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It is shown that the long-lived transient absorption which is observed when solutions of cryptocyanine and DDI (1, 1′-diethyl-2, 2′-dicarbocyanine iodide) in methanol and other alcohols are exposed to nanosecond ruby laser pulses arises from a photoproduct whose formation requires consecutive absorption of two photons. 相似文献
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Baranwal Alok Kumar Sharma Shashibhushan Roy Sanjay Dhar Kundu Sumit 《Wireless Personal Communications》2022,124(2):1281-1296
Wireless Personal Communications - This paper proposes and analyses the power allocation coefficient normalization for successive interference cancellation in power-domain non-orthogonal multiple... 相似文献
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The structure of the abnormal product 1a formed in the Knoevenagel condensation of 2-carbethoxycyclohexanone and malononitrile has been further confirmed. Oxidation of the tetrahydroisoquinoline 3b using Na2Cr2O-AcOH-H2SO4 gave the keto isoquinoline 3d and the isoquinoline-1-carboxylic acid 5a. The acid chloride of 5a was condensed with diethyl ethoxymagnesiomalonate to afford after decarbethoxylation the methyl ketone 5d which on Baeyer-Villiger oxidation gave a mixture of the acetate 1g and the title compound 1b. The unambiguous synthesis of 1b confirms the structure assigned earlier to the title compound also formed during the partial hydrolysis of the diethoxy compound 1c. Condensation of 2-acetylcyclohexane-1,3-dione with malononitrile gave the quinoline derivative 4c which on ethylation yielded the ketoquinoline 4d. The present studies have confirmed that the quinoline compound 4a is also formed in the condensation of 2-acetylcyclohexanone and cyanoacetamide. 相似文献
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1. Contrary to the observations of earlier workers, it has been shown that formic acid can be quantitatively oxidixed by ceric sulphate in the presence of concentrated sulphuric acid. 2. Tartaric, malonic, malic and glycolic acids can also be oxidized completely to carbon dioxide and water by the following general procedure : to a known amount of the organic acid is added ceric sulphate (excess) solution in dilute sulphuric acid and the mixed solution refluxed for ten to fifteen minutes. Concentrated sulphuric acid (double the volume of the reaction mixture) is then added taking care that formic acid is not lost during the addition, and the mixture again refluxed for 45 to 50 minutes. The excess ceric sulphate is determined by titrating against ferrous ammonium sulphate. 3. The complete oxidation of the above acids provides satisfactory methods for their quantitative estimation. 相似文献
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n-Propyl tin trichloride and its complexes with bases as pyridine, α, β-and γ-picolines, isoquinoline, piperidine, morpholine, aniline and benzylamine have been prepared. The complexes have been characterised by their I.R. and molar conductance measurements. Assignments for some I.R. frequencies have been reported and discussed. Molar conductance values of some of the complexes in nitrobenzene categories them to be uni-univalent electrolytes. 相似文献
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Abstract— The relationship between energy metabolism and UV-induced (251 nm) DNA repair has been investigated in leukocytes obtained from peripheral blood of chronic myeloid leukaemia patients. Energy supply was modulated by using inhibitors of respiratory (antimvcin-A) and glycolytic (2-deoxy-o-glucose and other glucose analogues) pathways for adenosine-triphosphatc (ATP) production. DNA repair was measured by the unscheduled DNA synthesis technique. Parameters of energy metabolism like glucose utilization. lactate production and ATP content of cells. were measured under similar experimental conditions. The observations made indicate the following results: (1) ATP for DNA repair can be supplied by the respiratory and/or by the glycolytic pathway. (2) In the absence of respiration, the rate of glycolysis bears a linear correlation with DNA repair. (3) A minimum threshold rate of ATP-production is necessary for DNA repair. 相似文献
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Raman spectra of NaNO2 have been studied as a function of hydrostatic pressure to 40 kbar at 295 and 348 K. Slight changes in slope of mode frequency versus pressure plots support the view that a structural anomaly exists at 9 ± 1 kbar. The absence of qualitative changes in the Raman spectra allow the space group of NaNO2 IV to be specified as one of P1, P2, B2, Pm or Bm. The Raman spectrum of NaNO3 has been studied to 87 kbar. The changes observed are fully consistent with a second-order transition to a phase with symmetry C63v, as indicated by previous X-ray work, although the transition is sluggish. 相似文献