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1.
建立了茶叶中唑虫酰胺残留量快速测定的气相色谱-质谱法。茶叶中的唑虫酰胺用正己烷-丙酮(7:3, V/V)混合液提取,经石墨化碳黑固相萃取小柱净化,用正己烷-丙酮(9:1, V/V)混合液洗脱,浓缩定容后,用气相色谱-质谱法测定,外标法定量。结果表明,目标物质在0.010~0.500 mg/L范围内的线性关系良好;空白样品在0.010~0.500 mg/L范围三水平加标回收实验中的平均回收率在75.2%~112.8%之间,相对标准偏差( n=3)为2.85%~5.12%;方法的定量下限为0.005 mg/kg。该方法操作简单、检测灵敏度高,能满足茶叶中唑虫酰胺残留量的检测需求。  相似文献   

2.
气相色谱法快速测定叶类蔬菜中拟除虫菊酯类农药残留   总被引:1,自引:0,他引:1  
建立了快速测定叶类蔬菜中拟除虫菊酯残留量的气相色谱方法。叶类蔬菜中的拟除虫菊酯经丙酮-石油醚混合液超声波辅助提取,经中性氧化铝-石墨化碳柱净化,正己烷定容,用外标法定量,以气相色谱法(GC-μECD)测定。试验结果表明:样品以0.20、0.10、0.05 mg/kg水平添加时,联苯菊酯、三氟氯氰菊酯、顺式氰戊菊酯和溴氰菊酯回收率分别为78.5%~104.3%,80.5%~106.5%,85.3%~107%,84.5%~108.5%,最低检出限为0.001 mg/L,相对标准偏差小于5%。  相似文献   

3.
庞艳华  刘淑艳  李叶  那晗 《广州化工》2011,39(7):115-116,149
建立了一种测定食用菌中八氯二丙醚(S-2)残留量的气相色谱方法.样品中的八氯二丙醚经丙酮-正己烷混合溶剂提取,浓硫酸液-液分配磺化法进行净化,以气相色谱法(GC-ECD)测定,外标法定量.实验结果表明:样品中加入0.005~0.05mg/kg浓度水平的S-2,回收率在72.4%~104.4%之间,相对标准偏差小于7.8...  相似文献   

4.
郭明程  郑尊涛  聂东兴  汤涛 《农药》2020,59(2):132-134
[目的]建立超高效液相色谱-串联质谱法测定杨梅中噻嗪酮残留量的方法。[方法]杨梅样品经乙腈提取,弗罗里硅土柱净化,超高效液相色谱-串联质谱检测。[结果]噻嗪酮在0.5~500μg/L范围内线性关系良好,相关系数为0.9952,在0.01~2.0 mg/kg添加水平下,噻嗪酮在杨梅中的平均回收率为88%~92%,相对标准偏差为2.43%~3.88%,噻嗪酮在杨梅中的定量下限为0.01 mg/kg。[结论]该方法简便、快速、准确、灵敏度高,可用于杨梅中噻嗪酮的残留检测。  相似文献   

5.
[目的]建立毒杀芬在农田土壤中残留量的气相色谱检测方法。[方法]样品采用正己烷提取后,经PSA和Carb净化,气相色谱电子捕获检测器测定,外标法定量。[结果]方法定量限(S/N=10∶1)为0.01 mg/kg,在0.10~3.0 mg/L的质量浓度范围内,相关系数为0.998,在土壤中添加0.01~0.1 mg/kg范围内(n=6),回收率为75%~92%,相对标准偏差(RSD)为4.1%~5.4%。[结论]该方法适用于土壤中毒杀芬的快速检测。  相似文献   

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气相色谱法测定黄瓜中哒螨灵残留量   总被引:1,自引:0,他引:1  
建立了一种操作简单、快速测定哒螨灵在黄瓜中残留量的气相色谱分析法.黄瓜制备样品经提取、净化后用带有ECD检测器的气相色谱仪检测哒螨灵的残留量,仪器的最小检出量为1.0×10-11g,方法最低检出质量分数为0.01 mg/kg,样本添加回收率在81.6%~107.4%之间,精密度试验结果表明变异系数为2.4%~5.5%.  相似文献   

7.
腈菌唑在大葱中的残留分析与消解动态   总被引:1,自引:0,他引:1  
[目的]腈菌唑被认为是防治大葱锈病等病害应用前景较好的杀菌剂,但尚未见腈菌唑在大葱中残留检测方法和残留消解动态的研究报道,建立腈菌唑在大葱中残留检测方法和残留消解动态的方法.[方法]采用气相色谱质谱法(GC-MS)测定了腈菌唑在春季大葱中的残留消解动态和最终残留量.样品经乙腈提取,SAX/PSA固相萃取柱净化,气相色谱质谱选择离子(GC/MS/SIM)检测.[结果]建立的大葱中腈菌唑残留量检测方法在0.01~0.10 mg/kg水平的平均添加回收率为93.0%~107.9%,相对标准偏差为2.1%~5.6%,腈菌唑检测限为0.002 mg/kg.腈菌唑在大葱中消解较快,半衰期为3.4 d.12.5%腈菌唑乳油按推荐剂量(62.5 mg a.i./kg)和加倍剂量(125.0 mg a.i./kg)对水喷雾2-3次,末次施药后7、14 d腈菌唑在大葱中残留量为0.003~0.017 mg/kg.[结论]建立的大葱中腈菌唑残留检测方法准确可靠.大葱收获时最终残留量低于日本规定的最大允许残留量(MRL),满足出口国要求.  相似文献   

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建立固相萃取-气相色谱-质谱法测定茶叶中蒽醌残留的方法。茶叶经0.1%乙酸乙腈(V/V)提取,盐析后旋转蒸发至近干,正己烷溶解,弗罗里硅土柱净化,丙酮-正己烷(2︰8,V/V)洗脱,丙酮定容,气相色谱-质谱(GC-MS)检测。采用HP-5MS色谱柱(30 m×0.25 mm×0.25μm)结合程序升温对样品进行分离,选择SIM反应监测模式,外标法定量。蒽醌在10.0~1000.0μg/L范围内具有良好的线性关系,相关系数为0.9998。茶叶样品在0.01,0.02和0.10 mg/kg 3个添加水平,回收率范围为90.2%~95.0%,相对标准偏差为3.0%~5.5%,检出限为0.002 mg/kg,定量限为0.008 mg/kg。该方法准确、灵敏、快速,可满足茶叶中蒽醌残留的确证检测。  相似文献   

9.
固相萃取气相色谱法检测烟叶中拟除虫菊酯类杀虫剂残留   总被引:2,自引:0,他引:2  
宋春满  逄涛  师君丽  孔光辉  晋艳 《农药》2012,51(1):51-52
[目的]建立烟叶中拟除虫菊酯类杀虫剂多残留的固相萃取-气相色谱检测方法.[方法]烟叶样品经正己烷-乙酸乙酯超声提取、Florisil固相萃取柱净化后,用气相色谱电子捕获检测器检测.[结果]7种拟除虫菊酯类杀虫剂在0.1、0.5、1.0 mg/kg三个加标水平上的回收率为85.32%~101.21%,相对标准偏差为2.97%~4.88%,检出限为0.003~0.005 mg/kg.[结论]该方法灵敏准确,适用于烟叶中拟除虫菊酯类杀虫剂多残留分析.  相似文献   

10.
[目的]利用气相色谱-质谱仪及固相萃取前处理技术建立了虫螨腈在马铃薯中的残留量测定方法.[方法]样品通过乙腈水混合液提取,固相萃取柱净化,气相色谱-质谱仪检测.[结果]虫螨腈在马铃薯中的添加水平为0.01、0.05、0.5 mg/kg,平均回收率为80.3%~93.2%,相对标准偏差为2.2%~6.0%,虫螨腈在0.0...  相似文献   

11.
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

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收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

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收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

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Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.  相似文献   

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Ethanol and α-pinene were tested as attractants for large wood-boring pine beetles in Alabama, Florida, Georgia, North Carolina, and South Carolina in 2002–2004. Multiple-funnel traps baited with (−)-α-pinene (released at about 2 g/d at 25–28°C) were attractive to the following Cerambycidae: Acanthocinus nodosus, A. obsoletus, Arhopalus rusticus nubilus, Asemum striatum, Monochamus titillator, Prionus pocularis, Xylotrechus integer, and X. sagittatus sagittatus. Buprestis lineata (Buprestidae), Alaus myops (Elateridae), and Hylobius pales and Pachylobius picivorus (Curculionidae) were also attracted to traps baited with (−)-α-pinene. In many locations, ethanol synergized attraction of the cerambycids Acanthocinus nodosus, A. obsoletus, Arhopalus r. nubilus, Monochamus titillator, and Xylotrechus s. sagittatus (but not Asemum striatum, Prionus pocularis, or Xylotrechus integer) to traps baited with (−)-α-pinene. Similarly, attraction of Alaus myops, Hylobius pales, and Pachylobius picivorus (but not Buprestis lineata) to traps baited with (−)-α-pinene was synergized by ethanol. These results provide support for the use of traps baited with ethanol and (−)-α-pinene to detect and monitor common large wood-boring beetles from the southeastern region of the USA at ports-of-entry in other countries, as well as forested areas in the USA.  相似文献   

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