bluuebunny/crossref_metadata_2025_split huggingface dataset:
Activated Carbons (AC) Prepared by Direct CO2Activation of Parsea Americana seeds Biomass for Supercapacitor Electrodes
Authors: Farma Rakhmawati , Anakis Ramadani Putri , Apriyani Irma 
Published: November 2021

AbstractBiomass converted into activated carbon (AC) by using physical activation method can form micro-meso pore structure and maintain the interconnected natural pore network of biomass. AC is prepared from the biomass ofParsea Americanaseeds (PAS) through a process of pre-carbonization, chemical activation, carbonization and physical activation which is activated at temperatures of 700°C, 800°C, and 900°C. Characterization of physical properties of AC electrodes consisted of X-ray diffraction, Scanning Electron Microscope-Energy Dispersive X-ray and characterization of electrochemical properties of supercapacitor cells using Cyclic Voltametry. The results showed that the microstructure of the AC electrode has a semicrystalline structure characterized by the presence of two sloping peaks at an angle of 2θ around 24° and 44° which corresponded to the hkl (002) and (100) planes, where the lowest Lc value was produced by the PAS-900 sample. The PAS-900 sample had aggregates or lumps with smaller size in small amounts in the presence of micro-mesopores and had the highest carbon content of 94.50% with the highest capacitance value of 203.12 F/g. The temperature of 900°C is the best activation temperature in the process of manufacture AC electrodes fromParsea Americanaseeds biomass for supercapacitor cell applications.
Of ZnO Nanoparticle using Sandoricum Koetjape Peel Extract as Bio-stabilizer under Microwave Irradiation
Authors: Rini A S , Rati Y , Maisita S W 
Published: November 2021

Abstract
The use of sentul (Sandoricum koetjape) peel extract as a biostabilizer in the synthesis of zinc oxide (ZnO) nanoparticles has been carried out as an environmentally friendly production. This research was conducted by reacting a 0.2 M of Zn precursor (zinc nitrate hexahydrate) solution with Sentul peel extract (10g/l). The samples were varied based on the ratio of the volume of the Zn solution to the Sentul peel extract, i.e., 1:4, 2:3, 1:1, 3:2, and 4:1 where each sample was assigned a ZSk initial code. The ZnO synthesis used a microwave technique with a power of 360 Watt. Morphological, structural, optical absorption, and functional groups were analyzed based on the results of the characterization of SEM, XRD, UV-Vis, and FTIR Spectroscopy. SEM images show the morphology of ZnO particles in the form of semi-hollow spheres and macaron-like shapes. The particle size decreases with the addition of the volume of the Zn solution. The XRD diffraction pattern shows the diffraction peaks that correspond to the hkl plane of the wurtzite hexagonal structure of ZnO. The highest optical absorption of the UV-Vis spectrum occurred in the wavelength range of 300-360 nm. The FTIR spectrum represents the involvement of the O-H functional groups derived from the polyphenolic compound of sentul peel extract.
Modeling of Clavulanic Acid Production from Streptomyces clavuligerus using a Continuous Operation Mode
Authors: Ariza L , Rubio J , Moreno V , Niño L , Gelves G 
Published: November 2021

Abstract
Clavulanic acid is a β-lactam inhibitor produced by fermentation with Streptomyces clavuligerus cells, and it is usually used to prevent resistance to certain antibiotics. However, CA production is limited at the bioreactor level due to its low performance. The latter generates expensive processes and challenging to operate on a large scale. In this research, a mathematical model is proposed to simulate the clavulanic acid production from an operation strategy based on continuous mode. The preceding, to identify trends allowing to improve the productivity of the mentioned metabolite. Results are compared to the traditional operating batch mode. According to the results found, the final concentration of the β-lactam inhibitor could be increased by up to 60% regarding the simulated data in batch mode. Results obtained demonstrate the importance of computational techniques in bioprocess engineering since bioprocess simulation focuses on identifying critical operating parameters as a starting point in antibiotic production optimization.
Modelling of DHA Production from S. Limacinum ouc88: fed-batch perspectives
Authors: Contreras B , Basto D , Gelves G 
Published: November 2021

Abstract
Biotechnology and its need to improve industrial processes have shown the need for techniques that allow processes optimization. Computer simulation offers the advantage of determining production prospects without significant resources and experimentation time. That is why a kinetic study of DHA (docosahexaenoic acid) production from Schizochytrium limacinum OUC88 was developed in this investigation. Based on the above, a mathematical approach to simulate DHA production in a fed-batch model is proposed in this work, using Matlab software. The experimental data for determining kinetic parameters were taken from previous investigations, and a simulated DHA level in the fed-batch mode of 150 g/L was reached. On the contrary, the simulated results in batch mode present only a maximum value of 30 g/L, demonstrating the effectiveness of the fed-batch implementation with perspectives on improving processes.
Computer-Aided Evaluation of Ethanol Production from a Continuous Operating Mode using Simulink
Authors: Alvarado K , Niño L , Gelves G 
Published: November 2021

Abstract
Fossil fuels have become a great energy source worldwide. However, its prolonged use has caused severe environmental pollution problems. Biofuels generated from biomass as a product of microbial biotechnology emerge as an alternative to the use of compounds derived from oil. Therefore, their production results in complex experiments and source investment. That is why engineering studies implementation using mathematical models and simulation techniques should be specified in bioprocesses. The latter focused on optimizing the process parameters, maximizing productivity, generating greater profitability, and reducing cost. This research aimed at the computer-assisted evaluation of obtaining bioethanol from Saccharomyces cerevisiae to determine the most critical factors in the production process using a continuous mode. It was determined that the feed rate significantly influences the bioethanol volumetric productivity.
Solution of the Schrödinger torsion equation in the basis set of Mathieu functions: verification by numerical experiment
Authors: Belov A N , Turovtsev V V , Fedina Yu A , Orlov Yu D 
Published: November 2021

Abstract
The efficiency of the algorithm for the numerical solution of the Schrödinger torsion equation in the basis of Mathieu functions has been considered. The computational stability of the proposed algorithm is shown. The energies of torsion transitions determined in the basis sets of plane waves and Mathieu functions have been compared with the results of spectroscopy. A conclusion about the applicability of the algorithm using the basis set of Mathieu functions to the solution of the Schrödinger equation with a periodic potential has been derived.
Distribution of thermophysical and mechanical properties of titanium nickelide in the welding zone
Authors: Burkhovetskiy V V , Kamaev A O , Kiselev A Yu , Kurushkin D V , Khanaev V M , Khlopkov E A , Chernyavskaya N V , Shkuratov B E , Ostropiko E S , Vyunenko Yu N 
Published: November 2021

Abstract
The paper analyzes the behavior of the deformation characteristics of welded joints made of TiNi alloy with a shape memory effect. Comparison of the level of tensile strength of welded samples made by the TIG method in an Ar and He atmosphere was carried out using a Instron 5985 universal machine. The study of the material structure in the weld zone and the heat-affected zone was carried out on longitudinal sections using a JSM-6490LV electron microscope. To estimate the mechanical parameters PMT-3 microhardness tester was used. The calorimetric parameters of the welded samples were obtained using a differential scanning calorimeters METTLER TOLEDO 822e and TA Instruments Q20. To analyze the gradient properties at the weld zone and the heat-affected zone, the temperature fields were calculated using the thermal conductivity equation included in the model of the residual stress mechanism.
Symmetric 2-adic complexity of generalized cyclotomic sequences of order six with period p
n
Authors: Edemskiy V A , Koltsova S A 
Published: November 2021

Abstract
In this paper, the symmetric 2-adic complexity of generalized cyclotomic sequences of order six with period equals a power of an odd prime is studied. The estimate of symmetric 2-adic complexity of these sequences is obtained. It is shown that above sequences have high symmetric 2-adic complexity and the 2-adic complexity of this class of sequences is large enough to resist the attack of the rational approximation algorithm for feedback with carry shift registers.
Mathematical model for determining characteristic points on the radial knife of the geokhod executive body
Authors: Efremenkov A B , Aksenov V V , Sadovets V Yu , Preis E V , Pashkov D A 
Published: November 2021

Abstract
The article presents a mathematical model for determining the values of the characteristic points of the knife executive body (EB) of the geokhod. For this, the boundary conditions for determining the characteristic points on the radial knife of the geokhod executive body are indicated. The result of the work are the obtained expressions for determining: P

a.c
is the the projection of the component of the soil cutting force, depending on the cutting width, onto the main axis of rotation of the geokhod, R

e.a.c
is the projection of the component of the cutting force of the soil on the plane, which is located perpendicular to the main axis of rotation of the geokhod. Based on the work carried out, tasks for further research were identified.
Dependency of regret on accuracy of variance estimation for different versions of UCB strategy for Gaussian multi-armed bandits
Authors: Garbar S V 
Published: November 2021

Abstract
We consider two variations of upper confidence bound strategy for Gaussian two-armed bandits. Rewards for the arms are assumed to have unknown expected values and unknown variances. It is demonstrated that expected regret values for both discussed strategies are continuous functions of reward variance. A set of Monte-Carlo simulations was performed to show the nature of the relation between variance estimation and losses. It is shown that the regret grows only slightly when the estimation error is fairly large, which allows to estimate the variance during the initial steps of the control and stop this estimation later.
Thermodynamics and phase diagram calculation of the binary arsenic-tellurium system in the framework of the generalized lattice model
Authors: Gerasimov N V , Zakharov M A 
Published: November 2021

Abstract
In this work we describe how to efficiently calculate thermodynamic properties and T-x diagram of binary As-Te solution in the generalized lattice model. All the thermodynamic parameters of the As-Te solution are obtained within framework of the generalized lattice model. The binary phase diagram of As-Te system is calculated and good agreement with experimental data is obtained.
Digital technologies used in technical diagnostics, assessment of technical condition, maintenance and repair of mining machines and equipment
Authors: Gericke B L , Sushko A E , Gericke P B , Efremenkov A B 
Published: November 2021

Abstract
The article deals with the organization of a single technological space for technical diagnostics, maintenance, and repair of mining equipment. The digital technology that unites all services related to production, diagnostics of technical condition, maintenance and repair of mining equipment is based on the SAFE PLANT software package, which provides globality, scalability, versatility, integrability, modularity, distribution, and functionality. The article reflects the results of the implementation of the system at an industrial enterprise.
Mathematical description of the processes of synthesis of digital multispectral images
Authors: Kalitov M A , Kornyshev N P 
Published: November 2021

Abstract
The article discusses the features of the formation of digital multispectral images corresponding to narrow registration zones. The processes of signal transformations are analyzed during the synthesis of such images from the original multispectral images with overlapping spectral flux registration zones. Questions of the mathematical description of the differential and multiplicative method for the synthesis of spectrozonal images are discussed. Analytical expressions are given that correspond to signal transformations of the original digital multispectral images in their differential and multiplicative synthesis.
Mathematical model for determining the forces of interaction of geokhod systems with geo-environment and with each other
Authors: Khoreshok A A , Pashkov D A , Efremenkov A B 
Published: November 2021

Abstract
The article gives an example of constructing a generalized mathematical model of the interaction processes occurring in geokhod mining. An example of the solution of a particular problem is given, the determination of the values of the forces arising from the interaction of the blade of an external mover with geoenvironment.
Universal strategies for the two-alternative big data processing
Authors: Kolnogorov A V 
Published: November 2021

Abstract
We consider the two-alternative processing of big data in the framework of the two-armed bandit problem. We assume that there are two processing methods with different, fixed but a priori unknown efficiencies which are due to different reasons including those caused by legislation. Results of data processing are interpreted as random incomes. During control process, one has to determine the most efficient method and to provide its primary usage. The difficulty of the problem is caused by the fact that its solution essentially depends on distributions of one-step incomes corresponding to results of data processing. However, in case of big data we show that there are universal processing strategies for a wide class of distributions of one-step incomes. To this end, we consider Gaussian two-armed bandit which naturally arises when batch data processing is analyzed. Minimax risk and minimax strategy are searched for as Bayesian ones corresponding to the worst-case prior distribution. We present recursive integro-difference equation for computing Bayesian risk and Bayesian strategy with respect to the worst-case prior distribution and a second order partial differential equation into which integro-difference equation turns in the limiting case as the control horizon goes to infinity. We also show that, in case of big data, processing of data one-by-one is not more efficient than optimal batch data processing for some types of distributions of one-step incomes, e.g. for Bernoulli and Poissonian distributions. Numerical experiments are presented and show that proposed universal strategies provide high performance of two-alternative big data processing.
Microprocesses at the brass surface after impact of scanning beam of pulse-frequency ultraviolet nanosecond laser
Authors: Malinskiy T , Mikolutskiy S , Rogalin V , Khomich Yu , Zheleznov V , Kaplunov I , Ivanova A 
Published: November 2021

Abstract
A mode of laser heat treatment of the brass surface prior to conducting of diffusion bonding is proposed. We used the frequency-pulse radiation of a nanosecond ultraviolet laser at a pulse energy density W = 0.15 - 0.52 J/cm2. The metal sample was moved relative to a stationary laser beam along a raster trajectory (“snake”) so that adjacent spots were overlapped with an overlap ratio of ⩾ 99 %. The impact of radiation on brass was carried out in a subthreshold mode excluding crater formation. The process took place while the metal remained in a condensed state. A regular rough structure with a height of individual uplifts of the order of 1 micron was formed on the surface of the brass. article is devoted to creation of aerosolized detergent compositions, needful for use during operation of high-precision metal mirrors, as a rule, in field conditions. The created detergent compositions with inhibitory properties allow, simultaneously with carrying out the process of physicochemical cleaning of optical surface from technological impurities, to ensure its protection from the influence of adverse climatic factors during storage, transportation, installation and exploitation of the element with the possibility of its alignment. The high climatic resilience of the protective films investigated in this article, which are formed during the cleaning of the optical surface, is shown. In this case, the optical characteristics of the processed elements after climatic tests do not get worse.
Finding the fundamental solution of the bi-axially symmetric Laplace–Beltrami equation using generalized shift operator
Authors: Mavlyaviev R M , Garipov I B , Sadykova E R , Razumova O V 
Published: November 2021

Abstract
Many physical processes are described by partial differential equations. The relevance of this study is due to the need to solve applied problems of quantum mechanics, the theory of elasticity, and heat capacity. In this paper, an equation is considered that describes the field created by a contour with two axes of symmetry. The purpose of the study is to find a fundamental solution to this equation, which can later be used when solving boundary value problems.
Nonequilibrium evolution thermodynamic of poly- and two-components alloys affected by severe plastic deformation
Authors: Metlov L , Gordey M 
Published: November 2021

Abstract
The nonequilibrium evolutionary thermodynamics approach is generalized to the case of alloys prone to structural martensitic and diffusion phase transitions in them. A system of kinetic equations is written out to describe the evolution of the density of structural defects, grain boundaries, dislocations and point defects, as well as for the order parameter in the processing of these alloys by the severe plastic deformation way. The approach is illustrated by the numerical experiments results on a specific example of two-component copper-based alloys. Kinetic curves of the evolution of the grain boundaries, dislocations and atoms dissolved in a copper matrix are obtained, qualitative phase diagrams are constructed.
Bifurcation phenomenon in molecular dynamics model of coalescence/sintering on the nanoscale
Authors: Samsonov V M , Puytov V V , Talyzin I V 
Published: November 2021

Abstract
Using the isothermal molecular dynamics, coalescence/sintering of Au nanoparticles (NPs) was simulated. We have found that the solid NP sintering scenario is switched to the coalescence scenario not at the NP melting temperature T
m exactly but at a lower temperature T
0 ≈ 0.9T
m interpreted as the critical temperature corresponding to a coalescence/sintering bifurcation phenomenon: in the temperature range from T
0 – 2 K to T
0 + 2 K to the resulting (daughter) NPs of the same size can have either liquid-like or crystalline structure after coalescence/sintering at the same fixed temperature.
Mirror descent algorithm on the indefinite control horizon
Authors: Shiyan D N , Kolnogorov A V 
Published: November 2021

Abstract
We consider the problem of optimal control in a random environment in a minimax setting as applied to data processing. It is assumed that the random environment provides two methods of data processing, the effectiveness of which is not known in advance. The goal of the control in this case is to find the optimal strategy for the application of processing methods and to minimize losses. To solve this problem, the mirror descent algorithm is used, including its modifications for batch processing. The use of algorithms for batch processing allows us to get a significant gain in speed due to the parallel processing of batches. In the classical statement, the search for the optimal strategy is considered on a fixed control horizon but this article considers an indefinite control horizon. With an indefinite horizon, the control algorithm cannot use information about the value of the horizon when searching for an optimal strategy. Using numerical modeling, the operation of the mirror descent algorithm and its modifications on an indefinite control horizon is studied and obtained results are presented.
Polynomials, numerical triangles and sequences associated with the probability distribution of the hyperbolic cosine type for odd values of the parameter
Authors: Tokmachev M S 
Published: November 2021

Abstract
The article introduces a new class of polynomials that first appeared in the probability distribution density function of the hyperbolic cosine type. With an integer change in one of the parameters of this distribution, polynomials in the form of a product of positive factors are written out with an increasing degree. Earlier, the author found a connection between the distribution of the hyperbolic cosine type and numerical sets, in particular, in the simplest cases with the triangle of coefficients of Bessel polynomials, the triangle of Stirling numbers, sequences of coefficients in the expansion of various functions, etc. Also from the distribution formed numerous numerical sequences, both new and widely known. Consideration of polynomials separately from the density function made it possible to reconstruct numerical sets of coefficients, ordered in the form of numerical triangles and numerical sequences. The connections between the elements of the sets are established. Among the sequences obtained, in the simplest cases, there are those known from others, for example, physical problems. However, the overwhelming majority of the found number sets have not been encountered earlier in the literature. The obvious applications of this research are number theory and algebra. And the interdisciplinarity of the results indicates the possibility of applications and enhances their practical significance in other areas of knowledge.
Study of succinic anhydride amidation by 2-aminothiazol
Authors: Tyurina T G , Kryuk T V , Kudryavtseva T A , Semenova R G , Romanenko N A , Volkova G K 
Published: November 2021

Abstract
The reaction between succinic anhydride and 2-aminothiazole was carried out in polar organic solvents (acetone, 1,4-dioxane, isopropanol) and in a mechanochemical reactor. By of X-ray phase analysis, IR, 1H, 13C NMR spectroscopy it was found that in both techniques of carrying out the reaction, the only product was succinamide. It was shown that the process efficiency in the mechanochemical reaction conditions is higher in comparison with the traditional solution’s synthesis. The solid-phase interaction development was proceeded during 45 days after load removed, it was especially intense in the first 10 days.
Application of super cells for quantum-mechanical calculations of the mixing enthalpy of the BCC-phase of the Fe-V system for the basic state
Authors: Udovsky A L , Kupavtsev M V 
Published: November 2021

Abstract
In this work, the super-cells were used for quantum mechanical calculations of the mixing enthalpia of the BCC phase of the Fe-V system for the ground state. The values of total energy were calculated using 16 -th and 54- atomic super-cells for both clean components and alloys. The mixing enthalpy (ΔH) for the BCC phase was calculated on four 16- and 54- atomic super-cells in the vicinity of pure components, on the basis of which the dependence of the concentration ΔH for BCC alloys in the ferromagnetic state of the Fe-V system of the ground state was built.