• Title/Summary/Keyword: 온도 저하율

Search Result 398, Processing Time 0.032 seconds

The Characteristics of TPH Removals by Microwave Radiation for Diesel Contaminated Soil (디젤오염토양 마이크로파 처리 시 TPH의 제거 특성)

  • Jeong, Seung-Woo;Lee, Tae-Jin
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.35 no.11
    • /
    • pp.776-780
    • /
    • 2013
  • TPH degrdation patterns in diesel contaminated soil was investigated with microwave radiation. When microwave radiation on the soil was applied, temperature increment of the aridic soil was quite low, but temperature in the moist soil was dramatically increased even if short period of running time. Up to 20% of the moisture content, the higher moisture content has more increment of temperature, whereas over 20% of the moisture content, temperature in the soil was rather decreased. when 100~700 W power of microwave radiation was applied into the contaminated soil, a lot of TPH removals was observed under 300 W, but negligible increment of TPH removal was detected over 300 W. 60% of TPH removal was achieved with initial 20% moisture content and microwave radiation. Additional 25% removal was accomplished when moisture content was kept constant during radiation period. It indicated that maintaining of constant moisture is an important factor for TPH removal with microwave radiation because moisture and temperature in the soil are decreased with reaction time.

A Study on Properties of Early Strength Development of the Concrete (콘크리트의 조기강도 발현특성에 관한 연구)

  • Kang, Chang-Woon;Lee, Jae-Sam;Kim, Jung-Sik;Sung, Yong-Hwan;Ryu, Deug-Hyun
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2008.11a
    • /
    • pp.541-544
    • /
    • 2008
  • Recently, due to the increase of high-rise buildings construction, many researches for making harden of concrete earlier and remove of forms faster are being performed to reduce construction period. The purpose of this study is to analysis which mixing condition and curing temperature of early strength concrete. Porperties of concrete by the different factors, such as the type of active admixtures, mineral admixtures, curing temperature, the amount of binder, etc. Through the test of concrete using the different type of admixture, PC type was more excellent than PNS type admixture. The concrete Strength remarkably will be able to confirm that decreases from temperature below 12$^{\circ}C$.

  • PDF

Inhibition of Floral Induction and Variation of Yield in Angelica gigas Nagai (참당귀의 화성억제와 수량변화)

  • 조선행;김기준
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.38 no.2
    • /
    • pp.151-158
    • /
    • 1993
  • Since the inhibition of floral induction was considered to be an important subject to get high yield of Angelica gigas, the effects of low temperature, daylengh and shading were investigated in this study. The yield of A. gigas root grown by inhibition of floral induction was compared with the yield obtained by traditional cultivation method. When the seedings were exposed to the natural low air temperature condition until late of November, the plants which had 6 to 8 leaves showed vernalizing effect, and when the low temperature treatment was prolonged until mid of January, 4 to 5 leaf plants showed vernalizing effect. But 2 to 3 leaf plants did not show vernalizing effect regardless of the length of chilling treatment. The effectiveness of exposure to low temperature was markedly dependent upon the age of plants. In the artificial low temperature treatment the range of temperature varied with plant age. Vernalizing effect at 1,5 and 9$^{\circ}C$ of temperature did not show 3,5,6 leaf plants, respectively. The bolting percent in 8 leaf plant at 1,5 and 9$^{\circ}C$ for 8 weeks decreased by 80,45 and 5%, respectively. As daylength became longer, the bolting percent of A. gigas was increased. plants which were grown in the full sunlight showed the highest value in bolting percent, and the bolting percent was not decreased significantly with changing from full sunlight to 50% shading. When A. gigas were grown by the inhibition of floral induction, dry root weight per l0a showed the greatest value in 3 year old plant which 3.6 and 2.4 times higher than that of 1 and 2 year old plant, respectively. The yield of root was increased by 73.7% in 2 year old plant and 159.6% in 3 year old plant compared with the yield obtained by traditional cultivation method.

  • PDF

Effect of temperature on photosynthetic capacity and influence of harvesting time on quality of Salvia miltiorrhiza Bunge (온도에 따른 단삼의 광합성 특성 및 수확시기가 품질에 미치는 영향)

  • Seo, Young-Jin;Kim, Jong-Su;Kim, Sun-Hwa;Kim, Mi-Yeon;Jeong, Yong-Jin;Seong, Gi-Un;Chung, Shin-Kyo
    • Food Science and Preservation
    • /
    • v.22 no.6
    • /
    • pp.804-810
    • /
    • 2015
  • Salvia miltiorrhiza has been used for treating heart and liver disease. In the present study, the influences of temperature on photosynthetical capacity of S. miltiorrhiza under controlled cultivation environment using growth chamber were investigated because of providing information about growth and secondary metabolite synthesis. And effect of harvesting time on growth properties and constituents such as salvianolic acid B, cryptotanshinone, tanshinone I, tanshinone IIA were evaluated. Maximum photosynthesis rate ($5.102{\mu}mol\;CO2/m2/s$) and net apparent quantum yield ($0.147{\mu}mol\;CO2/m2/s$), stomatal conductance (0.035 mmol/m2/s) and water use efficiency ($7.108{\mu}mol\;CO2/mmol\;H2O$) was highest at $20^{\circ}C$. Results of chlorophyll fluorescence showed that elevated temperature had contributed to reduce a quantum yield and electron flux in photosystem. This result demonstrated that favorable temperature condition was determined at $20^{\circ}C$. Contents of salvianolic acid B, cryptotanshinone, tanshinone I and tanshinone IIA was highest in root sample harvested at 20 March, whereas growth and yield of S. miltiorrhiza had no significant differences with harvesting time. Therefore, this study shows that temperature play an important role in photosynthetic activity and harvesting time have influence upon accumulation of constituents in root of S. miltiorrhiza.

Changes in Seed Vigour of Sweet and Super Sweet Corn Hybrids as Affected by Storage Conditions (단옥수수와 초당옥수수의 저장조건에 따른 종자 활력변화)

  • Lee Suk-Soon;Yun Sang-Hee;Yang Seung-Kyu;Hong Seung-Beom
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.51 no.5
    • /
    • pp.432-439
    • /
    • 2006
  • An experiment was conducted to characterize the seed vigour of sweet (su) and super sweet (sh2) corn seeds stored at different temperatures and relative humidities (RH). Hybrid seeds of Early Sunglow ${\times}$ Golden Cross Bantam 70 (su) and Xtrasweet 82 ${\times}$ Fortune (sh2) were stored at different temperatures ($5\;and\;15^{\circ}C$) and RH(70 and 85%) for 10 months. Results of the experiment show that seed deterioration of super sweet corn was much faster than that of sweet corn under all storage conditions. Germination rate of sweet corn seeds at $25^{\circ}C$ and emergence rate in cold test showed similar patterns. Emergence rate of super sweet corn in cold test was significantly lower than the germination rate at $25^{\circ}C$. Germination rate of both sweet and super sweet corns was positively correlated to the emergence rate in cold test, but the correlation coefficient of super sweet corn was much lower compared to the sweet corn. This implies that the viability of super sweet corn seeds should be tested in the cold test to estimate field emergence rate. Seeds of sweet corn could be stored for 5 months under all storage conditions without significant seed deterioration, while those of super sweet corn should be stored at low temperature and RH. The emergence rate of sweet corn in cold test was not correlated to the leakage of total sugars, electrolytes or ${\alpha}-amylase$ activity, while that of super sweet com was positively correlated to the ${\alpha}-amylase$ activity, negatively correlated to the leakage of electrolytes, and was not correlated to the leakage of total sugars.

Degradation Pattern and Rate of Some Pesticides in Soils -Part I. Degradation Pattern and Rate of Parathion in Soils- (토양처리(土壤處理) 농약제(農藥劑)의 분해율(分解率)에 관한 연구(硏究) -제1보(第一報). Parathion의 토양중(土壤中) 분해(分解)에 대하여-)

  • Lim, Sun-Uk;Kang, Kyu-Yung;Choi, Yong-Lak
    • Applied Biological Chemistry
    • /
    • v.26 no.4
    • /
    • pp.239-247
    • /
    • 1983
  • The effects of some soil conditions on the degradation rate and decomposing pattern of parathion were investigated and the obtained results are summarized as follows: Parathion degraded more rapidly in flooded soils than in non-flooded, in wet soils than in dry soils under non-flooded soils. The degradation rates in paddy and upland soils increased at high temperature than low temperature, higher pesticide concentration than low concentration and higher soil pH level. Parathion in paddy and upland soils was more persistent under soil sterilization than under non-sterilization and degraded rapidly in glucose application. Parathion was more persistent in upland soils than paddy soils under several factors described above. The metabolites identified from the paddy and upland soils by TLC include para-oxon (Rf 0.5), aminoparathion(Rf 0.27), p-nitrophenol(Rf 0.2), p-aminophenol(Rf 0.15). Soil enzyme, acid phosphatase activities decreased more at flooded soils than non-flooded, higher pesticide concentration than low concentration and higher soil pH level and the activity in glucose application was increased. Soil enzymes, urease and dehydrogenase activity decreased more at higher pesticide concentration than low concentration. Comparing with soil enzyme activity in paddy and upland soil, the former was higher than the latter.

  • PDF

A Development of Cholesterol Removed Cheese (콜레스테롤을 제거한 치즈의 개발에 관한 연구)

  • 정청송
    • Proceedings of the Korea Hospitality Industry Research Society Conference
    • /
    • 2002.11a
    • /
    • pp.83-98
    • /
    • 2002
  • The old testament of the Bible has written the milk and curd. God said, I will ive you to how the milk and honey. The present study was designed to examine the effects of different homogenization pressure, homogenization temperature and $\beta$-cyclodextrin concentration on cholesterol removal rate of cheese, and to optimize the factors of cheese manufacture Process. In addition, the characteristics from cholesterol removed cheese and control are compared in the rheological and ensory analysis. The optimized process condition for cholesterol removal was for homogenization pressure, 74$^{\circ}C$ for homogenization temperature and 2% for $\beta$-cyclodextrin concentration, it showed 875% of the highest cholesterol removal rate in milk. Therefore, manufacture conditions of cholesterol removed cheese were chosen 74$^{\circ}C$ for homogenization temperature, for homogenization pressure, and I or 2% for $\beta$-cyclodextrin concentration. Cholesterol removed cheese and control were compared with yield, cholesterol removal, meltability, stretchability, textural properties and sensory analysis. Cholesterol content of control cheese containing 23.8% milk fat was cheese made from milk treated with 2% $\beta$-cyclodextrin and homogenization pressure was cholesterol removal. Yield of cholesterol removed cheese. As the homogenization pressure increased, oiling off reduced with showed better surface appearance. Stretchability of cholesterol removed cheese was lower 5~10cm than over 30cm of control. Meltability of cholesterol removed cheese also was lower than control. The hardness, gumminess, chewiness reduced to respectively. In the result of sensory analysis, treatment of homogenization for cholesterol removed cheese improved appearance and flavor, however texture fell. In addition, the resent result of the study indicated that about 75% of cholesterol in cheese could be removed, and the possibility of development of cholesterol removed cheese was observed. We have hope to research manufacture cheese global wide.

  • PDF

Char Oxidation Characteristics of High Ash Coal in Drop Tube Furnace (고회분탄의 촤 산화 반응 특성 연구)

  • An, Ke-Ju;Lee, Byoung-Hwa;Kim, Sang-In;Kim, Man-Cheol;Kim, Seung-Mo;Jeon, Chung-Hwan
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.37 no.4
    • /
    • pp.405-413
    • /
    • 2013
  • The char oxidation characteristics of high ash coal were experimentally investigated at several temperatures (from 900 to $1300^{\circ}C$) for 4 types of coals (Gunvor, Glencore, Noble, and ECM) under atmospheric pressure in a drop tube furnace (DTF). The char reaction rate was calculated from the exhaust gas concentrations (CO and $CO_2$) using FT-IR, and the particle temperature was measured using the two-color method. In addition, the activation energy and pre-exponential factor for high ash coal char were calculated based on the Arrhenius equation. The results show that as the ash content increases, the particle temperature and area reactivity decreases. This is because in high ash coal, the large heat capacity of the ash, ash vaporization, and relatively low fixed carbon content of ash suppress combustibility during char oxidation. As a result, the higher ash content of coal leads to high activation energy.

Fundamental Study on the Strength and Heat Transferring Charcteristic of Cement Composite with Waste CNT (폐CNT를 혼입한 시멘트 복합체의 강도 및 열전달 특성에 대한 기초적 연구)

  • Koo, Hounchul;Kim, Woon-Hak;Oh, Hongseob
    • Journal of the Korean Recycled Construction Resources Institute
    • /
    • v.10 no.1
    • /
    • pp.66-73
    • /
    • 2022
  • The purpose of this study was to develop self-heating concrete by utilizing the conduction resistance of concrete in order to reduce the risk of occurrence of black ice in the concrete pavement in winter and to prevent damage caused by freez-thawing effect. For this purpose, it was attempted to evaluate the strength and temperature exothermic characteristics using powder and liquid waste CNTs and a waste cathode agent as a conduction promotion. It was analyzed that liquid waste CNT had an effective dispersion degree in the mortar and a small decrease in strength occurred. In addition, DC 24 V was supplied by applying steel mesh, copper foil and copper wire to the mortar as electrodes, and the temperature change characteristics according to the mixing ratio of spent CNTs, anodes and carbon fibers were evaluated. In addition, by evaluating the temperature characteristics according to the electrode spacing from the selected optimal mixture, it was confirmed that it had sufficient heating characteristics up to an electrode spacing of 100 mm up to AC 50 V.

Nondestructive Vigor Test of Seed (비파괴적 방법에 의한 종자의 활력 검정)

  • 이석순;홍승범
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.40 no.3
    • /
    • pp.314-321
    • /
    • 1995
  • Experiments were conducted to obtain information on separation of nonviable seeds from seed lots of rape, Chinese cabbage and radish, by nondestrutive ways. Seeds were artificially aged at 90% relative humidity(RH) and 45$^{\circ}C$ to get different seed qualities. Large amounts of amino acids, proteins and sinapine were leaked from the dead seeds into water in the course of 4~8 hours soaking, while high quality seeds did not leak in all crops. Percentage of normal seedlings from nonfluorescent cellulose coated seeds of rape, Chinese cabbage and radish under ultraviolet light was 96, 96 and 74%, while that of fluorescent seeds was 8, 9 and 1%, respectively. Cellulose coating and storage of Chinese cabbage and rape seeds at 60 and 75% RH for 3 months and 90% RH for 2 months did not deteriorate seed quality. But percentage of normal seedlings from nonfluorescent radish seeds stored at 60, 75 and 90% RHs for 3 months was 63, 64 and 2%, respectively.

  • PDF