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1.
AB-8树脂吸附和分离玫瑰红色素   总被引:2,自引:0,他引:2  
马银海  彭永芳  杨艳红  马忠琼 《化学世界》2001,42(6):301-302,295
研究了 AB- 8等树脂吸附和分离玫瑰红色素的方法。试验结果表明 :AB- 8树脂对玫瑰红色素的吸附效果最好 ,被吸附的玫瑰红色素用 80 %乙醇洗脱 ,流速为 0 .33m L/ min。AB- 8树脂非常稳定 ,使用 1 8次后 ,其吸附能力仅降低 1 %左右  相似文献   

2.
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   

3.
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   

4.
以牛心朴子草为原料,采用柱层析、重结晶等方法对经过AB-8大孔吸附树脂处理后的牛心朴子草提取液中化学成分进行了提取和分离。对分离得到的两种化合物采用质谱、红外光谱、紫外光谱等手段进行了表征,鉴定结果分别为:表赤杨醇和磁麻酯。  相似文献   

5.
大孔吸附树脂对葛根总黄酮吸附性能的研究   总被引:7,自引:0,他引:7  
测定分析了AB-8等6种不同极性大孔吸附树脂对葛根总黄酮的吸附特性。静态实验结果表明,树脂的极性和空间结构是影响吸附效果的重要因素。AB-8树脂孔径适当,比表面积较高,葛根黄酮吸附量达74.3 mg/g。进行了静态吸附动力学的研究,并获得总黄酮吸附量与吸附时间之间的定量关系。动态吸附研究表明,在温度为20℃时,以吸附流速4 mL/min和洗脱流速3 mL/min较合适。而重复使用约10次以后,该树脂应进行再生。  相似文献   

6.
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   

7.
大孔吸附树脂对葡萄籽原花青素的吸附特性   总被引:3,自引:1,他引:3  
杨迎花  李晓丽 《精细化工》2007,24(9):899-902
从9种大孔吸附树脂中筛选出AB-8树脂对原花青素有较好的吸附和解吸性能。研究了原花青素在AB-8树脂上的吸附特性。静态吸附表明,吸附略有放热,平衡吸附时间为2 h,吸附行为更符合Langmuir等温式,用体积分数为50%的乙醇时解吸效果最好。当流速为1.5 BV/h时,动态泄漏吸附量比静态吸附量低15%,5BV可达到完全洗脱的目的,其原花青素的质量分数可达85.8%。  相似文献   

8.
采用静态吸附实验考察了D-101、DM-301、AB-8、D001、D201、D113、D202等大孔树脂对茶皂素的纯化效果,并考察了上样速度、溶剂体积、上样液质量浓度对大孔树脂AB-8动态吸附率的影响以及洗脱液浓度、洗脱速度、洗脱剂体积对动态洗脱率的影响。大孔吸附树脂AB-8纯化茶皂素的最佳工艺条件为:上样液浓度为27 mg/mL,流速为2.5 mL/min,洗脱剂为75%乙醇,用量为上样液体积的2倍,洗脱速度为2.5mL/min,可以得到纯度为85.7%的茶皂素。  相似文献   

9.
采用静态吸附实验考察了D-101、DM-301、AB-8、D001、D201、D113、D202等大孔树脂对茶皂素的纯化效果,并考察了上样速度、溶剂体积、上样液质量浓度对大孔树脂AB-8动态吸附率的影响以及洗脱液浓度、洗脱速度、洗脱剂体积对动态洗脱率的影响。大孔吸附树脂AB-8纯化茶皂素的最佳工艺条件为:上样液浓度为27 mg/mL,流速为2.5 mL/min,洗脱剂为75%乙醇,用量为上样液体积的2倍,洗脱速度为2.5mL/min,可以得到纯度为85.7%的茶皂素。  相似文献   

10.
张进武 《世界农药》2014,(1):31-34,38
通过大孔吸附树脂对申嗪霉素发酵滤液静态吸附和解吸试验,从6种大孔吸附树脂中筛选出分离纯化申嗪霉素最优的树脂,考察了该树脂对申嗪霉素的静态、动态吸附与解吸性能并对吸附与洗脱的最佳条件进行了研究。结果表明:AB-8树脂对申嗪霉素有很好的吸附和解吸性能,其最优的动态吸附工艺条件为:上样液浓度3 000μg/mL,上样量4 BV,上样流速2 BV/h;最优的解吸条件为:洗脱剂为80%乙醇溶液,洗脱液用量3 BV,洗脱流速1 BV/h。在此优化条件下,申嗪霉素的吸附率、解吸率、收率、纯度的平均值分别达到(90.33±0.14)%、(90.87±0.12)%、(82.1±0.1)%和(90.74±0.14)%(n=5)。  相似文献   

11.
12.
It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.  相似文献   

13.
14.
Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.  相似文献   

15.
16.
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   

17.
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   

18.
2008~2009年世界塑料工业进展   总被引:4,自引:1,他引:3  
收集了2008年7月~2009年6月世界塑料工业的相关资料,介绍了2008~2009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、环氧树脂、不饱和聚酯树脂)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   

19.
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   

20.
建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。  相似文献   

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