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基于微热板表面离子化源的离子迁移率谱仪研究 总被引:1,自引:0,他引:1
根据表面离化机理和离子迁移率谱检测方式,设计和制备了一种基于表面离化源的离子迁移率谱仪(IMS)。表面离化源为采用微机电系统(MEMS)工艺加工的微热板阵列,除了作为离子产生器,还作为漂移管的一个离子栅,用以实现离子向漂移区的注入。测试了该IMS对三乙胺的响应特性并研究了离子注入时间对离子迁移率谱的影响。结果表明,基于微热板表面离化源的离子迁移率谱仪对三乙胺具有很好的动态响应特性,三乙胺浓度的平方根与离子峰面积具有较好的线性关系,检出限可达6×10-8(V/V)。此外,与传统的放射离化IMS相比,这种IMS还具有离子注入时间短和离子迁移率谱基电流为零等特点。 相似文献
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以氩离子团簇为溅射源,对采用一步旋涂法制备的CH3NH3PbI3钙钛矿薄膜进行溅射实验,通过XPS分析检测样品表面Pb元素的价态变化。结果表明,新制备的钙钛矿薄膜材料表面没有检测出Pb0,而经过团簇离子枪溅射的样品中部分Pb2+还原成Pb0,证明了氩离子团簇刻蚀对钙钛矿材料具有破坏作用。一方面,溅射时间的增加以及团簇离子枪能量的增大均会加大钙钛矿材料的损伤程度;另一方面,离子枪团簇规模大小与溅射损伤程度呈近抛物线关系。因此,在进行此类样品表面清洁时,应尽量减小离子枪能量和溅射时间,选择较小或较大的团簇规模以减少对样品的损伤。该研究对于钙钛矿样品在进行XPS检测和数据分析时具有参考价值。 相似文献
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采用新型离子表面印迹材料在皮米尺度上对相邻稀土离子进行识别分离的研究 总被引:2,自引:0,他引:2
将丙烯腈接枝聚合于硅胶微粒表面, 然后将接枝的聚丙烯腈转化为聚偕胺肟(PAO), 制得了功能接枝微粒PAO/SiO2. 采用本课题组建立的新型分子表面印迹技术, 以稀土钆离子为模板离子, 戊二醛为交联剂, 对接枝在硅胶表面的PAO大分子链进行了离子印迹(IIP), 制备了钆离子表面印迹材料IIP-PAO/SiO2. 以与钆元素相邻的稀土元素铕及钐的离子为对比物, 采用静态与动态两种方法, 考察研究了表面印迹材料IIP-PAO/SiO2对钆离子的结合性能与离子识别特性. 研究结果表明, 离子表面印迹材料IIP-PAO/SiO2对钆离子具有特异的识别选择性与优良的结合亲和性. 相对于离子半径与其仅差1~3 pm的相邻稀土离子铕离子及钐离子, IIP-PAO/SiO2对钆离子的识别选择性系数分别为7.49与7.93. 此外, 印迹材料IIP-PAO/SiO2还具有良好的洗脱性能, 以稀盐酸溶液作为洗脱液, 29个床体积内解吸率可达99.54%. 相似文献
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本实验室研制了国内首台宽离子能量检测范围飞行时间质谱仪。仪器采用紧凑式电子轰击源设计,配合离子透镜系统有效的调制离子流,飞行时间质量分析器采用了离子垂直引入式,双场加速和双场反射以及大尺寸MCP检测装置设计。仪器单离子信号半峰宽约2 ns,仪器分辨率优于1600FWHM,检测实际样品质量范围为1~127 amu(仪器理论质量检测上限优于800 amu),可检测离子能量范围优于2个数量级(3~140 eV)。若该TOF质量分析器与短瞬高压脉冲放电离子源耦合联用,可广泛应用于高能离子束的快速检测,如真空阴极放电对制备薄膜、离子注入材料的表征,导电材料的离子电荷态分布以及离子扩散速度的测定等。 相似文献
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《化学研究与应用》2021,33(9)
采用离子印迹技术,以铅离子为模板,苯硫酚用于识别位点的形成,使铅离子与苯硫酚通过自组装的办法形成非共价键的相互作用,正十四烷基硫醇用于封闭未彻底组装的金电极的表面,制备了铅离子印迹电化学传感器。采用差分脉冲阳极溶出伏安法(DPASV)考察了支持电解质的种类、浓度、酸度、富集时间和脉冲周期对测定的影响。在优化的实验条件下,铅离子浓度在1.0×10~(-10 )~1.0×10~(-5 )mol·L~(-1 )范围内与溶出电流呈良好的线性关系,相关系数为0.9973,检出限为1.0×10~(-11 )mol·L~(-1)。该方法具有良好的重现性和稳定性,有望用于实际样品的检测。 相似文献
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A novel surface ionization source for ion mobility spectrometer 总被引:1,自引:0,他引:1
A surface ionization (SI) source is designed and prepared for ion mobility spectrometer (IMS). The source acts not only as an emitter but also an ion injector which can inject ions periodically into the drift region of drift tube. Using the dual-role source, the dimension of the drift tube can be decreased and the circuit for high voltage can be simplified efficiently. The IMS with the SI source has a response range of ∼4 orders of magnitude and a good reproducibility to tri-ethylamine. Compared with radioactive ionization (RI), the ultra-short time for ion injection and the zero level base line of ion mobility spectrum are characteristics of the surface ionization. 相似文献
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离子迁移谱仪的性能受到多种因素的影响,如漂移管电场强度离子门脉冲宽度、离子源工作条件、漂移管尺寸、离子门加工工艺和屏蔽网透过率等。在实际应用中需要对漂移管电场强度和离子门脉冲宽度进行调整以平衡灵敏度和分辨率。本研究详细研究了漂移管电场强度和离子门脉冲宽度对微波诱导等离子体离子迁移谱( MIPI-IMS)分辨率和灵敏度的影响。实验结果表明,存在一个最佳电场强度值使得分辨率达到最大,而且不同离子门脉冲宽度对应的最佳电场强度值不同;增大电场强度和离子门脉冲宽度有利于灵敏度的提升。与其它离子流较弱的离子源相比,离子流较大的微波诱导等离子体离子源在实际应用中对离子门脉冲宽度和漂移管电场强度有更多的选择。此研究结果有助于MIPI-IMS仪器性能的提升。将异丙醇用于测试MIPI-IMS的性能,结果表明,MIPI-IMS在保持较低检出限(7.7×10-11, V/V)的同时,分辨率可以达到66。 相似文献
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Liang X Han H Xia Y McLuckey SA 《Journal of the American Society for Mass Spectrometry》2007,18(3):369-376
A pulsed triple ionization source, using a common atmosphere/vacuum interface and ion path, has been developed to generate different types of ions for sequential ion/ion reaction experiments in a linear ion trap-based tandem mass spectrometer. The triple ionization source typically consists of a nano-electrospray emitter for analyte formation and two other emitters, an electrospray emitter and an atmospheric pressure chemical ionization emitter or a second nano-electrospray emitter for formation of the two different reagent ions. The three emitters are positioned in a parallel fashion close to the sampling orifice of the tandem mass spectrometer. The potentials applied to each emitter are sequentially pulsed so that desired ions are generated separately in time and space. Sequential ion/ion reactions take place after analyte ions of interest and different set of reagent ions are sequentially injected into a linear ion trap, where axial trapping is effected by applying an auxiliary radio frequency voltage to the end lenses. The pulsed triple ionization source allows independent optimization of each emitter and can be readily coupled to any atmospheric pressure ionization interface with no need for instrument modifications, provided the potentials required to transmit the ion polarity of interest can be synchronized with the emitter potentials. Several sequential ion/ion reactions examples are demonstrated to illustrate the analytical usefulness of the triple ionization source in the study of gas-phase ion/ion chemistry. 相似文献
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F. W. Rllgen P. Dhling E. Bramer-Weger F. Okuyama M. Subhan 《Journal of mass spectrometry : JMS》1986,21(10):623-627
The negative ion mode of field desorption mass spectrometry is matrix dependent. The matrix is used to facilitate the desolvation of ions at field strengths below the onset of field induced electron detachment. The role of the matrix in the desolvation mechanism for negative ions is briefly described and the main properties of a matrix solution, such as viscosity, solubility for complex salts and acids, and adhesion to the emitter surface, on the ion formation are discussed. The application of matrix mixtures with strong adhesion to the emitter surface even at elevated temperatures and high field strengths are considered to be important for the further improvement of this ionization method. 相似文献
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Emese Peintler‐Krivan Gary J. Van Berkel Vilmos Kertesz 《Rapid communications in mass spectrometry : RCM》2010,24(9):1327-1334
An emitter electrode with an electroactive poly(pyrrole) (PPy) polymer film coating was constructed for use in electrospray ionization mass spectrometry (ESI‐MS). The PPy film acted as a surface‐attached redox buffer limiting the interfacial potential of the emitter electrode. While extensive oxidation of selected analytes (reserpine and amodiaquine) was observed in positive ion mode ESI using a bare metal (gold) emitter electrode, the oxidation was suppressed for these same analytes when using the PPy‐coated electrode. A semi‐quantitative relationship between the rate of oxidation observed and the interfacial potential of the emitter electrode was shown. The redox buffer capacity, and therefore the lifetime of the redox buffering effect, correlated with the oxidation potential of the analyte and with the magnitude of the film charge capacity. Online reduction of the PPy polymer layer using negative ion mode ESI between analyte injections was shown to successfully restore the redox buffering capacity of the polymer film to its initial state. Published in 2010 by John Wiley & Sons, Ltd. 相似文献
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Lee Chuin Chen Md. Matiur Rahman Kenzo Hiraoka 《Journal of mass spectrometry : JMS》2012,47(8):1083-1089
Standard field desorption (FD) ionization is implemented under high vacuum condition. In this paper, non‐vacuum FD is performed under a super‐atmospheric pressure environment using untreated tungsten wires as FD emitter, and the ion source was coupled to a commercial linear ion trap mass spectrometer. The operating pressure of the ion source was 6 bars which was high enough to provide sufficient dielectric strength to the working gas so that the high voltage that was required for FD could be applied to the emitter without occurrence of electrical discharge. Non‐volatile sample deposited on the bare tungsten wire FD emitter was heated by flowing direct current through the emitter. Similar to vacuum FD, the formation of conical protrusion of the liquefied sample layer under the strong electric field was also observed. Using the present ion source, high pressure field‐desorption of polar neutral compounds, organic salts and ionic liquids is demonstrated. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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A combined surface sampling probe/electrospray emitter coupled with an ion trap mass spectrometer was used for the direct read out of unmodified reversed-phase C18 thin-layer chromatography (TLC) plates. The operation of the surface sampling electrospray ionization interface in positive and negative ionization modes was demonstrated through the direct analysis of TLC plates on which a commercial test mix comprised of four dye compounds viz., rhodamine B, fluorescein, naphthol blue black, and fast green FCF, and an extract of the caffeine-containing plant Ilex vomitoria, were spotted and developed. Acquisition of full-scan mass spectra and automated collection of MS/MS product ion spectra while scanning a development lane along the surface of a TLC plate demonstrated the advantages of using an ion trap in this combination. Details of the sampling system, benefits of analyzing a developed lane in both positive ion and negative ion modes, levels of detection while surface scanning, surface scan speed effects, and the utility of three-dimensional data display, are also discussed. 相似文献
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《Analytical letters》2012,45(8):1498-1520
Amalgamation of mass spectrometry (MS) and proteomics has led to the most awaited technological inventions such as discovery of clinically potential biomarkers and generation of effective drugs. This review focuses on the synergistic growth in MS instrumentation, proteomics and its impact on biomedical sciences. Novel ionization methods: surface enhanced laser desorption ionization, electrospray assisted laser desorption ionization, desorption electrospray ionization, laser diode thermal desorption are discussed. Different mass analyzers: ion trap, time-of-flight, Fourier transform ion cyclotron resonance and their applications are outlined. New ion fragmentation techniques: electron capture dissociation, electron transfer dissociation, infrared multiphoton dissociation and their attributes are described. 相似文献
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Jonathan T. Cox Ioan Marginean Ryan T. Kelly Richard D. Smith Keqi Tang 《Journal of the American Society for Mass Spectrometry》2014,25(12):2028-2037
Arrays of chemically etched emitters with individualized sheath gas capillaries were developed to enhance electrospray ionization (ESI) efficiency at subambient pressures. By incorporating the new emitter array in a subambient pressure ionization with nanoelectrospray (SPIN) source, both ionization efficiency and ion transmission efficiency were significantly increased, providing enhanced sensitivity in mass spectrometric analyses. The SPIN source eliminates the major ion losses of conventional ESI-mass spectrometry (MS) interfaces by placing the emitter in the first reduced pressure region of the instrument. The new ESI emitter array design developed in this study allows individualized sheath gas around each emitter in the array making it possible to generate an array of uniform and stable electrosprays in the subambient pressure (10 to 30 Torr) environment for the first time. The utility of the new emitter arrays was demonstrated by coupling the emitter array/SPIN source with a time of flight (TOF) mass spectrometer. The instrument sensitivity was compared under different ESI source and interface configurations including a standard atmospheric pressure single ESI emitter/heated capillary, single emitter/SPIN and multi-emitter/SPIN configurations using an equimolar solution of nine peptides. The highest instrument sensitivity was observed using the multi-emitter/SPIN configuration in which the sensitivity increased with the number of emitters in the array. Over an order of magnitude MS sensitivity improvement was achieved using multi-emitter/SPIN compared with using the standard atmospheric pressure single ESI emitter/heated capillary interface. Graphical Abstract
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A. A. Makarov A. A. Grechnikov S. M. Nikiforov O. A. Tyutyunnik E. V. Denisov 《Journal of Analytical Chemistry》2013,68(14):1165-1169
The results of a study on interfacing an Orbitrap mass analyzer with direct ion injection to a surface assisted laser desorption/ionization (SALDI) ion source are presented. Osmium complexes with 8-mercaptoquinoline were studied. Titanium oxide thin films prepared by electron beam evaporation were found an effective emitter of the ions of the test complexes. It was demonstrated that interfacing the Orbitrap mass analyzer to a SALDI source can significantly improve the analytical performance of this method in comparison to a typical combination of SALDI/time-of-flight mass spectrometer. 相似文献