过硫酸钾存在下的盐酸胺碘酮极谱催化波及其应用

基于K2S2O8存在下盐酸胺碘酮(ADHC)产生的极谱催化波,拟定了测定ADHC的新方法。在0.15mol/LKH2PO4Na2HPO4(pH5.6) 8.0×10-5mol/LK2S2O8底液中,ADHC于-1.32V(vs.SCE)产生的极谱催化波的二阶导数峰电流ip″与其浓度在8.0×10-8～4.0×10-7mol/L及4.0×10-7～8.0×10-5mol/L呈良好的线性关系,其线性回归方程分别为ip″/μA·s-2=-3.95 9.51×107cADHC(r=0.9939,n=7),ip″/μA·s-2=104.6 2.92×107cADHC(r=0.9958,n=7),检出限为2.70×10-8mol/L。该催化波的分析灵敏度比相应还原波提高了5倍左右,该方法用于测定ADHC的含量,结果满意。     

铜（Ⅱ）-孔雀石绿配合物极谱吸附波的研究

在0.5mol/L NH4C l溶液中,用单扫描示波极谱法在-0.69V（vs.SCE）可获得灵敏的铜-孔雀石绿（MG）配合物极谱吸附波,其二阶导数波峰高与孔雀石绿浓度在2.5×10-7-1.25×10-4mol/L范围内成正比关系,检出限为1.0×10-7mol/L,测得电活性配合物组成为Cu2＋：MG=1：4。该方法用于水样、土样中孔雀石绿的测定,回收率分别为95.2%-108.0%和92.0%-106.0%。     

培氟沙星在碳糊电极上的阳极吸附伏安法研究

在0.40 mol/L的NaAc-HAc(pH 4.9)缓冲液中,使用JP-303极谱分析仪,培氟沙星在碳糊电极(CPE)上有一灵敏的吸附伏安氧化峰,峰电位为1.03 V(vs.SCE)。该氧化峰的二阶导数峰电流与培氟沙星的浓度在8.0×10-9~8.0×10-7mol/L(富集90 s)范围内成良好的线性关系,相关系数r为0.998,检出限为4.0×10-9mol/L(S/N=3,富集110 s)。探讨了培氟沙星在碳糊电极上的伏安性质和电极反应机理,并且成功应用于胶囊中培氟沙星含量的测定。     

废水及空气中微量苯胺的极谱法分析

用极谱方法分析环境中的苯胺污染物的含量,苯胺重氮化反应产物再与亚硫酸钠、甲醛的反应物有一灵敏的二阶导数极谱波,峰电位-0.71V(vs、SCE)。研究了影响因素,优化了分析条件。线性范围在8.0×10-7～5.0×10-4mol/L,可用于废水与空气中微量苯胺的测定。     

非甾体抗炎药布洛芬的含量测定

用氧化剂存在时布洛芬产生的极谱催化波提高分析灵敏度,用线性单极扫描谱法实现快速测定。在0.08mol/L HAc-NaAc(pH=4.2)支持电解质中,布洛芬于-1.06 V处产生一极谱波,当氧化剂K2S2O8存在时,K2S2O8氧化布洛芬羰基还原中间体自由基,使布洛芬再生,产生布洛芬的极谱催化波。其催化波的二次导数峰电流ip″与浓度在4.0×10-8~5.0×10-7mol/L范围内呈线性关系(r=0.9980,n=8),检测限为2.0×10-8mol/L。该方法可用于药物制剂中布洛芬含量的测定。     

2-羟基-4-正辛氧基二苯甲酮的极谱行为

用线性扫描极谱法研究了在不同缓冲体系中2-羟基-4-正辛氧基二苯甲酮(简称BP-12)的极谱行为。实验表明,在2mol/L的H2SO4溶液中,BP-12的二阶导数峰电位为-0.92V,BP-12在两个浓度范围内与峰电流呈线性关系。在3×10-5~4×10-5mol/L的范围内,线性方程为ip″(nA/s2)=-2796.8 1.123×108c(mol/L),相关系数为0.9915;在1×10-6~9×10-6mol/L范围内,BP-12的浓度的对数值与电流成线性关系,线性方程为ip″(nA/s2)=669.60 94.69lgc(mol/L),相关系数为0.9972。BP-12的常规循环伏安曲线表明,该极谱波为不可逆还原波。初步讨论了电极反应机理。     

铜(Ⅱ)-抗坏血酸-硫酸-硫氰酸钾极谱络合吸附波研究

用单扫描极谱法研究了Cu(Ⅱ)-H2SO4-硫氰酸钾体系的伏安行为,发现铜(Ⅱ)在抗坏血酸-H2SO4-硫氰酸钾试剂存在下,于-0.55 V(vs·SCE)左右产生一尖锐、灵敏的极谱波。经实验确定的最佳测定条件为:2.5 mol·L-1硫酸2m L,1%硫氰酸钾2 m L,10%抗坏血酸5 m L,铜(Ⅱ)的浓度在6.250×10-7~4.375×10-6mol·L-1范围内与相应的峰电流成线性关系好,回归方程为ip=348.98CCu(mol·L-1)-283.64,线性相关系数R为0.9993;最小检出浓度为4.0×10-7mol·L-1。方法用于人发中铜含量的测定,测定值与原子吸收光谱法测定值基本一致,相对标准偏差(n=6)为2.7%~4.1%,加标回收率96.2%~102.3%。     

酶催化光度法测定药物中的对乙酰氨基酚

基于对乙酰氨基酚对牛血红蛋白模拟酶催化体系的抑制作用,建立了一种简单、灵敏的酶催化光度法测定对乙酰氨基酚的新方法。研究了该抑制反应的最佳实验条件及动力学行为,测定的线性范围为4.72×10-7~9.45×10-5mol/L,检出限为1.13×10-8mol/L。对浓度为4.72×10-6mol/L的对乙酰氨基酚进行11次平行测定,其相对标准偏差为2.1﹪。该方法可用于对乙酰氨基酚片中对乙酰氨基酚含量的测定。     

维生素B1、维生素B2、维生素BC的极谱分析法

维生素B1、维生素B2、维生素BC混合物在pH为6.0的NaH2PO4-Na2HPO4缓冲溶液中均各自产生灵敏的极谱吸附波,且峰电位各不相同,依次为-1.5 V(vs.SCE)、-0.48 V(vs.SCE)、-0.90 V(vs.SCE)。且混合物浓度在1×10-4～6×10-2mol/L范围内维生素B1、维生素B2、维生素BC均与峰电流有良好的线性关系,线性系数分别为:0.9994、0.9960、0.9992,混合物的检出限为5×10-6mol/L。     

氯诺昔康的电化学行为及测定

建立灵敏快速测定氯诺昔康的新方法。用线性单扫描极谱法实现快速测定。结果表明,在0.06 mol/LHAc-NaAc(pH 4.5±0.1)缓冲溶液中,氯诺昔康于-1.25 V(vs.SCE)处产生一灵敏的极谱催化氢波,其二阶导数峰电流与氯诺昔康浓度在4.0×10-8~6.0×10-6mol/L范围内呈线性关系(r=0.9880,n=10),检出限为2.0×10-8mol/L。该方法可用于药剂中氯诺昔康的测定。     

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料，介绍了2005—2006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生产量以及各国塑料制品的进出口情况。作为对比，介绍了中国塑料的生产情况。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（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序，对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008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、不饱和聚酯树脂、环氧树脂)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.