乙醛肟的气相色谱分析

本文介绍用１０％ＰＥＧ２０Ｍ，长３ｍ内径３ｍｍ的不锈钢填充柱，以正庚醇为内标物，在１２０℃的柱温下用ＦＩＤ检测器对乙醛肟进行定量分析。该法的变异系数为０．７６％，平均回收率９９．８７％，线性相关系数０．９９９７。     

灭多威肟的气相色谱分析

灭多威肟是合成氨基甲酸酯农药灭多威的中间体,纯品为白色晶体,有刺激性气味。在灭多威合成过程中,作为生产控制的需要,应对其进行定量分析。关于灭多威肟的定量分析方法,国内尚未有公开报道,根据国外文献记载,其分析方法有反相高压液相色谱法、分光光度法等。根据我们国家企业的实际情况和生产控制的需要,我们对灭多威肟的气相色谱分析方法进行     

35%赛铃灵乳油的气相色谱和紫外分析

３５％赛铃灵乳油是由甲基对硫磷、硫丹和灭多威组成的复配制剂。本文报道了其分析方法，其中甲基对硫磷和硫丹用气相色谱法分析，灭多威薄层色谱－紫外比色法分析。本方法的标准偏差和回收率为０．１２和９８．８２－１０１．２０％，０．０７和９９．２３－１００．０８％，以及０．０２和９９．９１－１００．０５％。     

乙醛肟气相色谱分析测试研究

本文通过气相色谱法，用ＴＣＤ检测器，对乙醛肟进行了分析，该方法在０～１２０ｇ／Ｌ范围内其相关系数Ｒ２＝０．９９９９，标准偏差为０．１％，平均回收率为９９．５％。本文还对ＧＣ方法与ＨＰＬＣ方法做了比较。     

邻甲苯甲醛的气相色谱分析

研究了邻甲苯甲醛的气相色谱分析条件,分别选用８％ＯＶ－２１０、１０％ＱＦ－１和８％ＤＣ－２００为固定相,测定邻甲苯甲醛的含量。结果表明,该方法快速、准确。标准偏差小于０．２％,回收率１００．９％～１０１．１％。     

邻甲苯甲醛的气相色谱分析

研究了邻甲苯甲醛的气相色谱分析条件，分别选用８％ＯＶ－２１０、１０％ＱＦ－１和８％ＤＣ－２００为固定相，测定邻甲苯甲醛的含量。结果表明，该方法快速、准确、标准偏差小于０．２％，回收率１００．９－１０１．１％。     

无水乙醛肟的制备

乙醇肟是生产农药灭多威的中间体,也是重要的有机合成试剂和分析试剂[1]。用于有机合成的乙醛后有时必须要求无水（如：与酰氯和异氰酸酯的反应）,而目前国内市场提供的乙醇肟为含量40％左右的水溶液,不能满足需要,为此,我们对无水乙醛股的制备做了研究。无水乙醛肟可由相应乙醛肟水溶液制备。乙醛肟水溶液由盐酸羟胺或硫酸羟胺与乙醛反应而得。本文用盐酸羟胺和乙醛反应所得已醛肟水溶液经萃取、分离、蒸馏制备无水乙酸肟,取得了较好的结果。1实验部分1.1试剂与仪器．乙醛为分析纯;盐酸羟胺、氢氧化钢和二氯甲烷均为化学纯。CR－3…     

丁草胺,恶草酮复配制剂的气相色谱分析

介绍了除草剂丁草胺和恶草酮复配制剂的气相色谱分析方法。选用１０％ＱＦ－１／Ｃｈｒｏｍｓｏｒｂ ＷＡＷ ＤＭＣＳ色谱柱，以邻苯二甲酸二甲酯为内标物，进行定量分析测定。丁草胺和恶草酮的线性回归系数分别为０．９９９５和０．９９９８，方法回收率在９８．８％￣１００．７％之间，标准偏差小于０．１４，变异系数优于０．７０％。     

灭多威原药及乳油的气相色谱分析

本文选取了５％ＯＶ－１０１／ＣｈｒｏｍｏｓｏｒｂＷ－ＡＷＤＭＣＳ（６０～８０目）为色谱柱，磷酸三丁酯为内标物，对灭多威原药及乳油进行气相色谱分析。结果表明：标准偏差为０．９４，变异系数为１．０１％。     

触变性酮肟型单组分有机硅密封胶的研制

研究了触变性酮肟型有机硅密封胶的交联体系和填料体系的组成及其对密封胶表干时间，电绝缘性能，力学性能和触变性能的影响，得出结论：交联体系中锡催化剂的适宜用量为０．４－０．５份，气相ＳｉＯ２和活性ＣａＣｏ３填料可提高密封胶的强度，且赋予其优良的触变性能。     

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.     

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.     

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.     

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.     

Novel polyurethane coating technology through glycidyl carbamate chemistry

Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.     

Highly moisture-proof polysilsesquioxane coating prepared via facile sol-gel process

A highly moisture-proof polysilsesquioxane coating was obtained from a new bis-silylated precursor, which was synthesized from 3-aminopropyltriethoxysilane (APTES) and m-xylylene diisocyanate (m-XDI) in tetrahydrofuran (THF) and verified by ¹H MAS NMR. For direct comparison purposes, an SiO₂ coating was also prepared by the Stöber method using tetraethoxysilane (TEOS) as the reactant. Interestingly, the coating obtained from the polysilsesquioxane sol exhibited a much higher moisture resistance capability than its counterpart, which was attributed to its more compact feature between nanoparticles as characterized by N₂ absorption experiment and transmission electron microscopy (TEM). Furthermore, its high transparency of about 92% showed potential for application in the protection of optical crystals.