蜂蜜中氟胺氰菊酯残留量的HPLC测定方法

采用微量化样品处理技术处理蜂蜜样品，残留物经正己烷－丙酮提取后，进行液－液分配净化，反相液相色谱法测定氟胺氰菊酯残留量，检测波长256nm，外标法定量。测定低限为0.005mg／kg，回收率＞85％，变异系数＜3％。     

悬挂降液管塔板的冲击漏液及其对传质效率的影响

从理论上分析了悬挂式降液管塔板上产生冲击漏液的原因，并提出在塔板的受液区安装防冲漏液装置来减小冲击漏液量。在－φ500的冷模塔内以空气－水为物系测定了冲击漏液量，在－φ300的热模内以酒精－水为特系测定了塔板效率。结果表明：没装防冲击漏液装置的悬挂工降液管塔板的冲击漏液量达总液量的7％以上，而安装防冲击漏液装置的悬挂式降液管塔塔板基本上没有冲击漏液，可以提高塔板传质效率5％以上。     

气相色谱法测定玉米中乙草胺残留量

本文报道了玉米中乙草胺残留量的气相色谱测定法，样品用石油醚－丙酮提取，乙腈液－液分配净化，电子捕获检测器测定。乙草胺的最小检测量为８．６×１０＾－１２克，在玉米中最低检测浓度０．００１毫克／公斤。空白样品添加０．０４－１．００毫克／公斤的平均回收率和变异系数分别为９４．５％和２．６％。     

高效液相色谱法同时测定2，4－二硝基苯酚钾、对－硝基苯酚钾和邻－硝基苯酚钾

用高效液用色谱法同时测定２，４－二硝基苯酚钾、对－硝基苯酚钾和邻－硝基苯酚钾，相对偏差小于１％。     

碳化液中石油助长剂活性组份的测定研究

研究了测定碳化液中石油助长剂活性组份含量的方法－－酸碱滴定法的测定条件和干扰因素；确定了石油助长剂活性组份为一元弱酸盐，测得了对反应的一元弱酸的离解常数和用强碱滴定时的等当点。当取样量为50mL，碳化液中石油助长剂活性组份的含量为85mg.L^-1左右时，酸碱滴定法的标准偏差为4mg.L^-1左右，变异系数不大于5％，加标量为1至2倍时，回收率为80％左右。     

对二甲氨基苯甲醛的热容及热力学性质

用小样品量自动绝热量热装置，测定了对二甲氨基苯甲醛在８０－３６０Ｋ温区的热容，获得其固－液熔化相变的热力学参数：熔点为３４６．１５４Ｋ，熔化焓为１９．０７ｋＪ·ｍｏｌ－１，熔化熵为５５．０８Ｊ·ｍｏｌ－１·Ｋ－１。对试样的化学纯度进行了量热法研究，确定样品的纯度为９９．７３６％     

流动注射分析法测定食盐中的碘酸盐

本文采用流动注射分析法测定了食盐中的碘酸盐含量，最佳操作条件为０．１５％碘化钾－１．５％磷酸－０．１％淀粉溶液，水为载液，线性范围０．４～１００ｍｇ／ｋｇ，检测限为０．４ｍｇ／ｋｇ连续１１次测定含碘量为１８．９２ｍｇ／ｋｇ食盐样品，变异系数２．２８４％，回收率９９．８％～１００．３％。     

出口柑桔中双甲脒及代谢物残留量测定

柑桔样品中双甲脒及代射物在酸性条件下回流水解成2，4－二甲基苯胺，正己烷提取，酸，碱反复液－液分配净化，七氟丁酸酐将2，4－二甲基苯胺衍生成2，4－二甲苯七氟丁酰胺，用配有电子俘获检测器的气相色谱仪测定，外标法定量。     

液膜富集铀（VI）与水中痕量铀的测定

应用液膜技术富集水中的痕量铀（Ⅳ），研究了分离、富集铀（Ⅵ）的最佳液膜组成，实验了Ｓｐａｎ８０－ＴＢＰ－ＣＣｌ４－液体石蜡－ＨＣｌＯ４液膜混合体系的最适宜条件，用该法富集工业废水中的痕量铀（Ⅳ）富集倍数为７５以上，该法已成功地应用于测定水和废水样品中的痕量铀，相对标准偏差为２．１％，回收率为９９．０％～１００．８％。     

红外分光光度法测定PVDC树脂中的ESO和ATBC

用二硫化碳萃取PVDC树脂中的增塑剂ESO和ATBC，红外分光光度法测定，以解联立方程的方法同时求得ESO和ATBC的量。测定的相对误差：ESO为－3．5～5．5％，ATBC为－3．0～5．7％。     

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.     

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.