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1.
以北虫草固体培养残基为实验材料,比较闪式提取、超声波提取和超高压提取培养残基中虫草素的效果,用陶瓷膜过滤提取液,获得虫草素粗提液,利用高速逆流色谱分离制备虫草素,通过LC-MS/MS对产物结构进行鉴定,并验证了虫草素对小鼠S180肉瘤的抑制作用。结果显示,超高压提取培养基中虫草素较好,高速逆流色谱分离纯化条件是以V(乙酸乙酯)∶V(正丁醇)∶V(水)=2∶3∶5的两相溶剂系统,上相为固定相,下相为流动相,流速3.0mL/min,主机转速900r/min,分离温度28℃,以此分离条件经一步洗脱,高速逆流色谱收集馏分,其中峰Ⅲ产物经HPLC检测纯度达97.6%,结构经LC-MS/MS鉴定为虫草素。从100g北虫草培养残基中可制备得虫草素181.90mg,并对其活性验证发现剂量为100mg/kg时小鼠S180肉瘤瘤重抑制率为64.48%。  相似文献   

2.
高速逆流色谱法连续进样,分离制备杭白菊中的小白菊内酯?采用高速逆流色谱法进行分离,以正已烷-乙酸乙酯-甲醇-水(5∶5∶6∶4,V/V)为溶剂系统,上相为固定相,下相为流动相,连续进样3次,浸膏进样量330?350?370 mg,转速800 r/min,流速2.0 mL/min,检测波长254 nm?从杭白菊超声提取物中,分离得到小白菊内酯5.0?5.2?5.5mg,纯度分别为93.1%?92.6%?92.9%?利用连续进样的高速逆流色谱法,可高效分离和纯化杭白菊中的小白菊内酯?  相似文献   

3.
高速逆流色谱制备雷酚内酯异构体的研究   总被引:1,自引:1,他引:0  
以选定的溶剂体系为基础,研究温度、转速对高速逆流色谱技术分离制备雷酚内酯异构体工艺的影响。研究结果表明,在选定的溶剂体系(正己烷∶乙酸乙酯∶甲醇∶水=2∶3∶3∶2,V/V/V/V)下,流动相流速为2.0 mL/min时,正向洗脱,分离较佳的恒温水浴循环水温度为25.0℃、转速为800 r/min,此时管柱内固定相的保留率为60.0%,管路工作压力为0.15 MPa。  相似文献   

4.
高速逆流色谱分离纯化灯盏细辛中的黄酮类化合物   总被引:1,自引:0,他引:1  
采用高速逆流色谱技术快速分离纯化灯盏细辛中的黄酮类化合物,以石油醚-乙酸乙酯-甲醇 水(4:6:3.5:6.5,V/V)为溶剂系统,转速850 r/min,流速2.0 mL/min,检测波长254 nm。从500 mg粗提物中分离得到4个黄酮类化合物:黄芩素 (87 mg)、木犀草素 (35 mg)、槲皮素 (46 mg)和芹菜素 (92 mg),经高效液相色谱法分析,其纯度分别为94.6%、92.5%、98.2%、97.5%。研究结果表明,应用高速逆流色谱分离灯盏细辛中的黄酮类化合物快速、高效且纯度高。  相似文献   

5.
利用高速逆流色谱对两株昆虫病原真菌蜡蚧霉发酵液的乙酸乙酯粗提物进行分离纯化,GC/MS对分离物进行检测.结果表明:利用高速逆流色谱经两相溶剂系统:正己烷-乙酸乙酯-甲醇-水(4∶5∶4∶5)均可从两菌株代谢产物中分离纯化得到邻苯二甲酸二丁酯,研究发现蜡蚧霉代谢产物中存在天然的邻苯二甲酸二丁酯.  相似文献   

6.
采用高速逆流色谱对波棱瓜子乙酸乙酯提取物进行分离纯化,以石油醚-乙酸乙酯-甲醇-水(体积比2:6:3:5)为溶剂,上相为固定相,下相为流动相,流速2 mL/min,转速850 r/min,共分离得到2个高纯度化合物,经过高效液相色谱检测,纯度均高于95%。该方法简便、快速、节省溶剂,可以对波棱瓜子中的化学成分进行快速有效的分离纯化。  相似文献   

7.
高速逆流色谱(盐溶液体系)分离制备白芍中的芍药苷   总被引:1,自引:0,他引:1  
建立应用高速逆流色谱分离纯化芍药中的芍药苷的方法。以正丁醇-乙酸乙酯-5%Na2SO4(4:1:5,V/V)为两相溶剂体系,在流速为2.0 mL/min、主机转速为800 r/min、检测波长为254 nm的条件下进行分离,从100 mg芍药粗提物中一次性分离制备得到56.13 mg芍药苷,高效液相色谱分析其纯度在98%以上,通过质谱、核磁共振氢谱和核磁共振碳谱鉴定化合物的结构。该方法简便、快捷且重现性好,适合芍药苷的制备型分离。  相似文献   

8.
应用高速逆流色谱分离制备甘草中的芒柄花苷。将甘草乙酸乙酯提取物先经聚酰胺柱色谱分离,所得组分Fr1再用高速逆流色谱进一步分离,采用的两相溶剂系统为乙酸乙酯-水(5:5,v/v),以其上相作固定相,下相为流动相,主机旋转方向顺时针,转速850 r/min,流速2.0 mL/min,检测波长254 nm,从80 mg组分Fr1中得到12.3 mg纯度为99.3%的芒柄花苷。所得产物的结构经NMR鉴定。利用该方法可以对甘草中的芒柄花苷进行快速的分离和纯化。  相似文献   

9.
采用高速逆流色谱结合半制备液相色谱技术快速分离山楂叶中低含量的牡荆素、金丝桃苷、异槲皮苷单体。以氯仿-甲醇-水-正丁醇(4∶3∶2∶1.5,V/V)为溶剂系统,流速为5.0 m L/min,转速为850 r/min,检测波长为254 nm,从山楂叶黄酮提取物中富集得到含牡荆素、金丝桃苷、异槲皮苷3种化合物的混合组分,经半制备液相进行二次分离纯化,得到纯度大于98%的牡荆素、金丝桃苷、异槲皮苷单体。研究结果表明,该技术对山楂叶中低含量黄酮类化合物的分离快速、高效,且纯度高。  相似文献   

10.
采用pH区带精制逆流色谱技术(pH-ZRCCC)快速分离纯化丹参中的丹酚酸B和迷迭香酸?以乙酸乙酯-水(1∶1,V/V)为溶剂体系,上相加入三氟乙酸,使浓度达到10 mmol/L,作为固定相;下相加入氨水使浓度达到20 mmol/L,作为流动相;设置主机转速为850 r/min,流速为2.0 mL/min,检测波长为280 nm,对样品进行分离制备?从500 mg丹参粗提物中一次分离得到386 mg丹酚酸B以及25 mg迷迭香酸,经HPLC分析纯度分别为96.3%和98.1%,各化合物通过电喷雾电离(ESI)谱和1H-NMR进行了化学结构鉴定?研究结果表明,pH-ZRCCC是一种快速?高效分离纯化丹酚酸B和迷迭香酸的方法  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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