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1.
采用硅胶柱色谱及HPLC等分离方法对苹果树皮正己烷提取物进行分离纯化,得到6个单体化合物,依据波谱数据分析鉴它们的结构分别为:木栓酮(1),羽扇豆醇(2),3-β-齐墩果醇(3),软脂酸(4),3-β-齐墩果醇-18-烯(5),β-谷甾醇(6)。其中化合物3, 4,5为首次从苹果属植物中分离得到,化合物1为首次从该植物中分离得到。  相似文献   

2.
 对产于云南绿春异型南五味子(Kadsura heteroclita(Roxb.)Craib)的化学成分进行研究.采用硅胶柱层析、重结晶等分离手段从中分离纯化得到8个化合物,通过现代波谱技术和理化常数测定鉴定了它们的结构,分别为kadsudilactone(1),长南酸(changnanicacid2),nigranoicacid(3),acetylaleuritolicacid(4),(+)-dihydrodehydrodiconiferylalcohol-9-O-β-D-glucopyranoside(5),isolariciresinol-9-O-β-D-xylopyr-anoside(6),β-谷甾醇(β-sitosterol7),胡萝卜苷(daucosterol8).化合物1,5和6为首次从该植物中分离得到,化合物5和6则首次从南五味子属植物中分离得到.  相似文献   

3.
目的:研究线纹香茶菜地下块状根茎的化学成分。方法:用70%丙酮冷浸提取,相关部位的主要成分通过硅胶柱层析分离纯化,依据现代波谱技术及与标准品对照的方式进行结构鉴定。结果:由乙酸乙酯部位分离得到6个化合物,分别鉴定为β-谷甾醇(1),3β-乙酰基齐墩果酸(2),3β-乙酰基乌苏酸(3),油酸(4),花柏酚(5),山楂酸(6)。结论:上述成分均为首次从该植物地下块状根茎中分离,其中2~6为首次由该植物中获得。  相似文献   

4.
利用色谱法从民间药蓼科酸模属植物戟叶酸模的95%乙醇提取物中分离得到6个木脂素苷类化合物.根据化合物的理化性质及波谱数据分析,将其分别确定为schizandriside(1),(-)-isolariciresinol-9-O-β-D-xylopyranoside(2),(+)-5-methoxyisolariciresinol-9-O-β-D-xylopyranoside(3),(-)-5-methoxyisolariciresinol-9-O-β-D-xylopyranoside(4),lyoniside(5),nudiposide(6).所有化合物均为首次从该种植物中分离得到.  相似文献   

5.
水杨梅化学成分研究   总被引:1,自引:0,他引:1  
采用柱色谱技术,对水杨梅的化学成分进行分离,从水杨梅乙醇提取物的乙酸乙酯萃取部位分离得到3个化合物,从正丁醇萃取部位分离得到4个化合物;根据光谱分析和文献对照的方法鉴定它们的结构分别为:异香草酸(1),七叶内酯(2),咖啡酸(3),5-hydroxy-2-methylchromone-7-O-β-D-xylopyranosyl(1→6)-β-D-glucopyranoside(4),东莨菪素(5),7-O-β-D-glucosyl-noreugenin(6),东莨菪苷(7).化合物1、2、3和7为首次从该植物中分离得到.  相似文献   

6.
采用薄层色谱,正相、反相硅胶,葡聚糖凝胶,半制备高效液相柱对土贝母正丁醇部位进行了分离研究.分离得到10个化合物,分别为:6-C-葡萄糖-5,7,3′,4′-四羟基黄酮(1),胡萝卜苷(2),胡萝卜苷棕榈酸酯(3),豆甾醇(4),β-谷甾醇(5),β-谷甾醇棕榈酸酯(6),正丁基-β-D-吡喃果糖苷(7),大黄素(8),大黄素甲醚(9),麦芽酚(10).除化合物(8)外,其余化合物都是首次从该植物中分离得到.  相似文献   

7.
采用硅胶柱色谱、制备薄层色谱、凝胶柱色谱和半制备高效液相色谱等方法,从海南暗罗根的乙酸乙酯部位中分离获得7个单体化合物,结构分别为:debilone(1),trans-Nferuloyltyramine (2),3,4,5-trimethoxybenzoic acid (3),p-hydroxybenzaldehyde (4),phydroxybenzoic acid(5),β-sitostenone(6),β-sitosterol(7),其中化合物11-5为首次从该植物中分离得到。  相似文献   

8.
研究东北岩高兰的化学成分。采用硅胶柱色谱及HPLC等色谱技术进行分离纯化,通过理化性质和波谱数据分析鉴定化合物的结构。从东北岩高兰的正己烷萃取物中分离得到6个单体化合物,分别鉴定为:3β-羟基-豆甾烷-4-烯-3-酮(1),叶绿醇(2),24-亚甲基环阿尔廷醇(3),β-谷甾醇(4),熊果醇(5),3β-齐墩果醇(6),化合物1-6均为首次从该植物中分离得到。  相似文献   

9.
从产于云南红河的金平木姜子(Litsea chingpingensis)的乙醇提取物中分离得到5个化合物,包括3个生物碱和2个甾体化合物,经波谱分析确定其结构分别为:boldine(1),norboldine(2),norisoboldine(3),β-谷甾醇(β-sitosterol,4),胡萝卜苷(daucosterol,5).以上化合物均为首次从该植物中分离得到.  相似文献   

10.
目的:研究石竹科蚤缀属植物密生雪灵芝的化学成分,方法:采用多种色谱法分离纯化单体化合物并采用多种波谱法鉴定其结构.结果:分离并鉴定出的5个化合物分别为二十八烷醇(1),小麦黄素(2),β -谷甾醇(3),β-胡萝卜苷(4)和22,23-二氢化菠菜甾醇-3 -0-β-D-葡萄糖苷(5).结论:5个化合物均为首次从该植物中得到.  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.
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   

14.
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   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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