X-ray emission from multi-inner-shell excited states produced by high-intensity short-pulse X-rays

We study the double inner-shell ionization produced by high-intensity short-pulse X-rays and the X-ray emission from doubly inner-shell excited states of Mg (1s ²2s ²2p ⁴3s ²) and Xe (1s ²2s ²2p ⁶3s ²3p ⁶4s ²4p ⁶4d ⁸5s ²5p ⁶). The intensity and pulse width dependence on the X-ray emission is studied.     

Gas chromatographic determination for forensic purposes of petroleum fuel inhaled just before fatal burning

The determination of petroleum fuel in the blood of burned bodies was carried out by three different gas chromatographic procedures. Seven components of gasoline (isopentane, n-pentane, 2-methylpentane, benzene, 2-methylhexane, 3-methylhexane and toluene) and five of kerosene (xylene, C9H20, mesitylene, pseudocumene and C11H24) were chosen as indicators with a coefficient of variation of 5-24%. The methods were applied to four autopsy cases with a relatively low carboxyhaemoglobin (HbCO) content. When gasoline exposure had occurred, the blood concentrations determined were almost identical whatever the components selected. Great variations in the components determined were found after kerosene exposure, and hydrocarbons greater than or equal to C14 were hardly inhaled by the victims. A higher content of fuel in the left than in the right ventricular blood observed in the autopsy cases suggests fuel inhalation just before death. The same phenomenon was also observed in the content of blood HbCO. Determinations of petroleum fuel and HbCO in both the right and left ventricular blood would be useful for the forensic diagnosis on burned bodies with a low HbCO content.     

Photovoltaic performance of dye-sensitized solar cells based on donor-acceptor pi-conjugated benzofuro[2,3-c]oxazolo[4,5-a]carbazole-type fluorescent dyes with a carboxyl group at different positions of the chromophore skeleton

Donor-acceptor pi-conjugated benzofuro[2,3-c]oxazolo[4,5-a]carbazole-type fluorescent dyes 3a, 3b, 8a, and 8b with a carboxyl group at different positions of the chromophore skeleton have been designed and synthesized. The absorption and fluorescence spectra and cyclic voltammograms of the fluorescent dyes agree very well, showing that the position of the carboxyl group has a negligible influence on the photophysical and electrochemical properties of these dyes. When these dyes are used in dye-sensitized solar cells, however, their photovolatic performances are considerably different. The short-circuit photocurrents and energy conversion efficiencies under a simulated solar light increase in the order: 3a (2.12 mA cm(-2), 1.00%) approximately 3b (2.10 mA cm(-2), 1.06%) > 8b (1.50 mA cm(-2), 0.67%) > 8a (0.84 mA cm(-2), 0.34%). Based on semi-empirical molecular orbital calculations (AM1 and INDO/S) together with spectral analyses and their photovolatic performance, the relationships between the observed photovolatic properties and the chemical structures of the benzofuro[2,3-c]oxazolo[4,5-a]carbazole-type fluorescent dyes are discussed. It is found that strong interaction between a TiO(2) surface and the electron accepting moiety of the dye leads to a high photovoltaic performance.     

Safety improvement of lithium ion batteries by organo-fluorine compounds

Thermal stability, electrochemical oxidation stability and charge/discharge characteristics of natural graphite powder were investigated by mixing of five fluoro-carbonates with 1 mol/L LiClO₄–EC/DEC/PC (1:1:1 vol.). DSC study revealed that thermal stability of the electrolyte solution was improved by mixing of fluoro-carbonates by 10.0–33.3 vol.%. Electrochemical oxidation stability was also improved. Oxidation currents for Pt electrode significantly decreased by mixing of fluoro-carbonates. In the fluoro-carbonate-mixed electrolyte solutions, electrochemical reduction of PC decreased with increasing concentration of fluoro-carbonate and current density. As a result, first coulombic efficiency for natural graphite electrode increased, that is, irreversible capacity decreased in the fluoro-carbonate-mixed solutions.     

Total synthesis of (+)-mycalamide A

A convergent total synthesis of (+)-mycalamide A is described. A Yb(OTf)3-TMSCl catalytic system is used to synthesize a trioxadecalin ring system, which contains the right segment of mycalamide A. In addition, a tetrahydropyran ring, which is the left segment, is constructed with use of a novel one-pot delta-lactonization protocol. Both segments are prepared from a common starting material, d-mannitol. These segments are then coupled and the functional groups are transformed to synthesize (+)-mycalamide A.     

ChemInform Abstract: On Compound Formation of M′O:M2O3. Part 11. Crystal Structure of BaIn2O4.

Single crystals of the title compound, obtained from a melt after reacting intimate mixtures of BaCO₃ and In₂O₃ at 840 °C (12 h), belong to the monoclinic space group P2₁/a with Z=16.     

ChemInform Abstract: Boron Occupied Condensed Clusters in Ta5Ge3By (y ≈ 0.7).

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