The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

Wurzp. - One of the best experts on this subject based on the ideXlab platform.

  • A New Method and Mass-Spectrometric Instrument for Extraterrestrial Microbial Life Detection Using the Elemental Composition Analyses of Martian Regolith and Permafrost/Ice
    Astrobiology, 2017
    Co-Authors: Wurzp.
    Abstract:

    Abstract We propose a new technique for the detection of microorganisms by Elemental Composition analyses of a sample extracted from regolith, permafrost, and ice of extraterrestrial bodies. We also describe the design of the ABIMAS instrument, which consists of the onboard time-of-flight laser mass-reflectron (TOF LMR) and the sample preparation unit (SPU) for biomass extraction. This instrument was initially approved to fly on board the ExoMars 2020 lander mission. The instrument can be used to analyze the Elemental Composition of possible extraterrestrial microbial communities and compare it to that of terrestrial microorganisms. We have conducted numerous laboratory studies to confirm the possibility of biomass identification via the following biomarkers: P/S and Ca/K ratios, and C and N abundances. We underline that only the combination of these factors will allow one to discriminate microbial samples from geological ones. Our technique has been tested experimentally in numerous laboratory trials on ...

Kostya Ostrikov - One of the best experts on this subject based on the ideXlab platform.

  • control of core shell structure and Elemental Composition of binary quantum dots
    Applied Physics Letters, 2007
    Co-Authors: Igor Levchenko, Amanda E Rider, Kostya Ostrikov
    Abstract:

    The possibility of initial stage control of the Elemental Composition and core/shell structure of binary SiC quantum dots by optimizing temporal variation of Si and C incoming fluxes and surface temperatures is shown via hybrid numerical simulations. Higher temperatures and influxes encourage the formation of a stoichiometric outer shell over a small carbon-enriched core, whereas lower temperatures result in a larger carbon-enriched core, Si-enriched undershell, and then a stoichiometric SiC outer shell. This approach is generic and is applicable to a broad range of semiconductor materials and nanofabrication techniques.

  • control of core shell structure and Elemental Composition of binary quantum dots
    Science & Engineering Faculty, 2007
    Co-Authors: Igor Levchenko, Amanda E Rider, Kostya Ostrikov
    Abstract:

    The possibility of initial stage control of the Elemental Composition and core/shell structure of binary SiC quantum dots by optimizing temporal variation of Si and C incoming fluxes and surface temperatures is shown via hybrid numerical simulations. Higher temperatures and influxes encourage the formation of a stoichiometric outer shell over a small carbon-enriched core, whereas lower temperatures result in a larger carbon-enriched core, Si-enriched undershell, and then a stoichiometric SiC outer shell. This approach is generic and is applicable to a broad range of semiconductor materials and nanofabrication techniques. © 2007 American Institute of Physics.

Eliziane Luiza Benedetti - One of the best experts on this subject based on the ideXlab platform.

  • Elemental Composition of yerba mate ilex paraguariensis a st hil under low input systems of southern brazil
    Science of The Total Environment, 2020
    Co-Authors: Antonio Carlos Vargas Motta, Julierme Zimmer Barbosa, Ederlan Magri, Guilherme Quaresma Pedreira, Delmar Santin, Stephen A Prior, Rangel Consalter, Scott D Young, Martin R Broadley, Eliziane Luiza Benedetti
    Abstract:

    Abstract Elemental Composition of food can be used to determine nutritional potential as well as guiding legislation for establishing maximum acceptable limits (MAL) of metals in consumption products. This study aimed to determine the Elemental background levels of yerba mate (Ilex paraguariensis A.St.-Hil.) under varied geologic formations in southern Brazil. Mature leaves were randomly collected from four wild-grown plants at thirty native sites in three states and analyzed for 32 elements. Since yerba mate is not washed to obtain the final product, leaves were analyzed with and without washing to assess foliar deposition. Concentration values of As, Ag, Be, Cs, Cr, Li, Se, Tl, U, and V were near detection limits, indicating low potential as a source and/or toxicity to the consumer. Washing decreased concentrations of Fe, Ti, As, Mo, Li, V, and Pb, suggesting atmospheric contributions/dust deposition. Concentrations of Mn (very high), Zn (high), and Ni (high) demonstrated that leaves could be an important source of these elements. Soil parent material affected Elemental Composition with basalt providing higher concentrations of Mn, P, and Co while Rhyodacite provided higher concentrations of K and Na. All samples exhibited Pb values below the MAL of 0.6 mg kg−1, but 23% of washed leaves and 20% of unwashed leaves had Cd concentrations close to or above the MAL value of 0.4 mg kg−1. Study results indicated that Cd MAL values for yerba mate in southern Brazil should be reassessed.

Wenying Li - One of the best experts on this subject based on the ideXlab platform.

  • prediction of Elemental Composition of coal using proximate analysis
    Fuel, 2017
    Co-Authors: Lan Yi, Jie Feng, Wenying Li
    Abstract:

    Abstract Ultimate analysis is an important property for fuel utilization. The experimental determination of ultimate analysis is sophisticated, long time consumed, and expensive, on the contrary, the proximate analysis can be run rapidly and easily. A variety of correlations to predict the ultimate analysis of biomass using the proximate analysis have been appeared, while there exists a few number of correlations to estimate the Elemental Compositions of coal using proximate analysis in the literature but were focused on the predicted model or dependent on the heating value of coal. According to the proximate analysis of four different ranks of coal, this study proposes a series of correlations which are classified to predict carbon, hydrogen, and oxygen Compositions through using 300 data points and validated further by another set of 40 data points. These correlations have the R2 of 0.95, 0.91, and 0.65 corresponding to the measured contents of C, H, and O in anthracite, 0.93, 0.83, and 0.67 of C, H, and O in high-rank bituminous, 0.86, 0.61, and 0.71 of C, H, and O in subbituminous, and 0.92, 0.67, and 0.66 of C, H, and O in lignite, respectively. The main merit of the correlations is the ability to estimate Elemental Composition of different rank coals using the proximate analysis and thus offers a valuable tool to set up a coal-thermal-conversion-process model.

Mykhailo Ya Valakh - One of the best experts on this subject based on the ideXlab platform.

  • Direct Determination of 3D Distribution of Elemental Composition in Single Semiconductor Nanoislands by Scanning Auger Microscopy
    Nanoscale Research Letters, 2016
    Co-Authors: Semyon S Ponomaryov, Volodymyr O Yukhymchuk, P M Lytvyn, Mykhailo Ya Valakh
    Abstract:

    An application of scanning Auger microscopy with ion etching technique and effective compensation of thermal drift of the surface analyzed area is proposed for direct local study of Composition distribution in the bulk of single nanoislands. For Ge_xSi_1 − x-nanoislands obtained by MBE of Ge on Si-substrate gigantic interdiffusion mixing takes place both in the open and capped nanostructures. Lateral distributions of the Elemental Composition as well as concentration-depth profiles were recorded. 3D distribution of the Elemental Composition in the d-cluster bulk was obtained using the interpolation approach by lateral Composition distributions in its several cross sections and concentration-depth profile. It was shown that there is a germanium core in the nanoislands of both nanostructure types, which even penetrates the substrate. In studied nanostructures maximal Ge content in the nanoislands may reach about 40 at.%.

  • direct determination of 3d distribution of Elemental Composition in single semiconductor nanoislands by scanning
    2016
    Co-Authors: Semyon S Ponomaryov, Volodymyr O Yukhymchuk, P M Lytvyn, Mykhailo Ya Valakh
    Abstract:

    An application of scanning Auger microscopy with ion etching technique and effective compensation of thermal drift of the surface analyzed area is proposed for direct local study of Composition distribution in the bulk of single nanoislands. For GexSi1� x-nanoislands obtained by MBE of Ge on Si-substrate gigantic interdiffusion mixing takes place both in the open and capped nanostructures. Lateral distributions of the Elemental Composition as well as concentration-depth profiles were recorded. 3D distribution of the Elemental Composition in the d-cluster bulk was obtained using the interpolation approach by lateral Composition distributions in its several cross sections and concentration-depth profile. It was shown that there is a germanium core in the nanoislands of both nanostructure types, which even penetrates the substrate. In studied nanostructures maximal Ge content in the nanoislands may reach about 40 at.%.