Field Of Environmental Engineering Research Articles

Electrospun Polyvinylidene Fluoride Membranes: Waterproofing and Acoustic Performance for Air and Acoustic Vents in Electronics.

Advancements in electronic devices demand materials capable of exceptional performance in various challenging environments. This study presents polyvinylidene fluoride (PVDF) nonwoven membranes with controlled porosity, created using an air-guided electrospinning method, followed by a calendaring process. These membranes exhibit a combination of water-repellent properties and sound transmission capabilities, making them ideal candidates for use in air and acoustic vents in electronic systems. A key feature of our membrane is the three-dimensional nanostructured pores, ranging from 0.20 to 0.76 μm, with a mean pore size of 0.51 μm, achieved through the formation of randomly arranged long nanofibers. By employing both experimental and theoretical methods, we achieved impressive performance metrics: air permeability of 0.86 cm3/cm2/s, water contact angles up to 139.3°, and breakthrough pressure as low as 0.27 MPa. Our PVDF nonwoven membranes maintain an optimal balance of stiffness, density, and air permeability, leading to exceptionally low sound transmission loss values ranging between -10 and -40 dBV/Pa, all while preserving their structural integrity. These findings contribute to the development of next-generation waterproof and acoustically permeable membranes, offering enhanced performance capabilities in demanding operational scenarios. This work advances the field of nanomaterials, environmental engineering, and acoustic technologies, with the potential to influence the design of future electronic devices.

Controllable synthesis of amidoximated self-propelled tubular micromotors for enhanced uranium recovery: non-invasive mixing and on-the-move capturing

Micro-/nanomotors that combine attributes of autonomous movement and adsorption performance are attractive for efficient pollutant treatment. However, micro/nanomotors design still suffers from challenges including complex manufacturing processes, specific instrument demands and low yields. Herein, we proposed amidoxime-functionalized polydopamine tubular micromotors (DNBMs-AO) and demonstrated their application for rapid selective adsorption of uranium from contaminated seawater. The whole fabrication procedure is simplified and straightforward by curcumin templating and in-situ reduction/graft method. The manganese dioxide (MnO2) catalyst and amidoxime groups are subsequently anchored on the outer and inner side of nanotube surface. Besides, the distribution and amount of modified MnO2 and amidoxime groups can be manipulated via directly changing the reduction time. DNBMs-AO are driven and propelled by microbubbles produced by MnO2-triggered catalytic decomposition of hydrogen peroxide, which can reach high velocity at 302.6 μm s−1. The static adsorption results indicate that the adsorption of U(VI) onto DNBMs-AO can be better described by Langmuir model with the maximum adsorption capacity of 313.9 mg/g. Moreover, the motion of DNBMs-AO can efficiently improve the U(VI) diffusion under low H2O2 concentration, and enhance the adsorption kinetics to approximately 2.5 times. DNBMs-AO also exhibits high selectivity towards U(VI) and excellent performance stability, endowing its potential application in environmental engineering field.

Unsteady magnetohydrodynamic bioconvection Casson fluid flow in presence of gyrotactic microorganisms over a vertically stretched sheet

The free convective, unsteady, two-dimensional (2D) magnetohydrodynamic (MHD) Darcy–Forchheimer Casson fluid flow via a vertical stretching sheet containing gyrotactic microorganisms was the novel aspect of this investigation. We rewrote the collection of partial differential equations (PDEs) as nonlinear ordinary differential equations (ODEs) by considering an appropriate similarity variable. We solved the overhaul of nonlinear ODEs using MATLAB’s bvp4c approach. This study rigorously investigates the significance of gyrotactic microorganisms for Casson fluid motility. Additionally, this work investigates the impact of various parameters, including magnetic parameters, thermophoresis, Brownian motion, and radiation parameters, on temperature, motile microorganisms, velocity, and concentration profiles. We use graphs to illustrate the outcomes of various fluid flow parameters. Numerical tables display the effects of different parameters on skin friction, Sherwood number, Nusselt number, and the quantity of motile microorganisms. The unsteady parameter causes a drop in the velocity, temperature, concentration, and the density profile of microorganisms. Additionally, the Casson parameter leads to a decrease in the flow profile, while simultaneously increasing the heat, concentration, and microorganism density profiles. The microorganism density profile decreases as the bioconvection Schmidt number, Peclet number, and motile microbe parameter increase. We deem the new results extremely satisfactory when compared to earlier research. The fields of environmental remediation, biomedical sciences, and engineering may find this examination useful.

Research-based learning as an innovative approach for teaching students of environmental engineering: a case study of the emerging field of microplastics in soil

We implemented research-based learning (RBL) as an alternative to traditional frontal classroom lectures and laboratory sessions to impart knowledge on the emerging topic of microplastics in soil to students. The RBL module aimed at studying how microplastics (MPs) affect soil processes. We designed low-cost, small-scale and simple experiments for master’s students in Environmental Engineering at the Hamburg University of Technology. Students reported a clear understanding of concepts underlined by their presentation of the results and enthusiasm towards future exploration for their master’s or doctoral projects evidenced by a number of students carrying out research projects in the same field after finishing the module. The experiments were consequently published as an online learning module with the Hamburg Open Online University, to make them accessible for other students. The recent push in the education sector to include innovative teaching and learning methodologies offers new opportunities for RBL that are practical and replicable learning experiences that foster students’ research and problem-solving skills in areas of chemical, soil physics and environmental engineering fields.

The Future of Environmental Engineering Technology: A Disruptive Innovation Perspective

Scientific and technological revolutions and industrial transformations have accelerated the rate of innovation in environmental engineering technologies. However, few researchers have evaluated the current status and future trends of technologies. This paper summarizes the current research status in eight major subfields of environmental engineering—water treatment, air pollution control, soil/solid waste management, environmental biotechnology, environmental engineering equipment, emerging contaminants, synergistic reduction of pollution and carbon emissions, and environmental risk and intelligent management—based on bibliometric analysis and future trends in greenization, low carbonization, and intelligentization. Disruptive technologies are further identified based on discontinuous transformation, and ten such technologies are proposed, covering general and specific fields, technical links, and value sources. Additionally, the background and key innovations in disruptive technologies are elucidated in detail. This study not only provides a scientific basis for strategic decision-making, planning, and implementation in the environmental engineering field but also offers methodological guidance for the research and determination of breakthrough technologies in other areas.

Non-Linear Phenomena in Voltage and Frequency Converters Supplying Non-Thermal Plasma Reactors

Atmospheric pressure cold plasmas have recently been the subject of intense research and applications for solving problems in the fields of energy, environmental engineering, and biomedicine. Non-thermal atmospheric pressure plasma sources, with dielectric barrier discharges, plasma jets, and arc discharges, are non-linear power loads. They require special power systems, which are usually designed separately for each type of plasma reactor, depending on the requirements of the plasma-chemical process, the power of the receiver, the type of process gas, the current, voltage and frequency requirements, and the efficiency of the power source. This paper presents non-linear phenomena accompanying plasma generation in the power supply plasma reactor system, such as harmonic generation, resonance, and ferroresonance of currents and voltages, and the switching of overvoltages and pulse generation. When properly applied, this can support the operation of the above-mentioned reactors by providing improved discharge ignition depending on the working gas, thus increasing the efficiency of the plasma process and improving the cooperation of the plasma-generation system with the power supply.

Preface

7th International Conference on Civil and Environmental Engineering for Sustainability 9 - 10 October 2023 Impiana KLCC Hotel, Kuala Lumpur Malaysia https://intl-conference.com/iconcees2023 Faculty of Civil Engineering and Built Environment Universiti Tun Hussein Onn Malaysia Introduction The 7th International Conference on Civil and Environmental Engineering for Sustainability (IConCEES 2023) was held on the 9th and 10th of October 2023 at Impiana KLCC Hotel, Kuala Lumpur. This conference was held for the seventh time since 2009. With the theme “Engineering A Better Future: Multidisciplinary Perspectives on Sustainable Development,” was set the stage for profound discussions, ground-breaking insights, and a shared vision for world’s future. This 7th IConCEES 2023 is an ideal platform to share current ideas and findings on topics related to civil and environmental engineering. The fields of civil and environmental engineering have long stood as pillars in the evolution of societies. But as the planet grapples with unprecedented challenges, from climate change to urban sprawl, it has become abundantly clear that engineering solutions must be broader, deeper, and more interdisciplinary than ever before. IConCEES2023 is not just a conference; it’s a testament to global commitment to sustainable development. “Engineering A Better Future” is more than a slogan. It embodies the collective responsibility and the pressing need for innovation. It reminds that the blueprints, designs, and structures are not just for the present but are footprints for the generations to come. This conference aims to encourage all prominent scientists and researchers as well as industrial players together in one place so that can share and exchange ideas, knowledge, and expertise, widen networking among each other, and promote new technology towards a sustainable future. The two days conference was transcend borders and bridge disciplines. The topics that merge the technical, ethical, practical and visionary. From sustainable urban planning to eco-friendly construction materials, water resource management to renewable energy integration; the conference was showcase the amalgamation of expertise from different spheres, all with a singular goal. Namely, a sustainable tomorrow. This conference was conducted physically and virtually with 53 and 46 participants present physically and virtually, respectively. We used a conventional presentation set, such as a laptop and LCD projector, during the physical presentation. For the virtual presentation, we used the Microsoft Teams platform. The hybrid conference was held due to travel restrictions from several countries. There were no technical difficulties, as the setup was reliable, and the internet connection was stable throughout the session. For each presentation, either physical or virtual, a maximum of ten (10) minutes and five (5) minutes were allocated for each presentation, and a Question and Answer (Q&A) session. The Q&A was conducted immediately after each presentation. List of Organizing Committee, International Scientific Committee, Advisory Board, Editorial Board, Keynote Speaker, Reviewers and Authors / Participants are available in this pdf.

Environmental Blindspots: Identification and Mitigation using Technologies, Education, and Policies

Objectives:“Environmental Blindspots” are newly defined as a type of social problem within the realm of various environmental pollution and climate issues, wherein they are pushed down in priority due to factors such as corporate profit, consumer preferences, and government regulations, consequently remaining unresolved. This ultimately leads citizens to experience a sense of guilt. Despite the significant influence they wield on the welfare of current and future generations, various environmental social issues characterized by environmental blindspots (such as micro-hazardous substances like microplastics and environmental hormones) fail to become major considerations in societal decision-making. Consequently, they are not actively discussed within the social community. This absence of social consensus on these issues reflects the current situation. As a result, citizens repeatedly make choices that do not prioritize environmental values due to a perception of powerlessness stemming from the absence of environmentally friendly options, the belief that the issue is too immense to tackle individually, and lack of knowledge about specific actions to take for environmental problem-solving, among other factors. In this process, they experience involuntary and deliberate emotions of guilt. Since environmental blindspots are issues collectively experienced by the societal community comprising citizens, businesses, and government, solutions must also be derived collectively through collective thinking. This review has endeavored to incorporate such efforts.Methods:In this review, to develop a more effective interdisciplinary research methodology for addressing the previously mentioned environmental social issues, ten interdisciplinary researchers from the Environmental Engineering and Social Sciences fields at the center for convergence research (SEBIS) collaborated, leveraging their respective expertise to document literature survey results. Firstly, they reported on the environmental behavior, toxicity, distribution, and regulatory status of micro-hazardous substances, namely (micro)plastics and volatile organic compounds, which are the research subjects of the Environmental Blindspot Research Center. Secondly, they compiled relevant treatment technologies. Subsequently, they described the socio-structural causes of environmental blindspots and various solutions to environmental social issues through social science methodologies.Results and Discussion:To address the environmental blindspots, a key environmental social issue, it is necessary to advance various environmental technologies alongside responsible production by businesses and the enhancement of citizen environmental awareness. It is crucial for the government to institutionalize policies in the public domain to achieve this. Understanding the structural roles of citizens, businesses, and government is essential. It requires ethical consumer awareness and active participation, public campaigns and education, as well as effective government environmental policies to incentivize environmental friendly technological innovations by companies.Conclusion:In this review, the issue of environmental blindspots as an environmental social issue is being addressed comprehensively for the first time. Through this, we aim to establish an effective communication and cooperation system among social entities to explore solutions to environmental blindspots, and to propagate this ability to address social issues to future academic generations.

Fuzzy Machine Learning Applications in Environmental Engineering: Does the Ability to Deal with Uncertainty Really Matter?

Statement of Problem: Environmental engineering confronts complex challenges characterized by significant uncertainties. Traditional modeling methods often fail to effectively address these uncertainties. As a promising direction, this study explores fuzzy machine learning (ML) as an underutilized alternative. Research Question: Although the potential of fuzzy logic is widely acknowledged, can its capabilities truly enhance environmental engineering applications? Purpose: This research aims to deepen the understanding of the role and significance of fuzzy logic in managing uncertainty within environmental engineering applications. The objective is to contribute to both theoretical insights and practical implementations in this domain. Method: This research performs a systematic review carried out in alignment with PRISMA guidelines, encompassing 27 earlier studies that compare fuzzy ML with other methods across a variety of applications within the field of environmental engineering. Results: The findings demonstrate how fuzzy-based models consistently outperform traditional methods in scenarios marked by uncertainty. The originality of this research lies in its systematic comparison and the identification of fuzzy logic’s transparent, interpretable nature as particularly suited for environmental engineering challenges. This approach provides a new perspective on integrating fuzzy logic into environmental engineering, emphasizing its capability to offer more adaptable and resilient solutions. Conclusions: The analysis reveals that fuzzy-based models significantly excel in managing uncertainty compared to other methods. However, the study advocates for a case-by-case evaluation rather than a blanket replacement of traditional methods with fuzzy models. This approach encourages optimal selection based on specific project needs. Practical Implications: Our findings offer actionable insights for researchers and engineers, highlighting the transparent and interpretable nature of fuzzy models, along with their superior ability to handle uncertainties. Such attributes position fuzzy logic as a promising alternative in environmental engineering applications. Moreover, policymakers can leverage the reliability of fuzzy logic in developing ML-aided sustainable policies, thereby enhancing decision-making processes in environmental management.

Enzyme initiated in situ gelation as an oxygen-tolerant, high adhesive, and versatile strategy for hydrogel coating preparation

Hydrogel coatings have great potential for applications in antifouling, biomedical, and electronic fields, but the lack of preparation strategies with mild gel-forming conditions, high adhesion, and versatility hinders their widespread use. Herein, a method called glucose oxidase (GOD)-initiated in situ gelation (GOD-IIG) is developed for preparing hydrogel coatings. The procedure includes immobilizing Fe[Gly]2 and GOD on the surface of the substrates by forming an intermediate layer using epoxy resin, and then immersing the pre-treated substrates into a monomer solution to initiate polymerization. In situ gelation on the surface of the substrates is triggered by free radicals generated through the redox reaction between ferrous glycine (Fe[Gly]2) and hydrogen peroxide (H2O2) produced by the GOD-catalyzed glucose oxidation process, which can be carried out in open-air environments. Using the GOD-IIG method, hydrogel coatings constructed from common low-adhesive polymers displayed an adhesive strength of up to 686 kPa and stable underwater adhesion for at least 7 days. Moreover, this method shows controllable hydrogel thickness and recyclable monomer solution for at least 25 times at room temperature. It is also applicable to a variety of hydrogel structures and substrates, such as plastic, metal, and glass, regardless of flatness or geometry. In order to demonstrate the applications of hydrogel coatings prepared by GOD-IIG method, the lubrication and antifouling abilities of the coatings were assessed, and the results indicated that the coatings had good hydration lubrication as well as oil and biofouling resistance. This method holds promise for advancing the preparation of hydrogel coatings and has potential applications in the fields of electrical, biological, and environmental engineering.

Impact of insulation on energy consumption and CO2 emissions in high-rise commercial buildings at various climate zones

Abstract This study investigates the impact of insulation on energy consumption and CO2 emissions in high-rise commercial buildings across various climate zones. Through a simulation-based approach using the Hourly Analysis Program (HAP), the effectiveness of insulation in reducing energy demand and carbon emissions are evaluated. The research includes multiple climatic regions of Afghanistan, including arid, semi-arid, and mountainous zones. Methodologically, detailed building characteristics, climatic data, and insulation materials are considered, with energy modeling techniques applied to assess the performance of insulation measures. Results indicate varying degrees of energy savings and CO2 emissions reduction associated with insulation across different climate zones, in cities such as Kabul, Herat, Mazar, and Kandahar. Furthermore, the study calculates CO2 emissions reduction resulting from insulation addition, emphasizing the importance of sustainable building practices in mitigating environmental impacts. By underscoring the scientific value of this research in addressing a pressing global challenge and providing actionable insights for building design and energy policy, this study contributes to the advancement of knowledge in the field of sustainable construction and environmental engineering.

Prediction of Submergence of Islands Due to Glacier Melting & Sea Level Rise using Deep Learning

Prediction of Submergence of Island Due to Glacier Melting & Sea Level Rise will have significant contribution in the field of Environmental Engineering. This research paper present comprehensive overview of development and implementation this project, which designed to predict the submergence of island especially Lakshadweep Islands which is union territory of India. Capitalizing technologies like LSTM for forecasting sea level rise over period of time and Linear Regression for forecasting glacier melting and python for model training. To enhance the user experience also making it easy to understand the prediction we integrated JavaScript via python ELL framework to show charts and outputs. This paper discusses about the technical innovations, methodology and result of the project. It also spotlights its potential to help people living in islands which are submerging to evacuate them before this threat. This project aims to develop system to migrate people living on island and saving thousands of lives. Key Words: Submergence, LSTM, JavaScript, EEL, Model Training, Linear Regression, User Interface

EVALUATION OF THE BIOSORPTION OF Mn²⁺ AND Zn²⁺ BY PASSION FRUIT PEEL: STUDY OF DOSAGE AND CONTACT TIME

Objective: The objective of this study is to investigate he effectiveness of Mn2+ and Zn2+ biosorption by passion fruit peel as a sustainable and economically viable alternative to the biosorption process. Method: The methodology adopted for this research comprises the characterization of the biomass and batch tests. Tests were carried out with different masses of biomass in standard solutions of the metals investigated. The biosorption capacity of the biomass and the removal efficiency were calculated based on the differences in concentration of the metal ions. Results and Discussion: The results obtained revealed that the biomass showed high efficiency (close to 100%) for both cations. The contact time of 30 minutes was sufficient to reach equilibrium in the biosorption capacity of the metals, indicating the speed and effectiveness of the process. Research Implications: The practical and theoretical implications of this research provide valuable information on the application of passion fruit peel as a biosorbent in the removal of potentially toxic metals from contaminated wastewater. These results may influence practices in the field of environmental remediation and environmental engineering, as well as in agro-industrial waste management. Originality/Value: This study contributes to the literature by highlighting the originality of using passion fruit peel in natura as a biosorbent, presenting an innovative and sustainable approach to the remediation of contaminated effluents. The high efficiency of ion removal with low biomass dosages and short contact times adds knowledge to the field of biosorption using agro-industrial waste.

Construction of cationic conjugated microporous polymers containing pyrene units through post-cationic modification for enhanced antibacterial performance

BackgroundThe development of effective antibacterial agents with minimal cytotoxicity to human cells is a subject of great interest. Conjugated microporous polymers (CMPs) are a rapidly expanding and significant class of porous organic polymers. They are distinguished by their robust microporous architecture and π-conjugated framework. The molecular-level control over the pore structure and chemical composition of CMPs allows for precise customization to fulfill particular requirements. MethodsWe synthesized a cationic conjugated microporous polymer named Pyr-T-DPM Me CMP. This was achieved through post-synthetic modification of a pyrene-T-linked conjugated microporous polymer, Pyr-T-DPM CMP, formed via the Sonogashira coupling reaction of ethynyl pyrene (Pyr-T) and 2,5-dibromopyrimidine (Pyrimidine-Br2). The comprehensive analysis involved various techniques, including Fourier transform infrared (FTIR) spectroscopy, N2 adsorption/desorption isotherm, 13C solid-state NMR, X-ray photoelectron spectroscopy (XPS), thermogravimetry, transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Significant findingsThe antimicrobial efficacy of the newly synthesized CMPs was tested against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria. Due to the formation of N-methylpyrimidinium salts after quaternization, the cationic Pyr-T-DPM Me CMP exhibited enhanced bactericidal effectiveness against S. aureus compared to Pyr-T-DPM CMP, which lacked a positive charge. The viability of bacteria decreased with increasing concentrations of Pyr-T-DPM Me CMP, reaching maximum antimicrobial effectiveness at a concentration of 5 mg mL−1. To assess their impact on cell compatibility, we evaluated the cytotoxic effects on L929 cell fibroblasts, revealing minimal cytotoxicity towards L929 cells. Inspired by the superior antibacterial characteristics and exceptionally low toxicity of Pyr-T-DPM Me CMP, the novel cationic CMP developed in this study holds potential for application as beneficial antibacterial agent in the fields of environmental engineering and healthcare.

Sustainable Urban Drainage Systems (2014-2023) by Using Bibliometric Analysis Method

Sustainable urban drainage systems (SUDS) are increasingly crucial for stormwater management. This bibliometric review analyses research trends on sustainable urban drainage systems over the past decade (2014- 2023) using data from Scopus. The analysis found 705 articles, 192 conference papers, 85 book chapters, and 64 reviews on sustainable urban drainage systems. Publication volume increased by 66% during the study period, indicating rising research interest. The most cited article (294 citations) was a 2019 review by Andrés-Doménech et al. on innovations in sustainable urban drainage systems. Analysis of author keywords revealed 8 clusters of research topics, with "sustainable urban drainage systems" being the dominant term with 889 keywords. Although general sustainable urban drainage system terms prevail, the use of keywords related to network visualization methods like VOS viewer is rapidly increasing. The United Kingdom published the most SUDS research (315 articles), followed by China (149), Spain (135), the United States (126), and Italy (107 articles). Research was concentrated in the environmental science and engineering fields. However, this bibliometric analysis provides insights into SUDS research trends, the most active countries and institutions, and emerging topic areas. The rapid increase in publications and use of network visualization techniques demonstrates SUDS' growing importance in urban stormwater management. The results can help inform future research directions, such as applying advanced data analytics to improve SUDS design and performance. Expanding bibliometric analyses with additional techniques like VOS viewer could further enhance understanding of this critical area of urban environmental research. Developing bibliometric methods and adding feature extraction algorithms when selecting features used to model data can increase the efficiency and accuracy of the data on sustainable urban drainage systems. The development of research data using Vos viewers images with this type of data processing research can also be maximized for research related to the sustainable urban drainage system.

Advanced Filtration Techniques in Environmental Engineering

Granular filters and membrane filters, two essential filtration methods in environmental engineering, are thoroughly examined in this study. These techniques greatly aid air pollution control problems and water and wastewater treatment. The first section of the study outlines the basic ideas that underpin each filtration technique. The mechanical particle trapping mechanisms of granular filters, their wide range of applications in water treatment, and design factors, including media kinds and layers, are all examined. On the other hand, membrane filters are closely scrutinised because of their size exclusion principles, variety of types (from microfiltration to ultrafiltration), and vital function in industrial waste treatment and desalination processes. The study goes into additional detail about the maintenance, clogging, and financial ramifications that different filtering techniques must deal with. A comparison analysis provides insights into each method's applicability for various environmental engineering applications by illuminating its efficacy, affordability, and application specificity. The study's conclusion considers the potential for growth and current and upcoming technical developments in the filtration industry. This study lays the groundwork for forthcoming advancements and uses in the field of environmental engineering while also highlighting the significance of these filtering methods in modern ecological engineering.

Green Synthesis and Characterization of Zinc Oxide Using Carica papaya Leaf Extract

AbstractEnvironmental methodologies are gaining recognition in this modern world. Environmental nanotechnology plays a major role in improving modern fields of environmental engineering and science. Metal oxide nanoparticles have exceptional properties due to their small size, including quantum confinement, surface‐to‐volume ratio, plasmon excitation, high biocompatibility, and surface modifiability. The biosynthesis of nanoparticles using fungi, bacteria, and plants through various biotechnological techniques is currently a new paradigm for environmental protection. Synthesis of nanoparticles through plant extract is good because it eliminates the dangers of toxic chemicals, it is environmentally friendly, simpler, and safer as the reaction time is reduced and it can also be increased in size for higher operation. The present study is based on the development of zinc oxide nanoparticles from papaya leaf extract where zinc nitrate is used as a precursor. The biosynthesized nanoparticles are characterized by X‐ray diffraction, Fourier transform infrared spectroscopy, electron microscopy, energy‐dispersive X‐ray analysis, UV‐visible spectroscopy, and dynamic light scattering analysis. The crystalline phase determination of the zinc oxide nanoparticles is analyzed by X‐ray diffraction and the formation of polycrystalline zinc oxide nanoparticles is confirmed. FT‐IR spectrum reveals the main functional groups and chemical information in zinc oxide nanostructures. Morphological analysis is performed using SEM at different magnification levels. EDAX analysis shows the purity of the composite samples. Optical characterization is performed using a UV–vis spectrophotometer. DLS analysis shows that the nanoparticles formed have a relatively well‐defined dimension.

Analysis of Vibration Responses Induced by Metro Operations Using a Probabilistic Method

The environmental vibrations of tunnels and soil caused by metro operations is one of the most important issues in the field of environmental geotechnical engineering. Recent studies in metro-induced vibrations have revealed significant uncertainties in the vibration responses of tunnels and the surrounding soil. A two-step method of obtaining train loads considering uncertainty was introduced. The first step was to obtain the train loads via an inverse model based on measurements, and the second step was to quantify the uncertainty of train loads based on complex principal component analysis. A portion of a tunnel of the Beijing metro was selected as the object of study, where the vertical accelerations on the rail and on the tunnel wall were measured under different train speeds of 35, 45 and 55 km/h. Inputting the train loads based on the measured rail accelerations into an axisymmetric numerical model, established using ANSYS, the vibration responses of the tunnel wall in a probabilistic framework were calculated and were compared with the measured results. By using an accuracy index that considers both calculation bias and uncertainty, the accuracy of the calculated vibration response was quantitatively evaluated. It can be concluded that the calculated vibration response can reflect the actual vibration level and uncertainty of the tunnel wall. The accuracies of the calculated results under different speeds were generally high while showing a slight difference in amplitude.

High electricity generation and exhaust gas treatment enhancement using a microbial fuel cell of biological cathode equipped with conductive packing materials

Biotrickling filters (BTFs) designed for the treatment of volatile organic compounds (VOCs) have attracted much attention in the field of environmental engineering. As one of the main pollutants in VOCs, xylene is an aromatic hydrocarbon that poses a threat to human health. In this study, a biotrickling filter-microbial fuel cell (BTF-MFC) system was constructed to treat p-xylene by using a BTF filled with conductive packing materials as the biocathode for microbial fuel cell (MFC). The BTF-MFC showed good p-xylene removal performance even at high inlet concentrations. The elimination capacity reached 27.67 g/m3h at a 400 s empty bed residence time, and the removal efficiency reached 98.31% at a 300 s empty bed residence time. The conductive packing materials added to the BTF-MFC effectively promoted bacterial colonization, which as a result promoted p-xylene degradation and increased power output. The output voltage reached 725 mV, with a power density of 3.50 W/m2. The abundance of the genera Hydrogenophaga, Flavihumibacter, Chryseobacterium, and Mycobacterium, which have an excellent degradation capacity for aromatic compounds, increased during BTF-MFC operation.

Preface: 3rd International Conference on Green Environmental Materials and Food Engineering (GEMFE 2023)

We gratefully acknowledge the presence of all participants on the 2023 3rd International Conference on Green Environmental Materials and Food Engineering (GEMFE 2023), which was successfully held during November 25-26, 2023 in Rome, Italy. GEMFE 2023 aimed to provide a platform for experts, scholars, engineers, technicians, and R&D personnel to share scientific research results and cutting-edge technologies, understand academic development trends, broaden research ideas, strengthen academic research, and promote cooperation in the industrialization of academic results.
 GEMFE 2023 will bring together innovative academics and industrial experts in the fields of environmental engineering, energy technology, green materials, chemical science, agricultural technology, and food engineering to a common forum. About 80 participants from academic, high-education institutes, and other organizations took part in the conference. The conference model was divided into two sessions, including oral presentations and keynote speeches. In the first part, some scholars, whose submissions were selected as the excellent papers, were given 10 minutes to perform their oral presentations one by one. Then in the second part, keynote speakers were each allocated 30-40 minutes to hold their speeches.
 I would like to express special gratitude to members of the conference committee and organizers of the conference. I would also like to thank the reviewers for their valuable time and advice which helped in improving the quality of the papers selected for presentation at the conference and for publication in the proceedings.
 GEMFE 2023 Conference Organizing Chair
 Rome, Italy