• Title/Summary/Keyword: Gas purge

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Aroma Characteristics of Tricholoma matsutake Mushrooms Collected from Eleven Major Sites in Korea (한국(韓國)의 11개(個) 주요(主要) 산지(産地)에서 채집(採集)한 송이(松栮)의 향기성분(香氣成分)에 관(關)한 연구(硏究))

  • Cho, Duck Hyun;Lee, Kyung Joon;Han, Sim Hee
    • Journal of Korean Society of Forest Science
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    • v.88 no.4
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    • pp.490-497
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    • 1999
  • The objectives of this study were to identify aroma characteristics of Tricholoma matsutake(S. Ito et Imai) Sing. growing in different geograghic ranges in South Korea. Mushrooms were collected from 11 major sites which included four sites(Bonghwa, Uljin, Goryung and Chungdo) in Kyongbuk Province, three sites(Changnyung, Hadong and Hamyang) in Kyongnam Province, two sites(Yangyang and Inje) in Kangwon Province, one site(Goisan) in Choongbuk Province, and one site(Namwon) in Chonbuk Province. One of three mushrooms from each site were used for measurements of aromatic characteristics. Aromatic compounds were identified using a dynamic headspace trap method at $40^{\circ}C$ and GC-MSD(gas chromatograph-mass spectrometric detector) method. A total of 25 aromatic compounds were identified. Large variations in the composition and amount of aromatic compounds were noticed. Major aroma compound was 1-octen-3-ol, while methyl cinnamate known as the major aroma compound in matsutake was not detected at all. The total amount of aromatic compounds was highest in Bonghwa, and decreased in the order of Chungdo, Inje, Hamyang, Uljin, and Yangyang. Based on the total amount, kinds and amounts of individual aromatic compounds, the mushrooms from 11 major sites were grouped into following four types : 1) Bongwha Type : the total amount of aromatic compounds was highest, with major compound being 3-methyl 1-butanol. 2) Hamyang Type including Chungdo, Yangyang and Inje : 1-octen-3-of comprised 2/3 of total aromatic compounds, with second major being 3-methyl butanal. 3) Uljin Type : 1-octen-3-ol comprised 94% of total aromatic compounds, with other compounds being almost nothing. 4) Goisan Type including Goryung, Namwon, Changnyung, and Hadong : the total amount of aromatic compounds was lower than other three types.

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Recent Progress in Air-Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2016 (설비공학 분야의 최근 연구 동향 : 2016년 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
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    • v.29 no.6
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    • pp.327-340
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    • 2017
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2016. 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 flow, heat and mass transfer, the reduction of pollutant exhaust gas, cooling and heating, the renewable energy system and the flow around buildings. CFD schemes were used more for all research areas. (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 of the long-term performance variation of the plate-type enthalpy exchange element made of paper, design optimization of an extruded-type cooling structure for reducing the weight of LED street lights, and hot plate welding of thermoplastic elastomer packing. In the area of pool boiling and condensing, the heat transfer characteristics of a finned-tube heat exchanger in a PCM (phase change material) thermal energy storage system, influence of flow boiling heat transfer on fouling phenomenon in nanofluids, and PCM at the simultaneous charging and discharging condition were studied. In the area of industrial heat exchangers, one-dimensional flow network model and porous-media model, and R245fa in a plate-shell heat exchanger were studied. (3) Various studies were published in the categories of refrigeration cycle, alternative refrigeration/energy system, system control. In the refrigeration cycle category, subjects include mobile cold storage heat exchanger, compressor reliability, indirect refrigeration system with $CO_2$ as secondary fluid, heat pump for fuel-cell vehicle, heat recovery from hybrid drier and heat exchangers with two-port and flat tubes. In the alternative refrigeration/energy system category, subjects include membrane module for dehumidification refrigeration, desiccant-assisted low-temperature drying, regenerative evaporative cooler and ejector-assisted multi-stage evaporation. In the system control category, subjects include multi-refrigeration system control, emergency cooling of data center and variable-speed compressor control. (4) In building mechanical system research fields, fifteenth 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, renewable energies, etc. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which could be help for improving 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 analyses of indoor thermal environments controlled by portable cooler, the effects of outdoor wind pressure in airflow at high-rise buildings, window air tightness related to the filling piece shapes, stack effect in core type's office building and the development of a movable drawer-type light shelf with adjustable depth of the reflector. The subjects of building energy were worked on the energy consumption analysis in office building, the prediction of exit air temperature of horizontal geothermal heat exchanger, LS-SVM based modeling of hot water supply load for district heating system, the energy saving effect of ERV system using night purge control method and the effect of strengthened insulation level to the building heating and cooling load.

Consideration about Ozone Generation in the Treatment Room While Treating a Patient (방사선 치료 시 치료실 내에서 발생하는 오존에 관한 고찰)

  • Kwak, Yong-Kuk;Yoon, Il-Kyu;Lee, Jae-Hee;Yoo, Suk-Hyun
    • The Journal of Korean Society for Radiation Therapy
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    • v.21 no.2
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    • pp.75-82
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    • 2009
  • Purpose: Measure the ozone level in the treatment room while treating a patient so want to know the degree of contamination caused by ozone occurrence. Materials and Methods: Use the linear accelerator (Clinac 21EX, Varian, USA) with the ozone meter (series-200, aeroQual, New Zealand) and water phantom (Wellhofer, IBA, Germany) is irradiated the radiation so that measured the ozone generation level according to MU, dose-rate, SSD, field size, energy, delay time and put the ozone meter in the treatment room actually while treating a patient so measured the daily ozone level variation. Results: While irradiating the radiation, degree of ozone contamination wasn't affected by the energy but mostly in case of electron beam, ozone level was higher than photon beam. The higher dose-rate (0.016~0.025 ppm/hr), the farther SSD (0.018~0.030 ppm/hr), the wider field sizes (0.016~0.025 ppm/hr), the more MU (0.018~0.046 ppm/hr), it occurred high ozone level. Ozone decrement according to delay time changed the background level (0.016 ppm/hr) after elapsed time of 10 minutes from irradiating radiation. And daily ozone occurrence level in the treatment room was below ozone standard level 0.1 ppm/hr (average:0.06 ppm/8 hr) but it could confirm that ozone generation level was included the level (max:0.038 ppm/hr) above 0.02 ppm/hr which patient could perceive. Conclusion: Through ozone level according to variation of certain conditions, actually in the treatment room ozone generation level didn't damaged to patients or workers. Commonly peoples think that ozone was harmful gas but it thought that small amount of ozone generation level while treating a patient was beneficial in the treatment room through air purge action of pathogenic germ or virus sterilization.

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