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991.
Summary The authors have examined many inorganic solids like bentonite, carbonates, sulphates, sulphides, oxychlorides, phosphates,
arsenates, and arsenites of metals, as emulsifying agents and found that they all give coarse emulsions but some of them give
quite stable emulsions and may be useful for technical application. The bentonite stabilised emulsions are initially very
fine and in one month the change in globule size is rather small but in the second month the deterioration is rather rapid
due to some changes in its structure. Carbonates are far superior to sulphates, which have little or no emulsification property.
There are distinct regions of maximum degree of dispersion brought about by precipitation at either very high or very low
concentration of the solid. The finer the dispersion the better the emulsifying properties as is clearly seen in the case
of bismuth oxychloride. The arsenates and arsenites of calcium and aluminium are very good agents. It may probably be due
to the fact that slow hydrolysis produces gelatinous precipitate or fine particles of carbonates formed by the action of air.
Emulsions stabilised by aluminium arsenite or calcium arsenate may be used as insecticides, as arsenic compounds are highly
toxic to all forms of animal life. 相似文献
992.
Cs. M. Buczkó S. Mukherjee Z. Dezső M. Hegedüs M. Várady 《Journal of Radioanalytical and Nuclear Chemistry》1976,29(2):295-300
The determination of the titanium content of bauxite samples of various origin was studied by thermal neutron activation and
X-ray analysis. A252Cf-fission neutron source and a Ge(Li) detector as well as a3H exciting source and a Si(Li) detector were used in the investigations. Within equal measuring times and with a sample weight
of 8 g the sensitivity of the activation method is 0.35 w% Ti with an absolute statistical error less than 10%, while that
of the X-ray method is 0.06 w% Ti and the absolute statistical error does not exceed 5%. 相似文献
993.
S Mukherjee 《Pramana》1986,27(5):623-628
We investigate the strong limit of an operator valued sequence used in other form in the nonrelativistic theory of multichannel
scattering, and also some of its consequences. 相似文献
994.
The tricyclic dienediones 5,6 and 7 have been synthesised for entry into the ring systems of the tetracyclic diterpenes atisirene (1), phyllocladene (3) and hibaene (4) respectively. 相似文献
995.
The paper deals with the study of propagation of Love waves and reflection as well as transmission of SH waves under initial shear stresses. The results have been computed taking two real media and presented graphically to compare with the initial stress-free cases. 相似文献
996.
Synthesis and spectroscopic characterisation (IR, mass, PMR) of 2-guanidino 4,6-dimethyl pyrimidine (GPym) and 2-phenyl guanidino 4,6-dimethyl pyrimidine (PG-Pym) are reported. Complexation of the title ligands with nickel(II) salts in moisture-free condition furnish complex species of the type: Ni(GPym)2X2[X = Cl, Br, SCN and NO3] and Ni(PGPym)2X2 [X = Cl, Br, I and SCN]. Physico-chemical characterisation of the complex species have been made from molar conductance data, magnetic susceptibility measurements, electronic and vibrational spectra. Magnetic and electronic spectral features suggest a pseudo-octahedral environment of the central Ni(II) ion in all these complexes. IR spectra have furnished positive information regarding the bonding sites of the ligand molecules (namely, the pyrimidyl nitrogen and the imino nitrogen of the guanidine residue) and the mode of the attachment of the counterion(X) to the metal ion. 相似文献
997.
998.
G. P. Mukherjee 《Czechoslovak Journal of Physics》1972,22(3):177-180
The radial displacement of an annular piezoelectric ceramic disc with concentric electrodes has been found with the help of transform calculus when the external periphery is subjected to a time-dependent force.1B, Bankim Chatterjee Street, Calcutta-12, West Bengal, India.The author is grateful to Dr. R. R. Giri of Jadavpur University for his kind help and guidance in the preparation of this paper. 相似文献
999.
Decrease in ampicillin fluorescence values (Ex. 385 nM, Em. 460 nM) were correlated with the increase in the pUC 19 plasmid-encoded -lactamase activity of Escherichia coli DH5. The fluorescence data were then utilized for the development of a computer program in MS DOS Q BASIC to predict the -lactamase activity. 相似文献
1000.
A generalization of the notion of almost complex structure is defined on a nonorientable smooth manifold M of even dimension. It is defined by giving an isomorphism J from the tangent bundle TM to the tensor product of the tangent bundle with the orientation bundle such that JJ=–Id
TM
. The composition JJ is realized as an automorphism of TM using the fact that the orientation bundle is of order two. A notion of integrability of this almost complex structure is defined; also the Kähler condition has been extended. The usual notion of a complex vector bundle is generalized to the nonorientable context. It is a real vector bundle of even rank such that the almost complex structure of a fiber is given up to the sign. Such bundles have generalized Chern classes. These classes take value in the cohomology of the tensor power of the local system defined by the orientation bundle. The notion of a holomorphic vector bundle is extended to the context under consideration. Stable vector bundles and Einstein–Hermitian connections are also generalized. It is shown that a generalized holomorphic vector bundle on a compact nonorientable Kähler manifold admits an Einstein–Hermitian connection if and only if it is polystable. 相似文献