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向同寿 《分析测试技术与仪器》1994,(3):18-21
随着我国石油工业的发展和色质联用仪广泛应用,生物标志化合物的鉴定与研究越来越重要。由于目前缺少完整的和系统的生物标志物数据资料.研究人员往往要花费大量的时间寻查文献,许多化合物无法鉴定,本谱库针对有机地球化学家们鉴定生物标志物的迫切需要以及弥补现有商业质谱数据库的不足,作者长期积累和广泛收集各类生物标志物的质谱数据文献,建立了有机地球化学研究工作中各类生物标志物的质谱库。该库提供化合物名称、分子式、分子峰、基峰、质谱强度等。 相似文献
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近年来,随着材料科学领域的发展,机械性能优异且具有特定功能的有机-无机复合材料成为了研究热点。而天然的生物矿化过程产生了在自然界中分布广泛、结构特征多样性、机械性能优异的天然生物矿物,比如牙齿、骨骼、珍珠、贝壳、海胆刺、海洋红虫颚等。这些天然复合增强材料中的矿化组织结构特点和矿化机理为仿生设计与合成具有特定结构、特定功能和优异机械性能的材料提供了理论依据。通过模拟天然过程的仿生矿化方法,利用有机基质调控无机矿物成核生长为固态矿物,最终能够定向组装具有特定有序结构和先进功能的有机-无机复合材料。本文主要综述了自然界中通过生物矿化过程得到的高强度、高韧性的天然复合增强材料,以及受生物矿化增强现象的启发,在化学与材料仿生矿化合成中出现的一些有机-无机复合的增强材料。 相似文献
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用加氢热解(hydropyrolysis)释放高演化源岩干酪根和沥青分子网络中共价键结合的生物标志物,在恢复原始有机地球化学信息方面具有重要的意义,可应用于源岩有机质生源确定、成熟度确定、古沉积环境判识以及油/源对比等.实验表明,样品沥青“A“与加氢热解产物中生物标志物的组成存在一定的差异,加氢热解产物中含有丰富的地球化学信息.加氢热解具有产物收率高、结构重排少、生物特征保持完整等特点,能够合理地释放出沉积有机质分子骨架中具有原生性的组分,保持完整的原始生物标志物结构和立体化学特征.加氢热解技术为油气地球化学研究开辟了新途径. 相似文献
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王美珠 《广东微量元素科学》1996,3(7):69-71
微量元素生物地球化学研究进展──第三届国际微量元素生物地球化学会议简介王美珠(浙江农业大学硒素研究室,杭州310029)1995年5月15日~19日,笔者出席了在法国巴黎召开的第三届国际微量元素生物地球化学会。会议由法国环境部主办。参加这次大会的有来... 相似文献
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金属有机骨架(metal-organic frameworks, MOFs)材料因具有稳定的骨架结构、可调的孔尺度和大的比表面积等优良特性,被作为固定生物探针的基体,用于构建电化学生物传感器.电化学生物传感器是一种以电极为信号转换器,通过敏感元件,将肿瘤标志物的高特异性与电化学传感器的高灵敏度相结合的检测装置,在临床癌症筛查方面具有重大应用.本文概述了金属有机骨架复合材料的分类,总结了过去五年基于有机金属骨架材料的电化学生物传感器在检测作为癌症早期诊断指标的各种标志物(如癌症标志物、microRNA和DNA)方面的进展,并对其未来发展进行了展望. 相似文献
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现代仪器分析技术在天然生物复合材料研究中具有十分重要的地位.人们对生物矿化的了解,从简单的有机/无机相间的叠层结构到复杂的多级构造、从晶粒的有序排列到特定的晶面取向、从定性描述可溶性有机基质(SM)和不可溶性有机框架(IM)到基质氨基酸分子的组分和蛋白质序列片段的解析、从有机/无机界面天然有机模板对无机结构的指导作用到人工组装的有机模板对诱导产物进行调控,尤其进入到分子水平,无不借助于分析测试技术的进步. 相似文献
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环境样品中的有机污染物种类繁多、结构复杂、含量不等,对其进行分析测试难度很大。近年来,采用气相色谱-质谱联机、气相色谱-红外(GC-IR)联机、液相色谱-质谱(LC-MS)联机以及超临界色谱-质谱联机(SFC-MS)等新技术,已对许多环境样品中的复杂有机污染物获得了高灵敏度和高选择性的定性、定量分析结果,包括有机污染物的结构信息。本文采用超细玻璃纤维滤膜采样,热脱附仪和气相色谱-质谱联用分析了大气颗粒物中的半挥发性有机污染物,与传统的索氏提取法进行了对比。 相似文献
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采用经典柱色谱法对煤液化循环油和“加氢”后的循环油进行族组成分离,将其分离成饱和烃、芳香烃和极性物3个组分,并用核磁共振波谱仪对各个组分进行定性分析,同时用气质联用分析方法初步确定了饱和烃和芳香烃两个馏分的主要物质组成。结果表明:循环油饱和烃部分主要由C12~C27直链烷烃组成,芳香烃部分主要组成是烷基取代的氢化单环芳烃及少量的多环芳烃。而循环油经420℃“加氢”后饱和烃部分除了含C12~C27的直链烷烃,还有一些直链烷烃的异构体和环烷烃,芳香烃部分主要是双环、三环、四环芳烃,单环芳烃则完全消失。 相似文献
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J. M. Letoffe C. Sigala R. Chiriac C. Dutheil J. Carre 《Journal of Thermal Analysis and Calorimetry》2004,76(2):491-505
A thermogravimetry (TG) - gas chromatography (GC) - mass spectrometry (MS) coupling has been developed in order to analyse
complex gaseous mixtures which are evolved during degradation process of materials. A self-contained interface has been built
and tested with different compounds as hydrocarbon products, copolymers and gaseous mixtures from urban landfill.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Modification of commercial LC/MS instrumentation to allow both atmospheric pressure (AP) LC/MS and GC/MS is described. Advantages of this additional capability versus LC/MS alone include higher chromatographic resolution in the GC versus LC mode, greater peak capacity for complex mixture analysis, higher sensitivity for a variety of volatile compounds, and the ability to observe compounds of low polarity that are not readily observed in LC/MS. Advantages over conventional GC/MS include the ability to use higher carrier gas flow and shorter columns for passing less volatile materials through the gas chromatograph, selective ionization, and rapid switching between positive and negative ion modes. Other advantages include application of the enhanced capabilities of LC/MS instrumentation to GC/MS analyses such as cone voltage fragmentation, MS(n), high mass resolution, and accurate mass measurement. Limitations of APGC/MS include the inability to observe saturated hydrocarbon and certain other highly nonpolar compounds and less odd-electron fragmentation for computer aided library searching. For some analyses, the limitation related to ionization of highly nonpolar compounds is advantageous, as is the simplified mass spectrum and easy molecular weight identification that results from less fragmentation observed in the AP ionization mode. 相似文献
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Tm/Ts,C29甾烷ααα20S/(20S+20R)是判断原油成熟度的重要参数。所以能否准确地检测这些化合物就显得尤为关键和重要。以往我们通常采用GC-MS单极质谱来检测原油和烃原岩抽提物中饱和烃里的萜烷和甾烷成分。但利用GC-MS单极质谱分析得到的m/z191质量色谱图中,Tm、Ts往往与三环和四环萜烷同时共流出,以至有时导致假的Tm/Ts比值。利用GC-MS单极质谱分析得到的m/z217质量色谱图中规则甾烷分布受重排甾烷的影响,很难区分C29甾烷和4-甲基甾烷(即没有办法排除共流峰的干扰)。这是因为Tm、Ts和C29甾烷等生物标记化合物在特定的色谱柱中有 相似文献
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GC/MS法研究焦炉烟气中多环芳烃类污染物 总被引:1,自引:0,他引:1
焦炉烟气中的有机污染物种类繁多 ,但是对人类和生态环境有严重危害的主要是多环芳烃类化合物 [1~ 3] .由于该类化合物结构复杂 ,含量不等 ,因此 ,对其进行分析测试难度很大 .近年来 ,采用色谱 /质谱 (GC/ MS)联机、色谱 /红外 (GC/IR)联机、液相色谱 /质谱联机 (LC/ MS)以及超临界色谱 /质谱联机 (SFC/ MS)等新技术 ,对环境中的多环芳烃类化合物取得了高灵敏度和高选择性的定量分析结果 ,并获得了许多结构信息 .但在我国 ,只对个别地区进行了研究 [4~ 6] ,目前还难以普遍实现 .本文利用气相色谱 /质谱联用法 ,对鞍山钢铁公司炼焦… 相似文献
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《Arabian Journal of Chemistry》2020,13(7):6256-6266
Volatile oils from flowers and leaves of C. creticus L. and C. salviifolius L. were extracted by two extraction methods; namely, hydrodistillation and solid-phase micro-extraction (SPME). The chemical composition of essential oils was analyzed by GC and GC–MS. The volatile extracted from leaves and flowers of C. criticus using SPME was dominated by monoterpenes and sesquiterpenes hydrocarbon with α-pinene, camphene and α-cubebene as major components. In hydrodistillation, the oil extracted from leaves was dominated by oxygenated diterpenes and diterpenes hydrocarbon with manoyl oxide and sclarene as major components, whereas, the oil extracted from flowers was dominated by oxygenated diterpenes and diterpenes hydrocarbon with manoyl oxide and abietatriene as major components. The volatile from flowers and leaves of C. salviifolius obtained by SPME were dominated by monoterpenes and sesquiterpenes with δ-3-carene, α-pinene, β-pinene, and E-caryophyllene as major constituents. On the other hand, the oils from flowers and leaves of C. salviifolius obtained by hydrodistillation were dominated by oxygenated diterpenes, diterpenes hydrocarbon and esters with dehydro abietol, abietol, manoyl oxide and methyl octadecenoate as major components. In the leaves, the major components of the oil were manoyl oxide, E-ethyl cinnamate, and Z-ethyl cinnamate. These oils showed weak antioxidant activity when compared to the positive controls α-tocopherol, ascorbic acid, and EDTA, while the crude extracts aq. MeOH, butanol, and water showed good antioxidant activity. Discriminating between the studied plants based on the extraction method was also possible upon applying Principle component analysis (PCA) to the obtained GC–MS data. 相似文献
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Mass spectrometric techniques for characterizing low-molecular-weight resins used as paint varnishes
I. Bonaduce M. P. Colombini I. Degano F. Di Girolamo J. La Nasa F. Modugno S. Orsini 《Analytical and bioanalytical chemistry》2013,405(2-3):1047-1065
The molecular structure of three low-molecular-weight resins used as paint varnishes has been characterized by use of an approach based on three different mass spectrometric techniques. We investigated the ketone resin MS2A, the aldehyde resin Laropal A81, and the hydrocarbon resin Regalrez 1094, now commonly used in restoration. To date, the molecular structures of these resins have not been completely elucidated. To improve current knowledge of the chemical composition of these materials, information obtained by gas chromatography–mass spectrometry (GC/MS), pyrolysis–gas chromatography–mass spectrometry (Py/GC/MS), and electrospray ionization mass spectrometry (ESI–Q–ToF) was combined. Analysis, in solution, of the whole polymeric fraction of the resins by flow-injection ESI–Q–ToF, and of the non-polymeric fraction by GC–MS, enabled us to identify previously unreported features of the polymer structures. In addition, the Py–GC/MS profiles that we obtained will help to enhance the databases currently available in the literature. The proposed approach can be extended to other low-molecular-weight resins used as varnishes in conservation. 相似文献