Found 369 results
Open Access
Article
28 November 2025Sustainable Bioplastic Using Lignin Extracted from Neolamarckia cadamba Bark by Deep Eutectic Solvent
Lignin, a highly complex and abundant biopolymer, forms an integral part of plant cell walls and represents a promising resource for sustainable industrial applications. Lignin has recently gained attention due to its potential use in biofuels, bioplastics, adhesives, and antioxidant formulations. This paper focuses on lignin extraction from Neolamarckia cadamba bark by deep eutectic solvent (DES) composed of thymol and menthol. Extracted lignin and starch (extracted from Colocasia esculenta roots) were used for the synthesis of bioplastic. The extracted lignin was characterized through multiple analytical techniques, including UV-V is spectroscopy, FTIR, and visual staining with safranin. Bioplastic was characterized for thermal resistance, absorbance, and solubility. The moisture content was obtained as 29.59%, water solubility as 72.61% with almost completely (98%) biodegradable. The work contributes to valorising environmental biomass and enhancing the industrial relevance of lignin. Furthermore, it aligns with the sustainable development goals by transforming bio-waste into valuable bioproducts, such as bioplastics, biochemicals, bioadsorbents, etc. The outcomes of this research may serve as a foundation for future studies in lignin-based material innovation and biorefinery integration.
Open Access
Article
28 November 2025Binocular Camera-Based Depth Recognition for Motion Monitoring and Response Analysis of Flexible Floating Structures for Offshore Photovoltaics
Driven by the global goal of carbon neutrality, offshore floating photovoltaic (OFPV) technology has become a primary focus of photovoltaic research. In particular, flexible thin-film structures have become a central focus of research in sustainable energy development. It offers numerous advantages, including light weight, low cost, and strong adaptability to the marine environment. However, traditional experimental methods still face challenges in accurately capturing the motion response of flexible thin films. To address this issue, this study proposes a motion measurement and monitoring framework based on binocular vision. The framework is validated using gyroscope data, and the results demonstrate its high accuracy and real-time performance. The research team conducted experiments on a flexible floating photovoltaic structure in a wave flume, applying the proposed framework to monitor its motion response under wave excitation. The experimental results show that wave height and wave period have significant effects on the acceleration response of the thin film: higher wave heights lead to notably greater accelerations, whereas longer wave periods result in a gradual decrease in acceleration. Overall, the proposed framework provides reliable technical support for the design optimization and safety assessment of flexible thin-film FPV structures.
Open Access
Article
25 November 2025Dissimilar Joining of 316L and A131 Steel by Shield Metal Arc and Tungsten Inert Gas Welding to Evaluate Bending and Tensile Behavior
In this paper, the effect of filler metal and type of welding on the strength and ductility of dissimilar welding of two different grades of stainless steel was investigated. One of the benefits of stainless steel is its corrosion resistance, which is often necessary for equipment longevity in these facilities. During shipbuilding, as required, stainless steel 316L needs to be welded to the shipbuilding-grade carbon steel A131. In these applications, welding between the two should demonstrate superior strength during vessel construction. To provide a clear illustration, experimental work was needed to allow a careful selection of the joining procedure and filler metal or electrode. The current research work includes a comparative experimental analysis of dissimilar-metal welding (SS-316L & A131 steel). The reasons for choosing these two materials are their greater corrosion resistance and high strength in humid environments. Furthermore, two different welding methods (SMAW & TIG) with varying filler metals were employed in the experiment. The ultimate tensile strength and yield strength of the SMAW welds using E308-16 filler metal were the highest among all, while the TIG welds with ER308L showed superior bending strength. Observations suggest that SMAW with the E308-16 electrode exhibits superior tensile strength, while TIG joints with ER 308L filler provide better bending strength for the welding of SS-316L and shipbuilding (SB) grade A131 steels.
Open Access
Article
25 November 2025Ambient Air Pollution Exposure Influences Dementia through the Bidirectional Pathways of Psychological Factors and Brain Structure
Exposure to air pollution contributes to increased dementia risk, which may be mediated through its impact on psychological and brain structural changes. However, the underlying mechanisms remain poorly understood. We analyzed data from the UK Biobank of 263,095 participants aged 40 years and older. We examined the association between air pollution and incident dementia using Cox proportional hazard regression models. Mediation analysis was performed to explore the mediating roles of psychological and brain structural factors on these associations. Structural equation model (SEM) and bidirectional Mendelian randomization (MR) analyses were further employed to explore the potential pathways involving psychological factors and brain structure in this relationship. During an over 13-year follow-up, a total of 3039 dementia cases were identified. We observed significant associations between air pollution and dementia, with each interquartile range (IQR) increase in air pollution associated with a 5~9% increased risk of dementia. We observed that both psychological and brain structural factors mediated the air pollution-dementia association, particularly loneliness, social isolation, lack of enthusiasm, and reductions in volumes of the amygdala, hippocampus, temporal pole, and frontal pole, with mediation proportions ranging from 4.23% to 11.11%. SEM and MR analyses revealed bidirectional pathways linking air pollution exposure to dementia through psychological factors and brain structural changes: (1) air pollution → psychological disturbances → brain structural damage → dementia; (2) air pollution → brain structural damage → psychiatric disorders → dementia. These findings elucidate the interplay between psychological well-being and neuroanatomical integrity in mediating the neurocognitive impacts of air pollution, offering insights for targeted interventions to mitigate dementia risk associated with environmental exposures.
Open Access
Article
25 November 2025The Impact of Digital Infrastructure on Economic Resilience: Evidence from the Four Major Regions of China
Amid accelerating global structural changes and China’s transition to the digital-driven fourth industrial revolution, this paper examines the impact of digital infrastructure on economic resilience by clustering China’s 31 provinces into the four major economic regions during 2008–2022. Through the application of the Threshold Regression Model, Mediation Effect Model, and GTWR Model, the analysis reveals that digital infrastructure exhibits a threshold effect in enhancing economic resilience, with significant increasing marginal returns beyond specific scale thresholds. Regional heterogeneity is pronounced: the eastern region demonstrates amplified nonlinear benefits, while the northeast exhibits diminishing returns after crossing the threshold. Industrial diversification is an effective way for digital infrastructure to build resilience. The effects of industrial specialization, however, vary by region: it strengthens resilience in the east, weakens it in the central region, and shows no statistically significant impact in the western and northeastern regions. The findings provide empirical evidence for regionalized policymaking during technological paradigm shifts, highlighting the need to consider both digital infrastructure scale thresholds and industrial structure dynamics in economic resilience strategies.
Open Access
Article
18 November 2025Effects of Changing the Specific Surface Area in the Ceramic Matrix of CAC-Containing Refractory Castables on the Rheology and Processing
Besides the coarse and medium grain size distribution, the matrix components play a central role in the performance of refractory castables. Practical experience shows that the particle size distribution (PSD) and the specific surface area (SSA) of the ceramic matrix significantly influence processing, setting, and sintering behaviour. However, there is a lack of systematic studies on how changes in PSD or SSA affect castable properties. This study aims to address this gap by varying ceramic matrices to create model refractory castables with different matrix surface areas. Three dispersing agents with different mechanisms (electrosteric and steric) were used at graded concentrations. Results show that the SSA of the ceramic matrix has a significant influence on the rheological behaviour of refractory castables. A low SSA leads to shear thickening behaviour, a (very) low relative yield stress, and a high slump‑flow. Castables with an intermediate SSA and a multimodal composition show Bingham behaviour with a moderate relative yield stress and low relative viscosity, whereas a high SSA leads to shear thinning behaviour with a (very) high relative yield stress, (very) high relative viscosity, and a low slump-flow. Measurements of the dynamic viscosity of matrix suspensions at very low shear rates correlate with the rheological behaviour of fully composed refractory castables. Regression analysis using the Herschel‑Bulkley model successfully captures the observed qualitative relationships.
Open Access
Review
17 November 2025Enzyme-Mediated Carbon Dioxide Fixation: Catalytic Mechanisms and Computational Insights
Carbon conversion technologies that transform carbon dioxide (CO2) into high-value chemicals are pivotal for achieving sustainability. Among these, enzyme-mediated CO2 fixation has recently gained increasing attention as a more sustainable and environmentally friendly alternative to traditional chemical methods, which typically require harsh conditions and impose significant environmental costs. Recent advances in computer-aided techniques have greatly facilitated the mechanistic understanding of CO2-fixing enzymes and accelerated the development of enzyme-catalyzed carboxylation strategies. This review highlights recent progress in enzyme-mediated CO2 fixation by categorizing key enzymes into four classes based on their cofactor or metal ion requirements: cofactor-independent enzymes, metal-dependent enzymes, nicotinamide adenine dinucleotide phosphate (NAD(P)H)-dependent enzymes, and prenylated flavin mononucleotide (prFMN)-dependent enzymes. We outline the basic principles and applications of molecular dynamics (MD) simulations and quantum mechanical (QM) calculations, which serve as essential tools for investigating enzyme conformational dynamics and reaction mechanisms. Through representative case studies, we demonstrate how computational analyses uncover catalytic features that enhance CO2 conversion efficiency. These insights underscore the critical role of computer-aided approaches in guiding the rational design and optimization of biocatalysts, thereby advancing the application of enzyme-based systems for CO2 fixation.
Open Access
Article
17 November 2025The Reconstruction of China’s Land-Based Marine Pollution Governance under the Concept of “Rights of Nature”
Under the concept of “Rights of Nature”, the governance of land-based marine pollution in China faces unprecedented opportunities and challenges. Traditional governance paradigms are predominantly anthropocentric, treating the ocean as a resource to be utilized. From this perspective, governance measures for the prevention and control of land-based marine pollution primarily rely on administrative management and end-of-pipe treatments. Within this context, “Rights of Nature” provide a new pathway for marine ecological protection. However, promoting a shift in land-based marine pollution governance from the traditional anthropocentric view to an eco-centrism under the “Rights of Nature” concept is by no means an instantaneous process, and it must proceed gradually and systematically. Currently, China’s institutional framework for preventing and controlling land-based marine pollution remains dominated by the anthropocentric paradigm. Furthermore, it encounters multiple difficulties across many key areas, including the legal system, law enforcement mechanisms, relief mechanisms, and public participation. Issues such as poor coordination within the legal framework, fragmented law enforcement, lagging legislation related to ecological restoration, and insufficient public participation significantly constrain the effectiveness of land-based marine pollution governance. Given the fundamental differences between anthropocentrism and “Rights of Nature”, directly introducing this concept would likely have a substantial impact on China’s existing legal framework. Therefore, at the current stage, China could first incorporate the proposition from the “Rights of Nature” concept that nature possesses “intrinsic value independent of human use or perception”. This involves weakening the perception of the ocean as a mere appendage to human activities, recognizing and respecting the unique value of the ocean as a living entity and ecosystem at a conceptual level, and gradually forming a set of nature-friendly governance paradigms for land-based marine pollution that respect the intrinsic value of nature. This approach can ultimately drive transformative practices in China’s land-based marine pollution governance.
Open Access
Article
12 November 2025Topological Optimization for Environmental Sustainability in Civil Engineering Structures Design
The increasing demand for sustainable and cost-efficient construction highlights the need to minimize material consumption in civil engineering structures without compromising safety or performance. This study investigates the optimization of steel purlin cross-sections in metal buildings as a means to enhance structural efficiency and environmental sustainability. Finite Element Analysis (FEA) and the Solid Isotropic Material with Penalization (SIMP) method were employed to identify optimal material distributions and evaluate the effects of varying cross-section geometries. Both rectangular and IPE purlin sections were analyzed under realistic loading conditions to compare stress, deformation, and weight performance before and after optimization. The results demonstrate that substantial reductions in material mass, up to approximately 25–30%, can be achieved while maintaining nearly identical stress and displacement responses. These findings confirm that structural optimization effectively reduces both construction costs and environmental impact. The study concludes by recommending the adoption of topology and cross-section optimization techniques in the design of steel structures, particularly in public projects, to promote resource efficiency and sustainable construction practices.
Open Access
Case Report
10 November 2025Non-Fallot Absent Pulmonary Valve Syndrome in Fetuses: Key Insights for Prenatal Diagnosis and Postnatal Care
Absent pulmonary valve syndrome (APVS) is a rare cardiac malformation that is almost always associated with a Fallot-type ventricular septal defect (VSD). More rarely, it can occur with an intact ventricular septum or muscular VSD. The limited number of observations reported in the medical literature affects the quality of prenatal counselling given to the families concerned. We report 3 new cases of APVS without Fallot-type VSD, with 1 case associated with a muscular VSD, and have carried out a review of the literature on this rare malformation. Two of the fetuses had hydrops fetalis and one of these two had intra-uterine death. A 16p13.11 microduplication transmitted by the father was found in one fetus whose post-natal evolution was favorable following surgical ligation of an aneurysmal ductus arteriosus. A newborn with hydrops fetalis had a favorable outcome after spontaneous closure of the ductus arteriosus on the third day of life. Unlike Fallot-type APVS, non-Fallot type APVS is characterized antenatally by the constant presence of a large ductus arteriosus, the absence of aneurysmal pulmonary branches, a high frequency of chromosomal anomalies, but the absence of 22q11 micro deletion. After birth, early closure of the ductus may be indicated in cases of significant heart failure.
