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目的:建立HPLC-ELSD法测定银杏内酯B脂微球中溶血磷脂酰胆碱的含量。方法:采用硅胶色谱柱(Platisil Silica,250mm×4.6mm,5μm),流动相为甲醇-冰醋酸(500∶10,三乙胺调节pH值至6.0),流速为1.0mL·min~(-1),柱温为40℃,检测器为蒸发光散射检测器。结果:溶血磷脂酰胆碱在38.4~480μg·mL~(-1)时,线性关系良好(r=0.9987),平均回收率(n=9)为102.13%,RSD为3.46%。结论:该方法准确,重现性好,可用于银杏内酯B脂微球中溶血磷脂酰胆碱的含量测定。 相似文献
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蛋黄卵磷脂中鞘磷脂的分离与结构鉴定 总被引:1,自引:0,他引:1
目的:通过柱层析与高效液相色谱方法对蛋黄卵磷脂中的鞘磷脂进行制备分离,采用ESI质谱、GC-MS、核磁共振方法对鞘磷脂进行结构鉴定。结论:从蛋黄卵磷脂中分离鉴定了5种鞘磷脂,分别是N-棕榈酰-3-磷酸胆碱酰鞘氨醇、N-亚油酰-3-磷酸胆碱酰鞘氨醇、N-油酰-3-磷酸胆碱酰鞘氨醇、N-硬脂酰-3-磷酸胆碱酰鞘氨醇以及N-花生四烯酰-3-磷酸胆碱酰鞘氨醇。蛋黄卵磷脂中鞘磷脂成分的全面分析为蛋黄卵磷脂的产品质量研究以及鞘磷脂在医药方面的药理研究与应用等方面提供物质结构参考。 相似文献
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一、天然卵磷脂及在美容中的应用
组成生物的大分子主要有四类:核酸、蛋白质、多糖和脂类,比较而言,前三者在化妆品上都产生过热点,而脂类多作为膏霜中的油类。卵磷脂属于脂类,卵磷脂泛指含有磷脂质的产品,其主要成分为磷脂酰胆碱、磷脂酰乙醇胺、磷脂酸、磷脂酰肌醇等,其中丙酮不溶物大于50%,存在于各种动植物中。 相似文献
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张平 《精细与专用化学品》1992,(12):1-5
一、概况卵磷脂又称大豆磷脂,天然存在于蛋黄、菜籽、大豆、向日葵籽、某些谷物中,另外在动物和人类大脑中也有少量存在。卵磷脂于19世纪首先在蛋黄中被发现。但实际具备商业用途的是大豆中所含的卵磷脂,在食品中应用已有60多年历史。大豆磷脂是由一些具有表面活性的物质组成的混合物。其主要成分是,磷脂酰胆碱(PC,也称卵磷脂)、磷脂酰乙醇胺(PE,也称脑磷脂)、磷脂酸(PA)和磷脂酰肌醇(PI)等。结构式如图1所示。 相似文献
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张平 《精细与专用化学品》1993,(8)
美国卵磷脂市场较为稳定,桶装产品价格为32~36美分/lb,大罐散装产品为26~28美分/lb。对卵磷脂的需求(主要用于化妆品和巧克力)也较为稳定。一些工业界人士认为专用卵磷脂市场——精制卵磷脂将充满活力。所谓精制卵磷脂是指用乙醇萃取法从卵磷脂中分离出的磷脂。磷脂酰胆碱是卵磷脂中含 相似文献
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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。 相似文献
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M. S. J. Simmonds W. M. Blaney F. Delle Monache M. Marquina Mac-Quhae G. B. Marini Bettolo 《Journal of chemical ecology》1985,11(12):1593-1599
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. 相似文献
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Cheng-Le Zhao Shane Porzio Alan Smith Haiyan Ge H. T. Davis L. E. Scriven 《Journal of Coatings Technology and Research》2006,3(2):109-115
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. 相似文献
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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. 相似文献
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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. 相似文献
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中蓝晨光化工研究院有限公司《塑料工业》编辑部 《塑料工业》2009,37(3)
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. 相似文献
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中蓝晨光化工研究院《塑料工业》编辑部 《塑料工业》2007,35(3):1-25,67
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。 相似文献