• 한국축산식품학회지
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• 제38권5호
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• pp.866-877
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• 2018

Cheese emulsion is an intermediate product for the production of cheese powder and needs to be stable, homogeneous and pumpable characteristics to convey to the spray drier. This study was conducted to evaluate the effects of fat reduction and emulsifying salt (ES) amount in cheese emulsion systems on the physicochemical characteristics. Reduced-fat (RF) and full-fat (FF) white-brined cheese emulsions were produced with different dry matters (DM; 15%-25% excluding ES) and ES concentrations (0%-3% based on cheese weight). Stable cheese emulsion was obtained at lower DM in RF cheese emulsion than that of FF cheese emulsion. Reduction in the amount of ES resulted in instability of both emulsions. Apparent viscosity with pseudoplastic flow behavior significantly increased with the decrease of fat content in stable cheese emulsions. Microstructure of emulsions appeared to be related to the fat content, stability and degree of emulsification. Reduction of fat content caused to get less lightness and more greenness in color, whereas yellowness was significantly decreased by increase in the amount of ES. In conclusion, fat reduction resulted in higher viscosities of cheese emulsion due to inducing the increment of protein, and the addition amount of ES considered as very important factor to produce stable cheese emulsion without protein precipitation or cream separation. Therefore, for preparation of RF cheese emulsion using a variety of white-brined cheese, lower amounts of DM would be suggested in this study to obtain homogenous droplets in the atomizing process of spray drying.

• 한국식품과학회지
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• 제20권6호
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• pp.812-819
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• 1988

토마토케찹의 리올로지 성질을 온도 $30-90^{\circ}C$, 농도 15-50% 전단속도 $0-250sec^{-1}$띤 범위에서 Brabender viscotron를 사용하여 측정한 결과는 다음과 같다. 토마토케찹은 전단속도 $0-210sec^{-1}$에서 의가소성을 나타내며, 항복응력을 가지는 Binghampseudoplastic으로 시간의존성을 나타내는 thixotropic 식품이었다. 전단속도 $0-210sec^{-1}$, 온도 $30^{\circ}C$, 농도 33%의 경우 유동지수, 점조도지수 및 항복응력은 각각 0.2131, 22.5047$(Pasec^{-n})$ 및 8.5443(Pa)이었다. 토마토케찹의 온도 및 농도에 따른 겉보기 점도 관계식은 각각 Andrade및 Power type식으로 나타낼 수 있었으며, 또한 온도와 농도에 따른 겉보기점도 관계식은 지수함수 모델로 표현할 수 있었다. 활성화 에너지는 농토 15,20,30,33,40 및 50%에서 3.973, 4.985, 5.078, 5.226, 5.357 및 7.655 kcal/g mole이었다.

• Natural Product Sciences
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• 제21권2호
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• pp.104-110
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• 2015

The activities on the inhibition of NO on LPS-induced RAW 264.7 macrophages were investigated in this work. A simple and sensitive method has been developed and validated for fingerprinting analysis of leaves of Acanthopanax gracilistylus W.W. Smith (AGS). The cytotoxicity and inhibition of NO on LPS-induced RAW 264.7 cells of the extract and triterpenoids were determined. Optimal conditions of HPLC analysis were established as follows. The separation was performed with an ODS-C₁₈ column at $30^{\circ}C$, the detected wavelength was 210 nm, the flow rate was 1 mL/min, and the mobile phase consisted of acetonitrile (0.05% phosphoric acid)-0.05% phosphoric acid solution with gradient elution. Our results showed that impressic acid and acankoreaogenin was more effective on the inhibition of NO than the methanol extract and other compounds. There were seventeen peaks coexisted with similarities above 0.95 and nine lupane-triterpenoids including acankoreaogenin and impressic acid detected and identified. The result of anti-inflammatory activities provides a potential explanation for the use of AGS leaves as a herbal medicine in the treatment of inflammatory diseases. Our results also show that acankoreanogenin and impressic acid may be potentially useful in developing new anti-inflammatory agents. In addition, the fingerprint chromatography clearly illustrated and confirmed the material basis for the anti-inflammatory activities of this plant.

• Natural Product Sciences
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• 제14권3호
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• pp.147-151
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• 2008

A high performance liquid chromatographic (HPLC) method for the simultaneous determination of marker constituents, baicalin and glycyrrhizin was established for the quality control of traditional herbal medicinal preparation, Eul-Ja-Tang (EJT). Separation and quantification were successfully achieved with a Waters XTerra RP18 column ($5{\mu}m$, 4.6 mm I.D. ${\times}$ 150 mm) by gradient elution of a mixture of acetonitrile and water containing 0.03% phosphoric acid (pH 2.03) at a flow rate of 1.0 mL/min. The diode-array UV/VIS detector (DAD) was used for the detection and the wavelength for quantification was set at 250 nm. The presence of baicalin and glycyrrhizin in this decoction was ascertained by retention time, spiking with each authentic standard and UV spectrum. Both baicalin and glycyrrhizin showed good linearity ($r^2$ > 0.999) in a relatively wide concentration ranges. The R.S.D. for intra-day and inter-day precision was less than 5% and the limits of detection (LOD) were about 30 ng. The mean recovery of each compound was 99.5 - 101.2% with R.S.D. values less than 4.0%. This method was successfully applied to the determination of contents of baicalin and glycyrrhizin in three commercial products of EJT, which resulted in the difference in the contents of these compounds. These results suggest that the developed HPLC method is simple, effective and could be readily utilized as a quality control method for commercial EJT products.

• Natural Product Sciences
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• 제16권4호
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• pp.233-238
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• 2010

In order to facilitate the quality control of Artemisia capillaris, a simple, accurate and reliable HPLC method was developed for the simultaneous determination of the six bioactive compounds: scopolin (1), chlorogenic acid (2), 2,4-dihydroxy-6-methoxyacetophenone 4-glycoside (3), hyperoside (4), isorhamnetin 3-Orobinobioside (5), and scoparone (6), which were selected as the chemical markers of A. capillaris. Separation was achieved on an Agilent Eclipse XDB-C18 column with a gradient solvent system of 0.1% trifluoroacetic acid aqueous-acetonitrile at a flow-rate of 1.0 mL/min and detected at 254 nm. All six calibration curves showed good linearity ($R^2$ > 0.998). A simple reversed phase HPLC method was developed for extracting pharmacologically active compounds scopolin, chlorogenic acid, 2,4-dihydroxy-6-methoxyacetophenone 4-glycoside, hyperoside, isorhamnetin 3-O-robinobioside, and scoparone from A. capillaris using a binary gradient of acetonitrile : 0.1% trifluoroacetic acid with UV detection at 254 nm. The scopolin (1), chlorogenic acid (2), 2,4-dihydroxy-6-methoxyacetophenone 4-glycoside (3), hyperoside (4), isorhamnetin 3-O-robinobioside (5), and scoparone (6) contents of the herb of A. capillaris collected from fifteen district markets in Korea were 0.00~0.90 mg/g, 0.06~7.29 mg/g, 0.06~0.91 mg/g, 0.07~5.05 mg/g, 0.42~13.11 mg/g, and 1.11~29.82 mg/g, respectively. The results demonstrated that this method is simple and reliable for the quality control of A. capillaris.

• 대한방사성의약품학회지
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• 제5권2호
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• pp.71-78
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• 2019

Nuclear imaging is one of the most powerful measures for non-invasive diagnosis of myocardial vascular disease. Radionuclide such as ¹³N, ¹⁵O, ²⁰¹Tl and ⁸²Rb is used for the measurement of cardiac blood flow. ¹³N, ¹⁵O and ²⁰¹Tl are produced in cyclotrons while ⁸²Rb is obtained from generator. Rubidium (Rb), an alkali ion, behaves biologically like potassium, and accumulates in myocardial tissue. Rb has rapid blood clearance profile which allows the use of ⁸²Rb with a short physical half-life of 75 s for non-invasive evaluation of regional myocardial perfusion. There are several advantages of ⁸²Rb over other radioisotopes. An ultra-short half-life significantly reduces the exposure of patients to radiation and allows to repeat injections for studying the effects of medical intervention. As a positron emitter, ⁸²Rb allows positron emission tomography (PET) imaging which have shown superior diagnostic performances. ⁸²Rb can be produced from generator by decay of its parent ⁸²Sr. However, the preparation of ⁸²Sr is difficult, because appropriate purity is required to meet the specification of the product. Recently reported procedure from ARRONAX research institute showed that a Chelex-100 resin is sufficient for this purpose and additional column is not necessary. Whereas Brookhaven National Laboratory (BNL) procedure contains three ion exchange resin separation, including Chelex-100 resin. Currently, since ⁸²Sr production site is non-existent in Korea, Korea Atomic Energy Research Institute (KAERI) has plan to produce ⁸²Sr within specifications. We compared ⁸²Sr purification procedures reported from ARRONAX and BNL to investigate the most suitable procedure for our conditions.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2009년도 학술대회
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• pp.944-948
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• 2009

휴대전화는 현재 가장 사적인 이동통신 수단으로 범용인증가입모듈의 보급과 함께 그 개인화 특성이 극대화 되고 있다. 본 연구에서는 휴대전화의 기능 모형을 도출하고 이를 기능 관계 모델을 사용하여 휴대전화의 개인화 기능 관계 모델을 제시하고, 그 작업을 분석한다. 제품의 기능 사이의 관계를 보여줄 수 있는 기능 관계 모델을 도출하기 위해 기능, 작업, 작업의 흐름, 작업의 목적, 기능범주, 기능범주와 기능 간의 영향 등을 사용하였으며, 이를 사용하여 최신 휴대전화의 기능 관계 모델을 작성하였다. 최근 휴대전화 3 개 모델로 만든 기능 관계 모델은 320 여개의 기능과 21 개의 기능 범주가 도출된 기능 모형을 기반으로 만들어졌다. 이를 개인화 기능을 중심으로 기능 관계를 모델링하게 되면 개인화 기능을 위한 정보가 저장되고 사용되는 내/외장 메모리가 모델의 중심에 놓이게 되는 기능 관계 모델이 도출되고, 저장과 조회, 연동 및 검색 등이 주요 작업이 된다, 휴대전화에서 개인화 기능 강화를 위해서는 각 기능간의 관계에 해당하는 작업을 강화하는 것이 주요하다.

• 한국미생물·생명공학회지
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• 제9권1호
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• pp.35-44
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• 1981

대장균이 생산하는 페니실린 아미다제를 젤라틴에 포괄시켜 사출한 후 글루트알데히드로 가교하여 고정화하였다. 이렇게 하여 만들어진 고정화효소는 약 70%의 높은 효소역가를 나타내었고 보관 및 반응조에서 좋은 안정성을 보여주었다. 반응조 내에서의 효소역가 반감기는 약 50일이었으며 최적 PH 및 온도는 각각 8.5와 5$0^{\circ}C$로 나타났다. 효소역가에 미치는 pH 및 온도의 영향은 고정화하기 전과 큰 차이가 없었으나 고온에서의 안정성이 증가되었다. 기질용액으로 완충액을 사용하여 column을 사용하는 관형식 반응조에서의 반응생성률에 기인하는 pH 감소효과를 최소한으로 줄이므로써 효소반응조를 최적화하였다. 반응조 조작상의 중요한 인자 즉 기질농도, 체류시간, 반응 생성물로의 전환율 및 이에 따르는 생산성을 pH 감소효과와 연관시켜 최적반응조건을 논의하였다.

• Journal of Electrical Engineering and Technology
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• 제8권5호
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• pp.1175-1181
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• 2013

The aim of this paper is to design and evaluate a high concentration, high penetration unipolar corona ionizer. The electrostatic characteristics in terms of voltage-current relationships of the present ionizer in the discharge zones for positive and negative coronas were discussed. Using ion current measurement, the concentration and penetration of ions were evaluated at corona voltages across the needle electrodes between 1 and 4 kV, flow rates between 1 and 5 L/min, and an operating pressure of 1 atm. In the discharge zone of the ionizer, the highest ion concentrations were found to be about $1.71{\times}10^{14}$ and $5.09{\times}10^{14}\;ions/m^3$ for positive and negative coronas, respectively. At the outlet of the ionizer, it was found that the highest ion concentration was about $1.95{\times}10^{13}$ and $1.91{\times}10^{13}\;ions/m^3$ for positive and negative coronas, respectively. The highest ion penetration for positive and negative coronas through the ionizer was found to be about 98 % and 33 %, respectively. The $N_it$ product for positive and negative coronas was also found to $1.28{\times}10^{13}$ and $7.43{\times}10^{13}\;ions/m^3s$, respectively. From the findings, this ionizer proved to be particularly useful as an aerosol charger for positive and negative charge before the detector in an electrical aerosol detector.

• 대한기계학회논문집B
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• 제41권10호
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• pp.639-647
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• 2017

Solid SCR에 사용 가능한 암모니아 저장물질의 하나인 암모니움 카바메이트는 열 분해시 이산화탄소 가스와 암모니아 가스를 생성하며, 분해 온도인 $60^{\circ}C$ 이하에서 암모니움 염으로 재결합되는 단점이 있다. 이러한 재결합 현상을 극복하기 위하여, 희석기체인 압축공기를 이용하여 기초가시화 실험을 수행하였다. 또한, 재결합 현상을 계량화하기 위하여, 재결합 물질의 무게변화를 측정하기 위한 간단한 장치를 만들어 자동차환경에서 사용되는 SUS재질의 3가지 관경에 크기에 대한 상관관계를 검토하였다. 아크릴 튜브로 제작된 온도조절이 가능한 가시화 실험장치에, 암모니아 가스, 이산화탄소 가스, 희석기 체인 질소 가스를 공급하며, 재결합 방지를 위한 온도, 압력, 희석유량과의 관계를 고찰하고, Chapman-Enskog Theory에서 파생된 Diffusivity를 사용하여 재결합 조건을 유추할 수 있는 지표로 사용하고자 한다.