Spherically symmetric inhomogeneous dust collapse in higher dimensional space-time and cosmic censorship hypothesis

We consider a collapsing spherically symmetric inhomogeneous dust cloud in higher dimensional space-time. We show that the central singularity of collapse can be a strong curvature or a weak curvature naked singularity depending on the initial density distribution.     

Tuning the morphology and magnetic properties of single-domain SrFe8Al4O19 particles prepared by a citrate auto-combustion method

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Weak localization in bilayer graphene

We have performed the first experimental investigation of quantum interference corrections to the conductivity of a bilayer graphene structure. A negative magnetoresistance--a signature of weak localization--is observed at different carrier densities, including the electroneutrality region. It is very different, however, from the weak localization in conventional two-dimensional systems. We show that it is controlled not only by the dephasing time, but also by different elastic processes that break the effective time-reversal symmetry and provide intervalley scattering.     

Quantum channel for states of light as based on integrals of motion

A method based on integrals of motion for collective processes has been proposed for constructing physical schemes in which the state of one of the subsystems is insensitive to interaction. Decoherence-free quantum channels that allow transmission of an arbitrary light state including the Fock state through an absorbing medium are considered as an example.     

Observation of Spin and Valley Splitting of Landau Levels under Magnetic Tunneling in Graphene/Boron Nitride/Graphene Structures

Resonance magnetic tunneling in heterostructures formed by graphene single sheets separated by a hexagonal boron nitride barrier and bounded by two gates has been investigated in a strong magnetic field, which has allowed observing transitions between spin- and valley-split Landau levels with various indices belonging to different graphene sheets. An unexpected increase with the temperature in the interlayer tunneling conductance owing to transitions between the Landau levels in strong magnetic fields cannot be explained by existing theories.     

Effects of plasmonic absorption of terahertz radiation in silica nanocomposite doped with erbium silicate

This paper studies terahertz transmission spectra of silicon and erbium silicides which can be used to create uncooled bolometers for terahertz frequency domain.     

CVD graphene vs. highly ordered pyrolytic graphite for use in electroanalytical sensing

We explore and contrast the electroanalytical performance of a commercially available CVD grown graphene electrode with that of edge- and basal-plane pyrolytic graphite electrodes constructed from highly ordered pyrolytic graphite for the sensing of biologically important analytes, namely β-nicotinamide adenine dinucleotide (NADH) and uric acid (UA). We demonstrate that for the analytes studied here, in the best case, the electroanalytical performance of the CVD-graphene mimics that of edge plane pyrolytic graphite, suggesting no significant advantage of utilising CVD-graphene in this context.     

Adsorption-induced Depression of the Strength of Potassium Chloride Grains under the Action of Fatty Amines and Water

The surface activity of higher aliphatic amines and their salts at the interface between their solutions and air, oil, and KCl grains and their influence on the strength characteristics, moisture absorption, and caking of the grains were studied.     

9-Alkenylcarbazoles. 6. Synthesis and structure of cis-9-propenylcarbazoles

A number of cis-9-propenylcarbazoles were synthesized in good yields by isomerization of 9-allylcarbazoles by the action of tert-BuOK in dimethyl sulfoxide. It was established that cis-9-propenylcarbazole is less thermodynamically stable than its trans isomer. It was shown by¹³C NMR, UV, and IR spectroscopy that the effect of p-π conjugation in cis-9-propenylcarbazole decreases as compared with the trans isomer as a result of the noncoplanarity of the C=C bond and the carbazole ring. See [1] for communication 5. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 340–343, March, 1980.     

Construction of the extremal function for a functional on the classH ω (n)

For a functional on the classH _ω ⁽ⁿ⁾ ,n≥3, we construct the extremal function on which the upper bound obtained by A. I. Stepanets is attained. Translated fromMatematicheskie Zametki, Vol. 61, No. 4, pp. 519–529, April, 1997. Translated by N. K. Kulman