固体超强酸La3+-SO42-/TiO2-Fe2O3催化合成对羟基苯甲酸丁酯

以固体超强酸La3+-SO42-/TiO2-Fe2O3为催化剂合成了对羟基苯甲酸丁酯,考察了原料配比、催化剂用量、反应温度和反应时间等因素对产品收率的影响。试验结果表明:La3+-SO42-/TiO2-Fe2O3是合成对羟基苯甲酸丁酯的良好催化剂,当n(丁醇)/n(对羟基苯甲酸)=4.0,催化剂用量为对羟基苯甲酸质量的6%,反应温度120℃,反应时间4.0 h,对羟基苯甲酸丁酯的收率达到89.27%。     

催化合成对羟基苯甲酸戊酯的研究

以戊醇和对羟基苯甲酸为原料,黄铁矾作催化剂,催化合成对羟基苯甲酸戊酯。研究了反应温度、反应时间、投料比和催化剂用量等因素对酯化反应的影响。结果表明:反应的酸醇比为1∶3,催化剂用量1.5g,反应温度110～160℃,反应2h,酯产率可达93.3%。     

超强酸La~(3+)-SO_4~(2-)TiO_2合成对羟基苯甲酸丁酯

以稀土固体超强酸La3 + SO42 - TiO2 为催化剂,以对羟基苯甲酸与正丁醇为原料催化合成对羟基苯甲酸丁酯,研究了原料量比、催化剂用量和反应时间诸因素对产品收率的影响。试验结果表明:La3 + SO42 - TiO2 是合成对羟基苯甲酸丁酯的良好催化剂,在n(丁醇) n(对羟基苯甲酸) =4 0 ,催化剂的用量为对羟基苯甲酸质量的3 5 % ,反应时间4 0h ,反应温度12 0℃～130℃,对羟基苯甲酸丁酯的收率达到92 7%。     

对甲基苯磺酸催化合成4-乙酰氧基苯甲酸的研究

以对羟基苯甲酸和乙酸酐为原料,采用对甲基苯磺酸作催化剂合成4-乙酰氧基苯甲酸,考察了反应温度、反应时间、催化剂用量对产品的影响。实验结果表明酰化反应的优化条件n(对羟基苯甲酸)∶n(乙酸酐)∶n(对甲苯磺酸)=1∶2∶0.025,反应时间30min,反应温度80~89℃,产率达91.63%。     

甲苯-4-磺酸催化高效合成尼泊金正丁酯防腐剂

以对羟基苯甲酸和正丁醇为主要原料,甲苯-4-磺酸为催化剂,正丁醇为带水剂,催化合成尼泊金正丁酯。考察了原料对羟基苯甲酸和正丁醇的摩尔比、催化剂用量、反应温度和反应时间等对反应的影响。结果表明,适宜的反应条件:以0.02 mol对羟基苯甲酸计,n(正丁醇)∶n(对羟基苯甲酸)=4∶1,m(甲苯-4-磺酸)∶m(对羟基苯甲酸)=0.12∶1,反应温度140℃,反应时间3 h。该条件下,重复实验3次,尼泊金正丁酯收率均达99%以上。     

磺酸树脂催化合成尼泊金酯的研究

以对羟基苯甲酸(PHBA)和丁醇为原料,用磺酸树脂作催化剂,催化合成了尼泊金丁酯,优化反应条件为:n(丁醇):n(对羟基苯甲酸)=5:1,催化剂磺酸树脂的用量为对羟基苯甲酸质量的21%,反应温度为回流温度,反应时间为5 h。尼泊金丁酯收率可达82.6%,催化剂可重复使用,产品结构用红外光谱图进行了表征。该方法也适合于合成尼泊金戊酯。     

磷钨酸铯作催化剂合成对羟基苯甲酸正丁酯

本文介绍了磷钨杂多酸铯的制备方法，并用其作催化剂合成了对羟基苯甲酸正丁酯，确定了合成对羟基苯甲酸正丁酯的最佳工艺条件；正丁醇，对羟基苯甲酸与甲苯的物质的量为4：1：2，催化剂用量为对羟基苯甲酸质量的10%左右，反应时间4h，反应温度130℃左右，对羟基苯甲酸正丁酯的收率为97.9%。     

相转移催化合成对羟基苯甲酸苄酯的研究

用对羟基苯甲酸和氯化苄为原料,以氯化三乙基苄基铵为相转移催化剂合成了对羟基苯甲酸苄酯。通过实验考察了反应温度、催化剂用量、反应时间及物料配比等因素对反应的影响。结果表明,最佳反应条件是：反应温度145℃,催化剂用量7．54mmol,反应时间2．5h,氯化苄与对羟基苯甲酸的量的比为2：1。在此条件下,收率在95．5％以上。产品熔点为109～111℃,并通过元素分析、红外光谱分析、核磁氢谱对其进行了结构表征。     

2,6-二羟基苯甲酸合成工艺研究

为提高2,6-二羟基苯甲酸的合成收率,采用有机溶剂法制备了2,6-二羟基苯甲酸。探讨了溶剂种类,催化剂种类及用量,反应温度,反应压力及反应时间对产品收率的影响。确定以N,N-二甲基甲酰胺（DMF）为溶剂、K2CO3为催化剂,在140℃、10 atm压力下反应6 h,2,6-二羟基苯甲酸的单程收率可达35%以上,产品纯度95%以上。     

H_3PW_(12)O_(40)/TiO_2催化合成对羟基苯甲酸丁酯的研究

采用溶胶-液相法制备了H3PW12O40/TiO2复合催化剂,用FT-IR分析方法对催化剂进行了结构表征。以对羟基苯甲酸和正丁醇为原料合成了对羟基苯甲酸丁酯,考察了反应物配比、催化剂用量、反应时间及催化剂的重复使用性能对产品收率的影响。实验结果表明,合成对羟基苯甲酸丁酯的较优反应条件为:对羟基苯甲酸0.1 mol,n(对羟基苯甲酸)∶n(正丁醇)=1.0∶5.0(摩尔比),催化剂的用量为1.2 g,反应时间4.0 h。上述条件下,对羟基苯甲酸丁酯的收率可达85.0%以上。     

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.     

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.     

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。     

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.     

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。