• Applied Biological Chemistry
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• 제23권3호
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• pp.166-172
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• 1980

광학 현미경 및 Scanning electron microscopy로 관찰한 녹두 전분 입자는 타원형 및 구형으로서 너비는 $8{\sim}13{\mu}m$, 길이는 $18{\sim}30{\mu}$이었다. X-ray 회절도는 $2{\theta}$가 $16.9^{\circ}$에서 약간의 결정성을 보였다. 전분의 blue value는 0.36, 아밀로스 함량은 22.7%, 알카리 수는 8.52, ferricyanide 수는 1.06물 결함 능력은 81.6%이었다. 전분의 팽윤은 $50^{\circ}C$까지는 큰 변화가 없었고, 이후 급격히 증가하였다. 전분 현탁액(0.3%)의 광 투과도는 $65^{\circ}C$ 이후 급격히 증가하였으며, $65{\sim}90^{\circ}C$에서는 Single stage의 호화 양상을 보였다. 아밀로그래프에 의한 전분의 호화는 농도(건물중으로 6,7 및 8%)에 관계없이 최고 점도는 나타나지 않았다. 전분 gel(건물중으로 40% 농도)의 retrogradation시 시간상수는 $21^{\circ}C$에서 1.99일이었다.

• Korean Chemical Engineering Research
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• 제53권6호
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• pp.762-769
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• 2015

직경 2~3 nm 크기를 갖는 이산화티탄 나노입자가 산성 용액에서 titanium tetraisopropoxide(TTIP)의 가수분해 반응을 조절함에 의해 합성되었다. 생성된 이산화티탄 나노입자를 졸-겔법에 의해 3-glycidoxypropyl trimethoxysilane(GPTMS)과 반응시킴에 의해 유-무기 혼성 코팅 용액이 제조되었다. 그 후 코팅 용액을 기재인 polycarbonate(PC) 시트 위에 스핀 코팅시키고, $120^{\circ}C$에서 열경화 시켜 고굴절률 하드코팅 도막이 제조되었다. 코팅 도막은 가시광선 영역에서 90%의 높은 광학적 투과율을 보였으며 2H의 연필경도를 나타내었다. 또한 코팅 용액 내의 이산화티탄 나노입자의 함량이 4%에서 25%로 증가됨에 따라 코팅 필름의 굴절률은 633 nm 파장에서 1.502로부터 1.584로 향상되었다.

• 약학회지
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• 제49권4호
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• pp.323-329
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• 2005

Antimicrobial peptides are evolutionary ancient weapons for animal and plant species to depend themselves against infectious microbes. In the present study, we investigated if an antimicrobial peptide was produced from Coptidis Rhizoma. For the determination, protein substance from the medicinal plant was isolated by various preparations. Among the preparations, the protein portion dissolved in phosphate-buffered saline solution (CRP-DS) that contained the most amount of protein $(90\%)$ resulted in maximal inhibition of Candida albicans which causes local and systemic infections. Analyses by gel-electrophoresis and gel-permeation chromatography showed the CRP-DS formed a single band of approximately 11.8 KDa as molecular size. Antifungal activity of the CRP-DS was almost equivalent to antifungal activity by fluconazole, resulting in MIC (minimal inhibitory concentration) of approximately $50{\mu}g/ml$. The antifungal activity was a dose-dependent. The antifungal activity appeared to be inactivated by heat-treatment and ionic strength, respectively. In a murine model, the CRP-DS enhanced resistance of mice against disseminated candidiasis. The HPLC analysis demonstrated maximum $4\%$ of berberine as residual content in the CRP-DS preparation resulted in no influence on the antifungal activity. In addition, protein portion isolated from Phellodendri Cortex producing the alkaloid component like Coptidis Rhizoma had no such anticandidal effect. These results indicate that the protein substance from Coptidis Rhizoma was responsible for the antifungal activity.

• 한국재료학회지
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• 제29권12호
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• pp.741-746
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• 2019

New triple tungstate phosphors NaPbLa(WO₄)₃:Yb³⁺/Ho³⁺ (x = Yb³⁺/Ho³⁺ = 7, 8, 9, 10) are successfully fabricated by microwave assisted sol-gel synthesis and their structural and frequency upconversion (UC) characteristics are investigated. The compounds crystallized in the tetragonal space group I4₁/a and the NaPbLa(WO₄)₃ host have unit cell parameters a = 5.3927(1) and c = 11.7961(3) Å, V = 343.05(2) ų, Z = 4. Under excitation at 980 nm, the phosphors have yellowish green emissions, which are derived from the intense ⁵S₂/⁵F₄→⁵I₈ transitions of Ho³⁺ ions in the green spectral range and strong ⁵F₅→⁵I₈ transitions in the red spectral range. The optimal Yb³⁺:Ho³⁺ ratio is revealed to be x = 9, which is attributed to the quenching effect of Ho³⁺ ions, as indicated by the composition dependence. The UC characteristics are evaluated in detail under consideration of the pump power dependence and Commission Internationale de L'Eclairage chromaticity. The spectroscopic features of Raman spectra are discussed in terms of the superposition of Ho³⁺ luminescence and vibrational lines. The possibility of controlling the spectral distribution of UC luminescence by the chemical content of tungstate hosts is demonstrated.

• 한국약용작물학회지
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• 제2권2호
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• pp.168-173
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• 1994

배초향의 지상부로 부터 수증기 증류법에 의해 정유성분을 분리한 다음 silica gel column chromatography에 의해 탄화수소화합물 분획과 함산소화합물 분확으로 나눈후 GC 및 GC-MS에 의해 각 분획의 성분조성을 분석한 결과는 다음과 같다. 1. 배초향의 정유함량은 건물증량으로 잎에서는 0.29%, 꽃에서는 0.38%였으나 줄기에서는 전혀 검출되지 않았다. 2. 잎의 정유에서 분리한 탄화수소화합물 분획에서 확인된 13종의 성분중 주성분은 ${\beta}-caryophyllene(59.3%)$, limonene(13.1%), ${\delta}adinene$ (10.7%) 이었고, 함산소화합물 분획에서 확인된 44종의 성분중 주성분은 methyl chavicol(79.1%), cis-3-(l-propenyl)phenol(4.5%) 등이었다. 3. 잎과 꽃의 정유성분 조성에서 양적으로 가장 많이 함유된 성분은 methylchavicol 이었고, limonene, trans-2-hexenal, 1-octen-3-one, 6,10,14-trimethylpentadecan-2-one 및 phytol등은 잎에서 특징적으로 검출된 반면 jasmone 및 p-methoxyacetophenone등은 양적으로 미량이지만 꽃에서 많이 검출되었다.

• 한국세라믹학회지
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• 제31권10호
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• pp.1147-1158
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• 1994

From Zr(O-nC3H7)4-H2O-C2H5OH-HNO3 starting solutions, MgO-doped stabilized zirconia fibers with varying content of MgO (10~18 mol%) from different MgO sources were fabricated by sol-gel method. The MgO sources used are magnesium nitrate hexahydrate, magnesium acetate tetrahydrate, and magnesium ethylate. The phase transformation studies of a drawn MgO-ZrO2 fiber were carried out using X-ray diffraction, IR spectroscopy, and Raman spectroscopy. The microstructure, tensile strength, and microporosity of fibers were investigated using SEM, tensile strength test, and microporosimeter. Although various MgO sources such as magnesium nitrate, acetate, and ethylate were used, the crystallization behavior of MgO-ZrO2 fibers at different temperatures could be summarized as follows: CubiclongrightarrowMetastable TetragonallongrightarrowMonocliniclongrightarrowCoexistence of Monoclinic and CubiclongrightarrowCubic(trace of monoclinic). At 150$0^{\circ}C$, the phase transformation of MgO-ZrO2 fibers shows the following change depending on the amount of MgO[Mg(NO3)2.6H2O]: At 10 mol%, both monoclinic and cubic phase coexist, at 12 mol%, monoclinic phase decreases rapidly, and then at 14 mol%, only cubic phase remains. When the MgO-ZrO2 fibers containing 12 mol% magnesium nitrate were heated at 80$0^{\circ}C$ for 1hr, average tensile strength of fibers is 4.0 GPa at diameters of 20 to 30 ${\mu}{\textrm}{m}$. As the heat-treatment temperatures increase to 100$0^{\circ}C$ for 1 hr, tensile strength of MgO-ZrO2 fibers decreases rapidly to 0.7 GPa.

• 한국식품영양과학회지
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• 제18권2호
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• pp.195-198
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• 1989

도축장에서는 폐기되는 돼지 혈액으로부터 혈장을 분리하여, pH, 온도, 단백질함량에 따른 혈장 단백질 보수력의 변화를 조사하였다. 돼지 혈액으로부터 혈장분리는 1400g-force에서 가장 좋았다. 단백질 농도가 5%인 혈장액을 $85^{\circ}C$에서 30분간 가열하였을 때 pH가 증가함에 따라 혈장단백질보수력은 급격히 증가하다가 pH 7 이후에는 완만한 증가를 나타냈다. 단백질 농도가 5%이고 pH 7인 혈장액에서의 보수력은 gel화 온도가 높을수록 짧은 시간 내에 높은 보수력을 나타냈으며 가열 초기에 급격히 증가하다가 일정 가열 시간 이후에는 큰 변화를 나타내지 않았다. pH가 7인 혈장액을 $85^{\circ}C$에서 30분간 가열하였을 때 혈장 단백질의 농도가 증가함에 따라 단위 단백질 무게당 보수력은 감소하였다.

• 약학회지
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• 제36권3호
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• pp.212-219
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• 1992

Although oral route is the most convenient route for drug administration, the short and variable transit of drug through GI tract restricts the sustained drug absorption after oral administration. Thus, for sustained absorption of drugs, it is desirable to prolong the GI transit time by retaining the dosage forms in the stomach. In this study, the enzyme-digestible swelling hydrogel was synthesized by heating the mixed solution of N-vinyl-2-pyrrolidone[monomer], acrylated albumin[crosslinking agent] and proxyphylline[drug] at $65^{\circ}C$ for 10 hours in the cylindrical test tube. The resultant hydrogel tablet (diameter; 0.77 cm, thickness; 0.47 cm) was designed to swell in the gastric fluid after oral administration to such a size that passing through the pylorus could be inhibited during the drug release. After releasing drug, the hydrogel was expected to be degraded by pepsin, an enzyme in the stomach, and eventually solubilized. Actually, the hydrogel synthesized in the study swelled to a size larger than the diameter of the pylorus ($1.3{\pm}0.7$ cm) and slowly digested in the presence of pepsin. Drug release from the hydrogel was prolonged up to about 12 hours. The swelling kinetics was dependent on albumin acrylation time, drug content and gel thickness. Particularly the gel thickness was the most important factor that influences on drug release. By adjusting these factors, the albumin-crosslinked hydrogel was expected to be retained in the stomach for up to 60 hours and used as a potential platform of drugs for long-term GI absorption.

• 공업화학
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• 제28권6호
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• pp.626-631
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• 2017

투명 플라스틱 소재를 광학용으로 적용하기 위해서는 표면경도 및 내열성과 같은 물성의 개선이 필요하다. 본 연구에서는 이러한 물성의 개선을 위하여 자외선 경화형 유기/무기 하이브리드를 합성하였다. 유기소재 안에 무기 성분이 균일하게 최적상태로 분산되도록 하기 위하여 졸-겔 반응을 기초로 하여 동시에 반응이 진행되도록 하였다. 이러한 졸-겔 반응과 빠른 자외선 경화반응을 적절히 조합하여 우레탄 아크릴레이트 유기소재 안에 무기 성분의 분산성이 향상되도록 하여 투명성이 우수한 코팅층을 형성시킬 수 있었다. 자외선 경화형 유기/무기 하이브리드의 경화도와 코팅 물성을 변화시키기 위하여 다양한 종류의 알콕시 실란을 사용하였다. 이러한 자외선 경화형 유기/무기 하이브리드 코팅에서의 무기 성분의 함량에 따라 표면 경도와 내열성을 조절할 수 있었다.

• Archives of Plastic Surgery
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• 제33권2호
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• pp.198-204
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• 2006

Many clinical trials have shown the effectiveness of the platelet releasate or the platelet gel on chronic wounds. However, the patient's own blood had to be aspirated and processed to make the platelet releasate or a platelet gel. The purpose of this study was to assess the effects of platelet concentrates from the blood bank for the treatment of diabetic foot ulcers. To obtain the basic data of the PDGF-BB content in platelet concentrates supplied from the blood bank, enzyme-linked immunosorbent assay quantification was performed. On average, 8.5 pg of the PDGF-BB was released per 1 million platelets. Sixteen patients with diabetic foot ulcers ranging from 1.0 to $18.0cm^2$(mean, $6.1cm^2$) in size were treated. The platelet concentrates was centrifuged and the precipitantte was mixed with 1 ml of fibrinogen. The platelets and fibrinogen mixture was dispersed on to the ulcer lesions. The liquid platelet and fibrinogen mixture was then sealed using 0.3-1.0 ml of thrombin and moisture dressing was performed. The procedure was repeated every one or two weeks until wound closure. Time required for complete healing ranged from 3 to 12 weeks after treatment (mean, 7.3 weeks). Patient satisfaction was also very positive. In this study, the use of platelet concentrates from the blood bank was found to be effective in treating diabetic foot ulcers.