• Title/Summary/Keyword: Heating Characteristics

Search Result 2,429, Processing Time 0.027 seconds

Effect of Dietary Mugwort on the Physico-Chemical Properties of Chicken Meat (쑥의 급여가 계육의 이화학적 특성에 미치는 영향)

  • 박창일
    • Food Science of Animal Resources
    • /
    • v.22 no.3
    • /
    • pp.212-217
    • /
    • 2002
  • This study was conducted to investigate the influence of dietary mugwort on physico-chemical characteristics and processing characteristics in meat sample of chicken meat. Broilers were randomly assigned to one of four dietary treatments: 1) Control(commercial feed) 2) T1(commercial feed supplemented with 1% mugwort) 3) T2(commercial feed with 3% mugwort) and 4)T3(commercial feed with 5% mugwort). They were fed one of the experimental diets for five weeks and slaughtered. After that, the meat samples were vacuum packaged and stored at 4${\pm}$1$^{\circ}C$. The physico-chemical characteristics and processing characteristics were analyzed for meat samples stored over a period of 0, 1, 2, 3 and 4 weeks. The pH of all treatments significantly increased during the storage periods(U<0.05). The pH of the thigh was rather higher than that of the breast. The drip loss and heating loss tend to decrease in dietary mugwort group(p<0.05). The WHC(water holding capacity) of all treatment was significantly increased during storage(p<0.05). The meat color was increased during storage.

Thermal Resistance Characteristics and Fin-Layout Structure Optimization by Gate Contact Area of FinFET and GAAFET (FinFET 및 GAAFET의 게이트 접촉면적에 의한 열저항 특성과 Fin-Layout 구조 최적화)

  • Cho, Jaewoong;Kim, Taeyong;Choi, Jiwon;Cui, Ziyang;Xin, Dongxu;Yi, Junsin
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.34 no.5
    • /
    • pp.296-300
    • /
    • 2021
  • The performance of devices has been improved with fine processes from planar to three-dimensional transistors (e.g., FinFET, NWFET, and MBCFET). There are some problems such as a short channel effect or a self-heating effect occur due to the reduction of the gate-channel length by miniaturization. To solve these problems, we compare and analyze the electrical and thermal characteristics of FinFET and GAAFET devices that are currently used and expected to be further developed in the future. In addition, the optimal structure according to the Fin shape was investigated. GAAFET is a suitable device for use in a smaller scale process than the currently used, because it shows superior electrical and thermal resistance characteristics compared to FinFET. Since there are pros and cons in process difficulty and device characteristics depending on the channel formation structure of GAAFET, we expect a mass-production of fine processes over 5 nm through structural optimization is feasible.

A Study on the Physicochemical and Sensory Characteristics of Cod Stock by Hot Water Extraction Time (열수추출 시간에 따른 대구육수 이화학적 및 관능특성에 관한 연구)

  • Kim, Dong-Seok;Shin, Kyung-Eun;Lee, Wook;Bae, Gum-Kwang
    • Culinary science and hospitality research
    • /
    • v.20 no.2
    • /
    • pp.89-99
    • /
    • 2014
  • This study aims to make stock using cod bones with the hot water extraction method. Moisture content, chromaticity, pH, salinity, sugar content, mineral contents, quantitative analysis, and overall acceptance were studied to determine the standard formula. The results are as follows. The moisture content decreased (p < 0.001) and color value increased as heating time increased. The pH was highest in CS5 which was heated for 30 minutes and lowest in CS1. The salinity and sugar content significantly increased with more heating time (p < 0.001). In terms of mineral contents, sodium was highest in 138.87~154.17 mg, magnesium and iron showed proportion difference with increased heating time. The mineral analysis test result revealed that sodium, magnesium and iron showed proportional difference with increased heating time, while potassium and calcium did not change. The result of quantitative analysis test showed transparency, fishy smell, delicate flavor, savory flavor, salt taste and umami taste became stronger as high-pressure heating time increased. From these result, CS4 was evaluated to be the best in appearance, flavor, taste, aftertest and overall acceptance. Also, 60 minute high-pressure heating time is the most desirable to produce stock using cod bones as a main ingredient.

Analysis of the Causes of Deformation of Packaging Materials Used for Ready-to-Eat Foods after Microwave Heating (즉석편의 식품용 포장재의 전자레인지 가열에 의한 변형 원인 분석)

  • Yoon, Chan Suk;Hong, Seung In;Cho, Ah Reum;Lee, Hwa Shin;Park, Hyun Woo;Lee, Keun Taik
    • Korean Journal of Food Science and Technology
    • /
    • v.47 no.1
    • /
    • pp.63-69
    • /
    • 2015
  • The aim of this study was to investigate the deformation of packaging materials used for ready-to-eat (RTE) foods after the retort process and microwave heating. From the multilayer films consisting of polyethylene terephthalate (PET), polyamide (PA), and cast polypropylene (CPP) in a stand-up pouch form used for RTE foods, some deformation of the CPP layer, which was in direct contact with the food, was observed after the retort process and microwave heating. The damage was more severely caused by microwave heating than by the retort process. This may be attributed to diverse factors including the non-uniform heating in a microwave oven, the sorption of oil into the packaging film, and the different characteristics of food components such as viscosity, salt and water content. The development of heat-resistant packaging materials and systems suitable for microwave heating of RTE foods is required for the safety of consumers.

Microwave-Syntheses of Zeolitic Imidazolate Framework Material, ZIF-8 (마이크로파에 의한 Zeolitic Imidazolate Framework 물질, ZIF-8의 합성)

  • Park, Jung-Hwa;Park, Seon-Hye;Jhung, Sung-Hwa
    • Journal of the Korean Chemical Society
    • /
    • v.53 no.5
    • /
    • pp.553-559
    • /
    • 2009
  • One of zeolitic imidazolate framework materials (ZIF), ZIF-8, has been synthesized with microwave irradiation and conventional electric heating at $140{\sim}180^{\circ}C}$. ZIFs are porous crystalline materials and are similar to metal organic framework (MOF) materials because both ZIFs and MOFs are composed of both organic and metallic components. ZIFs are very stable and similar to zeolites because ZIFs have tetrahedral networks. ZIF-8, with a decreased crystal size, can be synthesized rapidly with microwave irradiation. The microwave synthesis of ZIF-8 is completed in 4 h at $140{^{\circ}C}$ and the reaction time is decreased by about 5 times compared with the conventional electric heating. The ZIF-8 obtained by microwave heating has larger surface area and micropore volume compared with the ZIF-8 synthesized with conventional electric heating. It can be confirmed that ZIF-8s show type-I adsorption isotherms, explaining the microporosity of the ZIF-8s. Based on FTIR and TGA results, it can be understood that the ZIF-8s have similar bonding and thermal characteristics irrespective of heating methods such as microwave and conventional heating.

Characteristics Analysis of Magnetizing Circuit and Fixture considering Temperature Characteristic (온도특성을 고려한 착자회로 및 요크의 특성 해석)

  • Baek, Soo-Hyun;Maeng, In-Jae;Kim, Pill-Soo;Kim, Cherl-Jin
    • Proceedings of the KIEE Conference
    • /
    • 1993.11a
    • /
    • pp.82-84
    • /
    • 1993
  • A method for simulating general characteristics and temperature characteristics of magnetizing fixture coil of the capacitor discharge impulse magnetizer-magnetizing fixture system using SPICE is presented. This method has been developed which can aid the design, understanding and inexpensive, time-saving of magnetizing circuit. As the detailed characteristics of magnetizing circuit can be obtained, the efficient design of the magnetizing circuit which produce desired magnet will be possible using our SPICE modeling. Especially, The knowledge of the temperature of the magnetizing fixture is very important to forecast the characteristics of the magnetizing circuits tinder different conditions. The capacitor voltage was not raised above 810[V] to protect the magnetizing fixture from excessive heating. The temperature estimation method uses multi-lumped model with equivalent thermal resistance and thermal capacitance.

  • PDF

A Study on the Heat Sink with internal structure using Peltier Module In the Natural and Forced Convection (자연대류와 강제대류에서 펠티에 소자를 이용한 내부터널 구조를 가지는 히트싱크에 관한 연구)

  • Lee, Min;Kim, Tae-Wan
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.15 no.7
    • /
    • pp.4072-4080
    • /
    • 2014
  • The Peltier Module has been used to dissipate the heat from electronic devices and electronic components. In this module, a heat sink is used to release the operating heat into the air outside. This study addressed the heat transfer characteristics for a heat sink with an inner tunnel. Under forced and natural convection conditions, the heat transfer characteristics were different. Therefore, the cooling and heating performances were studied for the heat sink, which has an inner tunnel. The heat transfer conditions were also evaluated by performing an experimental test, which investigated the heat transfer characteristics related to the variance in time and temperature distribution. Experiments on the heat transfer characteristics of the heat sink were conducted based on the forced and natural convection and temperature distribution changes. In the cooling experiment, the A- and B-shaped cooling pin heat sinks decreased the temperature of the forced convection than the temperature of natural convection. In the forced and natural convection, the A- and B-shaped decreased to a minimum of $-15^{\circ}C$. Under the forced and natural convection conditions, A- and B-shaped cooling pin heat sinks decreased the temperature when the voltage was increased. In the heating experiment, the A- and B-shaped cooling pin heat sinks increased the temperature of the forced convection than the temperature of natural convection. In forced convection, when the voltage was $15^{\circ}C$, the temperature of the A-shaped cooling pin heat sink increased to $150^{\circ}C$, and the temperature of the B-shaped cooling pin heat sink increased to $145^{\circ}C$. Under forced and natural convection conditions, the A- and B-shaped cooling pin heat sinks showed an increase in temperature with increasing voltage.

Recent Progress in Air-Conditioning and Refrigeration Research: A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2014 (설비공학 분야의 최근 연구 동향: 2014년 학회지 논문에 대한 종합적 고찰)

  • Lee, Dae-Young;Kim, Sa Ryang;Kim, Hyun-Jung;Kim, Dong-Seon;Park, Jun-Seok;Ihm, Pyeong Chan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.27 no.7
    • /
    • pp.380-394
    • /
    • 2015
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2014. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of heat and mass transfer, cooling and heating, and air-conditioning, the flow inside building rooms, and smoke control on fire. Research issues dealing with duct and pipe were reduced, but flows inside building rooms, and smoke controls were newly added in thermal and fluid engineering research area. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results for thermal contact resistance measurement of metal interface, a fan coil with an oval-type heat exchanger, fouling characteristics of plate heat exchangers, effect of rib pitch in a two wall divergent channel, semi-empirical analysis in vertical mesoscale tubes, an integrated drying machine, microscale surface wrinkles, brazed plate heat exchangers, numerical analysis in printed circuit heat exchanger. In the area of pool boiling and condensing, non-uniform air flow, PCM applied thermal storage wall system, a new wavy cylindrical shape capsule, and HFC32/HFC152a mixtures on enhanced tubes, were actively studied. In the area of industrial heat exchangers, researches on solar water storage tank, effective design on the inserting part of refrigerator door gasket, impact of different boundary conditions in generating g-function, various construction of SCW type ground heat exchanger and a heat pump for closed cooling water heat recovery were performed. (3) In the field of refrigeration, various studies were carried out in the categories of refrigeration cycle, alternative refrigeration and modelling and controls including energy recoveries from industrial boilers and vehicles, improvement of dehumidification systems, novel defrost systems, fault diagnosis and optimum controls for heat pump systems. It is particularly notable that a substantial number of studies were dedicated for the development of air-conditioning and power recovery systems for electric vehicles in this year. (4) In building mechanical system research fields, seventeen studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, and renewable energies, piping in the buildings. Proposed designs, performance performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the evaluation of work noise in tunnel construction and the simulation and development of a light-shelf system. The subjects of building energy were worked on the energy saving of office building applied with window blind and phase change material(PCM), a method of existing building energy simulation using energy audit data, the estimation of thermal consumption unit of apartment building and its case studies, dynamic window performance, a writing method of energy consumption report and energy estimation of apartment building using district heating system. The remained studies were related to the improvement of architectural engineering education system for plant engineering industry, estimating cooling and heating degree days for variable base temperature, a prediction method of underground temperature, the comfort control algorithm of car air conditioner, the smoke control performance evaluation of high-rise building, evaluation of thermal energy systems of bio safety laboratory and a development of measuring device of solar heat gain coefficient of fenestration system.

Thermal Characteristics of LaMnO3 Non-isothermal Synthesis Reaction (LaMnO3 비등온 합성반응의 열적특성)

  • Jeon, Jong Seol;Lee, Jung Hun;Yoon, Chang Hyeok;Yoo, Dong Jun;Lim, Dae Ho;Kang, Yong
    • Korean Chemical Engineering Research
    • /
    • v.54 no.3
    • /
    • pp.404-409
    • /
    • 2016
  • Thermal Characteristics and kinetic parameters of $LaMnO_3$ synthesis reaction were investigated by means of TGA (Thermogravimetric analysis) at non-isothermal heating conditions (5.0, 10.0, 15.0 and 20.0 K/min). The reaction was occurred rapidly at 450~600K (X=0.4~0.7) depending on the heating rate. Activation energy for the synthesis of $LaMnO_3$ from the precursor, which was determined by different method such as Friedman, Ozawa-Flynn-Wall and Vyazovkin methods, was in the range of 23~243 kJ/g-mol depending on the fractional conversion level and estimation method. The reaction order decreased with increasing heating rate and fractional conversional level. The average reaction order was 4.50 in case of X=0.1~0.3, while it was 1.87 in case of X=0.7~0.9, respectively. The value of frequency factor of reaction rate increased with inceasing heating rate and fractional conversion level. The aveage value of frequency factor was 205.6 ($min^{-1}$) when X=0.1~0.3, while it was 475.2 ($min^{-1}$) when X=0.7~0.9, respectively.

A Study on the Treatment of Combustible Wastes and the Resource Recovery by Pyrolysis (熱分解에 의한 可燃性 廢棄物의 처리 및 資源回收에 관한 연구)

  • Kim, Sam-Cwan;Zong, Moon-Shik
    • Journal of Environmental Health Sciences
    • /
    • v.13 no.1
    • /
    • pp.17-33
    • /
    • 1987
  • As a result of technical advances and industrialization, the characteristics of domestic and industrial wastes are becoming more complex. Accordingly, improved treatment and disposal systems are being continuously sought to take account of complex characteristics and to comply with economic restrictions. In this study, an application of pyrolysis to the treatment of industrial wastes, including waste scrap rubber, waste raw material used in making the slipper bottom and waste PVC pipe, and the effectiveness of pyrolysis in resource recovery from these wastes were investigated. Batches of wastes were pyrolysed by external heating to a temperature of 400-800$\circ$C in a 32 mm diameter x 0.9 m long silica tube to produce combustible gases, oils and chars. Before the start of pyrolysis runs, the entire system was purged with nitrogen gas to exclude the air. The temperature inside the retort was controlled by the thermocouple in the gas stream, and referred to as the pyrolysis temperature. Under these conditions three products were separately collected and further analyzed. The results were summarized as follows. 1. More gases and less chars were produced with higher pyrolyzing temperature and with higher rates of heating, but the yields of oils tended downwards at temperatures above 700$\circ$C. Accordingly, operating conditions of pyrolysis should be varied with desired material. 2. Calorific values and sulfur contents of produced oils were sufficient and suitable for fuel use. Chars from waste rubber had high heating values with low sulfur contents, but calorific values of chars from waste PVC and waste slipper were as low as 3, 065-4, 273 kcal/kg and 942-2, 545 kcal/kg, respectively. Therefore, char from these wastes are inappropriate for fuel. 3. Soluble contents of Pb, Cd, Cu and Zn in chars from waste rubber and waste slipper were below the Specific Hazardous Waste Treatment Standards. However soluble contents of Pb and Cd in chars from waste PVC were one or two times and five or seven times exceedingly the Specific Hazardous Waste Treatment Standards, respectively. 4. Post high heating is desirable for treatment method of waste PVC which generates toxic hydrogen chloride. 5. The proportions of hydrogen, methane and ethane in produced gases were in the range of 3.99-35.61% V/V, 18.22-32.50% V/V and 5.17-5.87% V/V, respectively. 6. Pyrolysis is a useful disposal method in case of waste slipper, which was hardly combustible, and thus investigations of this kind of materials are required for effective management of industrial waste. 7. Based upon the possible market development for products, overall pyroly economics to take account of treatment values of noncombustible or hazardous materials should be evaluated.

  • PDF