• 분석과학
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• 제12권1호
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• pp.75-79
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• 1999

봄무우 유식물의 자엽과 하배축에서 저온처리동안 변화하는 polyamine(PA)의 농도를 분석하고, PA이 저온 스트레스와 관련이 있는지를 분석하였다. 자엽에서 저온 스트레스동안 putrescine(PUT)의 농도가 증가되었고, 전반적으로 PUT와 spermidine(SPD) 농도의 변화가 심하였다. 따라서 PUT와 SPD는 저온 스트레스의 조건하에서 합성되거나 또는 유리된 것이다. 그러나 spermine(SPM)의 농도에는 거의 변화가 없었다. 하배축의 대조구에는 SPD만이 존재하고, 저온 스트레스를 주면, 유리된 PA의 농다가 증가되었고, 지속된 저온 스트레스동안 PA의 농도가 급속히 감소되었다. 하배축은 일반적으로 저온처리에 매우 예민성을 나타내는 것으로보아, 자엽과 비교해서 세포내에 PA의 농도가 낮기 때문인 것으로 판단된다. 자엽에서 PUT과 SPD가 저온 스트레스의 저항력에 관여하고, 하배축에서는 PA이 저온 스트레스에 대한 저항력의 증대와 아무 관련이 없는 것으로 사료된다. 이상의 결과로 PUT와 SPD는 저온 스트레스에 대항하여 저항력을 증대시키는 것으로 판단된다.

• 한국육종학회지
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• 제41권2호
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• pp.73-83
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• 2009

To investigate genes related to vernalization and cold- resistance in barley (Hordeum vulgare L. cv. Nagaoka), differentially expressed genes were identified from cold-resistant barley leaves with suppression subtractive hybridization (SSH) and Northern blot analyses. The nucleotide and the deduced amino acid sequences of the putative gene products were compared. The bvrn-7 showed high homology(84%) with gene related to vernalization, and the bvrn-3, bvrn-12, bvrn-28, bvrn-29 and bvrn-36 related to cold-resistant genes had high identity of 88~98% with low temperature-induced genes. The results indicate that the 6 genes were closely related to vernalization and cold-resistance during low temperature treatment.

• 한국생활과학회지
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• 제20권1호
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• pp.195-203
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• 2011

The purpose of this study was to define the effects of the finger temperature response according to the daily life of college student. For this study, 31 healthy female college students were taken as a subject group. To define the effects of the finger temperature response, housing style, subjective thermal sensations during daily life in the house and domestic working time were surveyed. The finger temperature response items were measured. The results were as follows. Strong, normal and weak group members were divided according to their cold resistance index(RI) 3, 8, 20 people, repectively. Subjective thermal sensations during daily life in the house affects the cold resistance index(p<.01). The cold resistance index(RI) got higher as domestic working time was increased(p<.05, F-value=3.927). The percentage wearing protective gloves during domestic work in the weak group was higher than the normal or strong groups. Subjective sensations during daily life and domestic working time effected the local cold tolerance, living in a comfortable environment continuously can weaken one's cold tolerance.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 가을 학술논문 발표대회
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• pp.165-166
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• 2020

The climate on the Korean Peninsula has been warmed recently, abnormal weather conditions such as heat waves, cold waves, and tropical nights have been detected frequently. Precisely, the number of days with cold waves in the winter has increased, and rapid changes of temperature in the morning and afternoon have occurred frequently in the 2000s. Due to the previous phenomenons, this research is focused on evaluating the concrete's Chloride Penetration Resistance and Durability, and the difference of the resistance according to the W/C.

• Elastomers and Composites
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• 제51권2호
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• pp.93-98
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• 2016

The composites of EVA/EPDM including aluminum trioxide (ATH) as a fire retardant were manufactured for the purpose of improving low temperature property and flame resistance in the rubbery materials. The ratio of EVA to EPDM didn't affect the flame resistance of the rubber composites. The addition of ATH resulted in increase of the flame resistance. In the evaluation of the cold resistance, the increasing EPDM content showed enhancement of cold resistance in the composites due to increasing low Tg EPDM. It was found out that tensile strengths of the composites showed a maximum value at 100 phr of ATH by reinforcing effect, but a minimum value at 200 phr of ATH owing to slippage between the flame retardant by the external stress. In the measurement of solvent resistance in tetrahydrofuran, the increasing ATH content yielded enhancement of solvent resistance by reducing swelling of the composite, and increasing EPDM content also resulted from increase of the solvent resistance by reduction of polarizability as well as increase of crosslink in the composites.

• 한국작물학회지
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• 제22권1호
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• pp.26-34
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• 1977

27 lines were selected for the cold resistant lines from the promising lines. The cold resistant lines were chiefly selected from Oro$\times$Norin 16, Oro$\times$Norin 20 and (Yudal$\times$Kongo)$\times$Yudal combination. The varieties of lately maturing showed cold resistantce. Transplanting treatment increased cold resistantce, and early sowing and drill planting also elevated cold resistance in the direct sowing culture. Plants to be cultured on soils with optimum moisture coutent showed higher cold resistance.

• 소성∙가공
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• 제8권3호
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• pp.227-227
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• 1999

The effects of intermediate annealing (IA) and the final cold rolling (CR) condition on the microstructure and sagging resistance during brazing were investigated using three layer clad sheets composed of the Al-7.5 wt.%Si alloy (filler, thickness: 10 ㎛)/Al-1.3 wt.%Mn based alloy (core, 80㎛)/Al-7.5 wt.%Si alloy (filler, 10㎛). Also, the effect of 1.2∼2 wt.% Zn addition into the core on the sagging resistance of the clad sheets was determined. It was revealed that all the clad sheets fabricated by the optimum condition (IA at 690 K and CR to 20∼45%) show excellent sagging resistance with a limited erosion due to the formation of a coarsely recrystallized grain structure in the core during brazing. It was also revealed that the recrystallization behavior of the Al-1.3 wt.%Mn based alloy is hardly affected by the addition of 1.2-2 wt.%Zn during the brazing cycle. Therefore, the sagging resistance of the clad sheets is found to be governed not by the Zn content added in the A1-1.3wt.%Mn based core, but by the intermediate annealing and final cold rolling condition.

• Plant Resources
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• 제7권2호
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• pp.147-154
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• 2004

Antifreeze proteins (AFPs) accumulate in the leaves of barley during cold acclimation, where they may inhibit ice recrystallization and produce freezing resistance of the plant. Four parental diallel crosses of the barley varieties were used to determine the heritability of AFPs and the relationship between the accumulation level of AFPs and freezing resistance. The concentration of apoplastic proteins in the cold-acclimated leaves was increased in the mean by four-fold over as compared with that of nonacclimated. The diallel cross analyses revealed that the gene of Sacheon 6 was dominant and those of Reno and Dongbori 1 were recessive. The AFPs had high narrow-sense heritabilities. The general combining ability effects of Reno and Dongbori 1 were much higher than the other parents. The bands of 32-kD for GLP, 35-& 28-kD for CLP and 25-, 22- & 16-kD for TLP were observed in the apoplastic extracts from cold-acclimated plants, but there were no clear differences between the parents and Fl hybrids. The concentrations of AFPs were significantly correlated with the degree of freezing resistance, indicating that the concentration of AFPs in the plant is the very important factor for freezing resistance.

• 한국도로학회논문집
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• 제20권3호
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• pp.1-9
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• 2018

PURPOSES : In order to evaluate a crack resistance at cold joint, sealing tape was adopted to apply at cold joint instead of typical tack coat material(RSC-4). The sealing tape was made by hot sealing material. The crack resistance as function of environmental and traffic loading was measured with visual observation. METHODS : In this study, the crack resistance was evaluated as function of environmental and traffic loading. The freeze-thaw method was adopted for environmental loading of asphalt pavement. condition. The damage of cold joint under freeze-thaw action is initiated by ice expansion load and accelerated by the interfacial damage between new and old asphalt pavement. The traffic loading was applied with wheel tracking machine on the cold joint area of the asphalt pavement for 3 hours at $25^{\circ}C$. The evaluation of crack resistance was measured with visual observation. The freeze-thaw results shows that the sealing tape was significantly increased the crack resistance based on. RESULTS : To estimate the crack resistance at cold joint area due to the environmental loading, the Freeze-thaw test was conducted by exposing the product to freezing temperature(approximately $-18^{\circ}C$) for 24 hours, and then allowing it to thaw at $60^{\circ}C$ for 24 hours. The tack coat material(RSC-4) was debonded after 21 cycles of the Freeze-thaw test. The first crack was observed after 14 freeze-thaw cycle with RSC-4 material. But, the sealing tape was not debonded after 24 cycle test. Also, the sealing tape shows the better performance of the crack resistance under the traffic loading with wheel track test. The crack was generated the under traffic loading with RSC-4(tack coating), however, the crack was not shown with sealing tape. It indicates that the sealing tape has a strong resistance of tensile stress due to traffic loading. CONCLUSIONS :Based on limited laboratory test result, a performance of crack resistance using the sealing tape is better than that of general tack coat material(RSC-4). It means that the sealing tape is possible to extend a pavement service life because the crack, one of the main pavement distresses, will be delayed.

• The Plant Pathology Journal
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• 제31권3호
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• pp.305-309
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• 2015

After four years of cold storage, dimethachlon resistance of two laboratory-induced resistant Sclerotinia sclerotiorum isolates SCG7 and LA50 declined by 99.5% and 98.9%, respectively, and cross resistance to iprodione and procymidone also declined dramatically. Along with the decline of fungicide resistance, osmotic sensitivity to sodium chloride and glucose decreased tremendously; mycelial growth rate, sclerotia number and weight per potato dextrose agar (PDA) plate increased on average by 118.6%, 85. 5% and 64.5%, respectively; and virulence to detached leaves of oilseed rape increased by 72.7% on average. Significant negative correlations were detected between dimethachlon resistance levels and mycelial growth rate on PDA (r = -0.980, P = 0.021), and between resistance levels and lesion diameters on detached leaves of oilseed rape plants (r = -0.997, P = 0.002). These results have profound implications for assessing the potential risk for resistance development to dicarboximide fungicides in S. sclerotiorum.