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1.
本文通过高效液相色谱ODS柱效的测定研究结果,表明溶质、流动相、流速、温度、进样量、进样体积以及半峰宽的测量工具等因素对柱效的测定都有不同程度的影响。因此,对于所测定的柱效,必须附上有关的实验条件,而不能够笼统地称某一填料或某一色谱柱的柱效多少。  相似文献   

2.
对7种烷基取代酚类化合物在反相高效液相色谱固定相ODS柱,键合-CN基柱上,用甲醇、乙腈,水为流动相体系,选用几种常用的溶质溶剂,考察溶质的色谱保留行为,结合现有的几种键合反相液相色谱保留机理,提出了保留行为模型,对不同的溶质溶剂造成溶质的色谱峰型产生裂分拖尾,前延或不保留等现象给予了较满意的解释。  相似文献   

3.
对7种烷基取代酚类化合物在反相高效液相色谱固定相ODS柱、键合-CN基柱上,用甲醇、乙腈、水为流动相体系,选用几种常用的溶质溶剂,考察溶质的色谱保留行为,结合现有的几种键合反相液相色谱保留机理,提出了保留行为模型,对不同的溶质溶剂造成溶质的色谱峰型产生裂分拖尾、前延或不保留等现象给予了较满意的解释.  相似文献   

4.
农药复配剂中阿维菌素含量反相液相色谱法测定法的研究   总被引:1,自引:0,他引:1  
本研究采用反相液相色谱对混剂产品中的阿维菌素含量进行测定。色谱分析所采用的条件是 :HPHypersil ODS C18反相柱 ,流动相为甲醇 -水 (9:1) ,流速为 0 .8ml/ min,进样量为 10 ul,柱温 2 5℃。测定了阿维菌素标准品活性成分在色谱柱上的保留时间、峰高、峰面积 ,其中 B1a保留时间为 7.0 5 min,B1B为 6 .2 min。其浓度和色谱峰面积呈线性相关 y=0 .0 4 0 5 x- 0 .16 41(r=0 .9998)。方法回收率 93.5 % - 10 2 .5 % ,变异系数0 .32 % - 0 .71% ,表明方法准确可靠。最终测得样品中的阿维菌素 B1a含量为 0 .0 77%。  相似文献   

5.
目的 建立一个新的描述溶质在二元流动相液相色谱体系中保留的三参数方程并以实验进行验证。方法 通过研究液相色谱体系中溶质分子和溶剂或稀释剂分子的相互作用,得到一个溶质在液相色谱体系中保留的三参数方程,并用不同极性的溶质分子的甲醇-水、乙腈-水和四氢呋喃-水反相色谱体系和极低流动相浓度下的正相色谱体系对此方程进行了验证。结果 在全浓度流动相范围内,实验数据均能用此方程良好描述,且保留方程中的3个参数与所研究的色谱体系的特征紧密相关。结论 所提出三参数溶质保留方程可以用来良好描述二元流动相液相色谱体系中溶质保留的实验结果。  相似文献   

6.
本文介绍在日本岛津Lc-6 A高效液相色谱仅所配C-R 3A数据处理装置上编制了一个绘图程序.运用此程序可在CRT屏幕上绘制色谱图,在各色谱峰峰顶自动打印保留时间.计算报告中还将显示峰号、保留时间、半峰宽、峰面积、峰高、百分浓度,屏上还设置记时器自动记时.  相似文献   

7.
建立了煤软沥青庚烷萃取物的HPLC检测方法.探讨了煤软沥青庚烷萃取物的HPLC最佳检测条件:紫外检测器、ODS色谱柱、甲醇与水的体积比为9:1的混合液为流动相.结合紫外光谱确定了庚烷溶物组主要成分在HPLC流出曲线中的出峰顺序.为煤焦油沥青庚烷溶组的检测提供了一种简便、快速的方法.  相似文献   

8.
沥青庚烷萃取物HPLC检测及主要成分的确定   总被引:1,自引:0,他引:1  
建立了煤软沥青庚烷萃取物的HPLC检测方法。探讨了煤软沥青庚烷萃取物的HPLC最佳检测条件:紫外检测器、ODS色谱柱、甲醇与水的体积比为9:1的混合液为流动相。结合紫外光谱确定了庚烷溶物组主要成分在HPLC流出曲线中的出峰顺序。为煤焦油沥青庚烷溶组的检测提供了一种简便、快速的方法。  相似文献   

9.
研究不同开封时间的乙酸铵对糖精钠、山梨酸保留时间的影响。采用高效液相色谱法,以二极管阵列检测器(DAD)检测,色谱柱为Waters Sunfine C18(250mm×4.6mm,5μm),流动相甲醇-乙酸铵溶液(5:95),柱温35℃,用不同时间开封的同一厂家的乙酸铵配置乙酸铵溶液进行试验,糖精钠和山梨酸的相对保留时间和出峰顺序发生改变。不同开封时间的乙酸铵对糖精钠、山梨酸保留时间和出峰顺序有影响,进而影响峰形及峰纯度。  相似文献   

10.
本文将锑酸锌无机离子交换剂填充在色谱柱中,以酒石酸钠、酒石酸和氯化钠为洗脱液体系,采用国产SL-02型离子色谱仪(配备库仑检测器)研究了锌、镉、汞离子的色谱分离行为:探讨了洗脱液浓度及流速对组分保留时间,分高度和理论塔板数的影响因素,并测定了混合试样中汞的含量。  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.
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   

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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