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1.
用聚乙二醇1000作相转移催化剂,在常压下由苯胺和溴乙烷合成了N,N-二乙基苯胺。研究了多种反应因素对目的产物产率的影响,提出了常压催化合成目的产物的最佳工艺条件是:苯胺和溴乙烷的摩尔比为1:1.50,催化剂用量0.20g,在30ml、35%的氢氧化钠溶液中,反应温度65℃,常压反应5h,产品收率69.72%。  相似文献   

2.
田庆伟 《当代化工》2005,34(2):109-111
用聚乙二醇800作相转移催化剂,在常压下由苯胺和溴乙烷合成了N,N-二乙基苯胺,研究了多种反应因素对目的产物产率的影响,提出了常压催化合成目的产物的最佳工艺条件是:n(苯胺):n(溴乙烷)=1:1.50,催化剂用量0.40g,在40mL质量分数为50%的氢氧化钠溶液中,反应温度65℃,常压反应7h,产品收率71.5%。  相似文献   

3.
用聚乙二醇600作相转移催化剂,在常压下由苯胺和溴乙烷合成了N,N 二乙基苯胺,研究了多种反应因素对目的产物产率的影响,提出了常压催化合成目的产物的优化工艺条件是:苯胺和溴乙烷的物质的量比为1∶1 75,催化剂用量1 00g,在30mL35%的氢氧化钠溶液中,反应温度65℃,常压反应6h,产品收率75 74%。  相似文献   

4.
用四甲基氢氧化铵作相转移催化剂,可在常压下由苯胺和溴乙烷合成N,N-二乙基苯胺。研究了多种反应因素对目的产物产率的影响,各影响因素对产率提高的重要性次序依次是:反应物摩尔比>氢氧化钠溶液用量>反应时间>催化剂用量>氢氧化钠溶液质量分数>反应温度。提出了常压下催化合成目的产物的最佳工艺条件是:n(苯胺)∶n(溴乙烷)=1∶2.50,催化剂用量0.40 mL,在45 mL 质量分数为0.50的氢氧化钠溶液中,反应温度65℃,常压反应7 h,产品产率90.6%。  相似文献   

5.
田庆伟 《工业催化》2010,18(5):53-58
用聚乙二醇1540作相转移催化剂,常压下由苯胺和溴乙烷合成N,N-二乙基苯胺,研究多种反应因素对目的产物收率的影响,提出了常压催化合成目的产物的最佳工艺条件:苯胺和溴乙烷物质的量比为1:1.50,催化剂用量0.60g,在25mL质量分数50%的氢氧化钠溶液中,反应温度45℃,常压反应5h,产品收率85.1%。  相似文献   

6.
聚乙二醇400相转移催化合成N,N-二乙基苯胺的研究   总被引:1,自引:0,他引:1  
田庆伟 《化学世界》2004,45(12):654-656
用聚乙二醇400作相转移催化剂,在常压下由苯胺和溴乙烷合成N,N-二乙基苯胺,研究了多种反应因素对目的产物产率的影响,提出了常压催化合成目的产物的最佳工艺条件是:苯胺和溴乙烷的摩尔比为1∶2.25,催化剂用量0.20g,在45ml35%(质量分数)的氢氧化钠溶液中,反应温度65°C,常压反应6h,产品收率79.8%。  相似文献   

7.
使用苄基三甲基氯化铵作相转移催化剂可在常压下由苯胺和溴乙烷合成N,N-二乙基苯胺。研究了多种反应因素对目的产物产率的影响,提出了常压下催化合成目的产物的最佳工艺条件。  相似文献   

8.
用正癸基三乙基溴化铵作为相转移催化剂,在常压下由苯胺和溴乙烷合成N,N-二乙基苯胺,研究了多种因素对目的产物产率的影响,提出了常压催化合成目的的产物的最佳工艺条件是:n(苯胺):n(溴乙烷)=1:1.75,相转移催化剂用量1%(摩尔分数),在35%的氢氧化钠溶液中,反应温度85℃,常压反应5 h,产品产率82.4%.  相似文献   

9.
四丁基氯化铵相转移催化合成N,N-二乙基苯胺的研究   总被引:1,自引:0,他引:1  
田庆伟 《当代化工》2002,31(4):201-203
以四丁基氯化铵作相转移催化剂 ,可在常压下由苯胺和溴乙烷合成N ,N -二乙基苯胺。研究了多种反应因素对目的产物收率的影响 ,提出了常压下催化合成目的产物的最佳工艺条件。  相似文献   

10.
相转移催化合成N,N-二乙基苯胺的研究   总被引:1,自引:0,他引:1  
用四乙基氯化胺作相转移催化剂可在常压下由苯胺和溴乙烷合成N,N-二乙基苯胺。研究了多种反应因素对目的产物产率的影响,提出了常压下催化合成目的产物的最佳工艺条件。  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   

12.
It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.  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   

18.
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   

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.
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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