• Journal of Nutrition and Health
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• v.28 no.11
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• pp.1049-1055
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• 1995

This study was designed to investigate the effects of calcium supplementation on calcium metabolism in seven healthy college women, aged from 19 to 21 years old. For this purpose, metabolic studies were conducted for two weeks. During the first week, the subjects ate experimental diet which nutrients composition was similar to their usual intake. And during the consecutive second week, they ate the same experimental diet supplemented with 500mg of calcium daily. The results were summarized as follows ; 1) Fecal excretion of calcium increased significantly (P<0.05), but urinary excretion of that did not show any change after supplementary intake of calcium. 2) Mean apparent calcium absorption was 28.5% and retention was 182mg/day when subjects ate the experimental diet without calcium supplementation. Calcium retention was significantly ate the experimental diet without calcium supplementation. Calcium retention was decreased to 24.1% by additional intake of calcium. 3) Phosphorus balance did not show any change after additional intake of calcium. 4) Serum calcium level was also not changed by additional intake of calcium. 5) Serum calcium level increased significantly(P<0.05) but serum phosphorus level did not show any change after additional intake of calcium. The above results showed that supplementation of 500mg calcium daily can be helpful to increase calcium retention as well as the peak bone mass in young women eating usual Korean diets.

• Journal of Veterinary Clinics
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• v.16 no.2
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• pp.257-264
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• 1999

The objective of this study was to estimate the possibility of use as a crude feed about Korean pine foliage. Foliage was fermented aerobic and anaerobic state. And then, it was fed Korean native bull 5 to 6 month old. Bulls were fed control (n=4), aerobic fermented (n=4) and anaerobic fermented (n=4) feed 30 percent of total ration. Bulls were examined with blood sample and body weight on day 0, 60, 120 and 180. There were no differences on complete blood cell count serum chemistry and incidence of disease among groups for experiment period. Also, electrolytes (Ca, Mg, P) balance were good condition. Experimental feed did not induced toxicosis in kidney and liver, Fermented foliage and leaves of Korean softwood were efficient crude feed in carbohydrate, fat and protein metabolism. Experimental feed induced growth of Korean native bull body weight in growing stage without retard. In addition to anaerobic fermented feed has a more higher growth rate than control feed. Our conclusion is that fermented softwood substitute some part of ration, minimum 30 percent, in growing stage of a Korean native bull.

• Magazine of the Korea Concrete Institute
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• v.8 no.3
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• pp.157-165
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• 1996

The purpose of this study is to develop the epoxy-modified mortars and concretes without hardener having a good balance between performance and cost. In this study, the epoxy-modified and concretes without and with the hardener are prepared with various polymer-cement ratios, and tested for the mechanical properties of the epoxy-modified mortars and concretes without and with the hardener. From the test results, the epoxy-modified mortars and concretes without the hardener having an excellent mechanical properties are developed at low polymer-cement ratios of 10 to 20% compared with those of conventional epoxy-modified mortars and concretes with the hardener.

• Korean Journal of Veterinary Research
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• v.31 no.4
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• pp.425-431
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• 1991

Effects of recombinant bovine somatotropin$({\gamma}BST)$ on mineral composition of milk were investigated in Twenty-five multiparous Holstein dairy cows. Recombinant BST was administered by two different routes; intramusculary(12.5mg and 25mg/day) and subcutaneously (500mg and 750mg) in sustained-release vehicle every 2 weeks beginning 4 week postpartum and continuing for 7 months. Milks were collected 0,1,2,3,5 and 7 months after beginning of treatments in control and ${\gamma}BST$-administered groups. Mineral composition, such as Ca, Pi, Na, K, Mg, Zn, Fe and Mn, in milk were not affected by the administration of ${\gamma}BST$ regardless of dose and dosage forms. It is concluded from the observations of these experiments that the dose and dosage forms of ${\gamma}BST$ employed in this work might not affect milk mineral composition in dairy cows under the normal sanitary condition and adequate nutrient balance.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.450-452
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• 2004

Using factor analysis and bivariate comparisons of major components in ground water, three geochemical processes were identified as controlling factors of ground water chemistry; 1) natural mineralization by water rock interactions, 2) effect of seawater which includes salinization by seawater near seashores and deposition of sea salt, and 3) nitrate contamination by N fertilization. Contribution of rainfall was also estimated from the measured composition of wet deposition. The geochemical processes were separated using total alkalinity as an indicator for natural mineralization, Cl for effect of seawater, and nitrate for N fertilization. Relatively high correlation of major components with nitrate suggests that nitrification of nitrogenous fertilizers significantly affects ground water chemistry. Total cations derived from nitrate sources have good linearity for nitrate in equivalent basis with a slope of 1.8, which is a mean of proton production coefficients in nitrification of two major compounds in nitrogenous fertilizers, ammonium and urea. Contribution of nitrate sources to base cations, Cl, and SO$_4$ in ground water was determined considering maximum contribution of natural mineralization to estimate a threshold of the effect of N fertilization for ground water chemistry, which shows W fertilization has a greatest effect than any other processes in ground water with nitrate concentration greater than 50 mg/L for Ca, Mg, Na and with concentration greater than 30 mg/L for Cl and SO$_4$.

• Proceedings of the KAIS Fall Conference
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• 2009.05a
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• pp.848-850
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• 2009

화석에너지 고갈로 인한 유가 상승으로 폐기물 에너지화가 이슈화 되고 있다. 폐기물 고형 연료 RDF는 에너지 문제를 해결하기위한 대안 중 하나로 수송성, 저장성, 연소안정성이 우수하나 환경오염 물질의 발생이 문제가 된다. 이러한 오염물질을 처리하기 위한 배가스 오염 물질처리를 위한 plant 설비 비용과 시간이 많이 투자된다. Aspen plus는 mass energy balance와 화학적평형, 열역학을 이용하여 공정 모사를 할 수 있는 프로그램으로 검증되었다. RDF의 삼성분, 원소분석, 발열량을 입력을 통해 HCl, SOx, NOx, CO의 배출량을 예측하고 이에 맞는 SNCR, SDA 등과 같은 반응기를 적용 하므로써 다양한 배가스 처리를 모사 할 수 있다. NOx를 제어하기위에 urea주입과 SOx와 HCl을 제거하기 위한 CaO를 주입을 모사 하므로써 실제 운영 적용 전 단계에 역할로 유용한 도구로 판단된다.

• Journal of Information Display
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• v.5 no.4
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• pp.12-17
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• 2004

A series of statistical random copolymers of dioctylfluorene (DOF) and 3,4-ethylenedioxythiophene (EDOT) were synthesized by Ni (0) mediated polymerization and their light-emitting properties were compared with poly (9,9-di-n-octylfluorene) (PDOF). The synthesized polymers were characterized using UV-vis spectroscopy, TGA, photoluminescence (PL) & electroluminescence (EL) spectroscopy and by conducting molecular weight studies. The resulting polymers were found to be thermally stable and readily soluble in organic solvents. The UV-visible absorption and PL emission spectra of the copolymers were gradually red-shifted as the fraction of EDOT in copolymers increased. Light-emitting devices were fabricated in an ITO (indium-tin oxide)/PEDOT/polymer/Ca/Al configuration. Interestingly, the EL spectra of these devices were similar to the PL spectra of the corresponding polymer film. However, the EL devices constructed from the copolymer showed more than 10 times higher efficiency level than the devices constructed from the PDOF homopolymer. This higher efficiency is possibly the result of better charge carrier balance in the copolymer systems due to the lower HOMO levels of the copolymers in comparison to that of PDOF homopolymer.

• Macromolecular Research
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• v.11 no.4
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• pp.283-290
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• 2003

Organic drugs including aspirin, omeprazole, and naproxen with three different levels of octanol/water partition coefficient were examined for their release behavior from the amphiphilic PCL-b-PEO-b-PCL (PCEC) matrix. Scanning electron micrograph (SEM) of PCEC illustrated a well defined two-phase morphology consisted of dispersed poly(ethylene oxide) (PEO) domain and continuous polycaprolactone (PCL) phase. Differential scanning calorimetry (DSC) and X-ray diffractometry (XRD) experiments veri tied that three model drugs are dissolved as a molecular dispersion in PCEC matrix. The release of hydrophilic aspirin closely followed the water absorption profile of the matrix indicating that its major fraction is present in PEO domain. However, substantial amount of aspirin present in less hydrophilic region displayed discontinuous biphasic release pattern. In the case of omeprazole with intermediate hydrophobicity consistent release behavior was observed for a period of 24 hrs after the rapid liberation of ca. 10% of the drug presumably partitioned in PEO phase. It was ascribed to the fact that the progressive hydration of PCEC matrix gradually increased the chance of drug/water exposure to compensate the exhaustion of device. Naproxen with the highest octanol/water distribution coefficient among three model drugs exhibited a limited release of 35% for 24 hrs. Finally, hydroxypropyl methylcellulose phthalate (HPMCP)/PCEC blend matrix demonstrated an accelerated and quantitative release of hydrophobic naproxen by generating high porosity and thereby expanding polymer/water interface.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.4
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• pp.399-406
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• 1996

Acidic fog is catastrophic to aviation and potentially affect materials, vegetation, crops and public health. This paper was carried out to investigate the chemical features of fog sample at Mt. Sobaek (mean sea level : 1, 340m) from June to August 1995. Each sample was analyzed for pH, electrical conductivity and major ions (anion : $Cl^N)_3^-, SO_4^{2-}, cation : Na^+, NH_4^+, K^+, Mg^{2+}, Ca^{2+}$) by ion chromatography. The quality analysis of fog sample data was performed based on ion balance and electrical conductivity method. The wind directions are subdivided into the northerly and southerly wind according to the wind direction data at the Sobaek-san meteorological observation station. Statistical analyses were performed on the complete set of results in order to obtain a description of fog sample. All the statistical treatment was carried out using the SPSS/PC + software package. The major ion concentration of fog samples was higher for the northwesterly wind cases than sourtheasterly wind cases. The pH of fog sample varied between 2.95 and 6.08. The average pH and electrical conductivity of total sample (n=210) were 4.39 and 113.0 $\mu$S/cm, respectively. It may be noted that in nearly all the cases, the dominant major ions in the fog sample at Mt. Sobaek were $SO_4^{2-}, NO_3^-, H^+ and NH_4^+$.

• Textile Coloration and Finishing
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• v.24 no.4
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• pp.253-259
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• 2012

In this work, the natural indigo production process from Polygonum tinctorium was balanced based on the traditional Niram method in Korea. A standard procedure was determined considering the conditions of indican extraction from plant material, the amount of alkali for precipitation, storage of extract, etc. The effect of experimental conditions on the yield of crude dye was investigated. The contents of indigo and indirubin of the crude dyes were analyzed by HPLC. Increase of the amount of crude dye was observed within 1-2.5 days of extraction time. Longer extraction beyond 2.5 days resulted in a slight decrease in the amount of crude dye. There was no consistency in terms of indigo content depending on extraction pH. We found that the storage of extract or harvested plants affected adversely to dye yield and dye quality. Based on the lab scale extraction, large scale extraction was performed for 2-2.5 days in water and 2.0-2.5 g/L of $Ca(OH)_2$ was applied for precipitation of indigo dye. We obtained natural indigo dye containing about 15% of pure indigo in scale-up production using whole plant except root.