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HPLC法测定金银花茶电绿原酸含量研究 总被引:1,自引:0,他引:1
目的:建立金银花茶中绿原酸含量的测定方法。方法:色谱柱:Kromasil C18柱(250mm×416mm,5um);流动相:乙腈-水-磷酸(13:87:0.4)流速:1.0mL·min^-1.检测波长:327nm;柱温:30℃。结果:绿原酸在8.8—44.0μg·mL^-1范围内线性关系良好,线性回归方程为Y=0.9... 相似文献
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RP-HPLC法测定落叶松中二氢槲皮素的含量 总被引:1,自引:0,他引:1
采用反相高效液相色谱法测定落叶松中二氢槲皮素的含量。确定色谱条件为:色谱柱Hypersil ODS—C18(4.6mm×200mm,5μm);流动相为V(甲酵):V(水):V(冰醋酸)=40:59:1;流速为1.0mL·min^-1;检测波长为288nm;柱温为28℃。在此条件下,二氢槲皮素与其它组分得到良好的分离。线性范围为0.02~0.2μg·μL^-1(r=0.9998),精密度RSD为0.96%(n=5),平均回收率为100.4%。 相似文献
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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:SHIMADZU Shim-pack VP-C18ODS(150mm×4.6mm,5μm)色谱柱;C18ODS保护柱芯;流动相V(甲醇):V(0.025mol/L KH2PO4)=20:80;流速:1.0mL/min;柱温:30℃;紫外检测器检测,检测池温度:40℃,波长:254nm。结果表明,在此条件下,3—O-乙基维生素C在0-100mg/L与相应的峰面积具有良好的线性关系(r=0.9992),线性回归方程为A=31.1703ρ,回收率在97.75%-100.60%,方法精密度RSD约为2.6%(n=5)。 相似文献
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目的:测定氟康唑的含量;方法:采用HPLC法。色谱柱为Kromasil C18(4.6mm×250mm,5μm)、流动相为pH7.0磷酸盐缓冲液一甲醇(54:45)、检测波长260hm、柱温为室温,结果氟康唑(r=0.9998)在100-300μg/ml范围内线性关系良好,平均回收率为100.15%;结论:所建立的测定方法操作简便、准确、重现性良好。 相似文献
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以槲皮素、山奈素和异鼠李素为指标,建立HPLC法测定牙膏中银杏叶提取物总黄酮苷的含量。采用Agilent ZORBAX Eclipse XDB-C18色谱柱(Analytical 4.6×250mm 5-Micron);流动相为甲醇-0.4%磷酸(55/45,V/V);流速为1.0mL/min;检测波长为360nm;柱温为40℃;进样量为20μL。结果表明,槲皮素、山奈素和异鼠李素浓度分别在2.1~21.0、1.8~18.0和0.42~4.2μg/mL范围内呈良好的线性关系,相关系数分别为:0.9999、0.9999和0.9998;槲皮素、山奈素和异鼠李素回收率分别为:97.7%、98.3%和97.6%。该方法简单、灵敏、准确,可用于牙膏中银杏叶提取物总黄酮苷含量的测定。 相似文献
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建立妇科止血灵胶囊高效液相色谱法测定芍药苷的方法。色谱柱:DiamonsilCl8(4.6mm×250mm,5μm)。流动相:乙腈-0.1%磷酸溶液(14:86)。流速:1.0mL·min-1。检测波长:230nm。柱温:35℃。进样量:10μg。芍药苷在12.6-252.0μg/mL范围内呈良好线性关系,r=0.9997。平均加样回收率为98.37%,RSD=1.34%(n=5)。所建立的方法简便准确、灵敏度高,可作为妇科止血灵胶囊的质量控制方法。 相似文献
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建立了用高效液相色谱测定水体中6种苯甲酰脲类杀虫剂(除虫脲、灭幼脲、杀铃脲、氟铃腺、虱螨脲和氟苯脲)残留量的方法.水样采用液液萃取,以二氯甲烷为提取剂.色谱分析条件:Kromasil-100—5C18色谱柱(250mm×4.6mm,粒径5μm),流动相V(甲醇):V(水)=80:20,流速为1.0ml/Mmin,柱温为室温,紫外检测波长为260nm.杀虫剂的质量浓度在1.0~2μg/mL范围内与色谱峰面积的线性关系良好,相关系数R^2=0.9974~1.0000,检测限为0.09~0.26μg/mL.在蒸馏水和湖水中,6种杀虫剂3个添加浓度水平的平均回收率分别为79.62%~95.28%和75.03%~98.06%,相对标准偏差分别为0.94%~11.04%和0.60%~12.56%.该方法可用于环境水样中苯甲酰脲类杀虫剂的残留量检测分析. 相似文献
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建立RP-HPLC法测定注射用丹参酮ⅡA磺酸钠中丹参酮ⅡA磺酸钠的含量。采用德国Century SIL BDS C18柱(4.6mm×200mm,5μm),以甲醇-乙腈-水-三乙胺(体积比为55:5:40:0.3,磷酸调pH值为8.O~9.0)为流动相,流速为1.0mL/min,检测波长271nm;柱温为室温。结果显示,丹参酮ⅡA磺酸钠在25.4-254μg/mL内浓度与峰面积呈良好线性关系,r=0.9998,日内、日间精密度分别为1.38%、1.24%,平均回收率为99.3%,RSD=0.43%。该方法快速、准确,可用于注射用丹参酮ⅡA磺酸钠中丹参酮ⅡA磺酸钠的含量测定。 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