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The effect of the increase in relative humidity on the change in the number concentration of fine airborne particles in a closed sealed chamber is studied in the paper. This work was carried out within the scope of a series of works of the SIRIUS international project. The project is aimed at studying the dynamics of aerosol accumulation in the air environment of sealed inhabited objects using methods for assessing the level of aerosol contamination worked out in cleanroom technology. A qualitative result of the relationship between the number concentration of the airborne particles and the relative humidity inside the closed chamber in the absence of other sources of particle generation was obtained. This result correlates with the experimental data obtained during the SIRIUS four-month isolation experiment and lays the foundation for preparing for new isolation experiments of the SIRIUS project. [ABSTRACT FROM AUTHOR]

Activated resistivity, ρ(T), and positive magnetoresistance (MR) are observed in Cu2ZnSnS4 single crystals within the temperature interval between T ∼ 2 and 300K in pulsed magnetic fields of B up to 20 T. Between T ∼ 50 and 150 K, the charge transfer is described by the Mott variable-range hopping (VRH) transport over localized states of the defect acceptor band with width W ∼ 12-25 meV. Up to the highest applied fields, MR follows the law ln ρ(B) ∞ B² pertinent to the VRH conduction at λ ⪢ a, where λ is the magnetic length and a is the localization radius. The joint analysis of the MR and ρ(T) data yielded a series of microscopic parameters, including the values of a ≈ 22-45 Å, depending on the proximity of a sample to the metal-insulator transition. However, below T ∼ 3-4K the Shklovskii-Efros VRH conduction is observed. Here, the behavior of MR changes drastically, exhibiting a sharp contraction of the quadratic MR region and transformation of the MR law into those of ln ρ (B) ∞ B2/3 or / B3/4 when B is increased. In addition, such behavior of MR is accompanied by a dramatic increase of the localization radius a ≈ 50-170 Å. Both anomalies above are explained quantitatively by the same reason, connected to the constructive interference of different paths arising from multiple scattering of hopping carriers at low temperatures. In particular, the low-temperature values of the localization radius, evaluated in frames of the theory of interference phenomena in the VRH conduction, exhibit a reasonable agreement with the experimental data. [ABSTRACT FROM AUTHOR]

We present results of experimental studies of high-field magnetoresistance of Co–SiO2, Co–LiNbO3, CoNbTa–SiO2 nanocomposites with metal volume fraction close to the percolation threshold. The nanocomposite films were deposited onto a glass-ceramic substrate by ion-beam sputtering at the growth temperature not exceeding 80°C. Magnetization was measured using a superconducting quantum interference device (SQUID) magnetometer in the temperature range of 4.2–300 K. Out-of-plane magnetoresistance was measured in a pulsed magnetic field up to 20 T in the temperature range of 4.2–300 K with the pulse duration of 11–12 ms. In addition to negative magnetoresistance, a linear positive contribution to magnetoresistance was observed in high magnetic fields for nanocomposites with the composition close to the percolation threshold. This effect was explained by the influence of the Zeeman effect on the tunnel barrier height. It is shown that the unconventional anisotropy of magnetoresistance of Co–LiNbO3 is associated with the peculiarities of its microstructure. [ABSTRACT FROM AUTHOR]

We study the conductivity and magnetoresistance of the α‴ phase solid solution of (Cd1−xZnx)3As2 (x = 0.45). Single crystals of (Cd1−xZnx)3As2 are obtained by the modified Bridgman method. The space group and tetragonal lattice parameters of single crystals are found to be I41/amd and a = b = 8.56(5) Å, c = 24.16(6) Å. The temperature dependence of the conductivity and magnetoresistance is studied in the temperature range of 1.6–320 K and in the presence of a transverse magnetic field from 0 to 10 T. Mixed conductivity is analyzed using Hall resistivity data and standard quantitative mobility spectrum analysis. The concentration and mobility of holes are determined at different temperatures. The presence of two types of holes with different mobilities is demonstrated in the temperature range of 1.6–19 K, while with increasing temperature, just one type of charge carrier is observed in the mobility spectrum. [ABSTRACT FROM AUTHOR]

The effect of BaZrO3 (BZO) dopant concentration on superconducting properties in YBa2Cu3O6+x thin films is investigated in a wide magnetic field range up to 30 T. Based on the magnetization and resistivity measurements, the optimal BZO concentration for flux pinning is found to be 4% up to 20 T and increasing up to around 8% in higher fields. This result is qualitatively explained by a model where more BZO is needed in order to organize optimal columnar defect structure at high fields because the amount of single BZO particles acting as isotropic point pinning centers is increased, especially in high BZO concentrations. This means that for applications of thin film or coated conductor structures carried out at high magnetic fields, even higher dopant concentration than used in a low-field range should be produced in order to attain the optimal flux pinning conditions. [ABSTRACT FROM AUTHOR]

Abstract: It is shown that the transport properties of graphitized silicon carbide are controlled by a surface graphene layer heavily doped with electrons. In weak magnetic fields and at low temperatures, a negative magnetoresistance is observed due to weak localization. A crossover in the magnetoresistance from weak localization to weak antilocalization (the latter is the manifestation of the isospin in graphene) is observed for the first time in samples of this kind at elevated temperatures. A pronounced pattern of Shubnikov-de Haas oscillations is observed in strong magnetic fields (up to 30 T). This pattern demonstrated fourfold carrier spectrum degeneracy due to the double spin and double valley degeneracies. Also, the manifestation of the Berry phase is observed. The effective electron mass is estimated to be m* = 0.08m0, which is characteristic of graphene with a high carrier concentration. [ABSTRACT FROM AUTHOR]

Resistivity of La[sub 0.7-δ]Ca[sub 0.3]Mn[sub 1-y]Fe[sub y]O[sub 3] (LCMFO) with y = 0-0.05, δ = 0 and 0.017 is investigated between 4.2-350 K, showing that La vacancies increase the effect of Fe doping by influencing electronic states through additional microscope disorder. The Shklovskii-Efros variable-range hopping conductivity, governed by generation of a soft parabolic gap in the spectrum of localized states due to Coulomb interaction between charge carriers, is observed both above and well below the ferromagnetic-to-paramagnetic transition temperature. Our results give evidence for absence of a true metal-insulator transition both in undoped material and in LCMFO. [ABSTRACT FROM AUTHOR]

The resistivity, ρ( T), and the magnetoresistance (MR) of CuZnSnS (CZTS) single crystals are investigated at temperatures T = 2-300 K in pulsed magnetic fields of B up to 20 T. The Mott variable-range hopping (VRH) conductivity over localized states of the defect acceptor band is observed between T ~ 50-150 K. The Shklovskii-Efros (SE) VRH conduction over the states of the Coulomb gap is found below T ~ 3-4 K. The positive MR is observed at all temperatures and magnetic fields, its value decreasing with T. In the Mott VRH conduction region, MR follows the law ln ρ( B) ∝ B up to the highest applied fields. The joint analysis of the resistivity and MR data in this region has yielded values of the localization radius as well as a set of important microscopic parameters, including the mobility threshold in the acceptor band, the values of the density of localized states near the Fermi level and the critical concentration of the metal-insulator transition. In the SE region, the MR law above is observed only in much smaller fields, transformed into those of lnρ( B) ∝ B or ∝ B when B increases. Such transformation, accompanied by a strong increase of the localization radius, give evidence for an important role of scattering and interference phenomena in the VRH conduction at low temperatures. [ABSTRACT FROM AUTHOR]

Diluted magnetic semiconductor InSb:Mn exhibits a ferromagnetic behavior up to T ∼ 600 K due to presence of nanosize MnSb precipitates [Kochura et al., J. Appl. Phys. 113, 083905 (2013)]. Transport properties of InSb:Mn, including the resistivity, the magnetoresistance (MR), and the Hall effect, are investigated between T ∼ 1.6 and 300 K in magnetic fields B up to 15 T. The resistivity, ρ( T), displays an upturn with lowering the temperature below T ∼ 10-20 K attributable to the Kondo effect, where the universal Kondo behavior is observed. The Hall resistivity, ρH, demonstrates a nonlinear dependence on B up to T ∼ 300 K, suggesting an anomalous contribution due to the effect of the MnSb nanoprecipitates. The relative MR, Δ ρ( B)/ ρ(0), is positive (pMR) above T ∼ 10 K and transforms into a negative one (nMR) with lowering temperature. The Hall effect and pMR are interpreted simultaneously with the two-band model, addressed to presence of the two types of holes with quite different concentrations and mobilities. The dependences of nMR on B and T follow those of the Khosla-Fischer model, taking into account damping of the spin-dependent scattering of charge carriers in magnetic field. [ABSTRACT FROM AUTHOR]

Transport properties of polycrystalline (In, Mn)Sb samples are investigated. Behavior of the temperature and magnetic field dependencies of the resistivity, anomalous Hall coefficient and magnetoresistivity at low temperatures points out the influence of Mn complexes, Mn ions and nano- and microsizes MnSb precipitates on charge transport. [ABSTRACT FROM AUTHOR]

The high anisotropy of the critical current density in the high-temperature superconductor YBa2Cu3O6+x can be compensated by changing the pinning landscape, for example, through doping with BaZrO3. We measure the change due to BaZrO3 doping in the effective electron mass anisotropy, γ, by resistive measurements of the upper critical field in pulsed high magnetic fields. It is found that the angular dependence of the upper critical field follows the Blatter scaling up to 30 T but the irreversibility field does not. We also report a significant reduction in the effective electron mass anisotropy from 6.0 to 3.4 by BaZrO3 doping. [ABSTRACT FROM AUTHOR]

This paper describes the growth of tubular polycrystalline 3 C-SiC samples by chemical vapor deposition (CVD). The use of propionitrile as a precursor for nitrogen doping ensures the growth of polycrystalline 3 C-SiC layers with a 1000°C resistivity of 0.1-0.2 Ω cm and zero temperature coefficient of resistance. Such 3 C-SiC tubes can be used as silicon carbide electric heaters. [ABSTRACT FROM AUTHOR]

We have studied the effect of silicon-enriched vapor phase composition, deposition temperature, and CHSiCl precursor concentration on the microstructure, resistivity, and compressive strength of 3 C-SiC layers and optimized the conditions for the growth of polycrystalline 3 C-SiC layers possessing high resistivity and compressive strength. [ABSTRACT FROM AUTHOR]

Dilute magnetic semiconductors based on manganese-doped Zn0.9Cd0.1GeAs2 solid solution with various doping levels were synthesized. Their Curie point in 5-T magnetic field was 349 K. Ferromagnetic ordering in these semiconductors was due to MnAs nanoclusters, whose sizes were 3.7–3.8 nm. [ABSTRACT FROM AUTHOR]

Single crystals of the solid solutions CdGeAs2:Mn( x) and Cd0.964Zn0.036GeAs2:Mn( x) have been grown by the vertical Bridgman method. An X-ray diffraction study has demonstrated that Cd0.964Zn0.036GeAs2 ( I), Cd0.964Zn0.036GeAs2:Mn (1.5 wt%) ( II), and Cd0.964Zn0.036GeAs2:Mn (2.18 wt %) ( III) retain the CdGeAs2 structure (tetragonal system, space group I $$\bar 4$$ 2 d). The unit cell parameters of the solid solutions are as follows: a = b = 5.934(1) Å, c = 11.219(2) Å for I; a = b = 5.919(1) Å, c = 11.204(2) Å for II; and a = b = 5.918(1) Å, c = 11.208(2) Å for III. Many of Mn atoms in II and III occupy interstitial sites in the crystal lattice. Selected electrical and magnetic properties of single crystals of CdGeAs2:Mn( x) are discussed. [ABSTRACT FROM AUTHOR]

Thin YBa2Cu3O6+x (YBCO) films are prepared by pulsed laser deposition (PLD) from pure micro- (μ) and nanocrystalline (n) targets and a n-target optimally doped with 3.9 wt% BaZrO3 (BZO). Effects of target grain size and doping on superconducting (SC) properties of the films are investigated using a SQUID magnetometer up to 5 T and transport measurements in pulsed magnetic fields up to 30 T. In comparison with μ-films, clearly increased values of jc are observed in n-films. Optimal doping with BZO still increases this difference in high magnetic field range and lengthens the low-field plateau of jc(B) and increases the accommodation field B* which are typically around 110 mT, 160 mT and 500 mT at 5 K in μ, n- and BZO-doped films, respectively. Transport measurements at T > 65 K show significant improvement of irreversibility line (IRL) and jc(B) in films prepared from n-target and BZO-doped target. These improvements of the superconducting properties in high magnetic fields make pure and BZO-doped n-films attractive for high field applications. [ABSTRACT FROM AUTHOR]

The article discusses religious knowledge, objective knowledge of religion, and science in the post-Soviet period. Fundamental questions about the philosophical and methodological foundations of the study of religion are investigated and given explanations. Since the compulsory official philosophy was abolished, religion studies started under conditions of pluralism of scientific theories.

We report on magnetic-field dependences of Hall coefficient and resistivity for InN films grown by plasma-assisted molecular beam epitaxy. The Hall coefficient rises with the magnetic field. This anomalous behavior is discussed in terms of the presence of highly conducting inhomogeneities in the films. According to the magnetic field and temperature dependences of the film resistivity, the inhomogeneities are attributed to metallic indium nanoparticles formed presumably around extended defects within the InN epilayers, at their surface and the InN/GaN interface. Good correlation is observed between the growth conditions of the InN films and their electrical properties recalculated using the model. [ABSTRACT FROM AUTHOR]

The article reports on the effect of magnetic field on low-cycle fatigue. Researchers deal with a new phenomenon associated with the strong dependence of fatigue damages on magnetic-field intensity. This phenomenon is of interest from the standpoint of metal physics, is important in technological applications, and represents one of the manifestations of magnetoplastic effects. It seems likely that weakening the interaction between dislocations and a paramagnetic impurity must result in a longer dislocation path and a larger concentration of the dislocations at stopping points. As a result, the fatigue damages under deformation must be accumulated for a shorter time, and a failure of sample must also occur more often. However, due to the unknown structure of paramagnetic defects and the complex character of dislocation--defect interaction, it is possible to evaluate neither the magnitude of the effect nor even its sign.