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1.
酸功能化离子液体催化合成三乙酸甘油酯   总被引:1,自引:0,他引:1  
合成了[HSO3-pmim]Cl、[HSO3-pmim][BF4]、[Hpyro][HSO4]和[HSO3-pmim][PTSA]离子液体,用1H-NMR和FT-IR对离子液体的结构进行了确定。将这几种酸功能化离子液体应用于三乙酸甘油酯的合成反应中,筛选出了一种催化效果好、可重复使用的离子液体[HSO3-pmim][PTSA]。考察了催化剂用量、原料配比、反应时间和反应温度对反应结果的影响。得到了较佳反应条件:即n(甘油)︰n(乙酸)=1︰8,催化剂用量为醇酸总质量的10.5%,反应时间6 h,反应温度120℃。并对离子液体的重复使用性进行了考察,重复使用7次后,三乙酸甘油酯的收率仍大于90%。  相似文献   

2.
周立国 《山西化工》2010,30(6):5-7,11
以苯和三氯化磷为主要原料,合成苯基二氯化膦。通过正交实验优化原料配比和反应时间;确定了最佳原料配比和反应时间;通过对比优选出氯化钠为络合剂,并对其用量和粒径进行优化。结果表明,最佳反应条件为n(苯)∶n(三氯化铝)∶n(三氯化磷)∶n(氯化钠)=1.0∶1.1∶1.3∶1.6,反应时间为4 h,产率达到了91.6%。  相似文献   

3.
本文研究了离子液体1-丁基-3-甲基咪唑溴盐[Bmim]Br的合成工艺条件,研究了反应时间、反应温度、1-甲基咪唑和溴代正丁烷物质的量配料比对[Bmim]Br收率的影响。确定了反应温度对离子液体的收率影响最大,原料配比次之,反应时间影响最小,最佳合成条件为:反应温度70℃,反应时间24h,原料物质的量配比1∶1.0。  相似文献   

4.
本文研究了离子液体1-烯丙基-3-甲基咪唑氯盐([AMIM]Cl)的合成,考察了反应时间、反应温度、原料配比对[AMIM]Cl收率的影响,确定最佳反应时间为8h,最佳反应温度为80℃,原料氯丙烯与1-甲基咪唑最佳物质的量比为1∶3。另外,考察了[AMIM]Cl对木质素的溶解性能,确定80℃时木质素在离子液体[AMIM]Cl中的溶解度为最佳。  相似文献   

5.
研究了离子液体催化合成2-(4-乙基苯甲酰基)苯甲酸。并对离子液体中[Bmim]Cl与三氯化铝的摩尔比、原料配比、反应温度和反应时间等工艺条件进行了考察。较优工艺条件为:n(AlCl3)∶n([Bmim]Cl)=1∶3,n(离子液体)∶n(邻苯二甲酸酐)∶n(乙苯)=1∶1∶1,反应温度为50℃,反应时间为4h,在此条件下,[Bmim]Cl-AlCl3催化邻苯二甲酸酐的转化率可达100%,目标产物2-(4-乙基苯甲酰基)苯甲酸的选择性达97.14%,可避免使用有机溶剂。  相似文献   

6.
按文献方法合成了不同x值的Et3NHCl-xAlCl3离子液体,并将其用于催化合成苯基二氯化膦,研究了离子液体酸性、用量对反应活性的影响,对其重复使用性进行了考察,并对合成的苯基二氯化膦进行了红外表征。  相似文献   

7.
以氯化胆碱、尿素为原料合成氯化胆碱-尿素低共融体系离子液体,考察原料配比、反应温度、反应时间对离子液体合成的影响。最佳合成条件为:n(尿素)∶n(氯化胆碱)=2∶1,反应温度为80℃,反应时间为90 min。利用傅里叶变换红外光谱仪、紫外可见分光光度计、旋转黏度计以及溶血实验对合成产物进行检测。合成产物的红外光谱图与氯化胆碱-尿素离子液体谱图一致;由紫外可见分光光度计检测可知,氯化胆碱-尿素低共融体系合成过程中透过率随时间的延长而增大,最终趋于稳定;合成的离子液体的黏度随温度的升高而减小;溶血实验结果表明,合成的离子液体不会发生溶血现象,具有良好的生物相容性。利用合成的离子液体溶解牛皮胶原,通过分析溶解产物的红外光谱可知,离子液体能够直接对牛皮中胶原进行物理溶解。  相似文献   

8.
离子液体Et_3NHCl-xAlCl_3催化合成苯基二氯化膦研究   总被引:1,自引:0,他引:1  
按文献方法合成了不同x值的Et3NHCl-xAlCl3离子液体,并将其用于催化合成苯基二氯化膦,研究了离子液体酸性、用量对反应活性的影响,对其重复使用性进行了考察,并对合成的苯基二氯化膦进行了红外表征.  相似文献   

9.
采用AlCl3和[Bmim]Cl不同摩尔比的[Bmim]C1-xA1C13离子液体为催化剂,研究了不同条件下1-十二烯与苯的烷基化反应。实验结果表明,以A1Cl3和[Bmim]Cl的摩尔比为2.0([Bmim]Cl-2A1C13)的离子液体为催化剂,在反应温度25℃、反应时间30 min,苯、烯及离子液体的摩尔比为5︰1︰0.03的条件下,正十二烯的转化率可达98.32%,2-LAB的选择性可达36.76%。离子液体和产物可形成易于分离的双液相,简化了催化剂与产物的分离操作。  相似文献   

10.
氯铝酸离子液体催化合成香豆素结构荧光染料   总被引:2,自引:0,他引:2  
以[BMIm]Br-AlCl3离子液体为催化剂,通过4-二乙氨基水杨醛、氰乙酸乙酯和邻氨基苯酚一锅煮反应合成了典型的香豆素结构荧光染料3-(2′-苯并口恶唑基)-7-二乙基氨基-2H-1-苯并吡喃-2-酮。考察了离子液体的催化活性,较系统地研究了催化剂路易斯酸性、催化剂用量、反应温度、反应时间对产率的影响。最佳反应条件为:n(4-二乙氨基水杨醛)∶n(氰乙酸乙酯)∶n(邻氨基苯酚)∶n(离子液体〔n(AlCl3)/n([BMIm]Br-AlCl3)=0.67〕)=1∶1∶1∶1,反应温度100~110℃,反应时间60 min,产物最终实测收率达78.3%。  相似文献   

11.
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   

13.
14.
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   

15.
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   

16.
17.
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   

18.
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   

19.
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   

20.
建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。  相似文献   

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