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Showing 1 to 20 of 71 for “"Chemical elements"”.

  1. Scientific Realism and the Periodic Table of Chemical Elements

    The periodic table poses a difficulty for both scientific realists and anti-realists. The anti-realist has difficulty accounting for the success of the table during a period in chemistry when many theories and concepts changed; the spatial relations of current tables in use do not show fundamental …

    vt Repository record for Scientific Realism and the Periodic Table of Chemical Elements (opens in a new tab)

  2. Analysis of Chemical Elements in Basalts using Mislabeled Data, a Machine Learning Approach

    … tectonic settings. There are well-known chemical elements used to classify tectonic settings. An exploration of new features is done using Logistic Regression and Random Forest to discover any new elements of interest. The models were used with other tools, such as recursive feature …

    cuny Repository record for Analysis of Chemical Elements in Basalts using Mislabeled Data, a Machine Learning Approach (opens in a new tab)

  3. Values in Action: Simplicity, Completeness, and Carefulness in the Development of the Systematisations of Chemical Elements

    … when developing their systematisations of the chemical elements in 1863-1875. While no chemist emphasised just one value in the course of establishing of their systematisations, I argue that Newlands elevated simplicity (“simple relation”), Mendeleev completeness (polnost’), and Meyer …

    cambridge Repository record for Values in Action: Simplicity, Completeness, and Carefulness in the Development of the Systematisations of Chemical Elements (opens in a new tab)

  4. Quantification of the bioccumulation potential of various chemical elements from coal fly ash using Brassia juncea and Spinacia oleracea L and its implication for phytoremediation of coal fly ash dumps

    … investigation focuses on the examination of the chemical elements bioaccumulation and phytoremediation potential of Indian mustard (Brassica juncea) and Spinach (Spinacia Oleracea L). X-ray fluorescence (XRF) was used to analyze the elemental composition of FA and soil, Scanning Electron …

    venda Repository record for Quantification of the bioccumulation potential of various chemical elements from coal fly ash using Brassia juncea and Spinacia oleracea L and its implication for phytoremediation of coal fly ash dumps (opens in a new tab)

  5. Sunkieji metalai Vilniaus miesto sporto aikščių grunte /

    … Two background level sets of the determined chemical elements were calculated for soils classified according grain-size analysis and geological data extracted from the Quaternary geological map of Vilnius. The obtained results revealed that Zn, Pb, Cu, Ag and Sn contaminate soils of some …

    vilnius Repository record for Sunkieji metalai Vilniaus miesto sporto aikščių grunte / (opens in a new tab)

  6. Neutron exposure and neutron flux in Asymptotic Giant Branch stars: a study of neutron capture cross sections of Zr isotopes

    … aims to understand the origin of the chemical elements and the energy generation in stars. This work concerns the measurements of the neutron capture cross sections of 90,91,92,93,94,96Zr isotopes, performed at the time-of-flight facilities n_TOF at CERN and GELINA at IRMM and their …

    ghent Repository record for Neutron exposure and neutron flux in Asymptotic Giant Branch stars: a study of neutron capture cross sections of Zr isotopes (opens in a new tab)

  7. Computer modelling of the chemical speciation in seawater

    … thesis is to establish a computer model of the chemical elements in seawater and to use this model to gain insight into the chemical processes controlling dissolution, precipitation, redox levels and coordinative interactions in surface seawater. In order to accomplish this task a relatively …

    cape-town Repository record for Computer modelling of the chemical speciation in seawater (opens in a new tab)

  8. Estudo de Diplodon (D.) Besckeanus (Dunker, 1849) existente na Lagoa de Juturnaíba, município de Araruama, Estado do Rio de Janeiro, Brasil (Bivalvia, Unionoidea, Hyriidae)

    … observations on behavior are added. Physical and chemical data with regard to the biotope were taken from just one point. This sampling was done preferably once in each season lasting for twenty four hours. A check list of associated fauna and flora (observed or colleted) , the results of the …

    brazil-uerj Repository record for Estudo de Diplodon (D.) Besckeanus (Dunker, 1849) existente na Lagoa de Juturnaíba, município de Araruama, Estado do Rio de Janeiro, Brasil (Bivalvia, Unionoidea, Hyriidae) (opens in a new tab)

  9. The Space of Construction: Elemental Prefabrication

    … This thesis sets out to form a set of basic elements for a minimum house in light of this question that is both functional and aesthetic. The goal is to develop an efficient prefabricated system of construction analogous to a chart of chemical elements. The modular system is then applied to …

    vt Repository record for The Space of Construction: Elemental Prefabrication (opens in a new tab)

  10. Chemical composition study of Galactic stellar substructures /

    … main atmospheric parameters and abundances of 21 chemical elements have been determined. The abundance pattern of programe stars has similar characteristics to those of the Galactic thick disc, which might suggest that their formation histories are linked. We compare our results with other …

    vilnius Repository record for Chemical composition study of Galactic stellar substructures / (opens in a new tab)

  11. Don't Take My Kodachrome Away! Eastman Kodak and the Loss of System Control in the Digital Era

    … technological, based as it is on intricate chemical processes. George Eastman famously created the conventional photographic system, making the technology widely available to a mass market. Using the systems approach, I show how the Eastman Kodak Company consolidated critical photographic …

    vt Repository record for Don't Take My Kodachrome Away! Eastman Kodak and the Loss of System Control in the Digital Era (opens in a new tab)

  12. Tropical climate variability from the last glacial maximum to the present

    … region are determined using both organic geochemical techniques and climate modeling. Upwelling in Cariaco Basin is reconstructed using chlorin steryl esters as proxies for phytoplankton community structure. We find that the diatom population was larger during the Younger Dryas cold event, …

    woods-hole Repository record for Tropical climate variability from the last glacial maximum to the present (opens in a new tab)

  13. Mechanisms of metal release from contaminated coastal sediments

    The fate of trace metals in contaminated coastal sediments is poorly understood, yet critical for effective coastal management. The aim of this thesis is to investigate and quantify the mechanisms leading to the release of silver, lead and copper across the sediment-water interface. Two contrasting …

    woods-hole Repository record for Mechanisms of metal release from contaminated coastal sediments (opens in a new tab)

  14. Effects of convection and non-equilibrium radiation transfer in stellar atmospheres /

    … on the formation of spectral lines of different chemical elements in the atmospheres of different metallicity main sequence turn-off (MSTO) and red giant branch (RGB) stars. The influence of convection is assessed by analyzing differences in the elemental abundances obtained by using 3D …

    vilnius Repository record for Effects of convection and non-equilibrium radiation transfer in stellar atmospheres / (opens in a new tab)

  15. The Legacy of the First Galaxies: Exploring Ancient Stars in the Milky Way

    … insight into early galaxy formation and chemical enrichment. Currently, though, accreted UFDs are poorly understood and we lack ways to identify stars that accreted from UFDs. By utilizing a simulation suite of 35 Milky Way-mass galaxies forming, I find that chemical tagging with …

    mit Repository record for The Legacy of the First Galaxies: Exploring Ancient Stars in the Milky Way (opens in a new tab)

  16. Machine Learning Force Fields for Molecular Chemistry

    … simultaneous description of a large number of chemical elements. Next, multi-ACE is proposed, which provides a unifying theory of most classical and machine learning force fields. Using the design space set out in this theory, a new method, called MACE is created. MACE is shown to provide …

    cambridge Repository record for Machine Learning Force Fields for Molecular Chemistry (opens in a new tab)

  17. Desalination of Produced Water via Gas Hydrate Formation and Post Treatment

    … as functions of %Reduction of difference chemical elements, CO? requirements and applied T and P conditions. The impact of dewatering techniques, including centrifuge and filtration process, on gas hydrate solid product is studied. The results showed that over 99% of dissolved NaCl and …

    vt Repository record for Desalination of Produced Water via Gas Hydrate Formation and Post Treatment (opens in a new tab)

  18. Suitability of Thulamela Clays for Use in The Ceramic Industry: A Case Study in Thulamela Municipality, Limpopo Province, South Africa

    … applications by examining their physical, chemical, and mineralogical properties. A comprehensive analysis was conducted using various tests, including particle size analysis, Atterberg limits, X-ray fluorescence (XRF), and X-ray diffraction (XRD). The study evaluated the clays' strength, …

    venda Repository record for Suitability of Thulamela Clays for Use in The Ceramic Industry: A Case Study in Thulamela Municipality, Limpopo Province, South Africa (opens in a new tab)

  19. Analysis of Factors Controlling the Distribution of Trace Elements in Surface Sediments of Coastal Alabama

    … and the extractable concentrations of 28 chemical elements (Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Ni, Pb, Se, Si, Sb, Ag, Na, Sn, Sr, Ti, Tl, V, and Zn). The main minerals found via Rietveld refinement of XRD patterns in these samples were quartz, illite, kaolinite, …

    alabama Repository record for Analysis of Factors Controlling the Distribution of Trace Elements in Surface Sediments of Coastal Alabama (opens in a new tab)

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