• 한국생물환경조절학회:학술대회논문집
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• 한국생물환경조절학회 2001년도 봄 학술발표논문집
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• pp.43-44
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• 2001

Recently the sawdust culture of Lentinus edodes(Berk.) has been gradually extended replacing the log cultivation in Korea. It is indeed able to reduce the use of log and cultivation period in controlled facilities, but is not yet able to produce the high-quality mushroom. The objectives of this study were to examine the effects of low and alternated temperature treatments during the fruiting period on the quality of oak mushroom. At low temperature treatments of 1$^{\circ}C$ and 10$^{\circ}C$, the crack, lightness, hardness, and other characteristics for the high-quality oak mushroom were not improved. However, the crack, brightness, and hardness of cap were increased at alternated temperatures of 5-10$^{\circ}C$ than the other temperature treatments. In conclusion, the alternated temperature treatments were more effective than the low temperature treatment for improving the indices of high-quality oak mushroom such as the crack, brightness and hardness of cap.

• 한국환경과학회지
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• 제23권5호
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• pp.781-786
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• 2014

Growth and physiological disorders caused by abnormally low temperatures were evaluated in pepper, an important field crop in Korea. In addition, the effects of chemical treatment using glutamine was verified on minimizing the damages by low temperature. The growth of pepper plants in stem length and diameter was suppressed as the temperature decreased from $25^{\circ}C$, and the suppression level was the highest for plants grown for 90 days at $20^{\circ}C$. However, root growth was not affected by the different temperatures. The number of leaf and leaf area decreased at the temperatures below $25^{\circ}C$, an optimum temperature for growth. Fresh weight and dry weight decreased for plants grown at $20^{\circ}C$. Pepper fruit yield also decreased by 11% at $20^{\circ}C$ in comparison to $25^{\circ}C$. Falling blossom rate was different depending on the growth temperature, and the rate was 27.2% at $25^{\circ}C$, 35.2% at $22.5^{\circ}C$, and 41.0% at $20^{\circ}C$, indicating that falling blossom rate increased as temperature decreased. Different growth temperatures did not affected on the level of symptom of calcium deficiency and Phytopathora blight. Falling blossom was severe at abnormally low temperature of $20^{\circ}C$, but the treatment of glutamine reduced falling blossom rate and increased the yield by 7.0% as compared to control. The optimum concentration of glutamine treatment was 10 mg/L for yields.

• 한국작물학회지
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• 제38권2호
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• pp.151-158
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• 1993

참당귀(Angelica gigas Nakai)의 재배에서 크게 문제가 되는 화성억제를 위해 온도, 일장 및 광도가 화아분화와 추대에 미치는 영향을 조사했으며, 관행재배와 화성을 추제시켜 재배생산된 근의 수량을 조사하여 연근별로 비교하였다. 본 시험에서 얻어진 결과를 요약하면 다음과 같다. 1. 자연온도처리(대조구)의 경우 11월 20일 처리구의 본엽 6～8매부터 화아분화 및 추대가 시작되어 처리기간이 길어질수록 추대율이 증가하다가 익년 1월 11일 이후부터는 변화가 없었으며 본엽 2～3매 는 어떤 구에서도 추대가 전혀 없었다. 2. 인공온도처리의 경우 처리온도가 높아질수록 주온감응한계엽령이 증가하였다. 즉, 1$^{\circ}C$, 5$^{\circ}C$, 9$^{\circ}C$ 처리구 각각 3매, 5매, 6매가지는 전혀 추대가 없었으며 8주 8매구에서도 1$^{\circ}C$에서 80%, 5$^{\circ}C$에서 45%, 9$^{\circ}C$에서 5%로 추대율이 저하하였다. 3. 참당귀의 추대율은 일장이 길어질수록 증가하였고, 광도시험에 있어서는 자연광구에서 가장 높았으나 광도가 감소할수록 점차 줄었으나 차광 50%까지 유의성이 인정되지 않았다. 4. 화도를 억제시켜 재배했을 때 10a당 건근중은 3년근이 가장 많았고 1ㆍ2년근에 비해 각각 3.6배, 2.4배 증수되었으며, 관행재배보다 2년근은 73.7%, 3년근은 159.6% 증수효과가 있었다.

• 한국물환경학회지
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• 제22권2호
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• pp.258-263
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• 2006

ANAMMOX (Anaerobic ammonium oxidation) reactor, which was cultivated ANAMMOX bacteria in mesophilic condition ($35^{\circ}C$), was operated to investigate the effects of temperature. In $20{\sim}30^{\circ}C$ of operation condition, which was assumed as field-temperature, total N removal and $NH_4-N$ removal rate were declined from about 2.50 and $1.27kg\;N/{m^3}_{reactor}-day$ (0.06 and 0.03 kg N/kgVSS/day) to 1.62 and $0.41kg\;N/{m^3}_{reactor}-day$ (0.04 and 0.01 kg N/kgVSS/day), In this range of temperature, ANAMMOX had very low activities but acid fermentation bacteria and denitrifiers, which were competitors of substrates, had high activities relatively. Though operation temperature was higher than inhibition condition for two months, ANAMMOX activities could not been recovered once they were inhibited by low temperature. This fact was resulted from very slow doubling time of ANAMMOX bacteria. This study shows that maintenance device of optimal temperature is necessary required in field application of ANAMMOX.

• 열처리공학회지
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• 제23권1호
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• pp.3-9
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• 2010

Titanium and its alloys were brazed in the range of $850-950^{\circ}C$ within 10 min. of brazing time using expensive infra red or other heating methods. However, brazing time needs to be extended to get temperature-uniformity for mass production by using continuous belt type furnace or high vacuum furnace with low heating rate. This study examined effects of holding temperature for 60 min, on microstructure and mechanical properties of titanium alloys. Mechanical properties of titanium alloys were drastically deteriorated with increasing holding temperature followed by grain growth. Maximum holding temperatures for CP (commercial pure) titanium and Ti-6Al-4V were confirmed as $800^{\circ}C$ and $850^{\circ}C$, respectively. Both titanium alloys were successfully brazed at $800^{\circ}C$ for 60 min. with the level of base metal strengths by using Zr based filler metal, $Zr_{54}Ti_{22}Ni_{16}Cu_8$.

• 상하수도학회지
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• 제10권4호
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• pp.45-54
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• 1996

Effects of temperature on the efficiency of the Upflow Anaerobic Sludge Blanket(UASB) process for treatment of wastewater from a starch and related products manufacturing industry were investigated using laboratory scale reactors equipped with two types of Gas-Solid Separator(GSS). Both fresh digested sludge and granular sludge stored nearly for one year at room temperature were good as a seeding material. The reactors seeded with aged granular sludge showed slow start-up, however, lowered activity at the initial period was recovered gradually. The GSS with an inner cylinder was proved to be effective in liquid-solid separation compared to the conventional type. Although the rate of organic removal and gas production per unit volatile suspended solids in the reactor reduced significantly as the temperature varied from 35 to $20^{\circ}C$, possibility of operation at low temperatures was shown as a result of gradual buildup of volatile suspended solids in the bed. Stable operation with a reduced efficiency was possible at a COD loading of $5-8kg/m^3/day$ at a temperature as low as $20^{\circ}C$.

• 한국식품저장유통학회지
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• 제23권5호
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• pp.666-672
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• 2016

본 실험은 약주 제조 과정에서 효모와 발효온도에 따른 약주의 품질을 분석하였다. 약주의 이화학적 특성(pH, 총산, 에탄올, 유리 아미노산, 유기산, 향기 성분)을 조사하였다. 약주는 증자된 멥쌀에 입국과 효모를 넣고 각기 다른 온도($15^{\circ}C$, $20^{\circ}C$, $25^{\circ}C$)에서 20일간 발효하였다. $20^{\circ}C$에서 발효한 S. cerevisiae Y297 처리구는 다른 처리구에 비해 높은 알코올 생산성(17.9%)을 보였다. 온도관련 항체인 HSP104를 이용하여 면역반응을 확인한 결과, S. cerevisiae Y297 처리구는 대조구에 비해 저온에서 HSP104 단백질의 발현율이 높게 나타났다. 유기산 분석 결과, 대조구의 $25^{\circ}C$에서 젖산의 함량이 높게 분석되었다. 유리아미노산 분석 결과, 저온에서 S. cerevisiae Y297 처리구는 대조구에 비해 높은 필수 아미노산량을 확인할 수 있었다. 이러한 결과들을 통해 S. cerevisiae Y297 균주가 저온에서 제조하는 약주 생산에 사용할 수 있는 효모로써의 가능성을 확인할 수 있었다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2004년도 제29회 KOSCI SYMPOSIUM 논문집
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• pp.225-230
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• 2004

Volatile organic compounds (VOCs) are low calorific value gases (LCVG) emitted from chemical processes such as painting booth, dye works and drying processes etc. Characteristics of VOCs are low calorific values less than 150 kcal/$m^3$, high activation energy for ignition and low energy output. These characteristics usually make combustion unstable and its treatment processes needs high-energy consumption, The cyclone combustion system is suitable for LCVG burning because it can recirculate energy through a high swirling flow to supply the activation energy for ignition, increases energy density to make a combustion temperature higher than usual swirl combustor and also increases mixing intensity, This research was conducted to develop optimized cyclone combustion system for thermal oxidation of VOCs. This research was executed to establish the effect of swirl number with respect to the combustion temperature and composition of exhausted gas in the specific combustor design.

• Agricultural and Biosystems Engineering
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• 제2권2호
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• pp.75-80
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• 2001

This paper describes method to diagnose abiotic stresses such ad low root temperature, low light intensity and high salinity in cucumber plants with several physiological instruments. The stresses could be detected by measuring and analyzing the differences in chlorophyll content, temperature difference between leaf and atmosphere and light absorptance at wavelengths of 480, 560, 710, 1420 and 1650nm. It was concluded that the stresses could be first diagnosed from the 3rd to 10th day after treatment and the overall accuracy of diagnosis was estimated between 25 and 75%. near-infrared spectrometer showed better and earlier detection than the other instruments investigated.

• Journal of Plant Biology
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• 제17권4호
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• pp.31-37
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• 1974

Seedlings of Nongbaek representing strong cold tolerant variety of rice plant, Jinheung of medium variety and Tongil of weak variety were used respectively for the present study. These seedlings were water cultured in phytotron which maintained at the daytime and night temperature of 30-$25^{\circ}C$, 20-2$0^{\circ}C$, 20-15$^{\circ}C$ and 15-1$0^{\circ}C$. The growth rate of plant height, tillering rate, increase in dry weight and absorption pattern of important mineral nutrients at their early growth stage under each temperature conditions were observed. Generally, it appeared that Nongbaek was more active in the growth of plant height than Jinheung, and Jinheung was more active than Tongil under low temperature condition. The tillering rate of these three varieties was equally rapid while it was decreased in the order of weak cold tolerant variety, such as Tongil, Jinheung and Nongbaek as the temperature declined gradually. The dry weigh tincreasing curve showed almost the same pattern in the varieties at the treatment of each temperature. Under low temperature conditions, Nongbaek showed higher absorption rate of N per dry weight and higher absorption amount of per plant body, Jinheung followed and Tongil was the lowest. The absorption amount of P2O5 increased in the top part compared with the roots as temperature rose and decreased as temperature declined. There seemed to be no difference of absorption among the varieties which have different cold tolerance each other. Under low temperature the absorption rate of K per dry weight was high, as a whole, especially Nongbaek was markedly higher than the other two. The absorption rate of Ca, Mg and Fe was also equally high in all varieties under low temperature and Nongbaek showed a more absorptive tendency in the absorption amount under low temperature.