The minimal conformal O(N) vector sigma model at d=3

For the minimal O(N) sigma model, which is defined to be generated by the O(N) scalar auxiliary field alone, all n-point functions, till order 1/N included, can be expressed by elementary functions without logarithms. Consequently, the conformal composite fields of m auxiliary fields possess at the same order such dimensions, which are m times the dimension of the auxiliary field plus the order of differentiation.Comment: 15 page

Synaptic transmission as a cooperative phenomenon in confined systems

In this review paper, the theory of synaptic transmission (ST) was developed and discussed. We used the hypothesis of isomorphism between: (a) the cooperative behavior of mediators --- acetylcholine molecules (ACh) and cholinoreceptors in a synaptic cleft with binding into mediator-receptor (AChR) complexes, (b) the critical phenomena in confined binary liquid mixtures. The systems of two (or three) nonlinear differential equations were proposed to find the change of concentrations of ACh, AChR complexes, and ferment acetylcholinesterase. The main findings of our study: the linear size of the activation zone was evaluated; the process of postsynaptic membrane activation was described as a cooperative process; different approximations of ACh synchronous release were examined; stationary states and types of singular points were studied for the proposed models of ST; the nonlinear kinetic model with three order parameters demonstrated a strange-attractor behavior.Comment: 12 pages, 1 figur

Direct evidence for a piezoelectriclike effect in coherently strained SiGe/Si heterostructures

A hybrid acoustic spectroscopy technique has been used to demonstrate the (reversible) conversion of high frequency electric fields into longitudinal acoustic waves within a modulation-doped pseudomorphic Si/Si0.88Ge0.12/Si heterostructure. This provides compelling evidence for the existence of a piezoelectriclike coupling within such structures

Kinetics of Twinning and Dislocation Slip During Cyclic Deformation of ZK30 Magnesium Alloy

The present study clarifies the anisotropy of tension-compression behaviour during the cyclic deformation of ZK30 magnesium alloy. Some details of mechanical twinning and dislocation slip are studied by acoustic emission technique and direct video observations. Through the combination of these methods, the overall effect of deformation mechanisms is determined for each loading direction and their effect on the cyclic deformation is highlighted

Aerobic solid-state fermentation of the solid fraction of pig slurry

Current expansion in the pig number in Russia and their concentration in separate locations contribute to higher environmental risks. One key risk factor is the slurry produced. To utilize it more efficiently, many pig farms introduce its solid-liquid separation. The study objective was to explore the feasibility of accelerated aerobic solid-state fermentation of the solid fraction of pig slurry in closed installations. The stable thermophilic process under the temperature above +55 °C achieves shorter processing time of 3–4 days. To date, however, there is no representative evidence of such an experience. Four options of fermented mixture composition were tested based on two types of the solid fraction of pig slurry: Type 1 fraction coming from a screw separator and Type 2 fraction coming from a decanter centrifuge. The fermenter operating modes were tested in the authors’ previous studies associated with processing of the solid fraction of cattle manure and bedding poultry manure. The intensity measure of fermentation was the temperature reached by the processed material in the fermenter. Under the investigated operation modes, the stable temperature was observed for nine days in the mesophilic process: 20 °С to 55 °С; in some cases, the transition to the thermophilic process – above 55 °С was recorded. Adding the catalytic components to the processed material accelerated the substrate self-heating and a higher temperature up to 59 °С was reached. This suggests that the considered operating modes of the fermenter were suitable for the fermentation of the specified substrate

Anisotropic thermoelectric properties of Bi1.9Lu0.1Te2.7Se0.3 textured via spark plasma sintering

An onset of intrinsic conductivity observed above Td ≈ 410 K results in appearance of maxima in the temperature dependences of the specific electrical resistivity, the Seebeck coefficient and the thermoelectric figure-of-merit coefficient and minimum in the temperature dependence of the total thermal conductivity. The intrinsic conductivity is harmful for the thermoelectric efficiency enhancement since thermal excitation of the electron-hole pairs reduces the Seebeck coefficient and increases the thermal conductivit

Variation in the mass and moisture content of solid organic waste originating from a pig complex during its fermentation

The focus of the study was the fermentation of an organic waste mixture originating from a pig-rearing complex. The organic waste was processed in the laboratory-scale drum fermenter. Through the fermentation process, the fermented material was weighed by a system of four strain gauges installed under the fermenter. In our previous study, the following initial mixture characteristics were justified to have the fermentation process going – 65% to 70% moisture content and 400–600 kg m-3 density. The optimal operation mode of the fermenter was identified depending on the initial mixture composition – aeration frequency of 5 min h-1 ; air consumption of 11.3 m3 h -1 per 1.7 m3 of the fermenter volume; drum rotation interval – three times every 12 hours. Under this operating mode, the mass loss was 3% already on the third fermentation day and 7% – on the fifth day. As a result, the mass of the finished organic fertiliser was 9% smaller than that of the loaded mixture. The moisture content of the processed material also decreased: under the average moisture content of the loaded mixture of 68.7%, the average moisture content of the organic fertiliser was 66.4%. Based on the resulting experimental data, the mathematical models describing the dependence of the mass and moisture content of the processed material on the fermentation time were created. The study outcomes allow concluding that the solid-state aerobic fermentation is one of the promising options for the utilisation of the solid fraction of pig slurry

Ebonex-Supported PtM Anode Catalysts for PEM Water Electrolysis

The work presents a research on the preparation of Pt-based bimetallic catalysts dispersed on commercial Magnelli phase titania (Ebonex@) by sol gel method and investigation of their activity toward the oxygen evolution reaction (OER) in polymer electrolyte membrane water electrolysis (PEMWE). The catalytic support is also used for preparation of a carbon-free gas diffusion layer (ET30) integrated in the oxygen electrode of the membrane electrode assembly (MEA). The performance characteristics of MEA with PtM/Ebonex on ET30 are investigated in a laboratory PEMWE and compared to those of MEA with commercial carbon-based GDL with the same anode catalyst. It is proven that the chemical nature and electron density of the second metal have an essential effect on the catalyst surface structure and properties, including the lattice parameter, particle size, and electronic surface state state which in turn, reflect on the electrochemical behavior and catalytic activity. The catalysts PtCr/Ebonex and PtMn/Ebonex having deficiency of electrons in the valent d-orbital do not form an alloy with Pt and have lower catalytic activity. In contrast, the metallic components in PtFe/Ebonex and PtCo/Ebonex form a solid solution which results in changes in the catalyst structure and surface electron state, leading to enhanced OER efficieny compared to pure Pt/Ebonex

Control as an instrument of management and institution of economic security

1. Introduction. The paper is relevant due to economic security level recession of the Russian economy in recent years. It is proposed to provide the interaction of socio-economic development indicators of the country and established control measures in the policy intended to improve the economic security of the country. It is proposed to use the institutional approach to solve the problem. 2. Methods. The main methodological basis of the paper is an institutional nature of economic relations that is expressed through an interrelated sequence of the following stages: institutions - motivation - control. In the paper, such research methods were used as the institutional approach, analysis and synthesis of historical data, the laws of dialectics, and a method of cause-effect relationships. 3. Results. This paper represents the author's recommendations for the transfer of external (negative) manifestations of control to internal (constructive) forces of cooperation. Control is disclosed as an institution necessary to provide economic security and as a condition for the effective implementation of the socio-economic strategy. The current economic security of the country is assessed on the basis of study of current macroeconomic indicators for the Russian Federation. Threats and causes of low economic security are formulated. The measures to address them are proposed. 4. Discussion. The institutional approach is known as one of the modern successful methods to describe economic relations. The problem of increasing the economic security is not solved. Increasing the effectiveness of the control measures to ensure the economic security using the institutional approach is necessary. The paper describes the theoretical and methodological basis for the study of the institutional mechanism (system of institutions) of economic security in order to increase the efficiency of monitoring the implementation of the system of institutions. A study of the properties and the nature of the institutions as recognized, purposeful and repetitive activity of economic agents aimed at the implementation and monitoring of the strategy to improve economic security is carried out. 5. Closing statement. Features of the institutional environment to provide economic security are revealed. The measures to improve the institutional chain of ensuring economic security of Russia through the effective functioning of the control system are proposed

A balanced scorecard and economic security of companies

The article describes the main methods of forming economic security of a firm using different statistical values. Particular attention is paid to the concept of a balanced scorecard, known in Russia and abroad. Economic security is analyzed as an interdisciplinary concept used at many levels of the economy. A solution to a number of management issues is offered in the context of economic security research firm. © IDOSI Publications, 2013