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1.
论文从不同的原料(邻硝基甲苯、邻硝基甲苯醇、邻硝基苯甲酸、邻硝基苯甲酰胺、邻硝基苯甲酰氯、苯甲醛、邻硝基苄氯、邻硝基乙苯)出发,对邻硝基苯甲醛的化学合成进行了综述,同时对电化学合成也作了简要介绍。  相似文献   

2.
邻氟苯甲腈的合成研究   总被引:6,自引:0,他引:6  
以邻甲苯胺为原料 ,采用四步反应法合成邻氟苯甲腈。 (1)邻甲苯胺经西曼反应合成邻氟甲苯 ,收率 6 5 % ;(2 )邻氟甲苯经氯化、水解得到邻氟苯甲醛 ,以过氧化苯甲酰为氯化引发剂 ,氧化锌为水解催化剂 ,收率 80 % ;(3)邻氟苯甲醛经肟化反应得到邻氟苯甲醛肟 ,收率 87% ;(4)肟用乙酸酐脱水合成出邻氟苯甲腈 ,收率 76 % ,产品质量分数大于 99%。  相似文献   

3.
在乙醇钠催化下使邻硝基甲苯与草酸二乙酯缩合,然后经水解、双氧水氧化和盐酸酸化得到邻硝基苯乙酸,收率62%。在20%NaOH水溶液中,FeO(OH)催化水合肼还原邻硝基苯乙酸得到邻氨基苯乙酸,经重氮化和卤置换反应得到邻卤苯乙酸,收率65%~73%。总收率为40%~45%。  相似文献   

4.
邻硝基甲苯与草酸二乙酯经缩合、氧化连续反应,合成邻硝基苯乙烯,此方法使操作简化,并提高了收率。用原乙酸三乙酯在对甲苯磺酸的催化下,对邻硝基苯乙烯进行酯化,得以高收率的邻硝基苯乙酸乙酯。  相似文献   

5.
邻甲酚醛树脂制备工艺稳定,加工简单,但随着对邻甲酚醛树脂研究的越发深入,更高性能的高邻位邻甲酚醛树脂被开发应用,其优点为制品成型快固化速度快。但现阶段对其的研究较少且不全面。研究了采用醋酸锌与草酸组合的双催化剂制备高邻位邻甲酚醛树脂的方法,对反应过程中醛酚比、催化剂的用量、反应时间、反应温度等条件进行响应面分析,得到最优的高邻位邻甲酚醛树脂制备条件,并用红外及核磁仪器表征了树脂结构,测定了树脂的软化点与邻位率。最终成功制备了软化点85℃、邻位率87%的高邻位邻甲酚醛树脂。  相似文献   

6.
黄家锐  郭成  曹飞 《化工时刊》2003,17(1):37-39
研究了以邻硝基乙苯为原料,经催化加氢还原成邻乙基苯胺的过程:考察了不同催化剂,催化剂的用量,反应温度、氢气压,搅拌速度等对邻硝基乙苯加氢反应速度的影响。结果表明,采用催化剂Raney Ni,最佳的加氢工艺条件为:反应温度140℃、氢压3.0MPa、搅拌转速1300r/min、催化剂用量为1%,邻硝基乙苯加氢的转化率>99.5%,产物邻乙基苯胺的纯度>99.5%。  相似文献   

7.
袁华  刘培杰 《湖北化工》1997,14(4):13-13,17
以低压汞灯为引发光源,对邻硝基甲苯侧链氯化合成了邻硝基氯苄。经二次氯化,邻硝基甲苯的转化率可达50%。  相似文献   

8.
刘炳文  盖宏伟  李长银 《辽宁化工》2014,(11):1385-1386,1395
以邻溴苯胺为原料通过重氮化,碘代反应合成了邻溴碘苯,收率83%(HPLC纯度99.5%);然后再与异丙基溴化镁反应生成邻溴苯基溴化镁,再与硼酸三甲酯进行亲核取代、水解生成邻溴苯硼酸,收率59.3%(HPLC纯度99.6%)。  相似文献   

9.
以邻氯硝基苯和氟化钾为原料合成了邻氟硝基苯,并进行还原和酰化,制备了一系列的N-邻氟苯基酰胺。  相似文献   

10.
本文研究了以化学氧化剂氧化、酸性条件下铁粉还原处理邻硝基乙苯,从而得到邻氨基苯甲酸的方法。研究结果表明直接氧化-还原的方法处理邻硝基乙苯具有一定的可行性。  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   

13.
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   

14.
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   

19.
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   

20.
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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