共查询到20条相似文献,搜索用时 140 毫秒
1.
《天然气化学杂志》2006,15(4):I0007-I0008
A G Abdullah,Zalizawati,247 Ah6n,Vfotor R.,307 Alavi,S.M.,327 Amin,Nor Aishah Saidina 191,259,340 Ammasi,Sriraj,191 An,G的jun,127 Anggoro,Didi Dwi,340 Ge,Zhonghua,164 Gu,Y.,73 Guo,Bo,223 Guo,Jianjun,52 Guo,Xiaohui,105 H B Bai,Liang,105 Bakar,W.Azelee W.Abu,259 Bao,Xinhe,181 Batuev,Lubsan,149 Burgina,Elena,149 Ha£axlioglu,P.,73 Han,Huajun,303 Hong,Kong Bee,266 Hu,Xiaofang,58 Hu,Xi加jun,100 Huang,Shengjun,93 Huang,Xingyun,3… 相似文献
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用ICP研究鹿科动物骨质疏松症的微量元素特征 总被引:1,自引:0,他引:1
鹿科动物的骨质疏松症是近几年出现的一种疾病,它影响鹿的生长发育和繁殖,病重者死亡。我们采集梅花鹿和白唇鹿的毛,血样,用低温灰化方法和温法消解处理样品,用ICP分析了毛,血清中微量元素的含量。病梅花鹿毛样中Mg,Al,Ca,Ti,Fe,Cu,Zn的含量比正常组高,Ti,Cu,Zn的偏差率大于15%,而Si,Mn,P,P,Ag,Ba,La,Ce,Pb比正常组低,V,Ag,Ba,La,Ce,Pb存在... 相似文献
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对梅州农村饮用水中的重金属元素进行了监测和分析,选择Fe,Mn,Zn,Cu,Ag,Pb,Cd七种元素为检测指标。从实验结果来看,Cu,Ag,Cd含量低,未超标;Fe,Mn,Zn,Pb有超标现象:按其危害程度,Pb,Mn的超标是急需解决的问题。 相似文献
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用ICP-AES方法,对30例大肠癌,26例溃疡性结肠炎进行血清钼,锌,铬铁,铜,锰,铅,铝,硒,铋,钡,钛,钴,钒等微量元素测定,并与20例健康者对照。结果显示大肠癌组血清钼,锌,铬,低于对照组钼,锌,铬,P分别〈0.01,〈0.05,〈0.05;溃疡性结肠炎组钼低于对照组,P〈0.05。提示微量元素代谢异常可能直接影响酶系统,使自由基失控,体内促氧化和抗氧化平衡失调,促使肿瘤的发生。 相似文献
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何小英 《广东微量元素科学》1997,4(11):70-73
脑梗塞是常见病,且大部分可引起偏瘫,失语,智能障碍等后遗症,严重影响病人的生存质量,广州市第六人民医院于1995年1月~1997年6月采用中西药物,传统治疗,功能障碍治疗,心理治疗,氦氖激光血管内照射,血液光量子疗法,高压氧等综合治疗脑梗塞68例,总疗程3个月,结果,总有效率94.1%,显效率64.1%,明显高于单用药物治疗的显效率,说明综合治疗可提高疗效,减少后遗症及致残率,且病程越短,疗效越好 相似文献
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1,2,4-三嗪类化合物的研究(ⅩⅫ)──咪唑并-(5,4-e)-1,2,4-三嗪衍生物的合成沙耀武,蔡孟深(北京医科大学药学院,北京,100083)关键词乙二脒腙,原甲酸三乙酯,1,2,4-三嗪,咪唑并-(5,4-e)-1,2,4-三嗪天然碱基拮抗... 相似文献
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聚合物与有机染料多层复合膜电致发光颜色的直流电压调制马於光,薛善华,黄劲松,田文晶,刘式墉,沈家骢,刘晓冬(吉林大学分子光谱与分子结构开放实验室,集成光电子学国家重点实验室,长春,130023)(白求恩医科大学,长春,130023)关键词聚合物,发光... 相似文献
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Ion mobility-mass spectrometry 总被引:3,自引:0,他引:3
This review article compares and contrasts various types of ion mobility-mass spectrometers available today and describes their advantages for application to a wide range of analytes. Ion mobility spectrometry (IMS), when coupled with mass spectrometry, offers value-added data not possible from mass spectra alone. Separation of isomers, isobars, and conformers; reduction of chemical noise; and measurement of ion size are possible with the addition of ion mobility cells to mass spectrometers. In addition, structurally similar ions and ions of the same charge state can be separated into families of ions which appear along a unique mass-mobility correlation line. This review describes the four methods of ion mobility separation currently used with mass spectrometry. They are (1) drift-time ion mobility spectrometry (DTIMS), (2) aspiration ion mobility spectrometry (AIMS), (3) differential-mobility spectrometry (DMS) which is also called field-asymmetric waveform ion mobility spectrometry (FAIMS) and (4) traveling-wave ion mobility spectrometry (TWIMS). DTIMS provides the highest IMS resolving power and is the only IMS method which can directly measure collision cross-sections. AIMS is a low resolution mobility separation method but can monitor ions in a continuous manner. DMS and FAIMS offer continuous-ion monitoring capability as well as orthogonal ion mobility separation in which high-separation selectivity can be achieved. TWIMS is a novel method of IMS with a low resolving power but has good sensitivity and is well intergrated into a commercial mass spectrometer. One hundred and sixty references on ion mobility-mass spectrometry (IMMS) are provided. 相似文献
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Maxwell SL Culligan BK Jones VD Nichols ST Bernard MA Noyes GW 《Analytica chimica acta》2010,682(1-2):130-136
A new method for the determination of (237)Np and Pu isotopes in large soil samples has been developed that provides enhanced uranium removal to facilitate assay by inductively coupled plasma mass spectrometry (ICP-MS). This method allows rapid preconcentration and separation of plutonium and neptunium in large soil samples for the measurement of (237)Np and Pu isotopes by ICP-MS. (238)U can interfere with (239)Pu measurement by ICP-MS as (238)UH(+) mass overlap and (237)Np via (238)U peak tailing. The method provides enhanced removal of uranium by separating Pu and Np initially on TEVA Resin, then transferring Pu to DGA resin for additional purification. The decontamination factor for removal of uranium from plutonium for this method is greater than 1×10(6). Alpha spectrometry can also be applied so that the shorter-lived (238)Pu isotope can be measured successfully. (239) Pu, (242)Pu and (237)Np were measured by ICP-MS, while (236)Pu and (238)Pu were measured by alpha spectrometry. 相似文献
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采用萃取纳升喷雾结合离子迁移谱技术,建立了化妆品中8种禁用抗生素的现场快速筛查方法。对萃取纳升喷雾毛细管拉制条件、萃取纳升喷雾离子化条件、离子迁移谱检测条件等进行了详细考察和优化。在优化的实验条件下,8种禁用抗生素的方法检出限为20 mg/kg,离子迁移谱分析时间小于20 ms,单个样品全部检测时间不超过30 s。对于筛检出的疑似阳性样品,进一步采用超高效液相色谱-串联质谱进行确证。该方法流程简便、快捷高效,为化妆品中违禁组分的现场快速筛查提供了较为广阔的应用前景。 相似文献
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Zhang X Jin QK Carr SA Annan RS 《Rapid communications in mass spectrometry : RCM》2002,16(24):2325-2332
Determining the phosphorylation stoichiometry at specific sites in a phosphoprotein is a very challenging task. We describe here a novel mass spectrometry based method that is capable of measuring the absolute phosphorylation stoichiometry at specific sites without the need for specific internal standards, phospho-site antibodies or radioactivity. The method is based on a gentle chemical labeling strategy which specifically and differentially labels the N-terminus of all peptides in a sample with either a D(5)- or D(0)-propionyl group and measures the ratio of the abundance of the D(5)/D(0) peptide pairs simultaneously using mass spectrometry. Using matrix-assisted laser desorption/ionization (MALDI), the method can measure absolute stoichiometry to within at least 10% and can be applied to both in vitro and in vivo phosphorylated peptides and proteins. Furthermore, this method can potentially be applied to the quantitative study of other types of protein post-translational modifications, and the profiling of protein expression on the proteome level. 相似文献
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Magen E. Coleman Evelyn M. Bond W. Allen Moody Lav Tandon 《Journal of Radioanalytical and Nuclear Chemistry》2013,296(1):483-487
Uranium-232 is an isotope of interest for nuclear forensic studies because it can provide information on the irradiation history of a sample of uranium. The isotope is formed in uranium materials through several pathways and is typically found at ultra-trace levels (usually ng/g or smaller) in typical uranium materials. The low abundance of this isotope in irradiated materials makes it very difficult to measure accurately and precisely. Many different methods have been proposed for the analysis of 232U using radiochemical methods including alpha and gamma spectrometry. In this paper, literature methods will be discussed and an improved method using alpha spectrometry will be presented. Alpha spectrometry offers a direct analysis technique for measuring 232U, with few interferences that can be removed via separations. Results from our improved method will be presented and compared to results obtained from a non-destructive gamma spectrometry method that utilizes an indirect measurement. LA-UR-12-20186. 相似文献
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Ha NY Kim SH Lee TG Han SY 《Langmuir : the ACS journal of surfaces and colloids》2011,27(16):10098-10105
We demonstrate that the microwave-assisted protein enzymatic digestion (MAPED) method can be successfully applied to the mass spectrometric characterization of proteins captured on the affinity surfaces of protein chips. The microwave-assisted on-chip tryptic digestion method was developed using a domestic microwave, completing the on-chip proteolysis reaction in minutes, whereas the previous on-chip digestion methods by incubation took hours of incubation time. For the model protein chips, antibody-presenting surfaces were prepared, where anti-α-tubulin1 and antibovine serum albumin (BSA) were immobilized on self-assembled monolayers. The resulting digestion efficiency, displaying sequence coverages of 30 and 14% for α-tubulin1 and BSA, respectively, was comparable to the previous time-consuming incubation studies. It allowed the characterization of immunosensed proteins by MASCOT search using peptide mass fingerprinting. In an example of this method for protein chip applications, BSA naturally involved in fetal bovine serum was unambiguously identified on a model protein chip by imaging mass spectrometry. This work shows that biomass spectrometry techniques can be implemented for surface mass spectrometry and biochip applications. Along with recent advances in imaging mass spectrometry, this technique will provide a new opportunity for high-speed, and thus high-throughput in the future, label-free mass spectrometric assays using protein arrays. 相似文献
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Quienly Godoi Dario Santos Jr. Lidiane C. Nunes Flávio O. Leme Iolanda A. Rufini José A.M. Agnelli Lilian C. Trevizan Francisco J. Krug 《Spectrochimica Acta Part B: Atomic Spectroscopy》2009
The performance of laser-induced breakdown spectrometry (LIBS) for the determination of Ba, Cd, Cr and Pb in toys has been evaluated by using a Nd:YAG laser operating at 1064 nm and an Echelle spectrometer with intensified charge-coupled device detector. Samples were purchased in different cities of São Paulo State market and analyzed directly without sample preparation. Laser-induced breakdown spectrometry experimental conditions (number of pulses, delay time, integration time gate and pulse energy) were optimized by using a Doehlert design. Laser-induced breakdown spectrometry signals correlated reasonably well with inductively coupled plasma optical emission spectrometry (ICP OES) concentrations after microwave-assisted acid digestion of selected samples. Thermal analysis was used for polymer identification and scanning electron microscopy to visualize differences in crater geometry of different polymers employed for toy fabrication. Results indicate that laser-induced breakdown spectrometry can be proposed as a rapid screening method for investigation of potentially toxic elements in toys. The unique application of laser-induced breakdown spectrometry for identification of contaminants in successive layers of ink and polymer is also demonstrated. 相似文献
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Xiu‐Fang Yan Yan‐Mei Liang Bo Zhou Jun Bin Chao Kang 《Journal of separation science》2020,43(13):2718-2727
The high selectivities of liquid chromatography and mass spectrometry make liquid chromatography–mass spectrometry one of the most popular tools for quantitative analysis in complex chemical, biological, and environmental systems, while the potential mathematical selectivity of liquid chromatography–mass spectrometry is rarely investigated. This work discussed the mathematical selectivity of liquid chromatography–mass spectrometry by three‐way calibration based on the trilinear model, with an application to quantitative analysis of coeluting aromatic amino acids in human plasma. By the trilinear decomposition of the constructed liquid chromatography–mass spectrometry‐sample trilinear model and individual regression of the decomposed relative intensity versus concentration, the proposed three‐way calibration method successfully achieved quantitative analysis of coeluting aromatic amino acids in human plasma, even in the presence of uncalibrated interferent(s) and a varying background. This analytical method can ease the requirements for sample preparation and complete chromatographic separation of components, reduce the use of organic solvents, decrease the time of chromatographic separation, and increase the peak capacity of liquid chromatography–mass spectrometry. As a “green analytical method”, the liquid chromatography–mass spectrometry three‐way calibration method can provide a promising tool for direct and fast quantitative analysis in complex systems containing uncalibrated spectral interferents, especially for the situation where the coelution problem is difficult to overcome. 相似文献
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基于静电场轨道阱高分辨质谱技术,建立化妆品中20种香料成分的高通量检测方法,并应用于实际样品中香料成分的筛查与定量分析。利用香料成分标准品通过高分辨质谱正负离子切换FullMS/ddM S^2扫描方式分析,获得多种香料成分的保留时间、一级母离子和二级碎片离子精确质量数,构建香料成分筛查谱库。样品用甲醇超声提取后,经超高效色谱柱分离,采用高分辨质谱分析,利用TraceFinder软件对化妆品中的香料成分与谱库相关信息匹配,实现目标物的高通量筛查确证,筛查确认后利用一级母离子外标法进行香料成分的定量分析。经验证该方法的线性关系良好(R^2>0.99),方法的检出限(0.1~10μg/g)、回收率(89.6%~109.1%)和精密度(3.1%~9.2%)能够满足欧盟对香料成分标注的限量要求,可用于同时测定化妆品中多种香料成分。 相似文献