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Ohne Zusammenfassung übersetzt von H. Erbring (Leipzig).  相似文献   
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Ohne Zusammenfassung Uebersetzt von F. Engel (Leipzig).  相似文献   
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This study reports on the formation of cadmium sulfide (CdS) nanostructures with controlled morphology synthesized via a simple chemical route in surface active agent environment. The effect of organic surface active agents (surfactants) as sodium dodecyl sulfate (SDS), polyethylene glycol (PEG) and cetyltrimethylammonium bromide (CTAB) on structural, morphological, optical and photoelectrochemical properties of CdS thin films have been studied. Our results reveal that the organic surfactants play key roles in tweaking the surface morphology. A compact spongy ball like morphology was observed for the CdS samples grown without organic surfactants. The cauliflower's with nanopetals from the CTAB, whereas crowded star fish like morphology is observed in PEG-mediated growth. Water hyacinth like morphology is tweaked using SDS. Considering the importance of these nanostructures, the growth mechanism has been discussed in details. Additionally, the samples are photoelectrochemically (PEC) active and having a compact surface with a nanoporous structure twig helps in improved photoelectrochemical performance compared to that of CdS deposits from surfactant free solution. This is a simplistic way to tune the morphology using surfactants, which can be applied to other energy conversion applications.  相似文献   
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The modified Jain–Khare semi-empirical formalism for the evaluation of differential and integral electron impact ionization cross sections for molecules has been extended to the evaluation of cross sections for the electron ionization of CO2 clusters: (CO2)240 and (CO2)1700. The energy dependent differential cross sections are evaluated at the incident electron energies of 50, 100 and 200 eV. The integral total ionization cross sections have been calculated in the energy range varying from ionization thresholds to 1000 eV which revealed a good agreement with the available experimental and the theoretical data. The ionization rate coefficients have also been evaluated using the presently calculated ionization cross sections and Maxwell–Boltzmann energy distributions.  相似文献   
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Tris(8-hydroxyquinoline) metal complex (AlQ3) is a widely used light-emitting material in organic light-emitting devices (OLEDs). The environmental stability is still a major problem with OLEDs and needs further improvements. In this report, we examine the optical properties of the thin films of this material and the effect of environment on it. The annealing in different ambients were done with the aim to understand the physical phenomenon involved in AlQ3 thin films. An enhanced photoluminescence intensity is observed for the samples annealed in oxygen near 100 °C. Sudden change in roughness which may be as a consequence of change in surface morphology due to phase change and fraction of new phase is estimated by phase images taken by Atomic Force Microscopy (AFM). The enhanced photoluminescence is understood in terms of formation of a new phase.  相似文献   
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The reaction of 2,3-dihydrofuran (1), dihydropyran (2) and indole (8) with acyloxysulfonium salt (3) and Methyl amine furnished vinyl sulfides 6, 7 and 10 respectively in very good yields.  相似文献   
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