• Applied Biological Chemistry
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• v.19 no.1
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• pp.1-23
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• 1976

The female moths of Lepidoptera comprising over 1,000,000 described species possess long-chain unsaturated alcohols or esters as the typical structure of potential sex attractants. In this experiment, various stereoisomers of $C_{16}-unsaturated$ acetates were synthesized for potential sex attractants; e.g., $CH_3(CH_2)_mCH=CH(CH_2)_nOR$ (m=0-12, n=1-13, R=H and $-COCH_3$). Seventeen acetates were spectrometrically examined so that the data would provide a ready catalog of gas chromatography and mass spectrometric data for comparison with natural insect sex attractants. Exclusively cis and trans isomers were obtained by the catalytic and chemical reduction methods, respectively. Commercially available $CH_3(CH_2)_mBr,\;CH_3(CH_2)_mC{\equiv}CH,\;HC{\equiv}C(CH_2)_nOH\;and\;HO(CH_2)_n\;OH$ were used for the synthetic starting material. 1-Alkynes, $CH_3(CH_2)_m\;C{\equiv}CH$ exceeding nine methylene groups did not condense with alkyl dihalides. The yield of coupling products was gradually decreased with increasing the molecular weight of diols. In the coupling reaction of $BrCH_2CH_2$ OTHP with acetylene gas, the tetrahydropyranyl ether of bromohydrin produced undesirable elimination product. In this experiment, it seems that p-toluenesulfonic acid is greatly favoured hydrolyzing agent over dilute sulfuric acid in the hydrolysis of the tetrahydropyranyl ether of long-chain alkynols.

• Applied Biological Chemistry
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• v.24 no.2
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• pp.85-93
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• 1981

For the utilization of natural cellulosic materials by microorganisms, a potent cellulase-producing microorganism was isolated and identified as Trichoderma spp. Rice straw used as a substrate in this study was preliminarily treated with chemical solvents and/or additionally treated with acids and by heat, and then examined with the cellulase produced by the organism. Better results in sugar production by decomposing the straw cellulose were obtained, when the cellulase was produced by cultivating the organism in the selection medium, pH 5.0, for 5 days, and when the pretreated straw substrate was additionally treated with 0.1% $H_2SO_4$ sulfuric acid at $120^{\circ}C$ for 1 hour. The enzyme production was increased by about 20%, when 0.5% urea 0.5% phosphate, 0.1% meat extract, or 5% orange peel was added into the culture medium. For the practical purposes, the sugar production from the rice straw by the cellulase-producing microorganism can be improved by extending the reaction time of the enzyme up to 24 hr or longer.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.4
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• pp.202-207
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• 2009

Nanocomposite formation of metal-metal oxide systems by mechanical alloying (MA) has been investigated at room temperature. The systems we chose are the $Fe_3O_4$-M (M = AI, Ti), where pure metals are used as reducing agent. It is found that $Fe/Al_2O_3$ and $Fe/TiO_2$ nanocomposite powders in which $Al_2O_3$ and $TiO_2$ are dispersed in ${\alpha}$-Fe matrix with nano-sized grains are obtained by MA of $Fe_3O_4$ with Al and Ti for 25 and 75 hours, respectively. It is suggested that the shorter MA time for the nanocomposite formation in $Fe/Al_2O_3$ is due to a large negative heat associated with the chemical reduction of magnetite by aluminum. X-ray diffraction results show that the average grain size of ${\alpha}$-Fe in $Fe/TiO_2$ nanocomposite powders is in the range of 30 nm. The change in magnetic properties also reflects the details of the solid-state reduction of magnetite by pure metals during MA.

• Korean Journal of Microbiology
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• v.53 no.3
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• pp.200-207
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• 2017

A new approach to the solubilization of waste activated sludge (WAS) using alginate-quaternary ammonium complex beads was investigated under controlled mild alkaline conditions. The complex beads were prepared by the reaction of sodium alginate (SA) with 3-(trimethoxysilyl)propyl-octadecyldimethylammonium chloride (TSA) in acid solution, followed by crosslinking with $CaCl_2$. Treatment of WAS with SA-TSA complex beads was effective for enhancing the efficacy of WAS solubilization. The highest value of soluble chemical oxygen demand (SCOD) concentration (3,900 mg/L) was achieved after 10 days of treatment with 30% (v/v) SA-TSA complex beads. The WAS solubilization efficacy of the complex beads was also evaluated by estimating the concentrations of volatile fatty acids (VFAs). The maximum value of VFAs was 2,961 mg/L, and the overall proportions of VFAs were more than 75% of SCOD. The main components of VFAs were acetic, propionic, iso-butyric, and butyric acids. These results suggest that SA-TSA complex beads might be useful for enhancing the solubilization of WAS. The potential use of VFAs as the external carbon substrate for the production of polyhydroxyalkanoate (PHA) by a mixed microbial culture (MMC) was also examined. The enrichment of PHA-accumulating MMC could be achieved by periodic feeding of VFAs generated from WAS in a sequencing batch reactor. The composition of PHA synthesized from VFAs mainly consisted of 3-hydroxybutyrate. The maximum PHA content accounted for 25.9% of dry cell weight. PHA production by this process is considered to be promising since it has a doubly beneficial effect on the environment by reducing the amount of WAS and concomitantly producing an eco-friendly biopolymer.

• Journal of the Korean GEO-environmental Society
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• v.10 no.2
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• pp.21-28
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• 2009

A grouting method has been widely used in construction of large-scale structure to reduce permeability and reinforce the ground. If cement and grout material were not mixed well in the injection tip equipment, an opposite flow and interception state of the chemical grouting can occur. McG (Multi-mixing counterflow prevented Grouting, McG) method installed a special grouting device to allow better mixing of the grouting material(above fineness $6,000cm^2/g$) and prevent backward flow. The block of nozzle also diversify powder rate of cement. YSS (Youngil Special Silicate, YSS) that lowers $Na_2O$ and thereby increases durability was developed by gel-forming reaction material. The seepage state and unconfined compressive strength of the injection material using the special injection tip equipment was tested in this study. The results of this study showed that the uniaxial compressive strength, permeability, N-value, TCR and RQD were improved by this method. Engineering characteristics obtained by the special injection tip method will be compared with those by the other method through various field tests from now on.

• The Journal of Internal Korean Medicine
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• v.19 no.2
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• pp.438-450
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• 1998

Pleural effusion means the inflammation of pleura which has a majority of respiratory disease. The main clinical manifestation is pleural effusional pain, dyspnea, cough, fever, etc. and at present the Tuberculous pleural effusion has the most frequency in which exists exudate in our country. And during studying oriental medical treatment about Tuberculous exudative pleural effusional patient, we found the clinical case about The Combination therapy of Chinese traditional and Western medicine at journal of traditional Chinese Medicine and considered it would be help in oriental medical treatment, so we adjust and report now. This study was performed by analyzing the six papers reported centering around the clinical case of The Combination therapy of Chinese traditional and Western medicine in journal of traditional Chinese Medicine published between 1990-1996. As these papers have no mistakes on diagnosis because it obtained pleurocentesis, tuberculin test positive reaction on choicing clinical case, definite results on X-ray, ultrasound as well as clinical basis, so it considers an apt conclusion. The results were as follows: 1. Western medical treatment uses chemical remedy same with pulmonary tuberculosis, and in case of tubercular pleuritis, it needs thoracic duct pyorrhea, and according to simple exudation also operates therapheutic pleural paracentesis. 2. In case of hydrothorax absorption about tuberculous pleural effusion, prescription of purge the heat accumulated in the lung and eliminate the retention of fluid with powerful purgatives shows considerable effects. 3. The latter period treatment of tuberculous pleural effusion needs Supplement qi and active the collaterals, Nourishing yin and clearing heat in addition to Supporting healthy energy to eliminate evils. 4. In case of curing tuberculous pleural effusion, The Combination therapy of Chinese traditional and Western medicine shows more considerable effect than single western medical treatment in absorption of hydrothorax. 5. In case of curing tuberculous pleural effusion, The Combination therapy of Chinese traditional and Western medicine shows more considerable effect than single western medical treatment in prevention of disease reappearance. 6. In case of curing tuberculous pleural effusion, The Combination therapy of Chinese traditional and Western medicine shows more considerable effect than single western medical treatment in vitality recovery at the latter period of disease.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.2
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• pp.216-222
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• 1989

Water adsorption characteristics and lipid rancidity of fresh and roasted Peanuts were investigated at $25{\sim}60^{\circ)C$ and $11{\sim}85%$ relative humidity. peanuts of 50g were reached to the equilibrium water content in 14 days at $40^{\circ}C$, in 30 days at $25^{\circ}C$, respectively, in all of the relative humidity. BET monolayer water contents were $2.19{\sim}2.69%$ in fresh peanuts and $2.47{\sim}2.67%$ in roasted ones as dry basis at $25{\sim}40^{\circ)C$. Zero order reaction rate of peroxide value(POV) were $8{\sim}21times$ lower as $0.032day^{-1}$ and $0.142day^{-1}$in fresh peanuts than those of $0.663day^{-1}$ and $1.120day^{-1}$ in roasted peanuts at water activity of 0.51, but those were showed the relatively smaller differences according to the water activity and temperature. The critical peroxide value(POV) and carbonyl value(CV) were determined as 15.0meq/kg and 4.7meq/kg at $60^{\circ}C$ $0.51a_w$ by the regression analysis between chemical and sensory evaluation.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.2
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• pp.238-246
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• 1996

High-density SiC-AIN solid solutions were fabricated from powder mixtures of $\beta$-SiC and AIN by hot-pressing in the 1870 to $2030^{\circ}C$ temperature range. The reaction of AIN and $\beta$-SiC (3C) powder transformed to the 2 H (wurzite) structure appeared to depend on the temperature and SiC/A1N ratio and seeds present. The crystalline phases consisted of a SiC-rich solid-solution phase and an A1N-rich solid-solution phase. At $2030^{\circ}C$ for 1 h, for a composition of 50 % AIN/50 % SiC with a seeding of $\alpha$-SiC, the complete solid solution could be obtained and the microstructures are equiaxed with a relatively homogeneous grain size of 2 H phases. The variation of the seeding of $\alpha$-SiC in SIC-A1N solid solutions could be attributed to the transformation behaviour and differences in size and shape of the grains, as well as to other factors, such as grain size distributions, compositional inhomogeneity, and structural defects.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.4
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• pp.157-161
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• 2006

InGaN layers on GaN templated sapphire (0001) substrates were grown by mixed-source hydride vapor phase epitaxy (HVPE) method. In order to get InGaN layers, Ga-mixed In metal and $NH_3$ gas were used as group III and group V source materials, respectively. The InGaN material was compounded from chemical reaction between $NH_3$ and indium-gallium chloride farmed by HCl flowed over metallic In mixed with Ga. The grown layers were confirmed to be InGaN ternary crystal alloys by X-ray photoelectron spectroscopy (XPS). In concentration of the InGaN layers grown by selective area growth (SAG) method was investigated by the photoluminescence (PL) and cathodoluminescence (CL) measurements. Indium concentration was estimated to be in the range 3 %. Moreover, as a new attempt in obtaining InAlGaN layers, the growth of the thick InAlGaN layers was performed by putting small amount of Ga and Al into the In source. We found the new results that the metallic In mixed with Ga (and Al) as a group III source material could be used in the growth process of the In(Al)GaN layers by the mixed-source HVPE method.

• Journal of the Korean Ceramic Society
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• v.34 no.2
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• pp.216-224
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• 1997

Porous silica ceramics were prepared(with HCI catalyst) using H2O/TEOS molar ratios of 2.6~59.0, with the EtOH/TEOS ratio fixed. After preparing 9 kinds of sol, the followings were investigated; measurement of the gelation time, thermal analyses by TG/DTA, property analyses of the intermediates by FT-IR and X-ray diffractometry with dried samples, analyses of SiO2 polymer by FT-IR, the investigation of specific sur-face area and pore size distribution by N2-adsorption isotherm, and structural change of SiO2 polymer and pore morphology by TEM observation, with samples heat-treated to 50$0^{\circ}C$. In the concentrations of in-vestigated compositions and catalyst, gelation time showed a minimum at ca. 11 moles of water per one mole of TEOS, the highest degree of polymerization at ca. 8-18 moles, and the largest specific surface area at ca. 11 moles, which means that the polymerization proceeded fastest at ca. 11 moles of water. In con-clusion, the more water used, the faster the polymerization reaction up to ca. 11 moles, but more than ca. 11 moles of water caused retardation of gelation and resultant reduction of specific surface area.