气相色谱-冲火焰光度法分析催化裂化汽油中的硫化物

对采自中国石油大学胜华炼油厂的催化裂化主精馏塔的催化裂化（FCC）粗汽油进行了实沸点切割,采用气相色谱-脉冲式火焰发光检测器（GC-PFPD）联用技术和外标法定量测定了各窄馏分的硫含量和硫化物类型分布,并与微库仑法和X荧光法进行了对比。研究结果表明脉冲火焰光度（PFPD）检测器具有较高的灵敏度和选择性,在测量范围内对不同硫化物的响应具有很好的线性和一致性,同时定性简单、定量准确,是分析汽油中总硫含量的理想检测器;FCC汽油中的硫含量在（110～160）℃馏程范围内含量最高（大干1500μg／mL）;主要的硫化物为二硫化碳、噻吩、2-甲基噻吩、四氢噻吩、2,4-二甲基噻吩、2,3-二甲基噻吩、3,4-二甲基噻吩、C3-噻吩、C4-噻吩,以噻吩类尤其是二甲基噻吩含量最高。     

人参脂肪酸和挥发油成分的GC-MS分析

利用索氏提取法和水蒸气蒸馏法提取人参根中的脂肪酸和挥发油成分,采用气相色谱-质谱(GC-MS)联用技术,分别鉴定了脂肪酸中的19个化合物和挥发油中的46个化合物,运用气相色谱峰面积归一化法确定了它们的相对百分含量,脂肪酸中主要是亚油酸和油酸等不饱和脂肪酸,挥发油中含量较高的是2,2’-亚甲基双[6-(1,1-二甲基乙基)-4-甲基苯酚](10.56%)、1,2-苯二羧酸二异辛酯(6.52%)、7,11-二甲基-3-亚甲基-1,6,10-十二碳三烯(5.45%)和乙酸-13-十四碳烯-1-酯(4.14%).     

鄢陵腊梅香气成分的固相微萃取-气质联用分析

采用顶空固相微萃取(SPME)吸附采集鄢陵腊梅花的香气成分,通过气相色谱-质谱联用(GC-MS)分析鉴定,以GC-MS总离子流色谱峰的峰面积归一化定量分析鄢陵腊梅花的香气成分,鉴定出含有芳樟醇、乙酸苄酯、吲哚、苯甲醇、反乙位罗勒烯、壬醛、丁香酚、桂醇和甲琥胺等60种挥发性物质.结果表明,固相微萃取-气相色谱-质谱(SPME-GC-MS)法是一种简单、可靠、适用于鲜花香气成分分析的方法.     

丙烯中微量硫化物的定性分析

采用气相色谱-脉冲火焰光度检测器(GC-PFPD)与气相色谱-质谱(G-C-MS)联用技术,分析研究炼油厂精制丙烯原料中的微量硫化物.通过对原料丙烯中的微量硫化物进行富集,采用GC-MS技术与标准品定性,首次从丙烯中检测到异丙基二硫醚和异丙基三硫醚.     

用于药物分析的几种新方法与新技术

介绍用于药物分析的几种色谱或波谱分析新方法与技术,包括手性HPLC拆分法、毛细管电泳分析法、毛细管气相色谱分析法、近红外分光光度法、核磁共振光谱分析法、X射线粉末衍射法、液相色谱-质谱联用技术、液相色谱-核磁共振联用技术、气相色谱-红外光谱联用技术、气相色谱-质谱联用技术.旨在对有关研究工作者提供参考.     

气相色谱-质谱联用技术在天然药物中的应用

综述近年来气相色谱-质谱(GC-MS)联用技术在天然药物分析中的应用.GC-MS联用已广泛应用于天然药物多个研究领域,其在天然药物分析,品质保证研究发展中占重要地位.     

研究生气相色谱-质谱联用实验课程教学体会

结合气相色谱-质谱实验课程教学的实际情况,阐述了气相色谱-质谱联用实验教学的作用和意义;探讨了在实验过程中如何有效地提高学生的兴趣,加强实践操作能力,切实地提高教学质量。     

液相色谱-质谱联用(LC-MS)技术应用研究

液相色谱-质谱联用(LC-MS)技术是一项既可定性又可定量检测的较完美的、应用范围广、与传统分离分析方法相比具有独特优势的技术。本文在综合近年来有关文献的基础上系统地阐述了液相色谱-质谱联用(LC-MS)技术及其在食品、医药、饲料、化学化工等领域的应用进展,以期为在生产和科研中进一步发挥此技术的独特优势而提供理论参考。     

小果十大功劳挥发油的化学成分分析

用水蒸气蒸馏法提取小果十大功劳(Mahonia bodinieri Gagnep.)枝叶的挥发油后,通过气相色谱-质谱联用(GC-MS)法鉴定化学成分,并以气相色谱法确认主要成分。从小果十大功劳挥发油中共分离出50多个组分,鉴定了其中36个化合物,占总量的90%以上。小果十大功劳挥发油的主要成分为主要成分为棕榈酸(54.49%),含量较高的还有亚油酸(5.98%)、α-金合欢烯(5.51%)、亚麻酸甲酯(3.45%)、棕榈酸甲酯(3.36%)等。     

花梨木挥发性化学成分GC-MS分析研究

采用水蒸气蒸馏法加醋酸乙酯从花梨木木屑中提取挥发性成分,利用气相色谱-质谱联用技术对挥发性化学成分进行分析鉴定,确认出其中的30种成分,占色谱总馏出峰面积的90%以上。结果显示花梨木挥发性主要化学成分为β-桉叶醇,α-乙酸松油酯,2,6-二叔丁基对甲酚,2-甲基苯并呋喃,3-(1-甲酰-3,4-亚甲二氧基)-苯甲酸甲酯等化合物。     

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.     

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.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

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