Analytical optimization of exponent values in protonic and deuteronic Gaussian‐type functions by elimination of translational and rotational motions from multi‐component molecular orbital scheme

To optimize the exponent values in protonic and deuteronic Gaussian‐type functions (GTF) by the elimination of translational and rotational motions, we have proposed the new scheme of an analytical gradient formula with respect to the exponent values in the multi‐component molecular orbital scheme, which can take into account the quantum effects of protons and deuterons, under the Hartree‐Fock level of theory. Numerical assessment of H₂ and D₂ molecules confirms that there is a clear difference between distributions of protonic and deuteronic orbitals following the elimination of translational and rotational motions. In particular, the d‐type GTF in the protonic orbital drastically improves the total energy. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008     

Baseline noise and measurement uncertainty in liquid chromatography.

The stochastic properties of baseline noise in HPLC systems with a UV photo-diode array, photo-multiplier and gamma-ray detector were examined by dividing the noise into auto-correlated random process (Markov process) and an independent process (white noise). The present work focused on the effect of the stochastic noise properties on a theoretical estimation of the standard deviation (SD) of area measurements in instrumental analyses. An estimation theory, called FUMI theory (Function of Mutual Information), was taken as an example. A computer simulation of noise was also used. It was shown that the reliability (confidence intervals) of theoretical SD estimates mainly depends on the following factors: the ratio of the white noise and Markov process occurring in the baselines; the number of data points used for the estimation; the width of a target peak for which the SD is estimated.     

Pressure induced insulator-metal transition in quasi one-dimensional niobium tetraiodide

The resistivity of a quasi one-dimensional semiconductor NbI₄ was measured at high pressures. The resistivity decreased monotonously with increasing pressure. The activation energy of 0.12 eV at atmospheric pressure decreased to 0.06 eV at 100 kbar and to 0.02 eV at 130 kbar. The temperature coefficient of resistivity becomes positive at about 150 kbar.     

Spectra and emission lifetimes of H2CS(Ã 1A2)

Fluorescence spectra and lifetimes of single vibronic levels of the first excited singlet state of H₂CS have been measured under effusive flow conditions. Fluorescence lifetimes of the single vibronic levels decrease from 140±3 μs (0°) to 68 μs(3¹4¹5¹) with increasing excitation energies. The promoting vibrational modes for the non-radiative transition are considered to be the out-of-plane bending (ν₄) and the asymmetric rocking (ν₆) modes rather than the asymmetric stretching mode (ν₅).     

Flow pattern,void fraction and pressure drop of refrigerant two-phase flow in a horizontal pipe—II: Analysis of frictional pressure drop

Two-phase flow in horizontal pipe was analyzed with simplified models for annular and stratified flow. The velocity profiles for the liquid and gas phase were described with the Prandtl mixing length. From this analysis, the frictional pressure drop was calculated with the modified Baker map for flow pattern transition. The intermediate region, i.e. wavy flow, was interpolated between annular and stratified flow. Comparison of this analysis with existing experimental data of refrigerants showed good agreement.     

Organometallic chemistry related to applications for microelectronics in Japan

This is meant to be a brief overview of the developments of research activities in Japan on organometallic compounds related to their use in electronic and optoelectronic devices. The importance of organometallic compounds in the deposition of metal and semiconductor films for the fabrication of many electronic and opto-electronic devices cannot be exaggerated. Their scope has now extended to thin-film electronic ceramics and high-temperature oxide superconductors. A variety of organometallic compounds have been used as source materials in many types of processing procedures, such as metal–organic chemical vapor deposition (MOCVD), metalorganic vapor-phase epitaxy (MOVPE), metal–organic molecular-beam epitaxy (MOMBE), etc. Deposited materials include silicon, Group III–V and II–VI compound semiconductors, metals, superconducting oxides and other inorganic materials. Organometallic compounds are utilized as such in many electronic and optoelectronic devices; examples are conducting and semiconducting materials, photovoltaic, photochromic, electrochromic and nonlinear optical materials. This review consists of two parts: (I) research related to the fabrication of semiconductor, metal and inorganic materials; and (II) research related to the direct use of organometallic materials and basic fundamental research.     

Energy transfer between rhodamine-6G and 3,3′-diethylthiacarbocyanine iodide enhanced in the premicellar region

The energy transfer between rhodamine-6G and 3,3′-diethylthiacarbocyanine iodide was studied in aqueous solutions of sodium lauryl sulfate. A highly enhanced energy transfer was observed at very low dye concentrations in the premicellar region. This effect can be explained in terms of the formation of dye-rich mixed micelles.