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91.
The amorphous ferromagnetic glass-coated microwires with positive magnetostriction constant of the metallic core possess the bistable magnetization reversal and the fast domain wall propagation along the microwire axis. These properties and also the magnetization processes in the systems of the microwires are of interest in the magnetic sensing technology, encoding systems and smart composite applications. In this work we present the results of the experimental investigation, simulations and theoretical estimations of the hysteresis process in the systems of the magnetically bistable microwires with different length and positional relationship between them. The location of the short microwires near the long microwire affects the switching fields (external coaxial magnetic field applied for starting of the domain wall propagation along the microwire axis) and the hysteresis process. The changes of these properties are not directly proportional to the value of the shorter microwire shift along the longer one. When the short microwire was placed in the middle of the long one and when the one end of the long microwire coincided with the end of the short one, the two-steps hysteresis loops were observed for both sample orientations: before and after sample rotation on 180°. When the short microwire was placed close to the end of the long microwire (but did not coincide with it) we observed at first the two-steps hysteresis loop and single step behavior for one branch of the hysteresis loop after sample rotation. Moreover, changing of the orientation of the samples results in the shift of the switching field of the shorter microwire when its end was located near the end or coincided with the end of the longer one. This uncommon hysteresis behavior was explained and illustrated using results of the simulations. The values of microwires interaction were also estimated. 相似文献
92.
V. ARÁMBULA-VILLAZANA M. SOLACHE-RÍOS M. T. OLGUÍN 《Journal of inclusion phenomena and macrocyclic chemistry》2006,55(3-4):237-245
Many factors may affect the heavy metals sorption on natural zeolites among them the temperature, for this reason in this paper the cadmium retention behavior on Mexican zeolitic rich tuff as a function of temperature is considered. The kinetic and the isotherms were determined at 303, 318, and 333 K, the remaining cadmium in the solution samples was analyzed by atomic absorption spectrometry. The pseudo-second order rate constant, k, as well as the apparent diffusion coefficients were calculated from the cadmium uptake by the zeolitic rock as a function of the contact time and temperature, the highest amounts were found for the experiments done at 333 K. The maximum cadmium adsorption capacity by the zeolitic material was 12.2 mg Cd2+/g at 318 K corresponding to 20% of the effective ion exchange capacity of the Chihuahua zeolitic rock. In order to explain the cadmium sorption behavior different kinetics and isotherm models were considered. 相似文献
93.
E. V. Kotova V. A. Kudinov E. V. Stefanyuk T. B. Tarabrina 《Russian Mathematics (Iz VUZ)》2018,62(8):27-37
Using additional unknown functions and additional boundary conditions in the integral method of heat balance, we obtain approximate analytic solutions to the non-stationary thermal conductivity problem for an infinite solid cylinder that allow to estimate the temperature state practically in the whole time range of the non-stationary process. The thermal conducting process is divided into two stages with respect to time. The initial problem for the partial differential equation is represented in the form of two problems, in which the integration is performed over ordinary differential equations with respect to corresponding additional unknown functions. This method allows to simplify substantially the solving process of the initial problem by reducing it to the sequential solution of two problems, in each of them additional boundary conditions are used. 相似文献
94.
In this paper the relation betweenEP--matrices andE
k
P--matrices over an arbitrary filedF is studied. Further, conditions for the product ofE
k
P--matrices to be anE
k
P--matrix and for the reverse order law to hold for the polynomial Moore-Penrose inverse of the product ofE
k
P--matrices are determined 相似文献
95.
K. A. Lyssenko D. G. Golovanov V. I. Meshcheryakov A. R. Kudinov M. Yu. Antipin 《Russian Chemical Bulletin》2005,54(4):933-941
The character of electron density distribution in the C2B3 open face, the influence of the SMe2 group on the character of electron density distribution, and the nature of the sodium—anion interaction were studied based
on the data of high-resolution X-ray diffraction study of crystals of the sodium salt of charge compensated nido-carborane [9-SMe2-7,8-C2B9H10]− and quantum-chemical calculations for the Na...H—B bonded dimer, the isolated [9-SMe2-7,8-C2B9H10]− anion, and the [7,8-C2B9H10]2− dianion. The character of electron density distribution in the C2B3 open face is analogous to the electron distribution in the cyclopentadienyl ligand. In nido-carborane, a substantial charge redistribution takes place compared to that observed in the closo analogs. The topological analysis of the electron density distribution function demonstrated that the cation—anion interactions
are determined predominantly by Na...H—B contacts. The total energy of these contacts in the { [9-SMe2-7,8-C2B9H10]Na(thf)2}2 dimer estimated from X-ray diffraction data is 11.74 kcal mol−1.
Dedicated to Corresponding Member of the Russian Academy of Sciences E. P. Serebryakov on the occasion of his 70th birthday.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 911–918, April, 2005. 相似文献
96.
MK Hossain-Ibrahim K Rezajooi JK MacNally MRJ Mason AR Lieberman PN Anderson 《BMC neuroscience》2006,7(1):8-21
Background
Inflammation around cell bodies of primary sensory neurons and retinal ganglion cells enhances expression of neuronal growth-associated genes and stimulates axonal regeneration. We have asked if inflammation would have similar effects on corticospinal neurons, which normally show little response to spinal cord injury. Lipopolysaccharide (LPS) was applied onto the pial surface of the motor cortex of adult rats with or without concomitant injury of the corticospinal tract at C4. Inflammation around corticospinal tract cell bodies in the motor cortex was assessed by immunohistochemistry for OX42 (a microglia and macrophage marker). Expression of growth-associated genes c-jun, ATF3, SCG10 and GAP-43 was investigated by immunohistochemistry or in situ hybridisation. 相似文献97.
A. V. Kudinov Yu. G. Kusraev I. A. Merkulov K. V. Kavokin I. G. Aksyanov B. P. Zakharchenya 《Physics of the Solid State》2003,45(7):1360-1373
The behavior of the optical-orientation signal under resonant optical excitation of localized excitons in quantum wells with semimagnetic layers was studied both experimentally and theoretically. The most remarkable experimental observation made in this study is the increase in the degree of polarization of the quantum well radiation in the conditions in which the Hanle effect is observed. The behavior of magnetically induced circular luminescence polarization in a slightly tilted field (quasi-Voigt geometry) also appears unusual. Possible specific contributions to the optical exciton orientation in semimagnetic nanostructures are discussed. A theoretical model is proposed which, while being based on the well-known concepts of collective spin dynamics of magnetic ions in the exchange field of a photoexcited hole, takes into account fluctuations of the local magnetization. The calculations agree quantitatively with experiment for reasonable values of the parameters. 相似文献
98.
Siberian Mathematical Journal - We study the possibilities of defining some operations on fields via the remaining operations. In particular, we prove that multiplication on an arbitrary field can... 相似文献
99.
A. R. Kudinov D. V. Muratov M. I. Rybinskaya P. V. Petrovskii 《Russian Chemical Bulletin》1997,46(3):559-567
A number of earlier unknown tri- and tetranuclear organometallic clusters of group VIII transition metals was synthesized
by the addition of coordinatively unsaturated species to a single metal-metal bond. A number of novel heteronuclear clusters,
CpCp
2
′
Rhm2(μ−CO)3(μ3−CO), (Cp′=Cp, Cp*; M2=Ru2, Fe2; RuFe); Cp2Cp
2
*
Rh2M2(μ3−CO)3 (M = Ru, Fe); , Cp3Cp*Rh3M(μ3−CO)2(μ3−d) (M = Ru, Fe); Cp2Cp
2
*>
Rh2Co2(μ3−CO)2,etc., was obtained.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 579–586, March, 1997. 相似文献
100.
L. S. Shul’pina E. L. Durova Yu. N. Kozlov A. R. Kudinov T. V. Strelkova G. B. Shul’pin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(12):1996-2000
It is found that ferrocene in the presence of small amounts of pyrazine carboxylic acid (PCA) effectively catalyzes the oxidation of benzene to phenol with hydrogen peroxide. Two main differences upon the oxidation of two different substrates, i.e., cyclohexane and benzene, with the same H2O2-ferrocene-PCA catalytic system are revealed: the rates of benzene oxidation and hydrogen peroxide decomposition are several times lower than the rate of cyclohexane oxidation at close concentrations of both substrates, and the rate constant ratios for the reactions of oxidizing particles with benzene and acetonitrile are significantly lower than would be expected for reactions involving free hydroxyl radicals. The overall rate of hydrogen peroxide decomposition, including both the catalase and oxidase routes, is lower in the presence of benzene than in the presence of cyclohexane. It is suggested on the grounds of these data that a catalytically active particle different from the one generated in the absence of benzene is formed in the presence of benzene. This particle catalyzes hydrogen peroxide decomposition less efficiently than the initial complex and generates a dissimilar oxidizing particle that exhibits higher selectivity. It is shown that reactivity of the system at higher concentrations of benzene differs from that of an initial system not containing an aromatic component with the capability of π-coordination with metal ions. 相似文献