bluuebunny/crossref_metadata_2025 huggingface dataset:
Immunomodulatory effects of thymol and cinnamaldehyde in chicken cell lines
Authors: Shen C. , Christensen L.G. , Bak S.Y. , Christensen N. , Kragh K.
Published: May 2020

Thymol and cinnamaldehyde are phytogenic feed additives that have been developed to improve gut health, immunity and growth performance in poultry and swine. This study evaluated the immune modulating effects of a thymol and cinnamaldehyde blend (TCB) in the intestinal system of poultryin vitro, using two chicken cell lines, LMH (liver cell line) which has been used to mimic epithelial cell responses, and HD-11 (monocyte/macrophage-like). Cells with high viability (>95%) from established cell lines were cultured in the presence of TCB at concentrations ranging from 1 ng/ml to 100 ng/ml. The viability, transepithelial electrical resistance (TEER) and phagocytic capacity of co-cultured LMH cells, with or without stimulation with lipopolysaccharide (LPS), was subsequently evaluated. The expression of cytokines, chemokines and pattern recognition receptors by HD-11 monocytes/macrophages was measured by RT-PCR and by proteomic analysis. TCB was well tolerated by both cell lines (cell viability >90% after co-culture with TCB at 100 ng/ml for 48 h with or without LPS). Epithelial integrity of LMH cells (as assessed by TEER) was increased by TCB (10 ng/ml) after 4 h incubation, versus untreated controls, and phagocytic capacity of HD-11 cells was increased, in a dose-dependent manner (P<0.05). In HD-11 cells, TCB (10 ng/ml) downregulated the relative expression of pro-inflammatory cytokines interleukin (IL)-1β, IL-6, IL-8 and the transcription factor cyclooxygenase-2 and upregulated expression of anti-inflammatory IL-10, versus untreated controls (P<0.05). In summary, under the tested conditions, TCB enhanced the epithelial barrier integrity of poultry hepatocytes, increased phagocytic activity and production of anti-inflammatory cytokines by monocytes and macrophages. These results indicated how supplementing TCB in poultry diets can increase bird performance, by increasingin vivo cell membrane integrity (especially important in the gut) and assisting in immune responses, which can liberate energy for growth.
Exploration of consumer acceptance of insects as food in Poland
Authors: Zielińska E. , Zieliński D. , Karaś M. , Jakubczyk A.
Published: May 2020

In the last decade, increasing attention has been focused on entomophagy in Europe. However, Western societies rarely experience insects as a food source. Depending on the country, the approach to entomophagy is variables. This study was performed to assess the perception of entomophagy in the Polish population and comparison with other European societies. An online survey was conducted with a final sample of 419 participants. Several variables were established, and their influence on the acceptance of insect was analysed by applying the Chi-square test of independence. We found that the respondents had limited knowledge about entomophagy; hence, willingness to eat insects is limited by unawareness and neophobia. The attitude towards insects is a strong predictor of the readiness to eat insects and buy insect-based products. The results have shown that processed insect products can increase consumers’ willingness to buy insect-based products. It should be noted that almost 60% of the 15.51% of the respondents who had eaten insects previously rated the insect taste as good and very good. We conclude that higher awareness of entomophagy is required to accept insects as food besides the willingness to try. Moreover, the future of insect consumption depends on the sensory characteristics (appearance, smell, taste) of insect-based products; hence, food industry should focus on processed foods with insect based food ingredients to make them familiar to consumers.
Le commerce à Bruxelles : réconcilier l’urbain avec un secteur en reconfiguration
Authors: Wayens Benjamin , Debroux Tatiana , Godart Pernelle , Mahieu Céline , Strale Mathieu , d'Ieteren Emmanuel
Published: May 2020

La Région de Bruxelles-Capitale comptait en 2017 20 700 points de vente de biens et de services, par lesquels transitent 87 % des dépenses effectuées par les Bruxellois. Ce commerce de détail offre environ 9 % de l’emploi régional. Cette note de synthèse fait le point des connaissances sur la distribution à Bruxelles, un secteur économique indispensable, mais complexe à appréhender du fait de sa diversité et traversé par de profondes évolutions de la consommation, de l’environnement urbain et de l’organisation interne du métier. Après avoir esquissé le cadre de l’analyse en définissant le commerce au travers de ses fonctions, de ses formes et de ses acteurs, les auteurs dressent plusieurs constats associés à des dynamiques majeures du secteur (transformation de l’offre, de la demande et évolution de la régulation publique, notamment). La troisième partie de la note répond à ces constats par l’identification d’enjeux clairs dont la prise en compte par le secteur, soutenu par les autorités publiques, pourrait réconcilier le commerce et l’espace urbain.
Data Augmentation Using GANs for 3D Applications
Authors: Maniadis Ioannis , Solachidis Vassilis , Vretos Nicholas , Daras Petros
Published: May 2020

Modern deep learning techniques have proven that they have the capacity to be successful in a wide area of domains and tasks, including applications related to 3D and 2D images. However, their quality depends on the quality and quantity of the data with which models are trained. As the capacity of deep learning models increases, data availability becomes the most significant. To counter this issue, various techniques are utilized, including data augmentation, which refers to the practice of expanding the original dataset with artificially created samples. One approach that has been found is the generative adversarial networks (GANs), which, unlike other domain-agnostic transformation-based methods, can produce diverse samples that belong to a given data distribution. Taking advantage of this property, a multitude of GAN architectures has been leveraged for data augmentation applications. The subject of this chapter is to review and organize implementations of this approach on 3D and 2D imagery, examine the methods that were used, and survey the areas in which they were applied.
Review on Various Machine Learning and Deep Learning Techniques for Prediction and Classification of Quotidian Datasets
Authors: Lal Anisha M. , Reddy B. Koushik , D. Aju
Published: May 2020

Machine learning can be defined as the ability of a computer to learn and solve a problem without being explicitly coded. The efficiency of the program increases with experience through the task specified. In traditional programming, the program and the input are specified to get the output, but in the case of machine learning, the targets and predictors are provided to the algorithm make the process trained. This chapter focuses on various machine learning techniques and their performance with commonly used datasets. A supervised learning algorithm consists of a target variable that is to be predicted from a given set of predictors. Using these established targets is a function that plots targets to a given set of predictors. The training process allows the system to train the unknown data and continues until the model achieves a desired level of accuracy on the training data. The supervised methods can be usually categorized as classification and regression. This chapter discourses some of the popular supervised machine learning algorithms and their performances using quotidian datasets. This chapter also discusses some of the non-linear regression techniques and some insights on deep learning with respect to object recognition.
The Individual Care Plan as Electronic Health Record
Authors: Lopes Manuel José , Fonseca César , Barbosa Patrícia
Published: May 2020

The idea of the need for healthcare planning, whether in the individual or collective dimensions, is consensual among all health professionals. Despite this consensus, as well as a discourse that values teamwork, planning focused on health professionals has prevailed. Due to the current circumstances, particularly those resulting from changes in the epidemiological profile of the population, a new way of planning individual healthcare is required that must meet the following criteria: be of an individual nature, integrate the active participation of the citizen/family caregiver, be focused on care in the course of life, safeguard interdisciplinarity, assist in decision making about care, and be able to record decisions about care.
Resilient Software Architecture Platform for the Individual Care Plan
Authors: Mendes David José Murteira , Lopes Manuel José , García-Alonso José Manuel , Santos Jorge , Sousa Luís Manuel Mota
Published: May 2020

The individual care plan (ICP) is a metamorphic being. The only steady reality that it maintains is its final objective, stated and explained in the previous chapter where the ICP is thoroughly introduced and debated. It is a fantastic beast, better described as a system of systems that is severely polymorphic due to its coverage both in level of care as well as sources of data to handle. Patient monitoring generates large volumes of data. There is the evident need of an advanced approach that can deal with these huge amounts of healthcare data extracted from various sources such as the wearable sensors, medical, and nursing records that are currently called big data. The purpose of this chapter is to introduce and discuss the software platform that is adequate to develop and deploy the system paying attention to the needs of high-availability, sensitive information security; service-level agreements for multiple healthcare interoperability; law and ruling conformance; as well as other technical and ethical aspects.
Attitudes of Society Towards People With Neurodevelopmental Disorders
Authors: Khanna Pallavi
Published: May 2020

Social acceptance and inclusion of people with neuro-developmental disorders is challenging. Though each human being is unique, the world population can be segregated into two groups: neuro-typical and neuro-diverse people who have conditions such as autism spectrum disorder, cerebral palsy, learning disabilities, ADHD, and several others. The neuro-typical population claims to be accepting of the neuro-diverse population, but some case studies show that it may sadly not be true. Life can be bewildering and confusing for a person with disabilities. Dealing with so many aspects can be daunting and frustrating for them and their families. Social attitude is a significant factor as the Pwd navigates the harsh world of discrimination and social abandonment and faces barriers where support, guidance, and services are required. Many go through painful journeys and come out stronger and wiser, but bitter as well. Others have had better support. This chapter is a collection of experiences of some Pwd and their families and a list of solutions to the different challenges they encounter.
Enhancing Life Skills of Children and Adolescents With Autism Spectrum Disorder and Intellectual Disabilities Through Technological Supports
Authors: Stasolla Fabrizio , Passaro Anna
Published: May 2020

This chapter provides the reader with the newest empirical contributions available on the use of assistive technology-based interventions aimed at enhancing life skills of children and adolescents with autism spectrum disorders and developmental or intellectual disabilities. A selective overview along the last decade was carried out. Eighteen studies were reviewed, and 155 participants were involved. Five main categories of studies were identified, namely (1) emotional regulation, (2) communication skills, (3) academic performance, (4) social inclusion, and (5) challenging behavior. Results were fairly positive, although occasional failures occurred. Clinical, educational, psychological, and rehabilitative implications of the findings were critically discussed. Some useful guidelines for future research and practice were highlighted.
21st Century Education for Special Needs Students
Authors: Dhir Harpreet Kaur
Published: May 2020

Education is a human right—including students who have conditions requiring special education services. The purpose of this chapter is to promote inclusive education for students with learning disabilities due to diagnoses such as attention deficit hyperactivity disorder, autism, and more. A literature review includes a discussion pertaining to the elements of appropriate teaching methods compatible with developing 21st-century competencies for general education and special education students within the same classroom setting. Relative to employing strategies of differentiation and scaffolding while increasing cognition through experience-based lessons, this chapter provides examples from the author's classroom instructional plans. The content through action (CTA) method is presented as an ideal approach conducive to integrating 21st-century competencies through experiential lessons to teach the required content to students of various abilities. The chapter ends with recommendations on creating systemic change through building a support system at an organizational level.
A Review of Supportive Computational Approaches for Neurological Disorder Identification
Authors: Meedeniya Dulani , Rubasinghe Iresha
Published: May 2020

At present there is a growth of physical symptoms with psychological overlays, resulting in neurodevelopment disorders, where both psychiatrist and medical specialties work in collaboration to provide optimal care for the patients. Disorders such as autism spectrum disorder, attention-deficit hyperactivity disorder, Down syndrome, cerebral palsy, sickle cell disease, and Alzheimer disease are more prevalent. These may have a genetic influence and give certain behavioural disturbances due to associated medical issues. The symptoms are observable in early childhood, and they may consist of comorbid medical disorders. This chapter addresses recent studies together with the applied techniques in this context. Further, this chapter shows the limitations, challenges in current practices, and possible future research directions.
Big Data-Based System
Authors: Wadhera Tanu , Kakkar Deepti
Published: May 2020

In the health domain, the move of generating big data is opening new methodologies in detection as well as prediction of various diseases and disorders. The first phase of the present chapter has provided insights into the role of big data analytics in the detection of one such neuro-disorder, that is, autism spectrum disorder (ASD). The data lake concept has provided a direction to resolve the issue by providing a common platform for storing tremendous amount of data in all formats (structured, unstructured, or raw). However, if the entire data have potential value, the data lakes need to be strategically designed as otherwise it can lead to data swamps. Therefore, in the second phase, data lake based on Hadoop architecture and Apache Spark engine has been provided for the analysis of the health data. The proposed system has resolved the data storage issue, management, and analytics on a single platform. Hence, the novelty of the chapter is that it is pointing towards the faster exploration as well as management of data so that the timely generation of hypothesis can help in analyzing ASD.
How to Deal With Corporations' Complicatedness
Authors: Luiz Manuel
Published: May 2020

This chapter discussed how companies in the 21st century need to simplify their internal processes in order to become competitive in the external market and foster productivity. The authors focus the discussion in Brazil, an emerging economy that suffers the effect of globalization (as much as other developed economies) but, at the same time, is plagued by structural factors that hinder the country's competitiveness, a concept that is referred to as “Brazil cost.” The chapter suggests a possible framework to address the need for simplifying the company's internal context and driving performance in order to fight the growing external complexity.
Housing Consumption
Authors: Marques Joao Lourenço , Batista Paulo , Castro Eduardo Anselmo , Bhattacharjee Arnab
Published: May 2020

Housing is more than a living space; it represents a social status capable of promoting several forms and levels of socialization and segregation. Housing is characterized by a set of attributes and functions that are valued differently, in which the consumption of “good housing” is made considering the preferences of their attributes, perceived tangibly/intangibly by the consumers. The reciprocal relation between housing and space, and the lack of structured information capable of apprising the key drivers of such dimensions increase the complexity of understanding the rational mechanisms of evaluating the real housing value. Despite the challenges associated with the modelling of housing markets, urban studies and spatial econometric literature provide a broad (but unfinished) theoretical framework and practical tools that are able to describe, understand, and predict households' housing consumption. Thus, the aim of this chapter is to present concepts and techniques to rationally capture individual and collective housing preferences, and the way in which they interact.
Alpaca Meat
Authors: Caceres Yezelia Danira , Gonzalez Sara , Medina Juan Rivera
Published: May 2020

The chapter analyses alpaca (Vicugna pacos) meat production and consumption in Peru. The analysis highlights what affects alpaca meat consumption, drawing from exploratory studies in the Andean high zone of Arequipa, Puno, and Cusco. The reasons that are behind alpaca meat consumption decisions are anthropological aspects related to historical and cultural processes, as well as the commercial channels and the presentation of the product. In this sense, the authors link the theoretical approach on consumption, emphasizing the influence of the consumer in the market and vice versa. Nevertheless, it is interesting to note that even in the current conditions of the market there is a growth in the demand for alpaca meat resulting from the increase in tourism flows, not only of foreigners but also Peruvians.
The Portuguese Luxury Wine Market
Authors: Metello de Nápoles Nuno , Nobre Helena , Meneses Raquel
Published: May 2020

Wine has been a part of human history for thousands of years, serving both social and religious roles. Just a few centuries ago, it became possible to store wine in good conditions, allowing it to be bottled and aged, which created a luxury product, consumed as a token of prestige. This study aimed to analyse wine brand managers' perceptions on the motivations behind luxury wine consumption. Given the exploratory nature of the study, eight interviews with Portuguese luxury wine producers and distributors' managers have been undertaken. The content analysis of the interviews seems to indicate that, overall, there is a strong understanding of the consumers' motivations. Yet, there are certain more specific aspects with the potential to be explored in order to raise the efficiency of the strategies being employed.
The Consumer Role for Sustainable Development
Authors: Yildirim Seda
Published: May 2020

The term sustainable consumption is not only a behavior type in marketing and a just consumption behavior, it is more than this. Sustainable or responsible consumption behavior can change the world. Sustainable consumption concept has been investigated widely in the literature and factors that effecting sustainable consumption or being a green consumer has been investigated recently, too. But the relationship between sustainable development and consumer behavior isn't investigated sufficiently. After 2030 Sustainable Development Goals set up, responsibilities and roles have been an important issue to achieve sustainable development in the long term. In this point, this study aims to investigate the consumer role for sustainable development goals through sustainable consumption patterns and trends.
Shifting Towards English Medium Instruction in Higher Education
Authors: Horbacauskiene Jolita , Jaleniauskiene Evelina
Published: May 2020

In higher education (HE), the emerging global phenomenon of English medium instruction (EMI) has brought huge opportunities for both students and teaching staff as universities are increasing the number of English-medium programmes. A number of studies have been conducted to explore EMI policies and practices, implications for pedagogy, as well as challenges for educators and students, including learners' academic skills, learning styles, level of content knowledge, academic practices, and varying ethical standards. Some issues under analysis are considered to be the main problematic questions faced in multilingual and multicultural classrooms. As noted by Dearden, the change in the learning and teaching language may deeply affect not only students but teachers as well. The current study seeks to answer the research questions of how university teachers conceptualize EMI and what possibilities and challenges this practice offers.
Teaching Professional Foreign Language Discourse via IT Tools
Authors: Shulgina Elena
Published: May 2020

The chapter “Teaching Professional Foreign Language Discourse via IT Tools: Through the Example of WebQuest Technology” is devoted to the description of the didactic tools development based on the Internet technologies (IT) and the integration of the problem-based learning into the educational process for the formation of professional foreign language discourse in non-linguistic students. The author presents the experience of using IT, in particular the web-quest technology, in practice for the purpose of creating a professional foreign language discourse that allows students to master professional knowledge and develop relevant skills in the field of professional communication. In the chapter the web-quest technology is considered to be one of the most appropriate IT tools for the successful formation of professional foreign language discourse in students with non-linguistic major, since the format of the technology allows the teacher to manage the student work at all stages. In addition, the integration of the web-quest technology into the educational process solves one of the key tasks of modern education, i.e. the increase in the volume of students' independent work, due to which the process of metacognition develops the self-regulation of the personality. The chapter pays great attention to the historiography of problem-based learning from the very origins to modern times, its transformation and types, which depend on the didactic goals being set during the learning process. At the end of the chapter, the author presents the experience of technology integration in the pedagogical process and the results of the experiment.
Writing Bees, Wikis, Problem-Based Learning, and Assessment
Authors: Howard Lyz
Published: May 2020

This chapter introduces a case study to explore the pedagogical re-design of an online module using online discussions as the focus for learning. A longitudinal and development module assessment was threaded through three phases of learning: 1) writing bees, 2) WIKI (what I know is), and 3) problem-based learning (PBL). Each phase of learning is explained using evidence to support its development, and a critique of the benefits and limitations of learning this way is included. An evaluation of the re-designed module is included, demonstrating although at times the online discussion and writing activities were challenging that on the whole, students enjoyed learning in this way. This chapter concludes by claiming that the pedagogical design of learning using online discussions should be engaging, interactive, collaborative, and fully supported at every stage of the learners' journey and recommends further research in the theory of communities of practice to inform such pedagogical design.
Gamifying Discussion Forums
Authors: Nagurney Alexander , Smith Patrick A. , Read Michelle Fulks , Jensen Ann Evans , Morel Gwendolyn M. , Butcher Tamarin
Published: May 2020

This study examines the effect of gamifying and adding problem-solving aspects to discussion prompts in online courses with the goal of increasing the quantity and quality of student work. It was also a goal to foster motivation, engagement, and critical thinking skills. Results show an increase in the number of posts, the quality of posts as evaluated by the instructor, and student satisfaction with the overall course judged by responses to a survey administered at the end of the course. A number of recommendations are made, including furthering the use of student choice in how coursework is completed, promoting teamwork, and using incentives to increase student engagement.
Private Interactions in Online Discussions
Authors: Wilton Lesley , Khan Rubaina , Brett Clare , Alexander Paul C.
Published: May 2020

Private discussion entries (called “notes” in this chapter) provide opportunities for instructors to engage with students for social and cognitive support in discussion-based online learning environments. Situated within discussion threads, embedded private communication allows for personalized engagement with students to support learning through in-place feedback, redirection, and encouragement. Nine themes of the affordances of private notes were identified through the collection and analysis of quantitative and qualitative data gathered from four instructors and the activities of 278 students in 11 online graduate education courses. The benefits of private, in-place interactions identified by the instructors include encouraging authentic participation, building trust and social presence, redirecting conversation, providing advice about learning online, and more. A discussion of the importance of in-place private communications in online learning for providing feedback, reassurance, and guidance is supported by examples and followed by suggestions for future research.
Two Case Studies of Online Discussion Use in Computer Science Education
Authors: Akcayir Gokce , Chen Zhaorui , Epp Carrie Demmans , Pandeliev Velian , Munteanu Cosmin
Published: May 2020

In this chapter, two cases that include computer science (CS) instructors' integration of an online discussion platform (Piazza) into their courses were examined. More specifically, the instructors' perspectives and role in these cases were explored to gain insight that might enable further improvements. Employing a mixed methods research design, these cases were investigated with text mining and qualitative data analysis techniques with regard to instructors' integration strategies and students' reactions to them. The results of the study showed that among these cases, one entailed a deep integration (Case 1) and the other a shallow one (Case 2). Instructors' presence and guidance through their posting behaviors had a bigger effect than the nature of the course content. Additionally, TA support in online discussions helped address the limitations of the asynchronous discussion when the TAs had the maturity to only respond to questions for which they were adequately prepared.
A Dragon on the River of Painted Birds
Authors: Pérez Bañasco Martín
Published: May 2020

China is a country with a history that spans more than 5000 years, a civilization that has maintained its customs and art throughout that period, and a nation that is known to the world as the “Dragon of Asia.” Uruguay is a small country in South America with a similarly rich cultural background, whose name, in the indigenous language of the Guaraní people, means the “River of the Painted Birds.” Uruguay has a comparatively small history of only 200 years, but it is a nation defined by the diversity of its population and their experiences – from the indigenous people to the colonizers and immigrants. Uruguay is also a land of revolutions, marked by the search for social equality and freedom.
Between Tradition and Innovation
Authors: Armie Madalina
Published: May 2020

Numerous publications try to encompass the rhythm of change in classroom and attempt to guide foreign language teachers. This chapter describes how using the methodology of short stories and storytelling to teach ESL/ELT to children opens new ways of renewal, enhances the quality of teaching, breaks routine, and brings novelty to the monotony of lessons. A second purpose of the following pages is to present the advantages of teaching English to children using storytelling while trying to build a bridge between theory and the applications of stories in the classroom. To accomplish this goal, the chapter explores some instruments that offer visual support, and which maximize the impact of short stories' narration. These elements transform the act itself into a multilayered and multimodal experience with numerous benefits, such as the improvement of literacy, enhancement of imagination, the development of children's cultural awareness, the broadening of their general knowledge, the fostering of personal growth, the fomentation of group interaction and collaboration.
Patterns of Fracture Initiation in Metallic Materials with a Heterogeneous Structure under Dynamic Cyclic Loading
Authors: Kudryakov Oleg V. , Varavka Valery N. , Morozkin Igor S.
Published: May 2020

The process of nucleation of fatigue defects in metal alloys with different structural morphology is considered. A physical model was built, calculation expressions were presented, a numerical experiment was performed to determine the moment of nucleation of the critical-size defect in Fe-based alloys during high-speed droplet impacts. The physical model is based on the theory of dislocations. It is shown that the determining factor in the process of wear nucleation under dynamic cyclic loading has a structural factor. Depending on the structure and properties of the material, as well as on the nature of the loads, the critical fatigue defect develops in the form of cracks, pores or microcraters. Comparative data of calculations and bench tests for droplet impingement erosion were presented. The contribution of the nucleation stage during the incubation period of erosive wear of the materials studied was evaluated. Due to the fact that rigorous instrumental methods for determining the duration of the nucleation stage are absent, the usage of the proposed analytical model is recommended for this purpose.
Structure, Texture and Mechanical Properties through the Section of the Hot-Extruded Tube of Titanium Alloy PT-1M
Authors: Vodolazskiy Fedor V. , Barannikova N.A. , Illarionov Anatoliy G.
Published: May 2020

The study considers the formation of the structure, texture, and hardness of hot extruded tube of titanium alloy PT-1M. It is shown that hot extrusion at 840 °C, which is higher than the α-phase recrystallization temperature, results to the development of dynamic and primary recrystallization processes and ensures the formation of homogeneous and fine-grained structure through-out the cross section with a two-component tangential texture (0001)TD<100>ED+(0001)TD<110>ED (TD – tangential direction, ED – extrusion direction) and hardness of 155 HV. It has been established that a higher cooling rate of the surface areas of the tube after extrusion results to a less active development of recrystallization processes, which lead to the formation of a finer granular structure near the outer surface. This weakens recrystallization component of (0001)TD<110>ED, compared to other areas of the tube.
Morphology of ZnO Films Fabricated by Electrochemical Oxidation of Metallic Zn
Authors: Kuz'mina A.S. , Kuzmina M.Yu. , Kuz'min M.P.
Published: May 2020

Anodic oxide films of zinc oxide in an aqueous solution of K Cl (0.1 M; 0.5 M and 1 M) were obtained by electrochemical oxidation of zinc metal. Zinc electrode was used as anode and platinum plate as cathode. The study discusses the influence of the concentrations of K Cl solution and the voltage applied to the electrochemical cell on the morphology of the obtained anode films, as well as their thermodynamic stability. The analysis of volt-ampere curves of linear potential sweep and chronoamperometric dependences showed that oxidation in 0.1 M K Cl solution at a voltage of 7.5 V allows to obtain continuous stable defect-free Zn O films on metal zinc.
Features of Zinc Extraction from Sulfide Forms
Authors: Sheshukov O.Yu. , Mikheenkov M.A. , Egiazaryan Denis K.
Published: May 2020

Zinc can be found in oxide and sulfide forms in technogenic formations. Zinc oxide extraction from technogenic formations is widely used in industry. Removing zinc sulfide from technogenic formations is difficult and is currently almost never used. In the present work, the physicochemical features of zinc extraction from sulfide are considered. Process thermodynamic features and possible ways to extract zinc sulfide are shown. Also, ways of valuable commercial products, obtaining from the roasting products, are considered.
Thermodynamic Modeling of Phase Equilibria in the FeO-MgO-Al2O3 System
Authors: Samoilova Olga V. , Makrovets Larisa A.
Published: May 2020

Thermodynamic modeling of coordinates of phase diagrams’ liquidus lines of the FeO–MgO, FeO–Al2O3, MgO–Al2O3 systems and coordinates of phase diagram’s liquidus surface of the FeO–MgO–Al2O3 system has been carried out. In the course of work, a thermodynamic model which describes activity of oxide melt had been selected for each of the systems; energy parameters of the model have been determined. Regions of thermodynamic stability of solid phases which are at equilibrium with the oxide melt have been determined. Results of the modeling have been compared with experimental data existing in the literature. Modeling technique has also allowed evaluating enthalpies and entropies of FeAl2O4 and MgAl2O4 compounds’ formation out of components of the oxide melt. The obtained results are of interest for steelmaking industry processes when determining the melt temperature of a slag containing oxides of iron, magnesium and aluminum.
Regulation of the Properties of Construction Composites Depending on the Material Composition
Authors: Gerasimova Ekaterina S. , Masharipova Kamila
Published: May 2020

This paper is devoted to research of directional regulation possibility of the properties of a composite based on the Portland cement by using limestone waste. It is shown that the introduction of limestone waste contributes to changing the nature of crystallization and structure formation of cement stone. With the introduction of limestone waste, in the amount of 15 % by weight of cement, it is possible to obtain the compositions of the class not less than B25-B35.
Cavitation Erosion-Corrosion Behavior of Fe-Cr Steel Induced by Ultrasonic Vibration
Authors: Alwan Hussam L. , Korobov Yury S. , Soboleva N.N. , Prokopyev D.A.
Published: May 2020

A resistance of cavitation erosion-corrosion of the AISI 420 martensitic stainless steel was evaluated in this study. The cavitation resistance of this stainless steel has been examined using an ultrasonic vibratory method by applying water-voltage combination effect. The curves of cumulative material loss and erosion rate were attained and discussed. In addition, surface topography and scanning electron microscope (SEM) micrographs have been utilized to characterize the eroded surface after the cavitation test. The results have been compared with previously obtained results for the AISI 1040 steel. The cavitation results showed that the AISI 420 steel has exhibited the better resistance to cavitation comparing with the AISI 1040 steel under the similar test conditions. The total cumulative material loss of the AISI 420 was approximately three times less than that of the AISI 1040. Surface topography and SEM micrographs showed that the severity of damage of the AISI 1040 was found to be a higher compared to that of the AISI 420 steel.
The Influence of Hardening Curve on the Shape and Size of the Neck of Specimen in Tensile Test
Authors: Erpalov Mikhail , Nukhov Danis Sh.
Published: May 2020

The article is devoted to the testing of samples for tensile, namely the formation of the neck. The objective of the study is to establish the qualitative level of influence of the nature of the hardening curve of the material on the shape and size of the neck. By using computer simulation, testing of samples of the two test materials, selected so as to provide the possibility of direct comparisons, forming the necks of the same diameter in the minimum section and the section near the neck, is worked over. It is found that the nature of the hardening curve determines the shape and size of the neck, including the radius of its curvature. This makes it possible to recover the hardening curve for large values of the strain. At the same time, it is established that the equation of the forming neck is invariant to the nature of the hardening curve of the material.
Analysis of the Engineering Process of Reforming Dead Catalysts for the Extraction of Platinum Group Metals
Authors: Vostrikova N. M. , Kravtsova E. D. , Vostrikova Y. V.
Published: May 2020

The analysis of the engineering process of reforming dead catalysts for the extraction of platinum group metals has been carried out. Fully-dead catalyst, having passed several cycles of regeneration and entitled to utilization, has the considerable carbonaceous deposits, both on external and internal surfaces. Their content averages 5.0% of the mass of the catalyst. The research objectively consisted in selection of the sweet roasting modes, promoting the fullest removal of the dense carbonaceous deposits from the surface of the dead platinum-rhenium catalysts. The kinetics research of carbonaceous removal deposits from the surface of the catalyst was carried out in a pipe-still heater; oxygen content, duration and temperature of sweet roasting being varied. The maximum temperature during the research reached 950°C, the maximum duration of isothermal holding didn't exceed 6 hours. The extent of carbonaceous deposits removal was calculated by changing sample weight. The kinetic curves were approximated by high-order polynomials, which made it possible to obtain a diagram, illustrating the degree of organic deposits removal, depending on temperature and firing time. It is shown that in the environment enriched to 30-35 vol. % oxygen, the engineering process of catalysts for regeneration is possible to be carried out at 650 °C, with holding for 2 hours at a specified temperature. The alternative of sweet roasting is the air blowing of dead catalysts at temperature of 800 °C within an hour. Both modes guarantee the complete removal of the dense carbonaceous deposits from the surface of the dead catalyst.
Prospects for the Use of Hollow Electrodes for Deep Desulfurization of Steel in the Ladle-Furnace Unit
Authors: Agapitov Evgeniy B. , Lemeshko Marina A. , Sokolova Margarita S.
Published: May 2020

The article discusses the possibilities of intensifying the process of desulfurization of molten steel in the process of after-furnace treatment of molten steel in the ladle-kiln unit. As one of the techniques, it was proposed to heat the melt with the help of hollow electrodes with argon feed during the operation of the electric arc plant. Comparative thermal balances of the installation in the basic and experimental versions and on the basis of the proposed mathematical model for calculating the mass-average temperature of the melt are given, and graphs of temperature changes during processing are plotted. To assess the efficiency of the desulfurization process, arrays of heats were processed in the basic and experimental mode and original three-parameter graphs were built, allowing to estimate the degree of desulfurization in both modes as a function of processing parameters.
Perspective Method for Regeneration of Spent Solutions from Printed Circuit Boards Etching
Authors: Makovskaya Olga Yu. , Shevchuk A.P. , Anikin Y.V.
Published: May 2020

The process of copper regeneration from spent hydrochloric acid etching solution of printed circuit boards is considered. A combined scheme is proposed, which includes the preliminary removal of excess chlorine ions from the solution, using a highly basic anion exchange resin and the subsequent electrochemical precipitation of copper. A solution contents, g/dm3: 237 Cu, 27 NH4Cl, 11.6 HCl was used. Electrical extraction was performed at a current density of 650 A/m2. The method makes it possible to prevent the emission of chlorine at the anode and ensures the obtaining copper as metal.
Regularities in Bimetal Joint Formation at Explosion Welding with Simultaneous Stamping
Authors: Kuz'min Vladimir I. , Lysak Vladimir I. , Kuz’min Evgeniy V.
Published: May 2020

This paper reports the investigation of the effect of a plate dynamic loading scheme upon bimetal joint formation at explosion welding with simultaneous stamping. The investigation results of the effect of technological parameters and matrix material upon a radial deformation and quality of explosive pressed аrmco iron+steel 3 bimetal are shown. It is determined experimentally, that additional punching in modes common for explosion welding, without their intensification, allow achieving considerable deformations and manufacturing qualitative bimetal blanks with a high factor of a part form.
Staged Local Dissolution of Stainless Steel in Chloride Solutions
Authors: Vinogradova Svetlana S. , Pleshkova Ye.V.
Published: May 2020

The paper defines galvanostatic polarization parameters (current density and test duration), to simulate self-dissolution conditions; the results are confirmed by potentiostatic tests. It is shown that under the conditions of self-dissolution simulation, increasing the solution concentration reduces the nucleation rate, while prolonging the pitting development time. Spectral analysis of chronopotentiograms reveals low-frequency potential fluctuations that characterize the nucleation and passivation of pits at the onset of pitting corrosion. The paper describes the basic regularities, observed in the alteration of surface electrochemistry by impedance spectroscopy; such alteration corresponds to the transition from the passive area to the pitting area. The researchers propose optimal electric equivalent circuits to reflect the surface conditions in early nucleation of pits. The paper also proposes an additional pitting resistance criterion, that is, cumulative electric-charge density.
Study of the Processes of High Temperature Material Heating for Plasma Recycling
Authors: Matushkin A.V. , Anakhov S.V. , Pyckin Yu.A.
Published: May 2020

The processes of high temperature material heating for plasma recycling are investigated. The gas-dynamic parameters of the air-plasma flow in the plasma torch mixing chamber for ecology technologies are determined by methods of mathematical modeling. The characteristic temperatures, velocities and heating times of the utilized gas in different areas of the mixing chamber are determined. The directions of further research and development necessary to create a technology of plasma recycling with maximum efficiency are outlined. The issues of plasma recycling introduction at certain stages of high-temperature technologies are also considered.
Obtaining and Research of Additive Products from Electro-Erosive Cobalt-Chrome Powders
Authors: Ageev Evgeniy V. , Loktionova O.G. , Altukhov A.Y.
Published: May 2020

The main requirement for powders for additive machines is the spherical shape of the particles. Such particles most compactly fit into a certain volume and provide the “fluidity” of the powder composition in the material supply systems with minimal resistance. Based on the peculiarities of the methods of obtaining spherical powders in order to obtain spherical granules of a regulated grain size, the technology of electroerosive dispersion, which is distinguished by relatively low energy costs and ecological cleanliness of the process, is proposed. The main advantage of the proposed technology is the use of waste as raw materials, which is much cheaper than the pure components used in traditional technologies. In addition, this technology is powder, which allows to obtain powder-alloys. The widespread use of the method of EED for the processing of metal waste into powders for the purpose of their reuse and application in additive technologies is hampered by the lack of complete information in the scientific and technical literature on the influence of the original composition, modes and media on the properties of powders and technologies of practical application. Therefore, the development of technologies for the reuse of EED powders and the evaluation of the effectiveness of their use requires the conduct of comprehensive theoretical and experimental studies. The purpose of this work was to obtain and study additive products from electroerosive cobalt-chromium powders of a specific particle size distribution and to study their microstructure. The granulometry of the obtained powders was determined on a laser analyzer of particle sizes “Analysette 22 NanoTec”. The microstructure of additive samples from cobalt-chromium powders (by transverse polishing) was investigated by optical microscopy on an inverted optical microscope OLYMPUS GX51. On the basis of completed studies, aimed at obtaining and studying additive products from electroerosive cobalt-chrome powders of a specific particle size distribution, and studying their microstructure, it was found that additive samples, obtained from a cobalt-chrome powder with an average particle size of 35,68 microns, have practically no pores.
Heatproof Relaxation of Welding Stresses Openwork Designs of Large Size Ultrasonic Field
Authors: Toan Nguyen Khanh , Kiselev E.S.
Published: May 2020

Designed experimental setup, and a prototype of the original devices for athermic relaxation of thermal residual stresses in openwork welded constructions of large dimensions for the rational use of energy high-frequency acoustic (ultrasonic) fields, conducted laboratory studies and pilot tests in real conditions of production. Ultrasonic relaxation when welding thin-walled constructions standard openwork rolled steel profiles 10 large dimensions (up to 3 x 10 m). It has been established that with a decrease in the time of ultrasonic relaxation, the efficiency of its use decreases somewhat. Therefore, in an industrial environment, it is advisable to use the duration of ultrasonic treatment in the range of 0.02-0.04 min per mm of weld length.