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81.
82.
Vaghela SS Jethva AD Gohil MS Subbarayappa A Gour PM Susarla VS Gadde R Ghosh PK 《Annali di chimica》2003,93(9-10):841-848
A textile dye effluent containing chiefly reactive azo dyes has been treated electrochemically for discoloration and COD (chemical oxygen demand) reduction at different current densities, flow rates and dilution. Experiments have been carried out in a thin electrochemical reactor under single pass conditions using a dimensionally stable catalytic anode (DSA) and a stainless steel cathode. 相似文献
83.
S. K. Das C. S. Kedari S. S. Shinde S. Ghosh U. Jambunathan 《Journal of Radioanalytical and Nuclear Chemistry》2002,253(2):235-240
The efficiency of tailor made immobilized Saccharomyces
cerevisiae(biomatrix) for the sorption of radionuclides 233U, 239Pu, 241Am, 137Ce, 144Cs, 103,106Ru and 90Sr from aqueous nitrate solutions at different pH was studied. Effect of ionic strength, anionic components, initial metal concentration and particle size of the biomatrix on the sorption of metal ions were investigated. At pH in the range of 1 to 2 more than 95% sorption of U, Pu, Am and Ce could be accomplished, while that of Ru was 65%. Sorption of Cs and Sr were negligible under similar conditions. The metal ion-biomatrix system for Pu, Am and Ce reached equilibrium within 60 minutes. In the case of U, equilibrium attained in 100 minutes. The presence of anionic components, Cl-, C2O4
2-, CH3COO-, NO3
- and SO4
2- (up to 0.5 mol.dm-3 of their individual concentration) in the aqueous solutions has no effect on the sorption of Pu by the biomatrix. Sorption of U, Pu, Am were observed in the presence of several cationic impurities such as Al, Be, Cd, Cr, Fe, Mn, Pb, Ce, Dy, Eu, Gd and Sm. Metal sorbed on the biomatrix could be leached out using 5 mol.dm-3 nitric acid. The I.R spectra of U bearing biomatrix suggest chemical interaction of uranyl ion with the biomatrix. 相似文献
84.
Kalyan Kali Sen Gupta Ambikesh Mahapatra Balaram Ghosh 《Transition Metal Chemistry》1991,16(5):500-502
Summary The reactivities of - and -glycerophosphates towards MnO
4
–
in HClO4 medium have been examined. The reactions between glycerophosphates and MnO
4
–
are first order with respect to [glycerophosphate], [MnO
4
–
] and [H+]. There is no evidence for cleavage of the C–O–P bond rather than the terminal –CH2OH group being oxidized to the respective phosphoglyceraldehyde. 相似文献
85.
86.
87.
88.
Subir Ghosh Sanpei Kageyama Rahul Mukerjee 《Annals of the Institute of Statistical Mathematics》1992,44(3):593-603
In this paper the problem of finding the design efficiency is considered when a single observation is unavailable in a connected binary block design. The explicit expression of efficiency is found for the resulting design when the original design is a balanced incomplete block design or a group divisible, singular or semiregular or regular with 1>0, design. The efficiency does not depend on the position of the unavailable observation. For a regular group divisible design with 1>0, the efficiency depends on the position of the unavailable observation. The bounds, both lower and upper, on the efficiency are given in this situation. The efficiencies of designs resulting from a balanced incomplete block design and a group divisible design are in fact high when a single observation is unavailable.The work of the first author is sponsored by the Air Force Office of Scientific Research under Grant AFOSR-90-0092.On leave from Indian Statistical Institute, Calcutta, India. The work of the third author was supported by a grant from the CMDS, Indian Institute of Management, Calcutta. 相似文献
89.
D. Ghosh J. Roy M. Basu A. Bhattacharjee T. Guhathakurta K. Sengupta 《Czechoslovak Journal of Physics》1982,32(11):1221-1224
This paper presents an extensive study on the dependence of the mean number of the fast fragment of the target nucleus n
g on the incident beam energy in proton-nucleus interaction in emulsion in the range 6·2E
0400 GeV/c. It has been observed that n
g decreases in the range 6·2E
0200 GeV/c, then increases and attains an approximately steady value up to 400 GeV/c. It is very difficult to explain this behaviour with the help of the existing nuclear production models.The author would like to thank Prof A. J. Herz (CERN), Prof. K. D. Tolostov (Dubna, U.S.S.R.), Prof. P. L. Jain (State University of New York, U.S.A.), Prof. G. Giacomelly (Italy) for kindly supplying the exposed emulsion plates. 相似文献
90.
A. Ghosh K. S. Patel R. K. Mishra 《Journal of Radioanalytical and Nuclear Chemistry》1991,152(1):243-249
A new and simple method for selective spectrophotometric determination of uranium(VI) with 4-(2-pyridylazo)resorcinol (PAR) and N-octylacetamide into benzene over pH 7.0–9.0 is described. The molar absorptivity of the complex with 9 different amides is in the range of (0.40–3.2)·104 1·mol–1·cm–1 at the absorption maximum. Out of these, the most sensitive compound N-octylacetamide (OAA) was chosen for detailed studies in the present investigation. The detection limit of the method is 0.008 g U·ml–1. The system obeys Beer's law in the range of 0–5 g U·ml–1. The method is free from interferences of most of the common metal ions except vanadium(V) and copper(II), which are masked by proper masking agents. The composition of the complex is determined by curve-fitting method. The method has been applied for the recovery of the metal from rock samples and synthetic mixtures. 相似文献