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1.
分别研究了X-5和AB-8两种不同树脂对桃金娘叶总黄酮的静态吸附和解吸性能。结果表明,X-5树脂具有较好的吸附和解吸参数,是一种分离纯化桃金娘叶总黄酮较好的树脂,其最佳条件为温度为25℃、吸附时间为6 h、黄酮原液pH=6时,吸附率最大,为66.07%,此时选用95%的乙醇做解吸剂,于30℃温度下解吸12 h时,解吸效果最佳。  相似文献   

2.
依据东北岩高兰总黄酮的吸附和解吸能力,采用静态吸附和解吸实验对8种型号的大孔吸附树脂进行筛选。结果显示,AB-8型大孔吸附树脂对东北岩高兰总黄酮具有较好的吸附和解吸性能。经HPLC分析提取出的东北岩高兰主要有5种成分。进一步探究了总黄酮的纯化工艺,得到5种成分的最佳静态吸附解吸条件为:吸附平衡时间1.0 h,解吸溶剂为体积分数95%的乙醇,解吸平衡时间1.5 h。不同温度(25、30、35℃)下,AB-8型大孔吸附树脂对东北岩高兰不同成分的吸附等温线均符合Freundlich模型和Langmuir模型。5种成分的最佳动态吸附洗脱工艺条件为:上样液质量浓度为5 g/L,最大上样量400 mL,5倍柱体积(BV)的体积分数为20%的乙醇洗脱杂质,5倍BV的体积分数为95%的乙醇洗脱成分,洗脱流速3m L/min。在最佳实验条件下,东北岩高兰总黄酮的质量分数由纯化前的49.16%提高到纯化后的89.59%,表明AB-8型大孔吸附树脂能够有效纯化东北岩高兰。  相似文献   

3.
以栾树叶多酚提取物为原料,比较了7种大孔树脂对栾树叶多酚的静态吸附与解吸效果,结果表明AB-8树脂性能最佳,其24h静态吸附量为13.74mg/g,解吸率为98.35%,3h内达到吸附平衡与解吸平衡。AB-8树脂动态吸附较佳条件为上样液质量浓度为4g/L,上样液pH值为6,在此条件下吸附率为88.21%,动态洗脱较佳条件为洗脱剂乙醇体积分数为60%,洗脱速度为1mL/min,解吸率达到89.91%,在该条件下栾树叶总多酚经AB-8树脂纯化后,质量分数由50.36%增加到72.37%,回收率为86.83%。  相似文献   

4.
大孔树脂吸附纯化葡萄籽原花青素的研究   总被引:1,自引:0,他引:1  
采用大孔树脂对葡萄籽原花青素进行吸附纯化,以吸附率和解吸率及纯化效果为指标,比较了7种大孔树脂对原花青素的吸附解吸性能。研究了上样量、洗脱剂浓度、上样流速、洗脱剂用量对原花青素纯化效果的影响。结果表明,AB-8大孔树脂对葡萄籽中原花青素的吸附效果最好,树脂体积为20 mL,上样量为80 mL,上样流速为40 mL/h,用40%的乙醇洗脱,洗脱剂用量为100 mL,洗脱流速为80 mL/h时的纯化效果最好,该条件下原花青素洗脱率为94.37%,所得溶质纯度可达89.63%。  相似文献   

5.
以总黄酮的吸附量、回收率及解吸率为考察指标,研究了大孔吸附树脂分离纯化追风伞总黄酮的工艺条件。通过静态吸附实验比较了7种不同类型大孔吸附树脂的吸附特性,确定了D101型大孔吸附树脂用于追风伞总黄酮的纯化富集。通过动态吸附实验,确定了D101型大孔吸附树脂分离纯化追风伞总黄酮的最佳工艺条件为:上样液浓度1.839 mg.mL-1,上样流速为2.0 mL.min-1,洗脱剂为70%乙醇,洗脱剂用量为6 BV。在此条件下,D101型大孔吸附树脂对追风伞总黄酮的动态饱和吸附量为80.05 mg.g-1,纯化后追风伞总黄酮的纯度达到86.2%。D101型大孔吸附树脂可以较好地分离纯化追风伞总黄酮。  相似文献   

6.
研究通过静态吸附/解吸实验对大孔吸附树脂进行筛选,优选AB-8大孔吸附树脂作为层析柱填料,并对其进行喜树碱纯化工艺研究;研究表明AB-8树脂对喜树碱的静态吸附率为95.31%;体积分数95%的乙醇静态解吸率为92.4%;最佳吸附条件为:上样液质量浓度为0.175mg/mL,上样液不调pH值,吸附流速为2BV/h,平衡吸附5h;最佳洗脱条件:体积分数95%乙醇,洗脱流速1BV/h,洗脱体积为8BV。在该工艺条件下,洗脱物中喜树碱质量分数为7.43%,洗脱率为83.1%。  相似文献   

7.
探讨大孔吸附树脂纯化马缨丹总黄酮的最佳工艺,通过对4种型号大孔树脂的静态实验,筛选出最佳树脂;考察最佳树脂对马缨丹总黄酮的吸附及洗脱性能,优化工艺参数。结果表明:AB-8为最佳树脂,其最佳工艺条件为:上样液质量浓度0.198 mg/mL,吸附流速为2.0 mL/min,吸附pH为4.0;洗脱剂为70%乙醇,洗脱用量5 BV,减压浓缩得马缨丹总黄酮浸膏,纯度为32.45%。  相似文献   

8.
研究了大孔吸附树脂富集款冬花总黄酮的工艺。从5种大孔吸附树脂中筛选出AB-8型大孔吸附树脂适合富集款冬花总黄酮,并通过单因素实验确定适宜的富集工艺为:将4BV的款冬花样品液以3BV·h-1的速度上样,吸附40min,用4BV的纯化水以6BV·h-1的速度冲洗杂质,再用4BV的60%乙醇洗脱总黄酮。该树脂稳定性良好,可连续使用6次。  相似文献   

9.
树脂法精制蜂胶高生物活性黄酮醇   总被引:1,自引:0,他引:1  
考察了5种树脂对蜂胶中的水溶性黄酮醇的吸附和洗脱性能。以质量分数为65%的乙醇为提取剂,提取温度为38℃,以质量分数为60%的乙醇洗脱,通过比较吸附量、洗脱率以及所得水溶性黄酮醇的含量,最后得出以V(D4020)∶V(聚酰胺)=2∶1的混合型树脂为最佳选择。采用该种树脂,水溶性黄酮醇的最大吸附量为32.76mg/mL,洗脱率为94.68%,提取率为8.27%。  相似文献   

10.
采用静态吸附方法从7种大孔吸附树脂中选择出最佳树脂,采用动态吸附的方法选择出分离皂角刺总黄酮的最佳工艺。结果 AB-8大孔吸附树脂对皂角刺中总黄酮分离纯化效果较好;最佳工艺条件为:0. 2 g/mL的皂角刺提取液、2 mL/min的上样流速、洗脱剂为70%的乙醇溶液、2 mL/min的洗脱流速。故采用AB-8大孔吸附树脂分离纯化皂角刺总黄酮,其含量可达到62. 5%。  相似文献   

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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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14.
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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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   

18.
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   

19.
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   

20.
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   

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