Ultra-relativistic electrostatic Bernstein waves

A new general form of the dispersion relation for electrostatic Bernstein waves in ultra-relativistic pair plasmas, characterized by a−1 = kBT/(mec2)  1, is derived in this paper. The parameter Sp = aΩ0/ωp, where Ω0 is the rest cyclotron frequency for electrons or positrons and ωp is the electron (or positron) plasma frequency, plays a crucial role in characterizing these waves. In particular, Sp has a restricted range for permitted wave solutions; this range is effectively unlimited for classical plasmas, but is significant for the ultra-relativistic case. The characterization of these waves is applied in particular to the presence of such plasmas in pulsar atmospheres

Topological gravity on plumbed V-cobordisms

An ensemble of cosmological models based on generalized BF-theory is constructed where the role of vacuum (zero-level) coupling constants is played by topologically invariant rational intersection forms (cosmological-constant matrices) of 4-dimensional plumbed V-cobordisms which are interpreted as Euclidean spacetime regions. For these regions describing topology changes, the rational and integer intersection matrices are calculated. A relation is found between the hierarchy of certain elements of these matrices and the hierarchy of coupling constants of the universal (low-energy) interactions. PACS numbers: 0420G, 0240, 0460Comment: 29 page

Properties of equations of the continuous Toda type

We study a modified version of an equation of the continuous Toda type in 1+1 dimensions. This equation contains a friction-like term which can be switched off by annihilating a free parameter \ep. We apply the prolongation method, the symmetry and the approximate symmetry approach. This strategy allows us to get insight into both the equations for \ep =0 and \ep \ne 0, whose properties arising in the above frameworks are mutually compared. For \ep =0, the related prolongation equations are solved by means of certain series expansions which lead to an infinite- dimensional Lie algebra. Furthermore, using a realization of the Lie algebra of the Euclidean group $E_{2}$, a connection is shown between the continuous Toda equation and a linear wave equation which resembles a special case of a three-dimensional wave equation that occurs in a generalized Gibbons-Hawking ansatz \cite{lebrun}. Nontrivial solutions to the wave equation expressed in terms of Bessel functions are determined. For \ep\,\ne\,0, we obtain a finite-dimensional Lie algebra with four elements. A matrix representation of this algebra yields solutions of the modified continuous Toda equation associated with a reduced form of a perturbative Liouville equation. This result coincides with that achieved in the context of the approximate symmetry approach. Example of exact solutions are also provided. In particular, the inverse of the exponential-integral function turns out to be defined by the reduced differential equation coming from a linear combination of the time and space translations. Finally, a Lie algebra characterizing the approximate symmetries is discussed.Comment: LaTex file, 27 page

Use of Vanadium for Low-alloy Steel Manufacturing at JSC “EVRAZ NTMK”

Joint Stock Company “EVRAZ Nizhniy Tagil Metallurgical Plant” ( JSC “EVRAZ NTMK”) is the World’s largest processor of vanadium-rich titanium magnetite ores. This work describes the results of the research performed to test various combinations of vanadium and nitrogen microalloying targeted at repeatable quality and strength properties of the rolled steel products. In particular the benefits are described of using vanadium mass fractions in steel for manufacturing railway steel (rails, wheels, rings/tires), railcar body products (Z-beams, I-beams, etc.), API grades including large diameter X70 and X80 pipes. To optimize the analysis of different steel grades for the shaped sections manufacturing EVRAZ NTMK has taken efforts to identify the impact of the vanadium mass fraction in steel grade 09G2S on the mechanical properties of rolled steel with the elements of various thickness. During the effort, the mechanical tests were performed, the extent of vanadium reduction in the form of carbonitrides during the rolling and cooling process and its impact on the mechanical properties, the macrostructuring of rolled products was also studied. Recommendations were given on the chemical composition of steel 09G2S for manufacturing rolled steel of strength classes 375 and 390. Keywords: EVRAZ NTMK, vanadium, I-beams, mechanical properties, impact strengt

Frameworks for Formation and Stability of Kurgan Regional Arboretum Phytocenosis

The article is devoted to solving the problem of biodiversity conservation in the framework of increasing sustainability of natural plant communities in arboretum being an artificial protected area. Research and application have accumulated significant knowledge on various aspects of the above problem, specifically, preserving biodiversity including vegetation, monitoring biodiversity and preserving phytocenosis, plant interaction in phytocenosis, causes of disturbed biodiversity and reducing phytocenosis stability, etc. The research objective is to theorize the frameworks for phytocenosis formation, identify the factors influencing phytocenosis stability, conduct observations and experimental research on the factors affecting the formation and stability of the Kurgan regional arboretum phytocenosis. The models of the way different factors influence the resistance mechanisms of the Kurgan regional arboretum phytocenosis are built as a result of studying research materials and differ from the theoretical model in the fact that the proven distinctions were found in the ratio of limiting and background factors reflecting their regional character

Effects of cadmium and glucose on microbial communities: Revealing of the leading factor

© 2016, International Journal of Pharmacy and Technology. All rights reserved.Anthropogenous activity leads to accumulation in the soil of metals which often come to it along with organic matter. In the conditions of a laboratory experiment response of soil microbial community to an individual and simultaneous importation of glucose and cadmium is investigated. Changes of microbial community characterized by the following parameters – the common microbial biomass, respiratory activity and growth characteristics of soil community. It is established that the importation of cadmium and glucose renders multidirectional effects. At simultaneous influence of available organic matter and metal of change of the analysed parameters depend on a ratio and concentration of connections. The cluster analysis of the obtained data demonstrates that at the studied concentration of cadmium and glucose a major factor, in charge of formation of communities, metal whereas organic matter plays the supporting role is

Silicon Avalanche Pixel Sensor for High Precision Tracking

The development of an innovative position sensitive pixelated sensor to detect and measure with high precision the coordinates of the ionizing particles is proposed. The silicon avalanche pixel sensors (APiX) is based on the vertical integration of avalanche pixels connected in pairs and operated in coincidence in fully digital mode and with the processing electronics embedded on the chip. The APiX sensor addresses the need to minimize the material budget and related multiple scattering effects in tracking systems requiring a high spatial resolution in the presence of a large occupancy. The expected operation of the new sensor features: low noise, low power consumption and suitable radiation tolerance. The APiX device provides on-chip digital information on the position of the coordinate of the impinging charged particle and can be seen as the building block of a modular system of pixelated arrays, implementing a sparsified readout. The technological challenges are the 3D integration of the device under CMOS processes and integration of processing electronics.Comment: 13th Topical Seminar on Innovative Particle and Radiation Detectors IPRD1

Orthogonal Decomposition of Some Affine Lie Algebras in Terms of their Heisenberg Subalgebras

In the present note we suggest an affinization of a theorem by Kostrikin et.al. about the decomposition of some complex simple Lie algebras ${\cal G}$ into the algebraic sum of pairwise orthogonal Cartan subalgebras. We point out that the untwisted affine Kac-Moody algebras of types $A_{p^m-1}$ ($p$ prime, $m\geq 1$), $B_r, \, C_{2^m}, D_r,\, G_2,\, E_7,\, E_8$ can be decomposed into the algebraic sum of pairwise or\-tho\-go\-nal Heisenberg subalgebras. The $A_{p^m-1}$ and $G_2$ cases are discussed in great detail. Some possible applications of such decompositions are also discussed.Comment: 16 pages, LaTeX, no figure

On the Completeness of the Set of Classical W-Algebras Obtained from DS Reductions

We clarify the notion of the DS --- generalized Drinfeld-Sokolov --- reduction approach to classical ${\cal W}$-algebras. We first strengthen an earlier theorem which showed that an $sl(2)$ embedding ${\cal S}\subset {\cal G}$ can be associated to every DS reduction. We then use the fact that a \W-algebra must have a quasi-primary basis to derive severe restrictions on the possible reductions corresponding to a given $sl(2)$ embedding. In the known DS reductions found to date, for which the \W-algebras are denoted by ${\cal W}_{\cal S}^{\cal G}$-algebras and are called canonical, the quasi-primary basis corresponds to the highest weights of the $sl(2)$. Here we find some examples of noncanonical DS reductions leading to \W-algebras which are direct products of ${\cal W}_{\cal S}^{\cal G}$-algebras and `free field' algebras with conformal weights $\Delta \in \{0, {1\over 2}, 1\}$. We also show that if the conformal weights of the generators of a ${\cal W}$-algebra obtained from DS reduction are nonnegative $\Delta \geq 0$ (which isComment: 48 pages, plain TeX, BONN-HE-93-14, DIAS-STP-93-0

Classical A_n--W-Geometry

This is a detailed development for the $A_n$ case, of our previous article entitled "W-Geometries" to be published in Phys. Lett. It is shown that the $A_n$--W-geometry corresponds to chiral surfaces in $CP^n$. This is comes out by discussing 1) the extrinsic geometries of chiral surfaces (Frenet-Serret and Gauss-Codazzi equations) 2) the KP coordinates (W-parametrizations) of the target-manifold, and their fermionic (tau-function) description, 3) the intrinsic geometries of the associated chiral surfaces in the Grassmannians, and the associated higher instanton- numbers of W-surfaces. For regular points, the Frenet-Serret equations for $CP^n$--W-surfaces are shown to give the geometrical meaning of the $A_n$-Toda Lax pair, and of the conformally-reduced WZNW models, and Drinfeld-Sokolov equations. KP coordinates are used to show that W-transformations may be extended as particular diffeomorphisms of the target-space. This leads to higher-dimensional generalizations of the WZNW and DS equations. These are related with the Zakharov- Shabat equations. For singular points, global Pl\"ucker formulae are derived by combining the $A_n$-Toda equations with the Gauss-Bonnet theorem written for each of the associated surfaces.Comment: (60 pages