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51.
Prabha D. Nair M. Jayabalan V. N. Krishnamurthy 《Journal of polymer science. Part A, Polymer chemistry》1990,28(13):3775-3786
Hydrophobic-hydrophilic interpenetrating polymer networks (IPNs) of polyurethane and polyacrylamide have been synthesized. The IPNs have been characterized by IR, thermal, and mechanical studies. SEM studies indicate phase mixing of some IPNs. Solvent resistance and surface hydrophilicity as evidenced by contact angle measurements suggest that these IPNs could be used for biomedical applications. 相似文献
52.
Y. K. Sharma S. N. Dolia A. Krishnamurthy B. K. Srivastava 《Hyperfine Interactions》1990,54(1-4):711-715
57Fe Mössbauer study of the pseudo-Binary alloys Fe1?xMnxSn2 for 0≤x≤1.0 reveal the antiferromagnetically ordered state at 79K for all the specimens of the series. The hyperfine field at Fe site decreases with increasing manganese concentration. Magnetic susceptibility measurements performed in the temperature range 80 K≤T≤300 K indicate that the Néel temperature decreases with increasing Mn concentration for the samples withx≤0.4 whereas it increases continuously for the specimens havingx>0.4 of the alloy series. 相似文献
53.
Electric field experiments have been carried out on +1 and -1 defects formed in alignment inversion walls, in a planarly aligned nematic phenyl benzoate. The results show that the defects are non-singular in the core and exhibit a flexoelectric response to an applied d.c. or low frequency a.c. field. When the c-director flux lines are circular, as in a +1 defect in a wall parallel to the easy axis, flexoelectro-optic switching characterized by an azimuthal angle variation is observed. When the c-director flux is radial, the response is seemingly through polar angle variations involving no rotation of the extinction brushes due to crossed polarizers. This conclusion follows from the field-induced structural distortions observed at a -1 defect having a combination of radial and tangential c-director fields. 相似文献
54.
M. V. Krishnamurthy M. S. Nagar N. S. Hon 《Journal of Radioanalytical and Nuclear Chemistry》1987,117(2):91-98
Plutonium/IV/ compounds obtained in the reactions with phenylacetic acid and -naphthyl acetic acid in the pH range of 3.5–5.0 have been isolated and studied. Carbon, hydrogen and plutonium analyses have shown that plutonium/IV/ phenyl acetate and plutonium/IV/ -naphthyl acetate have the composition Pu/OH/3/C10H7CH2COO/, respectively. Infra-red and ultra-violet absorption spectral studies and thermogravimetric analysis have corroborated these chemical formulas. 相似文献
55.
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57.
Mössbauer studies are reported on a magnesium manganite series MgxMn2.9?xFe0.1O4 for 0.5 ? x ? 2.4. In the region x ? 1.4 two quadrupole doublets are observed while for x ? 1.8 only one doublet could be observed. Quadrupole splitting (QS) has been studied as a function of x and an unusually large QS for the outer doublet has been attributed to Jahn-Teller distortion whose onset has been located in the region 1.8 > x > 1.4; this is corroborated by X-ray diffraction studies. Probable cation distributions are proposed. Oxygen ion parameters are estimated for the compositions corresponding to x = 1 (tetragonal phase) and x = 2 (cubic phase) under point charge approximation for electric field gradient at Fe3+ sites. 相似文献
58.
Two different matrix algorithms are described for the restoration of blurred pictures. These are illustrated by numerical examples. 相似文献
59.
In this article, we present a comparative study of the Raman spectra of alkali halides in relation to the lattice dynamics ofBorn andRaman. It is shown that the experimentally observed limit of the second-order spectra in almost all the cases can be explained well by the Lyddane-Sachs-Teller relation. It is also seen, while, an explanation of the second-order Raman spectrum of a crystal of diamond or zinc blende structure requires the frequencies from the critical points,W, Γ, X andL inBorn's analysis, the frequencies fromΓ, X andL alone are sufficient and necessary for an interpretation of the same onRaman's model. Some similarities in the determination of the long wave properties of crystals like elastic constants and limiting frequencies of the lattice vibrations in the symmetry directions in both the models are pointed out. 相似文献
60.
Giuseppe Giordano Krishnamurthy Shyam Alan C. Sartorelli Walter J. McMurray 《Journal of mass spectrometry : JMS》1992,27(5):633-635
Several 1,2,2-tris(sulfonyl)hydrazines, conceived as prodrugs of 1,2-bis(sulfonyl)hydrazines and synthesized as potential antineoplastic and trypanocidal drugs, were analyzed by mass Spectrometry as part of the confirmation of the structure of these compounds. Since these compounds showed activity against several transplanted animal tumors, an understanding of the mass spectral behavior of these agents is important to gain information should clinical trials and metabolic studies be undertaken. In all spectra, protonated molecular ions were observed. Collision activation resulted in considerable fragmentation in the fast atom bombardment spectra. Rearrangement ions formed by elimination of substituted diimides from the middle of the molecule were observed. Other rearrangements involving the alkyl substituent and sulfonyl oxygen also occurred. 相似文献