bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors Influencing Internal Audit Fund Sufficiency
Authors: Al Fayi Salem
Published: March 2021

This study is motivated by the lack of internal audit (IA) fund research and examines the influence that the following elements have on IA fund sufficiency: IA quality factors (experience, certification and training), the independence and objectivity of Chief Audit Executives (rotation, reporting line and appointment), IA characteristics (IA department size and age), budget changes, and IA risk assessment activities. This study identifies 2,205 Chief Audit Executives and uses logistic regression to examine the impact of internal audit quality, independence, characteristics and activity on IA fund sufficiency. The results show that IA quality variables, independence and objectivity variables, IA size, age and budget changes all contribute to predicting fund sufficiency for the model IA department. The results also demonstrate that the risk assessment variable does not contribute to the model. The value of this study is that it provides empirical evidence regarding identifying factors that influence internal audit fund sufficiency. This study’s evidence has implications for policymakers and practitioners, as the actual issue of IA fund sufficiency has yet to be examined.
Problems of dynamic modeling of the commissioning of residential buildings in the post-Soviet countries
Authors:   Synergy University, Ledneva Olga V. , Tsypin Alexander P. ,   Synergy University
Published: March 2021

The article is devoted to the description of procedures of economic and mathematical modeling of trends in the field of housing construction taking into account the peculiarities of various countries of the post-Soviet space. The results of analysis of well-known scientific publications on forecasting the dynamics of housing market indicators are presented. It has been shown that most domestic and foreign scientists as the most effective methods of modeling these indicators consider methods of analyzing time trends, in which polynomials of high (in some cases up to the fourth degree) order are used to approximate the available retrospective data. Other common approaches to solving this problem are the use of short-term forecasting based on moving average algorithms, as well as the use of the SARIMA model, which takes into account the trend and seasonal wave. The article shows that these methods do not fully take into account the profound changes in the construction complexes of the post-Soviet states caused by the significant structural transformation of their socio-economic systems. The authors proposed to use econometric models based on regressions with dummy variables to model the main indicators of housing construction, taking into account the complex structure of the external and internal environment of national construction complexes. It has been shown that in a significant number of practical situations, a fairly simple but effective way to take into account the components of the time series of the indicators under consideration in one complex model is to use the model of "change in growth (fall)" when choosing the time of the beginning (end) of a crisis situation as a characteristic point. The results of modeling the main indicators of housing construction for various countries of the post-Soviet space showed that the proposed model when constructing the medium-term forecast allows taking into account the situation component of the analyzed time series.
Approximation of life expectancy in Russia based at interval data and minimax model
Authors:   National Research Saratov State University named aft N. G. Chernyshevsky, faculty of Mechanics and Mathematics, Vygodchikova Irina Yu.
Published: March 2021

Article provides automated processing of interval data on dynamics life expectancy in Russians over a long period of time (more than 100 years). Software product for approximation of dynamic processes in the demographic sphere that occur under unstable trend conditions is developed. Software product is based at the author's model of spline approximation the interval data by linear polynomials. The algorithm of program uses method for finding the moments of joining linear splines using reasonable properties of solving minimax problem for dynamic series whose values are interval data: the lower limit of the interval is fixed life expectancy of men, the upper limit is fixed life expectancy of women. As result of computational experiments, the jump-type curve approximation obtained. The jump-type curve preserves important properties of modeled series and has good approximation properties. The special feature of developed software product is the ability to get an approximating function in a matter of seconds, which has high accuracy and allows you to analyze profile of demographic situation in Russia, taking into account life expectancy of men and women over a long period. Were identified key turning points (mid 20th century and beginning of 21st century, when there was decline in life expectancy of men and his essential distance from a more stable indicator for women), after which dynamics of indicators have shown an increasing trend of both indices and reducing the gap between them.
Prevalence of Malaria among Febrile Patients attending Government Hospitals in Ondo State, South-West Nigeria
Authors: F.O Omoya , KO Ajayi
Published: March 2021

Background: The use of malaria infection prevalence among febrile patients is a valuable epidemiological surveillance tool. In this study, a cross sectional study was conducted among febrile patients in selected government Hospitals in Ondo State for malaria prevalence. Results: Plasmodium falciparum is the only encountered malaria parasite with prevalence values of 82.72% (426/515) and 80.19% (413/515) were obtained for microscopy and RDTs respectively. The prevalence of malaria among the males (86.59%) was higher than the females (80.65%), all age groups in this study were vulnerable with highest infection rate of 89.66% among age group 11-20 years. The parasites densities ranged between 209 and 22310 parasites/μl with a mean parasitaemia of 5522.17 ± 183.30 parasites/μl. The prevalence of malaria among the febrile participants that have taken antimalarial drug before visiting the hospital is 82.94% (389/469) with the mean parasitaemia of 4615.21 ± 188.14 parasites/μl while among the participants that have taken herbs before visiting the hospital the prevalence is 85.03% (142/167) with the mean parasitaemia of 4913.81 ± 330.20 parasites/μl. Conclusion: There was high prevalence of malaria among febrile patients and this fi nding will help improve the diagnosis and treatment of other febrile (non-malaria) infections, limit antimalarial usage to only malaria parasite-based test true positives and serve as a guide to combat malaria drug resistance in the study area.
Prevalence and Levels of Forward Head Posture among School Going Children
Authors: Chandoliya Hemendra , Chorsiya Varsha , Kaushik Dhananjay
Published: March 2021

Introduction: Exposure of overloaded bag packs and early usage of digital gadgets amongst school going children alters the cervical spine posture. The present research work intends to study the prevalence of forward head posture in school going children. The study also elucidates the ranges to consider for mild, moderate and severe forward head posture prevalence. Methods: A total of 100 school students (50 males and 50 females) were recruited for cross-sectional study. Assessment of forward head posture was done using plumb line. The students were made to stand at a point marked 25 cm distance away from the plumb line. The researcher, from the side view, using a meter scale, measured the distance between the tragus of the ear and plumb line and record it. The weight of the school bag was measured using the weighing machine and the time for which gadgets were used was recorded as per the subject/parents feedback. Results: The mean values for age, height, weight and BMI are 13.67 ± 0.55 years, 158.56 ± 7.71 cms, 46.47 ± 10.50 kgs and 18.40 ± 3.48 kg /m2 respectively. The mean values for gadgets time use, distance plumb line and weight bag are 130.50 ± 67.07 min, 1.96 ± 1.19 cm and 4.32 ± 1.70 kgs respectively. About ~27% children having mild or no FHP (less than or equal to 1 cm), ~37% children having moderate FHP (ranging between 1.01 cm to 2.49 cm) and ~36% children found to have severe FHP (more than or equal to 2.5 cm). Conclusion: The study showed that the FHP is developing at early stage in the school going children and it has the potential of altering cervical spine biomechanics. Early screening is much essential aspect to prevent FHP. The ergonomic based awareness programs should be organized to sensitize children about the right posture and to indulge them in physical activity.
Thresholds of Body and Mind
Authors: Hague A
Published: March 2021

What are the limits? How much can we endure? What will be tolerated. When does anguish start? These limits are the thresholds beyond which suffering starts. They have a direct effect on the immune system which interacts between the body and the mind. It is our built-in, automatic doctor.
How to Get Ill, Stay Ill and Die
Authors: Hague A
Published: March 2021

This is your death plan. Choose the easy options. Go with the flow. Do what you want to do. This will get you off the endless conveyor. No more effort and it’s all downhill. Be advised by advertisers, doctors who know nothing about food or exercise, a government that wants to squeeze you and business intent on profit. If you are reading this thinking you can do the opposite, think again. You will be fighting powers you did not know exist. Perhaps you should be in a cave without money, friends or help. Survival in a civilised society is difficult. Only the brave can go against the grain. There are three sectors: food, exercise and lifestyle. All three are waiting for you like monsters of the deep to suck you in and kill you. You think you are being looked after. Beware!
Lifestyle, Nutritional and Psychological Changes in Adult Patients with Inborn Errors of Metabolism during COVID 19 Pandemic: Results from an Online Survey
Authors: Gugelmo G , Schiff S , Lovato E , Lenzini L , Boscari F , Francini-Pesenti F , Avogaro A , Vitturi N
Published: March 2021

When COVID-19 pandemic out broke in Italy, during the lockdown from March to May 2020, Inborn Errors of Metabolism (IEM) patients were at risk of not getting their dietary special products and routine visits. Moreover, during pandemic, psychological difficulties might have arose in these subjects, even more severe than in the general population due to the worries about acute decompensation caused by a possible COVID-19. In order to evaluate the patients’ perception of the outbreak situation and their related needs, three simple online anonymous surveys drawn up by Google Forms were sent to patients and families referring to our Adult IEM Center. Answers were collected between April and May 2020. Questionnaires investigated nutritional and lifestyle changes and psychological status using validated psychological tools. 19 patients with IEM filled out our survey (Median age 26-30 years). The most common nutritional therapy was low protein diet. During quarantine 12% patients failed to follow their usual medical diet, 65% reduced their physical activity and no one underwent an acute metabolic crisis. 57% of patients asked for more frequent access to the reference center. 33% of patients showed stress perceived of clinical relevance and general health perception were out of normal in 40% of patients. In conclusion, during quarantine some patients reported difficulty in following their medical diet or physical activity and were clinically stressed. Despite this, no one experienced a metabolic crisis, but asked for contacting the Metabolic Team in different ways than usual due to worries about their health condition. Telemedicine, the possibility of clinical follow-up at home patient (Including blood tests) and reservation of non-COVID-19 beds for hospital admission of IEM patients may have contributed to help IEM adult patients in better face this emergency time.
Synthesis of monomers for the preparation of optically active poly(amide–imide)s. Part 1. Synthesis of chiral aminocarboxylic acids containing an imide cycle and a fragment of the natural amino acid
Authors:   Yaroslavl State Technical University, Koverda Anna A. , Betnev Alexander F. ,   Yaroslavl State Technical University, Kofanov Evgeny R. ,   Yaroslavl State Technical University
Published: March 2021

In a previous work, it was shown that the imidization reaction of dystereomerically pure nitrophenylcycloalkanedicarboxylic acids with natural amino acids in acetic acid proceeds with partial racemization of the α-carbon center of the amino acid fragment. Carrying out the synthesis in DMF at room temperature allows to obtain imides with preservation of the configuration of all chiral centers. New aminocarboxylic acids were synthesized based on them, which are the starting compounds for the monomers of optically active PAI. We used various reduction systems to produce aromatic amine compounds containing an imide cycle, such as tin or tin(II) chloride and hydrochloric acid, sodium dithionite in water and catalytic reduction with hydrogen in acetone or ethyl alcohol at various pressures and temperatures. The complete reduction of the nitroacid occurs only when using palladium on coal at a temperature of 100 °C and a hydrogen pressure of 40 atm or Raney nickel at 70 °C and a pressure of 65 atm H2 in ethanol. Raney nickel is very sensitive to catalytic poisons, even a small amount of impurities (such as alkali) left after the catalyst has been obtained and washed leads to its complete deactivation. Therefore, synthesis using Raney nickel, although possible, is inconvenient from a practical point of view. On the contrary, the complete reduction of the nitro group occurs at lower temperatures and pressures (50 °C, 25 atm) using palladium on coal as a catalyst after its additional activation with hydrogen. The structure of aminocarboxylic acids was confirmed by IR spectroscopy, 1H NMR spectra, elemental analysis and HPLC.
Thermodynamic modeling of phase equilibria in the system Na2O – CaO – Al2O3
Authors:   Chelyabinsk State University, Pratskova Svetlana E. , Nechaeva Evgenia S. ,   Chelyabinsk State University
Published: March 2021

The thermodynamic properties of melts of the Na2O – CaO – Al2O3 system are of considerable interest for metallurgy, technology of ceramic materials, optical fibers. State diagrams CaO – Al2O3, Na2O – Al2O3 have been studied by many researchers and do not have the generally accepted version, and the system Na2O – CaO has not been specifically studied. In the work, thermodynamic modeling of the phase equilibria of the Na2O – CaO – Al2O3 system was carried out within the framework of the generalized theory of “regular” ionic solutions. Equations for the activities of the system components are derived. The energy parameters of the model are determined taking into account melting characteristics and experimental data. The state diagrams of binary systems are constructed using the calculated values of the Gibbs energies for the formation of sodium and calcium aluminates from the corresponding oxides. Using the regression equations of the temperature dependences of the energy parameters of binary melts of the Na2O – CaO – Al2O3 system, the molar mixing functions of the liquid solution раствора G_m^M, H_m^M, S_m^M and the excess thermodynamic functions G^E, H^E, S^E were calculated at 1500-1800 oC. Lime-alumina melts are stable at all temperatures, experiencing negative deviations from ideality. The Gibbs excess energy G^E is negative and in absolute value varies from 5 to 90 kJ/mol. With an increase in the concentration of Al2O3 in the melt and temperature, a tendency toward disorder is clearly manifested: the entropy of the melt mixing changes its sign from “minus” to “plus”. Na2O – Al2O3 melts are formed with an exothermic effect and ordering, and are also stable. They experience strong negative deviations (for G^E) from ideality. However, the situation changes at 55 mol. % Al2O3 and 1700-1800 oС melts of the system are unstable.
Study of the possibility of using diafen FP, sulfenamide C and N,N’-dithiodimorpholine of domestic production in rubber mixtures instead of imported analogues
Authors:   JSC ", Efimovskiy Egor G. ,   Cheboksary Production Association named. V.I. Chapaeva”, Ushmarin Nikolay F. ,   JSC "Cheboksary Production Association named. V.I. Chapaeva”, Sandalov Sergey I. ,   JSC "Cheboksary Production Association named. V.I. Chapaeva”, Kol'tsov Nikolay I. ,   Chuvash State University  of I.N. Ulyanov, Golikov Alexey G. ,   State Research Institute of Organic Chemistry and Technology, Kostikova Natalia A. ,   State Research Institute of Organic Chemistry and Technology, Korneeva Oksana I. ,   State Research Institute of Organic Chemistry and Technology, Antonova Maria M. ,   State Research Institute of Organic Chemistry and Technology, Klimov Dmitry I. ,   State Research Institute of Organic Chemistry and Technology
Published: March 2021

The article presents the results of a study of various rubber compounds based on rubbers containing, in the composition, made by FGUP GosNIIOHT diafen FP, sulfenamide C and N,N'-dithiodimorpholine instead of imported analogues. Rubber compounds were made on a laboratory rubber mixer SKI-3L with Intermix rotors. After a day at room temperature, the rubber mixtures were vulcanized on a vacuum compression machine of column type a firm Panstone 3RT. The main technological indicators of rubber mixtures after their manufacture on the rolls were: ductility, ring modulus and density. These indicators characterize the processability of rubber mixtures in the manufacture of products from them. For the obtained vulcanizates, the elastic-deformation properties (conditional tensile strength, relative elongation at break, Shore A and ISO hardness, bond strength with metal at tearing, and abrasion resistance) were determined by standard methods. To assess the performance properties of rubbers, changes in conditional tensile strength, relative elongation at break, hardness, volume and mass after rubbers aging in corrosive media, as well as relative residual deformation of compression, temperature limit of brittleness and frost resistance were determined. The possibility of using diaphene FP, sulfenamide C and N,N'-dithiodimorpholine made by FSUE "GosNIIOHT" as part of various rubber mixtures instead of imported analogs is shown. The obtained rubbers according to the technological, elastic-deformation and operational properties comply with the requirements. These rubbers can be used for the manufacture of rubber-technical products with a special set of elastic-deformation and performance properties, and domestic ingredients manufactured by the Federal State Unitary Enterprise GosNIIOHT can be introduced into production.
Physiological properties of resistance strain Fusarium oxysporum
Authors:   Mendeleev University of Chemical Technology of Russia, Bulanov Alexander G. , Shagaev Anton A. ,   Mendeleev University of Chemical Technology of Russia, Belov Alexey A. ,   Mendeleev University of Chemical Technology of Russia, Markvichev Nikolay S. ,   Mendeleev University of Chemical Technology of Russia
Published: March 2021

Soil microorganisms have a significant effect on microbiological cenosis. Such communities are called the root micro-flora of the plant. All organisms in the microflora are divided into two groups: rhizoplane, living directly on the root system of the plant, and rhizosphere, developing in the root area of the plant. The intensive population of the root and root zones of a plant is primarily associated with the release (exosmosome) of organic substances or exudates formed during the life of the plant. The plant microflora includes not only symbiotic and commensalithic types of interaction, but also parasitic forms. Parasitic pathogens are divided into two groups: pathogenic and conditionally pathogenic. Conditionally pathogenic microorganisms are in a latent state and have an effect only when certain conditions arise for their activation and development. Such conditions may include changes in temperature, humidity, disturbance of plant homeostasis, or damage to the integument. Pathogenic microorganisms, by contrast, are always active and infect the host organism upon contact. The pathogenicity of a microorganism is a complex of traits that adversely affect the health of the plant, cause various pathologies, leading to growth inhibition and partial inhibition of the development or complete destruction of the culture. The pathogenic properties of the Fusarium oxysporum culture F201 were investigated against the cucumber culture by Atlet F1. It was shown the phytopathogenic microorganisms Fusarium oxysporum has acquired signs of resistance without lost her aggressiveness properties against a plant. Fusarium oxysporum quite comparable with the common strain.
Process modeling of the nickel and iron reduction from oxide melts by converted natural gas
Authors:   Institute of Metallurgy of Ural Branch of Russian Academy of Sciences, Vusikhis Alexander S. , Leontiyev Leopold I. ,   Institute of Metallurgy of Ural Branch of Russian Academy of Sciences, Chentsov Victor P. ,   Institute of Metallurgy, Ural Branch of the Russian Academy of Sciences, Selivanov Evgeny N. ,   Institute of Metallurgy, Ural Branch of the Russian Academy of Sciences
Published: March 2021

The converted natural gas using possibility to reduce iron and nickel from oxide melts in bubbled layer has been considered. The thermodynamic modeling technique has been applied to describe the kinetic features of the multicomponent oxide melts interaction processes with various compositions reducing gases. Various types of conversion is used to obtain it (oxygen, steam, carbon dioxide) are considered. Influence of the natural gas/oxidizer gas ratio and the temperatures at which the conversion is carried out to the converted gases compositions is estimated. It is shown that temperature increase from 1725 to 2273 K has little effect to the converted gases compositions. The hydrogen concentration in the products of oxygen conversion at CH4/O2 = 2 is 66.5%; steam (CH4/H2O = 1) is 75.0%; carbon dioxide (СН4/СО2 = 1) is 49.9% (the rest is CO), respectively. Oxidant addition leads to СО2 and water vapor appearance in the mixture. Bubbling kinetics is described by means of thermodynamic calculation. Reducing gas content and quantity (injected in oxide melt) affect to it properties is considered. The melt content changing, elements reduction degree, oxide and metal phases mass ratio, equilibrium contents of exhaust gases, etc are analyzed on this base. As was obtained, Nickel oxide residual content in the final melt have been decreasing to 0.03% and Nickel share in the ferronickel (formed in reducing process) is 70% in the case of oxidant absent. Residual NiO content in the oxide melt is higher, and degree of reduction is less in the presence of CO2 and H2O. The results obtained allow us to predict the metals reduction process parameters in the oxide systems melt babbling treatment. It has been found that the most efficient gas is steam reformed.
Study on the extraction of metals from tails of flotation enrichment of copper sulfide ores
Authors:   JSC Uralmekhanobr (UMMC–Holding Corp.), Musayev Vladimir V. , Klyushnikov Anton M. ,   JSC Uralmekhanobr (UMMC–Holding Corp.), Galimov Ramil R. ,   JSC Uralmekhanobr (UMMC–Holding Corp.)
Published: March 2021

Flotation processing of copper-pyrite ores is accompanied by the formation of flotation tailings containing 0.2-0.7 % wt Cu and 0.6-1.4 g/t Au. Deeper extraction of these components into commercial products is of practical interest. The possibility of additional recovery of copper and gold using the example of tailings from the current processing of PJSC “Gaysky GOK” was studied. It was shown that thin emulsion impregnation of chalcopyrite (less than 10 μ) in pyrite prevented the copper and gold from being extracted from the tailings by ore dressing methods. A scheme for the deep extraction of valuable components, based on the preliminary concentration of gold and copper by pyrite flotation, was proposed. About 84.5% of gold and 60.9% of copper were extracted into pyrite concentrate, while the gold content in the chamber product was 0.25 g/t. The increase in the extraction of copper was impossible due to nature of copper phase in chamber product that consisted mainly of copper oxides. Further processing of the pyrite concentrate can be accomplished by the way based on oxidative roasting (550-600 °C), with subsequent sulfuric acid leaching of copper from the calcine, washing and cyanidation of washed cake. Acid leaching is recommended to be done without external heating with solutions of 10-20 g/l of sulfuric acid. Copper was precipitated from leachates by cementation with iron powder in the form of copper concentrate (22-32 % wt Cu), then the gold-containing solution is processed to produce ligature gold. The optimal conditions for the cyanidation of the calcine were determined as follows, L:S = 2, the initial concentration of NaCN was 2 g/l, the duration of cyanidation was 2 hours The possibility of achieving end-to-end extraction of 66% of gold, and 45% of copper in commercial products is shown. The proposed scheme makes it possible to reduce the specific consumption of NaCN during cyanidation from 2.5-2.8 to 0.8 kg/t of tailings. It is assumed to gain sulfuric acid from the burning gases.
Viscivity of the B2O3-CaO-NiO (FeO) systems melts
Authors:   Institute of Metallurgy of Ural Branch of Russian Academy of Sciences, Vusikhis Alexander S. , Leontiev Leopold I. ,   Institute of Metallurgy of Ural Branch of Russian Academy of Sciences, Selivanov Evgeny N. ,   Institute of Metallurgy of Ural Branch of Russian Academy of Sciences, Chentsov Viktor P. ,   Institute of Metallurgy of Ural Branch of Russian Academy of Sciences, Ryabov Valery V. ,   Institute of Metallurgy of Ural Branch of Russian Academy of Sciences
Published: March 2021

Structure of the B2O3 melt was analyzed as well as CaO modifier additives (25, 34, and 45 mass %) effect to it. As was proved, non-ring groups of associated rings proper to pure B2O3 are transformed into BO2O – metaborate triangles. The released oxide ions increase the coordination number of modifying ions, which occupy cationic vacancies place in the most disordered part of the melt greed. The B2O3–CaO–NiO and B2O3–CaO–FeO melts viscosity were measured by the method of vibration viscometry. Ratio of Boron to Calcium oxide mass fractions was taken as 3/1 and content of Nickel and Iron oxides in the range up to 5 and 20 % mass respectively. The experiments had been carried out using vibration viscometer operating in the mode of forced oscillations. The melt temperature was measured by Platinum –Platinum – Rhodium thermocouple. The measurements were carried out in cooling mode of the melt from 1800 K at 7-10 K/min speed. The viscosity temperature dependencies as well as its dependence on Nickel and Iron oxides were determined. Data processing was performed using the Table curve application software. Viscosity experimental data of the B2O3-CaO-NiO system melts for 1373, 1423, 1473, 1523, 1573 K temperatures have been described by the equation: η = a + b·exp(-cx), and for B2O3 – CaO – FeO melts by equation: η = a + b·x2 + c·exp (x) + d·exp(-x). Experimental data and calculations results show good convergence. The results are supposed to be used for describing the kinetics of metal reduction in bubbling processes, accompanied by the concentrations change of the oxides under reduction. The obtained information is useful for correction the slag melts properties in non-ferrous metal production.
Prediction of physicochemical parameters of substances using the moment of inertia and recurrent relationships
Authors:   D.I. Mendeleev Russian Chemical-Technological University, Borisevich Igor S. , Kryshchenko Yury K. ,   D.I. Mendeleev Russian Chemical-Technological University, Ofitserov Evgeny N. ,   D.I. Mendeleev Russian Chemical-Technological University, Pozhidaev Viktor M. ,   Kurchatov Complex NBIKS-Nature-Like Technologies
Published: March 2021

Before scientists in science there was always a problem in predicting the physicochemical parameters of substances, in particular, members of homologous series. It often happens that data for a number of compounds of the homologous series may simply be absent. One of the most important characteristics of homologues is the boiling point. This value is directly related in gas chromatography to the retention time, however, it is impossible to create the same temperature conditions for chromatography of all compounds. On the other hand, according to some properties, for example, according to the melting temperature, the members of the series are divided into two contracts – even and odd. Phase transitions are associated with the loss or acquisition of one of the degrees of freedom. Analysis of chromatograms showed that by the retention time there is no division of the series into even and odd, which indicates the absence of adsorption of the adsorbate with the loss of the rotational degree of freedom. Based on this, the possibility of predicting these parameters using the moment of inertia of rotational motion and recurrence relations introduced into the chromatography by I. Zenkevich was investigated.
The study of the possibility of using domestic burnt magnesia in oil and petrol resistant rubber
Authors:   Chuvash State University  of  I.N. Ulyanov, Ushmarin Nikolay F. , Egorov Evgeny N. ,   Chuvash State University  of  I.N. Ulyanov, Kol'tsov Nikolay I. ,   Chuvash State University  of  I.N. Ulyanov
Published: March 2021

The article examines the oil-and-petrol resistant rubber mixture of type 7NO-68-1SK based on the combination of BNKS-18AMN grade butadiene-caoutchouc with polychloroprene caoutchouc of brand neoprene W. The effect of replacing imported burnt magnesia brand Remag AC on domestic burnt magnesia technical grade B on the properties of the rubber compound and vulcanizate was studied. The rubber mixture was prepared on a laboratory roll mill LB 320 160/160, and then its standard samples were vulcanized at 150 °C for 30 minutes in a two-story electrically heated press of the VP 400-2E brand. To establish the plasto-elastic properties of rubber mixture on the Mooney viscometer, MV 3000 was determined: the start time of the vulcanization, the time to reach the vulcanization mode, the initial maximum viscosity. To assess the kinetics of vulcanization of the rubber mixture on the rheometer MDR 3000 was determined: the start time of vulcanization, the time to reach the optimum vulcanization, the maximum torque. To assess the physicomechanical properties of rubber, the following were determined: conditional tensile strength; elongation at break; hardness; tear resistance and relative residual deformation under compression in accordance with the standards in force in the rubber industry. To assess the performance properties of rubber, changes in its mass were determined after aging in a mixture of isooctane + toluene, as well as standard liquid SJR–1. It has been shown that the introduction of burnt magnesia technical grade B into the rubber mixture does not lead to technological complications, magnesia is well distributed in the rubber matrix, and the magnesia agglomerates were not found on the rubber mixture sections. Replacement magnesium oxide m. Remag AC on burnt magnesia technical grade B has an impact on the plasto-elastic and rheometric properties of the rubber mixture. However of physicomechanical and operational properties vulcanizates of rubber mixture containing magnesium oxide m. Remag AC and burnt magnesiatechnical grade B, have almost the same values.
Prediction of octane numbers of substituted alkanes according to the topological characteristics of the molecules
Authors:   Ufa State Petroleum Technical University, Koledin Oleg S. , Kovaleva Ella A. ,   Ufa State Petroleum Technical University, Dolomatov Mikhail Yu. ,   Bashkir State University, Arslanbekova Svetlana A. ,   Bashkir State Agrarian University
Published: March 2021

There may occur a special mode of combustion of the fuel-air mixture called detonation, when using motor fuel with a low octane rating. Methods of mathematical modeling are currently used to quickly determine octane numbers without using of expensive equipment. A nonlinear multidimensional QSPR regression model is proposed to predict the octane number of normal and substituted alkanes-gasoline components. The model associates octane numbers with a set of descriptors (topological characteristics of molecular graphs): the Randic index, the Wiener index, and the functions of the eigenvalues of the topological matrix of the molecule, reflecting the main structural and chemical factors, such as branching, the length of the carbon structure and the energy parameters of the molecules, for example perturbation of Hückel spectrum of molecules, as well as affecting octane numbers. The substituted alkanes were used as research objects. A studied sample included 36 hydrocarbons from the homolologus serious of substituted alkanes. The proposed model adequately describes the octane number of alkanes. The coefficient of determination of the model is 0.972. The model was tested on 19 substances which were not included in the base series. The average, absolute and relative error for the test sample of octane numbers were 1.5 units and 2.7% respectively. The model is applicable for engineering and scientific forecasts of octane numbers of various alkanes in motor fuel.
Effect of 1,2,4-triazole derivatives structure on their sorption by hypercarb under RP HPLC conditions
Authors:   Samara National Research University, Kurnysheva Yulia P. , Ryzhkin Semen A. ,   Samara National Research University, Kurbatova Svetlana V. ,   Samara National Research University
Published: March 2021

The results of 1,2,4-triazole derivatives studies by high-performance liquid chromatography using water-acetonitrile mixture in various volume ratios as eluent are presented. A porous graphitic carbon – hypercarb was used as a sorbent. It has been shown that the main physicochemical parameters determining the sorption of 1,2,4-triazole derivatives under the conditions of RP HPLC are the lipophilicity, polarizability and the volume of analyte molecules. At the same time, almost all the investigated substances are relatively polar, which contributes to their interaction with the components of the polar mobile phase. In general, among the derivatives of 1,2,4-triazole selected for the study, the values of the molecular volume, polarizability, lipophilicity and dipole moment vary within relatively wide limits, which leads to significant differences in the sorption characteristics of these compounds, which are also determined by the nature of the sorbent. At the same time, a symbiotic relationship was established in changing the values of the retention factor of the studied substances, their polarizability and lipophilicity. The observed deviations from the dependences obtained are due to specific interactions of sorbate molecules with the components of the mobile phase. The effect of temperature on the chromatographic retention of azoles was investigated. The sorption isotherm of 2-(1H-triazol-1-ylmethyl) phenol is obtained, which is almost linear in the initial part, which corresponds to the Henry region. The thermodynamic sorption characteristics of triazole derivatives have been experimentally determined. It is established that the values of changes in standard molar enthalpy and Gibbs energy of sorption during the transition of the molecules of the analyzed analytes from the bulk solution to the surface layer of the hypercarb are predominantly negative, which indicates the exothermic process and its spontaneous flow. At the same time, these values lie in a relatively narrow range and are determined mainly by the nature of the substituent and its position in the heterocycle.
Influence of the method of disintegration of biomass of microalga Chlorella sorokiniana on the production of lipid fraction
Authors:   Peter the Great St. Petersburg Polytechnic University, Smyatskaya Yulia A. , Politaeva Natalia A. ,   Peter the Great St. Petersburg Polytechnic University, Toumi Amira ,   Peter the Great St. Petersburg Polytechnic University
Published: March 2021

This article discusses the effect of the disintegration of the cell wall of the microalgae Chlorella sorokiniana on the output of the lipid fraction. The biomass of the microalgae Chlorella sorokiniana was grown under laboratory conditions in special photobioreactors at a temperature of 25 °C, with a constant aeration of a mixture of carbon dioxide and air at a rate of 1.5 liters/min, illumination 2200-2800 Lx. Nutrient medium for cultivation contained macro – and micronutrients for high-speed growth of microalgae. Selection of optimal cultivation parameters allows obtaining biomass with desired properties. Disintegration was carried out with the homogenization of biomass and under the influence of microwave radiation. Extraction of lipids was carried out on a semi-automatic extractor according to the Randall method, using organic solvents. The output of the lipid fraction without treatment was 10.18% after the destruction of the cell wall 14.45% with the homogenization of biomass and 13.85% under the influence of microwave radiation. A qualitative analysis of the lipid fraction, carried out under gas chromatography, obtained under various conditions showed that there was no significant difference in composition from the disintegration method. Lipid fractions (more than 50%) in both cases consist mainly of unsaturated fatty acids, of which irreplaceable unsaturated fatty acids constitute more than 18% for both samples. The residual biomass formed after the extraction of the lipid fraction can be used as fertilizer in the plant, for the manufacture of sorption materials for the purification of industrial water and as a biofuel. The purpose of this study was to study the effect of cell wall disintegration on the output of the lipid fraction and qualitative composition.
Toxicity assessment of residual biomass of microalgae Chlorella sorokiniana
Authors:   Peter the Great St. Petersburg Polytechnic University, Smyatskaya Yulia A.
Published: March 2021

In this paper, the determination of the toxicity of residual biomass of microalgae Chlorella sorokiniana by the method of biotesting with use of the test – object Daphnia magna Straus and algae Chlorella vulgaris Beijer. Determination of the toxic effect is necessary for planning the possibility of further use of waste, as a sorption material for wastewater treatment, as a co-substrate for fermentation of organic waste and in the production of biogas. The residual biomass of Chlorella sorokiniana microalgae is formed after the extraction of valuable components (lipid complex, pigments, proteins, etc.). The extraction of the lipid complex uses organic solvents (hexane, ethyl alcohol), the remains of which can remain in the residual biomass. Determined the acute toxicity of residual biomass of microalgae by water extraction with the help of test-object Daphnia magna Straus and the test object microalgae Chlorella vulgaris Beijer according to standard methods. According to the study waste source of residual biomass to treat the IV class of hazard, ЛКР50-48 = 11.7; БКР10-48 = 35.48. To reduce the toxic effect is proposed to conduct heat treatment. Heat treatment was carried out in a muffle furnace at a temperature of 105 oС for 1 hour. Experimental studies using Daphnia magna Straus crustaceans showed that the value of A is 3%, which indicates the absence of toxicity of residual biomass. When using microalgae toxicity criterion was also not exceeded in any dilution of water, including its original undiluted version. It is established that after heat treatment the residual biomass of microalgae becomes non-toxic and has a V hazard class. The results indicate the possibility of re-use of residual biomass.
Impact of COVID-19 Pandemic and Lockdown Measures on Mental Health
Authors: Gul Tahira , Amir Lubna , Abbasi Sophia , Bilal Hazrat , Gul Shazia
Published: March 2021

Background: An Uncontrolled Novel COVID-19 started from Wuhan city of China in Late 2019 and spread worldwide has called for unprecedented measures, to prevent it Pakistan government Imposed lockdown on the entire country. Lockdown has a huge impact and affected on mental health of population. The present study aims to assess the effect of COVID-19 on mental health of population and identify the coping strategies to overcome this mental health issues caused by pandemic.
Methods: An online survey was administered from 26 May-14 June 2020 to 398 participants. Post Hoc test was performed to examine the associations between general health questionnaire GHQ-12 and socio-economic variables.
Results: Losing jobs due to pandemic and lockdown situation and using negative coping strategies were the factors associated with psychological disorders.This study shows high rates of anxiety and stress in younger population specifically in young women with higher odds of endorsing a worst mental health outcome. Outcomes were associated with a number of COVID-19 related risk factors such as challenging family relations, loss of job, no physical activity, financial burden, experiencing stress full events and suicidal ideation.
Conclusion: The present situation requires awareness in public media which could be helpful to deal with this and this present article provides details of COVID-19 pandemic situation on mental health of younger population.
Fan fiction comments and their relationship to classroom learning
Authors: Rouse Lauren
Published: March 2021

Reader comments appended to online fan fiction stories provide benefits as close reading and critical analysis tools. Fan fiction provides a space where fans can develop literary analysis skills and literacy through their interactions in comments. This multimethod study combined the interview of a fan author with various digital humanities methods to closely study the value of comments. A web scraping tool was used to collect comments, and documentary, textual, and terminological analyses were performed alongside topic modeling to assess the frequency of words associated with learning. The co-occurrence of certain words was studied to understand the assessments and analyses that readers were performing in their comments. The study found that fan fiction readers apply strategies of literary analysis to their pleasure reading.
Affirmational canons and transformative literature: Notes on teaching with fandom
Authors: Zygutis Linda
Published: March 2021

Instructors who use fan studies in the classroom are likely to make use of transformative works and theories. The remix classroom offers a way to read against popular interpretations of mainstream texts. In the process, teaching with fandom—not to mention fandom itself—is often presented specifically as a salve to prescriptive readings of texts. Yet fan practices are often imagined by mainstream culture as being uniquely affirmational—a particularly enthusiastic form of close reading that emphasizes and rewards deference to an authorial voice. In this sense, the way media and popular culture understand fandom is as an extension of how students are often taught to read texts: via a formalistic, New Critical approach that centers authoritative criticism. Students who interact with fan texts but do not see themselves as fans feel this way, just as students often fail to recognize themselves as critical readers because expertise has been made into a form of gatekeeping.
Context, cosplay, and (re)configurations: Centering the geek at the heart of science fiction pedagogy
Authors: Keramidas Kimon , Haborak Fiona
Published: March 2021

The course "Science Fiction: Humanity, Technology, the Present, the Future" uses fandom as a motivator for pedagogical development, promoting participation and engagement by encouraging students to embrace their fan passions. In classroom discussions, website commentary, Geek of the Week presentations, and a final prototype project where science fiction texts are reimagined as nonlinear user-driven experiences, students are given a role in shaping the content and trajectory of the course. Two perspectives are provided, one from a professor and one from a former student, on the course, its syllabus and assignments, and the ways in which the students' participation in fandom helps influence the hierarchies, balance, and flow of the course. By exploring new approaches to course development and more democratic classroom experiences through concepts such as affinity spaces, participatory culture, and design thinking, the course proposes a fan pedagogy that best contextualizes science fiction as a genre, field, and space for cultural commentary.
Students as fan, or Reinvention and repurposing in first-year writing classrooms
Authors: Mcclantoc Keshia
Published: March 2021

I performed a study of two first-year writing classrooms and their interactions that used a fan fiction–based pedagogy. Rather than using fan fiction as class texts, this pedagogy used the fan fiction practices of reinventing and repurposing to help students better understand themselves and their community. This was done to position the students as fans themselves. Students were challenged to act as a fan would as they moved through myriad overlapping fan fiction and composition studies practices. I include descriptions of major assignments, examples of student writing, and reflections on both the successes and struggles within this classroom.
Exploring film history by using fandom as a pedagogical tool
Authors: Wright Ellen
Published: March 2021

An exploration of the terrain of how to engage learners effectively and why that matters. Using fan engagement in the field of film history reveals that encouraging learners to self-identify as fans shifts the power balance, placing the learner in the position of expert, thereby increasing the chances of learner engagement and enabling learners to gain a more nuanced understanding of their field while also making for a more invested, lively, and varied learning and teaching experience. Based on firsthand experience designing and delivering a research-focused undergraduate film history module combined with a multidisciplinary pedagogical approach, this work demonstrates that treating students as fans with affective stakes in history and exploring historical moments experientially offers learners significant benefits.
Evaluating fandom: Using blogging and a grade contract to promote fan labor in the classroom
Authors: Ashby Dominic J.
Published: March 2021

Grade contracts offer a way to transform the relationship between labor and assessment in classrooms. By turning attention from evaluations of quality to labor completed, grade contracts make space for students to shift from a grade-driven extrinsic motivation to an interest-driven intrinsic motivation for completing coursework. Such an assessment model is well suited for fan studies classes where instructors ask students to engage in fan behavior. I share how I built an upper-division course about anime and anime fandom centered around a student-authored, publicly viewable blog. I discuss the synergy between the blogging project and a grade contract that enhanced student learning, engagement, and enjoyment. I also share my course design philosophy, approach to blogging, and student reactions to the grade contract.
Chinese celebrity fans during the Covid-19 pandemic
Authors: Lai Yang
Published: March 2021

Connected learning is a valuable tool that may be used in China to mitigate the stigma of fan activities, as a case study of Chinese celebrity fans' activities during the coronavirus outbreak in China illustrates.
A brief review of fan studies in Brazil
Authors: Amado Aianne
Published: March 2021

Analysis of the current state of the field of fan studies in Brazil, recognizing the importance of acknowledging social, political, economic, and historical factors when studying fandoms.
Madonna and her multicultural fan community
Authors: Pulos Rick
Published: March 2021

Analysis of Madonna as the center of a community demonstrating how women can exist at the center of life in a deep community structure.