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离子色谱仪维护及常见故障排除 总被引:1,自引:0,他引:1
简述了离子色谱仪的原理,详细介绍了离子色谱仪各个部件的日常维护。分析了在离子色谱仪日常使用中容易出现的故障,并提出了解决办法,有助于离子色谱仪器的有效工作并延长仪器使用寿命。 相似文献
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用定量体积排除色谱(SEC)法,从示差折光检测器的响应测定了多种水溶性高分子在纯水溶液中的折光指数增量,与常规静态方法所得结果相同,SEC用盐水溶液作为淋洗液时,盐水溶液类同于混合溶剂,溶质与周围溶剂的色谱分离过程与透析过程等同。在有柱和无柱的色谱装置条件下,从示差折光的检测响应值可分别导得恒定化学位和恒定溶剂组成下的折光指数增量νμ和νk。中性的聚丙烯酰胺在NaCl溶液中νμ>νk,表明NaC1分子被高分子链优先吸附。聚电解质聚苯乙烯磺酸钠的νμ<νk,表明水分子被优先吸附。 相似文献
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色谱分离最常见问题是峰形、分离状况、洗脱时间或性能的改变。可分两个步骤来处理不可接受的色谱分离。首先,从色谱方面来评价存在的问题,其次,对产生问题的原因进行独立分析。 相似文献
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用定量体积排除色谱法,从示差折光检测器的响应测定了多种水溶性高子分子在纯水溶液中的折光指数增量,与常规静态方法所得结果相同。SEC用盐水溶液作为淋洗液时,盐水溶液类同于混合溶剂,溶质与周围溶剂的色谱分离过程与透析过程等同。 相似文献
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对齐矣物中各单分散组分的折光指数增量、尺寸排除色谱响应面积与重量分数之间的相互关系作了数学分析。折光指数增量的分子量依赖性完全起源于端基效应,提出了一个对高分子的尺寸排除色谱谱图,作掀光指数增量改正的理论方程,其中包含端基与结构重复单元的分子量以及两者折光指数增量的比值,此比值可事先用Lorenz-Lorentz或Gladstone-Dale方程计算得到,理论的推断从苯乙烯齐聚物的HPSEC实验数据得到了证实。 相似文献
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介绍BT-99型水质分析仪在使用过程中经常出现的故障,分析了故障产生的可能原因,并提出了故障排除方法。 相似文献
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简要介绍了WPP2型平面光栅摄谱仪常见故障现象,对故障产生的原因进行了分析,归纳总结了故障排除的方法与过程. 相似文献
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张嘉璇 《分析测试技术与仪器》2018,24(4):256-258
对novAA400P石墨炉原子吸收光谱仪常见故障进行了分析总结,并结合应用实践给出了处理方法,可以快速准确地进行故障的处理,保证检测工作的顺利进行,同时对石墨炉原子吸收的日常维护进行了介绍. 相似文献
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N. R. Kuzelev A. S. Shtan’ G. I. Kiryanov L. N. Gall’ A. P. Knutarev G. S. Solov’ev A. V. Saprygin V. A. Kalashnikov D. V. Novikov A. B. Maleev V. A. Borodin V. G. Gorbunov Zh. A. Savina A. P. Ivanov 《Journal of Analytical Chemistry》2010,65(13):1382-1387
Product quality control within the nuclear fuel cycle is a subject of special concern in Russia nowadays. Earlier, mass spectrometers of foreign production were commonly used for elemental and isotope analysis of samples. Currently, a series of domestic mass spectrometers MTI-350 has been developed and their production has been organized in Russia. The series comprises an automated MTI-350G mass spectrometer for the isotope analysis of uranium hexafluoride; thermal ionization MTI-350T mass spectrometer for the isotope analysis of uranium, plutonium, and mixed oxide (MOX) fuels; an MTI-350GS mass spectrometer for controlling the production of uranium hexafluoride; and an MTI-350GP mass spectrometer for the determination of the impurity concentration in uranium hexafluoride. The article considers operation principles, analytical characteristics, and the advantages of the above mass spectrometers. 相似文献
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Hisao Shimizu Fumihiro Jinno Akio Morohashi Yuzo Yamazaki Masaki Yamada Takahiro Kondo Satoru Asahi 《Journal of mass spectrometry : JMS》2012,47(8):1015-1022
We investigated the application of a high‐resolution Orbitrap mass spectrometer equipped with an electrospray ionization (ESI) source and a matrix‐assisted laser desorption/ionization‐time‐of‐flight (MALDI‐TOF) mass spectrometer to the metabolite profiling of a model small interfering RNA (siRNA) duplex TSR#34 and compared their functions and capabilities. TSR#34 duplex was incubated in human serum in vitro, and the duplex and its metabolites were then purified by ion exchange chromatography in order to remove the biological matrices. The fraction containing the siRNA duplex and its metabolites was collected and desalted and then subjected to high‐performance liquid chromatography (HPLC) equipped with a reversed phase column. The siRNA and its metabolites were separated into single strands by elevated chromatographic temperature and analyzed using the ESI‐Orbitrap or the MALDI‐TOF mass spectrometer. Using this method, the 5' and/or 3' truncated metabolites of each strand were detected in the human serum samples. The ESI‐Orbitrap mass spectrometer enabled differentiation between two possible RNA‐based sequences, a monoisotopic molecular mass difference which was less than 2 Da, with an intrinsic mass resolving power. In‐source decay (ISD) analysis using a MALDI‐TOF mass spectrometer allowed the sequencing of the RNA metabolite with characteristic fragment ions, using 2,4‐dihydroxyacetophenone (2,4‐DHAP) as a matrix. The ESI‐Orbitrap mass spectrometer provided the highest mass accuracy and the benefit of on‐line coupling with HPLC for metabolite profiling. Meanwhile, the MALDI‐TOF mass spectrometer, in combination with 2,4‐DHAP, has the potential for the sequencing of RNA by ISD analysis. The combined use of these methods will be beneficial to characterize the metabolites of therapeutic siRNA compounds. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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A. S. Samokhin A. I. Revel’skii I. A. Revel’skii 《Journal of Analytical Chemistry》2011,66(14):1432-1436
Low-resolution electron ionization mass spectra recorded on various types of mass spectrometers (time-of-flight, quadrupole,
and three-dimensional ion trap) were compared. A model mixture of 10 organic compounds (MW < 200 Da) was analyzed by gas chromatography-mass
spectrometry. Pure mass spectra of analytes were extracted using the AMDIS software. The best repeatability was achieved for
the time-of-flight mass spectrometer. The mass spectra recorded by a quadrupole and a time-of-flight mass spectrometer were
quite similar. In the case of these instruments, library search using a commercial mass spectral data base (NIST’05) gave
satisfactory result for each analyte (rank 1 or 2 in the “hit list”; Match > 900). In some cases, the mass spectra of model
compounds recorded by the ion trap mass spectrometer differed in intensity of certain mass spectral peaks (but not in the
set of peaks) from the mass spectra presented in the library and from the experimental mass spectra recorded by the time-of-flight
and quadrupole instruments. 相似文献
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Jackson SN Mishra S Murray KK 《Rapid communications in mass spectrometry : RCM》2004,18(18):2041-2045
Matrix-assisted laser desorption/ionization (MALDI) was used for the on-line analysis of single particles. An aerosol was generated at atmospheric pressure and particles were introduced into a time-of-flight (TOF) mass spectrometer through a single-stage differentially pumped capillary inlet. Prior to entering the mass spectrometer, a matrix was added to the particles using a heated saturator and condenser. A liquid matrix, 3-nitrobenzyl alcohol (NBA), and a solid matrix, picolinic acid (PA), were used. Particles were ablated with a 351 nm excimer laser and the resulting ions were mass-separated in a two-stage reflectron TOF mass spectrometer. Aerosol particles containing the biomolecules erythromycin and gramicidin S were analyzed with and without the matrix addition step. The addition of NBA to the particles resulted in mass spectra that contained an intact molecular ion mass peak. In contrast, PA-coated particles did not yield molecular ion peaks from matrix-coated particles. 相似文献
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Summary An ion-trap mass spectrometer for determination of quaternary ammonium herbicides in water samples is evaluated. Implementation
of the method previously optimized in a quadrupole mass spectrometer (VG Platform II) in an ion-trap (LCQ) required modifications
to the sample inlet of the electrospray source. Quality parameters were established and detection limits, after trace enrichment,
range 5–50 ng L−1. Good reproducibilities (day-to-day and run-to-run) <12% were obtained. The method was applied to analysis of spiked samples
and the results were comparable with those determined using a quadrupole mass spectrometer. 相似文献
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A 252Cf plasma desorption mass spectrometer has been set up to analyse thin layers of non-volatile organic samples. Molecular and fragment ions were produced and their mass was determined by a time-of-flight measurement. A novel interface combines a high-performance liquid chromatograph with the 252Cf plasma desorption mass spectrometer in a twofold way: introducing the effluent continuously through a capillary inlet in the on-line liquid chromatography mass spectrometry mode or transferring already prepared samples through a vacuum lock into the mass spectrometer in the off-line liquid chromatography+mass spectrometry mode. The off-line mode has been applied for the quantitative analysis of pharmaceuticals in blood using stable isotope labelled standards. 相似文献