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The paper presents the results of the comparative analysis of operation modes of an autonomous hybrid power complex with/without the energy store. We offere the technique which defines the power characteristics of the main components of a hybrid power complex: the consumers of the electric power, wind power and photo-electric installations (the last ones have been constructed). The paper establishes that, in order to compensate the seasonal fluctuations of power in autonomous power systems with renewable energy resources, the accumulative devices are required, with a capacity of tens of MWh including devices that are capable to provide energy storage with duration about half a year. This allows abandoning the storage devices for smoothing the seasonal fluctuations in the energy balance.The analysis of operation modes of energy stores has shown that for a stock and delivery of energy on time intervals, lasting several hours, the accumulative devices with rather high values of charging and digit power aren't required. It allows using the lead-acid rechargeable batteries of the deep category for smoothing the daily peaks of surplus and a capacity shortage. Moreover, the analysis of operation modes of energy stores as a part of the hybrid complexes has demonstrated that in charging/digit currents of the energy store the low-frequency and high-frequency pulsations of big amplitude caused by changes of size of output power of the renewable power installations and loading are inevitable. If low-frequency pulsations (the period of tens of minutes) can partially be damped due to the restriction of size of the maximum charging current of rechargeable batteries, then it is essentially impossible to eliminate high-frequency pulsations (the period of tens of seconds) in the power systems with the only store of energy. The paper finds out that the combined energy store having characteristics of the accumulator in the modes of receiving and delivery of power on daily time intervals, and at the same time having properties of the supercondenser in the modes of reception and return of impulses of power on second intervals of time is best suited to requirements of the autonomous power complexes with renewable energy resources.

Nuclear reaction analysis online technique has been applied to study the diffusion of deuterium in metals. Investigations ensuring the application of the new method have been performed. These investigations include the development of a device for diffusion annealing of samples in the chamber of an accelerator and an algorithm for taking into account the effect of radiation defects on the diffusion coefficients. Test measurements of the diffusion coefficients of deuterium in nickel in the temperature range from 130 to–60°С have been performed. For negative temperatures, experimental data on the diffusion of a hydrogen isotope in a metal have been obtained for the first time by a direct method and it has been shown that the online nuclear reaction analysis provides reliable data.

The construction of a hermetic transport container for mounting alkaline metal samples in the vacuum chamber of an accelerator during online measurements of the deuterium diffusion coefficients in metals is described. A glass capsule containing an alkaline metal sample is unsealed in a special box with an inert gas atmosphere and the sample is placed in a cylindrical hollow at the surface of a flat metal plate of the container. After this, the hermetic transport container with the sample is fixed in place on a stationary holder inside the accelerator chamber and is unsealed after a high vacuum is attained in the chamber. Sodium samples are assessed using the nuclear reaction analysis. It is shown that the sodium purity in oxygen, carbon, and other low-Z elements meets the requirements of the accelerator technique.

The online nuclear reaction analysis technique has been applied to study the temperature dependence of deuterium diffusion coefficients for deuterium in sodium at temperatures ranging between 110 and 240 K, and at cryogenic temperatures, below 160 K, tunneling of deuterium atoms in the metal lattice has been observed. Above 160 K, diffusion occurs by the classical mechanism of overbarrier atomic jumps. Results of quantum diffusion of deuterium in a metal have been obtained for the first time; they used to be known only for the lightest hydrogen isotope, protium, in niobium and tantalum. The analysis has shown that the necessary condition for carrying out the quantum mechanism of deuterium migration is low Debye temperature of a metal, below 200 K. Experimental data on diffusion of hydrogen isotope in an alkali metal have also been obtained for the first time in this paper.

Zirconia and yttria stabilized zirconia (YSZ) have multiple uses, including catalysis, fuel cells, dental applications, and thermal coatings. We employ nuclear reaction analysis to determine elemental composition of YSZ nanoparticles synthesized by laser evaporation including 18O studies to distinguish between oxide and adsorbed oxygen content as a function of surface area. We see dramatic deviation from stoichiometry that can be traced to loss of oxygen from the oxide near the surface of these nanopowders. Density functional calculations are coupled with these experimental studies to explore the electronic structure of nonstoichiometric surfaces achieved through depletion of oxygen. Our results show oxygen-depleted surfaces present under oxygen potentials where stoichiometric, oxygen-terminated surfaces would be favored thermodynamically for crystalline systems. Oxygen depletion at nanopowder surfaces can create effective two-dimensional surface metallic states while maintaining stoichiometry in the underlying nanoparticle core. This insight into nanopowder surfaces applies to dissimilar oxides of aluminum and zirconium indicating synthesis conditions may be more influential than the inherent oxide properties and displaying need for distinct models for nanopowders of these important engineering materials where surface chemistry dominates performance.

Alumina's importance has motivated detailed exploration of α-Al 2 O 3 (0001). Under certain conditions, this surface undergoes a (√31 × √31)R9° reconstruction resulting in a layer of aluminum, Al(111), over a stoichiometric substrate. γ-Al 2 O 3 is less understood but dominates material applications. We show that γ-Al 2 O 3 nanopowders present aluminum-enriched surfaces similar to those of the reconstructed α-Al 2 O 3 (0001). Employing nuclear reaction analysis supported by density functional calculations, we quantitatively identify the elemental composition of γ-Al 2 O 3 and find a transition to pure aluminum termination.

Room-temperature measurements of diffusion coefficients for deuterium in proton conductors La0.9Sr0.1ScO3 -δ and BaZr0.9Y0.1O3 -δ which contain dissolved H2O vapor have been performed. The concentration of oxygen structure vacancies in oxides after treatment in vapor was close to zero. A diffusion source of deuterium was created by ion implantation; measurement of the concentration–distance distribution of deuterium in samples was performed in situ during implantation. The NRA technique and 2H(d,p)3H reaction at an energy of the incident beam of 650 keV were used. For the initial and boundary conditions of the diffusion problem which were realized in the work, a solution of the inhomogeneous Fick equation was obtained. Using the technique developed, measurements of the diffusion coefficients for hydrogen in proton conductors were for the first time performed directly. For the BaZr0.9Y0.1O3 -δ oxide, the directly gained values of diffusion coefficients agree rather well with those obtained from the proton conductivity with the use of Nernst–Einstein equation.

The first results of studying the electrical properties of thin silicon carbide (SiC) layers grown on silicon using a new method of solid-phase epitaxy are presented. The type of carriers in these SiC/Si films is determined, and their concentration and mobility are measured. SiC films grown by the proposed method on Si substrates possess n-type conductivity. The concentration of majority carriers (electrons) in undoped SiC layers amounts on average to n ∼ 1018 cm−3, and their mobility varies within μ = 27–85 cm2/(V s), depending on the regime of synthesis.

InSb crystals doped with manganese within the critical concentration of metal-insulator transition (Ncr = 2×1017 cm-3) demonstrate colossal negative magnetoresitance and Hall constant sign inversion at low temperatures in magnetic field – unusual for nonmagnetic materials. Studies of the magnetotransport and conductivity dependency on temperature and manganese concentration revealed that both holes and electrons influence the effects. An excitonic insulator phase conception is proposed as a new approach for the explanation of conductivity and magnetotransport anomalies in p-InSb(Mn). (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Results are presented from numerical simulations of mass-transfer and combustion processes in the furnace of a BKZ-420-140-2 boiler using the applied program package FIRE 3D with replacement of the design Ekibastuz coal by Kuznetsk grade D hard coal and Irsha-Borodino grade 2B lignite.

In Mn-doped InSb single crystals an unusual, for nonmagnetic semiconductors, dependence on manganese concentration have been revealed for magnetization, conductivity, magnetoresistance and the Hall effect in the range NMn= (1÷2)×1017cm-3. Noticeable low temperature magnetization increase was observed at NMn≈1×1017cm-3. Strong correlation between magnetization, specific resistivity, Colossal Magnetoresistance (CMR) and the Hall constant as a function of manganese concentration in InSb(Mn) was revealed on the insulating side of the metal-insulator transition at Ncr=2×1017cm-3 and at temperature below 10K. Simultaneously, an onset of ferromagnetic-like response in the magnetic moment measurements of p-InSb(Mn) at NMn≤Ncr= 2×1017 cm-3 was registered. This experimental evidence fits the pattern of triplet excitons switching off from conductivity and demonstrates weak magnetic ordering. The coincidence in transport, magnetotransport properties of p-InSb(Mn) and uniaxially stressed p-InSb(Ge) crystals puts forward the idea that the unusual InSb(Mn) properties could be related to Jahn-Teller distortions caused by Mn.

The major equipment in the PGU-230 steam-gas unit at the Heller thermal power plant (Hungary) and its technical characteristics are described. The technologies for startup of the power production system of the steam-gas unit and for switching it from a steam-gas unit cycle to open cycle operation of the steam-gas unit and vice versa are discussed. The regulatory range of the power generation system and its maneuverability characteristics are determined.

Completely self-consistent ab initio calculations of scattering of electrons between the lowest minima of the conduction band by short-wavelength phonons are performed for the first time for a group of А III В V semiconductor crystals. The structure constants, electron and vibrational spectra, and probabilities of scattering are calculated for the crystals from unified positions within the electronic density functional method. The theory does not involve any phenomenological assumptions on positions of minima in the conduction band, effective carrier masses, interatomic forces, or scattering probabilities. The electron-phonon coupling constants (the deformation potentials) for actual Γ−X, Γ−L, and X−L transitions for scattering between the nonequivalent X−X and L−L valleys in the conduction bands of AlP, AlAs, AlSb, GaP, GaAs, GaSb, InP, InAs, and InSb crystals with sphalerite structure are calculated. Results obtained are compared with theoretical calculations within the phenomenological rigid ion model and with those performed by the selfconsistent frozen phonon method.

The fully self-consistent first-principles calculations of electron scattering from short-wavelength phonons between lower valleys in the conduction band of a silicon crystal are carried out for the first time. The calculations of the lattice constant, the electron and phonon spectra, and the scattering probabilities are performed in the framework of a unified approach within the electron density functional theory. The theory contains no phenomenological assumptions regarding the relative position of minima in the conduction band, effective masses of carriers, interatomic forces, and scattering probabilities. The electron-phonon coupling constants (deformation potentials) for symmetry-allowed f and g transitions are calculated. The calculated constants lie in the range of values measured in different experiments involving intervalley transitions in silicon.

We report magnetotransport investigation of nonmagnetic InSb single crystal doped with manganese at Mn concentration NMn ~ 1,5 × 1017 cm−3 in the temperature range T = 300 K–40 mK, magnetic field B = 0–25T and hydrostatic pressure P = 0–17 kbar. Resistivity saturation was observed in the absence of magnetic field at temperatures below 200 mK while applied increasing external magnetic field induced colossal drop of resistivity (by factor 104) at B ~ 4T with further gigantic resistivity increase (by factor 104) at 15T. Under pressure, P = 17 kbar, resistivity saturation temperature increased up to 1,2 K. Existing models are discussed in attempt to explain resistivity saturation, dramatic influence of magnetic field and pressure on resistivity with the focus on possible manifestation of three dimensional Wigner crystal formed in InSb by light electrons and heavy holes.

Experimental data on the nonstationary heat exchange under a controlled heat load are presented. Investigations were carried out with cut plates specially formed to shape, on which the distribution of the heat-flow density is near-exponential (from the periphery to the center). Empirical dependences of the critical density of a heat flow and the heat-transfer coefficient on the rate of heating have been obtained.

We discover a new universal long-range interaction between solid objects in polymer media. This polymer-induced interaction is directly opposite to the van der Waals attraction. The predicted effect is deeply related to the classical Casimir interactions, providing a unique example of universal fluctuation-induced repulsion rather than normal attraction. This universal repulsion comes from the subtracted soft fluctuation modes in the ideal counterpart of the real polymer system. The effect can also be interpreted in terms of subtracted (ghost) large-scale polymer loops. We establish the general expressions for the energy of polymer-induced interactions for arbitrary solid particles in a concentrated polymer system. We find that the correlation function of the polymer density in a concentrated solution of very long chains follows a scaling law rather than an exponential decay at large distances. These novel universal long-range interactions can be of importance in various polymer systems. We discuss the ways to observe/simulate these fluctuation-induced effects.

Transport properties of manganese-doped InSb crystals with hole concentration close to the critical concentration Ncr of the metal–insulator transition (MIT) in p-InSb(Mn) was found to be different from MIT in semiconductors doped with non-magnetic impurities such as p-Ge(Ga), p-Si(P) and p-InSb(Ge). On the insulator side of the transition (NMn ≤ Ncr = 2 × 1017 cm–3) in the range of hole concentration p = 1–2 × 1017 cm–3 an activation type of conductivity with energy gap Δ = 7 × 10–6–10–3 eV was observed. Thus, the usually observed variable range hopping conductivity in crystal semiconductors doped with non-magnetic impurities at low and super-low temperatures was not revealed in p-InSb(Mn) at p ≤ Ncr. An external magnetic field decreased Δ and caused a giant decrease of specific resistivity (ρ0/ρB ∼ 104 at T ≤ 0.3 K and B ≥ 3 T). On cooling to temperatures below T = 1.5 K the Hall constant changed sign at B < 3 T. The change of Hall constant sign with decrease of temperature means that conductivity of p-InSb(Mn) and crystals compensated with Te – p-InSb(Mn, Te) – at low temperatures was caused by electrons. The proposed model associated an activation energy Δ at p ∼ Ncr with the energy gap between sub-bands formed in the impurity band. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Results of experimental investigation of the influence of the operating time of a heating surface on the intensity of heat transfer in the kerosene and water boiling on it are presented. The experimental data on the heat transfer in the indicated liquids boiling on unrun heating surfaces have been generalized using different relations.

Results of experimental investigations of the influence of a long stay of the heat‐release surface in kerosene on the first critical density of the heat flux in boiling under the steady‐state and step conditions of heat release are given.

The stress induced giant negative magnetoresistance (GNMR), q 0 /q B ∼ 10 2 , in p-Ge and p-InSb single crystals is studied. Temperature dependence investigation shows that GNMR is caused by the decrease of impurity conduction energy in magnetic field. The proposed model describes this effect as the reduction of exchange interaction energy between charge carriers in the antiferromagnetically ordered impurity band.

The author presents results of experimental investigations of the effect of prolonged stay of the heattransfer surface in water on the first critical density of the heat flux in boiling under steady and stepwise heat-release conditions.

Studies of a classical III–V semiconductor (InSb) doped with 3d magnetic ions (Mn2+, having a localized spin S=55/2) reveal some unexpected transport properties. It is found that the transition from the metallic to the low-temperature insulator phase occurs at an impurity concentration NMn∼Ncr=2× 1017 cm−3 and a temperature T

We have studied experimentally the magneto-transport properties of type-II broken-gap Ga1 − xInxAsSb/p-InAs heterostructures with various doping levels of the quaternary layer by Te or Zn. A strong electron channel with high electron mobility was observed at the interface of the heterostructures. Interface roughness scattering was found to dominate the electron mobility atT = 4.2–47 K in samples with an undoped or a slightly doped quaternary layer. A drastic mobility drop with increasing Zn doping level was observed. Shubnikov–de Haas oscillations at low temperatures (1.5–20 K) were studied and a weak anisotropy of magnetoresistance was found. Some important parameters of the heterostructures under study were determined.

The anomalous Hall effect is considered in a system of magnetic impurities on the example of the nonmagnetic semiconductor InSb: Mn. From an analysis of the Hall constant as a function of impurity (Mn) concentration, temperature, and magnetic field strength the magnetic susceptibility of the system and the magnetic ordering temperature, T ≈ 1 K, are determined. A physical model is proposed giving a qualitative explanation of the anomalous Hall effect in a system of magnetic impurities. It is argue that the exchange interaction at the boundary for the metal–insulator transition in a system of magnetic impurities damps Coulomb fluctuations. In einem System magnetischer Fremdatome wird der anomale Hall-Effekt betrachtet, mit dem nichtmagnetischen Halbleiter InSb: Mn als Beispiel. Aus del Analyse der Hall-Konstanten als Funktion von Fremdatomkonzentration (Mn), Temperatur und Magnetfeldstarke werden die magnetische Suszeptibilitat und die magnetische Ordungstemperatur (T ≈ 1 K) bestimmt. Es wird ein physikalisches Modell zur Erklarung vorgeschlagen. Austauschwechselwirkung an der Grenze des Metall–Halbleiter-Uberganges dampft in einem System magnetischer Fremdatome die Coulomb-Fluktuationen.

The use of the proposed type of DFR for stabilizing the speed of an independent microHES provides rather good dynamic indices of the power plant and stable operation of the station with almost any type of turbines. To provide the required accuracy of regulating the speed of the unit, the parameters of the DFR should be selected in conformity with the recommendations given above.

Thermoresistors made of InSb(Mn) for use at ultra-low temperatures are described. Below 10 mK they have higher thermosensitivity than other known thermoresistors, with a relatively low specific resistance. They have a logarithmic dependence of specific resistance on temperature and negative magnetoresistance. The magnetic Mn 2+ impurity in the non-magnetic semiconductor InSb is supposed to cause a magnetic gap in the impurity band owing to exchange interaction between manganese ions and holes. This effect increases for compensated p-InSb(Mn).

Autoballast systems of stabilizing the operating regime of (microHESs) are presently becoming rather widespread [1, 2]. Among their virtues are maximum simplicity of the hydraulic structures in which are used mechanically unregulated turbines or pumps operating in a turbine regime, good speed of response providing stabilization of the output voltage with a sufficient accuracy, and possibility of using general-purpose quantity-produced equipment, which makes it possible to construct comparatively cheap energy sources. The most important element of the microHESs under consideration, which provides the necessary quality of the ac voltage being generated, is the system of regulating the ballast load connected to the generator output in parallel to its main electrical load. The ballast load provides constancy of the operating regime of the turbine--generator--load system regardless of disturbing effects, the main one of which is a change in the power of the useful electrical load of the station. The regulators of the autoballast are usually made with semiconductor devices, most often with thyristors. Optimization of the parameters of the autoballast system is possible only on the basis of a system approach with consideration of the characteristics of all elements figuring in a microHES: turbine, generator, electrical load, and stabilization devices. An important problem, on the solution of which depend the weight--size indices of the unit, its cost, and regulating characteristics, is the selection of the type of generator. An analysis of the working conditions of a microHES shows that an autonomous operating regime is more simply realized for synchronous machines. This is determined by the fact that the weight--size and cost indices of induction generators with a capacitor bank necessary for its self-excitation are commensurate with the indices of synchronous generators, and the voltage regulating systems of synchronous machines are considerably simpler and cheaper [1]. The behavior of such a system is described by a system of nonlinear differential equations of a high order, which can be written in the form [1]

Gorham's disease, also called massive osteolysis or vanishing bone disease, is an enigmatic condition caused by endothelial proliferation occurring in bone and soft tissue. Death is frequent when there is spinal or visceral involvement. We present a case of spinal and skull base Gorham's disease that was reversed by radiation therapy administered while the spine was supported by a halo vest. The literature is reviewed.

An investigation is carried out on the properties of the electron channel in a broken-gap isotypic type II GaInAsSb/p-InAs heterostructure and their dependence on the doping level of the quaternary solid solution with a donor (Te) and an acceptor (Zn). The Hall mobility decreases (by more than two orders of magnitude) with increasing acceptor concentration. The Shubnikov-de Haas oscillations are observed at low temperatures (T=1.5–20 K) and the electron effective mass is determined (m n=0.026m 0), along with some other parameters of the heterostructure.

Immunoglobulins were modified by diethylenetriaminepentaacetic acid anhydride and sulfosuccinimidy 16-(biotinamido) hexanoate and were conjugated with modified polylysine. Biodistribution of the samples was observed before and after avidin injection. Samples containing no polylysine accumulate in reticuloendothelial system, protein conjugate with polylysine concentrate in kidneys. The results demonstrate that drug distribution depends on the type of modification.

Polyclonal monospecific antibodies to the glial fibrillar antigen of the brain (GFA) and, as controls, antibodies not possessing specific tendency were injected intravenously separately into two groups of rats with glioblastomas transplanted into the brain. The immunoenzymatic method was used to study the content of the injected antibodies in tissue extracts collected from the zone of the glioblastoma, brain matter and other organs 2, 20, and 48 hours after the injection. It was established that polyclonal monospecific antibodies to GFA accumulate selectively in the zone of the glioblastoma. The use of antibodies to GFA for selective transport of medicinal agents to malignant glial tumors must be evaluated in further studies.

The level of specific alpha 1-globulin (S alpha 1-GB) and autoantibodies to it was measured by the immunoenzyme method in blood serum of 160 donors and 88 neurological patients. The S alpha 1-GB level was increased most frequently in blood serum of patients with glial brain tumors. In malignant glial tumors the increased serum S alpha 1-GB level was combined with a reduced level of autoantibodies to it. The work discusses the role of the suggested immunochemical tests and the mechanisms of the increase in the S alpha 1-GB level and decrease in the level of autoantibodies to this antigen.

Specific alpha 1-globulin of the brain was assayed by an immunoenzyme technique in blood sera from cases of various brain pathologies and healthy donors. Relative elevation in brain specific alpha 1-globulin level, as compared with that in healthy subjects, was more frequent in patients with malignant glial tumors of the brain, less frequent in cases of benign glial tumors and in very few patients suffering from other brain diseases. Raised level of specific alpha 1-globulin may be caused by disorders in the blood-brain barrier or lesions in brain or tumor tissues which is peculiar to glial malignancies of the brain. The said test offers much advantage in diagnosis of glial tumors.

By immunochemical methods the most high concentrations of alpha-1 organ specific antigen of the brain were revealed in tissue extracts of the spinal marrow, cerebral trunk, hypothalamus; its lower concentrations--in the cerebral cortex, cerebellum, optic nerve, white substance of the hemispheres and pineal gland. This protein was not found in the hypophysis. In tumors of neuroectodermal origin the antigen was found in high concentrations. In an group of meningiomas alpha-1 organ specific brain antigen was detected in tumors of meningotheliomatous type, but it was absent in tumors of mixed and fibroblastic type, this permitted suggesting a neuroectodermal origin of tumors of the first type and ectomesenchymal one of the second type.