A theoretical study on the ionization of OCS with an analysis of vibrational structures of the photoelectron spectrum

 Ab initio calculations have been performed to study the molecular structures and vibrational levels of the four low-lying ionic states (1, 2²Π, and 1, 2²Σ⁺) of carbonyl sulfide. The global regions of the potential-energy surfaces have been obtained by multireference single and double excitation configuration interaction calculations. Vibrational calculations using explicit vibrational Hamiltonians have been used for vibrational analysis. The equilibrium molecular structures and a vibrational analysis of the four ionic states are presented. The theoretical ionization intensity curves including the vibrational structures of the ionic states are also presented and are compared with the photoelectron spectrum. Received: 20 January 2001 / Accepted: 22 August 2001 / Published online: 30 October 2001     

Design and Synthesis of 6 α-Corticosteroid Haptens and Their Bovine Serum Albumin(BSA) Conjugates

The site of attachment of protein carrier to corticosteroids has great influence on the specificity of produced antibody.In order to obtain highly specific and accurate antibodies for bioimmunoassay determination of cortisol,different tether lengths of 60633－corticosteroid haptens and their BSA conjugates were designed and synthesized.     

Temperature and matrix effects on competitive intermolecular and intramolecular reaction of benzylchlorocarbenes in ethanol

Benzylchlorocarbenes generated photolytically from diazirines in EtOH afford chlorostyrenes and acetals, whose distributions are sensitive to the reaction temperature.     

Bis(triethoxysilyl)ethane (BTESE)-derived silica membranes: pore formation mechanism and gas permeation properties

Based on their high performance in gas and liquid-phase separations, 1,2-bis(triethoxysilyl)ethane (BTESE)-derived organosilica membranes have attracted much attention. To improve performance, we focused on the acid molar ratio (AR) in sol preparation and its effect on the pore formation mechanism during sol-gel processing. BTESE-derived sols with AR?=?10^?4–10⁰ were prepared, and the effect of the AR on the gel structure was evaluated in detail via FT-IR, nuclear magnetic resonance (NMR), N₂ adsorption, and positron annihilation lifetime (PAL) measurements. The chemical structure of the gels was confirmed by FT-IR and NMR and showed that sols with the largest number of silanol groups (AR?=?10^?2) experienced a significant increase in condensation during the firing process. The porous structures of fired gels characterized by N₂ adsorption and PAL measurement showed that the AR?=?10^?2 fired gel consisted of a larger number of small pores that had formed during the firing process. Single-gas permeation experiments showed high H₂ permeance (5–9?×?10^?7?mol/(m²?Pa?s)) and H₂/CF₄ selectivity (700–20,000). The gas permselectivity (He/H₂, H₂/N₂, and H₂/CF₄) was highest for the intermediate AR (=10^?2), which corresponded to the greatest amount of silanol groups in unfired gels and confirmed that small pores had formed from the condensation of silanol groups during firing.

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Photocatalytic degradation of hexachlorocyclohexane (HCH) by TiO2-pillared fluorine mica

A significant effect of clay host was observed on the photocatalytic activity of TiO2; TiO2-pillared fluorine mica exhibited two orders of magnitude higher activity than TiO2 and TiO2-pillared montmorillonite for the photocatalytic degradation of gamma-HCH.