高效液相色谱法测定塑料制品中五种荧光增白剂

建立了同时测定塑料制品中五种荧光增白剂的高效液相色谱法。样品用20 m L三氯甲烷在30℃的条件下超声萃取40 min,滤纸过滤,再用20 m L三氯甲烷超声提取一次,过滤,最后用10 m L三氯甲烷超声提取一次,合并提取液用三氯甲烷定容至50 m L,供液相色谱仪测试。采用苯基柱(150 mm×4.6 mm,3μm)为分析柱,以甲醇和水为流动相,荧光激发波长为365 nm,发射波长为430 nm。结果显示,5种荧光增白剂可以较好地分离,方法的检出限为0.025~0.050 mg/kg之间。五种荧光增白剂的回收率在87.3%~103.5%之间,相对标准偏差在2.5%~6.3%之间。此方法可以快速、有效的检测塑料制品中荧光物质的含量。     

高效液相色谱-荧光法测定一次性纸杯和餐盒中3种荧光增白剂的含量

建立测定一次性纸杯和餐盒中荧光增白剂含量的高效液相色谱-荧光方法。采用Inertsil ODS-3(250 mm×4.6 mm,5μm)为分析柱,以5 mmol/L乙酸铵溶液和乙腈为流动相,梯度洗脱,流速为0.5 m L/min,荧光激发波长为350 nm,发射波长为430 nm。结果表明,所选用的3种荧光增白剂(B2729、220、B2730)可以较好地被分离,回收率为77.4%⁹4.6%,相对标准偏差<10%且线性关系良好。该法简便快捷、结果准确、灵敏度高,能够满足对一次性纸杯和餐盒中荧光增白剂含量的检测。     

高效液相色谱-荧光法测定一次性纸杯和餐盒中3种荧光增白剂的含量

建立测定一次性纸杯和餐盒中荧光增白剂含量的高效液相色谱-荧光方法。采用Inertsil ODS-3(250 mm×4.6 mm,5μm)为分析柱,以5 mmol/L乙酸铵溶液和乙腈为流动相,梯度洗脱,流速为0.5 m L/min,荧光激发波长为350 nm,发射波长为430 nm。结果表明,所选用的3种荧光增白剂(B2729、220、B2730)可以较好地被分离,回收率为77.4%~94.6%,相对标准偏差10%且线性关系良好。该法简便快捷、结果准确、灵敏度高,能够满足对一次性纸杯和餐盒中荧光增白剂含量的检测。     

高效液相色谱法检测化妆品中4种荧光增白剂及其荧光快筛和质谱确证

建立了通过荧光快筛、高效液相色谱检测和质谱联用确证测定化妆品中4种荧光增白剂的方法。样品经荧光快筛,疑似品经乙腈溶液超声提取,以梯度洗脱和C18色谱柱分离,DAD检测器检测计算荧光增白剂28号、71号、85号和351号含量,阳性品用HPLC-MS/MS确证。在5~100μg/m L与1~20μg/m L范围内样品中荧光增白剂质量浓度与350 nm紫外光吸收强度呈良好线性关系,相关系数大于0.999,方法对荧光增白剂28号、71号、85号的检出和定量下限分别为10 ng和25 ng,对荧光增白剂351号的检出和定量下限分别为2 ng和5 ng,回收率91.7%~124.5%,相对标准偏差为0.7%~10.0%。该方法适于快速、高效、准确测定大批化妆品中4种荧光增白剂含量。     

卫生用纺织品中荧光增白剂的测定-高效液相色谱法

本文主要通过研究色谱条件、萃取条件、方法的检测下限、回收率、重复性等内容,确定了利用高效液相色谱-二极管阵列检测器法测定纺织品中5种荧光增白剂(C.I.荧光增白剂71、85、199∶1、351、393)含量的最佳测试方法,即:检测波长为360 nm,由乙腈和乙酸铵溶液为流动相梯度洗脱,萃取溶剂为水+N,N-二甲基甲酰胺(DMF)(40+60),萃取溶剂体积为25 m L,超声萃取时间为30 min,萃取温度为60℃,5种荧光增白剂在0.1~50 mg/L浓度范围内的线性相关系数r为0.999 3~0.999 9,检测低限为0.5~2.5 mg/kg,不同添加水平时,回收率为83.5%~102.8%,相对标准偏差为2.1%~5.4%。该方法具有简便、快速、准确的优点,适用于纺织品中荧光增白剂的检测。     

高效液相色谱法测定土壤中丙烯酰胺的含量

建立高效液相色谱法测定土壤中丙烯酰胺的含量,样品经超声提取、离心、过滤等步骤,经ZORBAX Eclipse Plus C18色谱柱(4.6×100 mm,3.5μm)分离; V(甲醇)∶V(水)=5∶95为流动相,DAD检测器波长210 nm。方法在0.05～5.0μg/m L范围内与色谱峰面积线性关系良好,相关系数(r)不小于0.999。土壤中丙烯酰胺的检出限为0.02 mg/kg,加标回收率在77.1%～99.5%之间,测定结果的相对标准偏差均小于10%(n=6)。该方法适用于土壤中丙烯酰胺含量的检测。     

高效液相色谱法测定辣木叶中的维生素A

建立了测定辣木叶中维生素A的高效液相色谱法。样品经过皂化提取后采用石油醚萃取,采用C18柱(4.6mm×250mm,5μm)进行分离检测,流动相为甲醇/水=95/5,流速1.0mL/min,荧光检测器:激发波长325 nm,发射波长485 nm,外标法定量。结果表明:维生素A在1.0~25.0mg/L范围内线性良好,相关系数为0.9998,回收率为87%~102%,RSD为3.04%,检出限为0.02mg/kg。该方法准确可靠、灵敏度高,能够满足实际样品检测需要。     

高效液相色谱法测定化妆品中氨甲环酸的含量

建立了测定化妆品中氨甲环酸含量的高效液相色谱法。采用Zorbax SB C_(18)色谱柱(250 mm×4.6 mm,5μm)分离,以水-甲醇-18.3 g/L磷酸二氢钠溶液(含体积分数1.26%的三乙胺,pH=2.5)为流动相进行梯度洗脱,流速0.8 m L/min,柱温25℃,进样量10μL,样品经体积比为1∶1的甲醇-饱和氯化钠溶液提取,用二极管阵列检测器(DAD)检测,检测波长220 nm,外标法定量。结果表明,氨甲环酸在100~4 000 mg/L范围内线性关系良好,相关系数R~2=0.999 9。方法的检出限为7 mg/L,定量限为22 mg/L。样品的平均加标回收率为94.0%~102.5%,相对标准偏差为0.57%~2.69%(n=3)。该方法前处理简单、回收率高、精密度好,适用于化妆品中氨甲环酸含量的测定。     

动物源食品中同时检测磺胺类、沙星类药物残留量的方法——高效液相色谱法的研究

研究了高效液相色谱法紫外检测器同时测定动物源食品鸡肉中7种磺胺类药物和4种沙星类药物含量的方法,采用色谱柱为C18(atlantis),4.6mm×250mm×5μm,流动相为磷酸溶液—乙腈(85+15,v/v),紫外检测波长为270nm,流速1.0m L/min,进样量50μL,7种磺胺类药物和4种沙星类药物在0.1~0.4mg/L范围内具有良好的线性关系,在添加浓度为0.08mg/kg、0.12 mg/kg、0.16 mg/kg时,7种磺胺类药物和4种沙星类药物的回收率80%左右,RSD小于5%。本方法操作简单、快速、精密度高、线性范围宽,适用于鸡肉中7种磺胺类药物和4种沙星类药物的同时测定。     

辛酰羟肟酸含量测定方法

采用高效液相色谱-二极管阵列检测器测定辛酰羟肟酸的含量。使用ZORBAX SB-C18色谱柱(4.6mm×250mm,5μm),以乙腈-水(55:45)(体积比)为流动相,流速1.0mL/min,柱温30℃,检测波长为218nm,参比波长为360nm。辛酰羟肟酸在112.0～1574.0mg/L的范围内具有良好的线性,相关系数R~2=0.9992。本方法的加标回收率为96.73%～101.39%,相对标准偏差RSD5%(n=6)。     

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。