• Title/Summary/Keyword: Temperature rising

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Correlative Changes between Photosynthetic Activities and Chlorophyll Fluorescence in Wheat Chloroplasts Exposed to High Temperature

  • Young-Nam Hong
    • Journal of Plant Biology
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    • v.37 no.1
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    • pp.37-42
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    • 1994
  • Correlative changes between photosynthetic O2 exchange rates and room temperature Chl fluorescence were investigated in wheat (Triticum aestivum L.) chloroplasts treated with high temperature for 5 min. With increasing treatment temperature, photosynthetic O2 evolution rate mediated by PSII was decreased, showing 50% inhibition at 38$^{\circ}C$ (I50). But PSI activity measured by O2 uptake rates was stimulated as a function of increasing temperature. Dark level fluorescence (Fo)-temperature (T) analysis showed that fluorescence rising temperature (Tr), critical temperature (Tc), and peak temperature (Tp) was 38, 43, and 52$^{\circ}C$, respectively. Quenching analysis of Chl fluorescence showed that both the oxidized fraction of plastoquinone (qQ) and degree of thylakoid membrane energization (qNP) increased up to 4$0^{\circ}C$ and then declined dramatically. These results suggest that Tr is correlated with temperature showing a 50% of inhibition of photosynthesis and under mild high temperature stress, qNP is worth regarding as indicator for heat-induced damage of photosynthesis.

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A Study on Relations between Shape Factor and Temperature History of Steel of Composit Beam in Standard Fire under Same Thickness Condition of Spray-type Fire Resistant Materials (동일 내화뿜칠 피복조건에서 표준화재에 노출된 합성보의 강재 온도이력 및 단면형상계수와의 관계)

  • Yeo, In-Hwan;Cho, Kyung-Suk;Cho, Bum-Yean
    • Fire Science and Engineering
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    • v.26 no.6
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    • pp.72-77
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    • 2012
  • When the concrete and steel combined composite beam is exposed to high temperature, concrete could delay temperature rising of steel by covering or increase heat capacity of structural member. For becoming of structural reinforcing by unification between materials, fire resistance rate of composite beam would be higher than simple steel beam. The temperature rising of exposed steel of composite beam is directly related with section shape and exposure length of steel. In this study, fire resistant tests were carried out for composite beams and steel beam with same thickness of spray-type fire resistant materials in standard fire, and after that, temperature histories were analysed and compared with shape factor. The correlation between steel temperature and shape factor was showed very high. This result suggests that if it can be predict the comparative advantage of member by factor which cause the performance enhancement, it could be conclude that an Standard Accreditation method can be adjust to members without indivisual certifiicate of accreditation.

Changes of Phytic acid and Minerals by Heat Treatment in Korean Soybeans (한국산 대두의 열처리에 의한 피트산과 무기성분의 함량변화)

  • 김선경
    • Journal of the Korean Home Economics Association
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    • v.27 no.2
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    • pp.75-83
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    • 1989
  • In this study, effect of heat treatment on phytic acid, phosphorus compounds, and minerals in Korean soybean varieties was investigated. Results were summarized as follwo: 1. In the soybeans tested, protein content ranged from 34.6 to 44.6%, lipid content from 15.4 to 20.2%, fiber content from 4.8 to 6.1% and ash content from 4.5 to 5.9%. 2. Content range for phytic acid in soybean varieties was 1,300 to 1,542mg/100g and its mean was measured 1,392mg/100g. With increasing of the temperature, the phytic acid tends to be destroyed, especially at 6$0^{\circ}C$ the loss was averaged about 20%. 3. Total phosphorus content in soybean ranged from 607 to 681mg/100g and the decending order of phosphors content in soybean varieties was Millyang > Hwangkeum > Kwangkyo > Danyoup > Hill > Jangyoup. It was also destroyed with increasing temperature. 4. Phytate phosphorus content range in soybean was from 315.6 to 318.0mg/100g and decreased with increasing temperature. 5. Inorganic phosphorus content ranged from 95.5 to 110.0mg/100g and it was increased by temperature rising among soybean varieties. 6. Phytate phosphorus to total phosphorus ratio ranged from 5.2 to 5.7 and decreased by temperature rising. 7. The content of nonphytate phosphorus varied widely between soybean varieties and decreased with temperature increase. 8. The content of calcium, iron and magnesium ranged from 15.7 to 25.7mg/100g from 8.8 to 16.8mg/100g and from 121.9 to 143.6mg/100g respectively. The content of Mg showed small difference among soybean varieties. The change of mineral content with heat treatment in soybean did not give any meaningful change mineral content.

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Climate Change Assessment on Air Temperature over Han River and Imjin River Watersheds in Korea

  • Jang, S.;Hwang, M.
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.740-741
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    • 2015
  • the downscaled air temperature data over study region for the projected 2001 - 2099 period were then ensemble averaged, and the ensemble averages of 6 realizations were compared against the corresponding historical downscaled data for the 1961 - 2000 period in order to assess the impact of climate change on air temperature over study region by graphical, spatial and statistical methods. In order to evaluate the seasonal trends under future climate change conditions, the simulated annual, annual DJF (December-January-February), and annual JJA (June-July-August) mean air temperature for 5 watersheds during historical and future periods were evaluated. From the results, it is clear that there is a rising trend in the projected air temperature and future air temperature would be warmer by about 3 degrees Celsius toward the end of 21st century if the ensemble projections of air temperature become true. Spatial comparison of 30-year average annual mean air temperature between historical period (1970 - 1999) and ensemble average of 6-realization shows that air temperature is warmer toward end of 21st century compared to historical period.

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Synthesis of $CA_2$-based Clinker by Hydration-Burning Method (I) : Effects of Temperature on Synthesis (수화-소성법에 의한 $CA_2$클린커의 합성(I) : 합성에 미치는 온도의 영향)

  • 송태웅;한기성
    • Journal of the Korean Ceramic Society
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    • v.27 no.2
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    • pp.211-218
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    • 1990
  • CA2-based clinker with highly activated surface and hydraulic properties was synthesized at a comparatively lowr temperature than that of conventional synthesis by "hydration-burning method". This consists of calcining the mixture of CaCO3 and Al2O3 to obtain a primary clinker, hydrating the primary clinker and reburning the hydrates to obtain final clinker. Burning of primary clinker above 1200℃ was necessary to eliminate free CaO in it and to obtain it's solid hydrate. However, rising the burning temperature above 1300℃ is ineffective due to the decrease in hydraulic properties of the primary clinker with the temperature. Hydration of primary clinker at the elevated temperature(>35℃) was required to obtain the hydrate with more porous structure and final clinker with more active surface. CA2 was formed and increased with temperature at above 1150℃, finally became a primary phase of the final clinker. However, burning at the temperature above 1300℃ resulted in reverse effect on the hydraulic properties of the final clinker due to rapid decrease in it's surface area with the temperature.

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Evaulation of Adiabatic Temperature Rise for Concrete with Blast-Furnace Slag replacement (고로슬래그 미분말 치환율에 따른 콘크리트의 단열온도상승 평가)

  • Kim, Joo Hyung;Lee, Do Heun;Jung, Sang Hwa
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.8 no.1
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    • pp.18-24
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    • 2013
  • Recently, the interest is increasing about the eco-friendly concrete. Accordingly, the blast furnace slag(BFS), a by-product of industry is known for improving the durability through compaction in concrete and is expanding the use. The research about BFS in concrete be accomplished frequently. In this study, we should know the hydration characteristic of BFS concrete the through the adiabatic temperature rise test due to the replacement of a variety of BFS. In addition, we produced the regression analysis factors through the test result and analyzied the effect for the replacement of BFS. According to test results, the compressive strength showed a slight degradation or equal and the the adiabatic temperature rise figure and rising factors are went down for rising replacment of BFS. In the future, the study about the adiabatic temperature rise equation for the various replacement of BFS and binder is considered necessary.

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Effect of Post Heat Treatment on Bonding Interfaces in Ti/STS409L/Ti Cold Rolled Clad Materials (Ti/STS409L/Ti 냉연 클래드재의 접합계면특성에 미치는 후열처리의 영향)

  • Bae, D.S.;Kim, W.J.;Eom, S.C.;Park, J.H.;Lee, S.P.;Kim, M.J.;Kang, C.Y.
    • Transactions of Materials Processing
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    • v.20 no.2
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    • pp.140-145
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    • 2011
  • The aim of the present study is to derive optimized post heat treatment temperatures to get a proper formability for Ti/STS409L/Ti clad materials. These clad materials were fabricated by cold rolling followed by a post heat treatment process for 10 minutes at temperatures ranging from $500^{\circ}C$ to $850^{\circ}C$. The microstructure of the interface was observed using a Scanning Electron Microscope(SEM) and an Energy Dispersive X-ray Analyser(EDX) in order to investigate the effects of post heat treatment on the bonding properties of the Ti/STS409L/Ti clad materials. Diffusion bonding was observed at the interfaces with a diffusion layer thickness increasing with the post heat treatment temperature. The diffusion layer was composed of a type of(${\varepsilon}+{\zeta}$) intermetallic compound containing additional elements, namely, Fe, Ti and Ni. The micro Knoop hardness of the Ti/STS409L interfaces was found to increase with heat treatment up to $800^{\circ}C$ and then decrease for temperatures rising up to $850^{\circ}C$. The tensile strength was shown to decrease for heat treatment temperature increasing to $750^{\circ}C$ and then increase rapidly for temperature rising up to $850^{\circ}C$. A post heat treatment temperature range of $700{\sim}750^{\circ}C$ was found to optimize the formability of Ti/STS409L/Ti clad materials.

Thickening of Sludge from DAF process by Flotation; Application of Solid Flux Theory and Effective Factors (DAF 슬러지의 부상식 농축; 고형물 플럭스법 적용과 영향인자)

  • Park, Sangcheol;Han, Mooyoung;Dockko, Seok;Kwon, Soonbuhm
    • Journal of Korean Society of Water and Wastewater
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    • v.20 no.4
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    • pp.617-626
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    • 2006
  • Compared with the sludge from gravity sedimentation, it is difficult for operations to settle the sludge occurred from dissolved-air-flotation (DAF). Even though there are some problems in treating DAF sludge with conventional gravity thickeners, those has been used until now. In this study, Solid Flux theory for gravity thickening was applied to the Solid Flux of DAF sludge through flotation in order to develop new methodology for treatment of DAF sludge. Also, characteristics of DAF sludge were investigated. From the experiment results, it was revealed that the higher the polymer dosage, at fixed the solid concentration, the greater the rising velocity becomes. When we applied solid flux theory, the relationship, which is similar to that of gravity thickening, has been achieved. Also, we could find the proper polymer dosage from the rising velocity is about 50 mg/L. Consequently, the limiting solid flux can be derived from the relationship between the total solid flux and the withdrawal velocity of DAF sludge. Furthermore, the factors, such as solid concentrations, bubble volume, pH, zeta potential, and temperature, have effects on the flotation and sedimentation for DAF sludge treatment.

Study on the Application of Site for Exposure Type of Complex Waterproofing Method with Liquefied Waterproof using of Vertical Type Reinforcing Sheet Material Reinforced Sheet Rising System in the Roof Tops (돌기 시스템을 이용한 입체보강형시트의 옥상노출복합방수공법 적용에 관한 재료 및 공법적 연구)

  • Oh, Sang-Keun;Son, Mun-Se;Kim, Jin-Seong;Yeo, In-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2006.11a
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    • pp.17-20
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    • 2006
  • It often happen water leakage that roof membrane have a poor condition such as direct exposed to rain, ultraviolet lays, temperature change compare with other part of waterproofing. There are difficult to maintain the quality of waterproofing and durability due to use only few waterproofing materials in practical in spite of development and use the various waterproofing material as solution of these poor condition. Therefore, in this thesis, I would like to know the property to apply field and suggest other method to develop for this waterproofing method to adopt various field condition for roof tops, as searching exposed and complex waterproofing technology for roof tops which is reinforced sheet using rising system have a regular pitch, depth, space.

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Study on the Application of Site for Exposure Type of Complex Waterproofing Method with Liquefied Waterproof using of Vertical Type Reinforcing Sheet Material Reinforced Sheet Rising System in the Roof Tops (돌기 시스템을 이용한 입체보강형시트의 옥상노출복합방수공법 적용에 관한 재료 및 공법적 연구)

  • Oh, Sang-Keun;Son, Mum-Se;Kim, Jin-Seong;Yeo, In-Soo
    • Journal of the Korea Institute of Building Construction
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    • v.6 no.4 s.22
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    • pp.69-75
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    • 2006
  • It often happen water leakage that roof membrane have a poor condition such as direct exposed to rain, ultraviolet lays, temperature change compare with other part of waterproofing. There are difficult to maintain the quality of waterproofing and durability due to use only few waterproofing materials in practical in spite of development and use the various waterproofing material as solution of these poor condition. Therefore, in this thesis, I would like to know the property to apply field and suggest other method to develop for this waterproofing method to adopt various field condition for roof tops, as searching exposed and complex waterproofing technology for roof tops which is reinforced sheet using rising system have a regular pitch, depth, space.