Mn2O3氧化法合成对氯苯甲醛

研究了以Mn2O3为氧化剂，在硫酸介质中氧化对氯甲苯合成对氯苯甲醛的工艺条件，最适宜的反应温度为343K．硫酸浓度为8．01mol／L。实验中所使用的三氧化二锰是在923K下灼烧二氧化锰得到的，用亚硫酸氢钠法分离反应物与产物。氧化反应表现出零级反应特征，反应活化能为115kJ／mol左右。     

Ce4+/Ce3+作氧化媒质间接电氧化对氯甲苯的反应动力学研究

在优化的实验条件下分别从产物和反应物2方面进行分析，系统地研究了硫酸浓度为6．425mol/L和7．7mol/L时Ce^4 /Ce^3 作氧化媒质间接电氧化对氯甲苯的有机氧化动力学，确定出总反应为 表观1级反应，并拟合出了相应的表观反应速率常数和表观活化能，当硫酸介质浓度从6．425mol/L增至7．7mol/L时表观活化能显著降低（从122－128kJ/mol降低到84－89kJ/mol）从而大大加速了化学反应速率。     

异丙醇的O3/H2O2复合氧化动力学研究

采用停流光谱仪研究了异丙醇在T=298K和pH=3～11范围内O3 / H2O2复合氧化的反应动力学.结果表明异丙醇的O3 / H2O2复合氧化反应动力学随反应体系的pH值不同而不同.在酸性和中性条件下,反应相对于O3浓度、异丙醇浓度都为1级;在碱性条件下,异丙醇较容易被O3/H2O2复合氧化降解,总反应级数为2级,相对于O3浓度、异丙醇浓度和H2O2浓度分别为1级、0级和1级,可见异丙醇的降解速率与它的浓度无关.在T=298K,当pH值从9增大到11, 反应速率常数从3486.1(mol·L-1)-1·s-1增大到38239.2(mol·L-1)-1·s-1. 表明在酸性条件下,异丙醇的O3/H2O2复合氧化是O3分子直接攻击异丙醇的反应占主导;在碱性条件下,自由基型反应占主导.     

电解法制备二氧化锰及产品纯度分析

采用恒电流法电解硫酸—硫酸锰混合溶液制备二氧化锰 ,并测定了电解液浓度、酸度、温度以及电极材料对电解产品转化率和纯度的影响。通过正交试验确定以石墨为阴极、铂为阳极、硫酸锰浓度为1.5mol·L-1、硫酸浓度为 0 .3mol·L-1、在 90℃条件下为电解的最佳反应条件。     

低品位软锰矿降解糖蜜酒精废液中焦糖色素的脱色动力学

用合成的双倍焦糖色素模拟糖蜜酒精废液中的焦糖色素,研究了硫酸介质中低品位软锰矿氧化降解焦糖色素的脱色动力学,考察了焦糖色素初始浓度、硫酸浓度、软锰矿用量和反应温度对焦糖色素降解脱色速率的影响. 结果表明,焦糖色素的降解脱色速率随焦糖色素初始浓度、硫酸浓度、软锰矿用量和反应温度的增加而增加. 对实验数据进行拟合,得到了焦糖色素降解脱色动力学模型,其脱色过程的表观活化能为24.4 kJ/mol,焦糖色素、硫酸和软锰矿的表观反应级数分别为2.0, 0.58和1.09.     

伴有辅酶再生过程的Saccharomyces cerevisiae B5不对称还原2'-氯-苯乙酮的催化反应动力学

对以5%(体积比)乙醇为辅助底物的伴有辅酶再生过程的SaccharomycescerevisiaeB5不对称还原2'-氯-苯乙酮制备手性药物中间体R-2'-氯-1-苯乙醇的生物催化反应建立了描述底物消耗和产物合成的动力学模型.考察了反应过程中辅酶的种类和含量,以及底物和产物随时间的变化量.研究表明,参加反应的还原剂是辅酶Ⅰ.当底物初始浓度≤8.09mmol·L-1,可不考虑底物对微生物的毒害作用,反应可看作两个均符合顺序反应机制的氧化还原反应的耦联.通过实验数据对动力学方程式的拟合,得到动力学参数Vm1=8.0×10-4mol·L-1·h-1,KmB1=9.0×10-4mol·L-1,KiA1=2.0×10-6mol·L-1.动力学模型模拟计算结果与实验值能较好地吻合.     

空气氧化对氯甲苯制备对氯苯甲醛

以醋酸为溶剂 ,Co/Mn/Br混合物作催化剂 ,常压下空气直接氧化对氯甲苯制对氯苯甲醛 ,在反应温度 80°C,反应时间 5 h,催化剂质量分数占 3 %,空气流量 1 .0 L/min,底物对氯甲苯体积分数为 2 0 %时 ,对氯苯甲醛选择性达 6 0 %,实际收率 2 0 %,产品纯度 99%以上。     

碘仿电解合成的机理研究

采用循环伏安法分别研究了铂电极在 0 .1 mol· L- 1 Na2 CO3+0 .0 5mol· L - 1 KI,0 .1 mol· L - 1Na2 CO3+0 .0 5 mol· L- 1 KI+0 .5mol· L- 1 乙醇 ,0 .1 mol· L- 1 Na2 CO3+0 .0 5 mol· L- 1 KI+0 .5 mol· L- 1丙酮溶液中的电化学行为 ,发现含 I- 体系的阳极氧化反应十分复杂 ,除了 I- 被电氧化为 I2 外 ,同时还发生生成 IO3- 等含碘高价化合物的电氧化反应 ,此外电氧化反应过程中还存在多个后续化学反应 ;电化学阴极还原反应则较为简单。中间产物 IO-的作用非常关键 ,IO-攻击甲基酮中 - CH3与 >C=O之间的 C- C键而生成碘仿 ,碘仿电解合成反应中存在着复杂的竟争反应现象。通过循环伏安曲线分析还发现电极过程的控制步骤并非为简单的传质步骤     

空气催化氧化亚硫酸铵制备硫酸铵

采用单因素实验研究了亚硫酸铵初始浓度、反应温度、空气流量、催化剂硫酸钴浓度等因素对催化氧化亚硫酸铵的效率的影响.结果表明,低浓度亚硫酸铵较易氧化,亚硫酸铵浓度越高,氧化越困难;反应的最佳温度为50℃,氧化速率随着空气流量和催化剂硫酸钴浓度的增加而加快.通过正交实验确定最佳氧化反应条件为:亚硫酸铵初始浓度1.1 mol·L-1,催化剂硫酸钴浓度0.015 mol·L-1,反应温度50℃.     

萃取-膜蒸馏法处理钛白废酸的研究

提出了三异辛胺-仲辛醇-航空煤油体系萃取硫酸与减压膜蒸馏浓缩相结合的钛白废酸治理新方案。对萃取工艺参数、膜蒸馏浓缩稀硫酸的基本规律及萃取回收硫酸的浓缩程度进行了研究。结果表明:1.49mol·L-1的钛白废酸经8级萃取和6级反萃取,酸回收率可达92.15%,稀硫酸浓度为1.21mol·L-1,再经减压膜蒸馏浓缩可得到10.82mol·L-1(质量分数67.3%)的硫酸,达到了返回钛白生产循环使用的要求。     

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.     

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.     

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。