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1.
建立高效液相色谱法测定青钱柳中槲皮素、山柰素的含量,并测定黔东南州不同产地青钱柳中槲皮素、山柰素的含量。高效液相色谱法,色谱柱Symmetry C18(5μm,150×4.6 mm,Waters);流动相:甲醇-0.4%磷酸溶液(50;50);检测波长:360 nm;柱温:30℃;流速:1.0 m L·min-1;进样量:10μl。经实验得知黔东南州不同产区的青钱柳中槲皮素、山柰素含量存在一定的差异,槲皮素的含量范围大概为0.663 2~0.814 7 mg/g;山柰素的含量范围大概为0.587 1~0.715 5 mg/g。  相似文献   

2.
高效液相色谱法测定鱼腥草不同部位中槲皮素的含量   总被引:1,自引:0,他引:1  
建立一种快速、简便、准确测量鱼腥草中槲皮素含量的方法。5%盐酸乙醇提取鱼腥草中槲皮素,在流动相:乙腈-0.4%磷酸(v/v=45:55),流速:1.0mL/min,检测波长:370nm条件下高效液相色谱法(HPLC)进行检测。槲皮素线性范围为0.0012~0.12mg/mL,r=0.9997;平均回收率为91.93%,RSD=2.71%。本法操作简便、准确,重复性好,可用于槲皮素含量的测定。同时,对鱼腥草不同部位槲皮素含量进行测定,表明不同部位的鱼腥草中槲皮素含量差异很大,为评价其资源的开发利用提供依据。  相似文献   

3.
目的:测定不同产地不同采收期岩陀药材中槲皮素的含量。方法:采用HPLC法测定岩陀药材中槲皮素的含量。流动相甲醇-0.5%磷酸溶液(50∶50),检测波长370 nm,流速1.0 mL/min,柱温30℃。结果:岩陀药材中槲皮素含量差异较大,不同产地同一采收期的含量范围为0.129%~0.207%;不同采收期同一产地的含量范围为0.074%~0.129%。结论:该方法操作简便,结果准确,重复性好,可为该药材合理开发利用提供科学依据。  相似文献   

4.
采用反相高效液相色谱法(HPLC)和紫外分光光度法测定不同产地文冠木中槲皮素和总黄酮的含量.结果显示HPLC测定槲皮素含量在0.40μg/mL-8.0μg/mL范围内与峰面积线性关系良好(r=0.9992),平均加样回收率为99.00%,(RSD=2.44%);7个不同产地的文冠木中槲皮素含量为0.0088%-0.0143 %,总黄酮以芦丁计在8μg/mL-48μg/mL范围内与吸光度呈良好的线性关系(r=0.9993),平均加样回收率为101.3%,(RSD=1.45%);7个不同产地的文冠木中总黄酮含量为3.27%-10.57%.不同产地的总黄酮含量分布与槲皮素基本相似,其中以内蒙古鄂尔多斯产文冠木中的槲皮素和总黄酮含量最高,安徽毫州产的最低.该方法准确、灵敏、稳定,可用于文冠木药材的质量监控与评价.  相似文献   

5.
采用HPLC法同时测定罗布麻浸膏粉中金丝桃苷、异槲皮苷、槲皮素的含量.色谱柱为YMC-Pack C18(250×4.6 mm),流动相为乙腈-甲醇(10∶1)和0.4%磷酸,梯度洗脱;二极管阵列检测器:检测波长360 nm;分别以金丝桃苷、异槲皮苷、槲皮素对照品为外标,用标准曲线法进行定量.在0.25~10μg/mL的范围内,金丝桃苷、异槲皮苷、槲皮素的浓度与吸收峰面积之间线性关系良好,相关系数分别为r金丝桃苷=0.999 4、r异槲皮苷=0.999 5、r槲皮素=0.999 6,回收率在85.57%~99.96%之间(RSD小于4.45%).  相似文献   

6.
为了解不同炮制方法对槐花有效成分百分含量的影响,利用紫外分光光度法对不同炮制方法炮制后的槐花中芦丁、槲皮素进行测定,比色法对鞣质的测定,从而比较不同炮制方法对槐花有效成分百分含量的影响.芦丁百分含量由高到低的排列顺序为:炒槐花醋炙槐花生品槐花槐花炭,醋炙槐花和炒花槐差别不明显;槲皮素百分含量由高到低的排列顺序为:槐花炭炒槐花醋炙槐花生品槐花;鞣质百分含量由高到低的排列顺序为:炒槐花醋炙槐花生品槐花槐花炭.结果表明,不同炮制方法的槐花中有效成分有一定差异.芦丁随着炮制温度的升高百分含量增加,但在一定温度后呈递减趋势;槲皮素会随时间增加逐渐增加;鞣质随炮制温度增加而增加,当到达一定加热温度后随时间增加变小.  相似文献   

7.
槐米中芦丁和槲皮素的毛细管电泳-电化学检测   总被引:12,自引:0,他引:12  
用毛细管区带电泳 -电化学检测法测定了中药槐米中芦丁和槲皮素的含量。研究了电极电位、电解液酸度和浓度、电泳电压及进样时间等对电泳的影响 ,得到了较为优化的测定条件。以直径为 30 0 μm的碳圆盘电极为检测电极 ,电极电位为 0 .90V (vs .SCE) ,在 10 0mmol/L硼酸盐缓冲液 (pH 9.0 )中 ,上述两组分在 10min内完全分离。芦丁和槲皮素浓度与电泳峰电流分别在 7.5× 10 - 7~ 1.0× 10 - 3和 5 .0× 10 - 7~ 1.0× 10 - 3mol/L范围内呈良好线性 ,检测下限分别为 4 .34× 10 - 7和 2 .2 5× 10 - 6 mol/L。 7次测定含 5 .0× 10 - 4 mol/L芦丁和槲皮素的试样溶液 ,峰高的相对标准偏差分别为 2 .5 6 %和 4 .11% ,五次测得的平均回收率分别为 97.80 %和 96 .84 %  相似文献   

8.
催化动力学光度法测定漏芦花中槲皮素   总被引:1,自引:1,他引:0  
基于稀H2SO4介质中,槲皮素对KBrO3氧化甲基橙褪色反应的明显催化作用,建立了测定槲皮素含量的动力学光度法.采用回流法提取漏芦花中槲皮素,用催化动力学光度法测定其含量,检测波长为517nm,当甲基红、硫酸、KBrO3的用量分别为1.00 mL、0.30mL、0.25 mL,反应温度80 ℃,反应时间5 min时,该法测定槲皮素的线性范围为0.00~0.05 mg/L,检出限为0.002mg/L.样品中槲皮素平均含量为0.269×10-3mg/g(n=5),平均回收率介于92.48%~95.10%.  相似文献   

9.
通过与水浴回流法比较,建立了全自动加压溶剂萃取法,可简单、快速测定洋葱中保健活性物质芦丁和槲皮素含量.采用高效液相色谱仪在368nm波长处测定芦丁和槲皮素含量.色谱柱为C18柱,流动相为甲醇-磷酸溶液(58:42,体积比),以1.0ml/min流速等度洗脱,外标法定量.结果表明,在芦丁和槲皮素质量浓度为0.1~200mg/L时,其线性相关系数均大于0.999.在2.0~100mg/kg的添加水平下,芦丁和槲皮素的平均回收率分别为83.5%~94_2%和84.8%~91.2%;相对标准偏差分别为2.9%~7.4%和4.2%~6.9%(n=6).全自动加压溶剂萃取法的检出限(LOD),芦丁和槲皮素分别为0.05,0.03mg/kg.定量限(LOQ),芦丁和槲皮素分别为0.2,0.1mg/kg.研究建立的运用全自动加压溶剂萃取仪提取、高效液相色谱测定洋葱中芦丁和槲皮素的方法,线性良好,重现性较好,灵敏度较高,能够满足蔬菜和水果等农产品中芦丁和槲皮素的快速检测.  相似文献   

10.
目的:建立高效液相色谱测定沙棘籽粕中槲皮素、山奈酚和异鼠李素含量测定方法.方法:采用Kromasil C18(4.6㎜×250㎜,5μm)色谱柱,流速1 mL/min.流动相:甲醇-水(含磷酸0.04%)为50∶50;检测波长为360 nm;柱温35℃.结果:3种成分均达到基线分离,槲皮素、山奈酚和异鼠李素的线性范围分别为0.0895~1.79μg(r=0.9998),0.0565~1.13μg(r=0.9999),0.088~1.76μg(r=0.9997);回收率为100.7%(RSD=2.1%),98.5%(RSD=1.7%),100.5%(RSD=1.5%).结论:此方法简便、重现性良好、结果准确可靠,可用于槲皮素山柰酚和异鼠李素的含量测定.  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.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
<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   

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