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S. Padmaja V. Ramakrishnan J. Rajaram J. C. Kuriacose 《Journal of Chemical Sciences》1988,100(4):297-303
The borate radical is produced by the flash photolysis of an aqueous alkaline solution of NaBO2 and K2S2O8. The absorption spectrum of the transient borate radical shows two maxima. The self decay of this radical is second order.
Rate constants for the reactions of this radical with some organic substrates have been determined. 相似文献
16.
Reaction of β-naphthyl cinnamate with anhydrous aluminum chloride afforded 9-hydroxyphenalenone5 by a Fries rearrangement followed bya dearylative cyclisation. 9-Hydroxy-3-phenyl-2,3-dihydrophenaIen-l-one7 was identified as an intermediate. 相似文献
17.
T. P. Elango V. Ramakrishnan S. Vancheesan J. C. Kuriacose 《Journal of Chemical Sciences》1984,93(1):47-52
Rate constants for the reaction of carbonate radical with aniline and some parasubstituted anilines have been determined by
the flash photolysis technique. Using σ+ para values the rate constants at pH 8.5 correlate very well with the Hammett equation yielding ρ= − 1. The carbonate radical oxidises aniline giving the anilino radical. The products so formed have been identified through
studies under conditions of continuous irradiation. 相似文献
18.
L. Ramakrishnan Prof. Dr. S. Soundararajan 《Monatshefte für Chemie / Chemical Monthly》1977,108(1):225-231
Complexes of 2,6-dimethylpyridine 1-oxide with lanthanide iodides of the formulaeLn(2,6-LTNO)5I3 whereLn=La, Tb and Yb,Ln(2,6-LTNO)4I3 whereLn=Pr and Nd and Er(2,6-LTNO)4.5I3 have been prepared and characterised by chemical analysis, infrared and conductance studies. Infrared and conductance data have been interpreted in terms of dimeric (or polymeric) structures involving bridging amine oxide groups.
Mit 2 Abbildungen 相似文献
Mit 2 Abbildungen 相似文献
19.
Narayani Ramakrishnan Nancy L. Oleinick Marian E. Clay Min-Fen Horng Antonio R. Antunez Helen H. Evans 《Photochemistry and photobiology》1989,50(3):373-378
Two closely related strains of mouse lymphoma L5178Y cells, LY-R and LY-S, have been found to differ in their sensitivity to the cytotoxic effects of photodynamic treatment (PDT) with chloroaluminum phthalocyanine (CAPC) and red light. Strain LY-R is more sensitive to photodynamic cell killing than strain LY-S. Differences in uptake of CAPC could not account for the differences in cytotoxic effects. There was no marked difference between the two strains in the induction of single-strand breaks (which includes frank single-strand breaks and alkali-labile lesions), but substantially more DNA-protein cross-links were formed in strain LY-R by CAPC and light. Repair of single-strand breaks proceeded with similar kinetics in both strains for the first 30 min post-irradiation, suggesting that these lesions are not responsible for the differential sensitivity of the two strains to the lethal effects of photodynamic treatment. Thereafter, alkaline elution revealed the presence of increasing DNA strand breakage in strain LY-R. DNA degradation, as measured by the conversion of prelabeled [14C] DNA to acid-soluble radioactivity, was more rapid and extensive in strain LY-R. 相似文献
20.
T. P. Elango S. Vancheesan V. Ramakrishnan J. C. Kuriacose 《Journal of Radioanalytical and Nuclear Chemistry》1988,125(1):151-155
Carbonate radical shows moderate reactivity (k2=1.8·106 M–1 s–1) with nickelglycine complex. As an oxidizing free radical, it may attack the ligand to form Ni(II) coordinated glycine radical or oxidize the metal center to form a Ni(III) glycine transient. Continuous -irradiation of the complex-bicarbonate mixture yields glyoxalic acid (G=1.7) as the major product. The reaction involves an attack of the ligand and precludes the oxidation of metal center. 相似文献