全自动浓缩仪浓缩土壤中有机氯农药研究

使用全自动定量浓缩仪建立土壤中有机氯农药提取液的浓缩方法，通过相关试验确立了浓缩条件，使有机氯农药的加标回收率在两次浓缩过程中分别处于82．6％～105．3％和90．6％～103—1％之间，同时完成溶剂转换工作，为土壤有机氯农药分析中的样品浓缩问题建立了一套自动化程度高，加标回收率高，人为干扰因素小的解决方案。     

气相色谱-质谱法同时测定空心胶囊中32种有机氯农药

建立了测定空心胶囊中32种有机氯农药的气相色谱—质谱法。样品经QUECHERS法前处理,以HP—5MS毛细管柱为分析柱,气相色谱—质谱法进行检测,外标法定量。结果表明：32种有机氯农药在1～20μg/mL浓度范围线性关系良好,相关系数为0.9995～1.0000。在1、4和8μg/mL加标水平下,32种有机氯农药的回收率为85.7%～104.8%,相对标准偏差为0.64%～2.94%。本方法快速、简便、准确、灵敏,适用于空心胶囊中有机氯农药的日常检测。     

气相色谱法测定天然矿泉水中15种有机氯农药

通过优化萃取和净化条件,建立了一种快速测定天然矿泉水中15种有机氯农药的气相色谱方法。采用正己烷萃取和弗罗里硅土固相萃取柱对样品净化,毛细管柱分离,用配有电子捕获检测器的气相色谱进行检测,平均加标回收率为86.4％～108.0％,相对标准偏差（ RSD, n＝11）为0.95％～4.75％,检出限为0.69～1.85 ng/L。方法简单、快捷、经济,适应于天然矿泉水中的15种有机氯农药的测定。     

气相色谱法测定石斛中的农药残留

建立了毛细管柱气相色谱法同时测定石斛中18种有机氯和拟除虫菊酯类农药残留的方法。石斛鲜条经匀浆,乙腈提取、净化后,选用HP-5毛细管色谱柱,通过柱程序升温,进行检测,外标法定量。结果显示：18种农药取得很好的分离效果,农药残留量在0．008～0．4Ixg／mL范围内方法的线性良好,相关系数为0．9961-0．9999,18种混合农药加标量为0．05mg／kg和0．5mg／kg时,加标回收率在75．3％-109．2％之间,相对标准偏差小于10％,检出限0．001-0．01mg／kg。     

有机氯农药、有机磷农药的EIMS、NCIMS和PCIMS质谱

阐述31种农药在3种电离方式：电子轰击质谱(EIMS)、正化学电离质谱(PCIMS)和负化学电离质谱(NCIMS)下的质谱特征和裂解规律，为农药残留的筛选和结构确证奠定基础。分别测定18种有机氯农药、13种有机磷农药的电子轰击质谱(EIMS)，正化学电离质谱(PCIMS)和负化学电离质谱(NCIMS)。在EIMS中，有机氯农药主要产生[M—Cl]^ 、[M—HCl]^ 离子，有机磷农药主要产生磷酸基和磷酸酯基离子；在NCIMS中，[Cl]^-或[HCl2]^-离子是有机氯农药的基峰，有机磷农药主要产生磷酸酯基负离子，某些芳香硫代磷酸酯还可产生重排离子；而在PCIMS中．大多数农药的灵敏度较低．没有观察到质谱。     

气相色谱法测定大米中有机氯农药残留量

建立了大米中9种有机氯农药毛细管气相色谱-电子捕获检测器检测方法.应用HP-5弹性石英毛细管柱,经柱程序升温技术分离各组分,以峰面积外标法定量,取得了较好的效果.实验方法的加标回收率在(89.3～104.2)%,相对标准偏差为(1.36～4.01)%.从而成功地建立了大米中9种有机氯农药残留测定的好方法.     

GC—MS同位素稀释法测定环境基质中的有机氯农药

采用气相色谱-质谱联用同位素稀释法对各种环境基质中的23种有机氯农药进行检测,能满足有机分析的基本要求,各种基质的加标回收率在70％～125％之间,取10ppb标准溶液经重复6次测定,能得到较好的精密度,其RSD小于20％。该方法适合各种环境基质中的有机氯农药的分析测定。     

凝胶渗透色谱净化-气相色谱测定糙米中7种常见有机磷农药残留

提供7种常见有机磷农药在糙米中同时测定的方法。前处理使用凝胶渗透色谱(GPC)净化技术，毛细管气相色谱火焰光度检测器测定，GC／MS进行确证测定7种常见有机磷农药(包括敌百虫、敌敌畏、甲胺磷、甲基嘧啶磷、二嗪磷、对硫磷、水胺硫磷)。并且采用GPC研究了7种有机磷农药在凝胶渗透色谱柱上的流出规律及净化效果，凝胶渗透色谱采用的流动相为环己烷一二氯甲烷(1：1)，最佳流速是5ml／min，收集最佳时间是14—25min。经方法的线性试验、精密度试验、检测限试验，验证了方法的可行性。方法最小检出质量比范围县1-8μg／kg,精密度为0．2％～10％。精密度试验的变异系数满足农药多残留痕量分析的要求。     

气质联用法测定生菜中有机氯类农药残留

建立了生菜中有机氯类农药残留的气质联用分析方法。样品采用乙腈提取,石墨化碳/氨基复合萃取小柱净化,气质联用仪分析有机氯类农药。该方法的回收率在83.9%~1 09.5%之间,线性相关系数大于0.999,1 1种有机氯类农药的检出限在0.003 0~0.01 2 5 m g/kg。方法准确可靠,可应用于生菜中多种有机氯农药的测定。     

蔬菜中20种有机氯类农药残留气相色谱分析方法的研究

对国标气相色谱法检测蔬菜中20种有机氯农药残留的方法做了改进,试样前处理改用乙腈溶剂在弗洛里硅土固相萃取柱上净化;使用CP-Sil 24CB毛细管色谱柱分离,ECD测定。结果表明,在所建立的分析下,20种有机氯农药残留能够很好分离。工作曲线有良好的线性。检出限在0.1～0.8μg/kg范围内,回收率在80.5%～105.6%之间,方法的变异系数为0.36%～12.9%。该法简单、快捷、灵敏、准确,满足日常蔬菜中20种有机氯农药残留的常规分析检测要求。建立的改进方法适合大宗试样的分析。     

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.     

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.     

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。