• Journal of the Korean institute of surface engineering
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• v.20 no.4
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• pp.135-143
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• 1987

Various complexing agents were investigated to see the effects on the normal orientation of HCP structure of Co-alloy to the film plane in ammoniacal electroless plating bath. To obtain the optimum condition, several complexing agents were investigated to compare the C-axis perpendicular orientation. Results were that succinate - citrate, malonate - succinate, malonate bath were useful for that purpose. Among these complexing agents, succinate - citrate system was obtained as the best one. X-ray diffraction patterns were used to compare the film properties with C-axis perpendicular orientation.

• Tuberculosis and Respiratory Diseases
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• v.41 no.5
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• pp.568-573
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• 1994

Corticosteroids are widely used in the treatment of various diseases because of its potent antiinflammatory effect. According to recent knowledge, bronchial asthma is also chronic inflammatory disease. Therefore antiinflammtory agent such as cromoyln sodium and corticosteroid is highly recommended for treament of chronic bronchial asthma. Especially hydrocortisone succinate (Solu-Cortef) is commonly used for treament to acute asthmatic attack via intravenous injection due to have rapid therapeutic onset and short duration. Since Sunaga et al. reported acute asthma attack after hydrocortisone injection in 1973, several cases of bronchospam with or without angioedema and urticaria after intravenous injection of hydrocortisone have been reported. We experienced a case of severe bronchospasm and acute respiratory failure after intraveous injection of hydrocortisone succinate in 64 year-old female asthmatic patient who visited to emergency room for acute asthmatic attack. About 5 minites after Solu-Cortef injection, a severe bronchospasm with arterial hypoxemia was developed. In order to confirm the suspected relationship between the offending drug(Solu-Cortef) and acute bronchospasm, we examed intravenous and inhalation provocation test by hydrocortisone succinate and methylprednisolone(control). After administration of hydrocortisone succinate via intravenous and inhalation route, severe asthmatic attack occurred. But administration of intravenous methylprednisolone and orall triamcinolone and saline were not provoke bronchospasm. Skin test using hydrocortisone sodium succinate was also positive. Administration of hydrocortisone is very serious to asthmatic patient with hydrocortisone hypersensitivity. Therefore, the clinician must be have history taking about previous adverse reaction of steroid before its clinical use. And methylprednisone may be useful and safe drug to the treatment of acute asthmatic patient with hydrocortisone hypersensitivity.

• Polymer(Korea)
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• v.25 no.4
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• pp.486-495
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• 2001

Degradable poly(butylene succinate) (PBS)/poly(TEX>${\varepsilon}$-caprolactone) (PCL) copolyesters were prepared by using transesterification between poly(butylene succinate) and poly(TEX>${\varepsilon}$-caprolactone). The thermal and mechanical properties of copolyesters were investigated using differential scanning calorimetry and tensile testing. Interchange reaction between PBS and PCL molecules could be identified from proton NMR spectra. The reduced viscosity of the PBS/PCL copolyesters increased with reaction time except for a series of PBS/PCL (50/50 wt%) copolyesters. For all the compositions, the melting point and crystallization temperature of high-$T_m$ component (PBS) decreased as reaction time increased. From the results of tensile testing, it was found that stress and strain at break of the PBS/PCL copolymers containing less than 40 wt% PCL improved as compared to those of pure PBS, but at 50 wt% PCL stress at break of PBS/PCL copolymers was lowered due to decrease of crystallinity. On the other hand, Young's moduli of all the copolyesters decreased with both reaction time and PCL content.

• Proceedings of the Korean Fiber Society Conference
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• 2007.11a
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• pp.463-464
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• 2007

See Full Text

• Proceedings of the Korean Fiber Society Conference
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• 1998.04a
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• pp.91-96
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• 1998

본 연구에서는 환경분해성 aliphatic polyester인 Poly(tetra- methylene succinate) (이하 PTMS)의 형태학적 고찰을 통한 분해성과 구조와의 관계를 고찰하였다. 과거, 분해성 고분자는 의료용으로서 학문적인 관심의 대상이었으나, 고분자에 의한 환경 오염문제가 대두됨에 따라 산업용 고분자의 분해성에 관한 연구가 많이 진행되었다. 고분자의 분해성은 분해환경 뿐만 아니라, 고분자 사슬의 화학구조, morphology, 미결정의 크기, 분자량, 분자량 분포 등에 의해 영향을 받는 것으로 보고되었다.(중략)

• Journal of the Korean institute of surface engineering
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• v.19 no.2
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• pp.44-50
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• 1986

Effects of cathodic overvoltages on the electrodeposition of lead from electrolyte containing lead chloride, ammonium acetate and sodium succinate was investigated at 20$^{\circ}C$. The use of organic additives, phenol and gelatin was found effective to inhibit the growth of dendritic crystals. At the carthodic overvoltages higher than 0.2V, the lead deposit becames less compact even in the presence of organic additives. The applications of agitation and pulse current promoted compact and shiny deposits.

• Polymer(Korea)
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• v.29 no.6
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• pp.557-564
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• 2005

Thermoplastic starch (TPS) was manufactured and blended with poly(butylene adipate-co-succinate) (PBAS), which is one of the most popular biodegradable aliphatic polyesters. The effects of the TPS contents on the mechanical properties, thermal characteristics, and biodegradability of PBAS/TPS blends were investigated. The foaming characteristics of those were also studied. With small amount of TPS, mechanical properties of the blends were largely deteriorated and the variations of them decreased with more addition of TPS. In addition, TPS decreased crystallinity and thermal decomposition temperature of PBAS. The PBAS/TPS foam having maximum blowing ratio was obtained with 20 Phr of TPS, and their blowing ratio decreased with the further increase of TPS.

• The Journal of the Korean Society for Microbiology
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• v.20 no.1
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• pp.55-63
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• 1985

Phosphate, ammonia, glucosamine, glucose, pyruvate, succinate, fumarate, malate and acetate were examined for their ability to control the heat-stable enterotoxin (ST) production in succinate salts medium or in M9 medium. The results obtained were summerized as follows. 1. When the initial phosphate concentration was adjusted to 1.0mM, ST production was decreased to 80u/ml or less. But when the initial phosphate concentration was adjusted to 64mM or 100mM, enterotoxin production was 320u/ml. 2. When the initial ammonia concentration in the medium was adjusted to 1.0mM, no ST production and cell growth were observed. But when ammonia concentration was adjusted to 10mM, 19mM, 38mM or 76mM, enterotoxin production was 320u/ml. 3. Among carbon sources, glucosamine, glucose, pyruvate, succinate, fumarate, malate and acetate, acetate supported the highest specific production (928 unit/O.D.) of heat-stable enterotoxin. From this results, we could assume that heat-stable enterotoxin production is controlled by stringent control mechanism. 4. When the pH of the succinate salts medium was kept between 6.2 to 6.5, no heat-stable enterotoxin production was observed, but when the pH of the medium was kept between pH 6.2 to 6.5, 267 unit/O.D. of heat-stable enterotoxin was produced. 5. Glucose inhibited the heat-stable enterotoxin production and the mechanism was assumed due to its capacity to lower the pH of the medium during catabolysis and its high metabolic energy.

• Microbiology and Biotechnology Letters
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• v.48 no.1
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• pp.90-97
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• 2020

Vinegar was prepared from corn produced in Gangwon province and changes to the major aroma components were investigated for acetic acid fermentation and ripening. The most prevalent volatile component in corn alcohol was determined to be 2-phenylethanol (accounting for 27% of total aroma components); the levels of 2-phenylethanol decreased to 15% after acetic acid fermentation. Principal component analysis of volatile compounds revealed that corn vinegar was distinguishable from corn alcohol. The highest content of total volatile components (50%) was acetic acid, followed by 2-phenylethanol and diethyl succinate. Ethyl phenylacetate and diethyl succinate had the highest odor activity value, and might contribute most profoundly to the aroma of corn vinegar.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.4
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• pp.451-457
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• 2011

Purple non-sulfur (PNS) bacterium $Rhodobacter$ $sphaeroides$ KD131 was studied with the aim of achieving maximum hydrogen production using various carbon and nitrogen sources at different pH conditions. Cells grew well and produced hydrogen using $(NH_4){_2}SO_4$ or glutamate as a nitrogen source in combination with a carbon substrate, succinate or malate. During 48h of photo-heterotrophic fermentation under 110$W/m^2$ illumination using a halogen lamp at $30^{\circ}C$, 67% of 30mM succinate added was degraded and the hydrogen yield was estimated as 3.29mol $H^2$/mol-succinate. However, less than 30% of formate was consumed and hydrogen was not produced due to a lack of genes coding for the formate-hydrogen lyase complex of strain KD131. Initial cell concentrations of more than 0.6g dry cell weight/L-culture broth were not favorable for hydrogen evolution by cell aggregation, thus leading to substrate and light unavailability. In a modified Sistrom's medium containing 30mM succinate with a carbon to nitrogen ratio of 12.85 (w/w), glutamate produced 1.40-fold more hydrogen compared to ammonium sulfate during the first 48h. However, ammonium sulfate was 1.78-fold more effective for extended cultivation of 96h. An initial pH range from 6.0 to 9.0 influenced cell growth and hydrogen production, and maintenance of pH 7.5 during photofermentation led to the increased hydrogen yield.