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Ion Transmission in the first vacuum stage of an Inductively Coupled Plasma Mass SpectrometerMacedone, Jeffrey Harris 28 March 2005 (has links) (PDF)
The inductively coupled plasma mass spectrometer (ICP-MS) is the instrument of choice for trace and ultra-trace elemental analysis. However, the ICP-MS suffers from matrix effects. Matrix effects occur when instrument response varies as the composition of the sample matrix is changed. Matrix effects, or non-spectroscopic interferences, limit the accuracy of routine analysis. Identification of the sources of matrix effects provide a basis for reducing or eliminating them. As inaccuracies in the ICP-MS are more severe than those in the ICP atomic emission spectrometer, the problem may be due, at least in part, to the vacuum interface used to couple the plasma source and mass spectrometer. The research herein is a study of matrix effect sources in the first stage of the vacuum interface. This study utilized laser-induced fluorescence of atomic species to identify factors affecting analyte transport through the sampling orifice of the vacuum interface. Several non-idealities in the performance of the interface were found. (1) Operating conditions and sample compositions can negatively affect the efficiency with which ions are extracted through the vacuum interface coupling the plasma source to the mass spectrometer. (2) The sampling cone itself was found to suppress and narrow ion distributions in the plasma. (3) Changes in the degree of ionization were identified in the first vacuum stage. The evidence of recombination and state-changing collisions was observed in the first vacuum stage at lower power settings. Matrix effects occur in the first vacuum stage, the first step of the ion extraction process. This work shows that changes in ion transport through the first vacuum stage of the vacuum interface of an ICP-MS affect the overall performance of the instrument.
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Comparing Theory and Experiment for Analyte Transport in the First Vacuum Stage of the Inductively Coupled Plasma Mass SpectrometerZachreson, Matthew R. 08 December 2012 (has links) (PDF)
The Direct Simulation Monte Carlo algorithm as coded in FENIX is used to model the transport of trace ions in the first vacuum stage of the inductively coupled plasma mass spectrometer. Haibin Ma of the Farnsworth group at Brigham Young University measured two radial trace density profiles: one 0.7 mm upstream of the sampling cone and the other 10 mm downstream. We compare simulation results from FENIX with the experimental results. We find that gas dynamic convection and diffusion are unable to account for the experimentally-measured profile changes from upstream to downstream. Including discharge quenching and ambipolar electric fields, however, makes it possible to account for the way the profiles change.
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Trace element analysis of human tooth enamel by laser ablation-inductively coupled plasma-mass spectrometry for estimation of region of originJones, Meaghan Elisabeth 22 January 2016 (has links)
Tooth enamel is among the most durable substances in the human body and as such has high recoverability in forensic anthropology cases. Its crystalline hydroxyapatite matrix has a slightly variable chemical composition which incorporates biologically available trace elements. The trace elements are derived from an individual's diet and the water he or she consumes during the period of enamel formation. As a result, trace element profiles of enamel can reflect the geology, pollution, and certain cultural dietary factors of the area in which the individual resided during this period.
This research examines a sample of teeth with known demographic information from the Antioquia Modern Skeletal Reference Collection in Medellin, Colombia. A sample set of 75 teeth from 61 individuals born in areas throughout northwestern Colombia were analyzed using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), a minimally destructive, semi-quantitative technique. Analysis was performed at the Center for Archaeology, Materials, and Applied Spectroscopy (CAMAS) at Idaho State University.
33 elements were analyzed in the sample. Nonparametric methods were used to assess the relationship between elemental profiles and region of origin. Sr, Mo, Ag, Ba, Eu, and Tm concentration profiles were found to vary among regional groups. Al, Ni, Cr, Mn, Co, Sr, Cd, Sb, Sm, Eu, and U were found to predict region of origin. Differences in municipality were classified with 72% accuracy, variation across the department of Antioquia was classified with 67% accuracy, and the age of the geologic substrate was classified with 67% accuracy. The results suggest that trace element analysis of permanent tooth enamel may be of some use in estimating an individual's region of origin in forensic anthropological contexts. Further research with both larger sample sizes and more geographic variation is necessary.
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The Neolithic and late Iron Age Pottery from Pool, Sanday, Orkney: An archaeological and technological consideration of coarse pottery manufacture at the Neolithic and late Iron Age site of Pool, Orkney incorporating X-Ray Fluorescence, Inductively Coupled Plasma Spectrometric and Petrological Analyses.MacSween, Ann January 1990 (has links)
The Neolithic and late Iron Age pottery from the
settlement site of Pool, Sanday, Orkney, was studied
on two levels. Firstly, a morphological and technological
study was carried out to establish a sequence
for the site. Secondly an assessment was made
of the usefulness of X-ray Fluorescence Analysis, Inductively
Coupled Plasma Spectrometry and Petrological
analysis to coarse ware studies, using the Pool assemblage
as a case study.
Recording of technological and typological attributes
allowed three phases of Neolithic pottery to be identified.
The earliest phase included sherds of Unstan
Ware. This phase was followed by an assemblage characterised
by pottery with incised decoration, which
was stratified below a traditional Grooved Ware assemblage.
The change in pottery styles and manufacturing
methods with the Grooved Ware indicated that it
evolved elsewhere. Grass tempered and burnished pottery
characterised the Iron Age assemblage.
Pottery samples from all phases of the site were
analysed by XRF and ICPS. In addition, pottery from
late Iron Age sites in the area was analysed for comparison
with the Pool Iron Age pottery. XRF and ICPS
analyses did not distinguish between either different
phases at Pool or different Orcadian sites. This was
attributed to the similarities in geological deposits
over much of Orkney and the variations which can occur
within a clay source.
A clay survey was carried out in the vicinity of the
site, and samples taken for comparison with the Pool
pottery. Identification of rocks and minerals in thin
section, and grain-size analysis, indicated that the
Pool pottery was made locally to the site, and that
both primary and secondary clays were used. It was
concluded that petrological analysis is more suitable
than elemental analysis in the study of coarse wares. / Science-based Archaeology'Committee
of the Science and Engineering Research
Council.
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Trace Elemental Methodologies for the Chromatographic Speciation of Silver Ions and Silver Nanoparticles and the Development of Rice Flour Internal Quality Control Material for Arsenic Speciation Applications using High Performance Liquid ChromatographyHanley, Traci A. 26 May 2017 (has links)
No description available.
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ELEMENTAL SPECIATION BY CHROMATOGRAPHIC SEPARATIONS INTERFACED TO INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRYPAWLECKI-VONDERHEIDE, ANNE MARIE 01 July 2003 (has links)
No description available.
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HIGH PERFORMANCE LIQUID CHROMATOGRAPHIC SEPARATION COUPLED TO INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY FOR ELEMENTAL SPECIATION IN ENVIRONMENTAL SAMPLESSADI, BAKI BILLAH MOHAMMED January 2005 (has links)
No description available.
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INTERFACES FOR LIQUID SAMPLE INTRODUCTION FOR INDUCTIVELY COUPLED PLASMA-MASS SPECTROMETRY AND APPLICATIONS OF ELEMENTAL SPECIATION WITH ICP-MS DETECTION INCLUDING ARSENIC IN APPLES AND SELENIUM IN DIETARY FOOD SUPPLEMENTSB'Hymer, Clayton January 2000 (has links)
No description available.
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Silver Nanoparticle and Silver Ion Water Contamination: Assessment of phytoremediation and point-of-use filtration mediaHanks, Nicole A. January 2015 (has links)
No description available.
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Nanoparticle Characterization, Fundamental Studies and Computer Simulations of Dynamic Reaction Cell Inductively Coupled Plasma Mass SpectrometryGray, Patrick John 21 March 2011 (has links)
No description available.
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