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Supported nano-gold catalysts have attracted rapidly growing interest due to their potential applicability to various reactions of industrial and environmental significance. In this article, we focus on the advances related to the direct vapor-phase oxidation of propene to propene oxide in the presence of molecular oxygen and hydrogen over gold catalysts supported on Ti-incorporated silica materials prepared by different methods. The importance of catalyst preparation and pretreatment method, nature of support material, Au particle size and loading amount is emphasized. Possibilities to enhance the catalyst performance by using promoters and by silylation are also discussed. [ABSTRACT FROM AUTHOR]

Purpose. Nitric oxide, a messenger molecule has been reported as having various antineoplastic properties. The activation of insulin-activated nitric oxide synthase (IANOS) was found to be related to the production of NO as a result of the binding of insulin to its receptor through the activation of tyrosine kinase in erythrocyte membrane. As nitric oxide is reported to be a systemic anticancer agent, studies were carried out to determine the role of insulin receptor binding that lead to the activation of tyrosine kinase and IANOS in erythrocytes in breast cancer. Methods. Blood samples were collected from female breast cancer patients who, at the time of participation in the study, had not undergone any therapeutic intervention but had opted for surgery. The binding of insulin to its receptor in erythrocyte membrane and the activation of both receptor tyrosine kinase and IANOS due to the hormone binding were determined and compared with the appropriate control. Results. It was found that the impaired NO synthesis in erythrocyte membrane in breast cancer was related to the marked decrease of insulin binding sites of the high-affinity hormone receptor population. This impaired insulin binding to high-affinity receptors resulted in the impairment of both reaction velocity (Vmax) of the IANOS and receptor tyrosine kinase activation. Conclusion. These results indicated that the impairment of interaction between insulin and its high-affinity receptors in erythrocyte membrane might be a critical pathophysiological event in the development of breast cancer. [ABSTRACT FROM AUTHOR]

Recoil mass spectrometers (RMS) are ideal instruments for identifying weakly populated reaction products in the forward angle from heavy-ion reactions amidst an intense beam background. The Heavy Ion Reaction Analyzer (HIRA) at the Nuclear Science Centre (NSC), New Delhi, is one of the few operating first generation RMSs. The features of and physics studies pursued using HIRA are covered in the paper. With the augmentation of the accelerator facilities at NSC, a second generation RMS combined with a gas-filled separator is planned. The design details of the new facility, Hybrid Recoil Mass Analyzer (HYRA), are presented. HYRA will be operated either stand-alone or in conjunction with a Large Gamma Array (LGA) at its target position. Physics studies planned with these forthcoming facilities are outlined.© 2003 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

Ti-MCM-41 samples were used for propene epoxidation using H2 and O2 after Au deposition by deposition--precipitation. Au nanoparticles supported on Ti-MCM-41 with Ti incorporated hydrothermally followed by post-synthesis grafting gave higher propene oxide yields than Ti-MCM-41 with Ti incorporated hydrothermally or by grafting. Au L3-edge EXAFS spectra show the presence of metallic Au for the low Au content (0.21 wt%) catalyst which is more selective to epoxidation, while at high Au loadings (0.42 wt%) oxidic Au species are observed and the catalyst shows lower epoxide selectivity. [ABSTRACT FROM AUTHOR]

High spin states in70Ge nucleus have been studied in two different experiments using heavy ion fusion evaporation reaction. The Gamma Detector Array comprising of eight Compton-suppressed High Purity Ge detectors, was used in conjunction with a Recoil Mass Spectrometer - the HIRA - in order to identify and measure the transitions of this weakly populated nucleus. The level scheme is extended up to an excitation energy of13MeV for spin-parity 21- with several newly observed transitions placed in it. A rotational like band is also observed in this nucleus for the first time. [ABSTRACT FROM AUTHOR]

MnAPO 11 samples were synthesized from aqueous (MnAPO 11(A)) and ethylene glycol (MnAPO 11(NA)) media. The crystallinity of the samples was more when the synthesis was carried out in ethylene glycol. Chemical and thermogravimetric analyses reveal greater incorporation of Mn in the framework of MnAPO 11(NA) than in MnAPO 11(A). At least five different types of Mn(II) species are detected in the samples by ESR. The studies suggest that Mn is more homogeneously distributed in MnAPO 11(NA) than in MnAPO 11(A). [ABSTRACT FROM AUTHOR]

Measurements were carried out to deduce the transverse kinetic energies of highly charged argon recoil ions produced in single collisions of 120 MeV ions with argon atoms in which the post collision charge states of the projectiles were not determined. A time of flight spectrometer was designed and fabricated to detect the charge states of recoils. Experimental procedures for optimizing the spectrometer for extraction, transmission and detection of recoils are described. A simple approach for determining the transverse kinetic energy of the recoil ions from FWHM of the peaks is reported. This method is shown to be independent of the choice of collision partners and requires only the knowledge of the physical values of “optimized parameters” of time-of-flight spectrometer used in the experiment. The transverse kinetic energy of the recoil ions determined from the present approach is found to vary from 0.03 eV for to 4.02 eV for Ar10+. These values are compared with the results reported by earlier workers and are shown to follow a q2-behaviour up to a charge state q =8+ of the recoil ions. [ABSTRACT FROM AUTHOR]