Material Aspects Research Articles

Reactive powder concrete beam design using a mathematical software to reduce costs

AbstractReactive powder concrete is widely recognized for its remarkable mechanical characteristics and resilience, rendering it an ideal option for structural uses that include heavy loads. However, the intricate interaction of numerous material and geometric aspects makes constructing reactive powder concrete beams extremely difficult. By using MATLAB to provide an optimized design framework for beams, this research tackles these issues. Particle swarm optimization and evolutionary algorithms are two of the advanced techniques used in the study to solve the optimization problem. It also includes constraints other one as structural requirements and material limitations. Results demonstrate that MATLAB-based optimization facilitates effective design, lowering costs and material consumption, with potential for more applications in the building sector.

Viscoelastic negative stiffness metamaterial with multistage load bearing and programmable energy absorption ability

ABSTRACT The mechanical properties of negative stiffness (NS) metamaterial could be customized and tuned in a wide range for various requirements, achieving programmable performances by the design from the aspect of structure and material. This work investigates the viscoelastic NS metamaterial based on double curved beams using a combined approach of experiments, simulations, and analytical modeling with an emphasis on multistage loading bearing and programmable energy absorption ability. Numerical simulations are first implemented based on the finite element models of three types of metamaterial cells, which provide comparisons of load bearing and energy absorption properties. Further, the effects of geometric parameters of multistage metamaterial element and the mechanisms are analyzed. An analytical discrete model is then innovatively developed to provide straightforward understandings of the geometric effects and reveal the role of viscoelasticity by examining the instantaneous loading responses and rate-dependent behaviors. Experimentally, we fabricate the metamaterial samples using 3D-printing technique and perform compression tests to validate the properties based on different boundary conditions, loading rates and cyclic loading and unloading. Results of this work show the potential of wide programmable room for mechanical properties through structure and functional material design, such as multistage load bearing capacity and energy absorption ability.

Nickel Dynamics Switches the Selectivity of CO2 Hydrogenation

AbstractThe Reverse Water Gas‐Shift reaction (CO2+H2 CO+H2O) allows to balance syn‐gas under industrial conditions. Nickel has been suggested as a potential catalyst but the temperature required is too high, more than 800 °C, limiting practical implementation but when lowering the temperature methanation occurs. Simulations via Density Functional Theory on well‐defined surfaces have systematically failed to reproduce these experimental results. But under reaction conditions, Ni surfaces are not static and DFT models coupled to microkinetics show that low temperatures (high CO coverages) drive the generation of Ni adatoms that are the active sites for methanation. At higher temperatures, the adatom population decreases, and the selectivity towards CO increases. Thus the mechanism behind the selectivity switch is driven by the dynamics induced by reaction intermediates. Our work contributes to the inclusion of dynamic aspects of materials under reaction conditions in the understanding of complex catalytic behaviour.

Towards Sustainable Products and Services: The Influences of Traditional Costumes in Promoting Sustainable Fashion

Recent research in Sustainability has gained increasing attention within the past years, particularly regarding methods and approaches for designing sustainable products and services to address environmental and societal challenges. However, there has been limited exploration of incorporating cultural materials into the design process, which could enhance the cultural sustainability of products and services. This article aims to investigate the potential of integrating traditional royal costumes into fashion design to foster sustainability values and behaviours in contemporary society. A descriptive study focused on the Nhat Binh robe; a formal dress worn by noblewomen of the Nguyen Dynasty (1802–1945). The findings reveal that this traditional costume is rich in visual elements, offering a wealth of inspiration for fashion designers. However, existing products and services have yet to fully leverage the emotional and visual aspects of this unique cultural material. To creatively and sustainably preserve and promote traditional cultural values, this study proposes a model for incorporating traditional cultural materials into fashion design through co-design activities. This model emphasizes close collaboration between designers, artisans, and fashion consumers, with the goal of safeguarding traditional cultural values while advancing sustainable fashion. By fostering collaboration among them, the model has the potential to encourage a sense of ownership and emotional connection to the products, enriching consumer experiences. It not only addresses existing gaps in the use of cultural elements in fashion design but also positions designers to play a pivotal role in the future of sustainable fashion.

Environmental Impact Assessment System: Case Analysis of Existing Legal Disputes

Abstract: Environmental Impact Assessment (EIA) refers to the process of assessing the possible impact of planning activities on the environment. This paper contends that the current international legal framework does not adequately delineate the activation criteria for EIA and overlooks the significance of international collaborative duties that come into play when sovereign states embark on the initiation and execution of EIA processes. Only in relation to the general principles of international law can the nature of the EIAs obligation be comprehended. When dealing with cross-border damage, the requirement for due diligence is complemented by an implicit responsibility to collaborate. This latter obligation arises under identical situations as the due diligence requirement, particularly in response to 'the likelihood of significant environmental damage,' and thus, it needs to be satisfied by the national government under equivalent circumstances. This paper argues that the courts interpretation of environmental impact assessment is incomplete which is reflected in two aspects: (1) the ambiguity in the court's grasp of the EIA threshold's unpredictability. The International Court of Justice fails to clarify the criteria for establishing a 'substantial environmental risk'. (2) The court's oversight in considering the duty to collaborate could result in an overemphasis on the material aspects of EIA-treating it merely as a technical instrument. By reintegrating the cooperation duty, a more balanced perspective on the procedural elements of EIA could be achieved. Delving into strategies to rectify these two deficiencies and obtaining a holistic insight into the International Court of Justice's approach to EIA will yield substantial implications and relevance for future EIA-related endeavors.

Modeling the effect of superconductor properties on sensitivity and responsivity of superconducting nanowire single photon detector

Superconducting nanowire single photon detector (SNSPD) is a leading candidate for applications requiring the fundamental limit of light detection at high detection rates. While SNSPD technology employing nanowires from conventional low temperature superconducting detectors is mature with several commercial solutions, other material options with higher transition temperature approaching liquid nitrogen with faster signal responses are actively being explored. In this context, we develop a comprehensive model that predicts the final potential response from an SNSPD incorporating several physical and material aspects. A phase diagram of photon detection is developed that describes the latching phases and the photon sensitivity as a function of biasing current and temperature for both low temperature and high temperature superconductors. On the one hand, while low temperature superconductors are observed to be more sensitive than high temperature superconductors (HTSs) under any given biasing condition, a biasing window for a single photon detection with HTS nanowires is identified. On the other hand, HTS nanowires demonstrate three orders of magnitude faster response times than the low temperature superconductor nanowire at the same biasing condition, making it uniquely suited for several practical applications.

Pengembangan Media Puzzle Interaktif untuk Pengenalan Huruf pada Anak Usia 5-6 Tahun di Taman Kanak-Kanak

This research aims to develop interactive puzzle-based learning media that is specifically designed to introduce letters to early childhood in Kindergarten Negeri Madani. Conventional learning media are considered less interactive in the letter recognition process, while visual- and play-based approaches have proven to be more effective for children. This research is a type of Research and Development (R&D) research with a 4-D development model (four-D model). This model consists of 4 stages of development including Define, Design, Develop, Disseminate. This media was developed systematically and tested for validity and practicality using a questionnaire. The results of the validity test reached 87.17% for the material aspect and 86.11% for the media aspect, while the practicality test achieved an average score of 81.25%. This interactive puzzle media is proven to be able to increase children's interest in learning letters with a fun approach and support their motor and cognitive development

The Relevance of Determining A CSR Program Based On SDGS: Management Perspective

Sustainability Development Goals (SDGs) are very important for companies in achieving their goals. This research aims to determine management's perspective in integrating the SDGs concept which is reflected in the preparation of the company's CSR program. This research uses a qualitative method through case study approach. This research found that PT KIE carried out several program priorities for sustainability based on material aspects. There is alignment of CSR programs with sustainability goals and there are some that are not included in the Sustainability report. Furthermore, there are two things to measure integration within the company, namely linking sustainability to the company's vision and mission and relationships with company partners and government, so society benefits can increase value for stakeholders. PT KIE has reported a separate sustainability report from the company's annual report. Monitoring and evaluation reports are needed to support the company CSR programs.

RESONANT REVERBERATIONS: MATERIAL INFLUENCE ON SOUND QUALITY IN PERCUSSION INSTRUMENT DESIGN AND PERFORMANCE

This paper is concerned with an in-depth investigation into the relation between material selection and sound quality of percussion instruments, arguing about the various aspects of materials influence on acoustic properties, vibrational behavior, and timbral characteristics. The ability that material properties have on design, performance techniques, pedagogical practice, and further research is made explicit through the complete experimental analysis, recommended here, covering comparative studies, acoustic measurements, modal analysis, expert evaluation, and field studies. Our results show the great degree by which material properties shape sound production, resonance, and expressive potential in percussion instruments, giving valuable insights for designers, manufacturers, performers, educators, and researchers. With careful material choices, adjustments of techniques of performance, teaching techniques informed by principles from science, and interdisciplinary collaborations building, we can continue the evolution of the art and science of percussion instrument making and performance practice toward bringing ever-richer musical experiences and cultural exchanges all over the world.

On the Way to Heaven: Memorial Benches, State Integration, and the Coming of Religion Among the Kulung Rai (Nepal)

Alongside guiding the departed on a ritual journey to their place and time of origin, the Kulung Rai of Nepal have added the construction of stone memorial benches along the pathways to honour their deceased. However, both the representations and material aspects of the deceased and the pathways associated with these memorial constructions and ritual techniques differ. I delve into the past to reconstruct the reasons and conditions for the emergence of these benches, arguing that they are linked to substantial changes resulting from the gradual integration of the Kulung into the Nepalese state. This integration fostered the development of Hindu and Buddhist ideas, materialised in the form of these memorial benches. Consequently, I establish a connection between the arrival of the state, the expansion of pathway and road, and religious practices among the Kulung.

Artificial intelligence and the digitalization of finance in Latin America: evidence from Brazil

ABSTRACT For decades, the data-centric digital circuits of global finance have been driving financial markets toward algorithmic management. The penetration of algorithms into finance dates back to the 1980s, well before becoming a significant trend in Internet and social media companies. AI is now considered the new frontier of this process. This paper examines Brazil, the most important financial center in Latin America, as a case study to explore Machine Learning applications in capital markets, providing new evidence on the penetration of automated trading systems in the region. Grounded in a historical overview of the digitalization of capital markets in Brazil, the paper draws on the STS definition of infrastructures and the political economy of digitalized finance to analyze AI as an emerging financial infrastructure. Beyond its physical and material aspects, this approach also addresses how digitalization and AI relate to financialization and the emergence of new financial risks.

COVID time: Temporal imaginaries and pandemic materialities.

Since the advent of the COVID-19 pandemic, several ways of understanding time have emerged: what we may call 'COVID time'. Based on 40 qualitative online interviews in 2022 with Australians living across the continent, this article examines how people situated themselves and COVID-19 in historical time. It further explores how material aspects, place and space (or "pandemic materialities") factored into lived experiences and temporal imaginaries. We focus on how time-related concepts such as synchronisation and the definition of crises and events are interrelated in the participants' understandings of COVID as either over or a continuing crisis. The sociomaterial dimensions that served to alert people to risk and encourage them to engage in preventive action are identified as ways in which COVID time was experienced, remembered, understood and imagined. While some respondents claimed that the present moment was 'post-COVID', for others, the pandemic was far from over in 2022 and indeed stretched into the future. We use a sociomaterial lens to show how respondents portray the 'temporal technologies' and 'objectifications' of the event of COVID-19-the tangible materialisations of its temporal status as either relegated to the past or continuing as a mode of present and future crisis.

Application of machine learning algorithm and Carrera unified formulation in thermal buckling analysis of a functionally graded graphene origami enabled auxetic metamaterial sandwich plate with an auxetic concrete foundation

This study presents a comprehensive thermal buckling analysis of sandwich plates composed of functionally graded graphene origami-enabled auxetic metamaterial (FG-GOEAM) face sheets on an auxetic concrete foundation, using Carrera’s unified formulation (CUF) as the theoretical framework. FG-GOEAM materials are emerging as advanced composites, combining exceptional mechanical resilience, tunable auxetic behavior, and high thermal stability, making them suitable for extreme environments. By employing CUF, a powerful and adaptable modeling approach, this work accurately captures the complex mechanical interactions within the FG-GOEAM sandwich structure under thermal loads, incorporating both material gradation and auxetic properties. To further enhance the precision and efficiency of this thermal buckling analysis, a deep neural network (DNN) is developed as a machine learning algorithm to predict critical temperature differences, based on a dataset generated through mathematics simulation. The DNN model demonstrates excellent predictive capability, validated by close alignment between its estimates and CUF results, thus reducing computational costs while maintaining high accuracy. Parametric studies are conducted to assess the effects of material gradation, aspect ratios, and foundation properties on thermal buckling performance. The results highlight the superior thermal stability of FG-GOEAM structures and the potential of DNNs to serve as reliable, computationally efficient tools for advanced structural analysis. This study provides a novel, integrated framework for high-fidelity thermal buckling prediction in complex auxetic composites, paving the way for broader applications in engineering fields requiring lightweight, thermally stable structures.

Investigation of the melting and solidification processes of a phase change material in cylindrical annular enclosures: A parametric study for energy densification in hot water tanks

The present study focuses on the analysis of the effect of the phase change material (PCM) cavity size on the melting and solidification processes for application to thermal energy densification in a hot water tank through latent heat thermal energy storage in cylindrical annular cavities. A 2D axisymmetric composite geometrical pattern is considered, formed by a phase change material surrounded by a conductive and an insulating material. A parametric study is conducted on the phase change material cavity size, and the results are presented using non-dimensional numbers: Fourier number, Rayleigh number, and aspect ratio. Two approaches have been developed based on local and global analyses. The local one showed the predominance of the conductive or convective heat transfer process concerning the influence of the phase change material size, and thus the Rayleigh number, on the evolution of the solid/liquid interface and streamline shapes. The global one allowed correlations for melting and solidification Fourier numbers with respect to the Rayleigh number and aspect ratio to be built from simulation data. Two parameters for each process have been identified and defined from the present study: the critical Fourier number and the aspect ratio constant. The critical Fourier number corresponds to the maximum Fourier number that the phase change material needs to achieve for a melting or solidification process. The aspect ratio constant provides information on the phase change material aspect ratio value where the Rayleigh number no longer influences the process. In the case of the melting process, this parameter is an indication that convection has reached a maximum intensity and no longer influences the process. Finally, this study proposes a suitable aspect ratio for optimizing the melting process: 19.32, and another for optimizing the solidification process: 16.29.

Evaluation of practicality of wireless charging for electric vehicles in the next 10 years

As the electric vehicle market is expanding rapidly due to the need for sustainable development; a solution is needed to deal with current problems related to electric vehicles, this includes relatively limited driving range, relatively lack of charging spots during busy season, and the inconveniences of plug-in charging, such as dealing with cables. Therefore, wireless charging technology capable of charging electric vehicles while they are in motion becomes a potential solution. Assessing whether this technology will be mass-applied in the future is crucial. Given the limited current research that evaluates the practicality of wireless charging technology for electric vehicles with a time scale, this article aims to assess the aspects of safety, cost, efficiency, materials, user acceptance and other factors to determine the likelihood of making wireless charging practical for electric vehicles in the next decade. Furthermore, by distributing questionnaires to electric and gasoline car owners to gather participants’ opinions and expectations on wireless charging for electric vehicles, statistical analysis of the questionnaire results; interview with a professor at Shanghai University who is an expert in magnets and electricity, conducting secondary research, this article concludes whether wireless charging technology for electric vehicles can be implemented in the decade or not. As an impact, this article includes a time scale by conducting an evaluation instead of implicitly mentioning the time scale.

Improving Critical Thinking Skills of Elementary Students Through Science Learning with Interactive Teaching Materials and Problem Based Learning

This study aims to evaluate the effectiveness of interactive multimedia-based learning with Problem Based Learning (PBL) model in improving critical thinking skills of elementary school students in Natural and Social Sciences subjects. This research uses a development method with quantitative and qualitative approaches. The results of validation from the aspects of material, media, and language showed high ratings, and the product was declared practical by teachers and students. Students were actively involved in learning, and the results of statistical analysis showed significant differences between the control group and the experimental group in learning activities. This shows that this method is effective in improving students' critical thinking skills. Nonetheless, this study has limitations in terms of generalization of the results. Future research is expected to expand the scope of the study and consider additional factors for the development of more effective learning methods.

Material Aspects of Thin-Film Composite Membranes for CO2/N2 Separation: Metal-Organic Frameworks vs. Graphene Oxides vs. Ionic Liquids.

Thin-film composite (TFC) membranes containing various fillers and additives present an effective alternative to conventional dense polymer membranes, which often suffer from low permeance (flux) and the permeability-selectivity tradeoff. Alongside the development and utilization of numerous new polymers over the past few decades, diverse additives such as metal-organic frameworks (MOFs), graphene oxides (GOs), and ionic liquids (ILs) have been integrated into the polymer matrix to enhance performance. However, achieving desirable interfacial compatibility between these additives and the host polymer matrix, particularly in TFC structures, remains a significant challenge. This review discusses recent advancements in TFC membranes for CO2/N2 separation, focusing on material structure, polymer-additive interaction, interface and separation properties. Specifically, we examine membranes operating under dry conditions to clearly assess the impact of additives on membrane properties and performance. Additionally, we provide a perspective on future research directions for designing high-performance membrane materials.

Physical and psychological impact of HIV/AIDS toward youths in Southwest Ethiopia: a phenomenological study

BackgroundYouths with HIV/AIDS encounter a variety of unique challenges that impact their physical, mental, emotional, and social well-being. These challenges and experiences differ across settings, populations, cultures, and the broader socio-economic and political contexts. This study focuses on exploring the life challenges, experiences, and coping mechanisms of youths living with HIV/AIDS in public hospital facilities in southwest Ethiopia.Methods and study approachThe study was conducted in two regional states of Ethiopia. Using a phenomenological study approach, researchers focused on purposefully selected youths living with HIV/AIDS in public hospital facilities. Data were gathered through life history and in-depth interview techniques, delving deeply into the participants’ lived experiences and feelings about the challenges of living with HIV/AIDS. The study population consisted of youths with HIV/AIDS who were currently using antiretroviral medication in two selected public hospitals. A total of 12 participants were employed and completed the study.ResultsThe findings indicated that youths with HIV/AIDS face complex life challenges, influenced by psychological, emotional, and social factors. These intertwined challenges impact their self-management, treatment adherence, and ability to create and maintain healthy social relationships and roles. Many youths avoid social interactions and do not seek the necessary social support, believing they are unworthy of respect and care. Consequently, they may live in despair and constant fear of rejection, lacking the social support they desperately need. Substance abuse is prevalent among these youths due to the psychosocial, biological, emotional, and material aspects of their experiences.

Canva-Based Animation Comic Video Media in Informatics Learning

This study aims to develop Canva-based animated comic video learning media that are valid, practical, and effective for Informatics in Grade VIII at SMP N 14 Padang. The research adopts a Research and Development (R&D) approach, applying the 4D model—Define, Design, Develop, and Disseminate. Primary data were collected from validators, teachers, and students, with descriptive and inferential analysis used to evaluate media validity, practicality, and effectiveness. Results show the media to be valid, scoring 0.963 for media and 0.975 for material aspects. The media is also highly practical, with teacher ratings at 97.04% and student ratings at 93.14%. Effectiveness is indicated by a Gain Score of 0.69 (medium category) and a significant improvement in student learning outcomes, as confirmed by t-test results (Sig. 2-tailed = 0.000; tcount > ttable). The findings confirm that Canva-based animated comic videos significantly enhance student learning outcomes over conventional methods.

The Paradoxical Influence of Hydrothermally Treated Zeolites on the Hydrocarbon Pool Mechanism.

Understanding the mechanistic intricacies of hydrothermally treated zeolite is crucial for valorizing any oxygen-containing renewable feedstocks (e.g., methanol, carbon dioxide, biomass). Additionally, the regeneration of deactivated zeolite catalysts under oxidative conditions, akin to hydrothermal treatment, is essential in industrial processes. While research in this area has predominantly focused on characterizing steaming-induced physicochemical changes in zeolite, their ultimate impact on the organic reaction mechanism governed by the hydrocarbon pool dual-cycle mechanism remains unclear. To bridge this knowledge gap, this study investigates the effect of steamed zeolite on the organic reaction mechanism during the industrially significant methanol-to-hydrocarbons process. We achieved this objective by strategically integrating catalytic and control experiments over the pristine and steamed zeolites and their advanced characterization, including under operando conditions, XRD structural refinement, and using "mobility-dependent" solid-state NMR spectroscopy. This multimodal characterization approach was instrumental in elucidating elusive mechanistic information in the dual-cycle mechanism, shedding light on phenomena such as the unchanged ethylene selectivity despite decreasing aromatics selectivity, while ethylene could solely be derived from arene-based reaction intermediates. This study could improve the process efficiency in zeolite catalysis by connecting steaming-induced changes in the organic reaction mechanisms with inorganic material aspects.