bluuebunny/crossref_metadata_2025 huggingface dataset:
Accidental Canon
Authors: Berman Patricia G.
Published: December 2024

This case study in decanonization examines the making of the exhibition Northern Light: Realism and Symbolism in Scandinavian Painting, 1880–1910 (US and Sweden, 1982–1983). The exhibition became established in the Anglophone world, and internationally, as a framework for understanding Nordic art. It has become a canon that has shaped – and continues to effect – academic and museum practice. The article examines the institutional apparatus and the contingency of circumstances that shaped the contours of the exhibition and thus the canonical model it generated. Among them are the national exigencies in the US (and the five Nordic nations), the scholarly vision of curator Kirk Varnedoe, the exceptional rapidity with which the exhibition was realized, the relatively few Anglophone scholarly sources available in English, and the various pressures placed on the project. The article questions the process of canonization through which an ephemeral exhibition, created for a manifest national purpose in the U.S., generated an enduring art-historical model, even a stereotype. Through a close study of the planning process, the contingent nature of the canon is examined.
"Ich, die Dichterin von Arabien"
Authors: Ingold Julia
Published: December 2024

In early twentieth-century Germany, Orientalist imagery and stereotypes provided an important and successful repertoire for the entertainment industries. Cruel colonial practices such as ethnological exhibitions appeared side by side with dreamy art and narratives in the style of the Arabian Nights. Meanwhile, antisemitism was on the rise, particularly following Germany’s defeat in World War I. In the same decades, a certain taste for Jewish mysticism, namely the Kabbalah, appeared, along with the rise of esotericism and vitalism. This article considers Else Lasker-Schüler, a German-Jewish multimedia artist whose works comprise poems and prose as well as graphically elaborate letters, arabesque drawings, and performances in Orientalist settings within this historical context. Inspired by the surrounding Orientalist entertainment industry, Lasker-Schüler’s imageries and story worlds prove exceptional among German Orientalist initiatives because of the way she claims them for herself. Using the logic of mystification, alienation, and commercialization, Lasker-Schüler creates a certain image of herself as artist that allows her to become the other not only in terms of content but also through formal expressions.
Presencia de insectos en caraota Phaseolus vulgaris L., sector Mundo Nuevo, parroquia Juan Ángel Bravo, municipio Ezequiel Zamora, Cojedes Venezuela
Authors: Flores Yadira , Alcalá Algerbert , Escobar Ángela , Mújica Yinny , García Miguel
Published: December 2024

Las leguminosas de grano, como la caraota Phaseolus vulgaris L., son fundamentales en la alimentación humana debido a su alto contenido de proteínas, carbohidratos complejos y bajo contenido de grasa, siendo una opción económica y nutricionalmente adecuada frente a productos de origen animal. En Venezuela, la caraota es un cultivo estratégico por su aporte proteico y su capacidad para adaptarse a diversos suelos y climas adversos, además de mejorar la fertilidad del suelo a través de la fijación de nitrógeno. Se realizó un estudio en el sector Mundo Nuevo, municipio Ezequiel Zamora, Cojedes, cuyo objetivo fue identificar diversas plagas que afectan el cultivo de caraota. Los resultados indican la presencia de coquitos perforadores Andrector arcuatus (Olivier) y Andrector ruficornis (Olivier), chicharritas Empoasca kraemeri (Ross y Moore) y Agrosoma sp. y trips (Thrips sp.). Estos insectos causan daños significativos, como perforaciones en hojas, chupado de savia y transmisión de enfermedades virales, afectando negativamente los rendimientos del cultivo. Además, se identificaron insectos benéficos como Podisus sp. (Hemiptera: Pentatomidae), Cycloneda sanguinea (L.) (Coleoptera: Coccinellidae), Diptera- Tachinidae, y Zelus sp. (Hemiptera: Reduviidae). Estos biorreguladores cumplen una importante función en el ecosistema agrícola al controlar poblaciones de insectos plaga. Por lo tanto, es crucial implementar prácticas agronómicas que favorezcan la conservación de estos insectos benéficos, como el uso de trampas de colores y repelentes naturales, en lugar de productos químicos. La caraota no solo es una fuente nutricional esencial sino también un cultivo vital para la seguridad alimentaria en Venezuela. Sin embargo, la presencia de diversas plagas representa un desafío considerable para los agricultores. La identificación y manejo adecuado de estas plagas, junto con la conservación de insectos benéficos, son fundamentales para asegurar la sostenibilidad y el éxito del cultivo de caraota en el sector Mundo Nuevo y otras regiones similares.
Microencapsulación en la industria alimentaria: avances y tendencias actuales
Authors: Zambrano Vélez María Isabel , Vera Zambrano Allison Milenka , Vera Arteaga Teddy Alfredo
Published: December 2024

La microencapsulación en la industria alimentaria ha surgido como una técnica prometedora para mejorar la calidad, seguridad y funcionalidad de los productos alimenticios, respondiendo a la creciente demanda de alimentos funcionales y nutricionalmente mejorados. El problema radica en la necesidad de proteger ingredientes activos sensibles a factores ambientales durante el procesamiento y almacenamiento de alimentos. La presente investigación de revisión tiene como objetivo analizar el impacto de la microencapsulación en la estabilidad de los ingredientes y su relevancia en la industria alimentaria. La investigación se basó en una revisión bibliográfica exhaustiva de fuentes especializadas en microencapsulación de alimentos a nivel nacional e internacional. Se utilizaron criterios de búsqueda específicos en bases de datos científicos para seleccionar documentos relevantes. La microencapsulación protege ingredientes sensibles a factores externos como luz, oxígeno y humedad permitiendo la creación de alimentos funcionales con propiedades mejoradas para la salud y contribuye a la estabilidad y biodisponibilidad de los ingredientes activos en los alimentos. La microencapsulación en la industria alimentaria es una técnica clave para mejorar la calidad y funcionalidad de los productos, ofreciendo beneficios como protección de ingredientes sensibles y creación de alimentos funcionales. Su aplicación puede ser fundamental para satisfacer las demandas de los consumidores modernos y promover la innovación en la industria alimentaria.
Caracterización de resultados de la evaluación fibroscópica de la deglución en los niveles IDDSI 0,3 y 7 según la Escala de Penetración Aspiración
Authors: Nanjarí R. Amalia , Campos María del Carmen
Published: December 2024

INTRODUCCION: Establecer la severidad de la disfagia a través de la Escala de Penetración Aspiración según niveles IDDSI 0, 3 y 7 en sujetos adultos derivados a evaluación fibroscópica de la deglución por sospecha de disfagia en el Hospital San Camilo de San Felipe.  Métodos: Estudio de enfoque cualitativo, alcance correlacional y diseño no transversal y experimental transversal y muestreo por conveniencia. incluyeron 30 personas (entre 20 y 92 años) derivadas a evaluación fibroscópica de la deglución, con Glasgow 15 y con S5Q menor o igual 4/5. Se consignaron los resultados obtenidos mediante la Escala de Penetración-Aspiración de los niveles 0,3 y 7 de la Iniciativa Internacional de Estandarización de la Dieta para la Disfagia. Resultados: El promedio de edad correspondió a 60 años, el 26,7% presentaba patologías neurológicas y el 16,7% enfermedades respiratorias. En el 76,7% de los participantes no se objetivó entrada de material a vía aérea (PAS=1) en todas las consistencias y medidas evaluadas, el 13,3% evidenció alteraciones de la seguridad con IDSSI 0, el 6,6% en IDSSI 3 y el 10% con IDSSI 7. Conclusiones: Este estudio proporciona una caracterización del examen FEES en una muestra local, así mismo se observa la necesidad de contar a nivel nacional con un protocolo FEES estándar que permita homologar criterios.
He Whanaungatanga Tīmatanga: The Treaty of Waitangi, Artificial Intelligence and our Schools
Authors: Shaw Brendon
Published: December 2024

This opinion piece explores the intersection of artificial intelligence (AI), The Treaty of Waitangi, and New Zealand schools from the perspective of a Māori educator. The author reflects on personal experiences with AI and discusses the rewards and potential risks Māori face when dealing with artificial intelligence. The piece then looks at how the Treaty’s principles of partnership, participation, and protection can coexist with AI and offers suggestions on how AI can be integrated into Māoritanga in a respectful and collaborative way.
How do schools give effect to Te Tiriti o Waitangi in the current political climate?
Authors: MacKintosh Rochelle
Published: December 2024

The Education and Training Act 2020 requires schools to give effect to Te Tiriti o Waitangi. However, the newly elected National coalition-led government has sent contradictory messages about Te Tiriti o Waitangi, which may be confusing educators. For example, recent actions by the government, such as repealing laws, are harming their relationship with iwi Māori and have undone decades of Māori progress. While the government may be sending educators contradictory messages, educators play a crucial role in teaching students about Te Tiriti o Waitangi which can promote a unified understanding. Suppose all educators and students have a sound knowledge of Te Tiriti, they can better comprehend the historical injustices that Māori have endured and the intergenerational effects that continue to impact Māori today. With contradictory messages from the government and different interpretations about Te Tiriti o Waitangi, what should educators be teaching students about Te Tiriti o Waitangi? This article aims to contribute to a collective understanding of Te Tiriti o Waitangi in education by discussing the articles of Te Tiriti o Waitangi and the Treaty of Waitangi. I also offer suggestions for how schools could give effect to Te Tiriti o Waitangi despite the confusing messages being received by the government.
Envejecimiento y lenguaje. Corpus de muestras de habla de personas con deterioro cognitivo leve en entrevistas estructuradas. Presentación del libro
Authors: Mendizabal de la Cruz Nieves , González Martín Enrique , Jimeno Bulnes Natalia , Sánchez Gil Carolina
Published: December 2024

La mejor manera de adentrarse en el conocimiento del lenguaje es a través del análisis de las muestras de habla que manifiestan los seres humanos en sus interacciones orales. En Envejecimiento y lenguaje. Corpus de muestras de habla de personas con deterioro cognitivo leve en entrevistas estructuradas, los autores reúnen en un corpus de entrevistas orales las muestras de habla grabadas, y posteriormente transcritas, en centros sociosanitarios de población mayor de 65 años, pocos meses antes de la pandemia por COVID-19. A partir del análisis de su discurso, desde la lingüística de corpus y la pragmática conversacional, se ofrece a los profesionales de la logopedia, a los investigadores y a los familiares de personas con alteraciones del lenguaje por deterioros neurocognitivos, una fuente empírica de muestras de habla obtenidas en entrevistas semiestructuradas entre un logopeda y una persona mayor con deterior cognitivo leve o moderado. A través del análisis de las características lingüísticas y de las manifestaciones psicopatológicas de las personas entrevistadas, los logopedas y profesionales interesados tendrán a su alcance un conjunto de muestras de habla con las que contribuir a mejorar la atención y la calidad de vida de los mayores, así como una ayuda para la creación de programas específicos de intervención en la comunicación de nuestros mayores.
Torsades de Pointes induced by propofol in a patient with Wolff Parkinson White Syndrome: Case report
Authors: Souza Anna Luiza , Oliveira Larissa Xavier Alves de , Alessi Silvio Roberto Borges , Prudente Mauricio Lopes , Frota Elano Sousa da , Guimarães Ellen Gonçalves , Silva Ricardo Curado de Oliveira e , Gardenghi Giulliano
Published: December 2024

We describe a clinical case of a 57-year-old female patient with Wolf Parkinson White Syndrome, who, during anesthetic induction with propofol for ablation of the accessory pathway, presented polymorphic ventricular arrhythmia, specifically Torsades de Pointes.
Planeación y régimen político en la Ciudad de México. Los límites a las innovaciones constitucionales
Authors: Canto Chac Saturnino Manuel
Published: December 2024

Este trabajo analiza las principales causas de la disociación entre la perspectiva de planeación establecida en la Constitución de la Ciudad de México y los proyectos de instrumentos de planeación en la CDMX, mismos que han sido retirados por el actual Jefe de Gobierno, estas causas son: 1) la falta de capacidad para operar las transformaciones necesarias en el régimen político de la ciudad; 2) la ausencia de una estrategia para cambiar el modelo de desarrollo socioeconómico y de gestión pública neoliberales; 3) la falta de participación ciudadana en todas las etapas del proceso de planeación. Para alcanzar este propósito se propone la revisión de los referentes conceptuales, particularmente en lo que hace a la contraposición entre planeación y políticas públicas. Se continúa con los cambios normativos de la gestión pública que introdujo la Constitución Política de la Ciudad, así como el proceso sociopolítico de la que ésta surgió. A continuación, se establecen las principales contradicciones normativas en las que, en vez de la armónica distribución de atribuciones entre poderes y órganos autónomos prevista en la Constitución, se legisla para favorecer la preminencia del Ejecutivo. Se prosigue explicando las razones sociopolíticas de esta orientación, misma que será la causa de que la inercia de las prácticas de gestión y de régimen político heredadas del DF terminen por imponerse a la innovación prevista de la constitución de la Ciudad de México, lo que por hoy se constituye el principal freno a la planeación.
La consulta del Plan General de Desarrollo (PGD) en la Ciudad de México: la disputa entre la legitimación política y la participación ciudadana (2022-2023)
Authors: Morales Guzmán Jesús Carlos
Published: December 2024

El trabajo analiza el proceso de consulta pública del Plan General de Desarrollo (PGD) en dos vertientes: como proceso formal y ejercicio deliberativo en la Ciudad de México. La perspectiva teórica se relaciona con la confirmación de un campo de disputas o controversia que libran los diversos actores urbanos que se articulan y enfrentan a partir de diferentes proyectos políticos o visiones de ciudad. A partir de una metodología mixta se reconstruyen algunos episodios de los enfrentamientos (o disputas) que se han generado entre el gobierno local, las organizaciones sociales y los pueblos y barrios de la ciudad en torno al significado y visiones sobre dicho instrumento. Se argumenta que la consulta formal y como ejercicio deliberativo reflejó no solo la dificultad para integrar la participación ciudadana al sistema de planeación democrática, sino una tensión de fondo entre la orientación neoliberal del gobierno (ciudad global y compacta) y la lucha por los derechos y la reducción de las desigualdades en la Ciudad. Asimismo, el proceso formal mostró la incapacidad de construir una agenda ciudadana plena y su inclusión en el plan de desarrollo; la ambigüedad en la identificación y priorización de los problemas públicos en diversas versiones del documento, así como la omisión en cuanto a las graves violaciones a los derechos en la Ciudad; el déficit en la integración final del Instituto y sus capacidades de coordinación e integración de los equipos técnicos que llevaron adelante el ejercicio institucional. Finalmente, la ausencia de deliberación retrasó la construcción de la legitimidad y autonomía necesaria para la inclusión de las visiones e intereses de los diferentes actores urbanos en el PGD.
Climate-resilient transportation policies for India: Strategies and challenges
Authors: Inumula Krishna Murthy , Tadamarla Anupama
Published: December 2024

The transportation sector in India, which is a vital engine for economic growth, is progressively facing challenges related to climate change. Increased temperature, extreme weather conditions, and rising seas threaten physical infrastructure, service delivery, and the economy. This research examines efforts towards improving the climate resilience of India’s transport sector through policy interventions. Strategies encompass broadening the focus to cover the integration of sustainability, innovative technology deployment, and adaptive infrastructure planning. Multi-sectoral measures are proposed to guarantee longevity, equity and environmental protection. National transport infrastructure will be secured, people will be enabled to move sustainably, and India will take its position in the world economy as a climate-resilient country. Long-term resource management and promoting inclusive governance are critical to agri-transportation systems that can withstand the changing climate.
Niamey: The ages of a city
Authors: Ilyassou Sanoussi , Dandonougbo Iléri , Motcho Henri Kokou
Published: December 2024

Over the last few decades, countries in the South have been undergoing rapid urbanization, as if to make up for lost time. Sub-Saharan Africa is characterized by a very low urbanization rate compared to0 the rest of the world. Although the African continent reached its urban transition in 2015, Niger remains by far the least urbanized country, with a rate of 17%. The city of Niamey is the main urban center, with an estimated population of 1,449,801 hbts in 2023, spread over an area of around 33,100 ha. The aim of this study is to analyze the spatial expansion of the city of Niamey from 1984 to 2023. The main data used in this study are raster images from the United States Geological Survey (USGS), vector data from Open Sources Map (OSM) and GoogleEarth, secondary data from the National Institute of Statistics (INS) and field observation. This study enabled us to conclude that between 1984 and 2023, the city of Niamey underwent very strong spatial expansion. The city grew from 4,690 ha to 33,100 ha, i.e. 28,410 ha absorbed in 39 years, with exceptional growth between 2014 and 2023, when the urban area doubled. Its population has risen from 397,437 at the time of the 1988 general population and housing census to an estimated 1,449,801 in 2023 (INS), an increase of 1,052,364 in 35 years. Between these two dates, population density fell from 87.7 to 43.8 inhabitants/km2, i.e. half that of 1984. This spatial expansion has resulted in unprecedented peri-urbanization.
Contribution of earth bricks reinforced with African locust bean pod powder (Parkia biglobosa) to sustainable construction in Togo: Characterization, formulation, mechanical performance, and recommendations
Authors: Tossim Magnouréwa Josiane , Banakinao Sinko , Samon Sekdja Prosper , Zemo Marie Anita Temgoua , Mavunda Célestin Adeito , Aholou Cyprien Coffi , Ayité Yawovi Mawuénya Xolali Dany
Published: December 2024

In response to the challenges of climate change, this study explores the use of moringa pod powder as reinforcement in the manufacture of compressed earth bricks to promote sustainable building materials. The objective is to evaluate the impact of African locust bean pod powder on the mechanical properties of the bricks. Two types of soils from Togo were characterized according to geotechnical standards. Mixtures containing 8% African locust bean pod powder at various particle sizes (0.08 mm, 2 mm, and between 2 and 5 mm) were formulated and tested for compression and tensile strength. The results show that the addition of African locust bean pod reduces the mechanical strength of the bricks compared to the control sample without pods, with strengths ranging from 0.697 to 0.767 MPa, compared to 0.967 to 1.060 MPa for the control. However, the best performances for the mixtures were obtained with a fineness of less than 2 mm. This decrease in performance is attributed to several factors, including inadequate water content and suboptimal preparation and compaction methods. Optimizing formulation parameters is necessary to maximize the effectiveness of African locust bean pods. This work highlights the valorization of agro-industrial waste, paving the way for a better understanding of bio-based materials and future research for sustainable construction.
O abandono afetivo materno: uma reflexão a partir da doutrina da proteção integral
Authors: Seidel Isabela , Ningeliski Adriane de Oliveira
Published: December 2024

Este estudo se refere ao abandono afetivo materno, demonstrando que o abandono afetivo não é apenas uma prática paterna, podendo ocorrer também por parte das mães. As transformações sociais que moldam a estrutura e a dinâmica das famílias ao longo do tempo, destacando a industrialização, a urbanização e o ingresso das mulheres no mercado de trabalho, embora tenham promovido maior igualdade nas relações familiares, também trouxeram desafios, entre eles a negligência das mães com seus filhos. Com a valorização do individualismo e a busca pela realização pessoal, muitas mulheres têm se afastado do lar, deixando de lado suas responsabilidades maternas, o que pode causar danos significativos ao desenvolvimento emocional e psicológico dos filhos. Esta pesquisa busca refletir sobre o abandono afetivo materno, sob a ótica da doutrina da proteção integral. Para tanto, visa retratar os aspectos mais importantes da doutrina da proteção integral, o abandono afetivo materno e seus reflexos na infantoadolescência. A metodologia de abordagem utilizada é a dedutiva, a partir do pressuposto de que o abandono afetivo materno tem crescido ultimamente e é prejudicial ao desenvolvimento da criança e do adolescente, em ofensa ao que prevê o Estatuto da Criança e do Adolescente. Conclui-se, que o abandono afetivo materno, embora menos discutido, é um problema grave que necessita de maior atenção da sociedade e que, apesar de não haver dados específicos sobre o tema, a visão social que se tem é de que está em crescimento, causando danos no mesmo nível de gravidade que o abandono afetivo paterno.
O papel da moda como traje típico e da propriedade intelectual na preservação do patrimônio cultural
Authors: Lima Briane Luise Pires de , Bueno Mariza Schuster , Guerber Patricia Minini Wechinewsky
Published: December 2024

O presente artigo tem como propósito discutir como a moda, através dos trajes típicos, e as legislações da propriedade intelectual podem ser utilizadas para que o patrimônio cultural seja preservado. Ao investigar a interseção entre a moda e os direitos de propriedade intelectual, este estudo busca explicar de que maneira essas esferas podem contribuir para a salvaguarda e a valorização dos recursos culturais imateriais. O objetivo geral é analisar como a moda e os mecanismos de propriedade intelectual podem contribuir para a preservação e valorização do patrimônio cultural. Dessa forma, os objetivos específicos buscam conceituar o que é a moda, o patrimônio cultural e a propriedade intelectual; examinar também os mecanismos legais de propriedade intelectual e de proteção ao patrimônio cultural disponíveis para a proteção de elementos culturais e por conseguinte identificar exemplos de iniciativas na moda que visam preservar e valorizar o patrimônio cultural, tanto os casos de sucesso quanto os fracassos, para entender os fatores determinantes em cada situação. A metodologia utilizada no presente trabalho é dedutiva, de abordagem qualitativa e analítica e de caráter bibliográfico.
Energy efficiency of waste gasification plants in the national municipal waste management system
Authors: Primus Arkadiusz , Buntner Dagmara , Rosik-Dulewska Czesława , Chmielniak Tadeusz
Published: December 2024

To achieve high levels of municipal waste recovery through a system employing mechanical-biological waste processing technologies, effective management of the over-sieve fraction of mixed municipal waste (preRDF) is crucial. This preRDF cannot be landfilled due to its combustion heat exceeding 6 MJ/kg. Therefore, thermal treatment of waste and subsequent energy recovery become pivotal in the national waste management system, particularly amidst energy crises and fluctuating energy prices. Waste-derived energy can serve as a valuable renewable energy source. To ascertain the true efficiency of the plant in terms of energy, environmental impact, and economics, it is vital to organize the concepts of energy efficiency for thermal waste treatment plants. The energy efficiency of a waste gasification plant should be comprehensively assessed from three standpoints: energy efficiency of thermal waste treatment (i.e., energy efficiency index), energy efficiency of recovering chemical energy contained in waste (actual energy efficiency of the plant), and the efficiency of renewable energy production. A thermal waste processing plant qualifies as a renewable energy source, when it generates electricity and heat from the biodegradable fraction of waste. This article endeavours to determine the potential contribution of chemical energy from the biodegradable waste fraction, relying on preRDF fraction test results..
Research progress on acid mine drainage treatment based on CiteSpace analysis
Authors: Si Meiyan , Zhang Yuntao , Jin Hai , Long Yongliang , Nie Tao , Feng Wei , Li Qingsong , Lin Yichao , Xu Xiaoqian , Wang Chunhua
Published: December 2024

Acid mine drainage has always been of global concern, primarily due to its low pH, high concentration of heavy metals and toxic substances, and serious impact on the surrounding environment and ecology of mines. However, the research progress and hotspots in this field of acid mine drainage processing are still unclear. To better understand the research hotspots and trends of acid mine drainage processing from 2004 to 2023, we used CiteSpace bibliometric software to visually analyze 1142 English-language research articles and reviews from the Web of Science core database. Results indicated that this field has received increas-ing attention from researchers worldwide, especially since 2017. The USA and China stand out as major contributors, yet their international collaboration doesn't match South Africa robust partnerships. Strengthening cooperation with other nations should be a priority for both the USA and China. The University of Quebec and University of South Africa were the most production institution. Vhahangwele Masindi from South Africa was the most active author. The top two core journals in this field were Science of the Total Environment and Water Re-search. Additionally, through keyword co-occurrence, clustering, and burst analysis, it is evi-dent that research on heavy metal mechanisms and resource recovery will be the future re-search hotspots in this field of acid mine drainage. This study provides researchers with an opportunity to understand the hotspots and trends in acid mine drainage research from a bibliometric perspective, and serves as a reference for future studies.
Evaluating of the Relationships between aAverage Particle Size and Microstructure-Mechanical Properties of Materials Produced in Different Compositions using Ultrasonic Method
Authors: Özkan Bilici V. , Yönetken A.
Published: December 2024

Pulse-echo ultrasonic test, which is one of the non-destructive testing methods, was used to measure ultrasonic quantities such as longitudinal velocity (VL), shear velocity (VT) and attenuation coefficient (α) in FeCrMn composites. The corresponding elastic constants were determined depending on the longitudinal and transverse velocity. The aim was to reveal the correlation between the microstructural and mechanical properties of FeCrMn composites and ultrasonic quantities. The effect of adding Cr particles on VL and VT velocities is obviously attributed to the change in elastic and shear modulus of FeCrMn composites. It was found that both VL and VT velocities, Young’s modulus (E) and shear modulus (G), as well as hardness values, changed approximately linearly with increasing Cr content. In this study, samples with different volumetric compositions were produced using the powder metallurgy method. It has been revealed that both the applied method and the increase in the amount of Cr have a significant effect on the velocities of VL and VT. The increase in VL and VT is due to the increase of Cr particles, the homogeneous distribution of Cr, the formation of samples especially at a certain temperature, and the decrease of porosity. As a result of these, a decrease in attenuation values was observed depending on the mean grain size. Elastic constants were found to vary in the same way as ultrasonic velocities. By increasing the Cr content both the hardness values and the shear modulus were improved and a good correlation was observed with the grain size.
The Effect of Barrel Configurations on the Porosity During HVAF Thermal Spray Ni-Based Amorphous Coatings: Numerical Simulation and Experiment
Authors: Wu Nianchu , Li Tingting , Su Xiaotian
Published: December 2024

The relationship between barrel configurations and porosity of a Ni-based amorphous coating (AM) that is fabricated using a high-velocity air fuel (HVAF) process was revealed by both numerical and experimental methods. A computational fluid dynamics model was applied to investigate the gas-flow field and the behavior of in-flight particles with various barrel configurations. It is found that barrel length obviously affects the particle velocity and temperature while it has a slight influence on the particle velocity and temperature. The longer the barrel length (diameter), the higher the flame (particle) velocity and temperature. By analyzing both particle velocity and temperature, the optimal barrel configuration (4E) to achieve low-porosity coatings was predicted. These calculations were experimentally verified by the production of a low-porosity (2.09%) Ni-based AM that was fabricated by HVAF using the predicted optimal barrel configuration.
Effect of NaOH Solution on Mechanical Properties and Morphology of Fly Ash Based Cold-Pressed Geopolymer
Authors: Shee-Ween O. , Cheng-Yong H. , Abdullah M.M.A.B. , Wan-En O. , Yong-Jie H. , Hoe-Woon T. , Jia-Ni L.
Published: December 2024

Cold-pressing method is beneficial in reducing the porosity of geopolymer matrix, but the low liquid volume will result in unreacted aluminosilicate materials. This problem can be resolved by increasing sodium hydroxide (NaOH) concentration. This paper thus investigates the effect of NaOH concentration on the properties of cold-pressed geopolymer. The fly ash was activated by sodium silicate (Na2SiO3) and 10, 12, 14 and 16 M of NaOH solution. The dry mix was compacted with a uniaxial hydraulic press and cured for 7 and 28 days. The specimens were measured by porosity and compressive strength measurements. Scanning electron microscopy (SEM) analysis was performed to determine the microstructure of specimens. The geopolymer was optimized at 14 M NaOH with the highest 28-day compressive strength (109.6 MPa) and lowest porosity (8.1%). The SEM micrographs proved that the geopolymer have a dense and compact microstructure.
The Synthesis of Crystalline, Mono-Phase Copper and Zinc Arsenates (III)
Authors: Behnajady B. , Moghaddam J.
Published: December 2024

This research is part of a continuing effort to synthesize copper and zinc arsenates(III) to use as a zinc dust activator in zinc sulphate solution purification. In this paper, the feasibility of synthesizing crystalline, mono-phase zinc and copper arsenates(III) were investigated. Copper and zinc arsenates(III) were prepared by adding their sulphate solutions into arsenious solution obtained by dissolving As2O3 in NaOH aqueous solution. The structure and crystal lattice of the products and amount of the elements in precipitations were characterized by X-ray diffraction(XRD) and Atomic Absorption Spectrometry(AAS), respectively. Based on the results of XRD in the conditions of NaOH concentration = 1 mol/L, n(OH–)/n(As) = 1:1, n(Cu)/n(As) = 1:2, reaction temperature 90°C and reaction time 8h, a mono-phase crystalline copper arsenate(III) with the chemical composition of Cu(AsO2)2 and tetragonal crystal lattice was synthesized. In these conditions, the yields of arsenic and copper precipitation from the solution were 93.81% and 97.68%, respectively. Based on the XRD results in the conditions of NaOH concentration = 1 L, n(OH–)/n(As) = 1:1, n(Zn)/n(As) = 1:2, reaction temperature 80°C, reaction time 2h and washing pH = 6, a mono-phase crystalline zinc arsenate (III) with the chemical composition of Zn(AsO2)2 and monoclinic crystal lattice was synthesized. In these conditions, the yields of arsenic and zinc extraction from the solution were 77.70% and 46.37%, respectively.
Use of Ultrasound to Identify Microstructure-Property Relationships in (AlN + WC) Fabricated with Electroless Ni Producing
Authors: Özkan Bilici V. , Yönetken A. , Erol A.
Published: December 2024

In order to improve the properties of the materials produced by the powder metallurgy method, first of all, powders (16.59% AlN + 6.63% WC) were coated with nickel (Ni) by electroless method, and then box boriding, which is one of the most widely used surface coating methods, was applied. A composite formed with (16.59% AlN + 6.63% WC)76.7Ni was prepared under the Ar shroud in the temperature range of 1000-1400°C. Pulse-echo technique was used for ultrasonic velocity measurements on Ni coated (16.59% AlN + 6.63% WC) samples. It is aimed to examine the change of physical, mechanical and ultrasonic properties of the obtained ceramic-metal composites depending on different sintering temperatures. In addition, the samples were characterized by mechanical and metallographic examination. The results show that the longitudinal and transverse ultrasonic velocity values and ultrasonic modulus (shear, bulk, Young’s etc.) values increase simultaneously with the increase of sintering temperature. The highest microhardness value was observed in composite samples sintered at 1400°C and its value was 1150.80 Hv. The increased strength is mainly due to grain refinement and strong interfacial bonding between Ni particles and AlN and WC matrix.
Physical Properties and Compressive Strength of Pressed and Cast Fly Ash Geopolymer
Authors: Jia-Ni L. , Yun-Ming L. , Abdullah M.M.A.B. , Hoe-Woon T. , Yong-Jie H. , Shee-Ween O. , Wan-En O.
Published: December 2024

Geopolymers are commonly recognized as sustainable alternatives to OPC and it has broad range of applications. Certain properties of geopolymer such as density are concerned in order to apply in the construction industry. Different densities of geopolymer could be obtained by varying the concentration of the alkaline activator. However, the densities do not differ much. Hence, a different production method of geopolymer can be applied. This study aimed to investigate the physical properties and compressive strength of pressed and cast fly ash geopolymer. The geopolymer samples were prepared by using pressing and casting method. Geopolymer samples without foam addition and with foam addition were prepared in order to achieve different densities of samples. The results demonstrated that the pressed sample has the highest bulk density (2285 kg/m3) whereas the cast sample with added highest ratio of foam has the lowest bulk density (1293 kg/m3). The apparent porosity and water absorption result were inversely proportional to the bulk density result. The densest geopolymer obtained the highest compressive strength (61 MPa) and the lightest geopolymer obtained the lowest compressive strength (7 MPa).
One Part Method for Making Geopolymer Paste using Flocculated Sidoarjo Mud
Authors: Syihabuddin T. , Ekaputri J.J. , Maulana M.A. , Soemitro R.A.A. , Pet rus H.T.B.M. , Chikako F.
Published: December 2024

Some efforts have proposed the utilization of Sidoarjo mud for geopolymer paste. However, the original dry mud in geopolymer concrete showed decreased compressive strength and increased required water. In this paper, the one-part method is proposed to reduce the water in the mixture. First, the mud was chemically flocculated. Then, the dry mud was mixed with fly ash, activated geothermal silicate, and sodium hydroxide mixture in solid form before then the distilled water was added. This reduced the required water to 50% compared to the two-part method. The flocculant sedimented heavy metal that resulted in higher compressive strength at a later age. At 28 days, dry flocculated mud showed higher compressive strength than the original dry mud, with a compressive strength of 13 MPa and 11 MPa, respectively. This is because of the increase of silica, alumina, and iron content from 70% in dry LUSI to 75% in dry flocculated mud.
Experimental Characterization of Banana-Palm Fiber Reinforced Hybrid Polymer Composite
Authors: Selvam B. , Balamurugan G.M. , Gebrehiwot B.
Published: December 2024

Composite materials are synthesized by using natural cellulose fibers with matrix, due to their improved properties. In this work, banana and palm fibers are treated with 2% and 8% NaoH, respectively, for the removal of lignin and hemicelluloses. The hybrid composite was fabricated by using epoxy resin as the matrix and both the fibers as reinforcement through the hand lay-up method. By varying the banana and palm fibers in the range of 5-15% wt. and 7.5-22.5% wt. in the composite of 20% wt. and 30% wt. reinforcement, respectively, The composite consists of 5/15% wt. treated fibers, having more influence on compressive strength of 222.46 MPa and flexural strength of 535 MPa. However, 7.5/22.5% wt. treated composite has a higher impact resistance of 14.6 J and 10/10% treated composite gained a higher water absorption percentage weight of 1.16% at 216 hours. From the experiment, the composite with 5/15% wt. fibers of 20% wt. reinforcement and 80% wt. epoxy is suitable for making kitchen slabs.
Effect of Nb and Zr Alloying Additives on Structure and Properties of Ti-Ta-Nb-Zr Alloys for Medical Applications
Authors: Dercz G. , Matuła I. , Prusik K. , Zając J. , Szklarska M. , Kazek-Kęsik A. , Simka W.
Published: December 2024

This work investigated two titanium-based alloys with a constant tantalum content and variable contents of alloy additives – niobium and zirconium. The Ti-30Ta-10Zr-20Nb (wt.%) and Ti-30Ta-20Zr-10Nb (wt.%) alloys were obtained using a combination of powder metallurgy and arc melting methods. The influence of alloying additives on the structure and properties of the Ti-Ta-Nb-Zr system was studied using, among others: X-ray diffraction and scanning electron microscopy. The X-ray diffraction confirmed the single-β-phase structure of both alloys. In addition, the microscopic analysis revealed that a higher amount of zirconium favoured the formation of larger grains. However, the microhardness analysis indicated that the alloy with the higher niobium content had the higher microhardness. Importantly, the in vitro corrosion study revealed that the addition of niobium promoted the better corrosion resistance of the investigated alloy.
Enhanced Mechanical Properties of Mg-8Li Dual-Phase Alloy Processed by Friction Stirring Versus Hot-Extrusion
Authors: Zhang Li , Li Nan
Published: December 2024

The microstructure evolution, texture and tensile properties of the Mg-8Li dual-phase alloys processed by hot-extrusion and friction stir processing were investigated. It was found that the friction stir processing was more advantageous when compared with hot-extrusion in achieving the superior mechanical properties. The tensile strength, yield strength and elongation of the as-FSPed alloy reached 235.4 MPa, 185.3 MPa and 35.6%, respectively. The outstanding strength-ductility combination of the ­as-FSPed Mg-8Li alloy was ascribed to refined grains, weakened texture and formation of high-fraction high angle grain boundaries.
The Effect of Palm Char Properties on Malaysian Ilmenite Ores by Carbothermal Reduction
Authors: Nasrun N.A. , Yunos N.F.M. , Idris M.A. , Halif N.A. , Nomura T.
Published: December 2024

To identify the mineral grade ore, two distinct Malaysian ilmenite ores (FeTiO3) from different placers deposits were examined. The sources of ilmenite ore were the Kinta Valley in Perak and the Langkawi Black Sand Beach in Kedah. Both of the ores were reduced by palm char as a sustainable carbon reductant. The study examined carbon characteristics and phase transitions following carbothermal reduction at 1550°C. Prior to the studies, the reductant palm char was characterized by XRF, BET surface area measurement, SEM, and ultimate with proximate analyses. It is shown that the palm char had low moisture (4.10 wt.%) and high fixed carbon (75.40 wt.%). The high carbon content, volatile matter, and porous structure of palm char played a significant role in the gas generated during the carbothermal reduction of ilmenite ores. Carbothermal reduction of both ilmenite ores with palm char-produced rutile, iron, titanium carbide, and pseudobrookite. The XRF analysis exhibits the existence of 18.41 and 35.76 wt.% of Fe and TiO2 respectively in Perak ilmenite ore. While Langkawi ilmenite ore shows 9.28 and 22.72 wt.% of Fe and TiO2 respectively.
The Effects of CaO and MgO on Thermal, Mechanical and Optical Properties of Porcelain Tiles by Utilizing Blast Furnace Slag
Authors: Aydin T. , Sari H.
Published: December 2024

In this study, the Blast Furnace Slag (BFS) of Zonguldak Eregli Iron and Steel Factories was used as a recycling raw material for the porcelain tile samples. A kind of clay with high MgO content was also used in the porcelain tile recipes. Maximum 10% of BFS was used instead of Na-feldspar. Sintering temperature for all samples was 1205°C for 50 minutes in the industrial roller kiln. Technological properties such as shrinkage, water absorption, colour measurement, and flexural strength were investigated as well as sintering properties and microstructures of the green and the sintered samples. As a result of the study, the addition of BFS did not adversely affect the technical properties of porcelain tile bodies. Particularly, the addition of BFS up to 3% contributed to an increase in flexural strength, and whiteness values of all samples increased because of the formation of anorthite and diopside compared to the reference body. The phase transformations and crystal formations such as anorthite and diopside resulted in a decrease in the ﬁring shrinkage. Although the anorthite formation and diopside formation in the investigated samples had an adverse effect on condensation, it was found that they showed similar sintering behaviours compared to the reference body. This study showed that an industrial waste material can be converted into an environmentally friendly raw material that can create added value and provide energy efficiency.
Joining UFG Copper by Means of the W2Mi Machine
Authors: Morawiński Ł. , Jasiński C. , Goliński J. , Chmielewski T.M.
Published: December 2024

Joining metals with ultra-fine grains (UFG) is very difficult. UFG metals have a grain size of less than 1 µm. Exceeding the recrystallization temperature causes the growth of ultra-fine grains and degradation of the material’s mechanical properties. The process temperature is influenced by the amount of energy supplied to the joint, which depends on the power and time. Conventional machines are not adapted to effectively conduct the process in extremely short friction times. For this reason, this article presents the welding process on the W2Mi prototype machine. The design of this machine allows the joining of UFG metals in less than 100 ms. UFG material produced using the hybrid SPD (Severe Plastic Deformation) process from technically pure CW004A(Cu-ETP) copper was used for welding tests. The joint obtained on the W2Mi machine did not show any significant degradation signs of mechanical properties. At the same time, an increase in microhardness in the joint area by approximately 4% was noticed. The obtained results prove that the process of joining UFG metals was successfully carried out.
A Low Temperature Calciothermic Reduction Approach for the Synthesis of LaB6 Powders
Authors: Sadhasivam M. , Usmaniya M. , Berchmans L.J. , Sanakaranarayanan S.R. , Kumaresh Babu S.P. , Vijayaragavan G.
Published: December 2024

In this work, we report the synthesis of a polycrystalline LaB6 powders with a uniform morphology by a low-temperature metallothermic reduction route using calcium as a reductant. The processing methodology and heat treatment parameters are optimized based on thermodynamic estimates in order to favour the reaction kinetics and for complete formation of LaB6 powders with highest purity. The synthesised powder was subjected to comprehensive characterization studies. X-Ray Diffraction (XRD) revealed the complete formation of LaB6 compound without any traces of reactants. Scanning Electron Microscopy (FE-SEM) along with chemical mapping shows the morphology and elemental distribution of LaB6 powder. X-Ray Photoelectron Spectroscopy (XPS) results show the futuristic peaks with photon energies that are assigned to the core levels of the La and B without significant impurities whereas the Fourier transform infrared (FTIR) spectrum indicates an apparent presence of La-B bonds at 1045.4 cm−1, 585.5 cm−1, and at 463.1 cm−1.
Evaluation of Peel Ply Effectiveness in Controlling Mould Release Agent Contamination of Epoxy/Carbon Fibre Composite Laminate Surfaces
Authors: Kuppusamy R.R.P. , Zade A. , Sridhar Babu B.
Published: December 2024

The peel-ply effectiveness in controlling the mould release contaminations of resin transfer molded (RTM) RTM6/G0926 epoxy-carbon fibre composite laminate surfaces have been examined. X-ray photoelectron spectroscopy (XPS) was employed to evaluate the extent of transfer of mould release agents and other surface contaminants of RTM composite laminates at semi-cured and fully cured states. Fully cured and 55% semi-cure degree of RTM composite laminates were prepared using polyester and diatex peel plies. The effectiveness of polyester and diatex peel plies were evaluated by comparing the amount of Frekote mould release contaminants present in the laminate surfaces processed with and without peel plies. The XPS results shows that the composite laminates processed without peel plies at different cured states exhibit uniform contamination with Freakote calcium metal ions. At the comparisons of polyester and diatex peel plies, the diatex peel ply performs better in controlling the surface contaminations.
An Exploratory Study of the Surface Integrity of Various FRP Composites in Face Milling Operation
Authors: Prasanth I.S.N.V.R. , Chandra Shekar K. , Raju V.P. , Sridhar Babu B.
Published: December 2024

The use of glass, carbon and hybrid /glass/carbon epoxy polymer composites is widely used in the automotive, manufacturing and aerospace sectors. Milling is a secondary production process in which the final shape of the product is produced with the desired shape and high dimensional accuracy. The objective of this study is to enhance our knowledge of the machinability properties of composite materials in the secondary manufacturing industry. In this research study, performing face milling operations with different tools on bidirectional (BD) glass, unidirectional (UD) glass, carbon/epoxy, and glass/carbon/epoxy (hybrid epoxy) polymer composites. This experimental work derives conclusions that contribute to the improvement of the milling process for better surface quality. Taguchi’s L16 Design of Experiments (DOE) and Analysis of Variance (ANOVA) are used to determine the effect of tool type, speed of spindle, rate of feed, cut depth on surface roughness and delamination factor. And it was concluded that glass/carbon hybrid epoxy polymer laminates showed improved surface quality when milled with a Poly Crystalline Diamond (PCD) tool at parametric combinations of rate of feed is 300 mm/min, speed of spindle is 1000 rpm, and cutting depth is 0.5 mm. In addition, the experimental results of the scanning electron microscope examination were also verified. And found excellent machined surface quality and least damage with the above optimal process parameter combinations.