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901.
In this work, we have investigated the thermal radiation power spectra of 1D photonic crystal structure containing Si and SiO2 having an absorbing substrate with truncated thickness. The thermal radiation power spectra are determined by the means of a theoretical model based on a transfer matrix for both normal and oblique incidence together with Kirchhoff’s second law. It is observed that thermal radiation power spectra show strong dependence on truncation parameter and incident angle.  相似文献   
902.
903.
Polysiloxane-encapsulated "Pd"-nanoclusters were generated by reduction of Pd(OAc)(2) with polymethylhydrosiloxane, which functions as a reducing agent as well as a capping material for production and stabilization of catalytically active "Pd"-nanoparticles. Chemoselective hydrogenation of functional conjugated alkenes was achieved by in-situ- or ex-situ-generated polysiloxane-stabilized "Pd"-nanoclusters under mild reaction conditions in high yields. Electron microscopy, UV-vis, and NMR studies of the reaction mixture during the catalytic transformation were performed and, in conjunction with catalyst poisoning experiments, demonstrated unequivocally the role of polysiloxane-encapsulated "Pd"-nanoclusters as the real catalytic species. The recyclability of the "Pd"-nanoclusters was established by reusing the solid left after the reaction.  相似文献   
904.
An efficient synthesis of cis-3-(arylamino)-5-bromo-2-phenyl-2,3-dihydro-2λ5-benzo[d][1,2]-oxaphosphol-2-oxides 4a–h is described involving a three-component reaction of dichlorophenylphosphine (2), 5-bromosalicylaldehyde (1), and different substituted aromatic primary amines (3) in anhydrous benzene. The product structures were characterized by IR and NMR spectral data.  相似文献   
905.
Journal of Solid State Electrochemistry - The existing high market potential for supercapacitors in electric vehicles created enthusiasm for the development of safer and high-performance...  相似文献   
906.
Cu2O nanoparticles supported on hydrogen trititanate nanotubes (Cu2O/HTNT) catalysts have been efficiently catalyzed the multicomponent synthesis of 1,2,3‐triazoles in water at room temperature from different azide precursors, for example organic halides, sulfonates and anilines. The catalysts were synthesized by hydrothermal & wet‐impregnation methods and was characterized by HR‐TEM, EDS, XRD, XPS, N2‐adsorption desorption and ICP‐MS analysis. The catalyst could be recycled by centrifugation and reused up to seven cycles. The 1‐benzyl‐4‐(4‐chlorophenyl)‐1H‐1,2,3‐triazole ( 25 ) structure was proven by single crystal X‐ray diffraction studies.  相似文献   
907.
New derivatives of tetrakis(4-carboxyphenyl) porphyrin were designed, synthesized and characterized by IR, proton NMR and mass spectroscopy. The ground and excited state nature of new derivatives were examined using UV-Vis. absorption and fluorescence spectroscopy, fluorescence quantum yield and fluorescence lifetime studies. The singlet oxygen quantum yield of each synthesized derivative of porphyrin was estimated for their further efficacy as potential photosensitizer in biological studies. The significant photophysical data of all synthesized derivatives was supplementary accessed to examine the cell imaging and cytotoxicity against two cancer cell lines viz. MBA-MD-231 and A375. The fluorescence lifetime, fluorescence quantum yield and efficiency of singlet oxygen generation suggests alkyl amine and alkyl hydrazide linked new porphyrin photosensitizers can be useful for PDT agent in cancer treatment.  相似文献   
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