气相色谱法测定香附挥发油中α-香附酮的含量

建立了香附挥发油中α-香附酮的气相色谱测定方法。采用氢火焰离子化检测器(FID),DB-5毛细管色谱柱(30m×0.320mm×0.25mm)进行分离。色谱柱起始温度150℃,以5℃/min恒速升温至260℃,在260℃下恒温5min;进样口:260℃;检测器:280℃。结果:α-香附酮在30~650mg/mL范围内有良好的线性关系,相关系数0.999,相对标准偏差RSD2%,回收率在95%~105%。此方法准确、可靠,可用于香附挥发油中α-香附酮的分离分析。     

液相色谱法测定38%硝·灭·氰草津可湿性粉剂

建立一种同时分析硝磺草酮、莠灭净、氰草津的高效液相色谱法。采用高效液相色谱法,以乙腈+水为流动相,使用以ODS(5μm)为填充物的不锈钢柱和具有可变波长紫外检测器,在250 nm波长下对试样中硝磺草酮、莠灭净、氰草津进行高效液相色谱分离和外标法定量。该方法操作简便、快速,方法稳定性、重现性和准确度高,可以满足硝磺草酮、莠灭净、氰草津的定性和定量分析。     

顶空气相色谱法测定荷叶提取物中11种有机溶剂的残留量

目的 :建立顶空气相色谱法,测定荷叶提取物中甲醇、乙醇、乙酸乙酯、正丁醇、异丙醇、三氯甲烷、二氯甲烷、正己烷、丙酮、苯和2-丁酮的残留量。方法:采用顶空气相色谱法,色谱柱为Agilent DB-624毛细管柱(30m×0.32 mm×1.80μm),二甲基亚砜(DMSO)为溶解介质,FID检测器;进样口温度250℃;检测器温度250℃;载气为高纯氮气,流速为2 m L/min;柱温为程序升温,起始温度为40℃,保持10 min,以8℃·min-1升温至130℃,保持10 min。结果:该法线性关系良好,r在0.998~0.9997之间;平均回收率为90.0%~101.7%;RSD均小于5%。结论:该方法操作简便快速,准确度高,可作为荷叶提取物有机溶剂残留物的测定方法。     

气相色谱法测定西格列汀原料药中6种残留溶剂

采用气相色谱法检测西格列汀原料药中四氢呋喃、乙酸乙酯、丁酮、二氯甲烷、甲苯、N,N-二甲基甲酰胺。色谱条件为DB-WAX(30m×0.32mm×0.5μm)毛细管色谱柱;载气采用高纯氮气,流速为1mL/min;检测器为氢火焰离子化检测器,检测器温度为250℃,进样口温度为200℃;程序升温,分流比10∶1,进样量1μL。该方法操作简便、稳定、重复性好,可用于西格列汀原料药中上述6种残留溶剂的测定。     

异丁酰胺的气相色谱分析方法研究

采用气相色谱法,用Agilent Q 10.0 m×320μm×20.0μm毛细柱,FID检测器对异丁酰胺进行定量测定。进样口温度218℃,检测器温度270℃,柱温230℃,采用高纯氮气为载气,流速34 cm/min,分流比20∶1的操作条件下,利用外标法,实验结果表明,该分析方法的线性相关系数为0.996 3,标准方差为0.213 1,变异系数为0.021 3%,平均回收率为99.99%。     

17%烯草酮·乙羧氟草醚乳油高效液相色谱分析

建立一种对17%烯草酮·乙羧氟草醚乳油中的有效成分同时进行分离和测定的正、反相高效液相色谱方法，并考察正、反相高效液相色谱法对烯草酮与乙羧氟草醚的检测差异。正相方法采用Syncronis Silica不锈钢柱和紫外检测器，在波长230 nm条件下，以二氯甲烷-正己烷-冰乙酸(28∶70∶2，体积比)为流动相，对试样中烯草酮和乙羧氟草醚的含量进行分离和定量分析；反相方法采用安捷伦SB-C18不锈钢柱和紫外检测器，在波长230 nm条件下，以乙腈-1%冰乙酸水溶液(80∶20，体积比)为流动相，对试样中烯草酮和乙羧氟草醚的含量进行分离和定量分析。正相方法中烯草酮和乙羧氟草醚的标准偏差分别为0.02和0.04，相对标准偏差分别为0.18%和0.76%，平均回收率分别为99.64%和99.24%，线性相关系数均为0.999 5；反相方法中烯草酮和乙羧氟草醚的标准偏差分别为0.03和0.01，相对标准偏差分别为0.29%和0.14%，平均回收率分别为98.36%和99.49%，线性相关系数分别为0.999 5和0.999 3。2种方法均重现性好、准确度高、分离效果好，均适用于该混配制剂中烯草酮和...     

苯并呋喃酮的高效液相色谱分析

采用高效液相色谱仪建立了测定苯并呋喃酮的定量定性分析方法.采用C18不锈钢柱(150 mm×4.6 mm i.d.,5μm)和二极管阵列检测器,乙腈、甲醇和0.1％磷酸水溶液为流动相,梯度洗脱,在268 nm波长下对苯并呋喃酮进行分离和定量分析.结果表明,该方法测得苯并呋喃酮的保留时间为10.1 min,线性相关系数为...     

气相色谱法测定乳康颗粒中乙酸辛酯的含量

建立乳康颗粒中乳香有效成分乙酸辛酯含量的检测方法.运用安捷伦色谱柱DB-WAX(30 mm×0.32 mm×0.50μm)和FID检测器(氢火焰离子化检测器),在检测器温度为300℃,气化室温度为290℃,色谱柱初始温度为50℃,维持1 min,以10℃/min的速率升至200℃,保持8 min,气体流量为氮气30.0...     

22%烟嘧·硝·氯吡OD高效液相色谱分析

建立了以乙腈和水(0.05%磷酸水溶液)为流动相,采用ZORBAX Eclipse Plus C_8(5μm)为填料的、250mm×4.6mm(i.d.)的不锈钢柱和UV检测器,在245nm检测波长下,对试样中的烟嘧磺隆、硝磺草酮、氯氟吡氧乙酸异辛酯进行高效液相色谱的分离和定量分析的方法。烟嘧磺隆、硝磺草酮及氯氟吡氧乙酸异辛酯标准偏差分别为0.07、0.06和0.05,变异系数分别为1.64%、0.58%和0.61%,平均回收率分别为99.52%、99.02%和99.16%。     

20%哒嗪·氰乳油毛细管气相色谱法分析

采用30m×0.25mm×0.25μmDB-5石英毛细管气相色谱柱与FID检测器,癸二酸二异辛酯为内标物,柱温270℃、进样口与检测器温度均为290℃,载气与尾吹氮气流速分别为1.3、30mL/min、氢气47mL/min及空气400mL/min,分流比为1∶20,在上述色谱条件下进行哒嗪硫磷与氰戊菊酯两种组分乳油定量分析。方法中哒嗪硫磷和氰戊菊酯变异系数分别为0.592%、1.378%,平均回收率为100.14%、99.69%,线性相关系数为0.9981和0.9970。     

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。