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1.
新刊导读     
农 药商纯间三氟甲基苯胺开发/许丹倩等//农药.-2001,40(1).-9~12已见文献报道的合成间三氟甲基苯胺的方法可分为6种:水解法、氨化法、三氟甲基化法、脱卤还原法、氟代还原法、还原法,在对它们进行试验和分析对比的基础上.开发出以甲苯为起始原料,经催化氯化和氟化、精馏制备含量在99%以上的三氟甲苯,再通过硝化、加氢还原和精馏得到高纯间三氟甲基苯胺和副产邻三氟甲基苯胺的新工艺。  相似文献   

2.
韩经龙  刘海辉 《浙江化工》2003,34(12):5-5,9
催化剂FeCl3/I2与催化剂FeCl3/Fe催化氯化三氟甲苯合成了间氯三氟甲苯,比较了两种催化剂的活性,并研究了反应温度、转化率对间氯三氟甲苯选择性的影响。  相似文献   

3.
以对氯三氟甲苯为原料,经硝硫混酸硝化得到3,5-二硝基对氯三氟甲苯,3,5-二硝基对氯三氟甲苯在铜粉催化下经Ullmann偶联反应得到2,2’,6,6’-四硝基-4,4’-二(三氟甲基)联苯。硝化反应收率为93%;偶联反应的优化条件为:以甲苯为反应介质,m(C6H2C1CF3N204):m(Cu)=1:0.25,110℃反应1.5h,偶联反应收率达73%以上。总收率可达68%。  相似文献   

4.
研究了TiO2负载Pd-Fe催化间硝基三氟甲苯的常压加氢反应,考察了反应温度和催化剂质量浓度对加氢反应的影响,建立了加氢反应的动力学方程。结果表明:在间硝基三氟甲苯初始浓度0.125 mol/L,催化剂质量浓度0.32 g/L,氢气压力0.1 MPa,,323.2 K和2.5 h条件下,间硝基三氟甲苯转化率达到99.2%。通过拟合实验数据,加氢反应对间硝基三氟甲苯浓度表现为1级,对催化剂质量浓度表现为0.464级,反应活化能为22 728.0 J/mol。由动力学方程回算得到的间硝基三氟甲苯浓度与实验值能较好地吻合。  相似文献   

5.
间羟基三氟甲苯的合成   总被引:1,自引:0,他引:1  
蔡春  姚红  吕春绪 《江苏化工》2002,30(5):46-47
以三氟甲苯为原料,经硝化、还原、重氮化、水解等过程,可以提到重要的农药中间体间羟基三氟甲苯,产物总收率达70%以上,在较高温度下进行重氮化反应时,可以显著提高间氨基三氟甲苯重氮化、水解反应的收率。  相似文献   

6.
蔡春  吕春绪 《农药》2002,43(9):12-13
以三氟甲苯为原料,经硝化、还原、重氮化、水解等过程,可以得到重要的农药中间体间羟基三氟甲苯,产物总收率达70%以上,在较高温度下进行重氮化反应时,可以显著提高间氨基三氟甲苯重氮化、水解反应的收率。  相似文献   

7.
介绍了2.6-二氯-4-三氟甲基苯胺的合成方法,并且以3 4-二氯三氟甲苯为起始原料,二甲胺为甲胺化剂,通过二甲胺化,卤化,催化侧链甲基卤化以及水解四部反应合成了2.6-二氯-4-三氟甲基苯胺.收率90%,产品熔点34℃ ~ 35℃,纯度98%.  相似文献   

8.
本文介绍了用氯化水解法制取对氟苯甲醛的合成路线。以对氟甲苯为原料,在紫外光的作用下进行侧链氯化转化为a,a-二氯对氟甲苯,经95%乙醇催化水解得到高纯度的对氟苯甲醛,总收率达到86.23%。  相似文献   

9.
对氟苯甲醛的合成研究   总被引:2,自引:0,他引:2  
醉介绍了用氯化水解法制取对氟苯甲醛的合成路线。以对氟甲苯为原料,在紫外光的作用下进行侧链氯化转化为a,a-二氯对氟甲苯,经95%乙醇催化水解得到高纯度的对氟苯甲醛,总收率达到86.23%。  相似文献   

10.
以2,4,5-三氯三氟甲苯为原料,经氨解反应、催化加氢脱氯反应两步制得了对三氟甲基苯胺,收率70%。  相似文献   

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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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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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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   

18.
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   

19.
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   

20.
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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