• Journal of Mushroom
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• v.7 no.1
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• pp.27-36
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• 2009

Pleurotus ferulae is an edible mushroom found on a medicinal plant, Ferula assa-foetida, in centeral China. This study was carried out to investigate the cultural characteristics of P. ferulae strains. Characteristics of mycelial growth were investigated for 5 strains of P. ferulae. All the 5 strains showed the best mycelial growth at $25^{\circ}C$ and their growth rate was very low at $35^{\circ}C$. The colony diameter reached to 45~72 mm after 7 days at $25^{\circ}C$. Malt extract agar medium was the best for mycelial growth of the species both in hyphal length and density. Mycelial growth was not affected by various pH from 6.0 to 8.0. An optimal carbon source was arabinose and an optimal nitrogen one was arginine. And an effective substrate for the mycelial growth was 8 to 2 mixture of oak sawdust and cottonseed meal.

• Journal of Mushroom
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• v.9 no.4
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• pp.166-169
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• 2011

In this study we carried out to find suitable nutrient supplement of corncob as a main carbon source for bottle culture of oyster mushroom. Data from chemical analysis of Kapok seed cake(KP) treatment showed 20.2 of C/N ratio, $0.28g/cm^3$ of bulk density and 74.2% of porosity. Mushroom yield of KP treatment is 158g/bottle that is similar to control(150g/bottle). However, the price of KP is 400 won/kg that is cheaper than 550 won/kg of cotton seed cake(CS). The highest REV(relative feed value) also was observed KP treatment. A further study is required determine practical animal performance by feeding the corncob-based KP.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.108-109
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• 2012

This talk will begin with the demonstration of facile synthesis of silicon nanostructures using the magnesiothermic reduction on silica nanostructures prepared via self-assembly, which will be followed by the characterization results of their performance for energy storage. This talk will also report the fabrication and characterization of highly porous, stretchable, and conductive polymer nanocomposites embedded with carbon nanotubes (CNTs) for application in flexible lithium-ion batteries. It will be presented that the porous CNT-embedded PDMS nanocomposites are capable of good electrochemical performance with mechanical flexibility, suggesting these nanocomposites could be outstanding anode candidates for use in flexible lithium-ion batteries. Directed self-assembly (DSA) of block copolymers (BCPs) can generate uniform and periodic patterns within guiding templates, and has been one of the promising nanofabrication methodologies for resolving the resolution limit of optical lithography. BCP self-assembly processing is scalable and of low cost, and is well-suited for integration with existing semiconductor manufacturing techniques. This talk will introduce recent research results (of my research group) on the self-assembly of Si-containing block copolymers for the achievement of sub-10 nm resolution, fast pattern generation, transfer-printing capability onto nonplanar substrates, and device applications for nonvolatile memories. An extraordinarily facile nanofabrication approach that enables sub-10 nm resolutions through the synergic combination of nanotransfer printing (nTP) and DSA of block copolymers is also introduced. This simple printing method can be applied on oxides, metals, polymers, and non-planar substrates without pretreatments. This talk will also report the direct formation of ordered memristor nanostructures on metal and graphene electrodes by the self-assembly of Si-containing BCPs. This approach offers a practical pathway to fabricate high-density resistive memory devices without using high-cost lithography and pattern-transfer processes. Finally, this talk will present a novel approach that can relieve the power consumption issue of phase-change memories by incorporating a thin $SiO_x$ layer formed by BCP self-assembly, which locally blocks the contact between a heater electrode and a phase-change material and reduces the phase-change volume. The writing current decreases by 5 times (corresponding to a power reduction of 1/20) as the occupying area fraction of $SiO_x$ nanostructures varies.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.479-486
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• 2008

The cultural characteristics and antibacterial activities of Cordyceps militaris and Paecilomyces tenuipes were compared. The mycelial growth was the highest on MCM (Mushroom Complete Medium) for C. militaris and on YMA (Yeast Malt Agar) for P. tenuipes. But the mycelial density on MMM (Mushroom Minimal Medium) was lower than other on media. The optimum mycelial growth was observed at $25^{\circ}C$. C. militaris was low mycelial growth when it was transferred over 5 times generation. The carbon source for the optimum mycelial growth was fructose of monosaccharide, maltose of disaccharide and dextrin of polysaccharide. The calcium nitrate of organonitrogen was found the best mycelial growth on C. militaris, while the sodium nitrate observed to be well for mycelial growth on P. tenuipes. The ammonium tartrate was observed to be the best among the inorganonitrogen used for mycelial growth. Antibacterial activities were found out just C. militaris against Bacillus cereus of Gram (+).

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.1
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• pp.10-15
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• 2005

Effects of CH₄/H₂ flow rate ratio, chuck bias and microwave power on the structural properties and particle densities of diamond thin films deposited on Ti substrates in microwave plasma CVD were examined. High quality diamond thin films were deposited on Ti substrates in 2∼3 CH₄ Vol.% conditions due to the preferential formation of sp³-bonus ana selective removal of sp²-bonus in the CH₄/H₂ mixtures, and the mechanism for the formation of diamond particles on Ti was analysed. Diamond particle density increased with increasing negative chuck bias to Ti substrate due to bias-enhanced nucleation of diamond and the threshold voltage was found at ∼-50 V. With increasing microwave power the evolution from micro-crystalline graphite layer to diamond layer was observed.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.17 no.6
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• pp.277-282
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• 2007

The artificial lightweight aggregate (ALA) was manufactured using coal bottom ashes produced from a thermoelectric power plant with clay and, the sintering temperature and batch composition dependence upon physical properties of ALA were studied. The bottom ash (BA) had 13wt% coarse particle (>4.75mm) and showed very irregular shape so should be crushed to fine particles to be formed with clay by extrusion process. Also the bottom ash contained a many unburned carbon which generates the gas by oxidation and lighten a aggregate during a sintering process. Plastic index of green bodies decreased with increasing bottom ash content but the extrusion forming process was possible for the green body containing BA up to 40wt% whose plastic index and plastic limit were around 10 and 22 respectively. The ALA containing $30{\sim}40wt%$ BA sintered at $1100{\sim}1200^{\circ}C$ showed a volume specific density of $1.3{\sim}1.5$ and water absorption of $13{\sim}15%$ and could be appled for high-rise building and super-long bridge.

• Korean Chemical Engineering Research
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• v.54 no.5
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• pp.693-697
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• 2016

In this study, we fabricated the catalysts for enzymatic biofuel cell anode with carbon nanotube (CNT), glucose oxidase (GOx) and various molecular weights branched poly(ethyleneimine)(bPEI) and terephthalaldehyde (TPA) as cross-linker. In case of GOx/bPEI/CNT using only physical entrapments for immobilization, the molecular weights of bPEI didn't affect to electrochemical performances and long term stability. but that of the catalysts cross linked via TPA (TPA[GOx/bPEI/CNT]) improved and the mass transfer of glucose to FAD was interrupted as increasing of the bPEI's molecular weights. Furthermore, it was confirmed that the optimum molecular weight of PEI for TPA [GOx/bPEI/CNT]) structure is 750k that showed marvelous high performance (maximum power density of $0.995mW{\cdot}cm^{-2}$).

• Journal of the Korean housing association
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• v.27 no.6
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• pp.31-43
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• 2016

The purpose of this paper is to gather information and opinions to better guide the direction for implementing improvements of the senior centers' indoor environments located in Jeonju residential areas, by surveying the users about the level of satisfaction and analyzing the result in relation to the current situation. Senior centers located in Jeonju residential areas were operating the facilities with low financial support from the local autonomous entity. According to the results of the survey, most of the users tend to use the facilities between 12p.m. to 6p.m., and the majority have lunch at the senior centers. Most of the senior centers already have cooking facilities, without a dining room, except one place, and even the facilities they have are very poor. In a thermal environment area, the temperature is mostly above in summer or below in winter the appropriate temperature, especially the temperature of the restroom of all senior centers are below $20^{\circ}C$ in winter. The density of carbon dioxide is above average in most indoor areas. However, the users' level of facilities' satisfaction was positive. To improve the seniors' quality of life, the local autonomous entity has to start regular check-ups and repair of the poor indoor environment and facilities, with more financial support and active supervision by senior center the management.

• Applied Chemistry for Engineering
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• v.27 no.4
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• pp.371-379
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• 2016

In this article, the foamed body of glass was manufactured from the waste borosilicate glass produced by wet pulverization process without additional pretreatment which can be used as a recycling method for waste LCD panel glass. Each 100 g of pulverized waste borosilicate glass with the size of less than 270 mesh were mixed with 0.3 weight fraction of carbon and 1.5 weight fraction of $Na_2CO_3$, $Na_2SO_4$ and $CaCO_3$ and let them foamed for 20 minutes at $950^{\circ}C$ to manufacture the foamed body having the density of less than $0.3g/cm^3$. Additionally, adding $SiO_2$ or $H_3BO_3$ to the mixture enabled the foamed body to have efficient formation of open pores which showed the possibility for producing the foamed body with new functionalities such as sound absorption.

• Korean Journal of Materials Research
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• v.28 no.8
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• pp.459-465
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• 2018

This paper presents a study of the microstructure and mechanical properties of commercial high-hardness armor (HHA) steels tempered at different temperatures. Although the as-received specimens of all the steels exhibit a tempered martensite structure with lath type morphology, the A steel, which has the smallest carbon content, had the lowest hardness due to reduced solid solution hardening and larger lath thickness, irrespective of tempering conditions. As the tempering temperature increases, the hardness of the steels steadily decreases because dislocation density decreases and the lath thickness of martensite increases due to recovery and over-aging effects. When the variations in hardness plotted as a function of tempering temperature are compared with the hardness of the as-received specimens, it seems that the B steel, which has the highest yield and tensile strengths, is fabricated by quenching, while the other steels are fabricated by quenching and tempering. On the other hand, the impact properties of the steels are affected by specimen orientation and test temperature as well as microstructure. Based on these results, the effect of tempering on the microstructure and mechanical properties of commercial high-hardness armor steels is discussed.