ARPHA Preprints
Not a member yet
49208 research outputs found
Sort by
Organic Dye-Polluted Water Treatment Using ZnO Nanocatalysts
No full textOne of the purposes of this work was to synthesize ZnO photocatalysts with nanodisk and hollow microsphere morphologies using pyrolytic technology. Another purpose was to investigate their photocatalytic activity for the degradation of the organic dye, methylene blue. The nanomaterials were synthesized using Zn, ZnO, and NH4Cl powders as sources. After heating at temperatures above 195°C, NH4Cl decomposed, producing gaseous HCl. It reacted with Zn and ZnO, generating volatile ZnCl2 precursors, which then interacted with residual gases to produce ZnO nanomaterials at the substrate surface. The hexagonal ZnO nanodisks with an average thickness of 70 nm were synthesized at 320°C, while the several micrometer-sized hollow microspheres were produced at 400°C. Both nanocatalysts were utilized for the degradation of an aqueous methylene blue solution under UV irradiation. The ZnO nanodisks decolorized 96 % of the dye within 80 minutes. ZnO hollow microspheres degraded only 87% of the methylene blue solution under the same experimental conditions
Designing for Social Innovation: Apps as a Tool for Co-Creation
No full textA shared understanding of active participation of many urban actors is necessary for a socially sustainable urban environment. This study explores how various urban stakeholders including government agencies, city collectives, citizens, academic institutions, and businesses co-create by leveraging their unique skills and exchanging work and knowledge via an online platform in order to foster social innovation at urban scale. The present research hypothesizes that establishing a participatory mobile application enabling city inhabitants to actively engage and assume shared responsibilities in urban processes can strengthen the sense of belonging of citizens. The design research methodology employed in this study is rooted in the context of co-creation and participatory design. The study is structured around the hypothetical development of the Give a Hand mobile application, a participatory platform designed to make education, health, culture, and art services more accessible for everyone. By enabling participation and co-creation among city inhabitants, the platform aims to optimize public service delivery, saving both time and resources as well as to achieve more inclusive urban environments. More importantly, this platform facilitates urban value creation through mechanisms of volunteering and donations, contributing to the enhancement of the public services. This conceptual framework also helps us understand how designers serve as social innovation facilitators by developing community-driven, inclusive platforms for public service delivery and engagement. The practical implications of this study provides a sustainable network, fostering a stronger sense of belonging among the citizens. By incorporating social networking features, the app facilitates communication, collaboration, and the creation of new community networks, thereby enhancing active participation and contributing to the overall social fabric of the city. The results show that digital platforms can serve as scalable instruments for participatory governance when they are created using the concepts of social innovation and co-creation. The conceptual mobile app provides a flexible and transparent framework for cooperation between corporations, colleges, citizens, and public agencies
Architect’s Perspectives on the Planning Process in Building Projects: The Case of the Maritime Faculty of the Mersin Chamber of Maritime Commerce
No full textThis study explores the architectural planning and implementation processes of the maritime faculty building of the Mersin chamber of shipping from the perspective of the project’s architect. It begins by addressing the unique spatial and functional requirements of maritime education, emphasizing the critical role of such institutions in shaping architectural design strategies. The research traces the project's development from the conceptual design phase through to its realization, evaluating key factors such as sustainability, aesthetics, technological integration, ergonomics, and functional performance. The scope includes an in-depth analysis of specialized training spaces within maritime faculties—such as simulation rooms, laboratories, and training pools—within the framework of architectural design criteria. In this context, the study evaluates the design process and outcomes of the Mersin chamber of shipping maritime faculty building, focusing on the architect’s experiences and the building’s functional effectiveness. The methodology consists of a comprehensive literature review, on-site investigations, development of the building’s colophon, spatial analysis, and a semi-structured interview with the building’s architect, Kaya Arikoğlu. The interview was conducted using a SWOT (strengths, weaknesses, opportunities, threats) analysis framework, enabling a systematic evaluation of the project's internal and external dynamics. Through this multi-faceted approach, the study identifies the strengths and limitations of each stage in the architectural planning process and reveals the final architectural configuration of the project. Moreover, it proposes a set of strategic recommendations and a conceptual roadmap to guide future projects through both design and execution phases. This research highlights the importance of designing sustainable, functional, and pedagogically-aligned environments in the context of maritime education. Findings suggest a direct relationship between the architect’s decision-making process during the planning phase and the subsequent performance of the completed building. The study aims to contribute to the enhancement of educational architecture by offering insights and practical guidance for future architectural endeavors
Effect of Blasting Parameters on Rock Size Induced by Fragmentation in Quarries: A Case Study
No full textThe blasting process in quarries and open-pit mines plays a very important key to achieving optimum performance from the mining company's technical and economic point of view. The magnitude of rock fragmentation is a crucial factor from an economic standpoint in any surface mining operation. The size of rock fragments directly affects drilling, blasting, loading, secondary blasting, and crushing expenses. However, the large number of parameters involved makes it difficult to control this operation. A number of studies have shown the benefits of taking into account all the parameters that affect the results of blasting. In particular, this study has highlighted the importance of designing a blast plan. The aim of our work is to study the influence of one of the controllable parameters (spacing between blastholes) on the results of blasting as a function of the parameters used in the quarry (Ain kebira cement limestone quarry, Setif - Algeria) in order to identify the most influential ones. This done by simulating blasting plans using the digital software Wip Frag and the Kuz-Ram model, in which we changed the spacing between the holes, in order to evaluate and monitor the size distribution of the blocks in the blasted piles. The results of analyses carried out using the Kuz-Ram method and image processing with Wip Frag software indicate that reducing the distance between blastholes ensured good rock fragmentation
Green Roof Systems in Civil Engineering and Urban Resilience
No full textThe paper explores the role of green roof systems in advancing sustainable urban development and enhancing civil engineering practices in the face of growing climate-related and environmental challenges. The primary objective is to provide a comprehensive overview of green roofs as multifunctional, nature-based solutions that address key urban issues such as storm water management, urban heat island mitigation, air quality improvement, and biodiversity support. Drawing on recent research, and technical guidelines, the paper examines the structural engineering requirements, environmental performance metrics, regulatory frameworks, and urban planning strategies related to green roofs. It highlights both the benefits and limitations of current systems, including structural load constraints, maintenance challenges, and different local policies. The findings emphasize that successful implementation of green roofs depends on interdisciplinary collaboration, standardization of performance criteria, and supportive economic and regulatory instruments. Ultimately, the paper concludes that green roof systems represent a critical component of climate-resilient urban infrastructure and should be mainstreamed into civil engineering design, public policy, and sustainability agendas to meet the complex demands of future cities
Social Justice, Senior Mobility, and Sustainable Development in the Transportation Sector
No full textIn light of the United Nations Sustainable Development Goals (SDGs) and the world's aging population, achieving sustainable mobility for older individuals has emerged as a top policy goal. Even while inclusive mobility is a key component of many national and regional initiatives, there is still a continuous disconnect between these lofty goals and the practical capacity to measure and carry them out. By putting out a scientific framework for assessing the sustainability and equality of transportation systems for senior citizens, this research fills this gap. The paradigm, which is based on social justice and economic rationality, uses specific metrics to evaluate the spatial distribution of mobility resources, service accessibility, and infrastructural adequacy. The study illustrates how inclusive transport plans can increase accessibility, lower dependency costs, and promote active aging by drawing on European experiences, such as integrated mobility services in Nordic nations and accessibility-enhancing initiatives in the Netherlands and Germany. The suggested paradigm gives policymakers an evidence-based instrument for coordinating transportation investments with the SDGs' pledge to "leave no one behind" and facilitates rigorous comparisons across regional contexts. This strategy achieves the goal of sustainable development through transportation policy by combining the social, spatial, and economic aspects of mobility fairnes
A localized cutaneous scleroderma in woman after diatomaceous dust oral consumption: a case report
No full textBackground: Scleroderma-like disorders are heterogenous diseases characterized by sclerosis of the dermis, subcutis and sometimes the underlying soft tissues and bones. The clinical course of diseases may range from a benign local disease to a widespread systemic, life-threatening disease. There is a high risk of developing a systemic disease indistinguishable from idiopathic scleroderma in miners in coal and gold mines exposed to silica dust (silicon dioxide SiO2). Several cases of scleroderma morphea (circumscripta), a localized form with limited areas of skin sclerosis without Raynaud’s phenomenon or visceral involvement, have described in response to inhalatory exposure to silica dust. A 52-year-old woman was admitted to Rheumatology Clinic for clinical investigation of skin thickening on the abdomen, chest, and proximal thighs, along with pain, redness, and mild itching, a few months after taking fossil shell dust for six months, purchased from a pharmacy in Sofia. The instructions for use state that the product is a natural mineral – not a food, medicine, or dietary supplement that can be used as an additive in animal feed (for birds and mammals) with an anti-adhesive effect, and that it has a number of applications in the food industry. The patient took a level tablespoon of the contents of the package, dissolved in a glass of water, once a day – approximately 10 g of dust. The clinical skin findings consisted of violaceous erythema-infiltrative plaques. The histological diagnosis after skin biopsy of a lesion was scleroderma circumscripta. The chemical analysis of the skin sample showed a silicon content about ten times more than normal
Six new species of the genus Nitela Latreille (Hymenoptera, Crabronidae) from China, with a key to the Oriental species
No full textThis paper presents a systematic study on the Chinese species of the genus Nitela. Six new species from Yunnan, Hainan, and Guangdong Provinces are described: Nitela carinifrons, Nitela noncrenulata, Nitela punctidorsalis, Nitela transcarinata, Nitela tumidiscuta, and Nitela vecarinata. Diagnostic characters distinguishing these species from their congeners are provided. Additionally, three species are newly recorded from China: Nitela rugosa Williams, 1928, Nitela williamsi Menke, 1968 and Nitela domestica (Williams, 1928). A key to the Oriental species of the genus Nitela is provided
The role of laser technology in modern endodontics: a literature review
No full textIntroduction: Primary endodontic treatment and retreatment involves a number of stages and materials which are all crucial for the final result. Irrigation and the reduction of the microbial count in the root canal system represent a critical phase of the treatment process, contributing significantly to the overall success of the procedure. It was found that conventional methods and irrigants do not show satisfactory results. For this reason, different lasers are entering endodontics to combine with traditionally accepted materials. Aim: This literature review aims to examine the various aspects of laser applications in endodontics and their clinical significance. Materials and methods: In this literature review, related articles and publications are reviewed and research findings on the topic are summarized. Results: Review of all included articles and publications indicates that most types of lasers can be used in the course of endodontic treatment. Lasers are also used to remove pins, fractured instruments and old root canal filling. Conclusion: In this review, we have provided an overview of the emerging applications of lasers in endodontics and various common dental procedures, highlighting laser-based therapy as a promising approach in dental treatment
Green synthesis of copper nanoparticles using Daucus carota leaf extract and their anticancer activity against Hep3B liver cancer cells
No full textBackground: Hepatocellular carcinoma is among the most prevalent forms of cancer globally, and its treatment is often hindered by drug resistance and systemic toxicity. Recent advances in nanomedicine have enabled the development of metal-based nanoparticles with improved targeting efficiency and reduced side effects. In this context, green synthesis using medicinal plants presents a sustainable and biocompatible alternative for nanoparticle fabrication. Methods: Copper nanoparticles (CuNPs) were synthesized using an aqueous extract derived from Daucus carota leaves through a phytochemical-assisted reduction method. A 4 mM copper nitrate solution was reacted with 10 mL of concentrated leaf extract under constant stirring at 60 °C for 4 hours. The resulting nanoparticles were characterized using UV–Vis spectroscopy, transmission electron microscopy (TEM), and Scanning Electron Microscope (Sem) powder X-ray diffraction (XRD), and FTIR analysis. Antiproliferative activity was assessed via MTT assay on Hep3B liver carcinoma cells across a concentration gradient (10–100 µg/mL). Results: The synthesized CuNPs exhibited an average particle diameter of 58.3 nm with an irregular-spherical morphology, as revealed by TEM. UV–Vis spectroscopy confirmed a strong surface plasmon resonance peak at 276 nm. XRD patterns suggested a polycrystalline structure, and FTIR spectra indicated the presence of phenolic and carboxylic groups from the plant extract on the nanoparticle surface. In vitro cytotoxicity studies demonstrated a dose-dependent inhibition of Hep3B cells, with an estimated IC₅₀ value of 62 µg/mL for CuNPs, compared to 7.8 µg/mL for the reference chemotherapeutic agent, 5-fluorouracil. Conclusion: Biologically synthesized copper nanoparticles using Daucus carota extract exhibit promising anticancer potential against hepatic tumor cells. The eco-friendly synthetic route and moderate cytotoxicity profile support further investigation into their application in targeted cancer therapy