反相高效液相色谱法测定化妆品中的3-O-乙基维生素

采用反相高效液相色谱法测定化妆品中的3-O-乙基维生素C,色谱条件:SH IMADZU Sh im-pack VP-C18ODS(150 mm×4.6 mm,5μm)色谱柱;C18ODS保护柱芯;流动相V(甲醇)∶V(0.025 mol/L KH2PO4)=20∶80;流速:1.0 mL/m in;柱温:30℃;紫外检测器检测,检测池温度:40℃,波长:254 nm。结果表明,在此条件下,3-O-乙基维生素C在0~100 mg/L与相应的峰面积具有良好的线性关系(r=0.999 2),线性回归方程为A=31.170 3,ρ回收率在97.75%~100.60%,方法精密度RSD约为2.6%(n=5)。     

高效液相色谱法测定环境空气中甲醛含量质量控制

建立用2,4-二硝基苯肼(DNPH)吸收、高效液相色谱法快速测定环境空气中甲醛含量的的实验室室内质量控制体系。采用Kromasil 100-5C18色谱柱(4.6mm×250mm×5μm),V(甲醇)∶V(乙腈)∶V(水)=75∶10∶15为流动相,流量1.0 m L/min,检测器波长360nm,柱温25℃。被测样品浓度在0.05~0.60μg/m L范围内分离效果良好,其峰面积与质量浓度线性相关系数为0.9997,回收率好,相对标准偏差小于1.00%。结果表明,该方法操作快速简便、精密度高,重现性和准确度良好,可适用于环境空气中甲醛含量的测定方法。     

高效液相色谱法测定泰拉菌素含量的方法研究

利用高效液相色谱法测定泰拉菌素的含量,采用YMC Pack Pro C18(150 mm×4.6 mm,3μm)色谱柱,流动相为V(甲醇)∶V(乙腈)∶V(50 mmol/L pH=8磷酸缓冲溶液)=45∶25∶30,流速为2.0 mL/min;检测波长为210 nm;柱温为35℃;进样量为20μL。泰拉菌素质量浓度在10~100 mg/L范围内具有良好的线性关系,r=0.999 7。该方法简便、准确,灵敏度高,重现性好,可用于测定泰拉菌素的含量。     

固相萃取-高效液相色谱法检测鱼粉中三聚氰胺

建立了鱼粉中三聚氰胺的固相萃取-高效液相色谱分析方法。色谱柱为Waters symmetry C18柱(4.6mm×150mm,5μm),柱温35℃;流动相为0.01mol/L庚烷磺酸钠-0.01mol/L柠檬酸(pH=3.0)缓冲液∶乙腈混合溶液(92∶8,V∶V);检测波长为240nm,流速1.0mL/min,进样量20μL,保留时间约7.313min。此条件下三聚氰胺在0.2～10mg/L范围内具有良好的线性关系,添加回收率为86.3%～100.1%,RSD小于5.0%。     

环丙氟虫胺原药高效液相色谱分析

研究了高效液相色谱测定环丙氟虫胺原药含量的HPLC方法.采用C18不锈钢色谱柱(150 mm×4.6 mm i.d.×5μm)和紫外检测器,以甲醇-0.1％磷酸水溶液(V∶V=75∶25)为流动相,流速为1.5 mL/min,在240 nm波长下,柱温为40C±2℃,进样体积为10μL.在上述色谱操作条件下,对环丙氟虫胺原药进行了定量分析.考察了分析方法特异性、线性回归方程、精密度和准确度.该方法测得环丙氟虫胺的保留时间约8.6 min,线性相关系数为0.9998,标准偏差0.10,变异系数0.10％,平均回收率99.20％.     

2-乙基蒽酮同分异构体的分离方法研究

建立了能分离出2-乙基-9-蒽酮单体的柱层析法和能完全分开2-乙基蒽酮同分异构体的正相液相色谱法。实验研究表明,在展开剂V(正己烷)∶V(二氯甲烷)∶V(乙酸乙酯)=80∶15∶0.2时,通过柱层析法可以分离得到2-乙基-9-蒽酮单体。利用重结晶法可结晶得到2-乙基-10-蒽酮单体,其纯度达98.96%。采用Agilent ZORBAX SIL(5μm,4.6 mm×250 mm)硅胶色谱柱,柱温为30℃,体积比为80∶19.5∶0.5的正己烷-二氯甲烷-乙酸乙酯为流动相,流速为1 mL/min,紫外检测波长为230 nm的色谱条件时,能完全分开2-乙基蒽酮的两种同分异构体。以实验分离得到的2-乙基-10-蒽酮单体做标样,能准确定量双氧水工作液中2-乙基蒽酮的含量。     

高效液相色谱法测定胡麻卵磷脂中磷脂酰肌醇含量

建立高效液相色谱法测定胡麻卵磷脂中磷脂酰肌醇的方法。使用Agilent 1200高效液相色谱仪和C18色谱柱(5μm,150mm×4.6mm),以V(甲醇)∶V(异丙醇)∶V(乙腈)=37∶61∶2为流动相,检测波长为206nm;流速:1.0m L/min;柱温:35℃。定量进样,进样量10μL,以峰面积定量。结果表明:胡麻卵磷脂中磷脂酰肌醇在5.015~25.045μg/m L浓度范围内线性较好,测定出胡麻卵磷脂中磷脂酰肌醇占5.394%,平均回收率98.58%。该方法可信度较高、分析速度快、操作简便,可为检定胡麻中磷脂酰肌醇含量提供科学参考。     

高效液相色谱法测定工业废水中盐酸苯肼

通过实验建立了工业废水中盐酸苯肼的高效液相色谱分析方法。色谱条件为:Kromasil-C18(150 mm×4.6 mm,5μm)色谱柱,流速1 mL/min,柱温30℃,进样体积10μL,流动相为V(甲醇)∶V(8 mmol/L KH2PO4+4 mmol/LK2HPO4)=35∶65,测定波长235 nm。测定结果表明,线性范围为0.1～100 mg/L,平均加标回收率为98.2%,相对标准偏差为1.06%。该方法操作简单,分析快速、准确。     

UPLC法检测HNHHJ-1菌株发酵液中2-羟基联苯含量

采用超高效液相色谱法(UPLC)测定脱硫菌发酵液中2-羟基联苯(2-HBP)的含量。色谱柱为ACQVITY DPLC@BEH C18(2.1×50mm,1.7μm,Waters),流动相为甲醇∶水(90∶10,V/V),柱温30℃,流速0.2m L/min,进样量2μL,PDA检测器检测2-HBP,检测器检出限范围为0~200mg/L。结果显示2-HBP的保留时间为0.74min。利用该检测方法得到HNHHJ-1菌株培养后的发酵液中2-HBP的含量为5.35mg/L。     

二氯甲烷中有关物质的检测方法及方法确认

阐述一种以Agilent DB-624(30m×0.32mm×1.8μm)为色谱柱,FID为检测器,进样量为2μL,流速1.0mL/min,分流比为1∶40的气相色谱方法,以测定二氯甲烷中乙醇、2-甲基-2-丁烯及挥发性杂质。以Agilent HP-1(30m×0.32mm×1.0μm)为色谱柱,FID为检测器,进样量为2μL,流速1.0mL/min,分流比为1∶40的气相色谱方法检测二氯甲烷中的环戊烯,并分别进行了方法确认。     

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。