Autowave synthesis of cast aluminum oxynitrides with a high nitrogen content

Aluminum oxynitrides Al₂₂O₃₀N₂ and Al₂₃O₂₇N₅ and a number of Al-O-N solid solutions with a nitrogen content of 2.3 to 6.5 wt % were prepared from (CrO₃-Al-Al₂O₃-AlN) thermite-type mixtures with a high combustion temperature (2950–3200 K) by using the autowave synthesis method. The synthesis was conducted in a hermetically sealed reactor at an initial nitrogen pressure of 4.0 to 8.0 MPa. The aluminum nitride content was demonstrated to influence the nitrogen content in cast aluminum oxynitrides and on their microstructure and phase composition.     

Temperature sensitivity and noise of an HTSC Josephson detector on a sapphire bicrystal substrate at 77 K

In YBa₂Cu₃O_{7 − x} films grown on sapphire bicrystal substrates, the Josephson junctions are prepared based on artificial grain boundaries formed by the turn of the crystal lattices about the [100] axis. The films are deposited by the laser ablation method on the buffer CeO₂ layer. The critical film temperature reaches 88.5 K with a transition width of 1.5 K. Junctions from 2 to 3-μ m wide are integrated into the planar log-periodic antennas and their characteristics are measured at 77 K. The characteristic voltage I _c R _n reaches 570 μV. With exposure to external radiation at a frequency of 113 GHz, the Shapiro steps were observed on the current-voltage characteristic. The temperature sensitivity of this detector placed in a quasi-optical receiving unit is measured. At the modulation of the input radiation temperature 77 K/300 K, a response of more than 200 nV is observed at the detector output. At the modulation frequency, intrinsic noise is about 1 nV/Hz^1/2, which corresponds to a temperature resolution of 1 K. Original Russian Text ? M. Tarasov, E. Stepantsov, A. Kalabukhov, M. Kupriyanov, D. Winkler, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ i Teoreticheskoĭ Fiziki, 2007, Vol. 86, No. 11, pp. 828–831.     

The electromagnetic effects in <Emphasis Type="Italic">K</Emphasis><Subscript><Emphasis Type="Italic">e</Emphasis>4</Subscript> decay

The final-state interaction of pions in K _e4 decay allows to obtain the value of the isospin and angular-momentum-zero ππ scattering length a ₀ ⁰ .We take into account the electromagnetic interaction of pions and isospin-symmetry-breaking effects caused by different masses of neutral and charged pions and estimate the impact of these effects on the procedure of scattering-length extraction from K _e4 decays.     

Solvent-free deposition of hybrid halide perovskites onto thin films of copper iodide p-type conductor

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Hydrogenation of Intermetallic Compounds ACo3 (A = Ce,Y) with Hydrogen and Ammonia

Russian Journal of Applied Chemistry - The reactions of intermetallic compounds ACo3 (A = Ce, Y) with hydrogen and ammonia at 20–450°C were studied. The composition of the products and...     

Erratum to: Response of a SINIS Detector with Electron Cooling to Submillimeter-Wave Radiation

JETP Letters - Page 542, the sentence under Fig. 3 should read as follows: According to Fig. 3, the maximum radiation response is 2 × 109 V/W, which is 2.5 times greater than that at...     

Dynamics of the chain of forced oscillators with long-range interaction: from synchronization to chaos

We consider a chain of nonlinear oscillators with long-range interaction of the type 1l(1+alpha), where l is a distance between oscillators and 0相似文献   

Composite Materials with 2D Graphene Structures: Applications for Hydrogen Energetics and Catalysis with Hydrogen Participation

The work presents the results of studies concerning preparation of graphene-like nanomaterials by graphite oxide reduction, preparation of nickel-graphene catalysts, magnesium-graphene, and carbon-graphene composites. Optimum conditions for preparing these materials and their functional characteristics are determined.     

Relaxation rates of 69Ga and 71Ga nuclei in aqueous solutions

Line widths in the ⁶Li, ⁷Li, ²³Na, ³⁹K, ⁸⁵Rb, ⁸⁷Rb and ¹³³Cs N.M.R. spectra of solutions of the alkali salts of biphenyl and fluorenone are reported as a function of solvent and temperature. From a numerical analysis of the room temperature data the contribution of the various relaxation mechanisms to the line widths are established. It is shown that the results are consistent with the observed solvent and temperature dependence of the line widths. Values of the electron spin correlation time are obtained and a value of 1·6 ± 0·4 Å is found for the ‘Van der Waals radius’ of the biphenyl anion. Line width expressions for the static and the dynamic ion pair model are presented. It is demonstrated that the static ion pair model applies to solutions of caesium biphenylide. Semi-empirical rules are presented concerning the importance of various relaxation mechanisms for the different alkali nuclei in the type of solution studied here.     

Bethe subalgebras of the group algebra of the symmetric group

We introduce families $ \mathcal{B}_n^S\left( {{z_1},\ldots,{z_n}} \right) $ and $ \mathcal{B}_{{n,\hbar}}^S\left( {{z_1},\ldots,{z_n}} \right) $ of maximal commutative subalgebras, called Bethe subalgebras, of the group algebra $ \mathbb{C}\left[ {\mathfrak{S}n} \right] $ of the symmetric group. Bethe subalgebras are deformations of the Gelfand?Zetlin subalgebra of $ \mathbb{C}\left[ {\mathfrak{S}n} \right] $ . We describe various properties of Bethe subalgebras.