• 대한기계학회논문집A
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• 제29권3호
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• pp.425-431
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• 2005

The efficiency of complex slurry preparation route for developing the high performance SiC matrix of $RS-SiC_{f}/SiC$ composites has been investigated. The green bodies for RS-SiC materials prior to the infiltration of molten silicon were prepared with various C/SiC complex slurries, which associated with both the sizes of starting SiC particles and the blending conditions of starting SiC and C particles. The characterization of Rs-SiC materials was examined by means of SEM, EDS and three point bending test. Based on the mechanical property-microstructure correlation, the process optimization is also discussed. The flexural strength of Rs-SiC materials greatly depended on the content of residual Si. The decrease of starting SiC particle size in the C/SiC complex slurry was effective for improving the flexural strength of RS-SiC materials.

• Journal of Ginseng Research
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• 제33권3호
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• pp.229-233
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• 2009

홍삼농축액분말을 발효주정을 이용하여 과립입자를 제조한 후 이것을 원심력에 의해 부유시키고 성장시켜 100% 홍삼농축액 환을 제조하는 새로운 원심분리 코팅방법을 개발하였다. 본 방법은 홍삼농축액을 순차적으로 분무하면서 흡입공기 온도 60$\sim$70$^{\circ}C$, 분무공기 압력 3.0$\sim$4.0 bar, 투입구 온도 20$\sim$50$^{\circ}C$, 투입속도 1$\sim$1,000 g/min, 회전판속도 1,000$\sim$1,500 rpm, 외부온도 (outlet temperature) 25$\sim$40$^{\circ}C$의 조건으로 제조하였다. 홍삼농축액환의 제조수율은 85% 이었고, 제조에 소요된 시간은 7$\sim$8 시간 이었다. 홍삼농축액환은 홍삼농축액분말에 비해 흡습성 내성이 매우 우수하였고, 비중감소에 의해 물에서의 용해시간도 1 분 이내로 우수하였다. 반면 홍삼의 활성 및 지표성분인 진세노사이드는 제조과정 중 큰 성분 분해없이 안정하였다.

• Archives of Pharmacal Research
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• 제28권5호
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• pp.619-625
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• 2005

Beads loaded with the water-soluble drug, phenylpropanolamine HCl (PPA), were prepared using an extruder and double arm counter-rotating roller modified from a traditional pill machine. The mean diameter of the cylindrical rod-like extrudate from the ram extruder was 3 mm; that of the uncoated bead after cutting and spheronization by the modified double arm counter-rotating roller was 3.26~3.28 mm. Although the surface of the beads was moderately rough and irregular, some exhibited hump-shaped protrusions, the sphericity was acceptable (roundness 1.15) and adequate for the subsequent coating process. An increase in mean diameter of the coated beads and improvements in friability and sphericity were observed in proportion to the amount of coating material applied (ethylcellulose or Eudragit？？ RS 100). It was also found that the release rate of PPA from the coated beads could be controlled by the amount and type of coating materials applied or with the incorporation of Eudragit ？？ RS 100 into the core matrix. Further modifications to the double arm counter-rotating roller, including adjustment of the rotation speed and distance between the rollers, would yield smaller uncoated beads with improved roundness and surface roughness. In conclusion , the present method could be potentially applied to prepare controlled release drug delivery beads or pellet dosage forms.

• 한방안이비인후피부과학회지
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• 제29권4호
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• pp.114-130
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• 2016

Objectives : This study is performed to investigate the therapy on tinnitus through the literature of Eastern and Western medicine. Methods : This study review the definition, etiology, classification, internal and external methods of treatment of tinnitus based on 50 articles of Eastern medicine, 16 articles of Western medicine about the treatment of tinnitus. Results : The results were as follows. 1. In Eastern medicine, the cause and mechanism of disease of tinnitus arose from the state of qi-blood deficiency, internal dampness-heat and depression stagnation. In Western medicine, there are mainly caused by damage to the auditory system the lower induced changes in the upper. 2. In Eastern medicine, differentiation of syndromes classifies clinical aspects, and cause and mechanism of disease. In Western medicine, it divides into an generating region, clinical and associated symptoms aspects. 3. In Eastern medicine, internal method of treatments of tinnitus are divided into four treatments. In Western medicine, internal methods of tinnitus are vasodilators, blood-flow improvers, Metabolism improvers etc. 4. In Eastern medicine, external method of treatments of tinnitus are paste preparation method, powder preparation method, pill preparation method, acupuncture & moxibustion method. In Western medicine, external method of treatments of Tinnitus are divided into injection, other surgical therapies and adjuvant therapy. Conclusions : Until now, there is no perfect, effective single treatment. We think that Eastern medicine approach and treatment can be helpful to overcome the limitations of tinnitus cure.

• Journal of the Korean Wood Science and Technology
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• 제15권3호
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• pp.34-43
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• 1987

This study was performed to find out the types of linkage of carbohydrates in wood cell walls. To study the structure of linkage of carbohydrates in wood cell walls, we have attempted to find out the method holocellulose preparation and optimum condition of enzyme hydrolysis in holocellulose, and fractionate oligosaccharide with products that hydrolized partly by acetolysis and deacetylation in holocellulose. We have achieved four results. These results as follow; 1. At first. we reacted in wood meal $NaClO_2$ 1g per lignin lg for one hour and then the same of quantity $NaClO_2$ for four hours. Through these experiments, we have developed new holocellulose preparation method which had low loss of carbohydrates and high effect of the delignification. 2. The optimum condition of enzyme hydrolysis of holocellulose which had lignin was 0.005M sodium acetate buffer (pH 5.0). We have achieved 7.2% reducing sugar through the procedure that reactioned 0.01g holocellulose putting enzyme 0.03g for 72 hours. It may be supposed that 5.5% of lignin contained in holocellulose prevented enzyme contaction from holocellulose and so this lignin has resulted in the low efficiency of enzyme hydrolysis. 3. We did not fractionated from oligosaccharides which were preparated by the method of acetolysis and deacetylation in holocellulose. The reason is that holocellulose having a lot of lignin prevented prefectly partial hydrolysis from the method of acetolysis and deacetylation. 4. We attempted analysis of six standard substances through HPLC apparatus having sugar pak 1 column which we have changed flow rate and the column temperature variably. These six standard substances were D-glucose, D-mannose, D-xylose, D-galactose and L-rhamnose, L-arabinose, But sugar pak 1 column was not fitted analysis of four substances because D-galactose, D-mannose, D-xylose, L-rhamnose were agreement with elution time. And so, we could not analize four standard substances with sugar pak 1 column.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.380-385
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• 2004

The efficiency of complex slurry preparation route for developing the high performance SiC matrix of RS-SiCf/SiC composites has been investigated. The green bodies for RS-SiC materials prior to the infiltration of nw/ten silicon were prepared with various C/SiC complex matrix slurries, which associated with both different sizes of starting SiC particles and blending ratios of starting SiC and carbon particles. The characterization of RS-SiC materials was examined by means of SEM, TEM, EDS and three point bending test. Based on the mechanical property-microstructure correlation, process optimization methodology is also discussed. The flexural strength of RS-SiC materials greatly depended on the content of residual Si. The decrease of starting SiC particle size in the C/SiC complex slurry was effective for improving the flexural strength of RS-SiC materials.

• Bulletin of the Korean Chemical Society
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• 제34권9호
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• pp.2657-2662
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• 2013

Multiwalled carbon nanotube (MWCNT)-g-poly (aniline-co-2,5-diaminobenzenesulfonic acid) (DABSA) reinforced Nafion$^{(R)}$ nanocomposite membranes were prepared and characterized for direct methanol fuel cells (DMFCs). The nanocomposite membranes with approximately $90{\mu}m$ thickness were prepared by the water assisted solution casting method. To evaluate the properties of nanocomposite membranes for DMFC applications, the nanocomposite membranes were characterized by methanol and water uptake, thermal stability, and ion exchange capacity (IEC). Furthermore, oxidative stability measurements in terms of the hydrogen peroxide decomposition rate that represent the oxidative stability of the membranes were examined. The methanol uptake values of the nanocomposite membranes were dramatically decreased compared to the cast Nafion$^{(R)}$ membranes. The IEC values of the nanocomposite membranes were increased about 30% compared to the cast Nafion$^{(R)}$ membrane.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.165-166
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• 2008

$(Ba_{0.6},Sr_{0.3},Ca_{0.1})TiO_3$ powders, which were prepared by sol-gel method using a solution of Ba-acetate, Sr-acetate and Ca-acetate and Ti iso-propoxide, were mixed with organic vehicle and the BSCT thick films were fabricated by the screen-printing techniques on high purity alumina substrates. The structural and dielectirc properties were investigated for various $Pr_2O_3$ and $Y_2O_3$doping contents. As a result of thermal analysis of $(Ba_{0.6},Sr_{0.3},Ca_{0.1})TiO_3$ powders, the exothermic peak was observed at around $670^{\circ}C$ due to the formation of the polycrystalline perovskite phase. All BSCT thick films, sintered at $1420^{\circ}C$ for 2h, showed the typical XRD patterns of perovskite polycrystalline structure. The average grain size of the specimens decreased with amount of $Pr_2O_3$ and $Y_2O_3$ contents.

• Journal of Biosystems Engineering
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• 제32권1호
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• pp.50-56
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• 2007

Highly porous composite bioceramic bone scaffolds were developed using sintered gnotobiotic pig bones. These scaffolds consisted of poly-D,L-lactic acid (P(D,L)LA) and bioceramic materials of pig bone powder. The bone scaffolds were able to promote biocompatibility and possess interconnected pores that would support cell adhesion and proliferation adequately. The composite scaffolds were tested with dental pulp stem cells for cytotoxicity test. Cells seeded on the composite scaffolds were readily attached, well proliferated, as confirmed by cytotoxicity test, and cell adhesion assessment. The composite bone scaffold had no toxicity in cytotoxicity test on the extract of 0.013 g scaffold to 2 ml culture medium. The cells on the composite bone scaffold proliferated better than cells on the P(D,L)LA scaffolds.

• 생약학회지
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• 제40권2호
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• pp.155-160
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• 2009

The reference herbal extracts and their identification methods by Korean Pharmacopoeia IX were established based on the organic solvent extracts to detect their marker compounds. However, most of herbal medicine decoctions in the market are prepared with water as extracting solvent. As the reference herbal extracts and their identification methods are not appropriate for the practical test, new preparation of alternative reference herbal extracts and their identification test methods are essential for the correction of test methods and identification of herbal drugs. Three novel identification test methods were developed for Evodiae Fructus, Cimicifugae Rhizoma and Aurantii Fructus Immaturus. Total 10 reference herbal extracts and their identification methods were optimized for Ephedrae Herba, Schisandrae Fructus, Curcuma longae Rhizoma, Citri Unshius Pericarpium, Puerariae Radix, Corni Fructus, and Cinnamomi Cortex.