• 대한미생물학회지
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• 제11권1호
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• pp.1-11
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• 1976

Escherichia coli(ATCC 11115)에 실험실등에서 상용하는 여러가지 항균제를 시간별로 처리, 그 변화양상을 전자현미경으로 관찰한 바 그 결과를 요약하면 다음과 같다. 1) 대조군은 3층의 단일막으로 형성된 세포벽에 둘러쌓여 있으며 세포질은 전자밀도가 낮은 nucleoid와 ribosme들이 산재하여 있음을 관찰할 수 있었다. 2) 70% ethanol용액 처리군은 핵물질을 관찰할 수 없었고 세포질은 세포 중앙부로 응집되어 있었으며 세포벽의 외부에서는 bleb 들을 관찰 할 수 있었다. 3) 3% $H_2O_2$ 용액 처리군은 세포내용물의 변화는 70% ethanol 처리군과 대동소이(大同小異)하였으나 세포벽에서는 심한 굴곡현상이 관찰되었다. 4) 5% lysol 용액처리군은 세포질 및 핵물질 부위가 완전히 구분되어 나타났으며 세포질내의 ribosome과립들은 시간이 경과할수록 그 응집현상이 심하였고 세포 외부에는 ribosome 양 과립들이 부착하고 있음이 관찰되었다. 5) 1% DDEGH 용액 처리군은 세포질의 응집 및 세포막과 세포벽이 뚜렷이 관찰되지 않았으며 세포외부에 세포내용물과 동일한 물질로 생각되는 물질이 부착되어 있음을 관찰할 수 있었다. 6) 고압멸균 처리군은 세포막 및 세포벽의 파괴, 탈락 및 세포내용물의 유출현상이 관찰되었다.

• 동의생리병리학회지
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• 제22권4호
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• pp.810-814
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• 2008

Most inflammatory disorders are usually treated using anti-inflammatory drugs including non-steroidal anti-inflammatory drugs (NSAID) and steroidal anti-inflammatory drugs (SAID). Prolonged uses of NSAIDs and SAIDs may frequently cause adverse side-effects such as nausea, vomiting, diarrhea, constipation, decreased appetite, kidney and liver failure, ulcers, and prolonged bleeding after an injury or surgery. Thus, it is necessarily required to develop a new anti-inflammatory drug with little side-effects. Dandelion (Taraxacum officinale) possesses the therapeutic abilities to eliminate body heat and toxins and to remove swelling and inflammation. In order to verify the anti-inflammatory activity of dandelion, TPA(12-O-tetra decanoylphorbol-acetate)-induced or croton oil-induced acute edema was developed in the mouse ears, and dandelion extract dissolved in acetone was applied to both sides of inflamed ears. It was found that dandelion could significantly reduce the ear swelling, compared to that of non-treated control. In the case of $20{\mu}{\ell}$ application of $100mg/m{\ell}$ dandelion solution (DA-100), its anti-inflammatory effect was comparable to that of indomethacin, a non - steroidal anti-anflammatory drug. Taken together, it could be concluded that topically applied dandelion extract exhibited its potentials as a new drug candidate with an effective anti-inflammatory activity.

• 분석과학
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• 제30권2호
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• pp.57-67
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• 2017

This study was conducted to develop an analytical technique for determination of chlorite and chlorate concentrations in fresh-cut food and dried fish products by an ion chromatography/conductivity detection method using a hydroxide mobile phase. Deionized water was added to homogenized samples, which were then extracted by ultrasound extraction and centrifuged at high speed (8,500 rpm). Subsequently, a Sep-Pak tC18 cartridge was used to purify the supernatant. Chlorite and chlorate ions were separated using 20 mM KOH solution as the mobile phase and Dionex IonPac AS27 column as the stationary phase. Ethylenediamine was used as sample preservative and dibromoacetate was added to adjust for the disparity in extraction efficiencies between the food samples. The method detection limit) for chlorite and chlorate were estimated to be 0.2 mg/kg and 0.1 mg/kg, respectively, and the coefficient of determination ($r^2$) that denotes the linearity of their calibration curves were correspondingly measured to be 0.9973 and 0.9987. The recovery rate for each ion was 92.1 % and 96.3 %, with relative standard deviations of 7.47 % and 6.18 %, respectively. Although neither chlorite nor chlorate was detected in the food samples, the analytical technique developed in this study may potentially be used in the analysis of disinfected food products.

• 디자인학연구
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• 제20권1호
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• pp.133-142
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• 2007

입출력 체계가 텍스트를 기반으로 이루어진 문자에 의한 커뮤니케이션은 비언어적 요소가 삭제되어 사회적 실재감이 감소하는 한계성을 지닌다. 사람들은 이를 극복하기 위해 이모티콘, 아이콘, 통신언어 등의 다양한 요소를 통해 사용자의 감정 및 상황을 시각화하는 방안을 모색하고 있다. 본 연구는 휴대폰에서의 문자 활용을 통해 글꼴을 통한 감정의 시각화 방안을 알아보기 위한 사전 연구로 문헌 연구를 통해 변화된 커뮤니케이션 환경 및 휴대폰 문자메시지 서비스, 그리고 모바일 글꼴 개발 현황에 대해 연구하고, 조사 연구를 통해 휴대폰 문자 메시지와 비언어적 커뮤니케이션에 대한 사용자 인식을 조사하였다. 이를 통해 사용자의 휴대폰 문자메세지에 대한 인식 및 글꼴을 통한 감정 표현의 가능성을 확인하였다. 본 연구를 통해 도출된 결과를 토대로 향후 휴대폰 문자메시지에서 글꼴은 감정을 시각화할 수 있는 방안을 적극적으로 모색해 볼 수 있을 것이다.

• 한국식품과학회지
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• 제10권2호
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• pp.162-172
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• 1978

탈지(脫脂) 유채박중(油菜粕中)에는 필수(必須) 아미노산(酸)이 다수함유(多數含有)한 양질(良質)의 단백질(蛋白質)을 함유(含有)하고 있으나 독소(毒素)인 myrosinase이 활성(活性)을 억제(抑制)시키거나 효소(酵素) 가수분해물(加水分解物)인 isothiocyanate 및 oxazoolidinethione을 제거(除去)하여야 한다. 이와 같은 독소(毒素)를 myrosinase 활성(活性)을 감소(減少)시키는 방법(方法)으로 처리하여 전연무독(全然無毒)한 단백질(蛋白質)을 분리(分離)하였다. 즉(卽) pH11.0에서 냉시(冷時)에 추출(抽出)하고 $0^{\circ}C$에서 침전(沈澱)을 분리(分離)하였으며 식품화학적(食品化學的)인 성질(性質) 비교(比較)를 하였다. 유채단백질(油菜蛋白質)은 분자수(分子數)가 많아 침전시(沈澱時)에는 조제(助劑)인 혹(或)은 알긴 산(酸)소 다- 를 이용(利用)하여 좋은 결과(結果)를 얻었다. 또 pH 6.7, 5.6 및 5.0에 따라 색상(色相)을 단리하는 단백질(蛋白質)이 분리(分離)되었고 수세(水洗)와 acetone을 사용(使用)하여 색소(色素)를 제거(除去)시킬 수 있었으며 냉동건조(冷凍乾燥)하여 변색(變色)을 방지(防止)하였다. 역류(逆流) 추출법(抽出法)은 양산(量産)할 수 있는 단백질(蛋白質) 추출(抽出) 방법(方法)이다.

• The Korean Journal of Physiology and Pharmacology
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• 제4권3호
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• pp.227-234
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• 2000

Many reports suggest that neurotensin (NT) in the gastrointestinal tract may play a possible role as a neurotransmitter, a circulating hormone, or a modulator of motor activity. NT exerts various actions in the intestine; it produces contractile and relaxant responses in intestinal smooth muscle. This study was designed to investigate the effect of NT on motility of antral circular muscle strips in guinea-pig stomach. To assess the role of $Ca^{2+}$ influx in underlying mechanism, slow waves were simultaneously recorded with spontaneous contractions using conventional intracellular microelectrode technique. At the concentration of $10^{-7}$ M, where NT showed maximum response, NT enhanced the magnitude $(863{\pm}198%,\;mean\;SEM,\;n=13)$ and the frequency $(154{\pm}10.3%,\;n=11)$ of spontaneous contractions. NT evoked a slight hyperpolarization of membrane potential, tall and steep slow waves with abortive spikes $(278{\pm}50%,\;n=4).$ These effects were not affected by atropine $(2\;{\mu}M),$ guanethidine $(2\;{\mu}M)$ and tetrodotoxin (0.2μM). NT-induced contractile responses were abolished in $Ca^{2+}-free$ solution and reduced greatly to near abolition by $10\;{\mu}M$ of verapamil or 0.2 mM of $CdCl_2.$ Verapamil attenuated the effects of NT on frequency and amplitude of the slow waves. Taken together, these results indicate that NT enhances contractility in guinea-pig gastric antral circular muscle and $Ca^{2+}$ influx through the voltage-operated $Ca^{2+}$ channel appears to play an important role in the NT-induced contractile mechanism.

• The Korean Journal of Physiology
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• 제22권2호
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• pp.219-230
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• 1988

The effect of glycine, structurally the most simple amino acid was investigated on the electrophysiological characteristics of the isolated superfused atrial muscle and sinus node cells of the rabbit heart. Superfusion of the sinus node cell with glycine solution (3, 5 and 8 mM) produced concentration-dependent increments of OS (overshoot potential) and MDP (maximum diastolic potential). Generally action potential amplitude increased as a result of greater increment of OS than that of MDP. The changes in action potential of the sinus node cell peaked in $7{\sim}10{\;}minutes$ after onset of superfusioin. On the contrary to the response to intravenously administered glycine, the rate of spontaneous firing of sinus node cell was invariably increased following superfusion with glycine. Action potential duration manifested as $APD_{60}$ (time to 60% repolarization) was significantly shortened by glycine. And the electrophysiological effects of glycine on the atrial muscle cell were similar to that on the sinus node cells. The results of present study suggest that glycine can exert direct effects on the atrial muscle and sinus node cells of the rabbit heart.

• Carbon letters
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• 제25권
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• pp.14-24
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• 2018

Electrochemical properties and performance of composites performed by incorporating metal oxide or metal hydroxide on carbon materials based on graphene and carbon nanotube (CNT) were analyzed. From the surface analysis by field emission scanning electron microscopy and field emission transmission electron microscopy, it was confirmed that graphene, CNT and metal materials are well dispersed in the ternary composites. In addition, structural and elemental analyses of the composite were conducted. The electrochemical characteristics of the ternary composites were analyzed by cyclic voltammetry, galvanostatic charge-discharge tests, and electrochemical impedance spectroscopy in 6 M KOH, or $1M\;Na_2SO_4$ electrolyte solution. The highest specific capacitance was $1622F\;g^{-1}$ obtained for NiCo-containing graphene with NiCo ratio of 2 to 1 (GNiCo 2:1) and the GNS/single-walled carbon $nanotubes/Ni(OH)_2$ (20 wt%) composite had the maximum specific capacitance of $1149F\;g^{-1}$. The specific capacitance and rate-capability of the $CNT/MnO_2/reduced$ graphene oxide (RGO) composites were improved as compared to the $MnO_2/RGO$ composites without CNTs. The $MnO_2/RGO$ composite containing 20 wt% CNT with reference to RGO exhibited the best specific capacitance of $208.9F\;g^{-1}$ at a current density of $0.5A\;g^{-1}$ and 77.2% capacitance retention at a current density of $10A\;g^{-1}$.

• 공업화학
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• 제28권3호
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• pp.326-331
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• 2017

캐스터오일은 수소화반응을 통해 계면활성제의 중간체 등 유용한 화학산업의 원료로 활용 가능하다. 본 연구에서는 캐스터오일의 수소화용 니켈촉매의 제조조건과 전처리 조건에 대한 영향을 연구하였다. 니켈촉매는 침전제와 pH를 다르게 하여 실리카 담체상에 침전법으로 담지되었고, 다시 산화와 환원의 반복된 전처리를 행하였다. 니켈촉매의 활성은 캐스터오일의 요오드 가를 측정하여 비교하였고, 니켈촉매의 분산도는 XRD, BET, TEM을 통하여 분석하였다. 니켈촉매의 활성을 CO산화반응실험을 통하여도 비교하였다. 산화와 환원 사이클의 반복에 의해 니켈의 재분산이 실리카 상에서 발생하였고, 이것이 캐스터오일 수소화반응 활성을 증진시키는데 기여하였다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.243-247
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• 2012

The paper focuses on an anti-reflection (AR) coating deposited by PECVD in silicon solar cell fabrication. AR coating is effective to reduce the reflection of the light on the silicon wafer surface and then increase substantially the solar cell conversion efficiency. In this work, we carried out experiments to optimize double AR coating layer with silicon nitride and silicon oxide for the silicon solar cells. The p-type mono crystalline silicon wafers with $156{\times}156mm^2$ area, 0.5-3 ${\Omega}{\cdot}cm$ resistivity, and $200{\mu}m$ thickness were used. All wafers were textured in KOH solution, doped with $POCl_3$ and removed PSG before ARC process. The optimized thickness of each ARC layer was calculated by theoretical equation. For the double layer of AR coating, silicon nitride layer was deposited first using $SiH_4$ and $NH_3$, and then silicon oxide using $SiH_4$ and $N_2O$. As a result, reflectance of $SiO_2/SiN_x$ layer was lower than single $SiN_x$ and then it resulted in increase of short-circuit current and conversion efficiency. It indicates that the double AR coating layer is necessary to obtain the high efficiency solar cell with PECVD already used in commercial line.