有机液态氢化物电催化加氢产物的分析方法

为建立一种对有机液态氢化物电催化加氢产物进行分析的方法,对一系列玻璃管填充柱和毛细管柱进行了筛选,考察了柱温、载气流速、进样器温度、检测室温度等条件对色谱柱分离效果的影响,建立了苯系电催化加氢产物气相色谱分离方法。其优选条件如下：色谱柱为50m长的毛细管柱,其内径为0.25mm,固定液为SP2100;柱温为50℃,进样器温度为150℃,检测室温度为180℃,柱前压为0.2MPa(载气流速为25.1mL/min)。该分析方法具有分析时间短、易控制等优点。     

气相色谱法测定正辛醇氧化产物

本文着重讨论气相色谱法测定正辛醇氧化油相产物。实验结果表明,使用102担体涂5%聚乙二醇—12000固定液的色谱柱,SP—2305型气相色谱仪,双柱双气路四臂铼钨丝热导池检测器,氢气做载气,在柱温150℃左右,检测室温度200℃,汽化室温度220℃,载气流速65—75ml/min,桥流150mA,柱前压力1.3公斤/厘米~2的操作条件下,对正辛醇氧化产物(油相)进行分析,采用已知物对照法和保留指数法定性,内标法定量,结果令人满意。     

气相色谱法同时测定西洋参药材根中12种农药残留的含量

目的：建立西洋参药材根中12种农药残留的分离测定方法．方法：采用气相色谱法,HP-608弹性石英毛细管柱,ECD检测器,柱温起始温度150℃,以5℃／min速度升温,至230℃,保温5min;进样器温度240℃,检测器温度250℃,载气为高纯氮,柱流速20mL／min,层吹流速40mL／min,用外标法计算农药残留的含量．结果：12种农药的峰面积和质量浓度（mg／L）在测定范围内均具有良好的线性关系,精密度良好,平均回收率为94．1％～99．4％．结论：所用方法简单准确,灵敏度高,适用于西洋参药材根中12种农药残留含量的同时测定．     

毛细管气相色谱法在产腈水解酶菌株筛选中的应用研究

利用毛细管气相色谱法对发酵转化液中丙烯酸浓度的测定进行了系统研究,考察了pH值、萃取剂及萃取条件等因素对检测体系的影响,建立了毛细管气相色谱法分析产腈水解酶菌株筛选体系中丙烯酸浓度的分析方法.色谱条件为:30 m×0.32 mm i. d.,膜厚0.25 μm,PEG-20M固定液,氢焰检测器,熔融石英毛细管柱,柱温为程序升温,初始温度100 ℃,保留1 min后以70 ℃ /min升到200 ℃.检测器温度为230 ℃,汽化室温度为210 ℃,载气(N2)的流速为7.6 mL/min.该方法检测丙烯酸和丙烯腈的相对标准偏差(RSD)(n=5 )分别为0.79%,1.21%.平均回收率(n=5 ) 分别为99.83%,100.38%.该方法操作简便,能准确测定转化体系中产物丙烯酸和底物丙烯腈的含量.     

草酰胺类农药在粮食(大豆、玉米)中残留量提取溶剂和洗脱剂的选择

正1色谱条件的选择1.1载气流速。载气的种类主要影响检测器的灵敏度,不同的检测器选用不同的载气,有助于提高检测灵敏度,改善分离效果。本实验使用氮气作为氢火焰离子化检测器的载气,有利于提高灵敏度。通过毛细管柱的载气流量要根据毛细管柱的柱长、柱径膜厚以及被分析物的组成等综合因素设定。高流速虽然可以提高分析效率,但有时可能会因被测物与固定相之间交换不充分而降低柱效。因此,在实际分析中,流速的设定应在满足分离的     

气相色谱法测定小儿奇应丸中冰片的含量

建立气相色谱测定小儿奇应丸中冰片含量的方法.毛细管气相色谱柱为DB-WAX毛细管柱(30 m×0.32 mm×0.25μm),色谱柱温度为140℃,进样口温度为200℃,检测器温度为200℃,载气为氮气,分流比为50∶1,流量为1.0 m L·min~(-1).在该实验条件下,样品中的冰片能很好的分离,冰片在0.02~1.8μg范围内成良好的线性关系(r2=0.998 5,n=11),加样回收率为99.78%(RSD=0.93%,n=6).该方法操作简便,灵敏度高,准确度好,可为小儿奇应丸的质量标准提供理论依据.     

气相色谱-质谱法分析环己酮氨肟化体系中失活催化剂上可溶性沉积物的组成

利用气相色谱-质谱(GC-MS)联用技术,对环己酮氨肟化体系中失活催化剂上的可溶性沉积物进行了分析.分析液样品的制备采用了HF溶解-乙醚萃取法.GC条件:HP-5型石英毛细管色谱柱(30 m× 0.25 mm×0.25μm),载气为He,流速为0.8 mL/min;柱箱程序升温,初始温度为40℃,以20℃/min升至2...     

毛细管柱色谱法测定食品防腐剂山梨酸和苯甲酸的探讨

该文采用AT.食品添加剂分析专用毛细管柱(30m×0.53mm×1.00 μ m),对山梨酸和苯甲酸两种常见防腐剂进行测定,实验表明,通过对色谱条件的优化,在柱温190℃,载气流速160kPa条件下,在3.5min内实现基线分离,各组分分离良好,分析速度快,准确度高,山梨酸回收率为88.04％～94.71％,RSD≤4.3％;苯甲酸回收率为94.02％～104.47％,RSD≤1.4％.     

GC法测定他达拉非残留溶剂

采用气相色谱法及残留溶剂测定法对他达拉非的残留溶剂进行测定.用6％氰丙基苯基-94％二甲基聚硅氧烷为固定液的毛细管柱为色谱柱;柱温在50℃保持5min,再以30℃/min的速率升至240℃,维持5min;检测器为氢火焰离子化检测器,检测器温度为260℃,进样口温度为220℃,载气流速3.0 mL/min,分流比10:1;进样体积1μL,记录色谱图.本方法可以有效、准确地检测出他达拉非的残留溶剂.     

毛细管气相色谱法测定白芍中有机氯农药的含量

在建立白芍中七氯、环氧七氯及滴滴涕异构体含量的气相色谱分析方法中,样品以石油醚加丙酮在索氏提取器中提取,提取液以浓硫酸净化;采用DB-5(30 m×0.25 mm×0.25μm)弹性石英毛细管柱分离样品;以GC-ECD检测农药七氯、环氧七氯及滴滴涕的含量(色谱条件:载气为N2(99.999%,1.5 mL/min);分流比为2.3∶1;进样器温度为200℃,检测器测试为330℃,柱升温程序是从100℃(保持0.5 min)开始以15℃/min升至200℃保持1.0 min),再以4℃/min升至240℃(保持7 min);方法的加标平均回收率为96.27%~100.3%,精密度为2.0%~6.9%。     

Markedness and its Interpretation in Language Use

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.     

Features of Women's language

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

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-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

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