• Title/Summary/Keyword: (D/C) ratio

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Optimization of Extraction Process for Total Polyphenols from Angelica Using Response Surface Methodology (반응표면분석법을 이용한 안젤리카로부터 폴리페놀 성분의 추출공정 최적화)

  • Lee, Seung Bum;Park, Bo Ra;Hong, In Kwon
    • Applied Chemistry for Engineering
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    • v.29 no.3
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    • pp.325-329
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    • 2018
  • In this study, polyphenols were extracted from Angelica, which are known to have a high antioxidant content and the extraction process was optimized using the response surface methodology. The extraction yield and the total polyphenols were set as response values for the methodology. Quantitative factors in the extraction process were the extraction time, volume ratio of alcohol/ultrapure water, and extraction temperature. When considering both the main and interaction effects, the greatest influence factor on the extraction yield and total polyphenols was the extraction time. The optimum extraction time and temperature and alcohol/ultrapure water volume ratio for angelica were 2.8 h, $56.6^{\circ}C$ and 64.0 vol% respectively. The extraction yield and total polyphenols when using the conditions were calculated to be 24.6% and 8.76 mg GAE/g. respectively. Determination coefficients of regression equations for the extraction yield and total polyphenols were 81.4 and 75.4%, respectively. Also the overall satisfaction level was found to be 0.80 and the significance was confirmed within 5%.

Prevalence of Fatty Liver and Its Association with Indices of Obesity, Liver Function and Hyperlipidemia among Adult Males (성인 남성의 지방간과 비만, 간기능 및 고지혈증 지표와의 관련성)

  • Lee, Kyu-Sun;Kim, Kwang-Hwan;Cho, Young-Chae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.6
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    • pp.1414-1423
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    • 2009
  • The purpose of the present study was to elucidate such a relationship by comparing the indices of obesity, liver function, and hyperlipidemia with & without fatty liver by using data from health check-up for the adult males in a university hospital. Study subjects were 772 adult males of 30 years and over, who underwent health package check-up at the health promotion center of a university hospital. The prevalence rates of fatty liver of study subjects were 25.5%, and this study shows that fatty liver by abdominal ultrasound has a close correlation with indices of obesity(body weight, BMI, body fat, waist to hip ratio, & waist to stature ratio), liver function(AST, ALT,& GGT), and hyperlipidemia(TG, TC, & HDL-C), and that was independent of age that was relevant.

Design of the Green Wall System considering Distribution Effect of Earth Pressure by Soil Nail (네일의 토압분담 효과를 고려한 Green Wall 시스템의 설계)

  • Park, Si-Sam;Cho, Sung-Han;Yoo, Chan-Ho;Kim, Hong-Taek;Kim, Yong-Yeon
    • Proceedings of the Korean Geotechical Society Conference
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    • 2006.03a
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    • pp.1038-1045
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    • 2006
  • The Green Wall is highest eco-system among a segmental retaining wall systems. Recently, the demand of high segmental retaining wall (SRW) is increased in domestic. The soil nailing system is applied in order to maintain the high SRW stability for steeper slope. However, the proper design approach that can consider the earth pressure reduction effects in soil nailing system has not been proposed. This study was performed to introduce the design case by 'Two-Body Translation mechanism' to be able to consider distribution of earth pressure in the soil nailing when designing the green wall using soil nailing system. Also, this study attempts to evaluate the earth pressure change when advanced soil nailing system is constructed using $FLAC^{2D}$ ver. 3.30 program and 'Two-Body Translation mechanism'. Also in this study, various parametric studies using numerical methods as shear strength reduction (SSR) technique and limit equilibrium technique were carried out. In the parametric study, the length ratio and the bond ratio of the soil nailing were changed to identify the earth pressure reduction effect of the retaining wall reinforced by soil nailing.

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Shrinkage and Creep Behavior of Annealed PET Filament in High Speed Spinning (고속방사 PET filament의 열처리에 따른 수축 및 Creep 거동에 관한 연구)

  • Park, Young-Kun;Koo, Ja-Gil;Chang, Dong-Ho
    • Textile Coloration and Finishing
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    • v.9 no.4
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    • pp.7-19
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    • 1997
  • The purpose of the study was to investigate the shrinkage and creep behavior of PET filaments which were prepared at various spinning speeds(3,300, 4,000, 5,000, 6,000, and 7,000m/min) and anneal($120^{\circ}$, 30min & $150^{\circ}$, 40min). In order to determine the shrinkage and creep behavior with the crystallinity change, PET filaments were treated with low(12$0^{\circ}C$, 30min) and high($150^{\circ}$, 40min) temperature conditions with hot air dryer under the constant tension. The results of the study were as follows: as the spinning speed increased, the degree of shrinkage and elongation of the sample treated by wet condition decreased. The sample with 0.01g/d of load under various spinning speeds showed shrinkage behavior and highest shrinkage ratio at $76^{\circ}$ which was Tg of PET. The degree of shrinkage and elongation of the treated sample was less than those of the untreated sample by wet treatment. Especially, there was less degree of shrinkage and elongation of the sample treated by higher temperature condition. In 3,300m/min of spinning speed the draw ratio of undrawn yarn of a mixture of a-axis orientation and c-axis orientation was 2.0, which is similar to the value of the traditional drawn yarn. Finally, there was a big range of shrinkage and elongation by wet treatment in 3,300 m/min of spinning speed.

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A study of Utilization behavior in patients receiving Korean Medicine and Western Medicine collaboration (의·한의 협진 의료이용 행태 분석 연구)

  • Kim, Hyun-Min;Kim, Nam-Kwen;Nam, Soon-Hoo;Lee, Hye-Yoon
    • Journal of Society of Preventive Korean Medicine
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    • v.22 no.2
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    • pp.25-32
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    • 2018
  • Objectives : This study was conducted to investigate the frequent diseases among the people who had been treated by collaborative treatment of Korean medicine and Western medicine, and to compare their medical use behaviors before and after the collaborative first-stage pilot project between Korean medicine and Western medicine. Methods : 4,467 patients were identified as the patients who are participated in the collaborative first-stage pilot project between Korean medicine and Western medicine during the period between July 15, 2016 and March 31 2017. We used 28,480 records of Korean national health insurance claim data from January 1 2016 to March 31 2017 to analyzed present condition of cooperative medical usage. Also we conducted a paired t test to compare the percentage of collaborative treatment days before and after the pilot project period. Results : We found that the most frequent diseases treated in the pilot project were the diseases of musculoskeletal and nervous system and then 10 major diseases such as H, K, J, C (D), N, L, E, A, H and F disease codes in order. Also it was confirmed that 14 major and 53 medium diseases are included from more than 90% of total patients. As a result of high frequency of medical treatment in Western medicine or Korean medicine is "administration of Korean medicine", which is same as before and within the pilot project. The ratio of utilizing both Western and Korean medical care for the same disease on the same day by both general patients and patients in KCD-7 disease code group C, G, I, M and S had been increased significantly. Conclusions : The pilot project might change the behavior of utilizing the medical care service by increasing the ratio of collaborative treatment of Western medicine and Korean medicine for the same disease on the same day.

Optimization of Iced Cookie with the Addition of Dried Sweet Pumpkin Powder (건조 단호박을 첨가한 냉동쿠키의 제조조건 최적화)

  • Lee, Sun-Mee;Ko, Young-Joo;Jung, Hyeon-A;Paik, Jae-Eun;Joo, Na-Mi
    • Journal of the Korean Society of Food Culture
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    • v.20 no.5
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    • pp.516-524
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    • 2005
  • This study was conducted to develop a functional cookie with the addition of a sweet pumpkin powder on a cookie shape, that showed high preference level to all age group and that was very easily to store because of low moisture content, by substituting partially a sweet pumpkin powder for reducing content of wheat flour. This study has produced the sensory optimal composite recipe by making iced cookies, respectively, with each 5 level of Sweet pumpkin powder($X_{1}$), sugar($X_{2}$), butter($X_{3}$), by C.C.D(Central Composite Design) and conducting sensory evaluation and instrumental analysis by means of RSM(Response Surface Methodology). Sensory items showed very significant values in color, appearance, flavor, overall quality(p<0.05), texture(p<0.01), and instrumental analysis showed significant values in lightness, redness(p<0.01), yellowness, spread ratio, hardness(p<0.05). Also sensory optimal ratio of Sweet pumpkin cookie was calculated as sweet pumpkin powder 81.8g, sugar 116.6g, butter 210.7g, and it was revealed that the factors of influencing cookie aptitude were in order of Sweet pumpkin powder, butter, sugar.

Effect of Operation Conditions on Pyrolysis of Larch Sawdust in a Bubbling Fluidized Bed (기포유동층 반응기를 이용한 낙엽송 톱밥의 열분해 특성)

  • Yoo, Kyung-Seun;Eom, Min-Seop;Lee, See Hoon
    • Applied Chemistry for Engineering
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    • v.27 no.5
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    • pp.478-482
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    • 2016
  • In this study, a bubbling fluidized bed pyrolyzer (0.076 m I.D. and 0.8 m high) was employed to investigate the fast pyrolysis characteristics of larch sawdust which is abundant in Korea. The effects of operation conditions, such as bed temperature ($350-550^{\circ}C$), fluidization velocity ratio ($U_o/U_{mf} $: 2.0-6.0) and feeding rate (2.2-7.0 g/min) on product yields and their chemical components were studied. The number of chemical compounds in the bio-oil decreased with the increasing bed temperature because of secondary pyrolysis. The effects of the Uo/Umf ratio and feeding rate on bio-oil compositions were relatively lower than those of the bed temperature.

Fabrication and Characterization of Environmentally Friendly PLA/PPC/PLA Multilayer Film (친환경 PLA/PPC/PLA 적층필름의 제조 및 특성 연구)

  • Lee, Deuk-Young;Kim, Kyung-Youn;Cho, Misuk;Nam, Jaedo;Lee, Youngkwan
    • Polymer(Korea)
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    • v.37 no.2
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    • pp.249-253
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    • 2013
  • From poly(lactic acid) (PLA) and poly(propylene carbonate) (PPC) synthesized using $CO_2$, a PLA/PPC/PLA layered film is prepared by coextrusion and then stretched to uniaxial orientation. The mechanical, optical, and barrier properties and shrinkage of the prepared film were investigated in detail. The maximum shrinkage of PLA/PPC/PLA film reached to 60% at $75^{\circ}C$. With increasing PPC content, the ratio of shrinkage of the film was increased and its shrinkagerate was increased. The ratio of shrinkage of the film decreased with increasing stretching temperature. The prepared film has oxygen and vapor transmission barrier properties. In this study, the PLA/PPC/PLA film is expected to be commercialized as a environmentally friendly shrinkable film.

Formation of Cobalt Ferrite Epitaxial Iron Oxide and Their Magnetic Properties(II) (코발트 훼라이트 에피탁시얼 산화철의 생성과 자기특성(II))

  • Byeon, T.B.;Kim, D.Y.;Lee, J.Y.;Lee, H.;Sohn, J.G.;Han, K.H.
    • Journal of the Korean Magnetics Society
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    • v.2 no.1
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    • pp.15-21
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    • 1992
  • Acicular ${\gamma}-Fe_{2}O_{3}$ particles were heated at $90^{\circ}C$ in alkaline solution containing mixed solution of dyadic metal with $Co^{+2}/Fe^{+2}$ ratio of 0.5. When cobalt content was increased, the coercivity of resultant product increased linearly, and surface area decreased. The cobalt ferrite was grown epitaxially on the surface ${\gamma}-Fe_{2}O_{3}$ crystal, and the increase of coercivity was attributed to the crystalline magnetic anisotropy of the cobalt ferrite which is conform to coating layer. We can expect superior magnetic properties above normal ratio of 2. The progress of reaction has an effect on coercivity of cobalt ferrite epitaxial iron oxide. The stability of temperature and the change om standin& of $Co-{\gamma}-Fe_{2}O_{3}$ was largely influenced by the composition of coating layer.

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A Study on Synthesis of Acrylic Pressure Sensitive Adhesive for Polarizer Film by Solution Polymerization (용액중합에 의한 편광필름용 아크릴 점착제의 합성에 관한 연구)

  • Lim, Chang-Hyuk;Jung, Young-Jae;Cho, Ur-Ryong
    • Elastomers and Composites
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    • v.44 no.2
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    • pp.175-181
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    • 2009
  • The solution polymerization was conducted to synthesize pressure sensitive adhesive for polarizer film using acrylic monomers. 2-Ethylhexyl acrylate, butyl acrylate, acrylic acid were used as acrylic monomers, benzoyl peroxide as initiator, ethyl acetate as solvent. The ratio of monomers was 2-ethylhexyl acrylate: butyl acrylate: acrylic acid = 25:50:3.6 reflecting $-40^{\circ}C$ of glass transition temperature in the pressure sensitive adhesive. The amount of initiator was determined as 0.09% to monomer considering wetting power and initial tackiness. The ratio of monomer to solvent was determined as 1:1.7 considering wetting power and transmissivity. The transmissivity of pressure sensitive adhesive increased with decreasing both viscosity and molecular weight due to reducing of refractive index by low entanglement between molecules. In the measurement of pot life, it was found that the storage stability was good at 1:1.7 of monomer: solvent without large change of viscosity during 200 min.