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61.
62.
63.
The structure, chemical composition, and magnetic properties of electrochemically deposited nanocrystalline Co-Ni-Fe films
were investigated using a number of techniques. A high saturation magnetic induction up to B
s
= 21 kG was attained. An enhancement of the saturation magnetization compared to the ideal anticipated one was revealed,
which correlated with the nonlinear behavior of the structural phase composition and lattice parameters with the change of
the composition.
The text was submitted by the authors in English. 相似文献
64.
N. I. Golovina G. N. Nechiporenko G. G. Nemtsev G. P. Dolganova V. P. Roshchupkin D. B. Lempert G. B. Manelis 《Russian Journal of Applied Chemistry》2007,80(1):24-30
Methods for phase stabilization of ammonium nitrate were sought for in order to considerably expand the application area of this oxidizing agent in various-purpose self-combustible formulations, including that in a new generation of gas-generating formulations for automobile air bags. New methods for stabilization of ammonium nitrate were studied and, in particular, a search was made for organic compounds that can stabilize ammonium nitrate even at their low content. The mechanism of phase state stabilization of ammonium nitrate by compounds of this kind was examined. 相似文献
65.
G. Panina 《Central European Journal of Mathematics》2003,1(2):157-168
All 3-dimensional convex polytopes are known to be rigid. Still their Minkowski differences (virtual polytopes) can be flexible
with any finite freedom degree. We derive some sufficient rigidity conditions for virtual polytopes and present some examples
of flexible ones. For example, Bricard's first and second flexible octahedra can be supplied by the structure of a virtual
polytope. 相似文献
66.
A combination of 1,3-dihalo-5,5-dimethylhydantoin (X = Br, Cl) and sodium nitrite in the presence of wet SiO2 was used as an effective nitrosating agent for the nitrosation of N,N-dialkyl amines to their corresponding nitroso derivatives under mild and heterogeneous conditions in good to excellent yields. 相似文献
67.
The paper discusses the applicability of quasi-crystalline approximation to describing the thermal motion of water molecules in their normal and supercooled states. The problem is subjected to the critical analysis of experimental data on incoherent scattering of slow neutrons based on theories developed by Singwi-Sjolander [1] and Oskotsky [2] modified to duly take into account the limited applicability range of diffusion approximation. The applicability conditions of quasi-crystalline approximation are shown to be consistently satisfied only when water is in supercooled state and within a narrow temperature range above the melting temperature. 相似文献
68.
Demixing during film casting of blends of polystyrene, polymethylmethacrylate, and a symmetric diblock copolymer of styrene and methylmethacrylate is discussed. The concentration fluctuations in the homogeneous solutions were calculated in mean field approximation. The structures in the homogeneous and demixed solutions and in the dry films were measured by small-angle x-ray scattering, and the morphologies of the dry films were characterized by transmission electron microscopy. The structure of the dry blends is evidently already pre-formed in solution. 相似文献
69.
D. J. Plazek C. A. Bero S. Neumeister G. Floudas G. Fytas K. L. Ngai 《Colloid and polymer science》1994,272(11):1430-1438
By making creep and recoverable creep measurements of a nearly monodisperse low molecular weight poly(methyl phenyl siloxane) sample, we have found on decreasing temperature towardsT
g that there is continuously a change in the viscoelastic spectrum concomitant with a decrease of the steadystate recoverable compliance. This behavior is exactly the same as previously observed in low molecular weight poly(styrene), proving that this spectacular anomaly in the viscoelasticity of low molecular weight polymers is general and deserves an explanation. Photon correlation spectroscopic measurements performed on the same sample have extended the observation of the viscoelastic response to shorter times and the result corroborates the trend of variation established by the creep data.Dedicated to Prof.Dr. E. W. Fischer on his 65th Birthday. Prof.Dr. Fischer is known for his valuable contribution to fosterine, international collaboration of research in polymer science. This work is an example of his contribution because it would not be possible without him bringing us together. One of us (KLN) would like to take this opportunity to thank Prof. Dr. Fischer for his unwaiving support of the 1st (Crete) and the 2nd (Alicante) International Discussion Meeting on Relaxations in Complex Systems 相似文献
70.
Experimental data on the effect of thallium and sodium impurities on the lattice heat conductivity of PbTe at room temperature
are reported. Because the lattice of lead chalcogenides is strongly polarized near charged impurities, the effect of impurities
on the lattice heat conductivity depends substantially on their charge state. This property of the material has been used
to determine the charge state of the thallium impurity in PbTe. The results obtained argue for a model of quasi-local thallium-impurity
states which assumes low electron-correlation energy at an impurity center.
Fiz. Tverd. Tela (St. Petersburg) 40, 1206–1208 (July 1998) 相似文献