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GC-MS测定番茄及土壤中二甲基二硫醚残留含量的分析方法 总被引:1,自引:0,他引:1
《农药》2017,(3)
[目的]建立GC-MS测定二甲基二硫醚在番茄果实及土壤中的残留量分析方法。[方法]样品经甲醇提取,用正己烷液液分配净化后采用气相色谱-质谱联用仪(GC-MS)进行测定。[结果]二甲基二硫醚标准曲线的线性范围为0.002~1mg/L,相关系数为0.9999。二甲基二硫醚在番茄中的平均回收率为76.4%~82.1%相对标准偏差为3.1%~8.9%;在土壤中的平均回收率为71.5%~84.0%,相对标准偏差为1.5%~5.7%。方法的检出限(LOD)为1.5×10~(-3)ng,定量限(LOQ)为5.0×10~(-3)ng,符合农药残留分析要求。[结论]建立了一个简便、快捷、准确的二甲基二硫醚农药残留分析方法。 相似文献
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以二甲基硫醚和双氧水为原料、钛硅分子筛为催化剂制备了二甲基砜,确定了最佳工艺条件,即常温下钛硅分子筛为二甲基硫醚质量的7%,二甲基硫醚与双氧水的摩尔比1∶1.05,反应时间1.5 h,二甲基硫醚转化率达99%以上,二甲基砜收率达98%以上。 相似文献
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用同时蒸馏萃取装置提取挥发油并用气相色谱-质谱联用仪对滇韭挥发性成分进行了分离和鉴定,分离并鉴定出95个组分,占峰面积的71 50%,用面积归一化法测定了各种成分的质量分数,其主要挥发性成分为:w(三甲基磷化硫醚) =0 15%,w(丁基丙烯基硫醚) =0 03%,w(1, 2 二乙硫基乙烯) =0 38%,w(烯丙基甲基硫醚) =0 79%,w(二烯丙基硫醚) =0 11%,w(2 甲氧基茴香硫醚) =0 15%,w(甲基乙基二硫醚) =0 02%,w(二甲基二硫醚) =0 08%,w(二烯丙基二硫醚) =0 10%,w(二丙基二硫醚) =1 03%,w〔(甲硫基)二甲基二硫醚〕=0 17%,w(甲基1 丙烯基二硫醚) =0 32%,w(二2 羟基乙基二硫醚) =0 11%,w(二甲基三硫醚) =0 02%,w(甲基2 丙烯基三硫醚) =0 06%,w(二2 丙烯基三硫醚) =0 45%,w(二丙基三硫醚) =1 54%,w(二甲基四硫醚) =0 39%,w(4H 噻唑) =0 02%,w(4, 5 二甲基噻唑) =0 50%,w(4, 5 二甲基异噻唑) =0 06%,w(5 甲氧基噻唑) =0 24%,w(3, 4 二甲基异噻唑) =0 22%,w(3, 4 二甲基噻吩) =0 27%,w(4H 2 乙基噻吩) =0 02%,w(1, 3 二噻烷) =0 03%,w(1, 3, 5 三噻烷) =0 03%,w(1, 2 二硫戊环) =0 09%,w〔2, 4 二硫杂戊烷〕=0 98%,w(3, 5 二乙基1, 2, 4 三硫戊环) =0 55%,w(二甲基亚砜) =0 05%,w(3 甲硫基丁醛) =0 02%,w(2 甲基硫代乙酸) =0 37%,w 相似文献
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《化工进展》2017,(6)
采用离子交换法制备了CoY、CuY、NiY分子筛,并在固定床吸附器上考察了工艺条件及原料烯烃含量对改性分子筛吸附脱除二甲基二硫醚性能的影响。采用密度泛函理论计算二甲基二硫醚及异丁烯在CoY、CuY、NiY分子筛上的竞争吸附行为。最后考察了高温水蒸气对吸附剂的再生效果。结果表明,CoY、CuY和NiY分子筛对二甲基二硫醚的动态饱和吸附硫容分别为47.5mg/g、36.3mg/g和40.2mg/g;其中CoY和NiY分子筛硫容量受烯烃含量的影响较大,CuY分子筛受影响较小。计算结果表明,吸附过程中S—S键的Mayer键级变化不大,烯烃中C=C键双键性质减弱。二甲基二硫醚在CoY、CuY和NiY分子筛上的吸附能分别为–59.5k J/mol、–22.2k J/mol和–30.4k J/mol,与实验数据吻合。吸附饱和后的分子筛经160℃水蒸气脱附60min后能够有效再生,且多次再生后吸附剂硫容仍保持在新鲜吸附剂的97%以上。 相似文献
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二甲基二硫醚作为MTBE中的主要硫化物之一,其不但含量高而且很难去除,成为一些MTBE生产厂家的难题。文中研究合成了嫁接硅胶的金属酞菁功能化聚合离子液体。对研究合成的6种金属酞菁功能化聚合离子液体,考察了其对二甲基二硫醚的吸附性能。并详细考察了金属酞菁单体、载体、单体用量和吸附剂用量等影响因素对吸附效果的影响。结果表明硅胶负载金属酞菁铁功能化的聚合离子液体吸附剂吸附效果最佳。最优工艺条件为:金属酞菁用量为载体的25%,吸附剂用量为150 g/L,吸附时间为15 min,吸附去除率高达83.6%。吸附剂重复使用5次后,吸附去除率仍能达到80%以上。 相似文献
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M. S. J. Simmonds W. M. Blaney F. Delle Monache M. Marquina Mac-Quhae G. B. Marini Bettolo 《Journal of chemical ecology》1985,11(12):1593-1599
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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Cheng-Le Zhao Shane Porzio Alan Smith Haiyan Ge H. T. Davis L. E. Scriven 《Journal of Coatings Technology and Research》2006,3(2):109-115
Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively.
There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized.
High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without
the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of
fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to
achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic
SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve
F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender
particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing,
and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing
or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually
preserves suspension stability during freezing.
Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago,
IL. Tied for first place in The John A. Gordon Best Paper Competition. 相似文献
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Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US
In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae
and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted
in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures
(release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species
(Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species
to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were
exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of
separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles
from the southeastern region of the US. 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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中蓝晨光化工研究院有限公司《塑料工业》编辑部 《塑料工业》2009,37(3)
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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中蓝晨光化工研究院《塑料工业》编辑部 《塑料工业》2007,35(3):1-25,67
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