bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of TEMPO oxidation system on kinetic constants of cotton fibers
Authors: Dai Lu , Dai Hongqi , Yuan Yangchun , Sun Xuan , Zhu Zhengjun
Published: June 2023

The kinetics of the TEMPO-mediated oxidation of cotton fibers were studied. It was revealed that the oxidation reaction of the cotton fibers by TEMPO/NaBr/NaClO system can be approximately described as two pseudo-first-order reaction kinetics that are based on the cellulose microstructure, namely the kinetic processes of the primary wall and the secondary wall. In the concentration range used in this study, the rate constant k was directly proportional to the concentration of TEMPO. As to NaBr, the rate constant was proportional to the concentration in a relatively lower range, while it tended to level off at higher concentration, but the oxidation reaction rate increased with concentration when the concentration was above 1.0 mmol/g. The pH value had a great impact on the oxidation rate; the optimum pH was controlled from 10 to 11. The effect of temperature on the rate constant could be well described by the Arrhenius equation, and the apparent activation energy measured was about 56.66kJ/mol. The X-ray diffraction pattern, which indicates the crystallinity of cotton fibers, was nearly constant during the oxidation.
Improved cellulase production by Aspergillus terreus using oil palm empty fruit bunch fiber as substrate in a stirred tank bioreactor through optimization of the fermentation conditions
Authors: Shahriarinour Mahdi , Ramanan Ramakrishnan Nagasundara , Abdul Wahab Mohd Noor , Mohamad Rosfarizan , Mustafa Shuhaimi , Ariff Arbakariya B.
Published: June 2023

Response surface methodology (RSM) was performed to evaluate the effects of dissolved oxygen tension (DOT) and initial pH on the production of carboxymethyl cellulase (CMCase), filter-paper hydrolase (FPase), and β-glucosidase by Aspergillus terreus in a 2 L stirred tank bioreactor. Delignifiedoil palm empty fruit bunch (OPEFB) fibre was used as the main substrate under submerged fermentation. Growth of A. terreus and the production of three main components of cellulase were optimized by central composite design (CCD) design. Statistical analysis of results showed that the individual terms of these two variables (DOT and pH) had significant effects on growth and the production of all components of cellulase. Maximum growth (13.07 g/L) and cellulase activity (CMCase = 50.33 U/mL, FPase = 2.29 U/mL and β-glucosidase = 15.98 U/ml) were obtained when the DOT and initial culture pH were set at 55% and 5.5, respectively. A high proportion of β-glucosidase to FPase (8:1) in cellulase of A. terreus could be beneficial for efficient hydrolysis of cellulosic materials. The use of OPEFB as a main substrate would reduce the cost of fermentation for the production of cellulase.
Stepwise isothermal fast pyrolysis (SIFP) of biomass. Part 1. SIFP of pine sawdust
Authors: Rivilli Patricia López , Yranzo Gloria I. , Pérez Jorge Daniel
Published: June 2023

Pyrolysis of pine wood sawdust was carried out using stepwise isothermal fast pyrolysis (SIFP), focusing on the search of reaction conditions to obtain chemicals in good yields from biomass. SIFP consists of successive isothermal fast pyrolysis reactions, where solid products obtained in the previous isothermal fast pyrolysis become the substrate of the subsequent reaction at a higher temperature. This article reports results obtained by SIFP of pine sawdust between 200 and 600°C using 100°C intervals under vacuum (0.2 mm), using nitrogen as carrier gas. Both sets of reactions made it possible to obtain most of the compounds that have been previously described in conventional fast pyrolysis experiments; however this system produces a smaller number of chemical compounds in each isothermal FP, making it easier to obtain determined chemicals with industrial or research value. Maximum yield of liquid products occurred at 300°C, giving around 30% of bio-oil, which contained mainly phenols and furan derivatives. Liquid-Liquid extraction led to a rich mixture of phenol derivatives. Results showed that SIFP is an interesting technique to obtain enriched fractions of products derived from biomass pyrolysis.
The effect of cationic surfactants on xerographic toner agglomeration under alkaline pulping condition
Authors: Wang Cuixia , Chin Yungchang F. , Tong Guolin
Published: June 2023

1-octadecanol is known to be a highly effective agglomerating agent for nonimpact-printing toners. However, it was found that some xerographic toners did not agglomerate under alkaline conditions. The effect of alkali on the agglomeration was studied with two different toners, one carrying no surface charge and one carrying a negative charge. The effect of the addition of a cationic surfactant on the agglomeration under neutral and alkaline conditions was then studied using two different cationic surfactants. It was found that both toners agglomerated better under neutral conditions than under alkaline conditions. The toner carrying no surface charge agglomerated much better than the toner carrying a negative charge under either alkaline or neutral conditions. The addition of a cationic surfactant greatly improved the agglomeration of the toner carrying a negative charge but had relatively small effect on that of the toner carrying no surface charge. It is recommended that agglomeration of mixed office waste with 1-octadecanol should be carried out under neutral conditions with the addition of a small amount of a cationic surfactant.
Main and normal cutting forces by machining wood of Pinus sylvestris
Authors: Porankiewicz Bolesław , Axelsson Bengt , Grönlund Anders , Marklund Birger
Published: June 2023

In this work the multi-factor, non-linear dependencies between main (tangential) FC (N) and normal (radial) FN (N) cutting forces and eight machining parameters by sawing simulation of wood of Pinus sylvestris L. were evaluated. The relationships are graphically illustrated and discussed. Evidence of several contradictions was found relative to results from available literature.
Waste of rapeseed from biodiesel production as a potential biosorbent for heavy metal ions
Authors: Tofan Lavinia , Paduraru Carmen , Volf Irina , Toma Ovidiu
Published: June 2023

Rapeseed waste from biodiesel production was explored as a biosorbent for the removal of Cu(II) and Cd(II) ions from aqueous solutions under batch conditions. The optimum value of the initial pH for the sorption of both metal ions was found to be 4.5 to 5. The efficiency of Cu(II) and Cd(II) removal from aqueous solutions varied from 49% to 91% and from 61% to 97%, respectively, by increasing the rapeseed waste dose from 5 to 30 g L-1. According to the evaluation using the Langmuir equation, the monolayer sorption capacity of copper (II) and cadmium (II) ions on rapeseed waste was found to be 15.43 mg g-1 and 21.72 mg g-1, respectively at 293 K. The batch sorption systems under study were thermodynamically characterized by means of parameters such as ΔG, ΔH, and ΔS. The kinetic parameters derived from the pseudo-first-order and pseudo-second-order equations were calculated and compared.
Temperature dependence of yield strength in terms of two components of stochastic shear stress field in glide plane in CrCoNiFeMn alloy
Authors:   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine, M. I. Lugovy , D. G. Verbylo ,   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine, М. P. Brodnikovskyy ,   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine
Published: June 2023

The temperature dependence of the yield strength in the multicomponent CrCoNiFeMn alloy was investigated, using computer modelling and taking into account the short-wave and long-wave components of the shear stress field in the glide plane. The yield strength of a multicomponent alloy in the form of a concentrated solid solution without taking into account grain boundary strengthening is determined by three factors: the periodic lattice potential, the short-wave and long-wave components of the field of stochastic shear stresses in the glide plane, which are created by dissolved atoms. The force barriers resulting from the short-wave component will dominate. Overcoming them by dislocation with the assistance of applied stress and thermal activation will be a critical event to start dislocation movement. Barriers resulting from the periodic lattice potential and the long-wave component will be insignificant against the background of the short-wave component. Their effect on the yield strength can be taken into account by terms that do not depend on temperature. Thermal activation analysis of overcoming barriers resulting from a short-wave component, taking into account the probability of direct and reverse jumps through the barrier, gives the opportunity to describe the temperature dependence of the yield strength of a multicomponent alloy in a wide range of temperatures, including in the region of the high-temperature “plateau”. The dependence of the yield strength calculated in this way for the CrCoNiFeMn alloy correlates well with the corresponding experimental data. Keywords: temperature dependence, multicomponent alloy, glide plane, dislocation.
Effective plastic behavior of porous materials with an inverse opal structure
Authors:   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine, P. Korobko , A. Kuzmov ,   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine,   National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”, M. Shtern ,   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine,   National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”, O. Kirkova ,   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine
Published: June 2023

Based on the theoretical principles of the mechanics of composites, the effective plastic behavior of a porous material with a periodic inverse opal structure under uniaxial loading was studied in detail by means of finite element modeling. The creation of such materials is based on the inversion of pores and skeleton of partially sintered dense packing of polystyrene spheres. Electrodeposited nickel was used as the skeleton of the porous material. According to the macroscopic uniaxial loading or unloading, was finding a stress-strain state at the meso-level. For this, equilibrium equations were solved at the meso-level using special boundary conditions for a periodic unit cell. Such boundary conditions relate the problem of equilibrium at the meso-level with the "effective" deformations of the composite. This made it possible to calculate macroscopic residual strains after a cycle of uniaxial loading and unloading and iteratively find the value of effective stress corresponding to residual strains of 0.2%. In this way, the yield strength of inverse opal for uniaxial loading is calculated. At the same time, as a result of finite-element calculations, the transverse deformations coefficient (plastic Poisson ratio) is determined. This coefficient, in turn, makes it possible to approximate the general plastic behavior of the metamaterial by an elliptic yield curve in the plane of invariants of the stress tensor. Invariants mean average pressure and von Mises stress. These calculations were performing for several cases of the inverse opal structure, both with and without an additional coating. Yield stresses under any type of material loading are very sensitive to porosity. In particular, the application of an additional coating, even with a thickness less than 0,05 of the diameter of the spherical pores (initial polymer particles), causes an increase in the yield strength several times. Keywords: metamaterials, inverse opal, porous plasticity model, micromechanics, theory of plasticity.
Anelasticity and damping capacity of magnesium and Mg—Al alloys under conditions of cyclic high-amplitude loading
Authors:   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine, P. M. Romanko , Yu. M. Podrezov ,   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine, N. M. Marchenko ,   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine, O. M. Malka ,   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine, I. M Maksymchuk ,   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine
Published: June 2023

For Mg—Al alloys with magnesium content from 0 to 9%, measurements of anelastic deformation, damping capacity, and twinning start stresses were carried out. The method of cyclic loading under tension for a wide range of oscillations amplitudes with precision fixation of displacement was used. A method for determination of the start twinning deformation point σ0,002tw under conditions of cyclic loading is proposed, This stress characterizes the beginning of the inverse twinning stage, when the anelastic strain is 2∙10-5. Characteristics of σ0,002tw for technical magnesium and its alloys with aluminum in a wide range of plastic deformation are determined. An insignificant linear increase of σ0,002tw with increasing deformation was established for all Mg—Al alloys. The start twinning deformation point increases with increasing aluminum concentration. For low-alloy alloys with a solid-solution strengthening mechanism, the stress at the beginning of twinning increases insignificantly. For highly alloyed alloys, a significant increase of σ0,002tw stress is observed. It is established that repeated loading within the hysteresis loop to stresses. which is less than the maximum and is not accompanied by additional plastic deformation. If the level of applied stresses during repeated loading reaches the maximum value, the amount of plastic deformation after unloading increases. The addition in εpl gradually decreases with the rise of cycles number. The dependences of inelastic deformation and dissipated energy on the previous deformation degree for all investigated magnesium alloys demonstrate an extreme character. The growth of these characteristics is observed only in the initial part of the load to the residual deformation of 1—2%. With a further increase in deformation, the tendency to anelasticity and the damping capacity decrease. For the dependences dissipatson energy vs amplitude of loob stress, the maximum of dissipation energy is observed under the condition when the stress reaches a critical value, which corresponds to the beginning of prismatic or pyramidal sliding. Keywords: Mg—Al alloys, quasi-static cyclic loading, hysteresis loops, dissipation energy, damping capacity, elasticity, anelasticity, twinning start point.
Research and modeling of thermodynamical properties of melts of Bi—Cu—Eu and Cu—Eu systems
Authors:   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine, V. A. Shevchuk , V. G. Kudin ,   Taras Shevchenko National University of Kyiv, L. O. Romanova ,   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine, M. I. Ivanov ,   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine, V. S. Sudavtsova ,   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine
Published: June 2023

The partial and integral enthalpies of mixing of the melts of the Bi—Cu—Eu system were determined for the first time by the method of calorimetry on three radial sections with a constant ratio of two components: xCu/xEu = 0,3/0,7, xEu/xBi = 0,23/0,77, xEu/xBi = = 0,8/0,2 at T = 1400 ± 1 K. It is shown that the partial and integral enthalpies of mixing of the studied melts are mainly exothermic. Moreover, when adding bismuth to CuхEu1-х melt, the thermal effect of dissolution of the latter increases. This is due to the formation of strong bonds between Bi and Eu. In the other two sections, the opposite happens. Using the literature enthalpies of mixing of melts of the Cu—Eu system, investigated by the method of calorimetry at 1313—1480 K in the entire range of compositions, Gibbs energies, enthalpies and entropies of the formation of melts and intermetallics, their temperature-concentration dependences, and from them — the liquidus curve of the state diagram were calculated of the studied system according to the model of the ideal associated solution. It is shown that the activities of the components in these melts exhibit small negative deviations from ideal solutions and a small amount of associates, especially Eu5Cu, is formed in them. The maximum mole fraction of the EuCu associate reaches a value of 0,09, and the other two (Eu2Cu, EuCu5) — 0,05 and 0,02. From the critically analyzed thermodynamic properties of melts of the Cu—Eu, Bi—Cu and Bi—Eu systems, their reliable data were derived, from which similar parameters for liquid alloys of the ternary system Bi—Cu—Eu were calculated according to various known models. It is shown that the experimental mixing enthalpies of melts of the Bi—Cu—Eu system best agree with those calculated according to the Redlich—Kister—Mujianu model. It was established that ΔHmin = = −61,5 kJ/mol at xBi = 0,5. According to the same model, G, S of these melts were calculated. It was established that Gmin = –40 kJ/mol, and Smin = –18 J/mol•K, the minima of which also fall on the boundary subsystem Bi—Eu, i.e., the main contribution to the interaction energy between different-named atoms of melts of the Bi—Cu—Eu system contribute to the components of this subsystem. Keywords: calorimetry, melts, intermetallics, thermodynamic properties, systems, Bi—Cu—Eu, Cu—Eu, ideal associated solution model, phase equilibria.
Thermodynamic properties of melts of the Cu—In—La system
Authors:   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine, V. S. Sudavtsova , L. O. Romanova ,   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine, V. G. Kudin ,   Taras Shevchenko National University of Kyiv, A. S. Dudnyk ,   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine, N. V. Podeoprigora ,   I. M. Frantsevich Institute for Problems of Materials Science of NAS of Ukraine
Published: June 2023

Partial for the components and integral enthalpies of mixing of the ternary melts of the Cu—In—La system were determined for the first time by the method of calorimetry on five radial sections with a constant ratio of two components:, and (up to xIn = 0,02, 0,14, and 0,42, respectively) and and (up to xCu = 0,15 and 0,2, respectively) at 1220—1450 K. It is shown that when indium 1 is added to the CuxLa1-x melt, the thermal effect of its dissolution increases, which is caused by the formation of strong bonds between In and La. In the other two sections (and), the enthalpies of mixing of ternary melts decrease during dissolution. Using the reliable mixing enthalpies of the melts of the dual systems Cu—In(La) and In—La, similar parameters for liquid alloys of the Cu—In—La system were calculated according to various “geometric” and “analytical” models. It was found that the values calculated by the Redlich—Kister—Mujianu model with the triple contribution –200 agree with the determined enthalpies of mixing of melts of the Cu—In—La system within the limits of experimental errors. It was established that the minimum enthalpy of mixing of melts of the Cu—In—La system falls on the alloy of the In—La subsystem (−43,4 ± 2,1) at xLa = 0,4 at T = 1450 K, i. e., the largest contribution to the enthalpy of mixing of melts of the Cu—In—La system is made by boundary subsystem In—La. The activity of the components in the melts of this system was calculated according to the same model. It is shown that they exhibit small negative deviations from ideal solutions at 1450 K. From these data, G, S of melts of the Cu—In—La system were estimated. It was established that Gmin = –26 kJ/mol, Smin = –12 J/mol∙K, which are attributed to the In0.6La0.4 alloy. Keywords: calorimetry, copper, lanthanum, indium, thermodynamic properties, modeling, mixing enthalpies, activity of components.
Social Interventions in the Family in the Post-COVID Pandemic Period
Authors: Pavlikova Martina , Maturkanič Patrik , Akimjak Amantius , Mazur Slawomir , Timor Tsafi
Published: June 2023

Aim. The main aim of the authors of this study is to indicate the problem areas of individuals and the families during the pandemic and post-pandemic situation which occurred in connection with a deteriorating social and societal situation.
Methods. Using a literary descriptive and deductive method, the authors identify, indicate and analyze not only epidemiological measures and the possibilities of applying social interventions in the individual and in the family, but also draw attention to state measures taken to manage new conditions of family life.
Results. The analysis indicates a broad issue that affects individuals, families, and groups, as well as societal sectors. The authors point to the provision of interventions through social work, which takes into account the basic characteristics of the family. Social intervention therefore becomes an important tool in solving problematic situations of any small or large social group.
Conclusions. The pandemic and post-pandemic situation brought about a number of problematic situations that had to be solved dynamically and, in many cases, through crisis intervention. Forms of assistance to individuals and families brought cohesion and unity, but also brought a number of other concerns reflecting the current adverse societal situation into the wider environment.
The Equal and the More Equal: Pupils' Experiences of School in Lithuania in the late Soviet Era
Authors: Stonkuvienė Irena
Published: June 2023

Aim. The aim of the article is to reveal the experiences and attitudes of pupils who attended schools in the late Soviet era (1960s-1980s) towards the implementation of egalitarianism policies in the schools of the Lithuanian SSR. The analysis of the qualitative research material focuses on the word "felt" in the phrase "We all felt equal then", i.e., not so much on the fixation of social (in)equality by analysing the indicators of social class or economic status, but on the subjective experience of equality as a manifestation of human dignity.
Methods. Following the methodology of oral history, material was collected during 32 in-depth interviews with people who had attended schools in the Lithuanian SSR in the late Soviet era.
Results. Several themes emerged from the analysis of the interviews relating to the expression of egalitarianism in the Soviet school: the social class of the pupils; the economic situation of the parents; and the ability of the parents to have the so-called "blat".
Conclusions. The study revealed that the implementation of the policy of egalitarianism officially declared by the Communist Party in the education system was subject to several reservations. In Soviet Lithuania, just as in the whole society, there were a lot of manifestations of blat, corruption, and favouritism. These were influenced by the positions held by pupils' parents, belonging to the nomenklatura and/or the ability to establish informal contacts. Pupils from rural schools had fewer opportunities to pursue higher education.
The Influence of Family and School in Shaping the Values of Children and Young People in the Theory of Free Time and Pedagogy
Authors: Kralik Roman
Published: June 2023

Aim. The aim of the paper was to point out that the hierarchy of values is considered the most reliable prognostic sign that expresses whether a person can behave in accordance with his environment. The author identifies the causes of the current crisis of value orientations, discusses the influence of family and school on the creation and transformation of values in the lives of young people.
Methods. Through analytical-synthetic and inductive methods, the author identifies the influence of consumer society and family on the creation of value systems of children and youth. It points to the pedagogy of free time and its connection to the theories and functions of free time.
Results. The author provides a summary of theoretical meanings, summaries and theories in the field of value orientation of children and youth, discovered factors that influence the development and formation of value orientation, discovered the share of family, peers and free time in the creation of a value ranking.
Conclusions. Any changes in society brought a wider spectrum of information, freedom of speech, opportunities for social mobility and education, but also deepening of social inequality, deterioration of interpersonal relations, moral relativism and value chaos. Current problems of society's development and their solution also affect the way of life of young people, the process of its quantitative changes, including attitudes to life and value orientation.
Online Temporary Learning Groups in Higher Education – Interactions, Compensation, and Maximisation of Achievements in an Israeli Case Study
Authors: Ben-Shalom Uzi , Hajaj Chen , Davidovitch Nitza , Berger Corinne
Published: June 2023

Thesis. This article provides an analysis of online social interactions in two online Temporary Learning Groups (TLG) and their correlates with both pre-admissions scores and academic achievements.
Concept. The function of Social Networking Systems (SNS) use on academic achievements is most often indirectly assessed through surveying attitudes of students and teachers. Contrary to this approach, we directly assessed the content on a TLG and paired it with objective admission scores and academic achievements.
Results and conclusion. The results reveal that the content of the discussions on the TLGs is practical, immediate, and focuses on the allocation of information required for academic achievements. The users of the TLGs are usually students with lower admission scores and academic achievements. They use these platforms as a compensating mechanism to improve their achievements. In addition, some of the TLG users serve as maximising agents of other students’ achievements. TLGs’ implications for teaching, class-attendance and level of schooling must be recognised by teachers.
Originality. While researchers focus on the presence of SNSs in class and its hampering of schooling by multitasking the effect of TLG activity must also be addressed.
Learning Continuity during COVID-19: An Analysis of the Higher Education Sector of Bangladesh
Authors: Mukherjee Debarshi , Hasan Khandakar Kamrul
Published: June 2023

Aim. This study aims to understand the factors determining university students’ behavioural intentions toward online learning in Bangladesh. Specifically, this study investigates the relationship between performance expectancy (PE), effort expectancy (EE), social influence (SI), facilitating conditions (FC), and behavioural intention (BI). Moreover, this study explores the influence of pandemic fear (PF) as a moderator in the relationship between exogenous and endogenous factors.
Methods. The study is cross-sectional and followed a quantitative research approach with purposive sampling. Data were collected at a single point using a sample size of 578 respondents who studied online during the various phases of lockdown at five public and five private universities in Bangladesh. Regarding multivariate analysis, the Partial Least Squares - Structural Equation Modeling (PLS-SEM) is applied in this study to test the causal relationships in the structural model, as it is considered a second-generation technique.
Results. Statistically, a positive significance was found between PE, EE, SI, and BI in online learning participation. Whereas the FC and the BI exhibited a negative relationship, a positive relationship was found between PE, EE, and the SI on BI. In addition, a moderating role for PF was investigated, and EE and FC were found to influence BI significantly.
Conclusion. This study presents an extended UTAUT model by integrating pandemic fear as the moderator to study students' behavioural intention to adopt an online learning system under a disruptive situation. Practitioners, especially academicians and policymakers, will find this model useful while developing andragogic interventions for the higher education sector in Bangladesh.
Teachers in the Private and Public Spheres: Ethical Orientations in Educational Interactions
Authors: Michvocíková Veronika , Sirotová Mariana , Rubacha Krzysztof , Książek Ewelina
Published: June 2023

Aim. The main aim of the article is a presentation of a comparative study of differences in ethical orientations used by teachers in educational practice in two settings: in private life as parents and in the public sphere, working as teachers.
Methods. First, a hypothesis was proposed to test the observations by Lawrence Kohlberg (1984) and Carol Gilligan (1993) regarding the relative stability of ethical orientations in terms of the ethics of care and justice. To this end, an assumption was made that teachers prefer the former in contacts with their own children (private sphere) while favouring the latter in relationships with students (public sphere). The paired samples t-test confirmed this hypothesis.
Results. Based on the analysis, gender was found not to influence teachers’ ethical orientations in the private sphere; however, it seems to play a part in the public sphere. This ambivalence was revealed in male teachers. Contrary to gender stereotype, in contacts with their own children, they tend to lean towards the ”feminine” ethics of care, but when acting in their public capacity they perpetuate the ‘masculine’ stereotype by following the ethics of justice in their school interactions.
Conclusion. It is worth emphasising the ambiguity of the results obtained and the instability of their interpretations. The actions of the teachers studied do not confirm the thesis about the stability of ethical orientations in educational work and are, therefore, indicative of ambivalence towards the role of gender in this process.
Maternidad desde el encierro: exploración de las condiciones espaciales y arquitectónicas del Módulo Materno Infantil del CAI Vilma Curling en Costa Rica
Authors: Hernández Miranda Andrea
Published: June 2023

Este artículo nace en el marco de un trabajo final de graduación de arquitectura y explora cómo las condiciones espaciales, desde el diseño arquitectónico, pueden impactar la experiencia de los niños y niñas en edades de los cero a los tres años que conviven junto a sus madres privadas de libertad en el Módulo Materno Infantil del Centro de Atención Institucional Vilma Curling Rivera. Se evalúan las condiciones arquitectónicas actuales de este módulo y se estudian las características espaciales que permitirían fortalecer los vínculos maternos, la crianza y la estimulación temprana, disminuyendo las sensaciones de encierro y control. Se concluye que la escala masiva de los espacios penitenciarios, así como las condiciones acústicas, climáticas, sensoriales y de iluminación, ofrecen una vivencia despersonalizada e hiperestimulante. Se identifica la necesidad de descomponer los espacios en nichos más íntimos, con mayor atención a las texturas, materialidades, escala infantil y ergonomía de las superficies y mobiliario que permitan elevar el grado de independencia, autoestima y calidad de vida de sus usuarios.
El encuentro del nosotras y nosotros a partir del lenguaje y la voz. Sobre la teoría y método feminista de María Lugones
Authors: Vargas Vargas Karla
Published: June 2023

Este trabajo sistematiza algunos de los aportes de María Lugones (1944-2020) y se dan a conocer, interpretan y discuten aspectos que permiten comprender la crítica que ella presenta a la teoría y método feministas, a partir del análisis del artículo de Lugones y Elizabeth V. Spelman publicado en 1983, titulado: Have we got a theory for you! Feminist theory, cultural imperialism and the demand for ‘the woman’s voice’, así como Structure/Antistructure and Agency Under Oppression (1990), Playfulness, "World"-Travelling, and Loving Perception (1987), y Purity, Impurity, and Separation (1994). El énfasis de este artículo recae en el examen de la voz y su silenciamiento como forma de opresión hacia las mujeres y otras poblaciones vulnerabilizadas. Lo anterior, se considera una de las simientes de la interseccionalidad que la autora mantiene en sus escritos, como instrumento más abarcador del qué, cómo, quién, para qué, porqué de la opresión, que viven los seres humanos, particularmente las mujeres y que, en esta ocasión, ella relaciona específicamente con el  imperialismo cultural.
Imipenem resistance associated with amino acid alterations of the OprD porin in Pseudomonas aeruginosa clinical isolates
Authors: Nazari Maryam , Ahmadi Hadi , Hosseinzadeh Shahnaz , Sahebkar Amirhossein , Khademi Farzad
Published: June 2023

Globally, the spread of carbapenem-resistant strains has limited treatment options for multidrug-resistant (MDR) Pseudomonas aeruginosa infections. This study aimed to determine the role of point mutations as well as the expression level of the oprD gene in the emergence of imipenem-resistant P. aeruginosa strains isolated from patients referred to Ardabil hospitals. A total of 48 imipenem-resistant clinical isolates of P. aeruginosa collected between June 2019 and January 2022 were used in this study. Detection of the oprD gene and its amino acid alterations was performed using the polymerase chain reaction (PCR) and DNA sequencing techniques. The expression level of the oprD gene in imipenem-resistant strains was determined using the real-time quantitative reverse transcription PCR (RT-PCR) method. All imipenem-resistant P. aeruginosa strains were positive for the oprD gene based on the PCR results, and also five selected isolates indicated one or more amino acid alterations. Detected amino acid alterations in the OprD porin were Ala210Ile, Gln202Glu, Ala189Val, Ala186Pro, Leu170Phe, Leu127Val, Thr115Lys, and Ser103Thr. Based on the RT-PCR results, the oprD gene was downregulated in 79.1% of imipenem-resistant P. aeruginosa strains. However, 20.9% of strains showed overexpression of the oprD gene. Probably, resistance to imipenem in these strains is associated with the presence of carbapenemases, AmpC cephalosporinase, or efflux pumps. Owing to the high prevalence of imipenem-resistant P. aeruginosa strains due to various resistance mechanisms in Ardabil hospitals, the implementation of surveillance programs to reduce the spread of these resistant microorganisms along with rational selection and prescription of antibiotics is recommended.
The Qiṣṣat al-Ḥağğāğ from the University Library in Bratislava
Authors: Gažáková Zuzana
Published: June 2023

This article provides a description, scholarly edition, and translation of an interesting variant of a well-known folk narrative entitledQiṣṣat al-Ḥağğāğabout the famous Umayyad governor al-Ḥajjāj ibn Yūsuf and a young man. The story also appears in various other manuscripts but has rarely been studied. In this case, it is preserved in Ms. TF 136 No. 387 from the Bašagić’s Collection of Islamic Manuscripts, which is housed at the University Library in Bratislava, Slovakia. The variation of the story was also integrated into the Arabian Nights, being a part of the well-known Wortley-Montague manuscript stored in the Bodleian Library in Oxford. To preserve the authentic scribal practices, the presented edition offers the text with all its orthographic and linguistic peculiarities, regardless of how insignificant or incomprehensible they might seem. The edition is accompanied by a translation and explanatory notes. This is probably the first time that a complete text from the Bašagić’s Collection has been thoroughly studied.
Current Electronic Cigarette Use in Adults Aged 18 and Over: United States, 2021
Authors: Kramarow Ellen , Elgaddal Nazik
Published: June 2023

This report uses 2021 National Health Interview Survey data to describe the percentage of adults aged 18 and over who currently use electronic cigarettes by selected socio-demographic characteristics and dual use cigarette smoking status.
COMPARING THE PERFORMANCE OF USING NANOFLUIDS IN TWO DIFFERENT TYPES OF HEAT EXCHANGERS WITH THE SAME HEAT TRANSFER AREA
Authors: Hassaan Amr M.
Published: June 2023

Using multi-wall carbon nanotubes (MWCNTs) based on distilled water with varied volume concentrations, experimental research was conducted. The performance of two distinct heat exchangers with the same heat transfer area was assessed. A tubular heat exchanger (THE) and a shell-and-tube heat exchanger (STHE) with a heat transfer area of 20,000 mm2 were employed. A tubular heat exchanger (HT31) and a shell-and-tube heat exchanger (HT33) are available from Armfield for use with the heat exchange service unit (HT30X). Three volume concentrations of nanomaterials are used to create nanofluids (0.5%, 1%, 2%). While the rate of flow was the same in the heat exchangers, the Reynolds number of the flow inside the tube ranged from 1600 to 7800 for THE and from 2500 to 12,500 for STHE due to different inside diameters. The measured variables determine the coefficient of heat transfer, friction factor, Nusselt number, and effectiveness. The heat transfer coefficient in both heat exchangers was boosted with increasing MWCNT content, according to the experimental data. Because of the nanoparticle concentration, the heat transfer coefficient of STHE is 7-43% greater than that of THE. With the increase of nanofluid concentration, the Nusselt numbers were enhanced for the two heat exchangers. The increase in the Nu number for THE is higher than in its value for STHE within a range of 28.5-40%. Correlations between the Reynolds number and MWCNT volume concentration are proposed for each heat exchanger to compute the Nusselt number and friction factor. The results of the current study have been compared with previous studies and acceptable agreement can be found.
Improving capillary water absorption of high-volume fly ash mortar by curing temperature and limestone addition
Authors: Di Yunfei , Zhao Haitao , Li Xiaoxiong , Chen Yun , Shi Zhenqing , Man Xiaolei
Published: June 2023

The effects of curing temperature (20°C, 40°C and 60°C) and the addition of limestone powder (LP) (6% and 12%) on the capillary water absorption (CWA) of high-volume fly ash (HVFA) cement mortar were investigated. X-ray diffraction analysis and tests for chemically bound water content (CBWC), compressive strength and porosity were also conducted. It was found that, for a fly ash (FA) content exceeding 30%, the CWA increased significantly. When the FA content was 50%, the curing temperature was raised to 40°C or the LP content was 12%, the CBWC increased greatly. Increasing the curing temperature or adding LP increased the compressive strength and decreased the porosity of the HVFA cement mortar. Prediction of the water penetration depth in the HVFA cement mortar was consistent with the CWA results. The results of this work indicate that an increase in curing temperature or the addition of LP could be an efficient way of improving the CWA performance of HVFA cement mortar.
Procurement and contracting for climate change data and digital solutions
Authors: Friel Anne-Marie , Marfé Mark , Martin Chris , Harding Rebecca
Published: June 2023

The current constraints on skills and knowledge across the infrastructure sector on how to set up, structure and procure digital solutions at each stage of the asset life cycle need to be rapidly overcome to allow climate change targets to be achieved. Digital solutions and data sharing must be given a high priority, with operating models developed and funded as part of the overall resourcing, procurement and contracting process for infrastructure assets. This paper summarises some of the practical, structural and legal considerations that need to be overcome to enable digital solutions – particularly building information modelling and digital twins – to be successfully implemented to support infrastructure climate change targets.
Application of ecological energy-saving materials in intelligent building decoration
Authors: He Hongtao , Niu Tianxin , Ding Aijuan , Ren Hongjie , Zhang Limin
Published: June 2023

People’s demand for living space is becoming higher. However, when people carry out interior decoration, they neglect the choice of environmental protection materials and various pollution problems. To improve people’s decoration and housing conditions, this paper studies the application of ecological energy-saving materials in intelligent building decoration. Firstly, the application status of intelligent building decoration materials is described. Then, the advantages of ecological energy-saving decorative materials are analysed. Finally, the application of the materials in wall and floor decoration was studied, and the sound insulation properties were tested. The comprehensive analysis shows that the range of application prospects of ecological energy-saving materials in intelligent building decoration is wide. According to the test results, the materials investigated in the study exhibit effective characteristics for green building, indicating that energy-saving materials have a broad range of application prospects in this field.
Microfungi species observed on various weed species in the Yüksekova Basin, Türkiye
Authors: Sırrı Mesut , Özaslan Cumali
Published: June 2023

Studies on biological control for the sustainable management of weeds that exert serious ecological, economic, and human health problems are attracting increasing attention. Detection of potential biological control agents (pests, pathogens, etc.) on target weed species is the first step in the biological control program. This study aimed to determine the microfungi species found on noxious weed species in the Yüksekova basin situated in Hakkari province, Türkiye. Continued traditional agricultural practices, minimum or no use of pesticides and fertilizers, and better protection of natural flora/fauna compared to other parts of Türkiye were reasons for the selection of the basin in the current study. Field surveys were carried out in different periods during 2020 and 2021. A total of 101 microfungi species were recorded on 79 weed species belonging to 29 families in the basin. The most common fungi species in the basin were in genera Puccinia (29 species), Alternaria (18 species), Uromyces (14 species), and Curvularia (4 species). Weed hosts of the above-mentioned fungi species mostly belonged to Asteraceae (20 species), Fabaceae (7 species), Poaceae (7 species), and Lamiaceae (6 species) families. While 84 microfungi species were recorded on a single host, and the remaining 17 were found on more than one weed species. It has been observed that Puccinia cyani (Schleich.) Pass., Puccinia chondrillina Bub & Syd., and Uromyces polygoni-aviculariae (Pers.) P. Karsten significantly inhibited the growth and development of their host weed species (Centaurea spp., Chondrilla juncea L., and Polygonum aviculare L.) and were able to suppress the populations of the weeds in the fields. The results revealed that it would be beneficial to review the recorded pathogens in terms of biological activity and to carry out detailed field studies in the region.
Preparation of rhodium concentrate from gold cementate
Authors: Zelyakh Ya. D. , Voinkov R. S. , Timofeev K. L. , Maltsev G. I.
Published: June 2023

This article describes studies on improving reprocessing technology gold production cementate (GPC) formed in refining section of chemical metallurgical shop at JSC Uralelektromed, in order to increase the extraction rate of targeted metals into marketable products, diversification of production, achievement of economic effect due to increasing content of precious metals (PM) in individual concentrates. The optimization of GPC reprocessing technology includes intensification of leaching of initial material and filtration of produced pulp, in order to increase the extraction of gold and platinum group metals (PGM) into solution and decrease the circulated PM. This would allow individual products (crude PM) to be obtained with minimum material loss and labor consumption. It is possible to increase rhodium content in concentrate and to reduce its circulation by preliminary oxidating annealing at the temperature above 500 °C. At this temperature hardly soluble trioxide Rh2O3 is formed on rhodium surface, insoluble in aqua regia, thus allowing it to deposit in the form of individual product. The influence of temperature and composition of gaseous phase was established upon oxidizing annealing of initial raw stuff (t = 500÷750 °C) on the composition of rhodium trioxide concentrate (15÷45 % Rh2O3). Reprocessing flowchart of gold production cementate was developed and tested on commercial scale, allowing for the simultaneous production of several products: deposited gold (Au ≥ 98 %), deposited silver (Ag ≥ 98 %), PGM concentrate (Pt ≥ 45 % and Pd ≥ 15 %), rhodium concentrate (Rh = 15÷45 %).
The efficiency of multithreaded computing in casting simulation software
Authors: Bazhenov V. E. , Koltygin A. V. , Nikitina A. A. , Belov V. D. , Lazarev E. A.
Published: June 2023

The utilization of computer simulation software for casting process simulation is becoming essential in the advancement of casting technology in aviation and other high-tech engineering fields. With the increase in the number of computational cores in modern CPUs, the use of multi-threaded computations is becoming increasingly relevant. In this study, the efficiency of multi-threaded computations in modeling casting processes was evaluated using finite element method casting simulation software ProCast and PoligonSoft, which utilize parallel computing architectures with distributed (DMP) and shared (SMP) memory, respectively. Computations were performed on Intel and AMD-based computers, varying the number of computational threads from 4 to 32. The calculation efficiency was evaluated by measuring the calculation speed increase in the filling and solidification of GP25 castings made of ML10 alloy, as well as the complex task of filling and solidification modeling nickel superalloy casing castings with radiation heat transfer simulation. The results indicate that the minimum computation time in ProCast software is observed when using 16 computational threads. This pattern holds true for both computing systems (Intel and AMD processors), and increasing the number of threads beyond this point does not make a practical difference. The performance decrease in this scenario can be attributed to the low-performance energy-efficient cores in systems based on Intel processors or the decrease in core frequency and full loading of physical cores in systems based on AMD processors. Multi-threading the modeling task in PoligonSoft software is less efficient than in ProCast, which is a result of the shared-memory architecture used in PoligonSoft. Despite the significant difference in parallel efficiency, the task of GP25 casting solidification in both PoligonSoft and ProCast is solved in a time close enough to be considered sufficient.
Porous wax patterns for high-precision investment casting
Authors: Zhilin S. G. , Bogdanova N. A. , Komarov O. N.
Published: June 2023

Aerospace, manufacturing, and shipbuilding industries strive to enhance their competitiveness by optimizing material utilization and improving production processes. The investment casting process offers the capability to fabricate intricate and precise components using a diverse range of alloys. However, this method is not without its drawbacks, including high manufacturing costs and a significant rate of defective castings, which can reach up to 30 %. These defects primarily arise from the stresses imposed on the wax patterns and ceramic molds, leading to their distortion. To address this issue, efforts have been made to reduce stress by employing compacted wax powders for the production of investment patterns. However, stress relaxation in the wax patterns remains a concern as it can result in elastic deformation of the compacted material and subsequent alterations in the final product dimensions. To mitigate this issue, a series of tests were conducted with the objective of studying stress relaxation under constant compression strain, as described by the Kohlrausch equation. The obtained results provide valuable insights that enable the prediction of the ultimate dimensions of patterns created using different grades of wax.