氢火焰离子化检测器故障一例

介绍GC-9790气相色谱仪的氢火焰离子化检测器由于燃烧室高温燃烧氧化作用,极化电极与极化电缆相连接的金属夹变形松动,导致接触电阻增大和间隙放电,使得检测器灵敏度下降并产生大的噪声电压。提出了故障的排除方法。     

气相色谱仪FID检定过程中的常见故障及排除

气相色谱仪氢火焰离子化检测器（FID）检定过程中常见故障为仪器无法正常点火、仪器进样重复性差、仪器基线噪声漂移大,对这些故障原因进行了分析并提出了解决办法。     

气相色谱-红外光谱联机测定石油化工废水中挥发性有机物

１引言 气相色谱一红外光谱（ＧＣ－ＩＲ）联机测定石油化工废水中挥发性有机物,以气相色谱分离,红外定性,氢火焰离子化检测器定量。为提高红外分析灵敏度,水样前处理应用高富集倍数的吹脱捕集技术,并使用大吹脱体积,两级捕集方式;色谱柱采用大口径石英毛细柱,以减小分流,增加进样量。为使用红火焰离子化检测器（ＦＩＤ）定量技术解决剖析分析无标样定量问题,本方法成功地实现了气相色谱一红外光谱－氢火焰离子化检测器联机,使未知物定性定量一次完成。２实验部分２． １仪器 Ｃａｒｌｏ Ｅｒｂａ ５３００气相色谱仪（意大利 Ｃ…     

氢火焰离子化检测器凝集物引发的噪声故障分析

GC-9790型气相色谱仪氢火焰离子化检测器的燃烧室被高沸点凝集物污染,在直流电场作用下,持续发生电离反应,形成约4000μV的基线噪声。对故障原因和故障产生机理进行了分析,提出了故障排除方法。     

热解吸直接进样气相色谱法分析室内空气中的总挥发性有机化合物

建立室内空气中总挥发性有机化合物的热解吸直接进样气相色谱分析方法。采集的空气样品吸附于Tenax吸附管中,将吸附管置于热解吸仪上,解吸气体直接由进样阀快速进入气相色谱仪进行分析,采用非极性石英毛细管柱,氢火焰离子化检测器检测。8种组分的线性范围为0.01～11.04μg,检测限为0.001～0.006μg,测定结果的相对标准偏差RSD≤4.8%。该方法符合室内空气中总挥发性有机化合物分析的要求。     

均相催化气相色谱法分析铅

均相催化气相色谱法用于铜、铁的分析已有报道,但未见用于铅的分析。本文研究了铅对下列反应的催化作用: C_6H_5NH_2+NaNO_2/冰水→C_6H_5N~+=N+NaOH+OH~- 当控制一定条件时,苯腈的色谱响应值与铅的浓度成线性关系。应用于废水中微量铅的分析,结果较满意。 (一)主要仪器与试剂 100型气相色谱仪,氢火焰离子化检测器检测。     

毛细管色谱柱-国产热导检测器系统的改装

正用于气相色谱分析的检测器种类繁多,其中以热导检测器(TCD)、氢火焰离子化检测器(FID)最为常用。但有些物质在氢火焰中基本没有响应,用FID不能解决这些检测问题。所以,在色谱分析工作中对TCD的研究具有重要意义。国产热导型气相色谱仪死体积大,灵敏度相对较低,通常选用填充柱与其使用~([1-4])。随着石英毛细管色谱柱的出现与发展,毛细管色谱柱逐步取代填     

毛细管气相色谱法测定化妆品中的酞酸酯

建立了用毛细管气相色谱配氢火焰离子化检测器测定化妆品中6种酞酸酯(邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二丁酯(DBP)、邻苯二甲酸丁基苄基酯(BBP)、邻苯二甲酸二(2-乙基己)酯(DEHP)和邻苯二甲酸二正辛酯(DOP))的方法。样品用甲醇超声提取,经高速冷冻离心,清液经干燥脱水过0.5 μm滤膜过滤,直接注入气相色谱仪进行分析。然后,经过气相色谱-电子电离-质谱检测分析,确证气相色谱-氢火焰检测的阳性检出结果。用保留时间定性,外标法定量。6种酞酸酯的回收率为82.90%～     

气相色谱法测定广藿香油中百秋李醇含量

建立了气相色谱仪测定广藿香油中百秋李醇含量的方法。用毛细管色谱柱DB-5MS（30m×O．32mm．0．25μm）,正十八烷为内标,氢火焰离子化检测器进行检测,内标法定量。百秋李醇含量在0．2-2．0mg／mL范围内,百秋李醇峰面积和内标物峰面积之比与百秋李醇质量浓度呈良好的线性关系,相关系数r=0．9997。方法的检出限为1μg／mL,加标回收率为90．0％～100．6％,测定结果的相对标准偏差为1．22％（n=6）。研究表明,本法简便、快速、测定结果准确可靠,精密度优于外标法。     

气相色谱法测定太白洋参中的甘露醇含量

介绍了应用气相色谱法－氢火焰离子化检测器检测太白洋参中甘露醇的方法,采用OV－225填充柱分离该法平均回收率为90．66％,检出限为0．1mg/kg。     

On-line multidimensional chromatography using packed capillary liquid chromatography and capillary gas chromatography

The introduction of selected fractions from a liquid chromatograph into a gas chromatograph has been described; however, analyses were performed by off-line experiments requiring collection and reinjection of the separate fractions or by on-line procedures where disadvantageously, only a fraction of the separated peak or a well resolved component in a mixture could be introduced into a gas chromatograph. This disadvantage is overcome by the apparatus and method described in this paper, which utilizes a multidimensional chromatography system employing a high efficiency, packed capillary LC column coupled on-line to a capillary gas chromatograph. The liquid chromatograph (so designed) can act as a highly efficient clean-up or chemical class fractionation step prior to introduction into the gas chromatograph, significantly reducing sample preparation times in many applications. Thus minor components in a complex matrix can be determined without prior sample clean-up, an example of which is the determination of polychlorinated biphenyls in a complex hydrocarbon matrix.     

Analysis of biogenic amines using corona discharge ion mobility spectrometry

A new method based on corona discharge ion mobility spectrometry (CD-IMS) was developed for the analysis of biogenic amines including spermidine, spermine, putrescine, and cadaverine. The ion mobility spectra of the compounds were obtained with and without n-Nonylamine used as the reagent gas. The high proton affinity of n-Nonylamine prevented ion formation from compounds with a proton affinity lower than that of n-Nonylamine and, therefore, enhanced its selectivity. It was also realized that the ion mobility spectrum of n-Nonylamine varied with its concentration. A sample injection port of a gas chromatograph was modified and used as the sample introduction system into the CD-IMS. The detection limits, dynamic ranges, and analytical parameters of the compounds with and without using the reagent gas were obtained. The detection limits and dynamic ranges of the compounds were about 2 ng and 2 orders of magnitude, respectively. The wide dynamic range of CD-IMS originates from the high current of the corona discharge. The results revealed the high capability of the CD-IMS for the analysis of biogenic amines.     

便携式气相色谱仪测定海上平台天然气中氮气含量

为保障海上平台安全生产,采用便携式色谱仪对海上平台天然气中氮气进行分析.便携式色谱仪利用气相色谱原理能够准确分析产出气体组成.仪器检测数据精度高,检测速度快,单个样品检测时间为4 min,可连续工作时间为8 h.现场检测表明便携式色谱仪具有操作简单、快速等特点,对快速判定气体成分显示出一定的优越性,为海上油气田天然气中氮气快速检测提供技术支持.     

裂解气相色谱—裂解毛细柱气相色谱联用仪

设计了一种裂解气相色谱--裂解毛细柱气相色谱联用仪。在第一级裂解气相色谱仪把聚合物裂解并分离裂解产物,分离了的产物用六通气体进样阀选取并逐个在第二级裂解气相色谱仪裂解,得到聚合物裂解产物的裂解气相色谱图。与低分子化合物的标准指纹图比较,这些裂解产物就得到确认,这样,就可以充分肯定地推断复杂聚合物的组成。     

A portable gas chromatograph with air carrier gas for the determination of explosive traces

A three-step scheme for a miniature air purification filter for a gas chromatograph has been proposed. A method for controlling the selectivity of a new ion gas chromatography detector has been considered using a simulating model. The possibility of determining explosive traces by a gas chromatograph with air as a carrier gas has been demonstrated.     

气相色谱—四温裂解气相色谱联用分析

本文利用气相色谱—四温裂解气相色谱联用仪对一些混合物作定性分析,此方法可用来作气相色谱难分离物质的鉴定。     

On-line multidimensional supercritical fluid chromatography/capillary gas chromatography

A new analytical technique combining on-line supercritical fluid chromatography with capillary gas chromatography has been developed. The supercritical fluid sample effluent is decompressed through a restrictor directly into a conventional capillary gas chromatographic injection port. This technique allows for not only direct (100%) sample transfer from the supercritical fluid chromatograph to the gas chromatograph but also for selective or multi-step heartcutting of various sample peaks as they elute from the supercritical fluid chromatograph. Heartcut times are determined by monitoring the responses from the flame ionization or ultraviolet absorbance detectors on the supercritical fluid chromatograph. This report describes the operational setup and provides the results of heartcut reproducibility experiments using normal hydrocarbon and aromatic test mixtures. Results from studies where operational parameters were varied, such as GC injector temperature, will also be provided. The potential usefulness of this new technique for selective heartcutting will also be demonstrated using complex hydrocarbon streams.     

变压器油中溶解气体分析专用气相色谱仪的检定与校准

为解决检定变压器油中溶解气体分析专用气相色谱仪时遇到样品进样量计算不准,检测器对甲烷气体标准物质无响应,专用软件分析方法不能更改等问题,建立变压器油中溶解气体分析专用气相色谱仪的检定与校准方法。当进样模式为一次进样双柱分流时,按分流比计算分流到检测器的样品体积,其它进样模式按进样体积计算进样量;因色谱软件禁止积分导致CH_4在热导检测器上无响应时,应采用有证标准物质中的H_2或O_2进行检定与校准。以7890B型专用气相色谱仪为例,详细说明了变压器油中溶解气体分析专用气相色谱仪的检定与校准流程。该法为检定人员检定该类专用仪器时提供了参考。     

专用型国产气相仪及DNP填充柱测定白酒中的主要香味组分

 采用微机控制的国产气相仪和自制的DNP填充柱测定了白酒中的主要香味组分。通过对各种操作参数的优化 ,确立了等温及程序升温时合适的条件。该方法除可测定十余种主要醇、酯、醛组分外 ,还将分析对象扩大至丙酮、异戊醛、2 戊酮、2 戊醇、3 羟基 2 丁酮等组分 ,从而使采用这一技术可准确测定的组分增至 1 8种。在选定的条件下 ,仪器具有良好的稳定性 ,各香味组分定量结果的重复性好。并对科技部组织研制的这一专用气相仪的适用性作了研讨。     

Behavior of heavy solutes on a precolumn in on-column gas chromatography

The behavior of heavy solutes present in a sample injected on the precolumn has not been clarified in on-column injection onto gas chromatograph having a capillary column coupled to an uncoated precolumn in an oven. To investigate this point, an on-column gas chromatograph has been developed which is constructed with a heatable precolumn outside the oven. Some experiments were carried out in order to evaluate the performance. As a result, it was found that heavy solutes reach the first part of the main capillary column after the solvent has gone, resulting in sharp peaks without solvent effects. The reason why sharp peaks appear for the heavy solutes is also discussed. The cold-trapping effect has been shown to play an important role in narrowing the band width of the heavy solutes. Some of the advantages of the gas chromatograph developed are also presented.