合成丁酸丁酯的催化剂

综述了几种常见无机盐、固体超强酸ZrO_2/SO_4~(2-)和Fe_2O_3/SO_4~(2-)、超强酸树脂Dool-AlCl_3、磷钨杂多酸、钨锗杂多酸、TiSiW_(12)O_(40)/TiO_2等几种不同的催化剂催化合成丁酸丁酯,以及用丁醇电解直接合成丁酸丁酯的实验结果。结果表明,SnCl_2·2H_2O,Dool-AlCl_3,HPA和TiSiW_(12)O_(40)/TiO_2 4种催化剂对合成丁酸丁酯的酯收率较高,具有实际应用价值。     

TiSiW12O40／TiO2催化合成丁酸正丁酯

首次以固载杂多酸盐TiSiW12 O4 0 /TiO2 为多相催化剂 ,通过正丁酸和正丁醇反应合成了丁酸正丁酯 ,并探讨了诸因素对酯化率的影响。实验表明 :TiSiW12 O4 0 /TiO2 具有良好的催化活性 ,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 12 2～12 8℃ ,酯化率可达 98 6 %。     

合成肉桂酸正丙酯的催化剂研究进展

综述硫酸铁铵,杂多酸,氯化铁,TiSiW_(12)O_(40)/Ti_2,阳离子大孔交换树脂,SnCl_4·5H_2O,聚氯乙烯三氯化铁等几种不同催化剂催化合成了肉桂酸正丙酯的实验结果。结果表明:大孔阳离子交换树脂、杂多酸HPA和SnCl_4·5H_2O对肉桂酸正丙酯的合成反应具有良好的催化活性,具有实际应用价值。     

SnCl_4·5H_2O/C催化合成己酸异戊酯的研究

以SnCl_4·5H_2O/C为催化剂,以环己烷为带水剂,研究了催化合成己酸异戊酯的最适宜条件。实验结果表明,SnCl_4·5H_2O/C是合成己酸异戊酯的良好催化剂,最优反应条件为：己酸的量为0.08mol时,催化剂负载量为15%,催化剂用量为反应物总量的3.0%,n（己酸）：n（异戊醇）=1：1.4,反应温度120℃,反应时间120min,酯化率可达93.1%。     

TiSiW_(12)O_(40)/TiO_2催化合成丁酸异戊酯

以固载杂多酸盐TiSiW12 O4 0 /TiO2 为多相催化剂 ,通过正丁酸和异戊醇反应合成了丁酸异戊酯 ,并探讨了诸因素对酯化率的影响。实验表明 :TiSiW12 O4 0 /TiO2 具有良好的催化活性 ,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 12 0℃～ 130℃ ,酯化率可达 95 7%     

氯化铁催化合成环己酯

氯化铁(FeCl_3·6H_2O)能够代替硫酸用作酯化反应的催化剂。本文探讨了用FeCl_3·6H_2O催化合成乙酸环己酯的条件,并合成了甲酸环己酯、乙酸环己酯、丙酸环已酯和丁酸环己酯。     

甲烷磺酸铜催化酯化反应性能的研究

合成了甲烷磺酸铜,用热重和红外对其进行表征。并以甲烷磺酸铜为催化剂,研究其催化乙酸与正丁醇酯化反应中各种因素对酯化率的影响。反应条件为:醇酸物质的量比1.1∶1,催化剂用量0.5%以酸的物质质量计,反应时间2.5h,反应温度80～85℃,环己烷2.5ml为带水剂,酯化率可达97.7%。其催化活性远远高于CuSO4·5H2O、CuCl2·2H2O、CaNO32·3H2O、CuCH3COO2·H2O及其它Lewis酸催化剂。用甲烷磺酸铜作催化剂合成其它乙酸酯和氯乙酸异丙酯,酯化率高,反应后经过简单的相分离就可重复使用,并且重复使用稳定性好。     

甲烷磺酸铜催化合成丁酸异戊酯的性能研究

以甲烷磺酸铜作为合成丁酸异戊酯的催化剂,考察了催化剂用量、反应时间、醇酸物质的量比对酯化率的影响。实验表明,丁酸0.167mol,醇酸物质的量比1.2∶1,甲烷磺酸铜用量0.125%(基于丁酸的物质的量分数,下同),反应时间1.5～2.0h,环己烷5mL作带水剂,在回流温度下酯化率可达97.8%;与CuSO4.5H2O等其他几种Lewis酸相比,甲烷磺酸铜具有较高的催化活性,反应后易与产物分离,催化剂重复使用8次,酯化率仍达到93.0%以上。     

丁酸苄酯的催化合成研究

以丁酸、苯甲醇为原料,硫酸氢钠(NaHSO4·H2O)为催化剂合成丁酸苄酯.其优化条件为:酸醇物质的量比为1∶1.3,催化剂用量为0.2g/0.1 mol丁酸,反应温度98～125 ℃,反应时间45 min,酯化率可达98.49%.     

氨磺酸催化合成丁酸异戊酯的研究

以氨磺酸为催化剂催化合成了丁酸异戊酯,确定了酯化优化条件。实验结果表明,醇酸摩尔比值为1．8;催化剂用量1．0g;带水剂甲苯15ml（丁酸用量为0．2mol的情况下）;反应温度为110－135℃;反应时间2．0h;是最佳反应条件,酯化率98．5％。     

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.     

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.     

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.     

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。     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

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。