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1.
生物柴油中脂肪酸甲酯成分的气相色谱法测定   总被引:7,自引:0,他引:7  
采用气相色谱法,以环己酮为内标,柱程序升温测定生物柴油中脂肪酸甲酯成分以及含量。结果表明:各脂肪酸甲酯在4~32 mg/mL浓度范围内,其峰面积与内标峰面积的比对浓度具有良好的线性(R>0.9975)。回收率在97.40%~102.152%之间(n=6),精密度实验中相对标准偏差为0.17%~1.79%(n=6)。  相似文献   

2.
用高效毛细管电泳法测定姜黄素类化合物中姜黄素的含量.姜黄素在0.450~4.049 g/L内峰面积和浓度有良好的线性关系(r=0.999 2).方法的精密度RSD=1.25%(n=6),平均回收率为99.8%.适用于含姜黄素的样品中姜黄素含量的测定.  相似文献   

3.
采用三氟化硼-甲醇为衍生化试剂,以HP-FFAP毛细管柱为分离柱,建立了培氟沙星的气相色谱分析法.培氟沙星在质量浓度1.0 mg/L~250.0 mg/L内,药物与内标物峰面积比和药物浓度呈良好的线性关系,检出限为10 μg/L.该方法前处理步骤简单,处理后杂质干扰少,灵敏度高,适用性强,用于药物制剂和体液中培氟沙星含量的测定,平均回收率为93.75%~102.73%,日间RSD均小于2.85%(n=5).  相似文献   

4.
建立了一种高效毛细管电泳方法,用于缬沙坦和苯磺酸氨氯地平的同时分析:以30mmol/L磷酸钠缓冲液(pH=7.47)作为电解质溶液,检测波长237nm,分离电压15kV,高度差进样10s.同时进行了方法学验证:缬沙坦在0.050 4~0.504 0mg/mL内线性良好(r=0.999 8,n=6),迁移时间和峰面积的相对标准偏差(RSD)分别为0.3%和1.3%(n=6),回收率为98.98%~99.79%;苯磺酸氨氯地平在0.050 4~0.504 0mg/mL内线性良好(r=0.999 6,n=6),迁移时间和峰面积的RSD为0.6%和1.4%(n=6),回收率为98.22%~99.46%.通过上述高效毛细管电泳法,缬沙坦和苯磺酸氨氯地平在15.0min内分离良好,分离度(R=29.8).此方法快速,灵敏,实用.  相似文献   

5.
HPLC法测定不同产地山茱萸中熊果酸的含量   总被引:2,自引:0,他引:2  
李倩  魏悦  陈玲 《河南科学》2010,28(6):681-683
为测定不同产地山茱萸中熊果酸的含量,以控制山茱萸的质量,采用SunfireC1(8250mm×4.6mm,0.5μm)色谱柱,以甲醇-水(体积比90∶10)为流动相,流速为1mL/min,在波长210nm处进行检测.实验结果表明,熊果酸在进样量为0.107~1.284μg范围内,峰面积和质量浓度呈良好的线性关系(R=0.9997);平均回收率为100.18%;RSD=1.68%(n=6).该法准确,灵敏度高,重复性好,适用于对山茱萸的质量进行控制.  相似文献   

6.
目的:对清脑复神液的质量标准进行再评价研究,以完善其质量标准.方法:在原标准基础上增加了葛根、枳壳、赤芍的薄层色谱鉴别,同时以盐酸小檗碱、芦丁为对照品建立了小檗碱、总黄酮的含量测定方法.结果:葛根、枳壳、赤芍定性鉴别的专属性强;盐酸小檗碱在0.06~0.96μg范围内与峰面积呈现良好的线性关系(R2=0.999),芦丁在6.00~30.01μg范围内,浓度与吸光度线性关系良好(R2=0.999),平均回收率为101.24%、99.99%,RSD为1.48%(n=6)、1.74%(n=6).结论:清脑复神液现行质量标准可控性不强,经本研究所修订后的标准可增强产品质量的可控性.  相似文献   

7.
采用RP-HPLC法测定发酵液中交沙霉素的含量.以C18为固定相;以甲醇-0.02 mol/L KH2PO4溶液(80∶20)为流动相,用1 mol/L的磷酸调节pH值为3,检测波长232 nm,在进样10μL、交沙霉素含量为31.25~800μg/mL范围内,交沙霉素峰面积与浓度呈良好的线性关系(r=0.9966),测试样品(n=6)RSD为0.45%,平均回收率为99.18%(n=6),RSD=0.49%.在该色谱条件下,采用RP-HPLC法能将交沙霉素与发酵液中的杂质组分实现良好分离.  相似文献   

8.
采用Agilent DB-624毛细管柱色谱柱,FID检测器,DMF为溶剂,建立了顶空气相色谱法同时测定琥珀酸索非利新原料药中乙醇、丙酮、乙酸乙酯、异丙醚、二氯甲烷、甲苯6种残留溶剂的分析方法.结果显示,6种残留溶剂在各自的浓度范围内呈现良好的线性关系(分别为r=0.9997~0.9999,n=6),最低检出限范围为0.147~0.871μg;平均添加回收率为98.64%~101.79%(RSD为0.26%~1.58%,n=3).方法简单、灵敏、可靠,适用于琥珀酸索非利新原料药中残留溶剂的分析检测.  相似文献   

9.
建立顶空气相色谱法测定盐酸安舒法辛原料药中甲醇、乙醇、苯、三乙胺和甲基异丁基酮(MIBK)残留量的方法.以二甲基亚砜(DMSO)和15%氢氧化钠水溶液(3∶1)为溶剂,Agilent DB-1(50 m×0.53 mm,5.0μm)为毛细管色谱柱,氢火焰离子化检测器(FID),柱温采用程序升温.5种残留溶剂峰完全分离(R1.5),在所考察的浓度范围内具有良好的线性,相关系数在0.999(n=8)以上,平均回收率为99.3%~103.5%(RSD=0.3%~2.9%,n=9).本方法定量准确,重现性好,灵敏度高,适用于盐酸安舒法辛原料药中残留溶剂的测定.  相似文献   

10.
建立了用核磁共振内标法快速、准确地测定覆盆子酮对照品含量的方法。采用Bruker公司400 MHz核磁共振仪,在以氘代DMSO为溶剂、苯甲酸为内标、测定温度25℃和扫描32次条件下采集覆盆子酮和苯甲酸混合物的核磁共振氢谱。以覆盆子酮中化学位移在δ6.97和苯甲酸中化学位移在δ7.95的质子信号峰为定量峰,其峰面积比y(As/Ar)与其质量比x(ms/mr)的线性回归方程为y=0.197x+0.783,相关系数r=0.997 0,含量测定重复性实验的RSD值为0.47%(n=6),稳定性的RSD值为0.58%,加样回收率的RSD值为1.18%。测得3批覆盆子酮的质量分数分别为99.53%,99.46%和99.49%。结果表明,在没有对照品的情况下,核磁共振内标法测得对照品的质量分数略低于HPLC的面积归一化法,可用于覆盆子酮对照品的含量测定和质量控制,同时也能够为其他化学对照品的含量测定提供参考。  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.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  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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