仪检测,该方法线性范围0.01～1.0μg/mL,相关系数r=0.9996,检出限0.1mg/kg,回收率为88%～102%。     

佛山市顺德新城区降水中污染物的监测和分析

为掌握佛山市顺德新城区降水中污染物的情况,2015年7月至8月,文章作者分别在雨天进行了降水取样,对降水中的pH、电导率、常见阴离子(F-、Cl~-、NO_3~(2-)、SO_4~(2-))及部分重金属(铅和镉)进行监测分析。选择有相关数据的珠江三角洲和石家庄、厦门等地的降水中污染物的情况进行对比。结果表明,顺德新城区降水中的p H和部分阴离子浓度优于珠江三角洲平均值,酸雨类型属于硫酸和硝酸混合型;其水体洁净程度略差于石家庄;铅和镉的浓度也高于厦门,甚至部分超出了人体能直接接触的安全范围。     

Metabolism of trideuterated iso-lignoceric acid in rats in Vivo and in human fibroblasts in culture

Saturated very long chain fatty acids (fatty acids with greater than 22 carbon atoms; VLCFA) accumulate in peroxisomal disorders, but there is little information on their turnover in patients. To determine the suitability of using stable isotope-labeled VLCFA in patients with these disorders, the metabolism of 22-methyl[23,23,23-²H₃]tricosanoic (iso-lignoceric) acid was studied in rats in vivo and in human skin fibroblasts in culture. The deuterated iso-VLCFA was degraded to the corresponding 16- and 18-carbon iso-fatty acids by rats in vivo and by normal human skin fibroblasts in culture, but there was little or no degradation in peroxisome-deficient (Zellweger’s syndrome) fibroblasts, indicating that its oxidation was peroxisomal. Neither the 14-, 20-, and 22-carbon iso-fatty acids nor the corresponding odd-chain metabolites could be detected. In the rat, the organ containing most of the iso-lignoceric acid, and its breakdown products, was the liver, whereas negligible amounts were detected in the brain, suggesting that little of the fatty acid crossed the blood-brain barrier. Our data indicate that VLCFA labeled with deuterium at the ω-position of the carbon chain are suitable derivatives for the in vivo investigation of patients with defects in peroxisomal β-oxidation because they are metabolized by the same pathways as the corresponding n-VLCFA. Moreover, as iso-VLCFA and their β-oxidation products are readily separated from the corresponding n-fatty acids by normal chromatographic procedures, the turnover of VLCFA can be more precisely measured. A preliminary report of part of this work (Reference 18) was presented at the 5th International Symposium on the Synthesis and Applications of Isotopes and Isotopically Labelled Compounds, Strasbourg, France, June 20–24, 1994.     

高效液相色谱法分析化妆品中微量成分的研究进展

综述了高效液相色谱法在化妆品中防腐剂、防晒剂中紫外线吸收剂以及性激素的检测等几个方面的应用;同时,介绍了分析所用的色谱柱、流动相、使用的检测手段以及样品的提取方法;最后针对目前存在的问题,提出了高效液相色谱用于化妆品中微量成分分析的研究方向和发展前景。     

Denitrification in shallow groundwater in a coastal agricultural area in Japan

In a coastal agricultural area in the central part of Japan (Shizuoka), we found decreasing nitrate concentration with depth in a shallow groundwater, where the depth to water table varied between 0.6 and 1.2 m below ground surface. High nitrate concentrations (5–29 mg N L^–1) were often observed in the upper layer (0–2 m) of the groundwater, but the concentration decreased to less than 1 mg N L^–1 in the deeper layer. Ammonium was scarcely detected, and the concentration of dissolved oxygen was usually low (< 1 mgO₂ L^–1) in the groundwater. Nitrate in the groundwater often had very heavy nitrogen stable isotope ratios (>20{}). There was a negative relationship between nitrogen stable isotope ratio of nitrate and its concentration. When nitrate was injected into the groundwater with acetylene and bromide (a conservative tracer), nitrate concentration decreased to 20% of the initial level within 5 days, accompanied by the increase in nitrite and nitrous oxide concentration and a little change in bromide concentration. These results indicate that microbial denitrification plays a potential role in the decrease of nitrate in shallow groundwater at the study site.     

我国硝酸工业生产技术新进展

系统叙述了我国硝酸工业2000-2007年生产现状及主要技术成果,尤其指出了国产"四合一"机组的成功投运,使我国硝酸国产化装置取得较大的进步,表现在吨酸的铂耗、氨耗和能耗等方面接近国外引进装置水平,同时介绍了国外双加压法硝酸生产技术的进展.我国已成为硝酸生产大国,仍需以先进的技术改造和发展我国硝酸工业,确保我国硝酸工业健康有序地发展,加快从硝酸生产大国向强国迈进的步伐.