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Increasing the productivity of the arc surfacing process with a ribbon electrode can be achieved by increasing the width of the electrode. However, as the width of the electrode increases, the likelihood of weld defects forming is increased. This is due to the dispersion of the thermal influence of the arc on the base metal; increasing the size of the weld pool; the occurrence of a magnetic blast effect, because of which the displacement of weld pool liquid metal is possible; the appearance of cuts, irregularities of the edges of the deposited metal. By taking control over the movement of the welding arc at the end of the ribbon electrode, thereby stabilizing the melting of the base metal, it is possible to use the magnetic control of the arc movement at the end of the electrode and eliminate the effect of «magnetic blast». In the presented article, the possibility of controlling the process of moving the arc along the end of the tape electrode due to its interaction with the induced magnetic field is considered. Two ways of controlling the surfacing process are proposed – one for case of using profiled ribbon electrode tape and the other – for case of using flat (non-profiled) ribbon electrode. The possibility of controlling the regularity of the process of moving the arc along the end of the electrode depending on the conditions of heat input of the arc energy into the electrode and the base metal and the weld pool is shown. This will allow to use ribbon electrodes with increased width, thus improving deposition process efficiency. Schemes of the process of magnetic control of arc movement along the end of the tape electrode due to the action of a magnetic field are presented, Рассмотрена возможность регламентированного управления процессом перемещения дуги по торцу ленточного электрода за счет ее взаимодействия с наведенным магнитным полем. Предложены два пути управления процессом наплавки – с применением профилированной электродной ленты и плоской (непрофилированной). Показана возможность управления закономерностью процесса перемещения дуги по торцу электрода в зависимости от условий тепловложения энергии дуги в электрод и основной металл и сварочную ванну. Приведены схемы процесса магнитного управления перемещением дуги по торцу ленточного электрода за счет действия магнитного поля, Розглянуто можливість регламентованого керування процесом переміщення дуги по торцю стрічкового електрода за рахунок її взаємодії з наведеним магнітним полем. Запропоновано два шляхи керування процесом наплавлення – із застосуванням профільованої електродної стрічки і плоскої (непрофільованої). Показано можливість управління закономірністю процесу переміщення дуги по торцю електрода в залежності від умов тепловкладення енергії дуги в електрод і основний метал та зварювальну ванну. Наведено схеми процесу магнітного управління переміщенням дуги по торцю стрічкового електрода за рахунок дії магнітного поля

The process $e^+e^-{\to}K^+K^-��$ has been studied in the center-of-mass energy range from 1.59 to 2.007\,GeV using the data sample of 59.5 pb$^{-1}$, collected with the CMD-3 detector at the VEPP-2000 $e^+e^-$ collider in 2011, 2012 and 2017. The $K^+K^-��$ final state is found to be dominated by the contribution of the $��(1020)��$ intermediate state. The cross section of the process $e^+e^-{\to}��(1020)��$ has been measured with a systematic uncertainty of 5.1$\%$ on the base of 3009 $\pm$ 67 selected events. The obtained cross section has been used to calculate the contribution to the anomalous magnetic moment of the muon: $a_��^{����}(E

Целью данной работы является проведение исследований в области синтеза керамических материалов технического назначения на основе системы FeO-Al[2]O[3]-SiO[2], которая позволит выровнять недостатки традиционной кордиеритовой керамики.

Lactoferrin is a non-heme iron-binding glycoprotein with multiple health-beneficial functions including antimicrobial, antioxidant, anticarcinogenic, and immunomodulatory effects. There is emerging evidence that neutrophils may serve as targets of lactoferrin in vivo, and here we show how recombinant human lactoferrin (rhLf) can contribute to this regulation. Indeed, our results demonstrate that rhLf binds efficiently to human neutrophils and induces a variety of early cellular responses such as mobilization of intracellular Ca2+, remodeling of actin cytoskeleton, and degranulation (release of lysozyme and myeloperoxidase). In addition, rhLf facilitates lectin-induced H2O2 production and stabilization of lectin-induced cellular aggregates. The role of calcium signaling seems to be essential for rhLf-induced activation of neutrophils, as Ca2+-chelators inhibit degranulation response while lectin-induced H2O2 production correlates significantly with cytoplasmic Ca2+ elevation. Taken together, our findings justify that rhLf can activate neutrophil functions in a calcium-dependent manner and hence, can potentiate innate immune responses.

The electrodynamic model of a horizontally homogeneous surface layer with allowance for singly charged aerosol particles in the atmosphere is considered. The mathematical model includes the following equations: ionization-recombination transport equations due to the electric field and turbulent diffusion of polar light ions (aeroions), including terms describing their interaction with aerosol particles, the equations of transport of the formed heavy ions, and the stationary Poisson equation with allowance for light and heavy ions. The equilibrium conditions for heavy ions are assumed to be satisfied. The representation for the coefficients of turbulent diffusion (for light and heavy ions) coincide, which corresponds to a neutral stratification of the surface atmosphere. Analysis of the equations shows that the characteristic spatial scales of distributions for light and heavy ions at concentrations of aerosol particles of the order of 1010 m-3 are due to the transfer by an electric field of not more than one meter, and due to turbulent diffusion - several meters, and the time for establishing a stationary state is 80 s. The results of numerical simulation of the structure of the turbulent electrode layer are presented. The distributions of electrical characteristics of the surface layer are obtained depending on the values of the concentration of aerosol particles in the atmosphere and the degree of turbulent mixing. The electric space charge created by light and heavy ions is positive. The maximum value of the density of space charge is reached near the surface of the earth and then decreases with height.

The article describes an electrodynamic model of the horizontally homogeneous turbulent surface atmosphere in the presence of monodisperse aerosol particles. The mathematical model includes nonstationary ionization-recombination transport equations due to the electric field and turbulent diffusion of polar light ions (air ions), in-cluding terms describing their interaction with aerosol particles and also the stationary Poisson equation with al-lowance for the formed heavy ions. It is assumed that the equilibrium condition for heavy ions is satisfied, and their transfer is not taken into account. Analysis of the system of equations makes it possible to estimate the time of estab-lishment of a stationary electrodynamic state, which varies from 100 to several tens of seconds with an increase in the concentrations of aerosol particles in the atmosphere from 5·109 to 5·1010 m-3. The characteristic height of the elec-trode layer varies from several tens of centimeters to several meters: it increases with increasing degree of turbulent mixing and decreases with increasing concentration of aerosol particles. To obtain stationary analytical solutions of the model equations, the following assumptions are made: the rate of ionization in the surface atmosphere is assumed to be constant; at the considered concentrations of aerosol particles, recombination of light ions can be neglected; the electric field and the coefficients of turbulent diffusion (for light and heavy ions) are constant and do not depend on altitude. Approximate analytical expressions are obtained for the vertical distribution of the concentrations of polar aero ions and the density of the space electric charge as a function of the concentration of aerosol particles, the electric field strength, and the degree of turbulent mixing. The obtained results are in good agreement with the theory of the electrode effect in the atmosphere and can be the basis for constructing a numerical model of electrodynamic processes in the surface layer.

Scheelite-like oxides of the ABO4 type can be used as materials for lasers, phosphors, etc [1]. We studied the optical properties of CaMoO4:Bi ceramics, the role of the Bi dopant in the formation of the energy structure. Adding Bi affects energy structure of СаMoO4 by changing it is energy gap and leading to non-elementary luminescence quenching. Работа профинансирована Министерством Образования и Науки Российской Федерации (Правительственное задание №3.1485.2017/4.6).

Статья посвящена проблемам выявления и оценки факторов, инициирующих территориальные перемещения населения и служащих для обоснования текущих целей регулирования миграции трудовых ресурсов. The article is devoted to the problems of identification and estimation of the factors that trigger population movement and serve to justify the current regulatory objectives.

Benzene is one of the important raw materials for organic synthesis. Extraction and extractive distillation (ED) are used to recover benzene from petroleum and coking coal products. Application of the systems with partially thermally coupled distillation columns (PTCDC) is one of the effective ways to reduce the energy consumption of ED. In this paper, evaluation is considered of the energy efficiency of ED schemes with PTCDC (PTCEDS) to separate benzene (B)-cyclohexane (CH)-toluene (T) mixture with two different initial feed compositions and N-methylpyrrolidone (NMP) as entrainer. The mixture #1 is some equivalent of the product of catalytic dealkylation of the gasoline fraction of hydrocracking with B, CH, T concentrations 40, 20, 40 mass %, respectively, and mixture #2 is a some equivalent of product of the hydrocracking and hydropurification of vapor cracking gasoline with B, CH, T concentrations 50, 5, 45 mass %, respectively. Three conventional ED schemes and five ED schemes with PTCDC were considered. All 8 schemes were compared by the total boiler heat duties criterion under optimal values of operating parameters. Optimization was carried out by using sensitivity analysis and the SQP (sequential quadratic programming) optimization tools of Aspen Plus. It was determined that the scheme where toluene is separated in the first column as the bottom product had the lowest energy consumption among the conventional schemes in all cases of the initial feed compositions. The best solution with PTCDC in the both cases is the scheme where CH is recovered in the first ED column as a distillate, B is a distillate of the main column and T is a bottom product of the complex column side stripper section. The power consumption reduces by 19.8% and 22% for mixture #1 and mixture #2, respectively, compared to the conventional ED schemes with two outlets columns, The work was supported by the Russian Foundation for Basic Research, project No. 17-03-00347