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Možnosti určení původu vína z prvkového složení / Possibilities of determining the origin of the wine from the element compositionŠkařupa, Přemysl January 2012 (has links)
The aim of this diploma thesis was to evaluate the possibility of determining the origin of the wine on the basis of elemental composition. For this purpose an analysis of major and minor elements was accomplished in selected varieties of wines. In total, 48 parameters for six wine subregions in Bohemia and Moravia was determined and used. The sum of 35 parameters represented the concentration of selected elements and other 13 parameters were created from the measured values. The concentration of elements was determined by inductively coupled plasma mass spectrometry (ICP-MS). For the purpose of classification of samples into groups multivariate statistical methods were used. The measured data set was firstly separated using analysis of variance (ANOVA) and discriminant analysis (DA). It has been proved that the selected variables influence the distribution of wines into categories according to their geographic location. Canonical discriminant analysis, principal component analysis (PCA) and cluster analysis has been used for graphical projection. Simultaneously the model based on our analysis was created to enable classify an unknown sample of wine according to the origin.
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Building a Database with Background Equivalent Concentrations to Predict Spectral Overlaps in ICP-MSLiu, Fang 18 May 2017 (has links)
No description available.
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Development of laser micro-sampling and electrothermal vaporization techniques for ICP-mass spectrometry and its cosmochemical implications on opaque assemblages in chondrites / ICP質量分析法を用いた微量元素同位体分析に向けたレーザー局所サンプリング法および電気加熱気化法の開発とその宇宙化学物質への応用Okabayashi, Satoki 24 March 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第18086号 / 理博第3964号 / 新制||理||1571(附属図書館) / 30944 / 京都大学大学院理学研究科地球惑星科学専攻 / (主査)教授 平田 岳史, 教授 田上 高広, 准教授 三宅 亮 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
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RELEASE OF MICRO- AND NANOSCALE PLASTICS FROM SYNTHETIC TEXTILES DURING LAUNDRY AND QUANTIFICATION OF NANOSCALE PLASTICS BY SINGLE PARTICLE INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRYMahbub, Md Shahriar 01 May 2022 (has links)
Plastic wastes released in the environment can produce microplastics (MPs, Size < 5 mm) and nanoscale plastics (NPs, Size < 100 nm) due to the environmental weathering processes. The presence of the MPs and NPs have been found worldwide in different aquatic and terrestrial environments. These tiny plastics have detrimental health impacts when they are ingested or inhaled by aquatic organisms as well as human beings. However, their occurrences including identification and quantification in the environment are still a great challenge. Particularly, quantification for NPs is a challenge, as there is no standard technique available yet that can count the NPs effectively. Therefore, this thesis was focused on two important aspects related to microplastics (MPs) and nanoscale plastics (NPs). Firstly, assess the source of MPs or NPs release and secondly, NPs quantification. Microfibers (MFs) are one of the most abundant portions of MPs in the aquatic environment, which are shed during the washing and drying of fabrics. Hence, in the first area of the study, the release pattern of MPs, in the form of acrylic MFs from portable washer and dryer during fabric washing and drying under different conditions were investigated. Additionally, the subsequent degradations behavior of these released MFs under ultraviolet light (UV-A) irradiation were explored. The results indicated that the MFs were released almost 2 times higher when the fabrics were washed for 60 min compared to 30 min due to higher mechanical stresses. In addition, MFs released were increased by 1.4 times higher when the fabrics were dried for 60 min compared to 30 min due to longer rotational forces on the fabrics. The use of detergent during washing promoted 2.7 times more MF release compared to without detergent. Moreover, MFs were released approximately 1.8 times higher from washing when washed with 40°C of water than with 20°C of water. However, subsequent washing cycles showed decreasing patterns of MF releases during washing and drying, approximately 45% less and 67% less, respectively in the 7th wash compared to the 1st wash as the fabrics approach a plateau. The released acrylic MFs were analyzed after their exposure to UV-A irradiation in the aquatic environment from 0 day to 182 days. After 182 days of UV-A irradiation, released acrylic MFs showed significant changes in the surface morphology in the form of cracks, holes, and flakes determined by scanning electron microscope (SEM). The formations of cracks, cavities, and flakes in the MF’s surface were proportional to the period of UV-A exposure. Dimensions of the formed holes and cracks on the UV-A degraded MFs suggested that MFs can turn into NPs in presence of water and UV-A exposure in the environment. Hence, a robust analytical tool must be optimized to detect these tiny degraded NPs in the aquatic environment. This brings to the second area of the study which aimed to optimize and validate a method to detect NPs through coating with synthesized gold nanoparticles (AuNPs) by Single Particle Inductively Coupled Plasma Mass Spectrometry (SP-ICP-MS). This study successfully detected the polystyrene nanoscale plastics (PS NPs, size 61 nm) by particle-by-particle analysis in single quadrupole-based SP-ICP-MS and the detection limit of particle number concentration was reached up to 8.64 × 10^7 particles/L. PS NPs were selected as a model nanoscale plastic as it is one of the most abundant plastics in the environment. The method was applied to PS NPs in deionized (DI) water which achieved a good amount of PS NP recoveries by up to 98%. This analytical technique can be further optimized and might be helpful for analyzing NPs in any environmental samples to determine their occurrences and concentrations.
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Development and Application of a Method for Determination of Metals in Environmental SedimentsNguyen, Tuong Van 04 May 2023 (has links)
No description available.
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A Microanalytical Approach to Understanding the Origin of Cumulate Xenoliths from Mauna Kea, HawaiiPickard, Megan 08 August 2008 (has links) (PDF)
Cumulate xenoliths erupted with alkalic hawaiite lavas from a postshield cinder cone on Mauna Kea, Hawaii include a variety of mafic and ultramafic rock types. Previous studies of major and trace element compositions of minerals in the xenoliths are interpreted to show transitional to alkalic magma parentages from the postshield stage, although any orthopyroxene-bearing xenoliths are considered to have tholeiitic parents. Major element compositions minerals were analyzed using the electron microprobe and trace element compositions of clinopyroxene grains were analyzed by laser ablation inductively coupled plasma mass spectrometry. In this study, major element compositions of clinopyroxene, olivine and plagioclase grains and trace element compositions in clinopyroxene grains in xenoliths lacking orthopyroxene indicate a transitional magma parentage consistant with postshield magmas. Trace element compositions of possible parent magmas of the xenoliths were calculated from clinopyroxene compositions using partition coefficients for basaltic liquids from Hauri et al. (1994). Liquids calculated from the clinopyroxene in the xenoliths were compared to Mauna Kea shield lavas and to the postshield Hamakua and Laupahoehoe units. Chondrite-normalized rare earth element (REE) patterns of liquids calculated from both orthopyroxene-bearing xenoliths and those without orthopyroxene were similar REE patterns of both Mauna Kea postshield tholeitic and alkalic lavas. Liquids from a wehrlite and an olivine gabbronorite have REE patterns similar to tholeiitic shield basalts. To better distinguish the transitional xenolith sources as one of Mauna Kea's two postshield substages, the older, basaltic Hamakua unit or the younger hawaiitic Laupahoehoe unit, variation diagrams compared calculated liquid compositions to Mauna Kea lavas from the shield and postshield stages. Calculated liquid trace element concentrations are similar to those of Hamakua lavas.
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Dinosaurian Faunas of the Cedar Mountain Formation and LA-ICP-MS Detrital Zircon Ages for Three Stratigraphic SectionsMori, Hirotsugu 23 November 2009 (has links) (PDF)
The Cedar Mountain Formation contains the most diverse record of Early Cretaceous dinosaurs in the western hemisphere. However, analyses of its faunas have been hindered because 1) most taxa are based on incomplete/fragmentary materials or incomplete descriptions, 2) most sites and some horizons preserve few taxa, and 3) the stratigraphy and geochronology are poorly understood. To help resolve these stratigraphic and correlation problems U-Pb LA-ICP-MS detrital zircon ages were obtained at significant sites and horizons. These dates indicate all sites at or near the base of the formation are no older than 122 to 124 Ma, thus all basal stratigraphic packages are time equivalent. Detrital zircons coarsely bracket the temporal span of the Ruby Ranch Member between about 115 Ma to 111 Ma while the base of the Mussentuchit Member is dated between 108 to 104 Ma and the top of the member is Cenomanian in age. Multivariate analyses utilizing Simpson and Raup-Crick similarity index and pair-group moving algorithms reveal that formationfs faunas fall into two groups. These groups are compared statistically with European, Asian, and Morrison faunas. Results indicate (1) that there is no close relationship between the Yellow Cat fauna and the Morrison Formation fauna and (2) corroborate long-standing hypotheses that the Yellow Cat fauna has European ties and the Mussentuchit fauna has Asian ties. Detrital zircon LA-ICP-MS U-Pb ages were used in this study to approximate the time of deposition of strata because volcanic ashes are rarely preserved in the formation. The ability to select the youngest crystals in a sample prior to applying analytical methods could substantially reduce the number of crystals and cost required to obtain these dates. To this end, the hypothesis that the most pristine, unabraded crystals should be younger than abraded crystals was tested by imaging detrital zircons via SEM, ranking the crystals by the degree of abrasion, and determining their ages. Results of this study partly corroborate the hypothesis in that there is a correlation between the degree of abrasion and ages – obviously abraded crystals are most likely the oldest while pristine to slightly abraded crystals are usually the youngest in a given sample.
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Ion Transport Behaviors Upstream and Downstream from the Sampling Cone of an Inductively Coupled Plasma Mass SpectrometerMa, Haibin 09 July 2009 (has links) (PDF)
Inductively coupled plasma - mass spectrometry (ICP-MS) is the technique of choice worldwide for trace elemental determinations because of its excellent ionization ability, low detection limits and fast analysis speeds. However, the ICP-MS still suffers from some disadvantages, such as spectral overlap and severe matrix effects. Matrix effects or interferences, partly arise from changes in the analyte transmission through the interfacial region between the ICP and mass spectrometer with changes in sample matrix. Better understanding of the transmission behaviors of analyte through the sampling and skimmer cones will provide the insights needed to alleviate matrix interferences and to improve the interface design between the ICP and mass spectrometer. Laser induced fluorescence is a highly sensitive, non-invasive and element specific detection method. The research herein endeavors to explain the transport behaviors of analytes upstream and downstream from the sampling cone in an ICP-MS. The final goal of this research is to improve the consistency and efficiency with which ions are transported from an ICP source to a mass analyzer. Several issues related to analyte transmission through the sampling and skimmer cones have been explored and discussed in this dissertation. First, it is found that the existence of the sampling cone not only disturbs the local thermodynamic equilibrium of the plasma, but also changes the spatial distributions and number densities of analyte species. Second, it has been verified that the spread of analyte species in the first vacuum stage is mass-dependent and can be explained by ambiploar diffusion theory. Finally, the current research suggests that the transmission efficiencies of the skimmer cone are impacted by the nebulizer flow and first vacuum stage pressure of the ICP-MS. To better elucidate the analyte transport behaviors from the plasma to the ion detector in an ICP-MS, more investigation needs to be carried out. Further research, such as the entire measurements of analyte transmission efficiency through the skimmer cone, the variation of doubly charged ions under different plasma operational conditions, and the functions of argon metastable atoms on analyte ionization inside the plasma will require much additional work.
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Laser-Induced Fluorescence Imaging of Calcium and Barium Ion Beams in the Second Vacuum Stage of a Commercial Inductively Coupled Plasma Mass SpectrometerEdmund, Alisa Jane 24 June 2014 (has links) (PDF)
Inductively coupled plasma-mass spectrometers (ICP-MS) have become the workhorses of many analytical labs over the past few decades. Despite the instruments' high sensitivities and low detection limits there is still a demand for improvements in several aspects of their performance. One area of improvement is in the understanding of "space charge effects" Space charge effects are classified as problems associated with the ion beam. Problems are created when the mutual repulsions of the ions make consistent focusing of the ion beam difficult. This is particularly problematic with samples containing a low concentration analyte contained within a high salt solution matrix, resulting in lower instrument sensitivity and inaccurate results. The research presented here used laser-induced fluorescence (LIF) imaging to characterize the ion beam as it enters the mass analyzer of a commercial ICP-MS. To perform the LIF imaging a laser system with two ring cavities was constructed to frequency double a CW titanium-sapphire laser to the calcium ion transition at 393.4 nm or to the barium ion transition at 455.4 nm. Ion beam images for both elements were taken under different instrument modes and matrix compositions. The same trends in shift and distortion of the barium ion beam with the addition of a lead matrix was observed as in previous experiments with calcium. A shift in the focal point of the ion beams of both elements was also observed in normal sensitivity mode and with the instrument's collisional reaction interface (CRI). This work indicates that a shift in beam focusing is responsible for the change in ion transmission due to changes in matrix composition and instrument modes.
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Discrimination Of Forensic Trace Evidence Using Laser Induced Breakdown SpectroscopyBridge, Candice 01 January 2007 (has links)
Elemental analysis in forensic laboratories can be tedious and many trace evidence items are not analyzed to determine their elemental composition. Presently, scanning electron microscopy-energy dispersive x-ray spectroscopy (SEM-EDS) is the primary analytical tool for determining the elemental composition of trace evidence items. However, due to the time it takes to obtain the required vacuum and the limited number of samples that can be analyzed at any one time, SEM-EDS can be impractical for a high volume of evidence items. An alternative instrument that can be used for this type of analysis is laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). While LA-ICP-MS is a very precise and quantitative analytical method that determines elemental composition based on isotopic mass measurements; however, the instrumentation is relatively expensive and therefore is budgetarily prohibitive for many forensic laboratories. It is the purpose of this research to evaluate an inexpensive instrument that can potentially provide rapid elemental analysis for many forensic laboratories. Laser induced breakdown spectroscopy (LIBS) is an analytical method that meets these requirements and offers information about the elemental composition based on ionic, atomic and diatomic molecular emissions.
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