高效液相色谱-串联质谱法测定猪肝中5种α2受体激动剂

高效液相色谱-串联质谱测定猪肝中5种α2受体激动剂残留量。样品加入碳酸钠缓冲液,乙酸乙酯提取,MCX固相萃取净化后用甲酸-乙腈溶解,高效液相色谱-串联质谱测定。结果显示,5种α2受体激动剂在0～20μg/L浓度范围内线性良好,相关系数(r)均大于0.995;在0.5～4.5μg/kg添加水平下,5种α2受体激动剂回收率为70%～120%,相对标准偏差(RSD)均小于10%;本方法对猪肝中5种α2受体激动剂的检出限为0.5μg/kg。     

磁性固相萃取-高效液相色谱串联三重四级杆质谱法测定环境水样中的磺胺类抗生素残留

建立了磁性固相萃取-高效液相色谱串联三重四级杆质谱法分析环境水样中的磺胺类抗生素残留的方法。优化后的磁性固相萃取条件:将50 mg磁性萃取材料加入100 m L水样,调节水样pH至4,振荡萃取20 min后利用外加磁场收集磁性萃取材料,再用4 m L甲醇(含1%氨水)涡旋洗脱,分离洗脱液氮吹至干,用液相色谱初始流动相定容后进行高效液相色谱-串联质谱分析。4种磺胺类抗生素在5~500μg/L范围内线性良好,相关系数均大于0.999,检出限为4.2~4.7μg/L,加标回收率为72.3%~88.5%,相对标准偏差在3.5%~10.2%之间。该方法简单便捷、用时短、重现性好、有机试剂消耗少,能够应用于实际水样中磺胺类抗生素的检测。     

新型基质固相分散萃取净化-高效液相色谱荧光检测法测定香精香料中的黄曲霉毒素B1、B2、G1和G2

建立了一种新型基质固相分散萃取净化技术结合高效液相色谱-荧光检测法(HPLC-FLR)测定香精香料中的4种黄曲霉毒素(B1、B2、G1、G2)的方法。该前处理装置结合基质分散萃取和柱层析对样品进行在线萃取、净化和衍生化,之后对样品浓缩并利用LC-FLR分析测定。色谱方法以水(体积分数65%)和乙腈(体积分数35%)为流动相,0.2 mL/min流速下梯度洗脱,采用C_(18)色谱柱进行液相色谱分离,荧光光度法测定(激发波长360 nm,发射波长440 nm)。结果表明,该方法的前处理集净化萃取浓缩和衍生化为一体,操作方便且稳定性强,溶剂可回收;4个目标物质在0.5~120μg/L范围内具有较好的线性,各待测物的线性相关系数均大于0.999,检出限为0.15~0.35μg/L;对实际样品进行不同浓度的添加,平均回收率为76%~93%,日内精密度和日间精密度均5%,结果较为理想。该方法能较好地应用于香精香料实际样品中4种黄曲霉毒素的测定。     

SPE-UPLC-Q-TOF/MS测定水环境中的雌激素

研究建立了固相萃取、超高效液相色谱-四极杆串联飞行时间质谱(UPLC-Q-TOF/MS)测定水环境中6种雌激素(雌三醇、雌二醇、炔雌醇、雌酮、己烯雌酚、双酚A)的分析方法。水样经甲醇活化后的C18固相萃取小柱富集浓缩,用10 mL 10%的甲醇溶液淋洗,10 mL纯甲醇洗脱,洗脱液经高纯氮气吹至0.4 mL后用UPLC-Q-TOF/MS测定。6种常见的雌激素质量浓度在0.5~100μg/L范围内时,具有良好的线性(R0.993 7),检出限介于5.60~10.6 ng/L之间。空白加标水样为1μg/L的水平下,相对标准偏差(RSD)为2.8%~9.0%,其加标回收率为75%~101%。该方法可用于水体中雌激素的分析测定。     

固相萃取-气相色谱-质谱法同时测定化妆品中多环芳烃和邻苯二甲酸酯类物质

建立了固相萃取(SPE)-GC-MS法同时测定化妆品中的16种多环芳烃(PAHs)和17种邻苯二甲酸酯类(PAEs)的分析方法。样品经乙腈超声萃取后,经PSA/Slica玻璃柱净化,以Agilent Select PAH色谱柱分离,气相色谱-质谱法选择离子(SIM)监测测定。16种PAHs和17种PAEs在0.5~200μg/L范围内线性良好,相关系数均大于0.99;PAHs方法检出限为0.6~1.0μg/kg,方法定量限为1.9~3.3μg/kg,阴性样品3个添加水平的平均回收率为86.4%~112.2%;PAEs方法检出限为0.4~2.3μg/kg,方法定量限为1.5~7.6μg/kg,阴性样品3个添加水平的平均回收率为82.2%~114.1%;相对标准偏差均小于10%(n=6)。     

SPE-UPLC-MS/MS同时测定食品中二甲基黄、二乙基黄

建立固相萃取-超高效液相色谱-串联质谱/质谱法(SPE-HPLC-MS/MS)测定食品中二甲基黄、二乙基黄的分析方法。试样经乙腈提取,C18固相萃取柱净化后,以乙腈和0.1%甲酸水溶液(v/v)为流动相,C18色谱柱分离,采用电喷雾离子源,正离子扫描多反应监测(MRM)模式进行检测。二甲基黄和二乙基黄在0.1~50μg/L浓度范围内均呈良好线性关系,相关系数(r2)均大于0.999。加标回收率为79.8%~86.8%,相对标准偏差为7.4%~10.8%。二甲基黄、二乙基黄的方法检出限均为0.5μg/kg;定量限均为2μg/kg。方法简单快速、准确、灵敏,适用于食品中二甲基黄、二乙基黄的测定。     

水厂水处理各工艺段水中阿特拉津的检测与评价

以沈阳市某水厂水处理工艺单元特征污染物阿特拉津为研究对象,建立了固相萃取-超高液相色谱-串联质谱法(SPE-UPLC-MS/MS)测定水中阿特拉津的分析方法,水样经全自动固相萃取仪富集后,用超高液相色谱-串联三重四极杆质谱检测仪进行分析检测。阿特拉津标准线性良好,线性范围在0.0 178~1.78μg/L,相关系数为0.998 7,加标回收率大于70%,相对标准偏差小于5%(n=6),方法测定下限为0.017μg/L。利用该方法对水厂原水及处理工艺流程中各工艺段水进行检测,阿特拉津虽不同程度被检出,但其浓度远低于《地表水环境质量标准》(GB 3838—2002)和《生活饮用水卫生标准》(GB 5749—2006)限值。     

UPLC-ESI-MS/MS检测废水中11种全氟化合物

建立了固相萃取、超高效液相色谱-电喷雾串联三重四极杆质谱(UPLC-ESI-MS/MS)同时测定废水中11种全氟化合物监测方法。结果表明,11种全氟化合物在0.10~150μg/L浓度范围内线性关系良好,方法检出限为0.1~0.4 ng/L,加标回收率为66.8%~108.1%,相对标准偏差RSD20%。     

高效液相色谱法测定乳粉和鸡肉中5种性激素

建立液液萃取(LLE)-固相萃取(SPE)-高效液相色谱(HPLC/DAD)方法对乳粉和鸡肉中5种性激素进行测定。实验采用LLE和SPE联合技术对复杂基质样品进行净化处理,优化了萃取过程中溶剂及固相萃取小柱种类。同时,采用反相C18色谱柱,梯度洗脱方式进行色谱定性、定量分析。结果表明,目标分析物在1.0～200.0μg/mL范围内有良好的线性相关性,方法检出限4.7～21.0μg/kg,方法回收率88.8%～104.2%,相对标准偏差<7.2%。应用该方法对市质检所送检的10批次乳粉和鸡肉样品进行分析,5种性激素均未检出。该方法灵敏、可靠,显示出其富集与分离实际食品样品中多种性激素的良好应用前景。     

固相萃取-超高效液相色谱-串联质谱法测定祛痘化妆品中4种林可胺类化合物

采用固相萃取净化技术和超高效液相色谱-串联质谱方法(UPLC-MS/MS),建立了测定祛痘化妆品中4种林可胺类化合物(林可霉素、克林霉素、克林霉素磷酸酯和吡利霉素)的分析方法。样品用酸化乙腈提取,阳离子交换固相萃取小柱(MCX)净化,以乙腈-10mmoL/L乙酸铵溶液(pH 3.0)为流动相,经C18色谱柱梯度洗脱分离,电喷雾正离子模式电离,多反应监测模式检测,外标法定量。结果表明,4种林可胺类化合物的方法定量限(LOQs)均为10μg/kg;在5~200μg/L范围内线性关系良好,相关系数均大于0.999 0;在祛痘膏、祛痘水样品中进行10、100、1 000μg/kg 3个添加水平试验,平均回收率范围为87%~105%,相对标准偏差(n=6)在3.3%~10.2%之间。采用此方法测定了祛痘化妆品中林可胺类化合物的含量水平,发现存在违规添加现象。     

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。