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毛细管电泳对萘普生对映体的分离及定量分析   总被引:1,自引:0,他引:1  
孙翠荣  傅小芸  吕建德  陈耀祖 《分析化学》2000,28(10):1281-1283
以环糊精及其衍生物作为毛细管电泳手性分离的添加剂,采用正极进样,对酸性药物萘普生对映体的分离进行研究,结果表明该途径能在较短的时间内使对映体达到基线分离。还研究了缓冲体系pH值对萘普生对映体分离的影响,结果表明,pH5.5时分离效果最佳,且耗时最短。对CE定量能力(线性,精度)进行了考察,获得满意的结果,线性相关系数为0.998,RSD低于4.4%。  相似文献   
2.
综合利用1H-NMR,13C-NMR,耦合常数及异核远程相关谱(HMBC),对芳香族多取代类似物1,2-二氯-4-甲基-3-硝基-5-三氟甲基苯(NATM)和1,2-二氯-4-甲基-5-三氟甲基苯(FATM)进行了碳氢全归属.  相似文献   
3.
Owing to no complications caused by solid supports, such as adsorptive sample loss and deactivation, tailing of solute peaks, and contamination, countercurrent chromatography (CCC) has been an area of intense research since the first introduction of CCC in 1970,[1] and various apparatus and broad applications have been advanced[2,3]. For these developments, the type-J synchronous planet centrifuge has received considerable attention, which relies not only on its relatively simple mechanic design, but also on its high partition efficiency and short elution time caused by mixing and settling for the efficient chromatographic separations. In the past, however, almost all of type-J centrifuges rotated slowly were disposed horizontally due to the original design and some experiments that gravis plays an important role at a low rotary speed as similar to type-V rotating multilayer helical tube in unit gravity[4-9]. In fact,we discovered that the upright apparatus holds more retention of stationary phase than the horiziontal aparatus when large standard tubings were used as mutilayer coil column and the aparatus was operated under same contions. We report here a new coil planet centrifuge with four upright cylindrical columns for large scale countercurrent chromatographic preparation. The design principle and apparatus of UCCC is as samilar to type-J multilayer coil planet centrifuge. Four uptight cylindrical column holders are symmetrically arranged around the centrifuge axis as similar to the type-J HSCCC with three horizontal multilayer coils connected in series[8] . A series of experiments indicat that upright CCC has many advantages over the horizontal CCC when using a large-bore tube as multilayer coil column for large scale countercurrent chromatographic separation.Upright CCC provide a versatile countercurrent chromatographic method for large-scale preparation from very crude sample. It has good preparative capacity and flexible suitability to various sample and two-phase system.The present apparatus not only can be operated at a high speed as similar as commonly used HSCCC for the system having short settling time and but also can be run at a low speed for the system having relative long settling time. Because of automatical control and seal-free flow through device, the uptight CCC apparatus may be readily scaled up to industrial preparation.  相似文献   
4.
A versatile countercurrent chromatography with upright multilayer coil planet centrifuge, named upright countercurrent chromatography (UCCC), was applied to the isolation and purification of celastrol from the roots of Celastrus orbiculatus Thunb. The crude celastrol was obtained by elution with petroleum ether from ethanol extracts using a 15 cm length and 5 cm I.D. of silica gel flash chromatography. Preparative UCCC (Fig. 1) with a two-phase system composed of petroleum ether (b. p. 60 ~ 90 ℃ )-ethyl acetate-tetrachloromethanemethanol-water ( 1:1:8:6: 1, v/v) was successfully performed, yielding 705 mg celastrol at 99.5 % purity from 1020 rng of the crude extract in one step separation.  相似文献   
5.
以合成的羟丙基-β-环糊精为手性选择剂,考察了HP-β-CD浓度,取代度和取代位置及缓冲溶液pH对4种碱性药物对映体的毛细管电泳分离的影响。结果表明,HP-β-CD浓度和缓冲溶液的pH是碱性药物对映体分离的重要因素,HP-β-CD的取代度和取代位置对分离有明显的影响。在选定条件下,4种试验样品达到较好的分离。  相似文献   
6.
研究手性化合物的分离分析方法是当今国际分析化学领域研究的热点.毛细管电泳(CE)手性分离具有高效、快速、低耗等特点,近年来已取得很大进展[‘j.环糊精(CD)及其衍生物是CE手性分离使用最多的手性选择剂,其手性分离机理是基于手性化合物(客体)的2个对映体与环糊精分子(主体)形成的包合物的稳定常数不同,而这种差别主要取决于主客体分子之间的匹配性.因此,CD及其衍生物的分子结构,包括CD衍生物的取代度和取代位,置,对手性识别有很大影响.目前,有关CD及其衍生物作为手性选择剂的CE手性分离报道较多“‘,研究的主…  相似文献   
7.
孙翠荣 《分析试验室》2003,22(Z1):79-79
托品醇是生物合成和化学合成托品烷类生物碱的重要中间体,具有重要的生理活性和应用开发价值.长期以来,对其立体异构体α-托品醇(图1)和β-托品醇(图2)的鉴别一直采用化学法,不仅极不方便,而且准确性不高.本研究运用一维和二维核磁共振波谱技术,发展了α-托品醇和β-托品醇识别的新方法.  相似文献   
8.
天然来源生物活性成分是药物先导分子的重要源泉之一,它们种类繁多,结构复杂多样,逐一分离提取纯化然后进行结构分析鉴定的这一传统植物化学(天然药物化学)研究模式尽管已沿袭多年,但往往费时费力,目标性不强,且常常忽略含量甚少的微量成分.高效液相色谱及多级质谱联用技术(HPLC/MSn)兼顾了色谱的高效分离能力和质谱的强大定性功能,为天然生物活性成分的分析研究提供了新途径.本文总结了我们课题组近年来对糖苷、植物酚类以及酰胺类生物碱等几类天然有效成分的分析研究进展:应用HPLC/MSn联用技术在线分析鉴定多种天然来源的已知成分,快速筛选出多种未知成分,并运用多级质谱技术获得未知成分的结构信息,为快速准确发现新的目标结构提供靶向指导.这一研究方法的应用,突破了传统分离分析的束缚,为现代植物化学或天然药物化学研究提供了新思路.  相似文献   
9.
A versatile countercurrent chromatography with upright type-J multilayer coil planet centrifuge,named upright countercurrent chromatography (UCCC),was applied to the isolation and purification of amides from Piper Longum L., which is widely used as an anodyne and a treatment for stomach disease in China. After saponification by KOH of the ethanol extracts solution of crud drug "Piper Longi Fructus", the fruits of Piper Longum L., the remaining solution was extracted with petroleum ether and red crude oil was obtained. Using 2.5 g red crude oil as sample, the preparative UCCC with a two-phase system composed of petroleum ether (b. p. 60 ~ 90 ℃)-ethyl acetate-tetrachloromethanemethanol-water ( 1: 1: 8: 6: 1, v/v) was successfully performed, yielding ten fractions. Then these fractions were further purified by use of reversed-phase liquid chromatography with a glass column of 500 × 10 mm I. D.packed with reversed - phase silica gel. As a result,nine amides with more than 98% purity, i.e., (2E,4E)-N-isobutyl-eicosa-2,4-dienamide, (2E, 4E, 8Z)-N-isobutyl-eicosa-2,4,8-trienamide, (2E, 4E, 8Z)-N-isobutyl-ocatadeca-2,4,8-trienamide, guineensine, pipemonaline, ( 2E, 4E )-N-isobutyl-2, 4-didecadienamide, piperine, piperanine, and piperlonguminine were isolated preparatively.  相似文献   
10.
红外导数光谱-统计学法区别鉴定麦冬及其伪品的研究   总被引:12,自引:5,他引:7  
为了建立中药材麦冬及其伪品的直接鉴定的理论和方法 ,采用OMNI采样器直接测定法测定了样品的红外光谱 ,并经过二阶导数光谱转换后进行峰位一致率检验。结果发现麦冬表皮以内部分和外表皮的二阶导数红外光谱峰位基本无差别 ,而且不同产地的道地药材具有较好的相关性。研究中发现浙麦冬与川麦冬表皮以内部分的二阶导数FTIR峰值 (χ2c =891 882 ,P =0 0 0 0 )的差异性极显著 ;与土麦冬 (χ2c=4 2 9 2 17,P =0 0 0 0 )、与湖北麦冬 (χ2c=6 92 70 6 ,P =0 0 0 0 )、与短葶山麦冬 (χ2c=981 970 ,P =0 0 0 0 )、与阔叶山麦冬 (χ2c=716 2 17,P =0 0 0 0 )、与竹叶麦冬 (χ2c=70 1 393,P =0 0 0 0 )的差异性都极显著。实验结果表明二阶导数红外光谱结合统计学法可用于中药材麦冬的真伪鉴别 ,本法简便、快速和准确  相似文献   
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