离子液体催化合成食用香料乳酸乙酯的研究

以离子液体[HSO3-pmim]HSO4为催化剂,乳酸和乙醇为原料合成乳酸乙酯。通过正交实验考察了影响酯化反应的主要因素,确定最佳合成条件为:[HSO3-pmim]HSO4用量10mL,酸醇摩尔比1.0∶1.5,反应温度110℃,反应时间2.0h,酯化率达96.7%。离子液体易分离回收,可重复使用。     

酸性离子液体催化合成N-甲酰吗啉

合成了7种酸性离子液体,并将其应用于催化合成N-甲酰吗啉的反应中,筛选出了一种可以重复使用的离子液体[HSO3-pmim]HSO4,并对其进行了表征。以吗啉和甲酸为原料,离子液体[HSO3-pmim]HSO4为催化剂,以一种环保的工艺合成了N-甲酰吗啉。用红外光谱对产品结构进行了分析表征,和N-甲酰吗啉标准谱图一致,用气相色谱测定产品质量分数大于99.8%。考察了影响反应的主要因素,确定了较佳反应条件:n(甲酸)∶n(吗啉)=1.15∶1,反应温度85~95℃,反应时间8.0 h。在该条件下[HSO3-pmim]HSO4重复使用7次后,没有明显消耗,N-甲酰吗啉的收率大于81.3%。     

酸性离子液体催化合成乙酸苯乙酯

以酸性离子液体己基甲基咪唑硫酸氢盐[n-C6Im][HSO4]为催化剂催化合成乙酸苯乙酯(PEAC)。通过对影响转化率的各种因素考察,得到最佳合成条件:2-苯乙醇与乙酸乙烯酯物质的量比为1∶1.2,离子液体催化剂用量5%(质量分数),反应温度140℃,反应时间6 h,PEAC转化率为91.8%。离子液体催化剂重复使用4次后,转化率开始缓慢下降,但补充适量硫酸后离子液体即可恢复催化活性。与传统的强酸催化剂相比,[n-C6Im][HSO4]具有合成的PEAC色泽好、催化剂易回收与重复利用的优点。     

酸性离子液体催化合成季戊四醇棕榈油酸酯

合成两种酸性离子液体,正丁基甲基咪唑硫酸氢盐[n-C4Im][HSO4]和异丁基甲基咪唑硫酸氢盐[i-C4Im][HSO4],催化合成季戊四醇棕榈油酸酯(PPAE),结果发现[i-C4Im][HSO4]催化活性最大。通过对影响转化率的各种因素考察,得到最佳反应条件:棕榈油酸与季戊四醇物质的量比为6∶1,离子液体催化剂用量5%(质量分数),反应温度220℃,反应时间4 h,PPAE转化率为91.8%。离子液体催化剂重复使用2次后,转化率开始缓慢下降,但补充适量硫酸后离子液体即可恢复催化活性。与传统的强酸催化剂相比,[i-C4Im][HSO4]具有合成的PPAE色泽好、催化剂易回收与重复利用的优点。     

微波辐射下磺酸基功能化离子液体无溶剂催化合成4-甲基香豆素及其衍生物

研究了3种磺酸基功能化离子液体催化香豆素及其衍生物的合成,取代酚与乙酰乙酸乙酯在无溶剂微波辐射条件下,通过Pechmann缩合反应,合成了一系列4-甲基香豆素衍生物,探讨了反应时间、反应温度、催化剂用量、离子液体重复使用性能诸因素对产品产率的影响。结果表明,离子液体[C3SO3Hmim]HSO4是合成目标产物的良好催化剂,微波辐射时间10 min,反应温度100℃,n(酚)∶n(乙酰乙酸乙酯)=1∶1,催化剂用量x([C3SO3Hmim]HSO4)=20%时,最高产率可达94%。该法反应条件温和,操作简便,产物易分离,产率高,环境友好,离子液体可重复使用4次。     

离子液体催化氯乙酸甲酯合成氯乙酸-2-庚酯的研究

探索了离子液体催化氯乙酸甲酯和2-庚醇的酯交换反应,制备了1-甲基-3-（丙基-3-磺酸基）咪唑对甲苯磺酸盐[MIM-PS][PTSA]、1-甲基-3-（丙基-3-磺酸基）咪唑硫酸氢盐[MIM-PS][HSO₄]、1-丁基-3-甲基咪唑硫酸氢盐[BMIM]HSO₄、N-甲基咪唑磷酸盐[HMIM]H₂PO₄四种离子液体催化剂并用于酯交换反应,通过考察产品氯乙酸-2-庚酯收率,筛选出最佳催化剂[MIM-PS][PTSA]。并用[MIM-PS][PTSA]考察了反应温度、反应时间、催化剂添加量、催化剂循环使用对合成产品收率的影响。结果表明：将氯乙酸甲酯和2-庚醇在100 ℃下,添加5% [MIM-PS][PTSA]催化剂,反应6 h,合成氯乙酸-2-庚酯,收率可达76.3%,离子液体重复使用3次,氯乙酸-2-庚酯收率仍大于初次收率的95%。本实验用离子液体做溶剂或催化剂,反应条件稳定,可循环利用、对环境友好,且产品收率高,为工艺放大提供实验条件参考。     

离子液体催化合成乙酸丙酯的研究

用微波方法制备了[bmim]PTSA离子液体,应用于催化合成乙酸丙酯反应中,分析了离子液体的催化活性,研究了影响酯化反应的各种因素。结果表明：离子液体[bmim]PTSA是该酯化反应良好溶剂和催化剂,离子液体用量15mL,醇酸摩尔比1．5：1．0,反应时间2．0h,酯化率达94．2％。离子液体易分离回收,可重复使用。     

离子液体[bmim]PTSA中催化合成乙酸异戊酯的研究

以离子液体[bmim]PTSA作为酯化反应的溶剂及催化剂合成乙酸异戊酯,研究了影响反应的各种因素,结果表明,最佳反应条件为:离子液体用量15 mL,醇酸摩尔比1.5∶1.0,反应时间2.0 h,酯化率92.2%。离子液体易分离回收,可重复使用。     

酸性离子液体催化柠檬酸三丁酯的合成研究

制备了四种离子液体用于催化酯化柠檬酸三丁酯的合成。系统考察了酸与醇的配比、催化剂的种类、及催化剂重复使用性。结果表明,较佳催化剂为酸性功能化离子液体[HSO3-bPydin][HSO4],较佳反应条件是:酸与醇摩尔比为1∶5,催化剂用量为反应物总质量的15%,反应3 h,此条件下酯化率97%,反应后分离出的离子液体未经任何处理重复使用10次,酯化率仍为96%。     

一种新型离子液体在尼泊金乙酯合成中的应用

研究了新型离子液体1-(4-磺酸基)丁基-3-甲基咪唑磺酸盐[BSmim]HSO4催化合成尼泊金乙酯,考察了反应时间,反应温度,醇酸比和离子液体用量对尼泊金乙酯产率的影响,实验结果表明尼泊金乙酯的最佳反应条件为当反应时间2.5 h,反应温度为回流温度,醇酸比为2.5∶1,离子液体用量3 m L。以该离子液体作为合成尼泊金酯的催化剂具有产率高,操作简便,可重复使用,具有较好的应用前景。     

Sapindaceae,cyanolipids, and bugs

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.     

2008～2009年世界塑料工业进展

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。     

Insect antifeedant properties of anthranoids from the genusVismia

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.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

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.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

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.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

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.