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1.
研究天麻超微饮片的HPLC指纹图谱,考察其有效成分及含量,为天麻超微饮片的质控提供可靠方法。色谱柱为大连依利特公司HypersilBDSC18(4.6mm×200mm,5μm)柱。流动相为0.05%磷酸水溶液洗脱,柱温为25℃,流速为1.0ml·min-1,检测波长为220nm。建立了天麻超微饮片的HPLC指纹图谱,标定了7个共有峰。结论为利用HPLC指纹图谱可以较全面的控制天麻超微饮片的内在质量。  相似文献   

2.
目的 建立远志药材的HPLC指纹图谱,用以鉴别远志与其伪品.方法 采用高效液相法,色谱柱为Hypersil C18柱(4.6 mm×250 mm,5μm),流动相为乙腈-0.5%磷酸(25:75),流速1.0mL/min,检测波长310 nm.结果 建立了正品远志药材的对照指纹图谱,标示了共有指纹峰,可用于区别远志伪品.远志HPLC指纹图谱与其伪品的液相色谱图存在明显的差异.结论 方法简便、特异,可用于远志药材、饮片以及粉末的鉴别,具有较高的实用价值.  相似文献   

3.
采用HPLC法,色谱柱为Dikma Diamonsil C18柱(5μm,4.6 mm×250 mm),以乙腈—水为流动相,梯度洗脱,检测波长254 nm,色谱柱柱温30℃,流速1.0 mL/min.建立了醋莪术饮片HPLC指纹图谱共有模式,标定了8个主要共有峰,并利用计算机辅助相似性评价系统对指纹图谱进行相似度分析,表明相似度较大.实验结果表明:该指纹图谱研究方法简便可靠,重复性好,可作为目前醋莪术配方颗粒内在质量控制有效方法之一.  相似文献   

4.
为探求吴茱萸超微饮片的品种鉴别方法,以来自不同产地的5个吴茱萸样品、7个疏毛吴茱萸和3个石虎样品制成的超微饮片为实验材料,用分子克隆方法获得并测定其ITS序列。标记它们的ITS1,5.8s,ITS2的全长序列,构建了吴茱萸的ITS序列指纹图谱,得出吴茱萸超微饮片3个不同植物来源种内相似度在98%以上;吴茱萸和其变种疏毛吴茱萸及石虎之间的ITS序列有显著的差异,可达27%,而疏毛吴茱萸和石虎的序列差异较小,但是在两组序列的对比中,发现有8个特异位点,显示了这两个亲缘关系比较相近的药材的区别。以ITS序列测定与分析可作为吴茱萸超微饮片的品种鉴定和质量控制的方法。  相似文献   

5.
鱼腥草超微粉黄酮类成分HPLC指纹图谱的研究   总被引:3,自引:0,他引:3  
利用高效液相色谱法建立了鱼腥草超微粉黄酮类成分的色谱指纹图谱。色谱条件:色谱柱为SHIM-PACKVP-C18柱(250mm×4.6mm,10!m),乙腈-1%甲酸梯度洗脱,流速为1.0ml/min,检测波长254nm。建立了鱼腥草超微粉HPLC指纹图谱,标定了7个共有峰。结论为利用HPLC指纹图谱可以较全面地控制鱼腥草超微粉的内在质量。  相似文献   

6.
采用Agilent C18色谱柱(4.6 mm×250 mm,5μm),流动相乙腈-0.05%磷酸水溶液梯度洗脱,流速1.0 m L·min-1,柱温25℃,建立了续断片和盐续断HPLC指纹图谱的测定方法,以川续断皂苷Ⅵ为参照峰,标定了29个共有峰.结果表明,该法重复性好,专属性强,可为续断片和盐续断饮片质量控制提供科学依据.  相似文献   

7.
采用高效液相色谱法建立了壮药龙利叶茎的HPLC指纹图谱。色谱柱为Agilent Eclipse XDB-C18柱(250mm×4.6mm,5μm),以乙腈-0.08%醋酸溶液(体积比)为流动相,梯度洗脱,检测波长为280nm,柱温为25℃,流速为1mL/min,采用《中药色谱指纹图谱相似度评价系统》(2004A版)进行分析。结果表明10批龙利叶茎的HPLC指纹图谱共标定14个共有指纹峰,相似度均达到0.9以上,为建立龙利叶质量控制方法提供了科学依据。  相似文献   

8.
目地建立四川阿坝州产红景天的HPLC指纹图谱,为科学评价与有效控制红景天药材质量提供新方法.方法采用RP-HPLC法测定了阿坝州产红景天18批样品.色谱条件Krosmasil C18柱(250mm×4.6 mm,5μm ),乙腈-0.1%磷酸水梯度洗脱,检测波长275 nm,流速1 mL.min-1,柱温30℃,结果建立了HPLC共有模式指纹图谱,并对药材相似度进行了评价.结论HPLC指纹图谱分析法能简便、科学地控制四川阿坝州产红景天药材的质量.  相似文献   

9.
目的:建立黔产骨碎补药材的HPLC指纹图谱分析方法,为完善黔产骨碎补药材质量控制评价体系提供依据。方法:采用高效液相色谱法,色谱柱为Diamonsil-C_(18)(250 mm×4.6 mm,5μm);流动相为乙腈-0.5%醋酸水溶液,梯度洗脱;柱温为30℃;流速为1.0 mL/min;检测波长为260 nm。采用相似度分析、聚类分析和主成分分析对12批样品的指纹图谱进行分析。结果:建立黔产骨碎补药材的HPLC指纹图谱测定方法,确定了10个共有峰,12批黔产骨碎补药材指纹图谱相似度范围在0.551~0.957;聚类分析的判别距离为20时可聚为三类;主成分分析与相似度分析、聚类分析结果基本一致。结论:所构建的黔产骨碎补HPLC对照指纹图谱及其测定方法,可为骨碎补药材综合质量控制和质量评价提供科学依据。  相似文献   

10.
建立了不同产地龙利叶HPLC指纹图谱,为龙利叶质量控制提供科学依据。采用高效液相色谱法,用Phenomenex(4.6 mm×250 mm,5μm)色谱柱对10批不同产地龙利叶进行分离分析,以乙腈-0.1%冰醋酸为流动相,梯度洗脱,检测波长305 nm,柱温30℃,流速1 mL/min,采用"中药色谱指纹图谱相似度评价系统"(2012.1)软件进行分析。结果表明10批不同产地龙利叶的HPLC指纹图谱共标定8个共有指纹峰,相似度均在0.9以上。该研究为建立龙利叶药材质量控制方法提供了科学依据。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
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   

16.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

17.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

18.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
1 Rise of studies on climate change's effects on biodiversity
Until the 1980s, climate change and biodiversity were studied as two independent disciplines for more than a century. In 1992, the Ecological Society of America's annual report named climate change, biodiversity, and the sustainable ecological system as the three major global environmental issues of the twenty-first century [1].  相似文献   

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