Search Results (119)

Reducing environmental impacts and energy consumption in construction is increasingly important, prompting the use of renewable, ecological, and cost-effective materials. This research investigates an ecological building material combining clay and ground reed fibers, offering a promising alternative to conventional resources. A composite made of 50% clay and 50% ground reed was developed to study the influence of fiber size after grinding, as reed is typically used in its unprocessed form. Initial analyses included a physico-chemical characterization of both clay and reed. Thermal performance was then evaluated under steady-state and transient conditions to assess heat storage, heat transfer, and the material’s thermal inertia. The results showed a thermal conductivity of 0.38 W/m·K and an estimated 50% energy savings compared to clay alone, demonstrating the composite’s enhanced insulation capacity. Mechanical tests revealed compressive strengths of 2.48 MPa and flexural strengths of 0.79 MPa, with no significant effect from fiber size. The composite is lighter and more insulating than traditional clay blocks, indicating potential for reduced heating demand and improved indoor comfort. This study confirms the feasibility of incorporating ground reed fibers into clay-based composites to produce more sustainable building materials, supporting the transition toward energy-efficient and environmentally responsible construction practices. Full article

The use of thermal insulation material in building envelopes is closely related to economic benefits, energy-savings, and carbon reduction of buildings. The construction forms of different components in building envelopes have an important influence on the optimization design of thermal insulation in building envelopes. In this study, an integrated optimization approach is proposed to search for the best solution of thermal insulation in external walls and the optimal combination scheme of different construction forms of envelope components in granaries. The integrated optimization approach consists of an orthogonal experimental design (OEDM) method-based determination module of an optimal combination scheme of different construction forms of components, an assessment model-based quantitative analysis module, and an integrated assessment indicator-based selection module of the best solution of external wall insulation. Firstly, the OEDM method is used to determine the optimal combination scheme of different construction forms of the foundation wall of an external wall, thermal insulation material, external window, roof, and floors in buildings. Secondly, integrated economic, energy, and carbon analysis models are developed to analyze comprehensive performance of external wall insulation. Finally, an integrated assessment indicator consisting of an energy balanced index, a carbon balanced index, and weight coefficients is presented to determine the best solution of external wall insulation. The applications of this optimization approach in different ecological grain storage zones in China demonstrated that the outdoor air temperature characteristics could affect the comprehensive performance of external wall insulation in granaries, significantly. The best solution of external wall insulation in granaries in Turpan city, Daqing city, Kaifeng city, Changsha city, Anshun city, and Danzhou city was expanded polystyrene insulation (EPS) with a layer thickness of 0.078 m, 0.048 m, 0.083 m, 0.089 m, 0.062 m, and 0.131 m, respectively. The greatest difference in the lowest entire construction cost and the lowest carbon emission of external wall insulation among different typical climate regions in China was 12.987 USD/m² and 6.3 kgCO2e/m², respectively. Full article

This review is focused on glass fibers and natural fibers, exploring their applications in vehicles and buildings and emphasizing their significance in promoting sustainability and enhancing performance across various industries. Glass fibers, or fiberglass, are lightweight, have high-strength (3000–4500 MPa) and a Young’s modulus range of 70–85 GPa, and are widely used in automotive, aerospace, construction, and marine applications due to their excellent mechanical properties, thermal conductivity of ~0.045 W/m·K, and resistance to fire and corrosion. On the other hand, natural fibers, derived from plants and animals, are increasingly recognized for their environmental benefits and potential in sustainable construction, offering advantages such as biodegradability, lower carbon footprints, and reduced energy consumption, with a sound absorption coefficient (SAC) range of 0.7–0.8 at frequencies above 2000 Hz and thermal conductivity range of 0.07–0.09 W/m·K. Notably, the integration of these materials in construction and automotive sectors reflects a growing trend towards sustainable practices, driven by the need to mitigate carbon emissions associated with traditional building materials and enhance fuel efficiency, as seen in hybrid composites achieving 44.9 dB acoustic insulation at 10,000 Hz and a thermal conductivity range of 0.05–0.06 W/m·K in applications such as the BMW i3 door panels. Natural fibers contribute to reducing reliance on fossil fuels, supporting a circular economy through the recycling of agricultural waste, while glass fibers are instrumental in creating lightweight composites for improved vehicle performance and structural integrity. However, both materials face distinct challenges. Glass fibers, while offering superior strength, are vulnerable to chemical degradation and can pose recycling difficulties due to the complex processes involved. On the other hand, natural fibers may experience moisture absorption, affecting their durability and mechanical properties, necessitating innovations to enhance their application in demanding environments. The ongoing research into optimizing the performance of both materials highlights their relevance in future sustainable engineering practices. In summary, this review underscores the growing importance of glass and natural fibers in addressing modern environmental challenges while also improving product performance. As industries increasingly prioritize sustainability, these materials are poised to play crucial roles in shaping the future of construction and transportation, driving innovations that align with ecological goals and consumer expectations. Full article

The development of innovative and environmentally sustainable construction materials is a strategic priority in the context of the ecological transition and circular economy. Geopolymers and alkali-activated materials, derived from industrial and construction waste rich in aluminosilicates, are gaining increasing attention as low-carbon alternatives to ordinary Portland cement (OPC), which remains one of the main contributors to anthropogenic CO₂ emissions and landfill-bound construction waste. This review provides a comprehensive analysis of geopolymer-based solutions for building and architectural applications, with a particular focus on modular multilayer panels. Key aspects, such as chemical formulation, mechanical and thermal performance, durability, technological compatibility, and architectural flexibility, are critically examined. The discussion integrates considerations of disassemblability, reusability, and end-of-life scenarios, adopting a life cycle perspective to assess the circular potential of geopolymer building systems. Advanced fabrication strategies, including 3D printing and fibre reinforcement, are evaluated for their contribution to performance enhancement and material customisation. In parallel, the use of parametric modelling and digital tools such as building information modelling (BIM) coupled with life cycle assessment (LCA) enables holistic performance monitoring and optimisation throughout the design and construction process. The review also explores the emerging application of artificial intelligence (AI) and machine learning for predictive mix design and material property forecasting, identifying key trends and limitations in current research. Representative quantitative indicators demonstrate the performance and environmental potential of geopolymer systems: compressive strengths typically range from 30 to 80 MPa, with thermal conductivity values as low as 0.08–0.18 W/m·K for insulating panels. Life cycle assessments report 40–60% reductions in CO₂ emissions compared with OPC-based systems, underscoring their contribution to climate-neutral construction. Although significant progress has been made, challenges remain in terms of long-term durability, standardisation, data availability, and regulatory acceptance. Future perspectives are outlined, emphasising the need for interdisciplinary collaboration, digital integration, and performance-based codes to support the full deployment of geopolymer technologies in sustainable building and architecture. Full article

This study offers a detailed environmental, energy, and economic evaluation of thermal modernisation options for an existing single-family home in southern Poland. A total of 24 variants, combining different heat sources (solid fuel, biomass, natural gas, and heat pumps) with various levels of building insulation, were analysed using energy performance certification methods. Results show that, from an energy perspective, the most advantageous scenarios are those utilising brine-to-water or air-to-water heat pumps supported by photovoltaic systems, reaching final energy demands as low as 43.5 kWh/m²year and primary energy demands of 41.1 kWh/m²year. Biomass boilers coupled with solar collectors delivered the highest renewable energy share (up to 99.2%); however, they resulted in less notable reductions in primary energy. Environmentally, all heat pump options removed local particulate emissions, with CO₂ reductions of up to 87.5% compared to the baseline; biomass systems attained 100% CO₂ reduction owing to renewable fuels. Economically, biomass boilers had the lowest unit energy production costs, while PV-assisted heat pumps faced the highest overall costs despite their superior environmental benefits. The findings highlight the trade-offs between ecological advantages, energy efficiency, and investment costs, offering a decision-making framework for the modernisation of sustainable residential heating systems. Full article

This systematic literature review explores recent advancements in polymer-based composite materials designed for thermal insulation in automotive applications, with a particular focus on sustainability, performance optimization, and scalability. The methodology follows PRISMA 2020 guidelines and includes a comprehensive bibliometric and thematic analysis of 229 peer-reviewed articles published over the past 15 years across major databases (Scopus, Web of Science, ScienceDirect, MDPI). The findings are structured around four central research questions addressing (1) the functional role of insulation in automotive systems; (2) criteria for selecting suitable polymer systems; (3) optimization strategies involving nanostructuring, self-healing, and additive manufacturing; and (4) future research directions involving smart polymers, bioinspired architectures, and AI-driven design. Results show that epoxy resins, polyurethane, silicones, and polymeric foams offer distinct advantages depending on the specific application, yet each presents trade-offs between thermal resistance, recyclability, processing complexity, and ecological impact. Comparative evaluation tables and bibliometric mapping (VOSviewer) reveal an emerging research trend toward hybrid systems that combine bio-based matrices with functional nanofillers. The study concludes that no single material system is universally optimal, but rather that tailored solutions integrating performance, sustainability, and cost-effectiveness are essential for next-generation automotive thermal insulation. Full article

In many developing African countries, milk safety is often managed through traditional methods such as fermentation or boiling over firewood. While these approaches reduce some microbial risks, they present critical limitations. Firewood dependency contributes to deforestation, depletion of agricultural residues, and loss of soil fertility, which, in turn, compromise environmental health and food security. Solar pasteurization provides a reliable and sustainable method for thermally inactivating pathogenic microorganisms in milk and other perishable foods at sub-boiling temperatures, preserving its nutritional quality. This study aimed to evaluate the thermal and microbial performance of a low-cost solar milk pasteurization system, hypothesized to effectively reduce microbial contaminants and retain milk quality under natural sunlight. The system was constructed using locally available materials and tailored to the climatic conditions of the Savanna ecological zone in West Africa. A flat-plate glass solar collector was integrated with a 0.15 cm thick stainless steel cylindrical milk vat, featuring a 2.2 cm hot water jacket and 0.5 cm thick aluminum foil insulation. The system was tested in Navrongo, Ghana, under ambient temperatures ranging from 30 °C to 43 °C. The pasteurizer successfully processed up to 8 L of milk per batch, achieving a maximum milk temperature of 74 °C by 14:00 GMT. Microbial analysis revealed a significant reduction in bacterial load, from 6.6 × 10⁶ CFU/mL to 1.0 × 10² CFU/mL, with complete elimination of coliforms. These results confirmed the device’s effectiveness in achieving safe pasteurization levels. The findings demonstrate that this locally built solar pasteurization system is a viable and cost-effective solution for improving milk safety in arid, electricity-limited regions. Its potential scalability also opens avenues for rural entrepreneurship in solar-powered food and water treatment technologies. Full article

The global climate crisis has shifted the building industry toward the ecological use of materials, often based on renewable sources. Properties of such materials, as well as their behavior in structures, need to be constantly verified both theoretically and experimentally. This article focuses on the influence of vapor retarder on the moisture content of timber log wall structures with sheep wool insulation. Moisture content was verified experimentally during the period of over 2 years with monitoring sensors and insulation samples weighing. Results show that vapor retarder has a positive and statistically significant impact on the moisture content of sheep wool insulation and log structure, depending on the season and position of insulation in the structure. The moisture content of the log structure does not exceed 16%, confirming no risk of biodegradation during the monitored period. This case study can help further the knowledge of log structure design and provide insight into the hygrothermal properties of sandwich structures. Full article

Petroleum-based insulating liquids have traditionally been used in the electrical industry for cooling and insulation. However, their environmental drawbacks, such as non-biodegradability and ecological risks, have led to increasing regulatory restrictions. As a sustainable alternative, vegetable-based insulating liquids have gained attention due to their biodegradability, non-toxicity to aquatic and terrestrial ecosystems, and lower carbon emissions. Adopting vegetable-based insulating liquids also aligns with United Nations Sustainable Development Goals (SDGs) 7 and 13, which focus on cleaner energy sources and reducing carbon emissions. Despite these benefits, most commercially available vegetable-based insulating liquids are derived from edible seed oils, raising concerns about food security and the environmental footprint of large-scale agricultural production, which contributes to greenhouse gas emissions. In recent years, waste cooking oils (WCOs) have emerged as a promising resource for industrial applications through waste-to-value conversion processes. However, their potential as transformer insulating liquids remains largely unexplored due to limited research and available data. This review explores the feasibility of utilizing waste cooking oils as green transformer insulating liquids. It examines the conversion and purification processes required to enhance their suitability for insulation applications, evaluates their dielectric and thermal performance, and assesses their potential implementation in transformers based on existing literature. The objective is to provide a comprehensive assessment of waste cooking oil as an alternative insulating liquid, highlight key challenges associated with its adoption, and outline future research directions to optimize its properties for high-voltage transformer applications. Full article

The pine wood nematode (Bursaphelenchus xylophilus, PWN) is a globally significant quarantine pest that causes severe economic and ecological damage to coniferous forests worldwide. Additionally, PWNs continue to expand into higher latitudes. However, studies on their cold tolerance remain limited. This study investigated the overwintering environment of PWNs in epidemic areas of Liaoning Province, China. It established a protocol to induce anhydrobiosis in PWNs, evaluated their low-temperature resistance, observed morphological changes during anhydrobiosis, and explored potentially involved key genes. The results showed that (1) there was no significant difference in thermal insulation between infected and healthy wood in Liaoning Province; both effectively reduced temperature fluctuation rates, providing a protective function for PWN overwintering. (2) PWNs significantly enabled their cold tolerance through anhydrobiosis, accompanied by significant morphological changes and substantial lipid droplet depletion. (3) Eleven anhydrobiosis-related genes were identified. Among these, the collagen gene family showed consistent expression patterns throughout dehydration and rehydration. This suggests a potential role in cuticle structural changes and osmoregulation during anhydrobiosis. These findings provide a theoretical basis for understanding how PWNs survive winter conditions in high-latitude regions. Additionally, they offer valuable insights for future research into PWN anhydrobiosis and the development of effective control strategies. Full article

As the core carrier of cognitive construction, the design optimization of campus learning space is crucial to the improvement of education quality, but the existing research focuses on the analysis of behavioral preferences and lacks an in-depth analysis of the psychological dynamics of users. Through multimodal questionnaires and spatiotemporal tracking, we developed an ‘expectation–perception–behavior’ framework to quantify discrepancies between users’ visual expectations and actual experiences. The results showed that blue and wood tones significantly enhanced learning efficiency; however, there was a significant difference between facility usability and sound insulation. Based on this, dynamic environment adjustment, virtual reality preview, and modular flexible space strategies are proposed to optimize spatial performance through biophilic design and intelligent regulation. This study provides interdisciplinary methodological innovation for architecture, education, and environmental psychology and promotes the transformation of campus space, injecting new momentum into the transformation of global stock space, the construction of a sustainable education ecology, and contributing to the overall improvement of social cognitive performance. Full article

Cold stress impacts lamb mortality, welfare, and productivity. Wool and skin insulate lambs, but the mechanisms underlying their response to colder environments remain unclear. Shorn lambs (n = 20) of similar age (8 months), of the Hulunbuir (n = 10; average 34.5 ± 0.70 kg) and Hu (n = 10; average 34.9 ± 0.79 kg) breeds, were raised at the Ecological and Agricultural Experimental Station, Gaolan, Gansu Province, People’s Republic of China (36°13″ N, 103°47″ E), at an altitude of 1780 m above sea level. These lambs were divided into four equal groups: Hulunbuir at −20 °C (HB−20), Hulunbuir at 15 °C (HB+15), Hu at −20 °C (HU−20), and Hu at 15 °C (HU+15). The groups were maintained at these temperatures in temperature-controlled facilities for 38 days. Skin tissues were analyzed with transcriptome sequencing, and selected wool and physiological traits were assessed. The HB−20 lambs had greater wool length growth (1.8 ± 0.13 vs. 1.0 ± 0.46 cm, p < 0.001) and epidermis thickness (20.0 ± 1.20 vs. 14.6 ± 0.87 μm, p = 0.006) but lower hair follicle density (33.6 ± 2.11 vs. 42.7 ± 3.06 per mm², p = 0.041), rectal temperature (38.1 ± 0.10 vs. 38.8 ± 0.04 °C, p < 0.001), and respiratory rate (15.5 ± 1.08 vs. 24.0 ± 1.89 breaths/min, p = 0.004), compared to the HB+15 lambs. Similar differences in these traits were observed with the Hu lambs at the two temperatures. Transcriptome analyses revealed the activation of pathways related to immune and endocrine systems, signal transduction, and development and regeneration, irrespective of breed at −20 °C. The TNF signaling pathway and osteoclast differentiation may play roles in cold adaptation, as they are associated with differentially expressed genes (DEGs) identified in the Hulunbuir lambs, as well as shared DEGs between both breeds. This study revealed physiological and molecular differences in lambs exposed to lower temperatures and suggests potential targets for improving cold tolerance, welfare, and productivity. Full article

Seagrass ecosystems provide essential ecological services and are increasingly recognized for their potential as sustainable building insulation. While prior studies have examined seagrass insulation in temperate climates, its suitability for tropical construction remains largely unexplored. This study assesses the insulation performance, practical challenges, and adoption barriers of seagrass insulation in tropical climates, using building physics simulations and structured expert interviews, with case studies in Seychelles and Auroville, India. Simulation results indicate that seagrass insulation with its high specific heat capacity effectively reduces overheating risks and demonstrates consistently low mould-growth potential under persistently humid tropical conditions. Despite these technical advantages, expert interviews reveal significant non-technical barriers, including negative public perception, regulatory uncertainties, and logistical complexities. Seychelles faces particular hurdles such as limited coastal storage capacity and stringent environmental regulations. In contrast, Auroville emerges as an ideal demonstration site due to its strong sustainability culture and openness to innovative building materials. The study further identifies that integrating seagrass insulation into a structured, regulated supply chain—from sustainable harvesting and processing to quality assurance—could simultaneously enhance ecosystem conservation and material availability. Implementing a harvesting framework analogous to sustainable forestry could ensure environmental protection alongside supply stability. The findings emphasize the urgent need for targeted awareness initiatives, regulatory alignment, and economic feasibility assessments to overcome barriers and enable wider adoption. Overall, this research highlights seagrass insulation as a promising, climate-positive construction material with strong potential under tropical conditions, provided that identified logistical, societal, and regulatory challenges are addressed through dedicated research, stakeholder collaboration, and practical pilot projects. Full article

The construction sector plays a key role in climate change due to its high energy consumption and greenhouse gas emissions. Developing environmentally friendly building materials with low environmental impact is essential to improving energy efficiency. Insulation derived from agricultural waste is particularly promising due to its low ecological footprint, responsible resources use, and potential for integration into various construction systems. This study evaluates the potential of rice husk fiber as a thermal insulating material applied through the blowing technique in the Skylark 250 modular system. Rice husk fiber was morphologically and thermally characterized using scanning electron microscopy (SEM), while its thermal behavior was analyzed by thermogravimetric analysis (TGA) alongside a fire behavior assessment. Additionally, energy simulations were conducted to compare the thermal performance of rice husk fiber with other insulating materials when integrated into a building’s thermal envelope. The results showed an average thermal conductivity of 0.040 W/mK, a U-value of 0.17 W/m²K, and a heating demand of 9.56 kWh/m²-year when applied to the modular system. The material also exhibited good fire resistance, with a smoldering velocity of 3.40 mm/min. These findings highlight rice husk fiber’s potential as a sustainable insulation material for modular construction, contributing to energy efficiency and climate change mitigation. Full article

Straw has been used as a building material since time immemorial and has been considered as a waste product from the agricultural sector, usually used for feed, bedding, or fertilization. Nowadays, the construction industry strives to reduce greenhouse gas emissions and is focusing on renewable materials; hence, straw seems to be an attractive, low-energy option. Straw bales or blown insulation are common uses, with limited detailed knowledge regarding the properties of different straw types. Straw is made up of the dry stems of crops. Straw’s chemical composition will differ with different crops and can have a great impact on its effectiveness. As a renewable material, straw also has the potential to be used in buildings, enhancing thermal insulation and reducing environmental impacts. This study considers four kinds of straw: barley, oats, oilseed rape, and triticale, regarding their possible usage in insulation materials. The thermal conductivity, bulk density, and dust generation of each type were tested in the laboratory. Among them, the best performance was shown by the barley straw treated with mechanical pulping using a knife mill at 4000 rpm for 60 s, which showed the lowest bulk density and thermal conductivity and generated the least dust. It is thus proven to be an environmental insulation material with significant implications for sustainable construction and energy-efficient building design, further helping in maintaining environmental sustainability in building construction. Full article