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651.
Dipti Prakasini Das Kulamani Parida Bhudev Ranjan De 《Journal of molecular catalysis. A, Chemical》2005,240(1-2):1-6
The photodegradation of phenol was studied in the aqueous solutions over titania pillared zirconium phosphate and titanium phosphate under solar radiation and compared with that of the UV-radiation (6 W low pressure Hg vapor lamp). This reaction was studied by varying different parameters such as catalyst dose, initial phenol concentration, pH of solution and irradiation time. The degradation rate of phenol was favourable under neutral pH condition. The degradation process approximately obeyed first-order kinetics with apparent rate of degradation constant increasing with decreasing the initial phenol concentration. 相似文献
652.
Abe F Amidei D Apollinari G Atac M Auchincloss P Baden AR Bamberger A Barbaro-Galtieri A Barnes VE Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Bensinger J Beretvas A Berge JP Bertolucci S Bhadra S Binkley M Blair R Blocker C Booth AW Brandenburg G Brown D Buckley E Byon A Byrum KL Campagnari C Campbell M Carey R Carithers W Carlsmith D Carroll JT Cashmore R Cervelli F Chadwick K Chiarelli G Chinowsky W Cihangir S Clark AG Connor D Contreras M Cooper J Cordelli M Crane D Curatolo M 《Physical review letters》1990,64(2):152-156
653.
Ranjan Prasad Srivastava Neelima Amiya Prasad Bhaduri 《Journal of heterocyclic chemistry》1987,24(1):219-222
New examples of synthetic applications of 2-chloro-3-formylquinoline, as evident from the novel and facile syntheses of 3-aminoisooxazolo[5,4-b]quinoline (4), 3-hydroxyfuro[2,3-d]theino[2,3-b]quinoline-2-carboxamide (7) and 3-hydroxymethyl-2-(3-formyl)phenylquinoline ( 13 ), have been furnished. 相似文献
654.
Ranjan Bhowmik R. R. Doering Aaron Galonsky P. S. Miller 《Zeitschrift für Physik A Hadrons and Nuclei》1977,280(3):267-269
The proton decays \(\tilde p\) of isobaric analog states of207, 208Pb in the reactions207, 208Pb(p, n) have been studied using a neutron-proton coincidence technique. The width anomaly observed in (p, n) [4] and (p, n \(\tilde p\) ) singles spectra [11] is resolved in the coincident spectra. 相似文献
655.
A simple and sensitive spectrophotometric method for the determination of vanadium based upon the reaction of vanadate with 1,10-phenanthroline in the presence of sodium dithionite in ammoniacal solution is described. The absorbance of the complex measured at 645 nm follows Beer's law for solutions containing 30-400 microg of vanadium in 100 ml of solution. A 10-fold excess of molybdenum, tungsten, phosphorus or chromium does not interfere. The molar absorptivity is 8.0 x 10(3) 1 mole(-1) cm(-1). The complex is shown to be tris-1,10-phenanthroline vanadium(II). The method has been applied successfully to the determination of vanadium in bauxite. 相似文献
656.
Daniel E. Diaz David A. Quist Austin E. Herzog Andrew W. Schaefer Ioannis Kipouros Mayukh Bhadra Edward I. Solomon Kenneth D. Karlin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(49):17736-17740
The dioxygen reactivity of a series of TMPA‐based copper(I) complexes (TMPA=tris(2‐pyridylmethyl)amine), with and without secondary‐coordination‐sphere hydrogen‐bonding moieties, was studied at ?135 °C in 2‐methyltetrahydrofuran (MeTHF). Kinetic stabilization of the H‐bonded [( TMPA)CuII(O2.?)]+ cupric superoxide species was achieved, and they were characterized by resonance Raman (rR) spectroscopy. The structures and physical properties of [( TMPA)CuII(N3?)]+ azido analogues were compared, and the O2.? reactivity of ligand–CuI complexes when an H‐bonding moiety is replaced by a methyl group was contrasted. A drastic enhancement in the reactivity of the cupric superoxide towards phenolic substrates as well as oxidation of substrates possessing moderate C?H bond‐dissociation energies is observed, correlating with the number and strength of the H‐bonding groups. 相似文献
657.
Pentafluorophenylantimony(V) di- and tetracarboxylates of the molecular formula C6F5SbX2L2 (when X=L=OCOR (R=CH3, CH2Cl, CHCl2, CCl3, CF3, CH2OC6H3Cl2-2,4, CH2OC6H2Cl3-2,4,5) and when X=Cl; L=OCOCH3, OCOCHCl2) have been synthesized by the metathetical reaction of pentafluorophenylantimony(V) tetrachloride and (dibromide)dichloride with corresponding sodium salt of carboxylic acids in appropriate molar ratio using 15-crown-5 as phase transfer catalyst. The van’t Hoff factor ‘i’ and molar conductance data of the compounds revealed them to be monomeric and non-conducting in nature. Elemental analysis, UV, IR and NMR (1H, 19F and 13C) were used to characterize the derivatives. Compounds are tentatively assigned as a pentacoordinated square pyramidal structure in which carboxylate ligand behaving as a monodentate ligand. 相似文献
658.
A polysoap poly(sodium 11-acrylamidoundecanoate) was synthesized from sodium 11-acrylamidoundecanoate in water. The molecular weight of the polymer was determined by gel permeation chromatography and static light scattering techniques. Fluorescence probe studies in water have suggested the formation of hydrophobic domains within the same polymer chain. The microenvironment of the hydrophobic domains is highly ordered. The packing of the hydrocarbon chains in the hydrophobic domains formed by intra-chain association increases upon decrease of pH. The transmission electron micrograph revealed large vesicular aggregates in dilute aqueous solution. Temperature-dependent fluorescence anisotropy of the 1,6-diphenyl-1,3,5-hexatriene probe demonstrated stability of the vesicles. 相似文献
659.
Abe F Amidei D Anway-Wiese C Apollinari G Atac M Auchincloss P Azzi P Baden AR Bacchetta N Badgett W Bailey MW Bamberger A de Barbaro P Barbaro-Galtieri A Barnes VE Barnett BA Bauer G Baumann T Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Benjamin D Benlloch J Bensinger J Beretvas A Berge JP Bertolucci S Biery K Bhadra S Binkley M Bisello D Blair R Blocker C Bodek A Bolognesi V Booth AW Boswell C Brandenburg G Brown D Buckley-Geer E Budd HS Busetto G Byon-Wagner A Byrum KL 《Physical review letters》1992,69(24):3439-3443
660.
Abe F Amidei D Anway-Wiese C Apollinari G Atac M Auchincloss P Azzi P Baden AR Bacchetta N Badgett W Bailey MW Bamberger A de Barbaro P Barbaro-Galtieri A Barnes VE Barnett BA Bauer G Baumann T Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Benjamin D Benlloch J Bensinger J Beretvas A Berge JP Bertolucci S Biery K Bhadra S Binkley M Bisello D Blair R Blocker C Bodek A Bolognesi V Booth AW Boswell C Brandenburg G Brown D Buckley-Geer E Budd HS Busetto G Byon-Wagner A Byrum KL 《Physical review letters》1992,69(26):3704-3708