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The formation of graphene on the surface of a Gd film on a highly oriented pyrolytic graphite substrate has been studied by photoelectron spectroscopy using synchrotron radiation. It has been demonstrated that the formation of graphene passes through the phase of gadolinium carbidization, which is transformed with increasing annealing temperature. It has been established that, at a temperature of 1300 K, gadolinium carbide with the Gd2C3 stoichiometry is transformed into the carbide with the GdC2 stoichiometry. The analysis of all transient phase processes has been performed on the basis of the fine structure of photoelectron lines and dispersion of electron states. It has been shown that the Dirac cone of electron states of graphene is retained.

Sharpening of the curvilinear cutting edges at the rear surface of helical bits is considered. A mathematic model of the rear surfaces takes account of the bit parameters and the distribution of the rear angles along the cutting edge. The position of the grinding wheel in sharpening is determined.

Embedding foreign atoms or molecules in graphene has become the key approach in its functionalization and is intensively used for tuning its structural and electronic properties. Here, we present an efficient method based on chemical vapor deposition for large scale growth of boron-doped graphene (B-graphene) on Ni(111) and Co(0001) substrates using carborane molecules as the precursor. It is shown that up to 19 at. % of boron can be embedded in the graphene matrix and that a planar C–B sp2 network is formed. It is resistant to air exposure and widely retains the electronic structure of graphene on metals. The large-scale and local structure of this material has been explored depending on boron content and substrate. By resolving individual impurities with scanning tunneling microscopy we have demonstrated the possibility for preferential substitution of carbon with boron in one of the graphene sublattices (unbalanced sublattice doping) at low doping level on the Ni(111) substrate. At high boron content the honeycomb lattice of B-graphene is strongly distorted, and therefore, it demonstrates no unballanced sublattice doping., The authors acknowledge Saint Petersburg State University for Research Grants 11.37.634.2013 and 11.50.202.2015, RFBR (Grant No. 14-02-31150), and BMBF (Grant No. 05K12OD3). We acknowledge Helmholtz Zentrum Berlin für Materialien und Energie for support within bilateral Russian German Laboratory program. MMO and EVC acknowledge the Tomsk State University Academic D.I. Mendeleev Fund Program (Research Grant No. 8.1.05.2015).

A new approach to determining the cutting properties of a diamond tool with a single-layer diamond–galvanic coating is proposed. The method is based on determining the concentration of diamond grains in the working layer of the tool.

The machining of complex parts with surface shaping by different sections of the cutting edge is considered.

Two-and three-dimensional topological insulators are the key materials for the future nanoelectronic and spintronic devices and quantum computers. By means of angle-and spin-resolved photoemission spectroscopy we study the electronic and spin structure of the Bi-bilayer/3D topological insulator in quantum tunneling regime formed under the short annealing of BiTeSe Owing to the temperature-induced restructuring of the topological insulator's surface quintuple layers, the hole-like spin-split Bi-bilayer bands and the parabolic electronic-like state are observed instead of the Dirac cone. Scanning Tunneling Microscopy and X-ray Photoemission Spectroscopy measurements reveal the appearance of the Bi terraces at the surface under the annealing. The experimental results are supported by density functional theory calculations, predicting the spin-polarized Bi-bilayer bands interacting with the quintuple-layers-derived states. Such an easily formed heterostructure promises exciting applications in spin transport devices and low-energy electronics., The work was partially supported by grant of Saint Petersburg State University for scientific investigations (No 15.61.202.2015). We acknowledge the financial support of the University of Basque Country UPV/EHU (Grant No. GIC07-IT-756-13), the Departamento de Educación del Gobierno Vasco and the Spanish Ministerio de Ciencia e Innovación (Grant No. FIS2010-19609-C02-01), the Spanish Ministry of Economy and Competitiveness MINECO (Grant No. FIS2013-48286-C2-1-P) and the Tomsk State University Competitiveness Improvement Program.

The geometry of the curvilinear cutting edge of a helical bit such that the life is uniform over its length is considered, on the basis of a mathematical model.

Methods of shaping the blank in cutting are considered and classified. Their advantages and disadvantages are outlined, and their use is illustrated.

Switching of the resistance in thin ferroelectric films is a complex phenomenon involving an influence of polarization states, point defects, processes of electron injection from electrodes and peculiarity of polarization charges screening. In order to clarify the mechanism of surface charge screening under ferroelectric polarization switching and its correlation with the local resistive properties in thin ferroelectric films, we studied the changes in the surface potential under dc bias voltage application in SrTiO3/La0.7Sr0.3MnO3/BaTiO3 heterostructures using different modes of atomic force microscopy (Kelvin probe, piezoresponse, and conductive) at ambient conditions. It is found that the peculiarity of surface charge screening under polarization reversal gives a strong electrostatic contribution in the measurements of local resistive properties at the ambient conditions and could completely veil the real current distribution over the film surface. Remarkably, scanning tunnelling microscopy measurements under ultra-high vacuum conditions show evidence of oxygen vacancy formation in thin ferroelectric films after poling, revealing an increase of the film thickness due to the chemical expansion.

Background The aim was to estimate the prevalence of harmful alcohol use in relation to socio-demographic characteristics among acutely ill medical patients, and examine identification measures of alcohol use, including the alcohol biomarker phosphatidylethanol 16:0/18:1 (PEth). Methods A cross-sectional study, lasting one year at one hospital in Oslo, Norway and one in Moscow, Russia recruiting acute medically ill patients (≥ 18 years), able to give informed consent. Self-reported data on socio-demographics, mental distress (Symptom Check List-5), alcohol use (Alcohol Use Disorder Identification Test-4 (AUDIT-4) and alcohol consumption past 24 h were collected. PEth and alcohol concentration were measured in whole blood. Results Of 5883 participating patients, 19.2% in Moscow and 21.1% in Oslo were harmful alcohol users, measured by AUDIT-4, while the prevalence of PEth-positive patients was lower: 11.4% in Oslo, 14.3% in Moscow. Men in Moscow were more likely to be harmful users by AUDIT-4 and PEth compared to men in Oslo, except of those being ≥ 71 years. Women in Oslo were more likely to be harmful users compared to those in Moscow by AUDIT-4, but not by PEth for those aged Conclusions The prevalence of harmful alcohol use was high at both study sites. The prevalence of harmful alcohol use was lower when assessed by PEth compared to AUDIT-4. Thus, self-reporting was the most sensitive measure in revealing harmful alcohol use among all groups except for women in Moscow. Hence, screening and identification with objective biomarkers and self-reporting might be a method for early intervention.

This article presents the analysis of the influence of cutting speed and the thickness of a cut layer on stability of a cutting land. Based on the analysis there is considered the design of the cutting part of a spiral drill bit with more uniform distribution of stability of cutting points, compared to a usual drill bit. The authors established the equation describing the projection of a cutting land onto a plane perpendicular to the axis of the drill bit.

The authors give an approval of military personnel biosphere research, which is necessary for prevention and early detection of substance misuse among military personnel of the Armed Forces. The article provides documents, regulating procedure of the chemico-toxicological analysis of a biological material, and staging of early detection of substance misuse among conscripts and professional soldiers. The authors gave information about main current problems of this activity, revealed its disadvantages and detected prevention measures.

The specific features of the electronic and spin structures of a triple topological insulator Bi2Te2.4Se0.6, which is characterized by high-efficiency thermoelectric properties, have been studied with the use of angular- and spin-resolved photoelectron spectroscopy and compared with theoretical calculations in the framework of the density functional theory. It has been shown that the Fermi level for Bi2Te2.4Se0.6 falls outside the band gap and traverses the topological surface state (the Dirac cone). Theoretical calculations of the electronic structure of the surface have demonstrated that the character of distribution of Se atoms on the Te–Se sublattice practically does not influence the dispersion of the surface topological electronic state. The spin structure of this state is characterized by helical spin polarization. Analysis of the Bi2Te2.4Se0.6 surface by scanning tunnel microscopy has revealed atomic smoothness of the surface of a sample cleaved in an ultrahigh vacuum, with a lattice constant of ~4.23 Å. Stability of the Dirac cone of the Bi2Te2.4Se0.6 compound to deposition of a Pt monolayer on the surface is shown., This study was supported by the Ministry of Education and Science of the Russian Federation, the St. Petersburg State University (project nos. 11.38.271.2014 and 15.61.202.2015), and the Russian Foundation for Basic Research (project nos. 12-02-00226, 13-02-91327, 14-08-31110, and 13-02-12110). The research was also performed at the Resource Center “Physical Methods of Surface Investigation” at St. Petersburg State University. We are also grateful to collaborators of the Helmholtz-Zentrum (Berlin) for financial and technical support.

The paper describes a method of processing of helical end mills shaped surfaces of straight profile. The authors describe the possibility of processing the contoured surface of the helical cutter with a given profile by means of mathematical and computer modeling.

In this paper, we report the results of experimental study of electron transport mechanisms in ferroelectric BaTiO3 ultrathin epitaxial films in a broad temperature range. For this purpose ferroelectric tunnel junctions based on STO/LSMO/BTO/Au structures were fabricated with different thicknesses of ferroelectric films (from 3 to 12 nm). Ferroelectric and electrical properties of heterostructures were measured at temperatures ranging from 40 K to 300 K. Based on experimental results, we find that prevailing transport mechanisms in BaTiO3 epitaxial thin film is determined by the film thickness. Below the certain thickness of the BaTiO3 film, a dominant contribution in the current through the structure is due to elastic tunneling. Increasing the thickness of the ferroelectric film leads to an impact from inelastic tunneling, mainly due to an interaction with traps caused by cation and anion vacancies in oxide sub-lattices. We suppose that the specificity of transport mechanisms in BaTiO3 ultrathin films is defined by the ratio of film thickness and the mean free path of injected electrons, along with repolarization processes synchronized with the ferroelectric coercive field. The latter point has been confirmed by the results of experimental study in a broad temperature range.

The article is dedicated to the 20th anniversary of the Federal government health resort institution of the Federal Drug Control Service of the Russian Federation (FGI "Health resort "Podmoskovie" of the Federal Drug Control Service of the Russian Federation). In this health resort were developed treatment programs for patients with abnormalities of the cardiovascular, respiratory and digestive systems; methods of ultrasonic, laser and magnetic therapy, atmospheric hypoxic, herbal medicine, speleotherapy are employed. Widely used natural healing factors of Ruza district of the Moscow region such as climate therapy, treatment with mineral water group of X type of Smolensk from own wells and balneo-mudtherapy. Over the past 20 years 70 000 patients received an appropriate treatment in this health resort.

The confirmation of the fact of alcohol abuse is currently an important problem of both medical and social significance. Of all biological markers of alcohol consumption presently in use, blood phosphatidylethanol (PEth) is considered to be most sensitive and specific one. Therefore it has promising prospects for the further application. There is no universally accepted method for the calculation of the phosphatidylethanol concentration in human blood. For this reason, the present article places emphasis on the comparative characteristic of various methods for the determination of this substance.Подтверждение факта злоупотребления алкоголем в настоящее время является важной задачей, имеющей как медицинское, так и социальное значение. Из всех биомаркеров употребления алкоголя, по данным литературы, максимальной специфичностью и высокой чувствительностью обладает фосфатидилэтанол (PEth), определение которого на сегодняшний день является наиболее перспективным. Единой методики расчета содержания PEth в крови человека не существует, поэтому данная статья посвящена сравнительному анализу различных методик определения PEth.

The selection of the particular computer system or programming language plays a great practical role (in terms of the convenience of the interface, the speed of implementation, and information transfer with the exterior), but the final outcome—the quality of the cutting tool, its rational selection, and its operational efficiency—depends primarily on the mathematical model. Notwithstanding the diversity of the mathematical models, two large groups may be identified: optimization models and simulation models [1, 5]. Correspondingly, two types of computer models may be distinguished. We now consider the content of some computer models of the two types used in the design and operation of cutting tools in various branches of industry.

This study has demonstrated the possibility of using immunochromatographic test strips for the reliable qualitative detection of amphetamine and methamphetamine in the urine samples at a cut-off level of 300 ng/ml. The test strips obtained from different manufactures are shown to be slightly different in terms of specificity as appears from the frequency of cross-reactions with various pharmaceutical products and narcotic drugs. Also, the use of the immunochromatographic strips makes it possible to determine amphetamine in a range of concentrations from 100 to 1000 ng/ml by measuring the intensity of test-line colour with the help of a TotalLab TL120 programmer and special scanning programs. The analysis for amphetamine using the NrcoStop (Osiris S) immunochromatographic strips failed to confirm the presence of this substance in the urine samples from the subjects who had drunk 0.5 l of energy drinks, such as Adrenaline RUSH, Red Bull, and Burn. It means that the presence of amphetamine in the urine should not be attributed to the consumption of such drinks.

Recombinant human proinsulin - protein A domain fusion protein (rPFP) was immobilized on synthetic matrix, resulting in inexpensive immunoglobulin-binding sorbent. This is an alternate to a protein A affinity support. A Standard technique was used for immobilization. Experiments, optimizing in ligand concentration, were performed.

With the discovery and first characterization of graphene, its potential for spintronic applications was recognized immediately. Since then, an active field of research has developed trying to overcome the practical hurdles. One of the most severe challenges is to find appropriate interfaces between graphene and ferromagnetic layers, which are granting efficient injection of spin-polarized electrons. Here, we show that graphene grown under appropriate conditions on Co(0001) demonstrates perfect structural properties and simultaneously exhibits highly spin-polarized charge carriers. The latter was conclusively proven by observation of a single-spin Dirac cone near the Fermi level. This was accomplished experimentally using spin- and angle-resolved photoelectron spectroscopy, and theoretically with density functional calculations. Our results demonstrate that the graphene/Co(0001) system represents an interesting candidate for applications in devices using the spin degree of freedom., The authors acknowledge Saint-Petersburg State University for a research Grants 11.37.634.2013 and 11.50.202.2015, RFBR (Grant 14-02-31150), and BMBF (Grant 05K12OD3). A.G. acknowledges support from the ERC Grant Super2D. M.M.O. and E.V.C acknowledge the financial support of the University of Basque Country UPV/EHU (Grant GIC07-IT-756-13) as well as of the Departamento de Educacion del Gobierno Vasco and the Spanish Ministerio de Ciencia e Innovacion (Grant FIS2010-19609-C02-01).