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1.
维药祖卡木颗粒总蒽醌含量测定   总被引:1,自引:0,他引:1  
测定维药祖卡木颗粒总蒽醌的含量,以进一步控制其质量。以大黄素为标准对照品,以醋酸镁甲醇溶液为显色剂,采用分光光度法测定祖卡木颗粒中游离、结合和总蒽醌含量。大黄素在8.2—61.5μg/mL^-1范围内线性良好;回收率为102.84%,RSD=3.0%(n=6)。该法准确、可靠、稳定,适合于维药祖卡木颗粒中蒽醌的含量测定。  相似文献   

2.
毛头牛蒡子总木脂素含量测定   总被引:3,自引:0,他引:3  
文章测定毛头牛蒡子中总木脂素的含量。利用紫外分光光度计,以牛蒡苷为对照品,在280nm波长下测定总木脂素含量。对照品牛蒡苷在0.0207~0.1101mg/mL(r=0.9992)浓度范围内吸光度与浓度呈良好的线性关系,平均加样回收率98.3%,RSD=1.8%(n=5)。总木脂素平均含量为244mg/g,RSD=2.9%(n=5)。紫外分光光度法测定总木脂素含量,简单,稳定可靠,重现性好。  相似文献   

3.
乳香中乙酸辛酯含量的测定   总被引:1,自引:0,他引:1  
目的:建立气相色谱法测定乳香中乙酸辛酯含量.方法:采用气相色谱法Agilent6890N气相色谱仪,检测器FID,Agilent19091-413HP-5毛细柱(30m×0.32mm×0.25μm).结果:乙酸辛酯含量在26.40~132.00μg范围内呈良好线性关系(r=0.9993),平均回收率为100%,RSD为2.76%(n=5).结论:气相色谱法测定乳香中乙酸辛酯含量方法操作简单,结果准确,重现性好.  相似文献   

4.
提出基于在碱性条件下,Se(Ⅳ)催化硫代乙酰胺还原亚甲基蓝的反应作为指示反应,测定痕量硒的新催化动力学分析法。研究了催化反应的条件和影响因素,采用起始斜率法,测定了枸杞子样品中的微量硒含量,当硒含量在0.1~1.0μg/15mL范围内与褪色反应速率(d△A/dt)成正比,回归方程为y=0.0195x-0.0024,相关系数r=0.995。用于枸杞子中的硒的测定,测定结果的相对标准偏差为5.4%(n=4),加标回收率为90%~96%。  相似文献   

5.
目的:采用高效液相色谱法测定贯叶连翘中的金丝桃素、黄酮(槲皮素)的含量。方法:色谱柱为Phenomenex LunsC18(4.6mm×150mm,5μm),检测波长分别为590nm和360nm,流动相分别为甲醇:0006mol/L磷酸氢二钠溶液(87:13)和甲醇:水:磷酸(55:44.8:0.2)。结果:线性范围分别在0.027-0.135μg和0.052~0.26μg内良好,回收率分别为:98.39%(n=5)和98.85%(n=5)。RSD分别为0.78%和1.02%。结论:方法能用于贯叶连翘中的金丝桃素、黄酮(槲皮素)的含量测定。关键词:贯叶连翘;槲皮素;金丝桃素;含量测定  相似文献   

6.
天山花楸中总黄酮和槲皮素测定   总被引:2,自引:0,他引:2  
以芦丁、槲皮素为标准品建立了用分光光度法测定天山花楸叶中总黄酮的含量和果实中槲皮素含量的测定方法,分别采用5% NaNO2~10%Al(NO3)3~4%NaOH和2%AlCl3显色系统,并分别在510nm和422nm处进行了含量测定。结果表明:天山花楸果实中总黄酮为7.75%(RSD%=1.09),在1.596~6.384mg/100mL(R^2=0.9999)范围内,线性关系良好;7月天山花楸叶子中槲皮素为0.777%(RSD%=0.66)、8月其叶子中槲皮素为0.397%(RSD%=0.81),叶子中槲皮素在0.241~0.723mg/100mL(R^2=0.9995)范围内,线性关系良好。  相似文献   

7.
RP-HPLC法分析罗红霉素含量   总被引:2,自引:0,他引:2  
目的建立用RP-HPLC法分析罗红霉素药物含量的方法。方法以安捷伦ZORBAX Eclipse XDB—C18柱为色谱柱、乙腈(0.010moL/L)醋酸铵缓冲液(体积比70:30,pH=6.5)为流动相,选择220nm为检测波长;柱温40℃,用反相高效液相色谱法测定罗红霉素(Roxithromyein,RM)的含量。结果罗红霉素的浓度在1.150~100.8mg,/L范围内与峰面积呈良好线性关系,r=0.99977,平均回收率为99.57%,相对标准偏差为1.23%(n=5)。结论该方法操作简单、快速,可用于罗红霉素含量的测定。  相似文献   

8.
HPLC测定大风丸中芍药苷的含量   总被引:2,自引:0,他引:2  
目的——建立大风丸中芍药苷的含量测定方法。方法——采用高效液相色谱法测定,用C18柱(3.9×150mm,5μm),以1%磷酸-乙腈(88:12)为流动相,检测波长231nm。结果——芍药苷的线性范围为0.094μg~0.94μg;r=0.9999,芍药苷平均回收率为99.73%,RSD=0.52%(n=5)。结论——所用方法测定样品灵敏度高,重复性好,能有效地控制大风丸的质量。  相似文献   

9.
目的建立香柏Sabinapingii (Cheng ex Ferre) vat. wilsonii (Rehd.) Cheng et L.K.Fu总酚酸的含量测定方法.方法用没食子酸做对照品,体系中加入o.3%十二烷基磺酸钠溶液2mL,0.6%FeCl3—0.9%K3[Fe(CN)6](1:1)混合溶液1mL,用lmol/L的盐酸溶液定容.采用分光光度法在701.5nm处测定吸光度.结果5批香柏药材的平均含量为(1.441%),RSD=0.0224%.结论本实验中建立的方法方便准确,可用于香柏总酚酸的含量测定.  相似文献   

10.
本实验利用分光光度法对蒙药黑冰片中钛的含量进行了测定,测得标准曲线的回归方程为:A=0.00573+0.048C(r=0.9998).检测限为3~15μg/mL.回收率为99%~102%,RSD为0.89%(n=5),该方法操作简单,灵敏度高,可以推广使用.  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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