This paper investigates the effect of prolonged high temperature exposure on concentric laminated Al2O3-ZrO2 composites. An ultrafine scale microstructure with a cellular 7 layer concentric lamination with unidirectional alignment was fabricated by a multi-pass extrusion method. Each laminate in the microstructure was 2-3μm thick. An alternate lamina was composed of 75%Al2O3-(25%m-ZrO2) and t-ZrO2 ceramics. The composite was sintered at 1500˚C and subjected to 1450˚C temperature for 24 hours to 72 hours. We investigated the effect of long time high temperature exposure on the generation of residual stress and grain growth and their effect on the overall stability of the composites. The residual stress development and its subsequent effect on the microstructure with the edge cracking behavior mechanism were investigated. The residual stress in the concentric laminated microstructure causes extensive micro cracks in the t-ZrO2 layer, despite the very thin laminate thickness. The material properties like Vickers hardness and fracture toughness were measured and evaluated along with the microstructure of the composites with prolonged high temperature exposure.

Reactive oxygen species (ROS) are produced by oxidative stresses which cause various chronic diseases such as diabetes and obesity. Ginseng (Panax ginseng C.A. Mayer) has been reported to contain various biological activities such as anti-cancer, anti-diabetic, neuroprotective, radioprotective, anti-amnestic and anti-aging effects. In this study, we investigated the effects of Panax ginseng, treated with high temperatures and high pressures, on oxidative stress in C2C12 myoblasts and 3T3-L1 adipocytes. Oxidative stress was induced in the C2C12 cells through the introduction of H₂O₂ (1 mM), and cells were then treated with various ginseng preparations: dried white ginseng (DG), steamed ginseng (SG) and high temperature and high pressure treated ginseng (HG). In addition, 3T3-L1 preadipocytes were treated with various ginsengs for up to 8 days following standard induction of differentiation. Our results show that HG treatment significantly protected oxidative stress in both cell lines and enhanced gene expression of antioxidant enzymes. Therefore, in this study, we investigated the protective effects of ginseng on the oxidative stress of adipocytes and muscle cells.

Chilling resistance at sowing is pre-requisite to avoid high temperature stress at terminal stage of spring planted maize crop. Seed priming offers promising solution to improve crop resistance against low or high temperature stress. Therefore, this study was conducted to evaluate the role of seed priming in improving the performance of spring planted maize under various sowing dates. Seeds of hybrid maize FH-810 were soaked in aerated solution of CaC}z (2.2%), moringa leaf extracts (MLE, 3.3%) and salicylic acid (SA, 50 mg L- 1 ) while dry and water soaked seeds (hydropriming) were used as controls. Both primed and untreated seeds were planted on 02 and 22 Feb, and 14 March. Late planted maize observed notable decline in mean emergence time than early planted crop owing to high temperature at planting. Both low and high temperature in early (02 Feb) and late (14 March) planted maize resulted in reduced seedling growth and tissue water status accompanied with elevated membrane electrolytes leakage. Moreover all the priming techniques improved the studied parameters of crop compared with control at all planting dates. Seed osmopriming with SA improved crop stress resistance by earlier emergence, increased seedling dry weight, tissue water status and improved membrane stability followed by osmopriming with CaC12.

The yield stress of stirred yogurt was measured by the vane viscometer at different pre-shearing conditions, such as pre-shear speed, pre-shear time, and wait time, and temperature (12-38oC). The yield stress ranged from ~17.6 to 10 Pa and from 34.2 to 11.9 Pa, depending on the pre-shearing conditions and temperature, respectively. The preshear speed and the wait time significantly affected the yield stress. The temperature dependence of the yield stress was described by the Eyring’s kinetic model. The linear function of the temperature on the yield stress was limited at the 22oC, and at the above 22oC, the yield stress was maintained to be a constant (~12.5 Pa).

오이묘가 저온피해를 입기 전, 후 토양수분조건과 몇 가지의 화학물질처리가 오이묘의 냉해 경감에 미치는 영향을 연구한 결과 토양수분 -0.3bar 적습상태에서 07:00시에 2℃로 저온처리를 했을 때, 생존율은 28.3%이었으나 -5.5bar에서는 83.3%로 높아져 토양수분이 건조하면 저온피해가 감소되었다. 그러나 18:00시에 저온처리하면 -0.3bar에서도 생존율은 87% 이상이었다. 토양수분이 건조하면 엽신의 ABA함량은 크게 증가되었다. 저온처리 전, 후 ABA의 토양 및 엽면처리는 오이묘의 생존율을 유의하게 증가시켰고 세포의 전해질 누출량도 현저하게 감소시켰으며, 수량의 감소를 경감시켰다. 또한 ABA 처리는 저온처리 후보다는 저온처리 전에, 엽면처리보다는 토양에 처리하는 것이 보다 효과적이었다. ABA(10-5M)와 더불어 요소(0.2%)와 KH2PO4의 엽면살포는 오이의 생장과 수량에 미치는 저온피해를 경감시키는데 효과적이었다.

In order to investigate 95% retained critical current of Bi-2223/Ag tapes under various stress-strain conditions, load cell attached tension and bending apparatus was used. The critical current of stress-strained tape was degraded below 95% retained critical current when tension and bending was simultaneously applied together. But only one of this tension or bending did not degrade the tape below 95% retained critical current. Deformation temperature was important to maintain the 95% retained Ic of Bi-2223/Ag tapes after bending or tension deformation because mechanical strength of tapes can be changed drastically between room temperature and 77 K.

This paper have performed to investigate the influence of certain parameters, including the boundary condition types, load ratios of the steel beams, and span/depth ratios of the beams itself on the structural behaviour of the steel beams at elevated temperatures. This paper is analysed the stress and vertical deflection at mid-span of the steel beams at elevated temperatures and also predicted 'failure' temperatures of the steel beams at elevated temperatures. Fire analysis used here is analysed by software VULCAN. Design examples are given to describe the structural behaviour of the steel beams at elevated temperatures.

여름철 자연조건에서 자라는 두릅나무과 식물 잎의 SOD활성과 광계II의 광화학적 효율의 차이를 분석하고 온도 스트레스와 paraquat의 영향을 조사하였다. 그 결과, 두릅나무과 식물 6종의 잎으로부터 총 8개의 superoxide dismutase(SOD) isoenzyme이 구분되었다. 그 중, 섬오갈피나무 (Acanthopanax koreanum)에서는 두릅나무과 식물에 공통적인 2개의 isoenzyme (SOD 4와 SOD 6)이 높은 활성으로

본(本) 실험(實驗)은 벼에 있어서 냉해(冷害)로 인(因)하여 매년(每年) 막대한 수확량(收穫量)의 감소(減少)를 생육시기별(生有時期別) 생장조절제(生長調節劑) 처리(處理)에 의한 재배적(栽培的) 방법(方法)을 통하여 그 피해(被害)를 감소(減少)시키고, 생장조절제(生長調節劑)에 대한 벼의 생리학적(生理學的) 활동(活動)과 농업적(農業的) 특성(特性), 수량구성요소(收量構成要素), 근활력(根活力), Chlorophyll 함량(含量) 등(等)의 변화(變化)를 통하여 수확량(收穫量)에 관계(關係)는 요소(要素)를 규명(糾明)하고, 벼 재배(栽培) 방법(力法)에 있어서 기초(基礎) 자료(資科)로써 이용(利用)하고자 실시(實施)하여 얻은 실험결과(實驗結果)는 다음과 같다. 저온(低溫)조건하에서 처리(處理)된 모든 생장조절제(生長調節劑)는 농도(濃度)에 관계(關係)없이 초장(草長), 분니 등의 벼 생유지연(生有遲延)을 다소 경감(輕減)시켰으며, 특(特)히 ABA는 농도(濃度)에 관계(關係)없이 초장(草長), 분니수등에 있어서 다른 생장조절제(生長調節劑)보다 그 효과(效果)가 두드러진 것을 알 수 있었다. 저온(低溫) 조건하(條件下)에서의 chlorophyll함량(含量)은 무처리구(無處理品)에 비하여 감소(減少)되나 식물생장조절제(植物生長調節劑)를 처리(處理)함으로써 Chlorophyll함량(含量)이 증가(增加)되었고, 또한 근활력(根活力)도 chlorophyll함량(含量)과 같은 경향(傾向)을 나타내었다. 생육(生有) 초기(初期)의 생장(生長) 조절제(調節劑)의 처리(處理)는 수량(收量) 구성요소(構成要素)의 감소(減少)를 경감(輕減)시켜 주었으며, 이는 수량(收量)에 직후(直接) 영향(影響)을 미쳐 냉해(冷害)로 인(因)한 수량감소(收量減少)를 경향(經向)시켰으며, 특(特)히 Abscissic acid처리(處理)의 효과(效果)는 뚜렷하게 나타났다. 그러나 저온하(低溫下)에서 수잉기때 생장조절제(生長調節劑) 처리(處理)는 영양생장(營養生長)에 별다른 효과(效果)를 나타내지 않았으나 수량구성요소(收量構成要素)에는 다소 영향(影響)을 미쳐 수량(收量)에 관여(關與)하는 것으로 나타났다. 저온조건하(低溫條件下)에서의 생장조절제(生長調節劑)의 처리(處理)는 처리시기(處理時期)에 따라 다소 차이(差異)가 있지만 수량손실(收量損失) 경감(輕減)에 크게 영향(影響)을 미친 것으로 사료(思料)된다.

Zr-4 used for a cladding and an end plug of reactor component has creep deformation under operation at high temperature. Creep is regarded as the time dependent deformation of a material under constant applied stress. Although the major source of the deformation of zirconium component in water-cooled reactors is irradiation creep, the thermal creep may give a rise to significant deformation in reactor component especially at relatively high temperatures and at various constant stresses, and therefore it must be predicted accurately. Stress relaxation is the time dependent change of stress at constant strain and it is a process related intimately to creep. In this paper, the creep behavior and stress relaxation of Zr-4 is examined at the temperature of 500℃ that is 40% of the absolute melting temperature of Zr-4 under the stress below yield stress and under the various constant strains. The results obtained are summarized as follows: 1) With an increase of stress, the steady state creep rate increases and the creep rupture time decreases. 2) The steady state creep rate ε(%/s) for the stress Σsub(c) (kgf/mm super(2)) of Zr-4 increases outstandingly. All the empirical equations computed for Zr-4 increases outstandingly. All the empirical equations computed for Zr-4 are in accord with Norton's model equation(ε=KΣ sub(c) super (n)). The constants of materials computed are as follows: K=3.9881×10 super(-5), n=1.9608 3) The rupture time T sub(r) (hr) decreases linearly with the increase of stress on the log-log scaled graph. The empirical equations computed for Zr-4 are in accord with Bailey's model equation (T sub(r)=K sub(1)Σsub(c) super(m)). The constants of materials computed are as follows: K sub(1)=1.2875×10 super(16), m=-3.467 4) It seems clear that the strain could be quantitatively dependent on the high temperature creep properties such as creep stress, rupture time, steady state creep rate and total creep rate. It is found that these relationships are linear on the log-log graph. 5) In stress relaxation test, as the critical constant strain that can be allowed to the specimen is larger, stress relaxation becomes more rapid, and as the constant strain is smaller, the stress relaxation becomes slower.

Background : Due to changes in climate and cultivation conditions, the growth monitoring is an essential factor in improving crop productivity. With the recent development of image analysis technology incorporating ICT, it has become possible to constantly monitor the crop growth. As a medicinal crop specialized in Gyeongsangbuk-do, Korea, Cnidium officinale Makino was examined for the possibility of growth diagnosis through image analysis for stable production. Methods and Results : The IP camera was installed at 2.5 m height in experiment field. The RGB image of every 06:00 was captured from July 1 to July 30 and used for analysis. The captured images were analyzed using the image analysis tool, Image J. The greeness was estimated by the average value of the green histogram. The canopy size was determined by the color range (red: 0-255, green: mean value-255, blue: 0-255) and was calculated as the ratio of pixels number of the entire image to those of the selected area. The growth temperature during investigation period was measured by Hobo MX2300. High temperature, excess of 28℃, was compared to stress response such as decrement of canopy size. The greeness and the canopy size are respectively represented by the quadratic function greeness = -0.0722GD2 + 6248.9GD – 1e + 08 (GD, growing day; R2 = 0.46) and canopy size = -0.0462GD2 + 3996.7GD – 9e + 07 (R2 = 0.93). From July 11, it began to exceed the growth limit temperature of 28℃, and the canopy size began to decrease from this period. Between the canopy size (C) and the accumulated temperature exceeding 28℃, there was a negative correlation, C = -0.13ATEC + 56.75 (R2 = 0.87) during the decreasing period. Conclusion : Extraction of color information in Cnidium officinale Makino using RGB image should be preceded by standardized setting, but it is considered to be useful tool for analyzing the change of quantitative characteristics over time. In the future, it is necessary to make a comparative study with the actual growth rate in the image diagnosis.

The aim of study is to contribute to this knowledge-base by investigating the respiratory function, the metabolic rate and the difference of physiological responses un-der low water temperature (20℃→15℃) stress be-tween diploid and triploid far eastern catfish, Silurus asotus. During the 48 hrs of water temperature stress exposure time, the respiratory frequencies, CO₂ and NH₄+ concentrations of diploid had higher values than those of triploid (p<0.05). However, pH of triploid was higher than those of diploid (p<0.05), and oxygen consumption rate was not different between diploid and triploid (p>0.05). The level of plasma cortisol and plasma glucose of triploid was lower than those of the diploid (p<0.05). However, in case of lactic acid, there were not significant between triploid and diploid (p>0.05). These results suggest that diploid was more sensitive for low water temperature stress response than triploid in this species.

Data from the strain gauge and temperature sensor through the analysis in the future appear to be capable of vertical construction step analysis Behavior of Concrete Box Girder is judged to be high usability.

Asphalt material is visco-elastic material, which is sensitive to temperature and such phenomenon can result in affect to super-structure of concrete trackbed systems under various temperature loads. Consequently, the key objective of this research is to evaluate the performance related to stress changes of wide sleepers on asphalt-concrete trackbed systems corresponding to temperature changes. The range of temperature to represent the season is 60℃∼-10℃ and the numerical analysis was conducted in ABAQUS

This study was conducted to investigate plant body temperature response of soybean (Glycine max) to saline stress. Two-weeks-old seedlings of soybean in V1 growth stage were treated with 0, 10, 20, 40, 80 and 160 mM of NaCl for salt stress. Thermal images acquired using Flir T-420 (US) were obtained at 4 days after treatment. Soybean leaf temperature increased with increasing NaCl concentration, resulting in significant positive correlation between soybean leaf temperature and stress intensity (P < 0.01). Leaf temperature of soybean was significantly different at 160 mM of NaCl, where no visual symptom was observed. Therefore, soybean leaf temperature can be used for evaluating the response of soybean to salt stress as a non-destructive and phenomic parameter. Non-destructive diagnosis of soybean leaf temperature may be a key parameter in a high throughput screening (HTS) system in breeding program for salt stress tolerance soybean cultivars.