Search Results (167)

Varied types of particulate matter (PM) persist in the environment and exert a harmful impact on public health. The aim of this review article is to explore the key role of membrane technology in the separation of PM from ambient air. Nanofibrous, microporous, Janus, photocatalytic and hollow fiber membranes have found significant utilization in the effective separation of PM. Recent advancements in membrane technology and their key properties such as antibacterial activity, flame retardancy, wettability, thermal stability and reusability have been underscored in this review article. Moreover, the principles of PM separation have been discussed in detail to understand the working pathway of a membrane air filter via physical, chemical or biological approaches. A brief comparison between the conventional air filters and membrane air filters is provided in terms of cost, separation principle and respective merits and demerits to understand the importance of membranes in the realm of PM separation. This study also highlighted the commercial status of PM air filters with respect to their cost and scalability. By focusing on the innovations in membrane filters, this review article has highlighted the futuristic approaches such as green fabrication techniques, highly efficient material incorporation, use of AI/ML, etc., to overcome the challenges associated with conventional air filters. Full article

The continuously growing amount of oily wastewater from industrial, domestic, and natural sources poses a major threat to water sustainability, and thus efficient oil–water separation techniques are of utmost relevance. Membrane separation has been a popular approach due to ease of handling, high performance, and versatility. Among all the membrane materials, polylactic acid (PLA) and its derivatives have been of interest as green materials because of their renewability, biocompatibility, and biodegradability. PLA possesses special merits, including low density, high permeability, and high thermal stability. Despite its advantages, PLA also has some demerits, such as brittleness, low tensile strength, and poor heat resistance. These limitations are addressed by PLA-based membranes that are generally reinforced using fillers, surface modification, and structure optimization methods. This review provides a comprehensive overview of recent developments of PLA and its derivatives for oil–water separation, with an emphasis on membrane design, fabrication methods, and porosity enhancement strategies. Some significant fabrication processes like Thermally Induced Phase Separation (TIPS), Nonsolvent-Induced Phase Separation (NIPS), and Freeze Solidification Phase Separation (FSPS) are elaborately addressed. In addition, the review emphasizes methods to improve porosity, mechanical strength, and fouling resistance while maintaining biodegradability. By reviewing recent progress and remaining challenges, this review outlines the future potential of PLA membranes and aims to inspire more research on green, efficient oil–water separation. Full article

As cybersecurity threats continue to escalate, assessing the security and credibility of critical network nodes, such as web servers, email servers, and URLs, becomes pivotal to ensure network integrity. This entails a comprehensive evaluation of the network nodes’ reputation, employing reputation scores as performance indices to instigate bespoke protective measures, thereby alleviating Internet-associated risks. This paper examines the progress in the realm of IP reputation evaluation, providing an exhaustive analysis of reputation assessment methodologies premised on statistical analysis, similarity detection, and machine learning. Further, it underlines their practical applications and effectiveness in bolstering network security. In a head-to-head comparison of the assorted methods, the paper underscores their merits and demerits relative to implementation specifics and performance. In conclusion, it outlines the evolving trends and challenges in network reputation evaluation, providing a scientific framework and valuable technical references for prompt detection and effective mitigation of latent security threats in the network milieu. Full article

The primary focus of this paper lies in addressing the inadequate anti-dynamic jamming capability of the link layer within high-frequency (HF) access networks. To this end, we propose the incorporation of asymmetric frequency-hopping (AFH) technology within the wireless communication segment of HF access networks. This innovation aims to supersede the existing fixed-frequency and frequency-hopping communication methodologies, ultimately enhancing the network’s resilience against dynamic jamming. Moreover, we undertake a modeling analysis to delve into the ramifications of asymmetric frequency-hopping communication in dynamic jamming environments. This modeling framework serves to elucidate the dynamics of user spectrum occupation and jamming occurrences. Our proposed methodology leverages a two-dimensional Markov queuing model, equipped with a single server, for the purpose of managing the spectrum allocation within HF access network subnets. Consequently, the base station gains the capability to dynamically manage and adjust the available spectrum in real time, thereby effectively mitigating mutual jamming among users and facilitating the seamless implementation of asymmetric frequency hopping in HF access networks. Lastly, we conduct a simulation analysis to evaluate the changes in anti-jamming performance indices within the HF access network. This analysis compares the merits and demerits of utilizing fixed-frequency, frequency-hopping, and asymmetric frequency-hopping communication techniques. Our findings conclusively demonstrate that the integration of asymmetric frequency-hopping technology can significantly reduce outage and mutual jamming rates within HF access network subnets, thereby substantially bolstering their anti-jamming prowess. Full article

Concerns about sustainable energy sources arise due to the non-renewable nature of petroleum. Escalating demand for fossil fuels and price inflation negatively impact the energy security and economy of a country. The generation and usage of biofuel could be suggested as a sustainable alternative to fossil fuels. Several studies have investigated the potential of using edible crops for biofuel production. However, the usage of algae as suitable feedstock is currently being promoted due to its ability to withstand adverse environmental conditions, capacity to generate more oil per area, and potential to mitigate energy crises and climate change with no detrimental impact on the environment and food supply. Furthermore, the biorefinery approach in algae-based biofuel production controls the economy of algal cultivation. Hence, this article critically reviews different cultivation systems of algae with critical parameters including harvesting methods, intended algae-based biofuels with relevant processing techniques, other applications of valorized algal biomass, merits and demerits, and limitations and challenges in algae-based biofuel production. Full article

Silicon stands out as an exceptionally viable anode material, distinguished by its substantial capacity, plentiful natural reserves, eco-friendliness, and favorable low working potential. Nonetheless, the material’s pronounced volume fluctuations readily induce particle fragmentation, detachment of active components, and repeated disruption of the solid electrolyte interphase (SEI) layer. These factors contribute to a shortened cycle life and rapid capacity fading, thus hindering its practical application. The carbon composite approach can efficiently counteract these issues by capitalizing on silicon’s high capacity and employing carbon as a cushioning agent to diminish volume swelling, thus enhancing the deployment of silicon-based anode materials. This paper offers an exhaustive examination of the lithiation processes involved in Si/C anodes and delves into the strategic utilization of diverse carbon materials, including graphite, graphene, graphdiyne, carbon nanotubes, carbon fibers, MXenes, pitch, heteroatom-doped polymers, biomass-derived carbon, carbon-containing gas-derived carbon, MOFs, and g-C₃N₄ to advance the application of silicon in lithium-ion battery (LIB) anodes. Overall, this paper concentrates on summarizing the current research status and technological advancement and juxtaposes the merits and demerits of various carbon sources in Si/C anodes, thus providing a comprehensive assessment and forward-looking perspective on their future development. Full article

The Kitchen God has always been regarded as the protector of Chinese families and one of the most common and far-reaching gods in Chinese folk beliefs. The emergence and development of the Kitchen God are inseparable from the material carrier of the stove. The Han Dynasty was a critical period for the development and integration of stoves and the Kitchen God belief. Based on archaeological discoveries of cultural relics, characters and images, as well as relevant historical documents and records, this paper focuses on the interactive and symbiotic relationship between the spiritual belief in the Kitchen God and the material culture of kitchen stoves and its influence during the Han Dynasty. The Han Dynasty combined stoves with high cooking benches, large stove chambers, multiple burners, and functional designs that incorporated images of the Kitchen God, making them both practical and spiritual. The Kitchen God’s identity and functions were transformed from ancestor to household god, from giving food to monitoring merits and demerits, along with the renewal of stoves. These developments laid the foundation for the Chinese people’s earnest hope for a prosperous life and a peaceful and harmonious family. Full article

The escalating demand for sustainable materials has been fueling the rapid proliferation of the biopolymer market. Biodegradable polymers within natural habitats predominantly undergo degradation mediated by microorganisms. These microorganisms secrete enzymes that cleave long-chain polymers into smaller fragments for metabolic assimilation. This review is centered around dissecting the degradation mechanisms of specific biodegradable polymers, namely PLA, starch-based polymers, and plant fiber-based polymers. Recent investigations have unveiled that PLA exhibits augmented biocompatibility when combined with HA, and its degradation is subject to the influence of enzymatic and abiotic determinants. In the case of starch-based polymers, chemical or physical modifications can modulate their degradation kinetics, as evidenced by Wang et al.’s superhydrophobic starch-based nanocomposite cryogel. For plant fiber-based polymers, the effects of temperature, humidity, and cellulose degradation on their properties, along with the implications of various treatments and additives, are probed, as exemplified by Liu et al.’s study on jute/SiO₂/PP composites. Specifically, with respect to PLA, the polymerization process and the role of catalysts such as SnCl₂ in governing the structure and biodegradability are expounded in detail. The degradation of PLA in SBF and its interaction with β-TCP particles constitute crucial aspects. For starch-based polymers, the enzymatic degradation catalyzed by amylase and glucosidase and the environmental impacts of temperature and humidity, in addition to the structural ramifications of amylose and amylopectin, are further elucidated. In plant fiber-based polymers, the biodegradation of cellulose and the effects of plasma treatment, electron beam irradiation, nanoparticles, and crosslinking agents on water resistance and stability are explicated with experimental substantiation. This manuscript also delineates technological accomplishments. PLA incorporated with HA demonstrates enhanced biocompatibility and finds utility in drug delivery systems. Starch-based polymers can be engineered for tailored degradation. Plant fiber-based polymers acquire water resistance and durability through specific treatments or the addition of nanoparticles, thereby widening their application spectrum. Synthetic and surface modification methodologies can be harnessed to optimize these materials. This paper also consolidates reaction conditions, research techniques, their merits, and demerits and delves into the biodegradation reaction mechanisms of these polymers. A comprehensive understanding of these degradation mechanisms is conducive to their application and progression in the context of sustainable development and environmental conservation. Full article

Soft matter electrolytes could solve the safety problem of widely used liquid electrolytes in Li-ion batteries which are burnable upon heating. Simultaneously, they could solve the problem of poor contact between electrodes and solid electrolytes. However, the ionic conductivity of soft matter electrolytes is relatively low when mechanical properties are relatively good. In the present review, mechanisms of ionic conduction in soft matter electrolytes are discussed in order to achieve higher ionic conductivity with sufficient mechanical properties where soft matter electrolytes are defined as polymer electrolytes and polymeric or inorganic gel electrolytes. They could also be defined by Young’s modulus from about ${10}^5$ Pa to ${10}^9$ Pa. Many soft matter electrolytes exhibit VFT (Vogel–Fulcher–Tammann) type temperature dependence of ionic conductivity. VFT behavior is explained by the free volume model or the configurational entropy model, which is discussed in detail. Mostly, the amorphous phase of polymer is a better ionic conductor compared to the crystalline phase. There are, however, some experimental and theoretical reports that the crystalline phase is a better ionic conductor. Some methods to increase the ionic conductivity of polymer electrolytes are discussed, such as cavitation under tensile deformation and the microporous structure of polymer electrolytes, which could be explained by the conduction mechanism of soft matter electrolytes. Full article

Plastic film mulching technology occupies a prominent position in China’s agricultural production and plays an important role in improving crop yields, which can increase farmers’ income and ensure national food security. As the current residual film recycling mechanism is incomplete, the accumulation of residual film in the soil has gradually increased, and the problem of residual film pollution has posed a serious threat to agricultural production and the natural environment. Ridge mulching cultivation is one of the main planting patterns for grain and oil crops, such as peanuts, potatoes, and maize, in China. In this paper, the planting patterns, mulching conditions, characteristics, and distribution of residual film of the typical ridge mulching crops, such as peanut and potato, were analyzed. The merits and demerits of various kinds of residual film recycling machines and the application status and operation quality of peanut and potato residual film recycling machines are summarized. Problems and suggestions for the mechanized recycling of residual film were raised. This study may provide ideas for the development of residual film mechanization recycling of ridge mulching crops. The aim of this study is to propose practical solutions by analyzing the current status and existing problems of mechanized residual film recovery in order to reduce residual film pollution, protect the environment, and achieve sustainable agricultural development. Full article

With the development of novel vaccine strategies, T-cell epitope-based vaccines have become promising prophylactic and therapeutic tools against infectious diseases that cannot be controlled via traditional vaccines. T-cell epitope-based vaccines leverage specific immunogenic peptides to elicit protective T-cell responses against infectious pathogens. Compared to traditional vaccines, they provide superior efficacy and safety, minimizing the risk of adverse side effects. In this review, we summarized and compared the prediction and identification methods of T-cell epitopes. By integrating bioinformatic prediction and experimental validation, efficient and precise screening of T-cell epitopes can be achieved. Importantly, we delved into the development approaches to diverse T-cell epitope-based vaccines, comparing their merits and demerits, as well as discussing the prevalent challenges and perspectives in their applications. This review offers fresh perspectives for the formulation of safe and efficacious epitope-based vaccines for the devastating diseases against which no vaccines are currently available. Full article

Background: Supply chain companies have merits and demerits regarding operational and economic transactional policies. The effectiveness of supply chain companies corresponds to a cumulative score on a multi-criteria and perspectives-based evaluation. In this paper, we analyse the performances and challenges of several celebrated e-commerce companies to perceive their overall impression of supply chain management. Method: A mathematical model is framed as a multi-criteria decision-making (MCDM) problem with challenges as criteria and companies as alternatives. The criteria importance through inter-criteria correlation (CRITIC) method is used in this paper to adjust weights representing the available data. The ranking of e-commerce companies is evaluated using multi-objective optimization by ratio analysis plus the full multiplicative form (MULTIMOORA) method. Results: This model investigates the most dependent criteria and sub-criteria for the adaptation challenges of supply chain companies (SCCs). Furthermore, the SCCs are prioritized based on various conflicting criteria. Conclusion: Various challenges of SCCs, like logistics constraints, disruptions in supply chains, issues with technology, ethical sourcing and inconsistency between the products’ availability and the pace of consumption, are considered and analysed. We amassed the difficulties as criteria and sub-criteria in a numerical process using the MCDM approach. Additionally, the sensitivity and comparative of several optimal phenomena are analysed based on distinctive combinations of challenges in the ranking arena. Full article

Exact state-of-charge estimation is necessary for every application related to energy storage systems to protect the battery from deep discharging and overcharging. This leads to an improvement in discharge efficiency and extends the battery lifecycle. Batteries are a main source of energy and are usually monitored by management systems to achieve optimal use and protection. Coming up with effective methods for battery management systems that can adequately estimate the state-of-charge of batteries has become a great challenge that has been studied in the literature for some time. Hence, this paper analyses the different energy storage technologies, highlighting their merits and demerits. The various estimation methods for state-of-charge are discussed, and their merits and demerits are compared, while possible applications are pointed out. Furthermore, factors affecting the battery state-of-charge and approaches to managing the same are discussed and analysed. The different modelling tools used to carry out simulations for energy storage experiments are analysed and discussed. Additionally, a quantitative comparison of different technical and economic modelling simulators for energy storage applications is presented. Previous research works have been found to lack accuracy under varying conditions and ageing effects; as such, integrating hybrid approaches for enhanced accuracy in state-of-charge estimations is advised. With regards to energy storage technologies, exploring alternative materials for improved energy density, safety and sustainability exists as a huge research gap. The development of effective battery management systems for optimisation and control is yet to be fully exploited. When it comes to state-of-the-art simulators, integrating multiscale models for comprehensive understanding is of utmost importance. Enhancing adaptability across diverse battery chemistries and rigorous validation with real-world data is essential. To sum up the paper, future research directions and a conclusion are given. Full article

Manganese dioxide (MnO₂) nanomaterials have shown excellent performance in catalytic degradation and other fields because of their low density and great specific surface area, as well as their tunable chemical characteristics. However, the methods used to synthesize MnO₂ nanomaterials greatly affect their structures and properties. Therefore, the present work systematically illustrates common synthetic routes and their advantages and disadvantages, as well as examining research progress relating to electrochemical applications. In contrast to previous reviews, this review summarizes approaches for preparing MnO₂ nanoparticles and describes their respective merits, demerits, and limitations. The aim is to help readers better select appropriate preparation methods for MnO₂ nanomaterials and translate research results into practical applications. Finally, we also point out that despite the significant progress that has been made in the development of MnO₂ nanomaterials for electrochemical applications, the related research remains in the early stages, and the focus of future research should be placed on the development of green synthesis methods, as well as the composition and modification of MnO₂ nanoparticles with other materials. Full article

Proton exchange membrane fuel cells are a prime choice for substitute electricity producers. Membrane electrode assembly (MEA), bipolar electrodes, and current collectors belong to only a limited number of primary parts of the proton exchange membrane fuel cell (PEMFC). Bipolar plates are among the most famous elements in the fuel cell; they are responsible for the electrochemical reaction, as well as the flow of gases from one bipolar plate to another. A bipolar plate is to be a good electro-conducting, non-corrosive, and a high mechanical strength product. The attainability of the specification is achieved by graphite and metallic materials, each one having its own merits and demerits that are discussed in this article. Likewise, making the second pass for the flow pattern is equally important for the cell to have good performance and efficiency. The emergence of innovative and new bipolar plate designs has caused the achievement of high performance of these plates. The present review article principally focuses on the experimental study of diverse flow fields in the design of PEMFC and on the influence of various geometrical properties on the general operation of fuel cells made of PEMFC, and also on the manufacturing procedure utilized for building contemporary fuel cells. Full article