首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
研究了大孔吸附树脂和阳离子交换树脂双柱吸附法对莲心碱、异莲心碱和甲基莲心碱的吸附行为。利用阳离子交换树脂D72制备出莲心碱、异莲心碱和甲基莲心碱,含量分别为10.6%、10.6%和28.0%,总含量为49.2%的莲子心总碱提取物,其中杂质主要是水溶性较大的生物碱成分。利用AKS-W大孔吸附树脂能去除极性较大的生物碱,而D72阳离子交换树脂能去除非生物碱的特点,采用双柱联合吸附法,制备出3种吸附质含量分别为33.1%、15.0%和34.5%,总含量为82.6%的莲子心总碱提取物。  相似文献   

2.
采用单因素试验,对微波辐射-溶剂回流提取法的实验条件进行优化,得到最佳提取条件:药材颗粒度100目,微波功率60%档(总功率为700 W),微波辐射时间90 s,固液比1∶25,提取温度90℃,提取时间45 min。以天芥菜碱和毛果天芥菜碱为提取目标物,通过HPLC法测定其含量,其分析条件为:以乙腈-0.1%乙酸溶液(p H 5.6,体积比5∶95)为流动相,在220 nm处检测。毛果天芥菜碱和天芥菜碱的浓度在50~900 mg/L范围内均呈良好线性关系,检出限分别为1.50 mg/L和1.52 mg/L,加标回收率分别为95.0%~98.5%和96.5%~101%,RSD分别为1.8%和2.4%,方法简单、灵敏度高。  相似文献   

3.
大孔吸附树脂纯化石蒜中石蒜碱   总被引:3,自引:0,他引:3  
比较了9种大孔吸附树脂对石蒜碱的吸附率和解吸率,确定了HPD300为优选吸附树脂,研究了该树脂纯化石蒜碱的条件及参数. 室温下,9 BV 1.22 g/L的石蒜碱上样液以2 BV/h过柱,4 BV水以2 BV/h洗涤后用8 BV 70%乙醇以2 BV/h洗脱,石蒜碱的纯度由9.93%提高至23.07%.  相似文献   

4.
以阿卡波糖为原料制备α-糖苷酶抑制剂Valienamine,通过对比硫酸、三氟乙酸和强酸型阳离子交换树脂催化水解阿卡波糖的效果,证实强酸型阳离子交换树脂效果最好,并且在催化水解的同时,产物Valienamine生成后即被吸附在树脂上,糖类副产物水洗即可除去;在实验选择的树脂中,以Amberlyst A-15催化活性最强,阿卡波糖水解率可达95.6%,国产001×7树脂水解率虽稍有逊色,但洗脱容易;选择9种大孔吸附树脂分别对Valienamine进行吸附和解析纯化试验,其中H1020型号树脂效果最好,80%甲醇解析效果最好;采用活性炭纯化Valienamine,用量为25mg/g阿卡波穰时,纯化效果最好,本实验条件下得到的Valienamine纯度为98.26%,得率为74.3%.  相似文献   

5.
建立了二(2-乙基己基)磷酸酯(DOLPA)/二(2-乙基己基)丁二酸酯磺酸钠(AOT)-异辛烷反胶束萃取技术结合超高效液相色谱同时测定倒提壶中天芥菜品、天芥菜碱、毛果天芥菜碱及天芥菜定含量的方法。采用单因素试验考察了表面活性剂的种类与浓度、水相p H值、盐的种类与浓度、萃取相比、萃取及反萃取时间等因素对生物碱萃取率的影响。确定最佳萃取条件为:DOLPA/AOT的总浓度为0. 6 mol/L,水相p H值为4. 0,KCl浓度为0. 2 mol/L,萃取相比4∶1,萃取和反萃取时间分别为10、30 min。在优化条件下,以乙腈-0. 2%三乙胺为流动相进行超高效液相色谱法(UPLC)梯度洗脱,可在16 min内完成色谱分析,4种生物碱色谱峰的分离度良好;天芥菜品、天芥菜碱、毛果天芥菜碱及天芥菜定4种生物碱的质量浓度与峰面积呈良好线性关系,检出限分别为0. 030、0. 050、0. 040、0. 020 mg/L,回收率分别为98. 2%~103%、97. 9%~102%、98. 1%~101%、97. 8%~104%,精密度、重复性及加标回收率的RSD均不大于2. 3%。该法简单快捷、灵敏准确,满足倒提壶中4种生物碱的检测要求。  相似文献   

6.
从7种极性不同的大孔树脂中筛选出一种对酸枣仁三萜总皂苷具有良好吸附和解吸性能的树脂—三菱SP700树脂。静态实验中,该树脂的最高吸附容量可达131.0mg皂苷/g树脂,皂苷在树脂表面的吸附符合Langmuir模型,用体积分数为90%的乙醇解吸得率最高可达97.8%;动态实验中,样液在膨胀床模式下上样,树脂的平均动态吸附容量为15mg皂苷/g树脂,上样后,用体积分数分别为50%和90%的乙醇溶液进行分段洗脱,洗脱得率最高可达到95.1%,经过纯化的皂苷提取物的含量提高了4倍。SP700大孔吸附树脂作为一种对酸枣仁中三萜总皂苷进行纯化的介质具有良好的性能和应用价值。  相似文献   

7.
一种用于中药纯化过程的近红外光谱分析新方法   总被引:36,自引:0,他引:36  
针对中药大孔吸附树脂纯化过程缺乏在线检测分析手段等问题,提出基于光纤 近红外透射光谱的过程分析新方法.以黄连提取物为例,采用HPLC分析测定值作参 比,用偏最小二乘算法建立了近红外透射光谱校正模型,并成功地用于预测黄连生 物碱在大孔树脂纯化过程中的洗脱曲线.本方法实时、快速,可同时测定洗脱物中 盐酸小檗碱、盐酸巴马亭、盐酸药相碱和黄连总生物碱的浓度.预测精度满足工业 过程分析要求,为提高中药质量分析水平提供了新的途径.  相似文献   

8.
D241树脂分离纯化黄芩总黄酮的研究   总被引:10,自引:1,他引:10  
本文研究了用241树脂分离纯化黄芩总黄酮的方法和工艺。实验结果表明:D241树脂对黄芩总黄酮的静态交换容量是77mg/ml树脂。在pH11.0、流速2.0BV/h、提取液中总黄酮浓度17.5mg/ml条件下,D241树脂对黄芩总黄酮的动态交换容量为43.8mg/ml。用60%甲醇作为黄芩总黄酮洗脱剂,在PH4.0、洗脱流速1.5BV/h条件下,4.5BV洗脱剂即可完全洗脱被D241树脂交换的黄芩总黄酮。与酸沉淀法相比较,经过除去果胶,总黄酮纯度由33.34%提高到74.9%,粗品收得率由11.52%降低至4.83%;经过D241树脂分离纯化,其纯度达到91.5%,产品收得率3.54%。  相似文献   

9.
阳离子交换树脂二次纯化紫甘薯花色苷的研究   总被引:1,自引:0,他引:1  
采用阳离子交换树脂二次纯化紫甘薯花色苷。以紫甘薯花色苷的吸附率,解吸率和花色苷含量等为考察指标,确定了阳离子交换树脂二次纯化紫甘薯花色苷的工艺条件。研究结果表明,D061树脂对紫甘薯花色苷的吸附量大,解吸容易,可用于二次纯化紫甘薯花色苷的工业化生产,其工艺条件为:上样液的pH值为2.6,上样液吸光度值在0.6×100左右,上样流速为1.0BV/h,50%乙醇(含2%盐酸)为洗脱液,洗脱流速为0.5BV/h,用此工艺条件D061树脂吸附花色苷的吸附量为10.5mg/g,洗脱剂用量为3.0BV,花色苷的收率为82.99%。二次纯化后,紫甘薯花色苷的花色苷含量达到29.38%,色价高达136.80。  相似文献   

10.
大孔吸附树脂分离纯化仙人掌中总黄酮的研究   总被引:3,自引:0,他引:3  
考察了4种大孔吸附树脂对仙人掌总黄酮的吸附分离性能,筛选出效果最佳的树脂为AB-8。以总黄酮的吸附量、总黄酮含量和回收率为考察指标,采用紫外分光光度法测定总黄酮。确定了AB-8树脂吸附分离仙人掌总黄酮的工艺条件:上样浓度为15mg/mL,仙人掌总黄酮最大吸附量为18.6mg/mL,吸附流速为5mL/min,洗脱剂为70%乙醇,洗脱剂用量为6倍柱体积,树脂可重复使用3次。经AB-8树脂分离纯化后,总黄酮含量从29%提高到76%,总黄酮回收率为86%。实验结果表明,AB-8树脂可用于仙人掌总黄酮的分离纯化。  相似文献   

11.
8—羟基喹啉树脂的制备及应用研究进展   总被引:2,自引:0,他引:2  
本文总结了国内外关于8-羟基喹啉螯合树脂的制备方法,树脂性能及其应用。  相似文献   

12.
Due to the rapid depletion of crude oil and serious environmental pollution, the synthesis of polymers from renewable resource is becoming more and more important. Up to now, a great variety of biomass and bio-based platform compounds have been taken to prepare the polymers. However, as two representative thermosetting resins, epoxy and benzoxazine resin derived from renewable feedstocks only obtain limited attention compared with the popular bio-based plastics, including PLA, PBAT and PHBV etc. The reason might be that the properties of previously reported thermosetting resins directly obtained from biomass are usually unsatisfied, and their application fields are limited. In this paper, the latest development on the synthesis of high-performance bio-based epoxy and polybenzoxazine resins are reviewed. In addition, to further broaden their applications, the functionalization strategies are also summarized. The objective of this work is to help us fully aware the present situation of bio-based thermosetting resins and then promote their faster development, especially practical application.  相似文献   

13.
This investigation carries on previous studies on polyacrolein-styrene resins. Further attempts were made to convert the reactive aldehyde groups of the polymeric support to functional acrolein-isonicotinic acid hydrazone (P-NHZ) or acrylic acid-thiohydrazide derivatives (P-THZD). The conditions of synthesis and the basic sorption and desorption properties of the polymers synthesized are described. For gold and platinum group metals the resins show differences in loading capacities, rates of simultaneous sorption in static conditions and efficiencies in column tests. The elution by thiourea solution was utilized to separate Au, Pd and Pt from an excess of base metals. The P-NHZ resin seems to be more advantageous than the sulfur containing P-THZD resin.  相似文献   

14.
用一种硅炔杂化树脂聚(甲基硅烷-二乙炔基苯)(PSP)改性有机硅树脂(HS),通过FT—IR和TGA研究了树脂体系的固化反应及耐热性,并对制备的复合材料进行力学性能、耐热性能和介电性能研究。结果表明:当HS与PSP的质量比为5:5时综合性能最优,树脂体系在氮气氛围下质量损失5%时的温度(T幽)为691℃,1000℃时质量保留率为88%;HS—PSP树脂短切玻纤复合材料冲击强度为21kJ/m^2,弯曲强度为65MPa,200℃时的弯曲强度高温保留率为78%,介电常数为4.6,介电损耗因数为7.9×10,体积电阻为6.7×10^13Ω。改性后的复合材料具有优异的力学、耐热和介电性能。  相似文献   

15.
Cardanol-based epoxidized novolac vinyl ester resin (CNEVER) was synthesized by reacting cardanol-based epoxidized novolac (CNE) resin and methacrylic acid (MA) (CNE:MA molar ratio 1:0.9) in presence of triphenylphosphine as catalyst at 90 °C. The CNE resin was prepared by the reaction of cardanol-based novolac-type phenolic (CFN) resin and epichlorohydrin, in basic medium, at 120 °C. The CFN resin was synthesized by reacting cardanol (C) and formaldehyde (F) (C/F ratio = 1:0.7) with p-toluene sulphonic acid (PTSA) as catalyst (0.5 wt.%) at 120 °C for 7 h. The resin products were analyzed by Fourier-transform infra-red (FTIR) and nuclear magnetic resonance (NMR) spectroscopic analysis. The number-average molecular weight of the prepared CNEVER was found to be 859 gmol−1 as determined by gel permeation chromatographic (GPC) analysis. The resin was cured by using the mixture of resin, benzoyl peroxide, and styrene at 120 °C. The CNEVER resin was found to be cured in 60 min at 120 °C. Differential scanning calorimetric (DSC) technique was used to investigate the curing behaviour. Single step mass loss in dynamic thermogravimetric (TG) trace of CNEVER was observed. Thermal stability of the vinyl ester sample containing 40 wt.% styrene was the highest amongst all other prepared systems.  相似文献   

16.
研究了磺化三聚氰胺甲醛树脂(SMF)与金属钙离子的复合物SMF-Ca^2 对水泥的作用,从对水泥吸附、水化等研究结果表明,SMF和Ca^2 间存在着一定的化学作用。在水泥砂浆中加入SMF-Ca^2 复合物比加入纯的SMF树脂能使减水率、抗压强度、抗折强度获得更大的提高。  相似文献   

17.
苯氧树脂增韧双酚A环氧树脂的研究   总被引:5,自引:0,他引:5  
以双官能团环氧树脂和双酚A为单体,制备高分子量苯氧树脂,通过FTIR对其分子结构进行分析后,将10wt%苯氧树脂加入到E-44环氧树脂中,用DSC冲击仪和SEM等对增韧效果的分析测定,固化反应活化能降低9%,冲击强度提高63.2%,玻璃化温度提高了28℃。  相似文献   

18.
红外光谱测试结果表明糖醇树脂碳化过程中五员杂环上的碳氧键首先发生断裂,使氧脱出,而剩余的双烯链状结构再进行重排,形成六员稠环结构,并在此基础上发生脱氢反应生成石墨微晶。测试结果还表明聚苯胺树脂中的氮在碳化过程中的稳定性与其相连结的基团结构有密切关系。苯环相连的氮比与苯酚基相连的氮具有更强的抗热解稳定性。聚苯胺碳化产物中的氢主要分为两大类:一类是以碳氢键的形式存在;另一类则是以氮氢键的形式存在。碳化产物中的氢主要是在苯的稠环结构上以碳氢键形式存在。  相似文献   

19.
Polystyrene-supported N-phenyl-N-acyl sulfonamide resin was prepared by reacting polystyrene sulfonyl chloride resin with aniline and acylating in pyridine with either acid chlorides or anhydrides. Then, this resin was utilized as a new type of acyl transfer reagent to synthesize the amide library. It was approved to be a more effective acyl transfer reagent with higher amide yields than the polystyrene-supported N-methyl-N-acyl sulfonamide resin and N-benzyl-N-acyl sulfonamide resin. When the phenyl group bonded to the N atom on N-phenyl-N-acyl sulfonamide resin was substituted by the electron withdrawing group or electron donating group, a decreasing amide yield was obtained. N-phenyl-N-acyl sulfonamide resin could be regenerated many times.  相似文献   

20.
采用预共聚法,以含硅芳炔树脂(PSA)和端乙炔基聚醚酰亚胺(PEI)为原料,制备了端乙炔基聚醚酰亚胺改性的含硅芳炔(PEI-PSA)树脂及其与T300碳纤维平纹布的复合材料T300/PEI-PSA。通过动态热机械分析(DMA)和X射线能谱仪(EDS)研究了溶剂、溶液浓度、反应温度对预共聚反应的影响,确定了预共聚反应的最佳条件,得到了均匀分散的PEI-PSA树脂。通过红外光谱(FT-IR)、核磁共振氢谱(1 H-NMR)、差示扫描量热(DSC)、热失重(TG)、DMA和EDS等表征了PEI、PEI-PSA树脂及T300/PEI-PSA复合材料的结构和性能。结果表明,当PEI质量分数为20%时,PEI-PSA树脂浇铸体的弯曲强度达44.5 MPa,较PSA树脂浇铸体提高了90.2%;T300/PEI-PSA复合材料的弯曲强度达602.7 MPa,较T300/PSA复合材料的弯曲强度提高了124%。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号