HPLC法测定注射用阿魏酸钠有关物质

建立了注射用阿魏酸钠有关物质的HPLC测定方法,色谱柱为C18柱(5μm,150 mm×4.6 mm),以0.1 mo1/L磷酸二氢钠-甲醇-乙腈(70∶10∶20)为流动相,流速为1.0 mL/min,检测波长为316 nm;最小检出量为0.05 ng.经验证该方法比《中国药典》所载该品测定方法专属性更强、准确、灵敏,适用于该制剂有关物质的测定.     

气相色谱法测定苹果中氟硅唑的残留量

[方法]研究了氟硅唑在苹果上的残留分析方法.样品用丙酮-水(体积比70:30)混合溶液提取,液液分配后,气相色谱-氮磷检测(NED)法测定.[结果]最小检出量为6.0×10-11 g,最低检测质量浓度为1.0×102mg/L,平均回收率为90.9%～104.7%,相对标准偏差为4.7%～8.8%.[结论]方法简便、快速、准确度高、精密度好.     

S-诱抗素的高效液相色谱分析

介绍了S-诱抗素的反相高效液相色谱定量分析方法.样品溶于甲醇中,采用二极管阵列检测器和250 mm×4mm(i.d.),5μC18手性柱;以苯甲酸甲酯为内标物;以甲醇-纯水(体积比60:40)作为流动相,检测波长为247nm.该方法平均回收率为99.66%.线性相关系数为0.9998,变异系数为4.12%,标准偏差为0.0044%.     

甲草胺在花生中的残留分析及其稳定性

研究了甲草胺在花生中的残留分析方法和甲草胺的稳定性.样品以丙酮-水(体积比4:1)振荡提取,石油醚液-液分配,中性氧化铝柱层析净化,气相色谱测定.结果表明:甲草胺最小检出量为3.0 × 10-11g,花生中最低检测质量分数为0.008 mg/kg,花生添加质量分数0.1～1.0 mg/kg,回收率为78.10%～85.59%,变异系数为0.64%～3.70%;冷藏(4℃)条件下甲草胺标准溶液可贮存10～20 d,甲草胺花生提取液可贮存10～20 d.     

噻虫嗪在土壤中的残留分析方法研究

建立了噻虫嗪在土壤中的残留分析方法。样品用甲醇提取,二氯甲烷萃取,液相色谱（SPD）测定。噻虫嗪的最低检出量：4×10-10g;最低检出浓度为0.01mg/kg。土壤添加回收率为86.3%～91.2%,相对标准偏差为2.8%～4.5%。结果表明,该方法符合农残分析要求。     

10％驱蚊酯驱蚊液中甲醇气相色谱分析方法研究

建立了测定10%驱蚊酯驱蚊液中甲醇杂质的气相色谱方法。采用气相色谱法,以去离子水为溶剂,使用30m×0.25mm×0.25μm INNOWAX毛细管柱和FID检测器,用气相色谱内标法对10%驱蚊酯驱蚊液中的甲醇进行分离和定量分析。结果表明,该分析方法的线性相关系数为0.9993,平均回收率为100.28%,标准偏差为0.000904,变异系数为0.7279%。     

固相萃取-高效液相色谱法测定藻液中甲磺隆的残留量

建立了固相萃取-高效液相色谱(SPE-HPLC)测定藻液中甲磺隆残留量的方法.实验确定了固相萃取方法,优化了萃取条件.高效液相色谱采用Eclipse XDB-C18(4.6 mm×150 mm,5μm)分离,以甲醇∶水(85∶15,体积比)为流动相,紫外检测波长为227 nm.该方法简便、快速、准确.实验结果表明甲磺隆具有良好的环境特性,将其用于治理"水华"、"赤潮"的急性爆发是可行的.     

超高效液相色谱-电喷雾串联质谱法测定戊唑醇、肟菌酯及代谢物肟菌酸在西瓜和土壤中的残留

[目的]建立同时测定西瓜和土壤中戊唑醇、肟菌酯及代谢物肟菌酸残留量的超高效液相色谱串联质谱法(UPLC-MS/MS)。[方法]样品中的待测农药组分采用乙腈-水(体积比4∶1)提取,硅藻土液液萃取小柱净化,采用UPLC-MS/MS法,ESI(+)电离方式,多反应监测(MRM)定量测定。[结果]仪器最低检测量为戊唑醇5.0×10-13g,肟菌酯4.0×10-13g,肟菌酸2.5×10-13g;3种农药的最低检出质量分数均为0.02 mg/kg,在西瓜和土壤中的添加回收率为81.8%～94.2%,变异系数为3.67%～7.04%。[结论]该方法快速、准确、灵敏度高,适合西瓜与土壤样品中戊唑醇、肟菌酯及肟菌酸的残留量测定。     

核壳型色谱柱-高效液相色谱法快速分离检测水飞蓟素中7种非对映异构体

采用核壳型色谱柱-高效液相色谱法快速分离检测水飞蓟素中7种非对映异构体,优化了液相色谱条件,实现了7种非对映异构体的快速完全分离,并应用于市售水飞蓟制剂的分离检测。优化色谱条件如下:核壳型Halo C_(18)色谱柱(150mm×4.6mm,2.7μm)、甲醇-水-甲酸(30∶70∶0.1)-甲醇为流动相、梯度洗脱、流速0.35mL·min~(-1)、进样量2μL。该方法在0.01~0.1mg·mL~(-1)浓度范围内线性关系良好(R20.997),色谱峰峰面积和保留时间的相对标准偏差(RSD)分别为1.74%和0.67%(n=6)。该方法操作简单、省时、分离度好,可用于水飞蓟制剂的分析检测,也为水飞蓟素中非对映异构体的分离检测提供新的思路。     

甘蓝中吡蚜酮残留量的高效液相色谱分析

建立了吡蚜酮在甘蓝中的残留分析方法.样品经乙腈和二氯甲烷提取、柱层析净化后,进行高效液相色谱检测.最小检出量为1.0×10-10g,最低检出质量分数为0.005mg/kg,样品平均添加回收率为90.62%～95.09%.该方法简便快捷,符合农药残留检测要求.     

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。