bluuebunny/crossref_metadata_2025 huggingface dataset:
The regularities of the formation of carbon nanostructures from hydrocarbons based on the composition of the reaction mixture
Authors: Vedyagin Alexey A. , Korneev Denis , Mishakov Ilya , Streltsov Ivan , Vinokurova Olga , Bauman Yury
Published: March 2023

This paper presents the results of research on the regularities of the formation of carbon nanofibrous materials, as well as the influence of the composition of the model mixture of hydrocarbons S1–S4 on the morphological features and textural characteristics of the resulting carbon nanofibres (CNF).One of the most urgent issues faced by the oil and gas industry is how to increase the processing depth of associated petroleum gas (APG). In the Russian Federation alone, the annual economic losses from unutilisedAPG during processing are estimated at 2 billion dollars. It is known that the composition of APG can vary greatly, depending on the oil and gas field. In particular, the methane concentration, the main component of natural gas and associated gas, varies from 25 to 95 vol.%. In this study, we sought to identify the main factors that determine the morphology and structure of CNF, and to develop approaches in processing actual hydrocarbon mixtures to produce a carbon product with the desired or predictable characteristics. Such an approach can serve as a basis for resource-saving catalytic technology utilizing C1–C4 hydrocarbons that are currently disposed of as post-combustion flare gas. The research results clearly demonstrate that the morphology and texture of the carbon materials obtained by the decomposition of hydrocarbon mixtures depend on the composition of the reaction gas. The key components in this case are methane and the resultant hydrogen: their relationship at a specific temperature determines the direction of the reversible reaction of carbon hydrogenation: S + 2H2 = SH4. The decisive factor in the decomposition of hydrocarbons yielding carbon materials is the degree of deviation of the methanation reaction from equilibrium which can be influenced in two ways. The addition of hydrogen to the reaction gas promotes the driving force of the carbon hydrogenation reaction, resulting in defective high-surface carbon fibres. Increasing the concentration of methane in the reaction gas composition, in contrast, reduces the driving force of methanation until the process is suppressed, which promotes a more structured form of the CNF, without defects.
Advanced technology of transformer winding condition control based on nanosecond probing impulse
Authors: Mytnikov Alexey V. , Lavrinovich Valeriy , Li Hongda
Published: March 2023

One of the prospects of resource-effective technologies in power industry is control of electric equipment condition. Effectiveness of any electrical energy system strongly depends on stable work of power supply equipment. It, in turn, is defined by timely and reliable control of equipment condition. Power transformers are the key element of an electrical energy system.Winding defects caused by short circuit currents are the reason for an emergency situation. Reliable control of winding condition is an urgent task of modern power engineering technology. This paper deals with the experimental research of pulsed method of transformer winding control. A new approach to the winding condition control technology is described. The proposed method is based on short nanosecond range (compared to typical pulsed technology) probing impulse andfront impulse durations. Experimental results of sensitivity growth at the nanosecond probing impulse duration are shown. Experimental equipment and measurements are described. Comparison of experimental results of the proposed pulsed method and FRA is given. It is shown that probing impulse of nanosecond duration allows upgrading sensitivity of diagnostics procedure. The main proposals are confirmed by measurement results obtained in the electric energy system transformer for different types of winding defects.
On the behaviour, mechanistic modelling and interaction of biochar and crop fertilizers in aqueous solutions
Authors: Pandit Aniruddha , Simha Prithvi , Yadav Ashish , Pinjari Dipak
Published: March 2023

Although the benefits of applying biochar for the purposes of soil conditioning and crop productivity enhancement have been demonstrated, relatively few studies have elaborated on its causal mechanisms, especially on the biochar–fertilizer interaction. Thus, in the present study, the ex-situ adsorptive potential of base activated biochar (BAB) towards plant nutrient immobilization and removal from aqueous solutions wasinvestigated. Napier grass (Pennisetum purpureum) was utilized as the precursor to prepare slow vacuum pyrolysed char and its affinity towards adsorption of urea was examined at various process conditions. Low sorption temperatures, moderate agitation speeds and high initial concentration were seen to favour greater urea uptake by BAB. The sorption was exothermic, physical, spontaneous and had a pseudo-second order kinetic fit. Both surface and intra-particle diffusion governed the removal and immobilization of urea. Furthermore, process mass transfer was limited by film diffusion of urea to the external surface of the BAB. Equilibrium studies suggested that Dubinin–Radushkevich is the most appropriate model to describe the urea-BAB behaviour with maximum uptake, estimated to be 1115 mg·g−1. Through such ex-situ analysis, it could be possible to have prior knowledge, quantification and differentiation of the potential of chars manufactured from various feedstocks. This could then be used as an effective screening step in designing appropriate biochar–fertilizer systems for soil conditioning and help reduce the time and effort spent otherwise in long-term field studies.
Dry sliding wear studies of aluminum matrix hybrid composites
Authors: Manikandan Venugopal , Joseph M. A. , Rajendrakumar P. K.
Published: March 2023

In the present work, hybrid composites are fabricated with self-lubricating characteristics to make them as resource-efficient materials.AA6061-10 wt. % B4C–MoS2 hybrid composites reinforced with 2.5, 5 and 7.5 wt. % concentration of MoS2 particles are produced using stircasting technique, and mechanical and tribological properties are evaluated. Microstructural characterization of the hybrid composites revealed theuniform distribution of reinforcement (B4C and MoS2) particles in the matrix material. Hardness and fracture toughness of the hybrid compositesare decreased monotonously with an increase in the addition of MoS2 particles. Dry sliding tribological studies conducted using a pin-on-disktribotester under atmospheric conditions revealed the formation of MoS2-lubricated tribolayer on the worn pin surface which significantlyinfluenced the tribological properties. The addition of MoS2 particles decreased the friction coefficient and wear rate of the hybrid composites.Delamination and abrasion are observed to be the controlling wear mechanisms and material in the form of platelet-shaped debris, and flow-typechip debris is formed, and a long and shallow crater on the worn pin surface of the hybrid composite is also observed.
Applications of Box–Behnken experimental design coupled with artificial neural networks for biosorption of low concentrations of cadmium using Spirulina (Arthrospira) spp.
Authors: Madhu G. M. , Kiran Reddy Siva , Kalpana G. , Rangaiah G. Subba , Suggala Venkata Satyanarayana
Published: March 2023

The present study deals with the application of artificial intelligence techniques coupled with Box–Behnken (BB) design to model the processparameters for biosorption of cadmium using live Spirulina (Arthrospira) spp. as adsorbent in open race way pond with Zarrouk medium. Thebiomass concentration of Spirulina spp. decreased to half at 4 ppm Cd (II) after 8 days. Based on the LCt50 values, 3.69 ppm (8th day),Spirulina (Arthospira) maxima showed maximum tolerance. Considerable growth and bioaccumulation of Spirulina spp. is observed below1 ppm and tolerant up to 3 ppm. The cadmium adsorption on Spirulina spp. showed good correlation (R2 = 0.99) when applied to Freundlichequation and data fit into pseudo second order kinetics. A four factorial, three blocks and three level Box–Behnken design with initialconcentration (1 ppb to 5 ppb), biosorbant dosage (0.1 gdw to 0.2 gdw), agitation speed (12 rpm to 16 rpm) and pH (6 to 8) as independentvariables and percentage adsorption as dependent variable were selected for study. The data were further processed using artificial neuralnetwork model and DIRECT algorithm for better optimization. The final Cd (II) concentration of <0.5 ppb was achieved with 1 ppb initialconcentration under optimal conditions. A continuous desorption process was also developed for removal of cadmium from Spirulina (Arthrospira)sp.
Efficient continuous removal of nitrates from water with cationic cellulose nanopaper membranes
Authors: Mautner Andreas , Bismarck Alexander , Kobkeatthawin Thawanrat
Published: March 2023

Nitrates constitute a severe problem for the quality of potable water. The removal of nitrates from water can be performed utilizing continuouslyoperating cellulose nanopaper ion-exchangers, which so far are unfortunately of only moderate efficiency. Here we demonstrate cationic cellulosenanopapers comprising cellulose nanofibrils carrying a high amount of ammonium groups (1.6 g mmol−1, i.e. 0.62 mmol g−1), which areanticipated to enable efficient removal of nitrate ions from aqueous solutions. Thin nanopapers were shown to have high adsorption capacities.Therefore we prepared low grammage nanopapers using a papermaking process from cellulose nanofibrils prepared from paper mill sludge. Theperformance of these cationic nanopapers was characterized by their permeance, with these new cationic nanopapers having a permeance of morethan 100 L m−2 h−1 MPa−1, which is far greater than the permeance of conventional nanopapers. Furthermore, nitrate ions were successfullyremoved from water by capturing them through adsorption onto the cationic nanopaper by primarily an ion-exchange mechanism. These cationicnanopapers possessed adsorption capacities of almost 300 mg g−1, which is superior to commonly used nanopaper ion-exchangers and batch-wiseapplied adsorbents. Utilization of an industrial side-stream in combination with very good membrane performance demonstrates the use ofresource efficient technologies in an important sector.
Equilibrium and thermodynamic parameters for heterogeneous esterification of butyric acid with methanol under microwave irradiation
Authors: Rathod Virendra , Dange Paramanand
Published: March 2023

Synthesis of methyl butyrate was investigated in a microwave irradiated batch reactor in presence of acid ion-exchange resin catalyst,amberlyst-15. Methyl ester was heterogeneously produced by the reaction between butyric acid and methanol. Effect of reaction parameters oftemperature (323–343 K), catalyst loading (0–10.5% w/w), alcohol to acid ratio, M (1–5), and amount of molecular sieves added (0–13.5% w/w)on conversion were studied. Equilibrium conversion of 92.6% was achieved in 60 minutes under microwave irradiation. Equilibrium constants atvaried temperatures and dependency of equilibrium constant on temperature were studied. Equilibrium constant and equilibrium conversionshowed increase with the increase in temperature as expected as per le-Chatelier principle. Van’t Hoff plot for esterification of butyric acid waslinear with negative slope indicating that reaction was endothermic. Comparative study showed that microwave irradiated method for methylbutyrate synthesis to be very efficient and fast compared with conventional and ultrasound assisted routes under optimized reaction conditions.
Synthesis of a reusable novel catalyst ( β-tricalcium phosphate) for biodiesel production from a common Indian tribal feedstock
Authors: Sharma Yogesh Chandra , Madhu Devarapaga
Published: March 2023

In recent times, the rate of energy consumption goes on increasing and the world is desperately searchingfor new sources of fuel. Biodiesel (fatty acid methyl esters) is an alternative renewable energy resourcefor the next generation. Biodiesel has several advantages which include its non-toxic nature, itis biodegradable and it reduces greenhouse gas emissions. β-Tricalcium phosphate ( β-Ca 3 (PO 4 ) 2 ) catalystwas synthesized from fish waste. Fish waste contains calcium phosphate which is converted intoβ-tricalcium phosphate since it has low crystallinity and hydroxyl (OH) groups which decrease the potentialto be a good catalyst for the synthesis of biodiesel through transesterification. This paper exploresthe synthesis of biodiesel using β-tricalcium phosphate ( β-Ca 3 (PO 4 ) 2 ) as a heterogeneous catalyst.Pongamia pinnata (Karanja) oil was extracted from seeds through the solvent extraction process. Intendedfor the development of easier transesterification process, stable and active heterogeneous β-tricalciumphosphate ( β-Ca 3 (PO 4 ) 2 ) catalyst was synthesized and used for the P. pinnata (Karanja) oil transesterificationprocess. The synthesized heterogeneous catalyst was characterized by XRD, FT-IR, SEM and EDX todetermine its structural and morphological characteristics. The catalyst exhibited good catalytic activityon reuse. Biodiesel yield was greatly dependent on operating parameters such as catalyst concentration,methanol to oil molar ratio, reaction temperature and reaction time. Effect of co-solvent on biodiesel wasstudied by using different co-solvents in transestrification reactions. High quality and maximum biodieselyield (97 %) was obtained under the optimized reaction conditions (methanol to oil molar ratio, 10:1(tetrahydrofuran (THF):methanol 1:1); reaction time 90 min; catalyst concentration 2.5 wt % and stirrerspeed 650 rpm at 65 °C). Reusability of catalyst was examined up to five runs and found the catalyst wasreusable up to five times without much loss of catalytic activity.
Removal of chlorobenzene and 1,4-dichlorobenzene using novel poly-o-toluidine zirconium(IV) phosphotellurite exchanger
Authors: Mohan Aparna , Nimisha K. V. , Janardanan C.
Published: March 2023

Novel hybrid exchanger poly-o-toluidine zirconium(IV) phosphotellurite was synthesized and physico- chemical properties of the material were well studied by FTIR, XRD, TGA, SEM-EDX and TEM analysis. The composite exchanger showed good ion exchange capacity and excellent removal potential towards US En- vironmental Protection Agency listed priority pollutants like chlorobenzene and 1,4-dichlorobenzene. The factors affecting the adsorption like time, pH and temperature were studied in detail using UV spectrophotometry. More than 90% of the pollutants were successfully removed using the exchanger. The composite also showed selectivity towards heavy metal ions, especially mercury ions. The sorption kinetics of the material was studied in detail using pseudo first order and pseudo second order kinetics. The material followed pseudo second order kinetic model indicating chemisorption of the pollutants. The composite can be successfully used for environmental remediation purposes.
Development of sunlight-driven eutectic phase change material nanocomposite for applications in solar water heating
Authors: Narayanan S. Shankara , Kardam Abhishek , Verma Abhishek , Kumar Amiot , Madhwal Deminder , Bhardwaj Nitin , Shukla Prashant , Jain V. K. , Kumar Vivek
Published: March 2023

Organic phase change materials (PCMs) have been utilized as latent heat energy storage medium foreffective thermal management. In this work, a PCM nanocomposite, consisting of a mixture of two organicPCMs (referred to as eutectic gel PCM) and minimal amount (0.5 wt%) of nanographite (NG) as asupporting material, was prepared. Differential scanning calorimeter was used to determine the meltingtemperature and latent heat of pristine PCM, paraffin (61.5 °C and 161.5 J/g), eutectic gel PCM (54 °C and158 J/g) and eutectic gel PCM nanocomposite (53.5 °C and 155 J/g). The prepared PCM nanocompositesexhibited enhanced thermal conductivity and ultrafast thermal charging characteristics. The nanocompositeswere employed for two different applications: (i) providing hot water using an indigenously fabricatedsolar water heating (SWH) system and (ii) solar rechargeable glove that can be rapidly warmedand used. Experimental results on SWH system show that the use of PCM nanocomposites helps to increasethe charging rate of PCM while reducing the discharging rate of heat by PCM to water, thus enhancingthe maximum utilization of solar energy and hence improving the efficiency of the SWH system.The experimental results on solar rechargeable glove revealed that the glove has the ability to retain thetemperature up to 3 hours.
Bio-enrichment of phenolics and antioxidant activity of combination of Oryza sativa and Lablab purpureus fermented with GRAS filamentous fungi
Authors: Duhan Joginder Singh , Sadh Pardeep , Saharan Pooja , Duhan Surekha
Published: March 2023

Cereal and legumes meet a considerable requirement of protein and carbohydrate of the local population. Most of the foods are cereal based but some cereal/legume or legume based foods are also common in many countries of Asia and Africa. In present study, the effect of fermentation on total phenolics, antioxi- dant activity and α-amylase enzyme activity of ethanolic extracts of each of seeds and flours combination (1:1) of Oryza sativa (rice) and Lablab purpureus (seim) was determined. The percentage inhibition of free radicals formation by DPPH and ABTS assays was found maximum i.e. 80.66 ±0.21, 97.67 ±0.35 on 4th day of incubation of combined sample of rice and seim seeds fermented with Aspergillus oryzae and As- pergillus awamori, respectively. The increased percentage inhibition of free radical formation of fermented samples was found greater than the non-fermented samples (65.88 ±0.15, 42.00 ±0.63). The TPC of sub- strate i.e. rice:seim seeds (1:1) was also found maximum i.e. 47.53 ±0.20 on 5th day of fermentation with A. awamori . α-amylase activity of fermented samples was also found higher than that of non fermented samples. Almost similar results were obtained in combined flour extract of both the substrates. Increase in level of α-amylase enzyme during SSF indicates that enzymes produced by microorganisms were re- sponsible for release of bound phenolics which may be responsible for increase in antoxidant activity of extracts of fermented seeds and flour combination a cereal and a legume.
An experimental analysis of quenching of continuously heated vertical rod with aqueous Al 2 O 3 nanofluid
Authors: Patra Nirupama , Nayak Arun K. , Gosh Pradyumna , Singh Ravi
Published: March 2023

Quenching characteristics of metallic vertical rod with an internal heater has been investigated in pure water and water-based nanofluid with alumina nanoparticles of 0.001% by volume. Initial temperature of the testing rod (12 mm diameter and 10 0 0 mm length) ranges from 200 °C to 250 °C. The internal heater may be used to simulate the decay heat generated by the nuclear fuel rod after the power plant shut- down. Tests have been performed with varied range of experimental conditions of decay heat, constant water and nanofluid flow rates. The cooling curves follow a general trend of a rapid temperature drop up to almost 100 °C of the rod surface temperature irrespective of the operating parameters and the location of the thermocouple. The obtained results during quenching process indicated that HTC (heat transfer coefficient) for nanofluids are more than de-ionized water. It was also observed that in identical circum- stances, the quenching time of the specimen in Al 2 O 3 nanofluid considerably decreased as compared to water. The results exhibit that nanofluids can enhance the reflood heat transfer performance in terms of quenching rate for a long vertical rod causing liquid-droplets-induced depositions of nanoparticles result- ing in making a pre-coating effect characterized by higher wettability.
Statistical optimization of acid catalyzed steam pretreatment of citrus peel waste for bioethanol production
Authors: Appusamy Arunagiri , Indulekha John , Kalaichelvi P. , Muthih Perumalsamy , Prasanthi Yaragarla
Published: March 2023

Citrus waste is an attractive lignocellulosic biomass for the production of bioethanol due to the richness in carbohydrates and low lignin content. In this study, sweet lime peel was chosen as the lignocellu- losic biomass. To increase the cellulose for enzymatic hydrolysis, the statistical optimization of process parameters namely, solid loading, time of exposure and sulphuric acid concentration for pretreatment of sweet lime peel were accomplished by Taguchi orthogonal array design. The sweet lime peel was exposed to acid catalyzed steam pretreatment for solid loading [10%, 12%, 15% and 17% (w/v)], time of exposure [15 min, 30 min, 45 min and 60 min] and sulphuric acid concentration [0.25%, 0.5%, 0.75% and 1% (v/v)]. The cellulose content was found to be an optimum at 35% for 17% (w/v) solid loading and 0.25% (v/v) acid concentration and steam exposure for 60 min. With these optimized process parameters, enzymatic hy- drolysis of pretreated sweet lime peel was investigated at 50 °C for 48 h using in vitro isolated enzymes, viz., cellulase and pectinase from Aspergillus Niger with an activity of 1.7 FPU/ml and15 IU/ml respectively. 7.09 mg of reducing sugar/ml of hydrolysate was released in enzymatic hydrolysis which was estimated by DNS method. For the production of bioethanol, fermentation of hydrolysate was carried out at 30 °C for 72 h using baker’s yeast. The yield of ethanol was 18%. From this study, it is proved that citrus waste is a promising source for the production of bioethanol.
Heat transfer coefficients and productivity of a single slope single basin solar still in Indian climatic condition: Experimental and theoretical comparison
Authors: Agrawal Abhay , Srivastava Pankaj , Rana Ravindra Soingh
Published: March 2023

A theoretical and experimental study was conducted at the central Indian location of Rewa, M.P., India (Latitude: 24 °33 20.81 N, Longitude: 81 °18 49.1 E). This paper presents a detailed comparison of the theoretical and the experimental results obtained for a single sloped basin type solar still. Results for dif- ferent parameters such as basin water temperature, glass cover temperature, distillate output, evaporative, convective and radiative heat transfer coefficients and attenuation factor were obtained for basin water depths ranging from 2 cm to 10 cm. For solar still, daily distillate output decreased with increase in basin water depth. The theoretical value of daily efficiency for 2 cm and 10 cm basin water depth was around 52.83% and 41.75%, respectively, and for the same basin water depth, experimental daily efficiency was around 41.49% and 32.42% respectively. A sound agreement between the theoretical and the experimental results was observed.
Virtual lab based real-time data acquisition, measurement and monitoring platform for solar photovoltaic module
Authors: Rohit Amit Kumar , Tomar Amit
Published: March 2023

The work presents real-time data acquisition and monitoring of solar photovoltaic modules using Lab-VIEW. A graphical program has been developed to obtain efficiency and fill factor of solar PV module. Afront panel is designed, displaying all the acquired data such as; voltage, current, solar radiation, ambienttemperature, humidity, Current vs. Voltage and Power vs. Voltage graphs which make it very useful tounderstand the performance behavior of the solar photovoltaic module in real time. Data acquisition andmonitoring for solar panels of different ratings are carried out. This tool is an effective platform for experimentalstudy in the laboratory of different solar photovoltaic modules with access to real-time data.
THERMODYNAMIC UNCERTAINTY RELATION AS A FUNDAMENTAL ASPECT OF QUANTUM THERMODYNAMICS
Authors: Artamonov Anton А. , Plotnikov Еvgeny
Published: March 2023

The paper addresses physics of thermodynamic fluctuations in temperature and energy. These fluctuations are interrelated and, hence, can affect various micro- and macro systems. It is shown that the thermodynamic uncertainty relation must be taken into account in the physics of superconductivity, in quantum computations and other branches of science, where temperature and energy fluctuations play a critical role. One of the most important applications of quantum thermodynamics is quantum computers. It is assumed that in the near future the state structures will create a specific quantum cryptocurrency obtained using quantum computing. The quantum cryptocurrency exhibits two main features: the maximum reliability (quantum protection against hacking threats) and the possibility of state control (at the moment, only large scientific state centers have quantum computers).

The paper reviews the studies aimed to theoretically prove the validity of the thermodynamic uncertainty relation. This relation connects fluctuations in temperature and energy of a system. Other similar relations are considered, including the relationship between fluctuations in pressure and volume, in entropy and temperature, and others. The main purpose of the paper is to validate the thermodynamic analogue of the uncertainty relation that interconnects temperature and energy fluctuations.

Experimental data was obtained on the basis of the study of the transport properties of semiconductor devices – transistors. In the experiment, the transport properties of a pair of semiconductor transistors placed on a single silicon crystal were studied. In this system, one transistor was used to determine temperature fluctuations, and the other one was employed to estimate energy fluctuations.

The key role of the thermodynamic uncertainty relation in modern thermodynamics has been clarified. The performed experimental studies confirm the validity of the thermodynamic uncertainty relation.
Cleaning and sputtering using planar acoustoplasma magnetron
Authors: Abrahamyan A.S. , Mkrtchyan A.H. , Nalbandyan V.V. , Hovhannisyan H.T. , Chilingaryan R.Yu. , Hakobyan A.S. , Mossoyan P.H.
Published: March 2023

Абстрактные. В статье описаны полученные экспериментальные результаты для планарного акустоплазменного магнетрона. Небольшой радиус анодной петли позволяет фокусировать и ускорять ионный компонент распыленного материала. В качестве буферного газа использовали аргон. Сравниваются характеристики магнетрона в случае постоянного тока и в акустоплазменном режиме (AP) (с модулированным током, содержащим постоянные и переменные компоненты). Скорость распыления в режиме AP увеличивается. Для медного катода давление газа составляло <1 Па и плотность тока порядка 100 мА / см 2с увеличением расстояния от анода до осажденного субстрата от 2 до 4 см в случае подачи постоянного тока скорость осаждения снижается в 3,3 раза (от 17 до 5 нм / с), в акустоплазменном режиме - в 2 раза (от 13 до 6,4 нм / с). Для расстояния анода-подложки 4 см прирост скорости осаждения в режиме AP по сравнению с DC составляет 1,2-1,5 раза. Измерялись зависимости ионного и электронного токов на подложке от разных параметров разряда. Исследование основано на схеме с двумя потенциальными сетками с фиксированными и переменными потенциалами. Показана возможность формирования кольцевого пароплазменного потока быстрых частиц.
PECULIARITIES OF ELECTROMAGNETIC OSCILLATIONS GENERATED BY A CHARGED PARTICLE CROSSING THE PLANAR BOUNDARY BETWEEN A CONDUCTING MEDIUM AND A VACUUM
Authors: Grigoryan Levon Shavigh , Mkrtchyan Artak Henrik , Khachatryan Hrant Frunzik , Grigoryan Mher Levon , Sargsyan Anush Vahagn , Mosoyan Petros Hovhannes
Published: March 2023

The peculiarities of electromagnetic oscillations generated by a charged particle moving rectilinearly and uniformly have been studied when the particle crosses a planar boundary between a conducting medium and a vacuum perpendicular to that boundary. This study is based on the relevant exact analytical solutions of Maxwell equations, and the generalized Drude–Lorentz–Sommerfeld formula has been used for the dielectric function of conducting medium in the numerical calculations. The results of our investigation indicated that a charged particle may generate large amplitude oscillations in an electric field at frequencies wherein the dispersion phenomenon is essential and the real part of the conducting material’s dielectric function is negative. The results further revealed that these oscillations are localized at the planar boundary of the conducting medium and a vacuum. The possibility of using this phenomenon to generate electromagnetic radiation at large distances from the surface of a conducting medium of finite size is also discussed.
RESOURCE-EFFICIENT METHODS FOR PREDICTING AND SELECTING HEAT-RESISTANT ALLOYS
Authors: Evdokimov V.B. , Artamonov A.A. , Plotnikov E.V. , Konstantinova N.A.
Published: March 2023

The power plant resource efficiency is largely dependent on heat-resistant alloys and is limited by the standard turbine operating temperature, which is slightly greater than 1000°C. These temperature limits are dependent on the characteristics of the heat-resistant alloys used in power plants. The current research aimed to discover new heat-resistant alloys using computer-based models to simulate the various properties of such materials. The first-principle methods were initially used in this study. These methods can determine the most important properties of alloys with a high degree of accuracy. This study presented an overview of the software used for first-principle simulation. Using RuAl as the demonstration alloy in this study, we provided step-by-step instructions on how to effectively study the properties of the heat-resistant alloys. Using the first-principle methods, the phonon spectrum and density of the phonon states of B2 RuAl were assessed. We use the parameters of the phonon spectrum to calculate the Grüneisen constant, volume coefficient of thermal expansion, Debye temperature, and temperature dependence of the heat capacity to estimate the melting temperature. Based on the RuAl alloy, the bulk moduli of the elasticity and equilibrium values of lattice parameters were calculated. The simulated results showed good agreement with the experimental data. The calculated parameters of RuAl were compared with those of the NiAl heat-resistant alloy. Using these results, we presented a method for selecting an alloy based on the replacement of ruthenium with nickel in the RuAl alloy. Selection was performed by analyzing the bulk modulus of elasticity and the electron structure of the Ru(Ni)Al alloy.
WAYS TO INCREASE THE EFFICIENCY OF SOLAR PANELS OPERATING IN ISOLATED POWER SUPPLY SYSTEMS
Authors: Sorogin A.S. , Khamitov R.N.
Published: March 2023

To cool solar panels in hot season, it is necessary to use special cooling devices. The most optimal way of cooling is the use of liquid cooling, realized by means of a pump. This article provides an overview and evaluation of ways to cool solar panels using various devices. The relevance of the research is caused by the need to reduce the temperature of solar panels in order to increase the output power in the hot season. The main aim of the research is to compare and choose the most optimal way to cool solar panels. Methods: comparative analysis, mathematical modeling in the ANSYS environment. Results. Comparative characteristic of TEM, radiators, fans and liquid cooling is given, an example of cooling a solar panel using liquid cooling to spray a liquid flow of 29 l/min is calculated. The panels will cool down from 45 to 35 °C in 4,7 minutes. For one EasySunSolar solar panel with a capacity of 100 W, costing $100, taking into account electrical work, an additional heat sink module will cost about $50.
Inscripción, desinscripción, intrusión : la etnografía como práctica curatorial
Authors: Andrade X (Xavier)
Published: March 2023

Este artículo discute la práctica artística que conduzco desde 2004 a través de una entidad apócrifa, Full Dollar, como una extensión de mis intereses etnográficos. Full Dollar, de aquí en adelante FD, es definida como una empresa de antropología que interviene en circuitos del arte contemporáneo. Para contextualizarla, brindo una panorámica sobre el cruce de fronteras disciplinarias entre el arte y la antropología como una necesidad imperativa para expandir el poder crítico de miradas etnográficas que operan, por ejemplo, bajo condiciones autoritarias como las de Guayaquil, Ecuador
«Un verdadero templo alzado al saber humano» : Ricardo Palma y la Biblioteca Nacional del Perú
Authors: Guibovich Pérez Pedro
Published: March 2023

«La antigua y rica Biblioteca del Perú fue transportada a Chile. En el último cuarto del siglo XIX han sido los libros, el pan de la inteligencia, considerados como botín de guerra. Hemos retrocedido a los tiempos bárbaros del califa Omar» (Palma, 2005, I, p. 255). De esta forma le expresó el escritor Ricardo Palma a Marcelino Menéndez y Pelayo su estado de ánimo ante el saqueo del que había sido objeto la Biblioteca Nacional del Perú por la oficialidad militar chilena durante la ocupación de Lima entre 1881 y 1883. A continuación, Palma le refirió que el gobierno peruano había decretado la fundación de una nueva biblioteca, además de honrarle con la dirección de la misma. Y agregó: «El país ha acogido con entusiasmo el propósito y, en menos de quince días, he recibido donativos por más de diez mil volúmenes». En el contexto de la posguerra, con un país en ruinas y sin recursos económicos, no extraña que Palma concluyese su epístola haciendo un pedido de libros en términos que lo harían célebre: «Un bibliotecario mendigo se dirige, pues, al ilustre literato, para pedirle la limosna de sus obras, y que avance su caridad hasta solicitar de sus esclarecidos compañeros, en las Academias de la Historia y de la Lengua, contribuyan a la civilizadora fundación encomendada, más que a mis modestas aptitudes, a mi entusiasmo y perseverancia» (Palma, 2005, I, p. 255).
Vicente Quesada, la Biblioteca Pública de Buenos Aires y la construcción de un espacio para la práctica y sociabilidad de los letrados
Authors: Buchbinder Pablo
Published: March 2023

En 1893 Paul Groussac publicó un breve opúsculo en el que sintetizó la historia de la Biblioteca Nacional, en ese entonces bajo su dirección. El relato de Groussac (1967) mostraba dos aspectos salientes de la evolución de la institución. El primero de ellos era la debilidad que había arrastrado el proyecto de conformación de una amplia biblioteca pública para la ciudad de Buenos Aires, al menos hasta la década de 1870. El segundo era el vínculo que unía los orígenes de la biblioteca con las propuestas de extensión de la instrucción popular.
Los intelectuales y sus bibliotecas en el Perú del siglo XX
Authors: Aguirre Carlos
Published: March 2023

Este ensayo es un intento por explorar las relaciones entre el trabajo de los intelectuales peruanos del siglo XX, sus posiciones dentro de las esferas de prestigio y poder institucional y académico, y la formación y peripecias de sus respectivas bibliotecas privadas.
Coropuna y Solimana : los oráculos de Condesuyos
Authors: Ziólkowski Mariusz S.
Published: March 2023

El estudio que se presenta a continuación se realizó dentro del marco del Proyecto Arqueológico Condesuyo, el cual tiene su origen en el Convenio de Cooperación Técnico-Científico firmado en 1996 entre la Universidad de Varsovia (Polonia) y la Universidad Católica Santa María de Arequipa (Perú). El Proyecto abarca la realización conjunta de trabajos de investigación arqueológica en el área de los nevados Coropuna, Solimana y Firura, perteneciente a las provincias de Condesuyos y Castilla, en el departamento de Arequipa, Perú.
Entre guerreros y concertadores : la cultura política de los líderes indígenas de la Amazonia
Authors: Vega Díaz Ismael
Published: March 2023

Este trabajo es una aproximación al proceso de transformación que se viene produciendo en la cultura política de los pueblos indígenas de la Amazonia peruana. Como sabemos, en las últimas décadas los pueblos indígenas han vivido importantes cambios en la organización de su vida social y en la manera cómo se relacionan en la sociedad envolvente. Sin embargo, no estamos ante un proceso homogéneo. No todos los grupos étnicos viven del mismo modo estos cambios, ni están en el mismo momento de este proceso.
The self-esteem of orphaned adolescent girls and its relation to their lifestyles
Authors: Arabiyat Rand , Shihab Pakistan
Published: March 2023

This study aimed to identify lifestyles and their relationship with the self-esteem of female adolescents who lost their mothers. The sample of the study consisted of 58 female adolescents who lost their mothers during the academic year 2019/2020. To achieve the objectives, the study developed two scales; the lifestyles scale and the self-esteem scale. These scales were applied to the participants as a questionnaire. Validity and reliability for both scales were obtained. The results showed that the most common lifestyle among female adolescents who lost their mothers was the socially useful style, and the level of self-esteem among female adolescents who lost their mothers was moderate. The results also showed that there were no statistically significant differences in lifestyle and self-esteem due to the two variables of age at loss and birth order. The results also showed that there was a statistically significant positive correlation between the total score of the self-esteem scale and both dominating style and the socially useful style.
Keywords: Adolescent, lifestyle, orphaned, self-esteem
State Protection Alignment Index as a Measure of Structural Stigma’s Impact on the Mental Health of Sexual and Gender Minorities
Authors: Pharr Jennifer R. , Chien Lung-Chang , Gakh Maxim , Flatt Jason
Published: March 2023

Sexual and gender minority (SGM) populations are vulnerable to health disparities, including worse mental health when compared with cisgender, heterosexual populations. This is in part due to the stigma and discrimination they experience. In this study, we used a novel approach to examine structural-level stigma by determining which categories of statewide law and policy protections for SGM people were associated with mental health outcomes among SGM adults. This was a cross-sectional study using law and policy data compiled by the Human Rights Campaign health data and collected through the Behavioral Risk Factor Surveillance System survey in the United States between January and December of 2019. We applied the weighted quantile sum regression to generate the Protection Alignment Index (PAI) from the 10 SGM categories of laws and policies and evaluated the influence of the PAI on the number of days of poor mental health and a diagnosis of depression. SGM people living in states with a higher SGM PAI, indicating greater protections, had significantly fewer poor mental health days. When the PAI increased one interquartile range (IQR≈0.75), the log of expected poor mental health days significantly decreased −0.04 days (95% CI = −0.08, −0.01;p-value = 0.012). Additionally, the odds of depression was 22% lower (OR = 0.78; 95% CI = 0.62, 0.98;p-value = .033) when the SGM PAI increased one IQR (≈0.77). Findings from this study indicate that whether laws and policies discriminate against or protect SGM people impacts the levels of structural stigma and ultimately mental health. Advocating for more protective laws and policies may be a way to help improve the mental health of SGM populations.
Investigating the effects of different laboratory environments on gifted students’ conceptual knowledge and science process skills
Authors: KAPICI Hasan Ozgur , COŞTU Fatma
Published: March 2023

Instructional technology has been developing rapidly and its impacts can be observed in learning environments. One of the recent technological tools used in science classes is virtual laboratories. This study aims to investigate the effects of virtual laboratories on developing gifted students’ conceptual knowledge and improving science process skills. A total of 60 sixth-grade gifted students were the participants. Half of the students were in the control group, in which hands-on experimentation was followed, and the other 30 sixth-grade students were involved in the experimental group, in which virtual laboratory environments were used. Two different instruments, a multiple-choice conceptual knowledge test, and a science process skills test, were used in this study. The findings indicated that each condition increased their content knowledge and enhanced their science process skills in the study. However, the gifted learners in the virtual laboratory environment performed better than those in the hands-on laboratory environment for both tests. Possible reasons for the findings and some suggestions were also shared in the discussion.
ARTE-EDUCAÇÃO E A SOCIEDADE DE CONTROLE
Authors: Gusmão Roney
Published: March 2023

Neste artigo, o autor apresenta resultados preliminares de pesquisas que tem desenvolvido a respeito dos desafios postos à arte-educação na pós-modernidade. Para tanto, a etapa empírica desta investigação contou com a aplicação de 140 questionários a alunos do Ensino Médio, quando foi possível confrontar o marco teórico em torno da pós-modernidade com os discursos comumente circulados dentre os jovens estudantes. Como resultado, o autor chama atenção para os limites e as potencialidades implicadas na ampla difusão de imagens no contexto contemporâneo, destacando a estética como força (per)formativa ao dispor da educação numa perspectiva pós-moderna.

 

Palavras-chave: Arte-educação; Sociedade de Controle; Pós-modernidade; Poder.
JOÃO SIMÕES LOPES NETO
Authors: Martins Monique
Published: March 2023

A literatura está relacionada às práticas sociais pois as obras literárias retratam situações, comportamentos, sentimentos, e podem servir de instrumentos para compreender melhor o passado e o ambiente em que vivemos. Estudar sobre a vida de escritores de importância histórica e suas obras torna-se uma estratégia para ampliar o interesse pela leitura. Neste sentido, este relato discorre sobre um dos ícones da literatura regional gaúcha: João Simões Lopes Neto; considerado um dos mais expressivos fenômenos literários do início do século passado. Com obras que misturam realidade e ficção, o autor procurou valorizar a história do gaúcho e suas tradições, fazendo uso de uma prosa realista, seca e curta.
QUE ESTAMOS FAZENDO?
Authors: Berselli Marcia , De Medeiros Pereira Diego , Baierle dos Santos Diordinis , Mauro de Melo Junior Sidnei
Published: March 2023

O período de isolamento social, devido a pandemia mundial de Covid-19, exigiu dos artistas da cena a investigação de novos procedimentos de criação que possibilitassem a continuidade de seus trabalhos. Neste texto, pesquisadores do xxxx (XXXX) expõem reflexões acerca do trabalho “O Que Estamos Fazendo?” - processo criativo desenvolvimento em ambiente domiciliar mediante um estrito diálogo com recursos audiovisuais.  Expõe-se o modo como o grupo explorou a abordagem de criação em ciclos - Cycles Repère - desenvolvida por Jacques Lessard, e as Tarefas ou Scores, proposta de trabalho de Anna Halprin. A partir de análise e exposição dos materiais desenvolvidos por um dos atores do trabalho, chega-se à figura do ator-videomaker resultante das funções desempenhadas pelo ator ao longo da criação, bem como dos processos de hibridização entre teatro e tecnologias audiovisuais.
The first encounter with "the black swan": how the pandemic affects the mood of graduates
Authors: Aleksandrova Olga , Proskurina Alexandra , Markov Dmitry
Published: March 2023

The first ILO report against the background of the Covid-19 pandemic names youth among the most anxious groups. Russian sociologists also spoke about this, linking such a reaction with the greenhouse conditions created by Russian families for children. Graduation from a university is a serious life milestone, especially in the context of the pandemic that has required long periods of distance learning and dramatically accelerated the digitalization of the economy. According to the research conducted by the authors, more than two-thirds of students believe that the pandemic has changed our lives forever, and also that in the modern world it is impossible to have one profession for all your life. Medium-term and long-term prospects for specialists with their education do not seem very optimistic to students. But and in the short term, the majority of graduates assess their competitiveness in the labor market as average and foresee high competition for vacancies (or their shortage) and the offer of low wages. For many, the problems of future employment are laid down at the stage of choosing a profession: a significant part goes to study where there are affordable budget places, but poorly understand the essence of the profession and its relevance. Today, half of the graduates would choose another profession and do not plan to work in their specialty. High proportion of those who expected successful employment before the pandemic has noticeably decreased against its background. With regard to employment problems, almost half of the respondents have an internal locus of control, the rest are divided in equal proportions into those who have an external locus of control, or both loci of control are expressed or not expressed. For older students, problems with employment are more often seen as a combination of external factors and their own shortcomings. Among those looking for problems in themselves or both in themselves and in the external environment, there are quite a lot of expecting difficulties in finding a job. Acting within the framework of the "ontological security", young people implement practices that allow them to adapt, but do not reduce uncertainty.
International research and practical conference “Incomes, expenditures and savings of the Russian population: trends and prospects”
Authors: Aleksandrova Olga , Yarasheva Aziza
Published: March 2023

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Sketches for a Scientific Autobiography
Authors: Vizgin Vladimir
Published: March 2023

The article is both scientific autobiography of a professional historian of physics who has worked at the S. I. Vavilov Institute for the History of Science and Technology of the RAS (IHST RAS) for more than half a century, and a reflection of the history of research in the field of the history of physics at the IHST RAS during this time. The author identifies a sequence of turning points associated with his most important works and changes in research topics. His research on the history of the principles of symmetry, the theory of relativity, unified field theories, the social history of Russian physics, and also on the history of the Soviet atomic project are considered. The connection between the history of science and the philosophy of science, which the author taught postgraduate students of the Moscow Institute of Physics and Technology, is also discussed. Particular attention is paid to the author's teachers and his meetings with prominent scientists (science historians, physicists, philosophers), including foreign ones. The article also tells about the scientific and organizational work of the author (leading the sector of physics and mechanics history, related Moscow-wide seminars and seminars on history of the Soviet atomic project), in particular, and about mistakes and missed opportunities in this area. In conclusion, some features and problems of the development of the history of physics and historical and scientific research in general are formulated in the form of “history lessons”.