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221.
Nath S Ghosh SK Panigrahi S Pal T 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(9):2145-2151
In this report, selenious acid (H2SeO3) has been exploited to study the decolorization of a cationic dye, dimethylmethylene blue (DMMB) with UV-light. Micelles have effectively been employed as organized media to promote the rate of decolorization of the dye molecules. Micellar catalysis has been explained as a consequence of electrostatic, hydrophobic and charge transfer interactions. It has also been shown that strong charge transfer and electrostatic interaction lead to an appreciable enhancement of the reaction rate in micelle, whereas, weak hydrophobic interaction is of marginal importance. Existence of monomer-dimer equilibrium for the dye molecules under certain selective environments has been identified spectrophotometrically. Then the shift of dimer-monomer equilibrium of the dye has been successfully studied in aqueous and micellar environments exploiting photodecolorization process for the dye in solution. 'Salting-in' and 'salting-out' agents were introduced into the reaction mixture to examine the viability of the dye decolorization process for dye contaminated water samples. 相似文献
222.
Rabinder Nath 《Journal of Molecular Structure》1983,102(3-4):355-363
A series of stable beryllium(II) complexes of newly synthesized N-aralkylsalicylaldimine Schiff bases has been prepared and characterized. Structures have been elucidated on the basis of analytical, conductance and IR and PMR spectral data. A tetrahedral symmetry has been proposed for all these complexes which are non-ionic. 相似文献
223.
Mool C. Gupta Jaya D. Nath 《Journal of polymer science. Part A, Polymer chemistry》1980,18(2):709-712
The entropy of fusion of linear vinyl polymers [polypropylene, polystyrene, and poly(vinyl chloride)] having asymmetric carbon atoms was calculated on the basis of the rotational isomeric state model. The results are found to be in good agreement with the experimental entropies of fusion per bond for these polymers. 相似文献
224.
Experiments are performed to develop a pulsed corona discharge system for the conversion ofmethane to hydrogen at atmospheric pressure (≌760 Torr) without using a catalyst. The corona dischargewas energized by 10-12 μs wide voltage pulses (≤7 kV) at a repetition rate of about 1.0-1.5 kHz. Theresidual gases were characterized by mass spectrometry. The conversion of methane is as high as 50.8% producing the 70% yield of hydrogen. The influences of argon on the discharge of methane were studied.This result could be useful for the mass production of hydrogen in both academic and industrial point ofview. 相似文献
225.
226.
Somnath Roy Tarak Nath Mandal Anil Kumar Barik Sachindranath Pal Samik Gupta Arijit Hazra Ray J. Butcher Allen D. Hunter Matthias Zeller Susanta Kumar Kar 《Polyhedron》2007
Two new pyrimidine based NNS tridentate Schiff base ligands S-methyl-3-((2-S-methyl-6-methyl-4-pyrimidyl)methyl)dithiocarbazate [HL1] and S-benzyl-3-((2-S-methyl-6-methyl-4-pyrimidyl)methyl)dithiocarbazate [HL2] have been synthesised by the 1:1 condensation of 2-S-methylmercapto-6-methylpyrimidine-4-carbaldehyde and S-methyl/S-benzyl dithiocarbazate. A Ni(II) complex of HL1 and Co(III) and Fe(III) complexes of HL2 have been prepared and characterized by elemental analyses, molar conductivities, magnetic susceptibilities and spectroscopic studies. All the bis-chelate complexes have a distorted octahedral arrangement with an N4S2 chromophore around the central metal ion. Each ligand molecule binds the metal ion using the pyrimidyl and azomethine nitrogen and thiolato sulfur atoms (except in the nickel complex, one ligand molecule uses the thione sulfur in lieu of thiolato sulfur atom). In the Ni(II) complex, one of the ligand molecules behaves as a neutral tridentate and the other molecule functions as a uninegative tridentate, whereas in the Co(III) and Fe(III) complexes, the ligand molecules behave as monoanionic tridentate. All the complexes were analyzed by single crystal X-ray diffraction and significant differences concerning the distortion from an octahedral geometry of the coordination environment were observed. 相似文献
227.
Summary A systematic scheme for the identification of the common anions: sulphate, sulphite, nitrate, nitrite, fluoride, chloride, bromide, iodide, ferricyanide, ferrocyanide, thiocyanate, phosphate, sulphide, thiosulphate and borate in a mixture by the ring oven technique has been described.
Zusammenfassung Ein systematischer Analysengang zum Nachweis folgender Anionen mit Hilfe des Ringofens wurde beschrieben: Sulfat, Sulfit, Nitrat, Nitrit, Fluorid, Chlorid, Bromid, Jodid, Cyanoferrat(III), Cyanoferrat (II), Rhodanid, Phosphat, Sulfid, Thiosulfat und Borat.
Résumé On a décrit un plan d'identification systématique des anions usuels dans leurs mélanges: sulfate, sulfite, nitrate, nitrite, fluorure, chlorure, bromure, iodure, ferricyanure, ferrocyanure, thiocyanate, phosphate, sulfure, thiosulfate et borate, au moyen de la technique du four annulaire.相似文献
228.
Microchimica Acta - Pregl's method for the micro-analytical determination of carbon and hydrogen of an organic substance did not give satisfactory results in the humid atmosphere of summer in... 相似文献
229.
Summary A method has been recommended for the determination of thorium and molybdenum when present in micro-quantities, based on the formation of a red coloured water soluble chelate (
max=520 nm for thorium and
max=470 nm for molybdenum) of the composition MRe=12, with sodium-alizarin-3-sulphonate. A large number of ions, however, interfere and should be removed before measurements are made. The solution of thorium chloride or ammonium molybdate may then be treated with a freshly prepared solution of Alizarin Red S. The pH should be kept within the range 3.2 to 8.0 for thorium, 3.5 to 5.6 (preferably at 5.0) for molybdenum and the colour intensity may be measured with a photoelectric colorimeter or with a spectrophotometer. Temperature has no influence on the colour intensity. Determinations are possible between 0.23 and 16.70 ppm of thorium and 0.19 to 6.9 ppm of molybdenum.
Part. II: Sinha, S. N., and A. K. Dey: Z. analyt. Chem. 183, 182 (1963). 相似文献
Zusammenfassung Zur Bestimmung von Mikromengen Thorium und Molybdän wird ein Verfahren vorgeschlagen, das auf der Bildung einer rotgefärbten, wasserlöslichen Komplexverbindung mit Natriumalizarin-3-sulfonat beruht. Die Zusammensetzung des Komplexes beträgt in beiden Fällen MeReagens=12. Die Absorptionsmaxima liegen bei 520 nm (Th) bzw. bei 470 nm (Mo). Viele Fremdionen verursachen Störungen und müssen vor der Messung entfernt werden. Die Lösung von Thoriumchlorid bzw. Ammoniummolybdat werden mit frisch bereiteter Alizarinrot S-Lösung behandelt; der pH-Wert soll im Bereich 3,2–8,0 für Thorium bzw. 3,5–5,6 (am besten 5,0) für Molybdän liegen. Die Farbintensität wird mit einem photoelektrischen Colorimeter oder einem Spektrophotometer gemessen; sie wird von der Temperatur nicht beeinflußt. Die Bestimmung läßt sich im Bereich 0,23–16,70 ppm Thorium bzw. 0,19–6,9 ppm Molybdän durchführen.
Part. II: Sinha, S. N., and A. K. Dey: Z. analyt. Chem. 183, 182 (1963). 相似文献