• Title/Summary/Keyword: high-heated

검색결과 947건 처리시간 0.029초

몽골지역 시멘트를 활용한 극한환경 콘크리트 성능평가 (Properties of Cold weather Concrete using Mongolia Cement)

  • 유조형;김우재;홍석범
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2016년도 추계 학술논문 발표대회
    • /
    • pp.89-90
    • /
    • 2016
  • In the cold-weathering(Mongolian region) concrete construction, this purpose of this research is the evaluation on the performance of concrete using various binders such as Mongolian cement, Chinese cement and high blane-self heated cement.

  • PDF

시판 표준 생식의 전분 가수분해지수에 열처리가 미치는 영향 (Effect of Heat Treatment on In Vitro Hydrolysis Index of Commercial Saengshik)

  • 한성희;한상윤;이철
    • 한국식품영양학회지
    • /
    • 제21권4호
    • /
    • pp.470-476
    • /
    • 2008
  • In this study, we assessed the effects of heat treatment on the in vitro hydrolysis indices of commercial Saengshik. Thermal treatment on grain flour and commercial Saengshik increased soluble dietary finer(SDF) and insoluble fiber(IDF), while total dietary fiber(TDF) content remained nearly constant regardless of thermal treatment. Among the samples, COS(Commercial Ohaeng Saengshik) showed the highest TDF and IDF content in raw and heated samples. Additionally, the resistant starch(RS) contents in unheated samples were shown to be high. After heating, the RS levels of all the samples were reduced significantly, by over 12%. The degree of gelatinization in the unheated samples was lower than that of the heated samples, whereas the degree of retrogradation in the unheated samples was higher than that of the heated samples. The hydrolysis indices(HI) of the unheated samples were relatively low, whereas the heated group evidenced high levels. The HI must be affected by content of RS and IDF in samples.

Characteristics of Sucrose Thermal Degradation with High Temperature and High Pressure Treatment

  • Woo, Koan-Sik;Hwang, In-Guk;Lee, Youn-Ri;Lee, Jun-Soo;Jeong, Heon-Sang
    • Food Science and Biotechnology
    • /
    • 제18권3호
    • /
    • pp.717-723
    • /
    • 2009
  • Thermal degradation characteristics of sucrose was investigated. A 20% sucrose solution was heated to temperatures of $110-150^{\circ}C$ for 1-5 hr. Chromaticity, pH, organic acids, 5-hydroxymethylfurfural (HMF), free sugars, electron donating ability (EDA), and ascorbic acid equivalent antioxidant capacity (AEAC) of the heated sucrose solutions were evaluated. With increasing temperatures and times, the L-, a-, and b-values decreased; however, total color difference (${\Delta}E_{ab}$) increased. The pH and sucrose contents decreased, and fructose and glucose contents increased with increasing heating temperature and time. Organic acids, such as formic acid, lactic acid, and levulinic acid, and HMF contents increased with increasing heating temperatures and times. EDA (%) and the AEAC of the heated sucrose solutions increased with increasing heating temperature and time. The heated sucrose solution was more effective than unheated sucrose solution, having higher EDA (90 fold), and AEAC (13 fold).

광범위한 압력조건하에서 균일 가열 수직 봉다발에서의 임계열유속 (Critical Heat Flux in Uniformly Heated Rod Bundle Under Wide Range of System Pressures)

  • 문상기;천세영;최기용
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2001년도 춘계학술대회논문집D
    • /
    • pp.195-200
    • /
    • 2001
  • An experimental study on critical heat flux (CHF) has been performed for water flow in a uniformly heated vertical 3 by 3 rod bundle under low flow and a wide range of pressure conditions. The objective of this study is to investigate the parametric trends of CHF with 3 by 3 rod bundle test section where three unheated rods exist. The general trends of the CHF are coincident with previous understandings. At low flow and system pressure above 3 MPa, some critical qualities are larger than 1.0 due to counter-current flow in test sections. Since there is a supply of water to the heated section from unheated section, the maximum CHFs at system pressure between 2 and 4 MPa are not shown.

  • PDF

균일 가열 수직 환상관에서 임계열유속조건 직전의 열전달계수에 관한 실험적 연구 (An Experimental Study on Heat Transfer Coefficients just before Critical Heat Flux Conditions in Uniformly Heated Vertical Annulus)

  • 천세영;임창하;문상기;정문기;최영돈
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2001년도 추계학술대회논문집B
    • /
    • pp.330-336
    • /
    • 2001
  • Water heat transfer experiments were carried out in a uniformly heated annulus with a wide range of pressure conditions. The local heat transfer coefficients for saturated water flow boiling have been measured just before the occurrence of the critical heat flux (CHF) along the length of the heated section. The trends of the measured heat transfer coefficients were quite different from the conventional understanding for the heat transfer of saturated flow boiling. This discrepancy was explained from the nucleate boiling in the liquid film of annular flow under high heat flux conditions.

  • PDF

An Experimental Study on Heat Transfer Characteristics Just Before Critical Heat Flux in Uniformly Heated Vertical Annulus Under a Wide Range of Pressures

  • Chun, Se-Young;Moon, Sang-Ki;Chung, Heung-June;Chung, Moon-Ki
    • Nuclear Engineering and Technology
    • /
    • 제34권4호
    • /
    • pp.269-285
    • /
    • 2002
  • Water heat transfer experiments were carried out in a uniformly heated annulus with a wide range of pressure conditions. The local heat transfer coefficients for saturated water (low boiling have been measured just before the occurrence of the critical heat flux (CHF) along the length of the heated section. The trends of the measured heat transfer coefficients were quite different from the conventional understanding for the heat transfer of saturated flow boiling. This discrepancy was explained from the nucleate boiling in the liquid film of annular flow under high heat flux conditions. The well-known correlations were compared with the measured heat transfer coefficients. The Shah and Kandlikar correlations gave better prediction than the Chen correlation. However, the modified Chen correlation proposed in the present work showed the best agreement with the present data among correlations examined .

Investigation of heating and accretion event of Milky Way disk

  • Lee, Ayeon;Lee, Young Sun;Kim, Young Kwang
    • 천문학회보
    • /
    • 제46권2호
    • /
    • pp.67.2-67.2
    • /
    • 2021
  • We present preliminary results on the chemical and kinematic analysis of accreted and heated metal-rich (-1.0 < [Fe/H] < -0.3) stars in the Galactic disk. These stars are in the ranges of e > 0.7, -100 < V𝜙 < 100 km/s, and |Z| < 3 kpc, and are presumably heated (accreted) by (from) past merger events such as Gaia Enceladus and Sausage (GSE). These stars are largely separated into two groups based on the level of [α/Fe] and radial velocity dispersion. The first group has low [α/Fe] and high radial velocity dispersion, and the second group shows high [α/Fe] and low radial velocity dispersion. We propose that the first group of stars are accreted from the GSE galaxy, whereas the second group of stars are dynamically heated by the GSE merger event.

  • PDF

Zinc-acetate 직접 가열에 의한 ZnO막의 제조 및 산소분위기 영향 (Fabrication of ZnO films from directly heated Zinc-Acetate and oxygen effects on the deposition)

  • 마대영;이수철;김상현;박기철;김기완
    • E2M - 전기 전자와 첨단 소재
    • /
    • 제8권4호
    • /
    • pp.400-405
    • /
    • 1995
  • ZnO films have been grown easily with the conventional thermal evaporation method on SiO$\_$2/ coated Si wafers. Anhydrous zinc acetate has been used as evaporation source. Zinc-acetate was directly heated in the laboratory-made brass boat. Zinc-acetate was sublimed at the boat temperature of about 220.deg. C. The substrates were heated to 600.deg. C with home made tantalium heater. Oxygen has been flowed into the deposition chamber to change the partial pressure of oxygen. X-ray diffraction patterns showed all the films to be amorphous. The films deposited at high oxygen pressure exhibit higher resistivity than films at low pressure. Energy dispersive spectroscopy(EDS) and rutherford backscattering spectrometry(RBS) were conducted on the films to reveal the composition of the ZnO films.

  • PDF

The Voltage-fed High Frequency Resonant Inverter Using Induction Heated Dry Steam Generator

  • Kim, Chil-Ryong;Lee, Jong-Kurl;Jung, Sang-Hwa;Mun, Sang-Pil;Kim, Sang-Don;Nakaoka, Mutsuo
    • 한국조명전기설비학회:학술대회논문집
    • /
    • 한국조명전기설비학회 2008년도 춘계학술대회 논문집
    • /
    • pp.415-418
    • /
    • 2008
  • This paper presents an innovative prototype of a new conceptual electromagnetic induction-based fluid beating appliance using voltage-fed type scries capacitor-compensated load resonant high-frequency IGBT inverter with a phase-shifted PWM and a power factor correction schemes. Its operating characteristics in steady-state are illustrated including unique features and evaluated on the basis of its computer simulation and experimental results of 10kw breadboard appliance for hot water producer and superheated steamer. The promising cost effective inverter-fed boiler appliances for electromagnetic induction-heated type fluid-heating in the pipeline systems are proposed for induction-heated boiler, super heat steamer, high temperature water producer, hot gas producer and metal catalyst heating for exhaust gas cleaning in engine, which are more suitable and acceptable for industrial, chemical, and consumer energy utilization for household and business from a practical point of view.

  • PDF

고압조건에서 가열 처리된 Iysozyme의 변성 (Denaturation of Heat Treated Lysozyme under High Pressure Conditions)

  • 조래광;홍진환
    • 한국식품과학회지
    • /
    • 제23권3호
    • /
    • pp.366-369
    • /
    • 1991
  • 압출성형가공(extrusion cooking)에 의한 단백질의 조직화 메카니즘을 해석하기 위해 난백lysozyme을 고압조건에서 가열처리한 모델계 시료의 불용화 현상과 분자량적인 변화를 조사하였다. $100,\;300,\;600\;kg/cm^2$의 고압조건에서 $70,\;120,\;150^{\circ}C$로 가열온도가 높은 시료일수록 용해성은 감소하였으며 $200^{\circ}C$로 가열한 시료에서는 처리압력이 증가할수록 용해도가 현저히 감소하였다. $150^{\circ}C$$200^{\circ}C$로 가열처리한 시료에서는 dimer 이상의 polymer가 생성되었고 monomer보다 분자량이 작은 band의 생성도 인정되었는데 그 추정 분자량은 약 $6,000{\sim}9,000$의 분포이었으며 이 보다 저분자의 peptide는 존재하지 않았다. $120^{\circ}C$에서 가열한 시료의 고분자 형성은 주로 분자간 disulfide 결합에 의한 것이었고 $150^{\circ}C$ 이상으로 가열한 시료의 고분자 형성에는 disulfide결합 이외의 분자간 결합도 상당수 관여한 것으로 판단된다.

  • PDF