高效液相色谱法测定有机硅涂料中多环芳烃

建立了一种采用高效液相色谱检测有机硅涂料中多环芳烃的方法，该方法所用色谱柱为多聚C18（LC—PAH）柱，流动相为乙腈／水，采用梯度淋洗方式，开始时为40％乙腈，28min后变为82％乙腈，48min后变成100％乙腈，保持8min。该方法的线性范围为0．10-200mg／L，线性相关系数为0．9993-1．0000，平均回收率为69．59％～100．31％，精密度实验RSD为1．34％～7．84％，检测限（S／N=5）为0．05—0．10mg／L。该方法完全可以满足有机硅涂料中多环芳烃的检测要求。     

柱前衍生高效液相色谱法分析农用链霉素

采用柱前衍生，使用C18反相柱和二极管阵列检测器，以乙腈-0．2％庚磺酸钠溶液（体积比为20：80）为流动相，柱温30℃，流量0．5mL／min，检测波长330nm，外标法对农用链霉素进行定量分析。其标准偏差为0．25，变异系数为0．35％，平均回收率为99．76％，相关系数r为0．9992。与生物效价法比较，该方法操作简单快速，定量准确可靠，适用于产品的常规分析和质量控制研究。     

噻虫啉的反相高效液相色谱分析

建立了一种用高效液相色谱测定噻虫啉的定量分析方法，采用C18 HPLC色谱柱，以甲醇-水（体积比为70：30）为流动相．选择238nm为检测波长进行检测。结果表明，该方法的标准偏差为0．00103，变异系数为0．1042％。相关系数为0．99947，平均回收率为99．86％。     

氟吡磺隆高效液相色谱分析

采用SB-C18 HPLC色谱柱，以甲醇，水（90，10）为流动相，选择254nm为检测波长对氟吡磺隆进行分离和定量分析检测。结果表明本方法的标准偏差为0．0017，变异系数为0．36％，相关系数R^2为0．9999，回收率为98．85％-101．73％。     

硫丹原药的气相色谱分析

论述了采用毛细管柱为分离柱，邻苯二甲酸二丁酯为内标物和FID检测器，对硫丹原药进行定量分析的方法。本方法标准偏差为0．15，变异系数为0．16％，回收率在99．0％～101．5％之间，平均回收率为100．7％，线性相关系数为0．9998。     

HPLC法测定通关藤中绿原酸的含量

应用HPLC法测定通关藤中绿原酸的含量。实验采用Agilent ZOBAX Eclipse C18（150mm×4．6mm，5μm）色谱柱，以乙腈：0。4％磷酸=8：92为流动相，流速0．6mL／min，检测波长327nm，柱温为室温。用外标法测定，绿原酸的平均回收率为98．74％，其检测线性范围为0．672-0．056μg。结果表明，方法简便易行，结果准确可靠。     

氟环唑高效液相色谱分析

建立了一种用高效液相色谱测定氟环唑的定量分析方法。采用C18HPLC色谱柱，以乙腈／水(85／15)为流动相．选择205nm为检测波长进行检测。结果表明本方法的标准偏差为0．14％．变异系数为0．16％，相关系数γ为0．9996，平均回收率为99．91％?     

氟吗啉水分散片剂高效液相色谱分析方法

采用高效液相色谱法外标法定量分析氟吗啉水分散片剂。该方法以甲醇＋水（50＋50）作为流动相，流速为0．5ml／min，C18反相色谱柱，柱温为25℃，检测波长为230nm。本方法的回收率大于99％，变异系数小于0．3％。     

吡氟氯禾灵的高效液相色谱法拆分与测定

在流动相为正庚烷-异丙醇-三氟乙酸（体积比为99．3：0．5：0．2），流速为0．6mL／min，检测波长为278nm，柱温为10℃的分析条件下，利用手性色谱柱Nucleosil chiral-2成功实现了吡氟氯禾灵对映体的手性分离，并建立了对有活性的尺型异构体的定量测定方法。     

25%炔螨特乳油的气相色谱分析

采用气相色谱法，以二十二烷为内标物，OV－101为填充柱，用FID检测器进行25％炔螨特含量的分析。本方法的标准偏差为0．1199，变异系数为0．4737％，线性相关系数为0．9989，回收率为98．74％－100．1％。     

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.     

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.