• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 2000년도 Proceedings of 2000 International Nano Crystals/Ceramics Forum and International Symposium on Intermaterials
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• pp.151-163
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• 2000

A polymerized organic-inorganic complexation route is introduced for the synthesis of oxide ceramic powders. Polyvinyl alcohol was used as the organic carrier for precursor ceramic gel. Porous and soft powders, which have a high specific surface area, were obtained after calcinating the aerated precursors. The PVA content and its degree of polymerization had a significant influence on the homogeneity of the final powder. In particular, attrition milling process with the porous powder resulted in ultra-fine particles. In the case of the preparation of cordierite powder, nano-size powder, which has a high specific surface area of 181 ㎡/g, was obtained by the milling process. The complexation route was also applied to the synthesis of unstable phase in room temperature like beta-cristobalite, high temperature form of silica.

• 한국유기농업학회지
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• 제5권1호
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• pp.111-124
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• 1996

Composting of animal residues with weeds and waste papers as bulking agents was tested. Coorperative form of work with farmers, students, cleaning women and members of citizens' movement was attempted. The responses of participants for composting, through it's laboriousness and dirtiness, were favorable with feeling of doing good for social services. The temperature of compost was raised up to 83 $^{\circ}C$. in spite of cold winter weather after turning. The pH, water content, total carbon, total nitrogen and C/N ratio showed the similarity to stability steps of other usual composts. The contents of heavy metals were low except Cu in comparison with standard levels. The uses of waste papers as a bulking agent for composting of animal residues, especially for organic farming, would need more diverse investigations.

• 한국식품영양과학회지
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• 제20권1호
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• pp.52-58
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• 1991

Physico-chemical properties including the composition of organic acids and fatty acids in native bee-honey and foreign bee-honey harvested in Kangwon area were studied with the emphasis on the honey which was collected form wild flowers nd mixed flowers sources for honey nectars. the major organic acids were considered as acetic acid formic acid and valeric acid in volatile acids and gluconic acid maleic acid malic acid quinic acid and citric acid in non-volatile fraction in both of native bee-honey and foreigr bee-honey. Some naturally occuring fatty acids({{{{ { C}_14{ } }}}}-{{{{ {C }_{20 } }}}}) were observed with the principal fatty acids of myristic aicd linolenic acid and palmitic acid and palmitic acid in the various honey, The characteristics of moisture content pH viscosity free acidity lactone and total acidity were also analyzed and discussed.

• 한국환경보건학회지
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• 제27권3호
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• pp.43-48
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• 2001

Terephthalic acid and ethylene glycol resulting form the weight-reduction process of polyester make trouble in the operation of activated sludge process. Also, polyester weight loss wastewater shows high pH, high organic strength and wide variation of organic loading. Therefore, this study was conducted in order to improve treatment efficiency by activated sludge process with Pseudomonas sp degrading components of polyester weight loss wastewater. The CO $D_{Mn}$ and BO $S_{5}$ of the waste wastewater were 560~3,000 mg/$\ell$ and 8000~3,000 mg/$\ell$, respectively. pH was 11.8~12.3. COD removal efficiency by activated sludge-coagulation process with Pseudomonas sp was 94.1~95.8% for 35 hr of hydraulic retention time. Total organic carbon removal efficiency was 97.1%. Ethylene glycol and terephthalic acid in the wastewater were completely degraded during 32 hr of hydraulic retention time.e.

• 한국대기환경학회지
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• 제16권2호
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• pp.103-112
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• 2000

Elemental carbon(EC) and organic carbon(OC) in fine particles (PM2.5) were collected from October 1995 through August 1996 in the Chongju area. The annual mean concentrations of EC and OC were 4.44 and 4.99 $\mu\textrm{g}$/m3 respectively. EC showed seasonal variation (p<0.01) The magnitude of the seasonal mean EC concen-tration progresses in the following manner : fall>winter>spring>summer. However OC was not statistically seasonal difference(p=0.20) The annual average OC/EC ratio was 1.12 suggesting that organic carbon measured may by emitted directly in particulate form(primary aerosol) The contribution of EC to PM2.5 mass follows a general pattern in which fall(14.6%) > winter (9.8%) >spring(7.8%) =summer(7.8%) and the contribution of OC to the PM2.5 mass varies in order fall(13.8%) >winter(11.3%) >spring(10.5%) >summer (9.4%) Total carbona-ceous particles(EC and OC) accounted for 17-28% of the PM2.5 mass.

• 약학회지
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• 제22권1호
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• pp.27-32
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• 1978

Metoclopramide reacts with ammonium cobaltothiocyanate to form a stable ion pair which has an absorption maximum of 625mm. The reaction product was insoluble in water but soluble in most organic solvents. 1,2-Dichlorethane was the best extracting solvent among the several organic solvents tested. Metoclopramide can be determinded not only by visible light spectrophotometry but also indirectly by estimation of cobalt in the organic phase by flameless atomic absorption spectrophotometry. Linear relationship was found between absorbance and concentration in the range of 10$^{-4/}$-10$^{-3}$M by spectrophotometry and 10$^{-5}$-10$^{-4}$M by flameless atomic absorption spectrophotometry. The coefficient of variation by spectrophotometry was 0.9% and that of flameless atomic absorption was 1.8%. There was no interference with excipients, pH, temperature and reaction time. With this method, it is possible to determine accurately metoclopramide and tertiary amines in pharmaceutical preparations.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.460-460
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• 2014

Organic photovoltaic cells (OPV) have been extensively studied due to their unique properties such as flexibility, light-weight, easy processability, cost-effectiveness, and being environmental friendly. These advantages make them an attractive candidate for application in various novel fields and promising development with new features. Photovoltaic cell-integrated textiles have greatly attractive features as a power source for the smart textile solutions, and OPV is most ideal form factor due to advantage of flexibility. In this study, we develop a textile-based OPV through various experimental methods and we suggest the direction for the design of the photovoltaic textile. We used a textile electrode and tried to various layouts for textile-based OPV. Finally, we determined the contact area by using Hertzian theory for the calculation of power conversion efficiency (PCE). Based on the results of calculation, the short circuit current density, Isc, was $13.11mA/cm^2$ under AM 1.5condition and the PCE was around 2.5%.

• 한국염색가공학회지
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• 제30권1호
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• pp.1-8
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• 2018

In the present study, three morpholine substituted crystal violet lactone (CVL) have been synthesized to monitor the thermochromic property. This work is explaining the role of substituent on the lactone ring. The methyl substituents induced greater chromic effects than the chloro substituents. Furthermore, the three-component mixtures that contained CVL, bisphenol-A, and methyl stearate were used to analyse the thermochromic effect of the CVLs as bulk samples with various temperature. The thermochromic properties of the CVLs were evaluated using solid-state UV-Vis and FT-IR spectroscopic techniques. Finally, one of the synthesized CVL has been successfully converted into the form of a test paper similar to pH paper for use as thermal indicators.

• 한국유기농업학회지
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• 제6권1호
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• pp.45-50
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• 1997

Cultivation of peach by organic farming and cooperative form of work was attempted. The compost was made from egg shells and bread residues(bakery residues), falling leaves, and weeds. The cooperative teams of work were farmers, students and members of citizens' movement. The responses of participants for composting, though it's laboriousness and dirtiness, were favorable with feeling of doing good for social services. 20 chickens were raised in the peach orchard as one of the mixed farming. The pH and Ca content of ripened compost were 7.7 and 1.57 %, respectively. Controlling Aphids(plant louse)by ladybug was observed vividly. The size and sugar concentration were comparable to standard values even though rainy season and the number of damaged fruits were less than half(40%).

• 약학회지
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• 제27권4호
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• pp.303-307
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• 1983

Pipethanate*HCl reacts with ammonium cobaltothiocyanate to form a stable ion pair which has an absorption maximum at 626nm. The reaction product was insoluble in water but freely soluble in most organic solvents. 1, 2-Dichloroethane was the best extracting solvent among the several organic solvents. Pipethanate*HCl can be determined not only by the spectrophotometry but also inderectly by estimation of cobalt in the organic phase by atomic absorption spectrophotometry. Linear relationship was found between absorbance and concentration in the range of $1.0{\times}10^{-3}~4.0{\times}10^{-3}M$ by spectrophotometry and $1.5{\times}10^{-4}~4.0{\times}10^{-4}M$ by atomic absorption spectrophotometry. With this method it was possible to determine pipethanate$\cdot$HCl in the pharmaceutical preparations.