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1.
用环境友好催化剂合成丙酸异戊酯的研究   总被引:2,自引:0,他引:2  
以固载杂多酸盐TiSiW12O40/TiO2为环境友好催化剂,对以丙酸和异戊醇为原料合成丙酸异戊酯的反应条件进行了研究。实验表明:TiSiW12O40/TiO2是合成丙酸异戊酯的良好催化剂,最佳反应条件为:n(醇):n(酸)=1.3:1,催化剂用量为反应物料总质量的2.0%,反应时间1.0h,反应温度95—110℃。上述条件下,丙酸异戊酯的收率可达76.2%。  相似文献   

2.
用环境友好催化剂合成肉桂酸异戊酯的研究   总被引:7,自引:0,他引:7  
本文报道了以固载杂多酸盐TiSiW12 O40 /TiO2 为环境友好催化剂 ,对以肉桂酸和异戊醇为原料合成肉桂酸异戊酯的反应条件进行了研究。实验表明 :TiSiW12 O40 /TiO2 是合成肉桂酸异戊酯的良好催化剂 ,最佳反应条件为 :n(醇 )∶n(酸 ) =4∶1,催化剂用量为反应物料总质量的 2 .0 % ,反应时间 1.5h ,反应温度 10 6 - 114℃。上述条件下 ,肉桂酸异戊酯的收率可达 70 .6 %。  相似文献   

3.
TiSiW12O40/TiO2催化合成乙酸异戊酯的研究   总被引:48,自引:3,他引:45  
杨水金  肖继  梁永光 《化学试剂》2002,24(2):107-108,121
以固载杂多酸盐TiSiW12O40/TiO2为多相催化剂,通过乙酸和异戊酯反应合成了乙酸异戊酯,并探讨了诸因素对产主的影响,结果表明,TiSiW12O40/TiO2具有良好的催化活性,醇酸摩尔比为1.2:1,催化剂用量为反应物料总量的1.0%,反应时间1.5h,反应温度11-122℃,产率可达96.3%。  相似文献   

4.
TiSiW12O40/TiO2催化合成苯甲酸戊酯   总被引:7,自引:4,他引:3  
首次报道了以固载杂多酸盐TiSiW12O40/TiO2为多相催化剂,对以苯甲酸和正戊醇为原料合成苯甲酸戊酯的反应条件进行了研究,实验表明:TiSiW12O40/TiO2是合成苯甲酸戊酯的良好催化剂,最佳反应投机倒把为:醇酸摩尔比为4:1,催化剂用量为反应物料总量的1.5%,反应时间为2.5h。上述条件下,苯甲酸戊酸的产率可达96.7%。  相似文献   

5.
TiSiW12O40/TiO2催化合成苯甲酸异戊酯   总被引:1,自引:0,他引:1  
首次报道了以固载杂多酸盐TiSiW12O40/TiO2为多相催化剂,对以苯甲酸和异戊醇为原料合成苯甲酸异戊酯的反应条件进行了研究。实验表明:TiSiW12O40/TiO2是合成苯甲酸异戊酯的良好催化剂,最佳反应条件为:醇酸摩尔比为4:1,催化剂用量为反应物料总量的2.5%,反应时间2.5h。上述条件下,苯甲酸异戊酯的产率可达83.3% 。  相似文献   

6.
王高芳 《广州化工》2006,34(5):42-43
以正丙酸和异戊醇为原料,固体杂多酸盐TiSiW12O40/TiO2为催化剂催化合成了丙酸异戊酯。探讨了醇酸物质的量比、催化剂用量、反应时间对丙酸异戊酯产品收率的影响。实验结果表明:固体杂多酸盐TiSiW12O40/TiO2对丙酸异戊酯的合成具有良好的催化活性。在醇酸物质的量比为3.0 1,催化剂用量为反应物料总质量的2.5%、反应时2.0 h,产品收率可达91.8%。  相似文献   

7.
TiSiW12O40/TiO2催化合成氯乙酸正戊酯   总被引:7,自引:5,他引:2  
首次以固载杂多酸盐TiSiW12O40/TiO2为多相催化剂,通过氯乙酸和正戊醇反应,合成了氯乙酸正戊酯,并探讨了诸因素对产率的影响,实验表明,TiSiW12O40/TiO2具有良好的催化活性,当醇酸物质的量比为1.3:1,催化剂用量为反应物料总量的1.5%,反应时间1.0h,反应温度108℃-126℃时,氯乙酸正戊酯的产率可达78.04%。  相似文献   

8.
合成肉桂酸正丁酯的催化剂研究   总被引:2,自引:0,他引:2  
杨水金  蔡逢春 《甘肃化工》2002,16(4):14-15,18
综述了离子交换树脂,TiSiW12O40/TiO2,硫酸铁铵,杂多酸,氯化铁,聚氯乙烯三氯化铁等几种不同催化剂催化合成肉桂酸正丁酯的实验结果。实验表明:离子交换树脂,TiSiW12O40/TiO2,杂多酸3种催化剂对肉桂酸正丁酯的合成反应具有良好的催化活性,具有实际应用价值。  相似文献   

9.
综述了对甲苯磺酸,TiSiW12O40/TiO2,硫酸铁铵,微波技术(对甲苯磺酸作催化剂),固体超强酸SO4^2-/TiO2,聚氯乙烯三氯化铁,钨硅酸等几种不同催化剂催化合成了肉桂酸异戊酯的实验结果。结果表明:对甲苯磺酸,固体超强酸SO4^2-/TiO2和钨硅酸3种催化剂对合成肉桂酸异戊酯的酯收率较高,具有实际应用价值。  相似文献   

10.
合成肉桂酸正戊酯的催化剂研究   总被引:3,自引:0,他引:3  
综述了浓H2 SO4、钨锗杂多酸、TiSiW12 O40 /TiO2 、离子交换树脂、磷钨杂多酸、聚氯乙烯三氯化铁等几种不同催化剂催化合成肉桂酸正戊酯的实验结果。结果表明 ,TiSiW12 O40 /TiO2 、离子交换树脂和磷钨杂多酸三种催化剂对合成肉桂酸正戊酯的酯收率较高 ,具有实际应用价值  相似文献   

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Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.  相似文献   

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2008~2009年世界塑料工业进展   总被引:4,自引:1,他引:3  
收集了2008年7月~2009年6月世界塑料工业的相关资料,介绍了2008~2009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、环氧树脂、不饱和聚酯树脂)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   

15.
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   

16.
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   

17.
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.
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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