bluuebunny/crossref_metadata_2025_split huggingface dataset:
POSSIBILIDADES PARA ENSINAR CONCEITOS DE FORÇA DE ARRASTO EM MEIO FLUÍDO LÍQUIDO
Authors: Fontes Adriana da Silva , Dos Santos Oscar Rodrigues , Batista Michel Corci 
Published: September 2021

Neste trabalho apresentamos algumas possibilidades para se trabalhar força de arrasto em meios viscosos, tendo em vista Ã dificuldade de encontrar materiais sobre esse conteúdo na disciplina de Física 1, tanto em nível médio como na graduação. A Sequência didática desenvolvida foi aplicada na disciplina de Física 1, em uma turma contendo 13 alunos do curso Superior de Licenciatura em Química, de uma Universidade Pública no interior do Paraná. O assunto abordado, faz parte da ementa da disciplina. Para levantar os conhecimentos prévios dos alunos sobre o assunto foi aplicado um Quiz na plataforma do Kahoot. Após, foram realizadas aulas expositivas-dialogadas e na sequência, atividades práticas virtuais através de simuladores (disponibilizados por Algodoo, Phet Colorado e NOA) e uma atividade prática experimental no laboratório de Física utilizando a vídeo análise por meio do software Tracker, Open Camera e o editor de planilhas do Excel, os quais possibilitaram a investigação do comportamento de uma esfera em queda em três meios viscosos, quadro a quadro. Os resultados indicaram que a SD contemplando o formalismo matemático e atividades experimentais aliada Ã s Tecnologias Digitais de Informação e Comunicação (TDIC’s) possibilitou trabalhar os conceitos físicos envolvidos; ensinou a utilizar a tecnologia a favor do ensino e mostrou aos futuros professores, formas alternativas e complementares para se trabalhar o conteúdo, podendo esta ser utilizada por outros professores, pois os materiais utilizados nos experimentos reais, são de baixo custo e de fácil reprodução e as atividades realizadas, por meio das TDIC, são de amplo acesso e permitem realizar práticas com rapidez e qualidade.
Diferentes distúrbios antrópicos na paisagem podem influenciar padrões florísticos e estruturais da Mata Atlântica?
Authors: Paschoal Elisa Morais , Vieira Arthur Duarte , Otoni Thiago José Ornelas , Gripp Aglaia Maciel , Freire Jessica Pereira , Alves Pablo Lopes , Gonzaga Anne Priscila Dias , Machado Evandro L. M. 
Published: September 2021

Este estudo teve por objetivo descrever e comparar as diversidades alfa e beta e estrutura do componente arbóreo em remanescente de Floresta Estacional Semidecidual. A vegetação arbórea foi amostrada em duas bordas em contato com pastagem (BP), cafeicultura (BC), e no interior do fragmento (INT). Foram amostrados no total 2.840 indivíduos, identificados em 56 famílias, 144 gêneros e 271 espécies (94 na BC, 128 BP e 178 INT). Os trechos de borda foram caracterizados por maior densidade e menor área basal que o interior, indicando a influência de distúrbios. As variações na composição florística estrutural das comunidades arbóreas sofreram influência das variações ambientais regionais e locais, além do histórico de uso da área, conforme as Teorias de Nicho e do Distúrbio Intermediário. Different Anthropic Disturbances in the Landscape can influence Floristic and Structural Patterns of the Atlantic Forest? This study aimed to describe and compare the floristic and structural component of the tree component, as well as the alpha and beta diversity, as well as the floristic similarity of a remnant of Semideciduous Forest. The tree vegetation was sampled at two edges in contact with pasture (BP) and coffee growing (BC), and inside the fragment (INT). 2.840 individuals were sampled, identified in 56 families, 144 genera and 271 species (94 BC, 128 BP and 178 INT). The border stretches were characterized by higher density and smaller basal area than the interior, indicating the occurrence of disturbances. The variations in the structural floristic composition of the tree communities wereinfluenced by regional and local environmental variations, as well as the historical use of the area, according to Niche and Intermediate Disturbance Theories.Keywords:Phytosociology, Intermediate Disturbance Theory, Serra do Espinhaço Biosphere Reserve.
The Effect of Adding High-Density Polyethylene Polymer on the Engineering Characteristics for Sandy Soil
Authors: Jasim Noor Al-huda , Shafiqu Qassun S , Ibrahim Mohammed A 
Published: September 2021

The loose sand is subject to large settlement when it is exposed to high stresses. This settlement is due to the nature of the high drainage of sand, which displays foundations and constructions to a large danger. The densification of loose sandy soils is required to provide sufficient bearing capacity for the structures. Thus soil stabilization is used to avoid failure in the facilities. Traditional methods of stabilized sandy soil such as fly ash, bituminous, and cement often require an extended curing period. The use of polymers to stabilize sandy soils is more extensive nowadays because it does not require a long curing time in addition to being chemically stable. In this study, the effect of adding different percentages of high-density polyethylene HDPE to the sandy soils' engineering characteristics such as the angle of internal frictions Ø0, shear strength τ, California Bearing Ratio CBR, and permeability k was studied. The results of laboratory tests showed that using of HDPE at percentages (0.1, 0.3, 0.6, 1, and 3%) led to a decrease in soil permeability by 18% and an increase in both the angle of internal friction, the CBR value, and shear strength about 27.2%, 180.9%, and 38.6 % respectively by adding 1%. HDPE.
Perceived stigma among caregivers of mentally ill patient: A descriptive cross-sectional study
Authors: Khanal Pratibha 
Published: September 2021

Background: Stigmatising experience related to mental illness is not only confined to the patient but also experienced by their caregivers such as family members and friends. Caregivers feel down and helpless about their affiliation with stigma related to mental illness. Various research studies show that stigma related to mental illness have negative influence on caregivers which leads to concealing the status of mentally ill relatives.
Objective: This study aimed to assess the level of perceived stigma among the caregivers of mentally ill patients.
Methods: A descriptive cross-sectional study was conducted at Psychiatric outpatient and inpatient department of Psychiatry, Kathmandu Medical College from 30th January to August 30th 2020. Two hundred and sixteen respondents were chosen conveniently. Face to face interview was conducted using standard tool ‘Devaluation Consumers Families Scale’ to assess the perceived stigma among caregivers of mentally ill patients.
Results: Perceived stigma among the caregivers of mentally ill patients was found to be medium (mean score 15.8±2.8). The caregivers perceived the community looking down on the families with mentally ill relatives (community rejection). The mean score was low (2.1±0.8) on “uncaring parents” which indicates that the respondents did not agree that parents of mentally ill patients were less responsible and caring than others.
Conclusion: Caregivers of mentally ill patient perceive stigma in various forms which affects the usages of health facilities, care and support towards mentally ill relatives.
Objective: This study aimed to assess the level of perceived stigma among the caregivers of mentally ill patients.
Methods: A descriptive cross-sectional study was conducted at Psychiatric outpatient and inpatient department of Psychiatry, Kathmandu Medical College from 30th January to August 30th 2020. Two hundred and sixteen respondents were chosen conveniently. Face to face interview was conducted using standard tool ‘Devaluation Consumers Families Scale’ to assess the perceived stigma among caregivers of mentally ill patients.
Results: Perceived stigma among the caregivers of mentally ill patients was found to be medium (mean score 15.8±2.8). The caregivers perceived the community looking down on the families with mentally ill relatives (community rejection). The mean score was low (2.1±0.8) on “uncaring parents” which indicates that the respondents did not agree that parents of mentally ill patients were less responsible and caring than others.
Conclusion: Caregivers of mentally ill patient perceive stigma in various forms which affects the usages of health facilities, care and support towards mentally ill relatives.
The Effect of Water Absorption in Ceramic Coatings on High Frequency ac Resistance
Authors: Bobzin K. , Wietheger W. , Burbaum E. 
Published: September 2021

Abstract
Thermally sprayed ceramic coatings can be used for wear protection as well as thermal and electrical insulation. When exposed to environments with high humidity, the water absorption of the ceramic coating has a tremendous impact on the electrical insulation. In thermally sprayed ceramic coatings, water can easily be absorbed by the porous microstructure of the coating. A general result of the water absorption is the reduction of the dc resistivity. However, in the high frequency regime of ac loads, contrary results were observed for sealed Al2O3 coatings on steel substrates. Specimens exposed to high air humidity have shown an increased ac resistance compared to dry specimens if frequencies above 1 MHz are considered. To analyse this phenomenon, a novel measurement technique was developed to investigate the influence of the water absorption of detached ceramic coatings on the ac resistivity at high frequencies. Moreover, the water absorption of the ceramic is measured gravimetrically. To ensure the results are also applicable to ceramic coatings on substrates, the morphology of the coating was analysed using electron microscopy and compared to reference specimens deposited on steel substrates from [1].
Thermal Spraying of FeMnCrSi Alloys: An Overview
Authors: Vaz Rodolpho F. , Pukasiewicz Anderson G.M. , Siqueira Irene B.A.F. , Sucharski Gustavo B. , Chicoski André , Tristante Romildo 
Published: September 2021

Abstract
FeMnCrSi alloys have been developed and studied over the past several years with an emphasis on their use as coatings on CA6NM stainless steel hydroturbine components. Much of the work conducted has focused on the optimization of cavitation resistance through chemical composition changes, the use of different thermal spraying (ASP, HVOF, HVAF) and welding (PTA) processes, and post-treatments such as shot-peening, cold working, and PTA remelting. The aim of this current work is to present a compilation of published articles that report on the research that has been done. Among the trends observed is that coating density and cavitation resistance improve with increasing particle velocity, particularly for HVOF-kerosene spraying. In regard to post-treatments, cold working was found to most effective, reducing cavitation mass loss (in PTA FeMnCrSi coatings) by a factor of nearly two.
Fabrication of Porous Aluminum Coating by Cored Wire Arc Spray for Anchoring Antifouling Hydrogel Layer
Authors: Wen Jianxin , Song Ziheng , Chen Xiuyong , Li Hua 
Published: September 2021

Abstract
Biofouling has been persisting as a worldwide problem due to the difficulties in finding efficient environment-friendly antifouling coatings for long-term applications. Developing novel coatings with desired antifouling properties has been one of the research goals for surface coating community. Recently hydrogel coating was proposed to serve as antifouling layer, for it offers the advantages of the ease of incorporating green biocides, and resisting attachment of microorganisms by its soft surface. Yet poor adhesion of the hydrogel on steel surfaces is a big concern. In this study, porous matrix aluminum coatings were fabricated by cored wire arc spray, and the sizes of the pores in the aluminum (Al) coatings were controlled by altering the size of the cored powder of sodium chloride. Silicone hydrogel was further deposited on the porous coating. The hydrogel penetrated into the open pores of the porous Al coatings, and the porous Al structure significantly enhanced the adhesion of the hydrogel. In addition, hydrogel coating exhibited very encouraging antifouling properties.
Development of Suspension-Based Plasma and HVOF Spray TiO2 Coatings
Authors: Mittal Garima , Sabard Alexandre , Fanicchia Francesco , Bhamji Imran , Paul Shiladitya 
Published: September 2021

Abstract
Thermal spray is a versatile process that produces high-quality coatings possessing diverse properties such as superhydrophobicity, wear resistance, corrosion resistance, dielectric properties etc. Conventionally, powder feedstock is used in thermal spray, and this process is commercialised in numerous industrial processes. However, liquid feedstock based thermal spray is still in its development phases, due to limited information available on process parameters. Various parameters such as plasma/fuel gas, plasma current, feedrate, feeding angle, type of feedstock (suspension or solution precursor), feedstock concentration, feedstock viscosity, solvent, etc. significantly influence the thermal and kinetic energy exchange between plasma/flame and feedstock material. Suspension plasma spray (SPS) and suspension high velocity oxy-fuel spray (SHVOF), once optimised, can give rise to coatings with multiscale features. An in-depth understanding of the complex interaction between feedstock solution/suspension chemical-physical properties and plasma/flame jet characteristics is essential to understand its specific impact on coating properties and their application. This paper presents comparisons between two different TiO2 coatings, deposited by SPS and S-HVOF, and obtained by varying some of the fundamental spray deposition parameters. The surface morphology and cross-sections of the as-deposited coatings were compared through SEM/EDX. Further, surface wetting properties were analysed through measuring the static and dynamic contact angles.
Investigation of Mechanical Properties of Twin Wire Arc Repair of Cast Iron Components
Authors: DePalma K. , Walluk M. , Martin L.P. , Sisak K. 
Published: September 2021

Abstract
Twin wire arc is a commonly used thermal spray technology for application of steel coatings to cast iron components. Hardness and adhesion strength are critical properties of such coatings, and significant research is available reporting these properties. However, residual stresses and the anisotropic structure of the coatings leads to significantly different behavior in bending applications than in the purely tensile loading of the standard adhesion test. In addition, microstructural features that are controlled by certain process parameters during deposition of the coating can have a significant effect on these properties. This work seeks to relate the hardness and pull-off adhesion strength to the coating microstructure, and to assess the related bending strength and failure mode. Comparisons between bend tests and pull-off adhesion tests show significant differences to consider when evaluating twin wire arc coatings.
The Influence of the Substrate Topography on the Plasma Jet Flow and Particle Deposition as a Determining Factor of Thermal Barrier Coatings Build-Up Mechanisms in Plasma Spraying
Authors: Kiełczawa Tomasz , Sokołowski Paweł , Małachowska Aleksandra 
Published: September 2021

Abstract
The aim of this work is to better understand the build-up of thermal barrier coatings (TBC) on microtextured substrates, particularly the influence of geometry on the behavior of plasma jets in substrate boundary layers. Coatings produced by suspension plasma spraying served as an experimental reference for numerical analysis, which involved advanced turbulent flow and volumetric heat source modeling along with the use of commercial fluid flow software. Geometric and numerical models were used to simulate the generation of plasma inside the torch and the resulting plasma flow with its highly nonlinear thermophysical characteristics. This work opens the possibility of predicting feedstock particle movement and deposition, which is essential in understanding coating build-up mechanisms in general and the flow of fine particles on substrate surfaces in particular.
The Cavitation Resistance of WC-10Co4Cr and WC-20CrC-7Ni HVAF Coatings
Authors: Korobov S. , Lezhnin N.V. , Makarov A.V. , Alwan H.L. , Shumyakov V.I. , Soboleva N.N. , Antonov M. , Deviatiarov M.S. 
Published: September 2021

Abstract
Two kinds of cermet powders, WC-10Co4Cr and WC-20CrC-7Ni, were deposited on 1040 steel via high velocity air fuel (HVAF) spraying to evaluate resistance in cavitation erosion conditions with additional electrochemical effects. Coating microstructure, phase composition, and microhardness were examined along with the topography of eroded surface layers. The cavitation resistance of the WC-20CrC-7Ni coating was found to be approximately 1.3 times greater than that of the other coating, which can be attributed to its finer grain structure, lower pore density, and the presence of high Cr and Ni content in the feedstock powder which serves to strengthen the matrix.
Microstructure and Ablation Behavior of Very Low-Pressure Plasma Sprayed ZrB2-Based Coatings
Authors: Wang Di , Luo Xiao-Tao , Li Chang-Jiu 
Published: September 2021

Abstract
The effect of deposition pressure on the microstructure and ablation behavior of ZrB2 coatings deposited by very low pressure plasma spraying is investigated. The results show that under a chamber pressure less than 50 kPa, as the spray chamber pressure decreases, the porosity of the coating deposited at the same distance decreases, and the coating prepared under 100 Pa presents the lowest porosity of 1.79 %. Furthermore, among the ZrB2 coatings deposited at 100 Pa, 5 kPa, 10 kPa and 50 kPa, the dense coating deposited at 100 Pa showed the lowest ablation rate of 0.33 μm/s, 0.75±0.08 mg/s.
Thermally Sprayed Coating-Based Heating Systems for Boundary Layer Transition Detection — An Experimental Approach
Authors: Machulla M. , Dehaghani S. Taghian , Claußnitzer P. , Scheitz S. , McDonald A. , Leyens C. 
Published: September 2021

Abstract
Boundary layers on surfaces will change from laminar to turbulent flow after a critical length. Due to the differing heat transfer coefficients of laminar and turbulent flow, the point of transition can be detected by heating the surface and measuring surface temperature by thermographic imaging. Locating the transition point is crucial for the aerodynamic optimization of components. In this study, fiber reinforced polymer composites (FRPCs) were chosen as the test substrate. Experiments were conducted using the flame spray process and NiCrAlY coatings. Multilayered coatings consisting of an aluminum bond coat, a layer of alumina as electrical insulation, and a heating layer of titania were fabricated by atmospheric plasma spraying. Free-flight tests were conducted with a functionalized winglet in order to assess the ability of thermally-sprayed heating elements to detect the location of transition of the flow regime. The results showed that the thermally-sprayed elements heat surfaces uniformly, with sufficient radiation losses for thermographic imaging. It was also shown that the change in temperature at the point of transition was readily observable using thermography.
DIREITOS HUMANOS NO CURSO DE LICENCIATURA EM QUÍMICA DO IFPI CAMPUS TERESINA CENTRAL
Authors: Araujo Raiane de Oliveira , Dos Santos Vanessa Nunes 
Published: September 2021

A formação de educadores em direitos humanos pode orientá-los a ideia de transversalidade e interdisciplinaridade. Essas dimensões pedagógicas possibilitam, orientar os currículos escolares a fomentar uma cultura de direitos , uma vez que permitem a implantação dos conceitos dos direitos humanos em todas as disciplinas dos cursos de graduação e em toda a forma organizacional dos programas de formação continuada. A educação em direitos humanos emergiu como um potencial significativo no contexto de busca por um novo estado de direito, e tem ganhado maior visibilidade e importância na perspectiva de formação docente dentro das academias. As instituições de ensino possuem uma grande responsabilidade na criação de espaços para a cultura de Direito Humanos, estes devem estar nos currículos, nas avaliações, na capacitação de professores e outros. Deste modo, foi desenvolvida esta pesquisa com o objetivo de compreender a proposta de formação docente para atuação na perspectiva da educação para a diversidade e inclusão do curso de licenciatura em química ofertada pelo Instituto. Em função da natureza do objeto de estudo, foi abordada a questão dos direitos humanos, trazendo uma análise do currículo do curso de licenciatura em química do IFPI Campus Teresina Central, refletindo como ele prepara (ou deveria preparar) um professor com formação humanista. A questão norteadora da pesquisa é: qual a fundamentação que um licenciando recebe para lidar com questões como direitos humanos, políticas de inclusão, sociedade e meio ambiente? Conclui-se desse modo, que o currículo é uma construção permanente o Projeto político pedagógico do Curso de Licenciatura em química desde sua implantação vem sendo adequado conforme as políticas e demandas na formação de professores. Portanto, conclui-se que tal processo formativo a qual está centrado a questão dos direitos humanos na formação docente é uma das etapas fundamentais para que o professor, no futuro, se veja como um profissional atuante como Agente Sociocultural e Político, vindo a dar voz aos diversos grupos sociais e questionando as desigualdades sociais existentes, lutando pelo enfrentamento da equidade desses grupos na sociedade, buscando por uma sala de aula pautada no diálogo entre os diversos saberes e vivências que traga o estudante como sujeito ativo de uma reivindicação necessária e de uma mudança possível
Soil property variability in a humid natural Mediterranean environment: La Rioja, Spain .
Authors: Jiménez-Ballesta Raimundo , S. Andrades Marisol , Marín Álvaro , Íñigo Victoria , Alonso-Martirena Juan I. 
Published: September 2021

Estimating the spatial variability of soil properties is significant for evaluating environmental impacts. For example, many soil properties are directly used in the modelling of environmental processes such as global climate change. These aspects have not previously been studied at this level in La Rioja (a region of Spain with a humid Mediterranean environment). The intention of this study was to provide quantitative information on soil assessment and mapping methods for natural soils in a humid Mediterranean environment. The properties considered included: pH and organic matter, calcium carbonate and clay contents. For testing, samples were selected from several different soil types which, in theory, were only affected by pedogenetic processes and had developed on different parent materials. More than half of the samples did not contain any CaCO<sub>3</sub>, while the rest of the samples presented a variety of CaCO<sub>3</sub>, forms, with high percentages being present in certain cases (up to 65% on the surface). It was possible to establish two different areas: one predominantly acidic and the other principally basic. The predominately basic samples were due to the high percentage of carbonate in the parent materials. The clay content on the surface was similar to that in the subsurface layers. Finally, the organic matter contents in the uppermost layers presented average values of 3.9%,with a range of from 0.3 to 17.5%. The major variations in soils were determined by soil type (therefore by soil forming processes), parent material composition, and vegetation type. This study reveals that these methods are useful to determine the spatial distribution of some soil properties in undisturbed soils. The contour maps of soil property variability could be used to improve future sampling designs and management decisions.