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21.
The use of 1,2-naphthoquinone-2-semicarbazone-4-sulphonic acid and 1,2-naphtho-quinone-2-thiosemicarbazone-4-sulphoic acid as indicators in the titrimetric estimation of phosphate, molybdate, tungstate and sulphate with lead has been examined. The precision, accuracy and applicability of the methods have been evaluated. 相似文献
22.
Suresh C. Shrivastawa Vikash C. Garg Arun K. Dey 《Fresenius' Journal of Analytical Chemistry》1969,248(5-6):305-306
Summary Eriochromecyanine RC has been used as chromogenic reagent for the photometric determination of rhodium(III) on a micro scale. A coloured Rh(III)-ECRC chelate with
max 530 nm at pH 4.0 (25°C) is formed. A detailed study has been made concerning to characteristics, composition and stability of the chelate. Standard deviation was ±1.17%.
Über die photometrische Bestimmung von dreiwertigem Rhodium mit Eriochromcyanin RC
Zusammenfassung Ergebnisse einer Untersuchung über die Zusammensetzung und Stabilität des Komplexes werden mitgeteilt. Das Absorptionsmaximum liegt bei 530 nm (pH 4,0; 25°C). Bestimmungen konnten mit einer Standardabweichung von ±1,17% durchgeführt werden.相似文献
23.
The condensation products of 5-amino-1,3-disubstituted-pyrazoles with aromatic aldehydes were identified as 2,4-dihydro-2,5-diphenyl-4-(phenylmethylene)-3H-pyrazol-5-imine derivatives Treatment of these products with mercaptoacetic acid gave new fluorine containing 1H-pyrazolo[3,4-e][1,4]thiazepin-7-ones. 相似文献
24.
Reinvestigation of the reaction of 3-aroylmethyleneindol-2-ones with hydrogen peroxide has revealed that a 1:1 isomeric mixture of spiro[3H-indole-3,2′-oxiran]-2(1H)-ones is formed. The structures of the two isomers have been confirmed by their ir, pmr and mass spectral studies. Mass fragmentation patterns of these compounds are discussed. 相似文献
25.
N. L. Chutke M. N. Ambulkar V. K. N. Singh A. N. Garg 《Fresenius' Journal of Analytical Chemistry》1994,350(12):723-726
A multielemental instrumental neutron activation analysis (INAA) method has been employed for the determination of 30 elements in seven garden soil samples from Nagpur City and two intercomparison soil standards from IAEA, Vienna and Institute of Radioecology and Applied Nuclear Techniques (IRANT), Slovak Republic. Environmental implications of elemental concentrations in different soils have been discussed. 相似文献
26.
Gamma-ray induced decomposition of solid binary mixtures of KNO3 with halides viz. KCl, KBr and KI has been studied at room temperature. G(NO
2
–
) values were found to vary with absorbed dose. Size and electronegativity of anions and molar composition of halides are the other factors influencing radiolysis. 相似文献
27.
R. G. Weginwar R. B. Lanjewar A. N. Garg 《Journal of Radioanalytical and Nuclear Chemistry》1989,134(1):173-180
A radiochemical method for the determination of gold using198Au, has been developed. It is based on the synergistic extraction of Au(III) with thionalide (TA) in ethyl methyl ketone (EMK) or isobuthyl methyl ketone (IBMK) at pH 5.0.Effect of various parameters such as pH, nature of solvent and interferences due to other radionuclides have been studied. The method can be used up to 25 ng of Au. 相似文献
28.
D. L. Samudralwar R. G. Weginwar A. N. Garg 《Journal of Radioanalytical and Nuclear Chemistry》1989,131(1):3-10
A radiochemical solvent extraction method has been developed for the determination of Mn(II) using54Mn tracer. Mn(II) is complexed with 2-thenoyltrifluoroacetone (TTA) at pH 8.5 and extracted in isobutyl methyl ketone (IBMK). Different parameters affecting the extraction, and interferences due to diverse ions have been studied. The method can be used for the determination of Mn in microgram amounts. 相似文献
29.
H. K. Wankhade D. L. Samudralwar A. N. Garg 《Journal of Radioanalytical and Nuclear Chemistry》1986,105(2):95-105
Short-term reactor irradiation followed by successive counting over long periods has been used for the nondestructive determination of more the 20 elements in geological and biological samples. The samples, along with USGS standards and NBS SRMs, were irradiated for 5 m, 10 m, 15 m, 1 h, 2.5 h, and 10 h, followed by counting on a Ge/Li/ gamma-ray spectrometer. The technique has been employed for the determination of several major, minor, and trace constituents in geological, biological and environmental samples. 相似文献
30.
Ambulkar Ms. Mamata N. Chutke N. L. Garg A. N. 《Journal of Radioanalytical and Nuclear Chemistry》1996,207(1):3-17
Instrumental neutron activation analysis (INAA) has been used for the determination of 27 elements (Ag, Au, Ba, Br, Ce, Co, Cr, Cs, Eu, Fe, Ga, Hg, Hf, K, La, Mn, Na, Sb, Sc, Se Sr, Th, P, Ta, Tb, Zn and Zr) in 15 water samples collected from different sources (reservoirs, well, borewell, sewage tank, river, rain) in and around Nagpur city (central India) including doubly distilled and a sea water sample from Bombay. Sample residues after evaporation were irradiated at a thermal neutron flux of 1012–1013 n·cm–2·s–1 for 10 min, 1d and 1wk and counted using a HPGe detector and an 4k MCA at different intervals. Several environmental standards from NIST (USA), NIES (Japan) and USGS rock were also analysed for quality assurance. Wide variations in elemental concentrations have been observed in water samples from different sources. Most elemental concentrations in drinking water from various sources, are within ISI/WHO limits. Sea water showed very high concentrations of Ba, Cr, Co, Fe, Hg, Sb, Se and Zn. For doubly distilled and rain waters, however, very low elemental concentrations of Ba, Ce, Fe, Sc, Hg, Se, Sr and Th were observed. 相似文献