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1.
G. S. Deshmukh 《Fresenius' Journal of Analytical Chemistry》1955,145(4):251-253
Summary The quantitative oxidation of thiocyanate by ceric sulphate has been studied and the method utilised for the determination of small quantities of cerium by back titrating the excess (unreacted) KSCN against standard mercuric nitrate with diphenylcarbazone as the internal indicator. Accurate results are obtained under the specified experimental conditions and the procedure is more simple and direct than that adopted during earlier studies of the above redox reaction.Grateful thanks of the author are due to Professor S. S. Joshi for facilities during the work and to the National Institute of Sciences of India for award of a Research Fellowship. 相似文献
2.
V. D. Anand J. P. Srivastava G. S. Deshmukh 《Fresenius' Journal of Analytical Chemistry》1962,191(5):321-329
Summary The polarographic behaviour of nickel and cobalt in the mixed base electrolytes, urea-pyridine and urea-hydrazine has been studied. The effect of pH, concentration of supporting electrolyte and the presence of various other ions was investigated. Well defined polarograms for both the elements were obtained at pH 6.0 and 5.0 respectively. Attempts were made to utilize these observations in the separation of the two cations. While the difference in E
1/2 of the ions in urea-pyridine was greater than –0.3 volts that in urea-hydrazine was about –0.2 volts or slightly less even under the optimum conditions. In a mixed solution the waves for Co and Ni were therefore well developed and separated in the former base electrolyte. The polarograms in urea-hydrazine were, however, of little analytical use because of the washing away of the Ni wave due to the presence of even small amounts of cobalt.
Zusammenfassung Das polarographische Verhalten von Nickel und Kobalt in Harnstoff-Pyridin- und Harnstoff-Hydrazinlösung wurde untersucht und der Einfluß des pH-Wertes, der Leitsalzkonzentration sowie der Gegenwart verschiedener anderer Ionen festgestellt. Bei pH 6,0 bzw. 5,0 wurden für beide Elemente gut ausgebildete Polarogramme erhalten. Es wurde versucht, die erhaltenen Ergebnisse zur Trennung der beiden Ionen zu benutzen. In Harnstoff-Pyridinlösung beträgt der Unterschied der beiden Halbstufenpotentiale mehr als –0,3 V und man erhält gut ausgebildete und voneinander getrennte Stufen. In Harnstoff-Hydrazinlösung dagegen beträgt der Unterschied nur –0,2 V oder etwas weniger, selbst unter optimaler Bedingungen, und die Ni-Stufe wird schon durch kleine Kobaltmengen beeinträchtigt.相似文献
3.
Consider a family of stars. Take a new vertex. Join one end-vertex of each star to this new vertex. The tree so obtained is known as abanana tree. It is proved that the banana trees corresponding to the family of stars
- (K1,1, K1,2,…, K1,t ?1, (α + l) K1,t, K1,t + 1, …, K1,n), α ? 0
- (2K1,1, 2K1,2,…, 2K1,t? 1, (α + 2)K1,t, 2K1,t + 1, …, 2K1,n), 0 ? α <t and
- (3K1,t, 3K1,2, …, 3K1,n) are graceful.
4.
Summary An amperometric titration of calcium with selenite is described. Barium, strontium, and other cations forming insoluble selenites interfere, but magnesium does not. The method is rapid and suitable for routine analysis, the error being less than 10 parts per 1000 over the range 50 to 70 mg of calcium.
Zusammenfassung Ein amperometrisches Titrationsverfahren für Calcium mit Selenit wurde beschrieben. Barium, Strontium und andere Kationen, die unlösliche Selenite bilden, stören, nur Magnesium nicht. Das Verfahren ist rasch und für Routineanalysen geeignet. Im Bereich zwischen 50 und 70 mg Calcium ist der Fehler geringer als 1% relativ.
Résumé On décrit un titrage ampérométrique du calcium par l'ion sélénite. Le baryum, le strontium et les autres cations formant des sélénites insolubles interfèrent, excepté le magnésium. La méthode est rapide et convient à l'analyse en série, l'erreur étant inférieure à 10 parties pour 1000 dans le domaine de 50–70 mg de calcium.相似文献
5.
Summary Pb, Tl, Bi and Sb yield well defined polarograms in 1 M ethylenediamine in presence of 3% mannitol, with half-wave potentials at – 0.71 V, – 0.51 V, – 0.60 V and – 1.10 V, respectively. Only Pb and Tl develop maxima which can be suppressed by 0.02% gelatin. Presence of mannitol prevents the precipitation of Pb, Bi, and Sb in the alkaline solution. Simultaneous determinations of Pb/Tl, Bi/Sb, and Pb/Sb can be carried out.
Polarographische Bestimmung von Pb, Tl, Bi und Sb in Äthylendiamin in Gegenwart von Mannit
Zusammenfassung Gut ausgebildete Polarogramme kann man von diesen Elementen in 1 M Äthylendiamin in Gegenwart von 3% Mannit erhalten. Die Halbstufenpotentiale liegen bei – 0,71 V (Pb), – 0,51 V (Tl), – 0,60 V (Bi) und – 1,10 V (Sb). Maxima, die im Falle von Pb und Tl gebildet werden, können durch 0,02% Gelatine unterdrückt werden. Durch Mannit wird die Fällung von Pb, Bi, und Sb in der alkalischen Lösung verhindert. Simultanbestimmungen von Pb/Tl, Bi/Sb und Pb/Sb sind möglich.
Our sincere thanks are due to Dr. G. B. Singh, Professor and Head, Department of Chemistry, B.H.U. for providing the necessary facilities. 相似文献
6.
Sharief Deshmukh 《Geometriae Dedicata》1991,38(2):117-120
Kaehler 2-form of 2 being exact, it gives rise to a 1-form defined on a hypersurface of 2. We show that if this 1-form defines a contact metric structure with respect to the induced metric on the compact and connected hypersurface of 2, then the hypersurface is a round sphere of radius 1.This work is supported by Research Grant No. (Math/1409/05) of the Research Center, College of Science, King Saud University, Riyadh. 相似文献
7.
Average dislocation density in a number of electrolytically coloured and uncoloured crystals of KBr and KCl has been measured
using the etch-pit technique. A decrease in density of dislocation after electrolytic colouration has been observed. This
is attributed to the change in the dislocation pattern inside the crystals during colouration to produce more number of vacancies
under the typical conditions of large electric field gradient at high temperature. 相似文献
8.
Multibeam CO2 lasers consist of a large number of closely packed parallel glass discharge tubes, all sharing a common plane parallel resonator. This paper describes construction and operation of a CW multibeam CO2 laser consisting 20 discharge tubes and cooled length of 1500 mm, delivering 1 kW power. A high-frequency pulser is used for producing preionization in all discharge sections for initiating the main DC discharge simultaneously in all discharge tubes. Plane parallel resonator consists of a plane ZnSe mirror of 90 mm diameter having 60% reflectivity and a gold-coated copper mirror of same diameter. This laser operates in waveguide regime and laser power is not critically sensitive to mirror misalignment. 相似文献
9.
Dipole-allowed single photoionization of some closed shell atoms and ions has been investigated in the relativistic random-phase
approximation (RRPA). Application of relativisticmultichannel quantum defect theory (RMQDT) is made together with RRPA to
analyse autoionizing resonances. Analysis points to the importance of interchannel coupling in high energy photoionization
and reveals various degeneracies in relativistic atomic spectra to influence the low energy dynamics. Interesting threshold
behavior in photoelectron spin polarization has been seen. Prospective future studies have been indicated. 相似文献
10.
Chintamani Mande Subha Chattopadhyay Prabodh C Deshmukh R Padma Pranawa C Deshmukh 《Pramana》1990,35(4):397-403
A new scale of electronegativity based on X-ray spectroscopic data was earlier presented by Mande and others for the elements3Li to54Xe. The present paper reports an extension of this scale carried out for most of the heavier elements lying between55Cs and92U. The present approach is based on the physical interpretation of electronegativity of an atom as the attractive electrostatic
force it exerts at a distance equal to its covalent radius. To estimate this force, experimental spectroscopic data have been
employed. The merits of such an approach have been pointed out recently by Mullay and may be of interest in the context of
the intimate relation found between electronegativity and superconducting transition temperature. 相似文献