• Composites Research
• /
• v.33 no.6
• /
• pp.408-414
• /
• 2020

The present engineering sector focused on the sandwich composites and almost covered all engineering fields because of decent mechanical properties with a lightweight structure. It mainly consists of high strength fiber skin and porous structure core like corrugated, honeycomb, balsa wood, and foams which is playing a pivotal role in weight reduction. Recently researchers attention grabbed by Natural fiber sandwich composites due to biodegradability, renewable, low-cost, and environmentally friendly. However special focus is highly needed towards the flammability behavior of natural fibers used as reinforcement for composites. Herein, for the first time, the flame retardant natural fiber sandwich composite was fabricated by using flame retardant treated bamboo fabric and vinyl ester via the VARTM process. The impact of flame retardant treated bamboo fabric on mechanical and flame retardant properties were studied. The results concluded that the fabricated bamboo sandwich composites show structurally lightweight with significant mechanical strength and feasibility with respect to the flame.

• The Journal of the Convergence on Culture Technology
• /
• v.8 no.5
• /
• pp.553-559
• /
• 2022

The film mulching technology is useful for controlling soil temperature and moisture by covering the soil surface, and for suppressing weeds. In this study, in order to improve the hydrolysis resistance and mechanical properties of the biodegradable mulching film, PBAT(Poly butylene adipate-co-terephthalate) and PLA(Poly lactic acid) were modified using a twin-screw extruder and then the physical and biodegradable properties of the film were investigated. After landfill the mulching film in soil, the weight reduction of the film was confirmed by period, and plant growth was observed after mulching in the dry paddy field for rice farming. Mulching films with improved hydrolysis resistance showed excellent crop growth properties, and biodegradable mulching films can offer potential as a new alternative for environmentally friendly, efficient and sustainable agricultural practices.

• Geomechanics and Engineering
• /
• v.32 no.3
• /
• pp.347-359
• /
• 2023

With the development of infrastructure, there is a critical shortage of filling materials all over the word. However, a large amount of silt accumulated in the lower reaches of the Yellow River is treated as waste every year, which will cause environmental pollution and waste of resources. Microbial induced calcium carbonate precipitation (MICP) technology, with the advantage of efficient, economical and environmentally friendly protection, is selected to solidify the abandoned Yellow River silt with poor mechanical properties into high-quality filling material in this paper. Based on unconfined compressive strength (UCS) test, determination of calcium carbonate (CaCO₃) content and scanning electron microscope (SEM) test, the effects of cementation solution concentration, treatment times and relative density on the solidification effect were studied. The results show that the loose silt particles can be effectively solidified together into filling material with excellent mechanical properties through MICP technology. The concentration of cementation solution have a significant impact on the solidification effect, and the reasonable concentration of cementation solution is 1.5 mol/L. With the increase of treatment times, the pores in the soil are filled with CaCO₃, and the UCS of the specimens after 10 times of treatment can reach 2.5 MPa with a relatively high CaCO₃ content of 26%. With the improvement of treatment degree, the influence of relative density on the UCS increases gradually. Microscopic analysis revealed that after MICP reinforcement, CaCO₃ adhered to the surface of soil particles and cemented with each other to form a dense structure.

• Composites Research
• /
• v.36 no.2
• /
• pp.69-79
• /
• 2023

Oil-water separation is a critical process for several industrial applications, including oil production, wastewater treatment, food processing, and environmental area such as marine oil spills. The separation efficiency of oil-water mixtures can be influenced by various factors such as mixture composition, oil and water conditions, and the separation technology used. Over the years, various technologies have been developed to separate water and oil by physical, chemical and biological methods. This paper presents an overview of the various methods and technologies available for oil-water separation, including gravity separation, centrifugal separation, and separation using adsorbents, filters. The strengths and limitations of each method are discussed, along with recent research trends and future prospects. Furthermore, this paper aims to provide direction for future research and industrial application of sustainable and environmentally friendly oil-water separation technologies. In conclusion, we provide a comprehensive overview of recent oil-water separation technologies that will be beneficial to researchers and industrialists in the field of oil-water separation.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.11 no.4
• /
• pp.501-508
• /
• 2023

Addressing urban noise problems, this study develops eco-friendly, inorganic sound-absorbing panels, overcoming the limitations of traditional PMMA and cement-based panels. These conventional panels pose safety risks due to flammability and environmental concerns due to carbon emissions. Utilizing industrial waste, the research comprises two phases: initial tests for physical and performance characteristics (fluidity, density, compressive strength, sound absorption) and subsequent development of optimized panel mixtures. This approach aims to replace existing panels with sustainable, effective alternatives, significantly contributing to safer, environmentally responsible urban infrastructure. The findings of this study have implications for the sound panel market, offering novel solutions for noise control while aligning with environmental and safety standards.

• Journal of the Microelectronics and Packaging Society
• /
• v.30 no.4
• /
• pp.17-31
• /
• 2023

Amidst escalating global warming fueled by indiscriminate fossil fuel consumption, concerted efforts are underway worldwide to mitigate atmospheric carbon dioxide (CO₂) levels. Electrochemical CO₂ reduction technology is recognized as a promising and environmentally friendly approach to convert CO₂ into valuable hydrocarbon compounds, deemed essential for achieving carbon neutrality. Copper, among the various materials used as CO₂ reduction electrodes, is known as the sole metal capable of generating C₂₊ compounds. However, low conversion efficiency and selectivity have hindered its widespread commercialization. This review highlights diverse research endeavors to address these challenges. It explores various studies focused on utilizing copper-based electrodes for CO₂ reduction, offering insights into potential solutions for advancing this crucial technology.

• Food Science and Preservation
• /
• v.31 no.1
• /
• pp.1-14
• /
• 2024

The utilization of coatings composed of bio-based materials in the processing and preservation of meat presents an environmentally conscious, secure, cost-effective, and superior method for prolonging the storage life of meat while also preserving its nutritional value. In this study, changes in physical, chemical, and microbiological characteristics of freshly cut beef coated with distilled water (control) and keratin-starch composites (K-S) functionalized with 0.0-, 0.2-, 0.6-, and 1.0-mL avocado peel polyphenolic-rich extract (APPPE) kept at 4℃ for 12 days were evaluated periodically at 3-day interval using standard techniques. Keratin was extracted from waste feathers, while starch was obtained from ginger rhizomes. Following a 12-day storage period, beef coated with APPPE-enriched K-S composites exhibited a significant (p<0.05) improvement in shelf life by minimizing deteriorative changes in pH and color (as determined by metmyoglobin level) in addition to inhibiting oxidative changes in lipids (as determined by TBARS level) and proteins (protein carbonyl level) in comparison to control and K-S composite without APPPE. Furthermore, microbial growth was significantly (p<0.05) suppressed in meat coated with K-S composite functionalized with APE at 0.6 and 1.0 mL compared to the control. The study suggested that APPPE-enriched K-S composite could offer an eco-friendly and safe food preservation technique for fresh meat.

• Advances in materials Research
• /
• v.13 no.3
• /
• pp.211-220
• /
• 2024

Polylactic acid or polylactide (PLA) is a biodegradable thermoplastic that can be produced from renewable material to create various components for industrial purposes. In 3D printing technology, PLA is used due to its good mechanical, electrical, printing properties, environmentally friendly and non-toxic properties. However, the physical properties and excellent electrical insulation properties of PLA have limited its application. In this study, with the carbon black (CB) as filler added into PLA, the lattice spacing and morphology were investigated by using X-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. The physical properties of PLA-carbon composite were evaluated by using tensile test, shore D hardness test and density and voids measurement. Impedance test was conducted to investigate the electrical properties of PLA-Carbon composites. The results demonstrate that the inclusion of carbon black as filler enhances the physical properties of the PLA-carbon composites, including tensile properties, hardness, and density. The addition of carbon black also leads to improved electrical conductivity of the composites. Better enhancement toward the electrical properties of PLA-carbon composites is observed with 1wt% of carbon black in N774 grade. The N550 grade with 2wt% of carbon black shows better improvement in the physical properties of PLA-carbon composites, achieving 10.686 MPa in tensile testing, 43.330 in shore D hardness test, and a density of 1.200 g/cm3 in density measurement. The findings suggest that PLA-carbon composites have the potential for enhanced performance in various industrial applications, particularly in sectors requiring improved physical and electrical properties.

• Journal of Microbiology and Biotechnology
• /
• v.34 no.5
• /
• pp.1017-1028
• /
• 2024

Lignocellulolytic enzymes play a crucial role in efficiently converting lignocellulose into valuable platform molecules in various industries. However, they are limited by their production yields, costs, and stability. Consequently, their production by producers adapted to local environments and the choice of low-cost raw materials can address these limitations. Due to the large amounts of olive stones (OS) generated in Morocco which are still undervalued, Penicillium crustosum, Fusarium nygamai, Trichoderma capillare, and Aspergillus calidoustus, are cultivated under different fermentation techniques using this by-product as a local lignocellulosic substrate. Based on a multilevel factorial design, their potential to produce lignocellulolytic enzymes during 15 days of dark incubation was evaluated. The results revealed that P. crustosum expressed a maximum total cellulase activity of 10.9 IU/ml under sequential fermentation (SF) and 3.6 IU/ml of β-glucosidase activity under submerged fermentation (SmF). F. nygamai recorded the best laccase activity of 9 IU/ml under solid-state fermentation (SSF). Unlike T. capillare, SF was the inducive culture for the former activity with 7.6 IU/ml. A. calidoustus produced, respectively, 1,009 ㎍/ml of proteins and 11.5 IU/ml of endoglucanase activity as the best results achieved. Optimum cellulase production took place after the 5th day under SF, while ligninases occurred between the 9th and the 11th days under SSF. This study reports for the first time the lignocellulolytic activities of F. nygamai and A. calidoustus. Furthermore, it underlines the potential of the four fungi as biomass decomposers for environmentally-friendly applications, emphasizing the efficiency of OS as an inducing substrate for enzyme production.

• The Journal of the Convergence on Culture Technology
• /
• v.10 no.4
• /
• pp.495-499
• /
• 2024

This article summarizes the importance, definition, key strategies and future directions of sustainable packaging design.In modern society, sustainable packaging design is not only concerned with environmental protection and resource conservation, but also involves economic, social and cultural sustainable development.This paper explores strategies to reduce environmental burden and promote ecological balance by using environmentally friendly materials, optimizing packaging design, improving packaging recyclability and reuse. In addition, the article emphasizes the importance of design innovation, such as adopting a simplified design concept and modular system, as well as increasing the versatility of packaging.It also explores the application of life cycle assessment in packaging design to ensure that every step from design to disposal minimizes environmental impact. Finally, despite the environmental and social benefits that sustainable packaging design brings, it still faces technical, economic and regulatory challenges in practice.Future design will require interdisciplinary collaboration, integration of advanced technologies, consumer education and engagement, and enhanced policy and standard-setting to promote widespread adoption and practice of sustainable packaging.