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1.
Finnigan Mat 4515色/质联用仪真空系统的维护与维修   总被引:1,自引:1,他引:0  
叙述大型精密仪器Finnigan Mat4515色/质联用仪的真空系统的维护与维修,利用报废的旧仪器零部件,在技术上稍加改动,便可修复即将报废的色/质联用仪,使其继续发挥作用,为科研工作赢得了时间.投资少,见效快,事半功倍,具有一定的经济和社会效益,是维修旧的大型仪器的有效途径.  相似文献   

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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   

3.
公开号:CN202693539U公开日:2013.01.23申请人:苏州圣苏新药开发有限公司本实用新型公开了一种药物分析用液质联用仪的降温装置,包括水箱、连接管、潜水泵、表冷器、电磁阀、  相似文献   

4.
通过圆盘膜萃取提取河水中多环芳烃、多氯联苯,肽酸酯等半挥发有机物,并用气质联用仪及选择离子(SIM)进行样品定量分析,加标回收率在70%~130%之间,测定检出限达到pg/mL级(10-12)水平.  相似文献   

5.
报道了调味品中氯丙醇的衍生化气相色谱(GC/ECD)和衍生化气相色谱双串联质谱法(GC/MS/MS)测定。GC/ECD测定酱油中3—氯—1,2—丙二醇(3—MCPD)的检出限达到0.01mg/kg,回收率为91%~104%,变异系数为2.27%~7.96%;GC/MS/MS同时测定酱油中1,3—二氯—2—丙醇、2,3—二氯—1—丙醇和3—氯—1,2—丙二醇,1,3—二氯—2—丙醇、2,3—二氯—1—丙醇的检出限为0.02mg/kg,3—氯—1,2—丙二醇的检出限为0.01mg/kg,回收率在92%~106%,变异系数为3.51%~13.33%。  相似文献   

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A simple and sensitive gas chromatography/tandem mass spectrometry (GC/MS/MS) method is described for the detection of anabolic steroids, usually found in keratin matrix at very low concentrations. Hair samples from seven athletes who spontaneously reported their abuse of anabolic steroids, and in a single case cocaine, were analyzed for methyltestosterone, nandrolone, boldenone, fluoxymesterolone, cocaine and its metabolite benzoylecgonine. Anabolic steroids were determinate by digestion of hair samples in 1 m NaOH for 15 min at 95 degrees C. After cooling, samples were purificated by solid-phase and liquid-liquid extraction, then anabolic steroids were converted to their trimethylsilyl derivative and finally analyzed by GC/MS/MS. For detection of cocaine and benzoylecgonine, hair samples were extracted with methanol in an ultrasonic bath for 2 h at 56 degrees C then overnight in a thermostatic bath at the same temperature. After the incubation, methanol was evaporated to dryness, and benzoylecgonine was converted to its trimethylsilyl derivative prior of GC/MS/MS analysis. Results obtained are in agreement with the athletes' reports, confirming that hair is a valid biological matrix to establish long-term intake of drugs.  相似文献   

10.
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   

11.
The determination of Dinocap, one of the most often used acaricides and contact fungicides, is complicated by the fact that it consists of several isomeric alkyldinitro-phenyl-crotonates. In a first step, GC/IR and GC/MS has been used to separate the mixture, to determine the chromatographic behaviour and to fully characterize the six different isomeric compounds. The structures of additional impurities in the commerical preparation were shown to be the correlating phenols. An extraction/preconcentration method has been devised based on Carbopack B, yielding recoveries between 75 and 98%. A qualified estimation of the total Dinocap content of drinking water can be made by this approach for concentrations well below the limits set by the European drinking water regulations. The development of a complete analytical procedure based on these results appears to be feasible.Dedicated to Professor Dr. Dr. h.c. mult J. F. K. Huber on the occasion of his 70th birthday  相似文献   

12.
Summary 100 mg amounts of glue on two copper-age arrowheads have been investigated by means of gas-chromatography/mass spectrometry and chemometrics. The samples have been identified as birch bark derivatives, but the distribution patterns of triterpenoids and steroids show significant differences to similar samples from younger archaeological periods that can be explained by the use of a different species of birch and a different method of preparation.  相似文献   

13.
乙酰乙酸乙酯烯醇式与酮式GC/MS和GC/IR分析   总被引:1,自引:0,他引:1  
采用GC/MS对乙酸乙酯烯醇式在不同离子源温度,接口温度,进样器温度,柱温等条件下的气相色谱行为进行了研究,用重氢交换法和高分辨质谱法对烯醇式和酮式的质谱进行了解析,并通过GC/IR研究了烯醇式和酮式的红外光谱。  相似文献   

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