• Journal of Mushroom
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• v.21 no.3
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• pp.185-189
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• 2023

This study was conducted to develop a renewable and sustainable bio-material to replace polystyrene (EPS) in fungal-mycelium-based composite using agricultural by-products. Four mushrooms (Ganoderma lucidum, Fomitella fraxinea, Phellinus linteus, and Schizophyllum commune) were cultured in an oak sawdust plus rice bran substrate to select the mushroom with the best growth. The mycelia of G. lucidum showed the best growth. To investigate the optimal mixing ratio with spent mushroom substrate (SM) and oak sawdust (OS), samples were prepared by mixing SM and OS at ratios of 50%:50%, 60%:40%, and 80%:20% (w/w). Each substrate was then inoculated with G. lucidum. G. lucidum showed the best mycelial growth of 140.0 mm in the substrate with SM and OS mixed at a 60%:40% ratio. It was also found that the substrate with SM and OS mixed at a 60%:40% ratio had the best handling properties. The compressive strength of mycelial materials inoculated with G. lucidum was in the range of 300-302 kgf mm^-1, and the materials were four times stronger than polystyrene materials. These results indicate that substrates comprising spent mushroom substrate mixed with oak sawdust can be successfully upcycled to mycelium-based composite materials using G. lucidum. This represents a sustainable approach.

• Korean Journal of Metals and Materials
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• v.50 no.6
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• pp.469-475
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• 2012

A high-energy mechanical milling (HEMM) process was introduced to improve sinter-ability, and rapid sintering of spark plasma sintering (SPS) under pressure was used to make ultra fine grain (UFG) of Ti-Nb-Mo-CPP composites, which have bio-attractive elements, for increasing mechanical properties. Ti-Nb-Mo-CPP composites were successfully fabricated by SPS at $1000^{\circ}C$ within 5 minutes under 70 MPa using HEMMed powders. The Vickers hardness of the composites increased with increased milling time and addition of CPP contents. Biocompatibility and corrosion resistance of the Ti-Nb-Mo alloys were improved by addition of CPP, and the Ti-35%Nb-10%Mo-10%CPP alloy had better biocompatibility and corrosion resistance than the Ti-6Al-4V ELI alloy.

• Membrane and Water Treatment
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• v.5 no.4
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• pp.265-279
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• 2014

Pervaporation is the most promising technique for the recovery of ethanol from the fermentation system. To date, extensive research has been conducted on the exploration of membrane materials with favorable properties. In this paper, we primarily review the performance of adsorbent-filled rubbery membranes. In addition, the fundamental mechanisms of ethanol and water molecules transportation through composite membranes are demonstrated, particularly from the perspective of cluster formation. Finally, future prospects are also analyzed to develop the guidelines for the future development of excellent membrane materials for ethanol concentration. This paper is not meant to be an exhaustive overview, rather a specialized summary that allows readers to select the information appropriated to their topics.

• Vacuum Magazine
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• v.4 no.2
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• pp.15-23
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• 2017

This article reviews technical trend in research of stretchable electrodes for wearable devices, bio-integrated devices, and stretchable electronics. Stretchable electronics is new emerging class of electronics following flexible electronics. One of the most difficult challenges in the development of stretchable electronic is to realize high performance stretchable electrodes with a low resistivity and high strain failure and stretchability against severe strain of the substrate. For this reason, there are many reports on the promising stretchable electrodes including CNT, graphene, Ag nanowire, and composite materials. We outline the recent research for stretchable substrate and stretchable electrode materials to realize highly stretchable electrodes.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.4
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• pp.51-60
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• 2017

Bottom ash(BA) from coal-fired power plants is burnt and remaining ash at high temperature. Since the BA is baked at high temperature, it is considered to be the same function as the elvan. Nowadays, the demand for mortar with far infrared rays, antibacteria, antifungus, deodorization, aridity and humidity function is increasing as the materials such as Hwangtoh(yellow soil) and elvan rather than general mortar. As a result of comparing the functionality of eco-friendly bio BA mortar with that of general mortar, the far infrared ray emissivity is about $0.02{\times}10^2W/m^2$ more and the deodorization function is about 26% or more. Even in the case of humidity control, BA motors showed about 1.8 times higher than general mortar, and more than 10% higher than the "good" standards of moisture absorption and damp proofing construction materials established by the Ministry of Land, Transport and Maritime Affairs.

• Journal of the Korean Wood Science and Technology
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• v.32 no.5
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• pp.29-38
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• 2004

In this study, we investigated the thermal properties of corn-starch filled polybutylene succinate-adipate (PBS-AD) bio-composites. Thermal analysis (TA) is used to describe the analytical method for measuring the chemical property and weight loss of composite materials as a function of temperature. The thermal stability of corn-starch was lower than that of pure PBS-AD. As corn-starch loading increased, the thermal stability and degradation temperature of the bio-composites decreased and the ash content increased. It can be seen that the degree of compatibility and interfacial adhesion of the bio-composites decreased because of the increasing mixing ratio of the corn-starch. As the content of corn-starch increased, there was no significant change in the glass transition temperature (T_g) and the melting temperature (T_m) for the bio-composites. The storage modulus (E') and loss modulus (E") of the corn-starch flour filled PBS-AD bio-composites were higher than those of PBS-AD, because of the incorporation of corn-starch increased the stiffness of the bio-composites. At higher temperatures, the decreased storage modulus (E') of bio-composites was due to the increased polymer chain mobility of the matrix polymer. From these results, we can expect that corn-starch has potential as a reinforcing filler for bio-composites. Furthermore, we recommend using a coupling agent to improve the interfacial adhesion between corn-starch and biodegradable polymer.

• Composites Research
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• v.23 no.1
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• pp.1-7
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• 2010

In this paper, finite element analyses for estimating the behavior of fractured femur just after the operation were carried out by using ABAQUS 6.71. A stainless steel bone plate and composite bone plates with various stacking angles were considered to find out the effect of bone plate properties on bone fracture healing. In order to simulate the actual state, contact conditions between the plate and bone and fractured bones were imposed on the finite element models and the whole analysis was divided by two steps; screw fastening step and load bearing step. The stress and strain distributions at the fracture site for the cases of the stainless steel and composite bone plates were analyzed and compared with. From the analyses it was found that the composite bone plate had potential advantages for effective bone fractures healing relieving stress shielding effect.

• The Journal of Korean Academy of Prosthodontics
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• v.53 no.4
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• pp.318-324
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• 2015

Purpose: This study compared shear bond strengths of five self-adhesive cements with phosphate monomer to zirconium oxide ceramic with and without airborn particle abrasion. Materials and methods: One hundred zirconia samples were air-abraded ($50{\mu}mAl_2O_3$). One hundred composite resin cylinders were fabricated. Composite cylinders were bonded to the zirconia samples with either Permacem 2.0 (P), $Clearfil^{TM}$ SA Luting (C), $Multilink^{(R)}$ Speed (M), $RelyX^{TM}$ U200 Automix (R), G-Cem $LinkAce^{TM}$ (G). All bonded specimens were stored in distilled water ($37^{\circ}C$) for 24 h and half of them were additionally aged by thermocycling ($5^{\circ}C$, $55^{\circ}C$, 5,000 times). The bonded specimens were loaded in shear force until fracture (1 mm/min) by using Universal Testing Machine (Model 4201, Instron Co, Canton, MA, USA). The failure sites were inspected under field-emission scanning electron microscopy. The data was analyzed with ANOVA, Tukey HSD post-hoc test and paired samples t-test ($\alpha$=.05). Results: Before and after thermocycling, $Multilink^{(R)}$ Speed (M) revealed higher shear-bond strength than the other cements. G-Cem $LinkAce^{TM}$ (G) showed significantly lower bond strengths after thermocycling than before treatment (P<.05), but the other groups were not significantly different (P>.05). Conclusion: Most self-adhesive cements with phosphate monomer showed high shear bond strength with zirconia ceramic and weren't influenced by thermocycling, so they seem to valuable to zirconia ceramic bonding.

• Journal of the Korean Chemical Society
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• v.54 no.1
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• pp.137-141
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• 2010

Generally, polymer materials are not air-permeable and hydrophilic. In addition, they do not possess anti-fungal property. Hydrophilicity, air-permeability, and anti-fungal properties of new composites consisting of polymer, ceramic nanoparticles, and silver ion were investigated by contact angle measurements, air permeation time, and cell culture. The hydrophilic, air-permeable, and anti-fungal composites can be used in health care industry.

• Environmental Engineering Research
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• v.24 no.2
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• pp.354-361
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• 2019

Renewable energy from biomass and biodegradable wastes can significantly supplement the global energy demand if properly harnessed. Pyrolysis is the most profound modern technique that has proved effective and efficient in the energy conversion of biomass to yield various products like bio-oil, biochar, and syngas. This study focuses on optimization of slow pyrolysis of banana peels waste to yield banana peels vinegar, tar and biochar as bio-infrastructure products. Response surface methodology using central composite design was used to determine the optimum conditions for the banana wastes using a batch reactor pyrolysis system. Three factors namely heating temperature ($350-550^{\circ}C$), sample mass (200-800 g) and residence time (45-90 min) were varied with a total of 20 individual experiments. The optimal conditions for wood vinegar yield (48.01%) were $362.6^{\circ}C$, 989.9 g and 104.2 min for peels and biochar yield (30.10%) were $585.9^{\circ}C$, 989.9 g and 104.2 min. The slow pyrolysis showed significant energy conversion efficiencies of about 90% at p-value ${\leq}0.05$. These research findings are of primary importance to Uganda considering the abundant banana wastes amounting to 17.5 million tonnes generated annually, thus using them as pyrolysis feedstock can boost the country's energy status.