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41.
42.
R. P. Arshinova A. Ch. Plyamovatyi R. A. Kadyrov S. G. Gnevashev B. A. Arbusov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):449-453
Abstract The conformational behaviour of seven- and eight-membered heterocycles based on their NMR spectrum and on a theoretical investigation is described. All possible basic conformations and their quantitative parameters have been considered. A molecular mechanics approach is applied to the calculation of the multidimensional maps of potential energy dependence on torsional angles. 相似文献
43.
V. Yu. Baranovskii V. G. Ganev V. B. Petkova Kh. Ch. Voicheva M. V. Dimitrov 《Colloid Journal》2012,74(6):645-648
IR spectroscopy and viscometry data have shown that poly(acrylic acid) and poly(methacrylic acid) form complexes with agar-agar in aqueous solutions as they do with other polysaccharides. The polyacid-agar-agar complexes are typical hydrogels. The swelling index of hydrogels based on the poly(methacrylic acid)-agar-agar complex has been found to be markedly lower than that of poly(acrylic acid)-agaragar complex. The hydrogels based on the complex of cross-linked poly(acrylic acid) with agar-agar can be of practical interest as polymeric carriers for drugs. 相似文献
44.
R. Hempelmann C. J. Carlile D. Beyer Ch. Kaps 《Zeitschrift für Physik B Condensed Matter》1994,95(1):49-53
Using pulsed neutrons of 19.8 Å wavelength a quasielastic line broadening as low as 0.03 eV (FWHM) has been observed due to Na+ diffusion in the glass Na2O·2SiO2. From the linewidths a Na+ self-diffusion coefficient of 3.1·10–8 cm2/s at 420°C was obtained in excellent agreement with the diffusion coefficient determined for the same sample batch using22Na radioactive tracers. The experimental Q dependence of the quasielasic linewidths gives a hint for deviations from a purely random walk in an ionic glass. 相似文献
45.
R. Kadono J. H. Brewer K. Chow S. R. Kreitzman Ch. Niedermayer T. M. Riseman J. W. Schneider T. Yamazaki 《Hyperfine Interactions》1994,85(1):259-264
The electric quadrupole interaction of55Mn nuclei was studied in the weakly ferromagnetic system MnSi using muon level-crossing resonance (LCR) technique. The temperature dependence of the electric field gradient (EFG) shows a critical behavior near the ferromagnetic transition temperature, indicating that the EFG due to the conduction electron is strongly correlated with the magnetic susceptibility in the itinerant electron magnetism. The temperature dependence of EFG is in reasonable agreement with the self-consistent renormalization theory developed by Moriya and coworkers.We gratefully acknowledge helpful discussion with Dr. N. Nishida. We also wish to thank Keith Hoyle and Curtis Ballard for technical support. 相似文献
46.
The NMR enhancement factor of a frozenCuMn spin glass has been measured at a temperatureT?T g /5. The measurements were performed as function of static magnetic fields of different directions. A two component model of a spin glass has been outlined. One component being a “system of single spins” and the other one being a “subsystem of clusters”. Both components were attributed to different kinds of interaction being RKKY and dipole interaction respectively. The effective anisotropy field of the single spin system consists of two unidirectional contributionsH a s andH a c , which have been measured for different conditions. A second anisotropy fieldH d binds the cluster system to the system of single spins. All anisotropy fields depend on the annealing temperature of the alloys. 相似文献
47.
We discuss in full detail the basic results of the theory of subdynamics. We analyse the regularity requirements of the projective components of the resolvent in the theory and correct a recent mathematical result of M. Courbage regarding the impossibility of simultaneous analytic continuation of the collision and creation operators. We offer further some critiques on the interpretation of the various results of the subdynamics formalism. 相似文献
48.
Penelope Schobinger-Papamantellos Ch. Routsi J.K. Yakinthos 《Journal of Physics and Chemistry of Solids》1983,44(9):875-877
We have carried out neutron diffraction on a HoCo2Si2 powder sample at 4.2 K. The magnetic structure of this compound is collinear antiferromagnetic with the holmium magnetic moments parallel to the c-axis of the crystal. The magnetic moment value of holmium is 9.85 μB. The magnetic space group is I4/mm'm' (Sh410128) k = 000 The ordering temperature is tn = 12(1) K. 相似文献
49.
Let V
n
–1
n
be the adaptive process of self-normalized partial sums S
k
of independent random variables X
i
, defined by linear interpolation between the points (V
k
2/V
n
2,S
k
/V
n
), kn, where V
k
2=
ik
X
i
2. We prove that if the X
k
's are symmetric, V
n
–1
n
converges weakly to the Brownian motion W in each Hölder space supporting W
if and only if
V
n
–1 max
kn
|X
k
|=o
P
(1). We give some partial extension to the non symmetric case. 相似文献
50.
In this paper, we extend the Hölderian invariance principle of Lamperti [6] to the case of partial-sum processes based on a triangular array of row-wise independent random variables. As an application, we obtain necessary and sufficient conditions for the almost sure (resp. in probability) weak Hölder convergence of partial-sum processes based on bootstrapped samples. 相似文献