The Experts below are selected from a list of 264 Experts worldwide ranked by ideXlab platform
Kazuyoshi Tsukamoto - One of the best experts on this subject based on the ideXlab platform.
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Steady-state Surface Concentration profiles of primary ion species during secondary ion mass spectrometry measurements
Applied Surface Science, 2003Co-Authors: Sumikazu Yoshikawa, H. Morita, Fumiyo Toujou, Toshiyuki Matsunaga, Kazuyoshi TsukamotoAbstract:Abstract The steady-state Surface Concentration profiles of Cs ions during secondary ion mass spectrometry (SIMS) measurements were investigated in details for Si using low-energy oxygen primary ion bombardment. Depending on the bombardment conditions of Cs primary ions, there are shoulder regions or transient regions under the sputtered Surface where Si secondary ion intensities are lower than those at bulk region. To achieve accurate depth profiling with minimum transient region using Cs primary ions, it is necessary to choose bombardment conditions such that primary ion energy is below 1 keV or large angle of incidence over 80° will be needed for higher primary ion energy.
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Surface Concentration of primary ion species and its effect to depth profiling in SIMS analyses
Extended Abstracts of the Second International Workshop on Junction Technology. IWJT. (IEEE Cat.No.01EX541C), 2001Co-Authors: Sumikazu Yoshikawa, Kazuyoshi TsukamotoAbstract:In Secondary Ion Mass Spectrometry (SIMS), the presence of primary ions on the sputtering Surface is considered to enhance the secondary ion yields. In this work, the Surface Concentration profiles of Cs primary ions were investigated in details for Si using low energy oxygen primary ion bombardment in order to achieve accurate depth profiling with Cs primary ions.
Koiti Araki - One of the best experts on this subject based on the ideXlab platform.
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Key role of Surface Concentration on reproducibility and optimization of SERS sensitivity
Journal of Raman Spectroscopy, 2017Co-Authors: Jonnatan J. Santos, Sérgio Hiroshi Toma, Paola Corio, Koiti ArakiAbstract:A systematic study was carried out demonstrating that Surface Concentration is the key factor that must be controlled to overcome the reproducibility problems that has long been haunting Surface enhanced Raman spectroscopy (SERS), converting it in a quantitative analytic tool without using any internal standard. The 1,10-phenanthroline molecule (phen) used as model compound can assume different orientations on the Surface as a function of Surface Concentration, but a linear response as a function of Concentration was realized in a well-defined range of gold nanoparticles (AuNPs) and phen Concentration ratios, allowing to fully explore the very high sensitivity of SERS technique. A detection at a low Concentration (5.0 × 10−8 mol dm−3) was achieved controlling the Surface Concentration in the optimum range where the signals of the species of analytic interest are maximized whilst the signals of all other species are minimized. Copyright © 2017 John Wiley & Sons, Ltd.
Sumikazu Yoshikawa - One of the best experts on this subject based on the ideXlab platform.
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Steady-state Surface Concentration profiles of primary ion species during secondary ion mass spectrometry measurements
Applied Surface Science, 2003Co-Authors: Sumikazu Yoshikawa, H. Morita, Fumiyo Toujou, Toshiyuki Matsunaga, Kazuyoshi TsukamotoAbstract:Abstract The steady-state Surface Concentration profiles of Cs ions during secondary ion mass spectrometry (SIMS) measurements were investigated in details for Si using low-energy oxygen primary ion bombardment. Depending on the bombardment conditions of Cs primary ions, there are shoulder regions or transient regions under the sputtered Surface where Si secondary ion intensities are lower than those at bulk region. To achieve accurate depth profiling with minimum transient region using Cs primary ions, it is necessary to choose bombardment conditions such that primary ion energy is below 1 keV or large angle of incidence over 80° will be needed for higher primary ion energy.
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Surface Concentration of primary ion species and its effect to depth profiling in SIMS analyses
Extended Abstracts of the Second International Workshop on Junction Technology. IWJT. (IEEE Cat.No.01EX541C), 2001Co-Authors: Sumikazu Yoshikawa, Kazuyoshi TsukamotoAbstract:In Secondary Ion Mass Spectrometry (SIMS), the presence of primary ions on the sputtering Surface is considered to enhance the secondary ion yields. In this work, the Surface Concentration profiles of Cs primary ions were investigated in details for Si using low energy oxygen primary ion bombardment in order to achieve accurate depth profiling with Cs primary ions.
Arturo Trejo - One of the best experts on this subject based on the ideXlab platform.
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Prediction of the Surface tension, Surface Concentration, and the relative Gibbs adsorption isotherm of binary liquid systems
Fluid Phase Equilibria, 2006Co-Authors: Luis Felipe Ramírez-verduzco, Ascención Romero-martínez, Arturo TrejoAbstract:Abstract Calculation results for Surface tension, Surface Concentration, and the relative Gibbs adsorption isotherm of binary systems, as a function of Concentration and temperature, were obtained using a formal thermodynamic model, which includes the activity coefficients for both, the bulk and the Surface layer. To take into account the non-ideality of the liquid bulk as well as that of the Surface layer, the UNIFAC group contribution activity coefficient model, with binary interaction parameters derived from vapor–liquid equilibrium data and reported previously in the open literature, is also used. The calculation method used to derive the mixture Surface tension and Surface Concentration, makes an analogy between pressure and vapor Concentration from a traditional isothermal liquid–vapor bubble point calculation and the Surface tension and Surface Concentration, as used here. Values for the Surface tension of 31 binary systems, at different temperatures, covering the full Concentration range, which makes a total of 105 different binary systems, were estimated. Simultaneously, values for the Surface Concentration for the same binary systems were also calculated, which in turn were used to derive values of the relative Gibbs adsorption isotherm, employing a new scheme proposed in this work. The binary systems included in this study, have representatives from different chemical species which include polar, non-polar, and associating compounds. The average relative percent error obtained from the comparison of experimental and calculated Surface tension values for the 790 points considered was 2.88%, which leads to establish that the model, together with the calculation scheme here proposed are accurate to reproduce the Concentration and temperature dependence of the Surface tension.
Francisco Vicente - One of the best experts on this subject based on the ideXlab platform.
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Calculation of the Surface Concentration of Zn(I) from the anodic voltammetric peak of zinc combined with the QCM results
Electrochemistry Communications, 2004Co-Authors: David Giménez-romero, José Juan García-jareño, Francisco VicenteAbstract:Deconvolution of voltammograms of anodic dissolution of zinc has proved to be possible through the electrochemical quartz crystal microbalance data and the F(dm/dQ) function. This deconvolution allows to calculate the Surface Concentration of Zn(I) and to obtain an estimation for the kinetic constant of the second single-electron transfer.
