摘要

摘要：研究了不经基体分离，膜去溶一ICP MS法直接测定高纯CeO2中14种痕量稀土杂质的分析方法，讨论了ce基体产生的多原子离子对被测元素的质谱干扰，并且对影响多原子离子产率的因素进行了分析，同时建立了Pr，Gd，rrb和Yb数学校正方程。通过使用膜去溶雾化器和优化ICP．MS参数，消除了Cel ，CeO2 和CeO2H 产生的质谱干扰，将CeO／Ce产率降为0．008％ ，同时结合数学校正方程彻底消除了CeO ，CeOH 和CeOH2 的质谱干扰。Pr，Gd，，rb和Yb的方法测定下限分别为0．08，0．1，0．15和0．008 g·g～ ，l4种稀土杂质方法测定下限和为0．75 g·g一。99．999％高纯CeO2实际样品测定加标回收率为96％ ～103％ ，RSD为1．2％ ～4．3％ 。 关键词：高纯CeO ；膜去溶；数学校正；ICP．MS；多原子离子干扰；稀土

摘要

摘要：灵敏地检测了高纯钨粉中的痕量金属杂质。钨粉用 02溶解后进入离子色谱的阳离子交换柱，经水淋洗后，用HN03洗脱，洗脱后的溶液经过膜去溶装置雾化去溶后进入电感耦合等离子体质谱检测。除B，V，Sb外，其它杂质元素如Mg，Al，Ti，Cr，Be，Fe，Mn，c0，Ni，cu，zn，Ga，Sr，Cd，Ba等的回收率均在90％ 一107％之间，检出限在0．0ol～0．5 gg／g之间。 关键词：痕量元素；高纯钨粉；离子色谱；阳离子交换柱；膜去溶装置；电感耦合等离子体质谱

摘要

Abstract: In this work we have developed a cost-effectivemethod for the analysis of methyl mercury (MeHg) inseawater fish muscle. The novelty of this method lies in theuse of microwave- assistedextraction with acidic solution (HCl), addition of toluene, and subsequent extraction with cysteine acetate solution where only MeHg is present because of its affinity for cysteine groups. MeHg in cysteine phase and total mercury in the homogenate muscle tissue were determined using a direct Hg analyzer (DMA-80). Validation, precision, and accuracy of the methodwere evaluated and monitored with a tuna fish certified reference material (CRM 463) containing MeHg. Keywords Methyl mercury
Microwave extraction
Mercury
Direct mercury analyzer

摘要

Chiara Maggia, Maria Teresa Berduccia, Jessica Bianchia,∗, Michele Gianib, Luigi Campanellac a Advanced Institute for Environmental Protection and Research – ISPRA, Via di Casalotti 300, Rome, Italy b National Institute of Oceanography and Experimental Geophysics, Biological Oceanography Department, Via Piccard 54, 34100 Trieste, Italy c Chemical Department University “La Sapienza”, P.le Aldo Moro 5, 00185 Rome, Italy

摘要

The specific aim for this ongoing study is todetermine whether female subjects (18-40years of age, target=120) who enroll in the study with elevated hair mercury levels(>0.8 ppm) and are then fed low mercuryfish (farmed salmon or farmed tilapia at 6 ounces [170g]/week for 12-13 weeks),while avoiding other seafood, willsignificantly decrease their hair and bloodmercury concentrations while maintainingor increasing their plasma omega-3 fattyacid (EPA/DHA) levels.

摘要

对羟基苯甲酸酯是一类新一代高效低毒消毒杀菌防腐剂，它的抗菌能力比苯甲酸和山梨酸及其盐类强，应用pH范围比苯甲酸和山梨酸及其盐类广，用量比苯甲酸和山梨酸及其盐类低得多，并且使用安全，经济方便，对人体刺激较小。作为食品防腐剂，这类物质可用于饮料、果蔬加工品、海产加工品、禽畜加工品、调味品、啤酒、米酒等加工品中，还可用于水果、蔬菜和海产品的防腐保鲜。其生产过程需要提纯。

摘要

类胡萝卜素是一类重要的天然色素的总称，即普遍存在于动物、高等植物、真菌、藻类和细菌中的黄色、橙红色或红色的色素，包括-胡萝卜素，-胡萝卜素，-胡萝卜素和叶黄素等结构相似的化合物。营养学上，当有需要时，人体会将-胡萝卜素转换成维他命A，因此被广泛用作食品色素，也出现不少含有胡萝卜素的营养品。由于其结构的相似性，对各种单一组份的分离提纯会相对困难，而循环制备液相色谱就成为一种很好的类胡萝卜素分离方式。

摘要

Precise and rapid determination of total mercury in Shampoo can be performed using Direct Mercury Analyzer. Such an instrument requires no sample wet chemistry or pretreatment. Once a weighed sample portion is introduced into the instrument, analysis is complete in six minutes. Direct analysis of mercury, using the integrated sequence of Thermal Decomposition, Catalyst Conversion, Amalgamation, and Atomic Absorption Spectrophotometer, is described in EPA 7473 and is validated for laboratory as well as field analysis.

摘要

Precise and rapid determination of total mercury in Powder face can be performed using Direct Mercury Analyzer. Such an instrument requires no sample wet chemistry or pretreatment. Once a weighed sample portion is introduced into the instrument, analysis is complete in six minutes. Direct analysis of mercury, using the integrated sequence of Thermal Decomposition, Catalyst Conversion, Amalgamation, and Atomic Absorption Spectrophotometer, is described in EPA 7473 and is validated for laboratory as well as field analysis.

摘要

Precise and rapid determination of total mercury in Lipstick can be performed using Direct Mercury Analyzer. Such an instrument requires no sample wet chemistry or pretreatment. Once a weighed sample portion is introduced into the instrument, analysis is complete in six minutes. Direct analysis of mercury, using the integrated sequence of Thermal Decomposition, Catalyst Conversion, Amalgamation, and Atomic Absorption Spectrophotometer, is described in EPA 7473 and is validated for laboratory as well as field analysis.

摘要

春节前，武汉查出3596.9公斤海南豇豆含禁用农药水胺硫磷，随即全部销毁。为防有毒豇豆再次流入，今年5月6日前，海南豇豆将不能出现在武汉市场。对此，海南农业厅质量处处长称，问题豇豆是由于检测设备的误差导致。而继武汉之后，合肥、杭州、广州均发现了问题豇豆。农业部已下发紧急通知，要求加强农产品生产环节的监管。 水胺硫磷(isocarbophos)为一种速效广谱杀虫杀螨剂，又称作羧胺磷，在农业害虫防治方面担当着重要的角色。但各种资料中均明文规定不可以用于蔬菜。在海南的蔬菜中发现水胺硫磷，明显是在蔬菜种植过程中滥用了此类农药，从而造成了带毒蔬菜。 实验前处理主要参照NY/T761-2004 （蔬菜和水果中有机磷、有机氯、拟除虫菊酯和氨基甲酸酯类农药多残留检测方法）及GB/T 5009.218-2008（水果和蔬菜中多种农药残留量的测定）方法，使用凝胶净化（GPC）方法除去大部分的干扰物质，将处理好的样品用HPLC进行检测。

摘要

有样品比较复杂，前处理难度大，有的样品铅、砷含量较低，取样量太少的话达不到后续分析仪器的检出限。因此需要建立准确、可高、灵敏、快速的分析方法。微波灰化是一种快速处理样品技术，比湿法消化的取样量大的5~10倍，因此大大的提高了仪器的检出限；同时样品的处理时间短、损失少，是比较准确可靠的样品前处理方法。

摘要

摘 要：2008年7月分别选取崇明典型农田土壤，对其中的9种有机磷农药残留进行检测。结果表明：水稻田土壤和蔬菜地土壤有机磷农药均有不同程度检出。水稻田土壤检测出的有机磷农药总量在0.23～0.69 μg g-1之间，检出种类主要为甲拌磷、乐果、二嗪农、马拉硫磷、对硫磷；蔬菜地土壤检出的有机磷农药总量为0.10～0.57 μg g-1，检出种类主要为氧化乐果、甲拌磷、乐果、马拉硫磷和对硫磷。其中，对硫磷的检出量和检出率均最高。不同土地利用方式对土壤有机磷农药残留有一定影响，水稻田土壤有机磷农药残留高于蔬菜地土壤，这可能与水稻田与蔬菜西瓜田耕种方式和施用农药量有关。 关 键 词：有机磷农药；农田；土壤；崇明

摘要

摘要：在上海崇明岛采集了101个耕层土壤样品,利用GC-µECD测定了8种多氯联苯(PCBs)浓度,并对其进行多元统计分析,探讨了其可能的污染来源.结果表明,样品PCBs浓度范围为ND-261ng/g,均值为56.0ng/g.低氯联苯含量和检出率均较高.不同土壤利用方式对PCBs残留量有一定影响,表现为水稻田土壤>大棚蔬菜西瓜田土壤>露天蔬菜西瓜田土壤.主成分分析和相关性研究结果表明,土壤中低氯联苯同系物间相关性较好,污染来源可能为同一类. 关键词：多氯联苯；农田；土壤；崇明岛；残留

摘要

Abstract:In this work we have developed a cost-effective method for the analysis of methy1 mercury (MeHg)in seawater fish muscle.The novelty of this method lies in the use of microwave-assissted exraction with acidia solution(HCL),addition of toluene ,and subsequent extraction with cysteine acetate solution where only MeHg is present because of its affinity for cysteine groups.MeHg in cysteine ……