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Recycled Cellulose Acetate/Cerium Vanadate Nanoparticles Composite Membranes with Tuned Ultraviolet and Blue Light Shielding Capabilities
No full textUltraviolet radiation poses health risks with both immediate and long-term consequences. It is linked to various skin conditions such as skin cancer, sunburn, and aging. Radiation can negatively impact medication efficacy. UV radiation alters the color, texture, and taste of food, potentially making it unsuitable for consumption. Therefore, UV-shielding materials see significant research focus for various applications. Herein, different concentrations of CeVO4 nanoparticles were embedded in recycled cellulose acetate (CA) matrix to fabricate UV-shielding nanocomposite membranes. The UVC, UVB, UVA, and blue light transmittance through those membranes has been investigated. The addition of CeVO4 nanoparticles to the CA membrane resulted in a slight decrease in contact angle, indicating increased surface roughness and effective encapsulation of the nanoparticles within the CA matrix. The contact angle ranging from 64.22° to 65° indicates moderate hydrophilicity and a tendency for hydrophobicity, facilitating a stable and uniform distribution of the nanoparticles within the CA matrix. This balanced distribution is crucial to ensure sustained effectiveness in shielding against UV rays across the entire membrane. The recycled CA membrane and membranes containing 0.2 and 0.3 wt % CeVO4 exhibited similar UVC blocking behavior. The blocking efficiency of UVB remained stable for all CeVO4-containing membranes except for the membrane containing 0.6 wt % CeVO4, which exhibited a slightly increased transmittance after irradiation. Moreover, increasing the concentration of CeVO4 in the CA matrix resulted in enhanced blue light blocking. Therefore, the 0.1 wt % CeVO4@CA membrane is recommended for shielding against UVC and UVB, while the 0.6 wt % CeVO4@CA membrane is suitable for UVA and blue light blocking. This study introduces an approach that utilizes recycled CA and flower-shaped CeVO4 nanoparticles to fabricate membranes with enhanced thermal stability, superior light-blocking capabilities, and excellent optical properties. The results provide valuable insights into the development of advanced light-blocking membranes, addressing the limitations observed in previous studies and opening up possibilities for various applications requiring effective light shielding
Revolutionizing Metal-organic Frameworks (MOFs) in Wastewater Treatment Applications
No full textNanotechnology revealed its unlimited success in many real-life applications. That\u27s why the incorporation of nanomaterials became vital for solving a lot of current problems. Metal Organic-frameworks (MOFs) are nanomaterials with outstanding advantages such as crystallinity, high surface area, various structures, and adsorption capacity. Furthermore, metal-Organic Frameworks have emerged as versatile and promising materials for various environmental applications, including wastewater treatment. These materials are stable in water which acquire them convenient properties for wastewater treatment applications, for instance adsorption, catalysis, separation and so on. Moreover, MOFs are characterized by their high surface area, tunable pore size, and exceptional adsorption capacity, have shown remarkable potential for the removal of contaminants in wastewater treatment systems. In this review, the variable roles of MOFs in wastewater treatment applications have been discussed and highlighted as well. Herein, we are additionally reviewing the state-of-the-art research trends on the applications of metal-organic framework materials in the removal of pollutants in wastewater treatmen t systems
Unveiling the Main Frames of Islamophobia: Insights from Spanish Experts through Delphi Research
No full textSince the Gaza war began on October 7th, there has been a surge in anti-Arab and anti-Muslim bias worldwide. This paper explores the complex social issue of Islamophobia from a framing perspective, and proposes a new methodological approach based on a Delphi research with Spanish experts in the field to better understand the complexities of anti-Muslim rejection. Among two rounds, experts reached a consensus on certain conceptual issues but noted differences in Islamophobia targeting. They recognized the influence of religion, sexual orientation, sex, skin color, and ethnicity in shaping anti-Muslim speech. The study also highlighted challenges in distinguishing between conflicting scenarios like gender versus race-ethnicity, illegality versus crime, and invasion versus terrorism. Overall, this research sheds light on the nuances of Islamophobia as a multidimensional concept. Additionally, it aims to offer timely framework to improve journalistic treatment of this phenomenon, based on experts’ opinions
Indoor Air Quality and Ventilation Energy in University Classrooms: Simplified Model to Predict Trade-Offs and Synergies
Get PDFStudents and educators spend significant time in learning spaces on university campuses. Energy efficiency has become a concern among facility managers, given the need to maintain acceptable indoor air quality (IAQ) levels during and after the COVID-19 pandemic. This paper investigates the relationship between control and extraneous variables in a university classroom’s total mechanical ventilation (kWh). The model is built using Grasshopper software on Rhino Version 7. Our methodology encompasses (1) an extensive review of recent trends for studying IAQ and energy, (2) selecting parameters for simulation, (3) model configuration on Grasshopper, and finally, (4) a formulation of a pertinent equation to consolidate the relationship between the studied factors and the total mechanical ventilation energy (kWh). Central to this study are two key research questions: (1) What correlations exist between various parameters related to occupancy and IAQ in educational spaces? And (2) how can we optimize energy efficiency in university classrooms? The main contribution of this research is a generated equation representing the annual mechanical ventilation energy consumption based on selected parameters of classroom height, area, occupancy, window location, and ventilation rate of HVAC systems. We find that occupancy and class volume are the two most influential factors directly affecting mechanical ventilation energy consumption. The equation serves as a valuable estimation tool for facility managers, designers, and campus operations to investigate how fluctuations in occupancy can influence ventilation energy consumption in the physical attributes of a university classroom. This enables proactive decision-making, optimizing energy efficiency and resource allocation in real-time to promote sustainable and cost-effective campus operations
Design and Evaluation Support System for Convolutional Neural Network, Support Vector Machine and Convolutional Autoencoder
No full textRecently, deep learning approaches such as Convolutional Neural Network (CNN), Support Vector Machine (SVM), convolutional autoencoders (CAE) are widely applied to solve various kinds of industrial defect detection problems. Since 2017, the authors have developed a design, training, and evaluation support software available on MATLAB® for CNN, SVM, CAE, etc. Figure 3.1 shows the main dialogue of the developed application. Original models designed through the application can be applied to various classification and anomaly detection problems. As for CNN, not only initial learning-based CNN (ILCNN) with an original series-type structure but also the transfer learning-based CNN (TLCNN) using the convolutional blocks of already trained large-scaled CNNs such as AlexNet, GoogLeNet, VGG16, VGG19 and so on can be designed. As for SVM, two types of models can be constructed
Introduction: Mediterranean Migration Studies – A Research Agenda for the Coming Years
No full textThis volume seeks to cover the overall Mediterranean regional dimension on migrations. The basic purpose is to provide a basis for future research synergies by showcasing a plurality of perspectives to and applications of Mediterranean Migrations. This provides a direct opportunity and a reflective invitation to think the Mediterranean as a category of analysis for migration studies, which involves both a regional approach to migration and as “scale thinking†of geo-political governance. This broad geographical scope, coupled with cross-cutting and inter-disciplinary contributions, as well as the key-fact that this volume seeks to integrate regional, national, and North-Eastern-South complementarities are the distinctive features of its focus. It links Mediterranean and Migration Studies by articulating three sub-regions (Southern Europe, Northern Africa and Middle East) or the so-called Southern and Eastern Mediterranean (SEM) countries in the EU parlance
Media, Public Opinion and Migration Policies in Euro-mediterranean Countries: The Case of France
No full textIrregular migration from the southern shore of the Mediterranean to the northern shore is on the rise since 2011. This chapter concerns itself with how the media and the public in Northern Mediterranean countries reacted to this movement and how such reaction is concurrent with the policy debate. Focusing on France as a case study of a Northern Mediterranean country, the chapter reviews media coverage, public opinion surveys as well as the parliamentary debates in France between 2013–2016 which signified the peak of the movement. The review indicates that the policy debate as well as the legislation adopted were concurrent with public opinion. The chapter also concludes that the media and public’s perception of immigrants from Southern Mediterranean countries is mostly negative. Such negative perception and the associated policy that restrict migratory movement reflect the asymmetrical power relations between the two shores of the Mediterranean and France’ collective memory of migration. The French public perception of irregular migration is directly linked to the failure of earlier immigration and integration policies. The chapter concludes by pinpointing to the importance of approaching migration in the Mediterranean from a historical perspective
A Tale of two Egypts
No full textThis Audio Feature examines the intersection of personal history and national struggle during the 2011 Egyptian Revolution, delving into its lessons through the lens of Abdallah Al Ashaal\u27s (my grandfather) presidential journey
Evaluation of Green Roof Technology in Developing Countries
No full textRapid urbanization coupled with the population rise increases CO2 emissions and upsurges air pollution, which is highly harmful to human health and the continuity of the main kind. In developing countries, cities have poor green infrastructure leading to exaggerating heat island heat and lacking social green areas within urban centers; for example, 0.3 m2 of green space per person was estimated in 2009 in Cairo, Egypt (Attia and Amer in Green roofs in Cairo: a holistic approach for healthy productive cities, 2009 [1]). Even the few existing parks are not within walking distance from all citizens. On the other hand, most residential buildings are flat-roofed unused, or used as storage areas. It has excellent potential for being used as a shared social space. This study evaluates the possibility of implementing green roof technology as a climate change adaptation solution in developing counties, taking Egypt as a case study. Its methodology is mainly based on a comprehensive literature review and statistical data evaluation. By reviewing the potential market size for the green roof technology within the construction ecosystem and the capabilities of its implementation within existing and future buildings, the research presents a comparative analysis between green roof types and Egyptian building conditions considering the building use, structure, and social and economic standards of its users. An estimated 183–246 million m2 of green roof area can be implemented in Egypt. Up to 462 thousand kg of carbon dioxide can be eliminated from the atmosphere annually, and a minimum of 5.2 million kW can be saved monthly
Deciphering the functional and structural complexity of the Solar Lake flat mat microbial benthic communities
No full textThe Solar Lake in Taba, Egypt, encompasses one of the few modern-day microbial mats’ systems metabolically analogous to Precambrian stromatolites. Solar Lake benthic communities and their adaptation to the Lake’s unique limnological cycle have not been described for over two decades. In this study, we revisit the flat mat and describe the summer’s shallow water versus exposed microbial community; the latter occurs in response to the seasonal partial receding of water. We employed metagenomic NovaSeq-6000 shotgun sequencing and 16S rRNA, mcrA, and dsrB quantitative PCR. A total of 292 medium-to-high-quality metagenome-assembled genomes (MAGs) were reconstructed. At the structural level, Candidatus Aenigmatarchaeota, Micrarchaeota, and Omnitrophota MAGs were exclusively detected in the shallow-water mats, whereas Halobacteria and Myxococcota MAGs were specific to the exposed microbial mat. Functionally, genes involved in reactive oxygen species (ROS) detoxification and osmotic pressure were more abundant in the exposed than in the shallow-water microbial mats, whereas genes involved in sulfate reduction/oxidation and nitrogen fixation were ubiquitously detected. Genes involved in the utilization of methylated amines for methane production were predominant when compared with genes associated with alternative methanogenesis pathways. Solar Lake methanogen MAGs belonged to Methanosarcinia, Bathyarchaeia, Candidatus Methanofastidiosales, and Archaeoglobales. The latter had the genetic capacity for anaerobic methane oxidation. Moreover, Coleofasciculus chthonoplastes, previously reported to dominate the winter shallow-water flat mat, had a substantial presence in the summer. These findings reveal the taxonomic and biochemical microbial zonation of the exposed and shallow-water Solar Lake flat mat benthic community and their capacity to ecologically adapt to the summer water recession