• The Journal of Natural Sciences
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• v.11 no.1
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• pp.23-26
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• 1999

Phase separation temperature of lysozyme-water mixture increased with X-ray exposure on lysozyme and decreased with impurity of saponin. The intensity of light scattering in lysozyme-water mixture with X-ray exposure on lysozyme decreased as a function as a function of temperature, and decreased with impurity of saponin.

• Membrane and Water Treatment
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• v.13 no.1
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• pp.21-28
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• 2022

The use of plastics in our everyday lives have been drastically increased during the last few decades. However with the usage of commercial plastic products there is a possibility of microplastic consumption, due to the fragmentation of the products. Additionally, the potential for microplastic ingestion may also be increased by using damaged products. Hence, the current study was conducted to understand the potential release of micro/nano plastics and organic matter from damaged teabags. To check the leakage tendency, the amount of damage to the tea bags from 1-10 cm were tested along with temperatures of 25-70℃, and exposure times from 5 min to 1 hr was tested. Release of fibrous micro/nanoplastics, and organic leachate from the damaged teabags were observed to understand the outflow conditions. Results showed that with the increased degree of damage, temperature, and exposure time increased the release of fiberous matter, where the increase of temperature, and exposure time increased organic leachate. Additional analysis confirmed the leachate of nylon polymers into the heated water.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.36T no.2
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• pp.70-76
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• 1999

With the recent increase in the use among young children of portable telephone public concern regarding potential health hazards due to a hot spot appearing inside the infant head, has been growing. Since the biological hazards due to RF exposure are caused mainly by a temperature-rise in tissue, the effect of localized SAR for portable telephones should also be related to the temperature-rise in the human head. In this paper, it was measured that in the actual use of portable telephone the temperature of the local tissue in the human-head change. As a result, it should be noted that the mean temperature of human-body and localized tissue is rising from beginning call. However the temperature variation of localized tissue is recovered rapidly as normal temperature, although the mean temperature of human-body rising continuously at ending call of portable telephone.

• The Korean Journal of Malacology
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• v.26 no.2
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• pp.151-156
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• 2010

For industrialization of the hard clams, Meretrix petechiails (Lamarck), spawning was induced per spawning induction technique in the artificial maturation group administered of parent maturation control and the natural maturation group of which parents were transported for artificial spawning per time period. Then, fertilization rates, hatching rates and D-shaped larva development rates were investigated. In addition, growth and survival rates of larvae were investigated per larva breeding technique. The results of spawning induction by exposure in the artificial maturation group indicated that response rates were relatively higher at 23% and 32% respectively at the 4th hour and the 8th hour of exposure. In terms of water temperature increase, responses began only when the temperature reached $28^{\circ}C$ or higher. In the experiment group administered with both exposure and water temperature increase techniques, response rate was found to be 45% or higher at the 4th hour of exposure and the temperature of $28^{\circ}C$. At the temperatures of 29, 30 and $31^{\circ}C$, significant differences were not observed. Therefore, it was indicated that the response rates of parent hard clams were higher toward water temperature increase than exposure time. As for spawning induction per time period of the transported parent group, response rate and D-shaped larva development rate were the highest at 67.6% and 96% respectively on August 6, 2009. In terms of water temperatures during larva breeding experiment, growth was faster as water temperature was higher. In addition, growth and survival rates were relatively higher at the salinity of 25. In terms of stocking density, growth and survival rates were relatively higher at 5 inds./mL.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.7
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• pp.988-995
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• 2019

Objective: This study was conducted to estimate the temperature and microbial changes of corn silages during aerobic exposure. Methods: Kwangpyeongok (KW) and Pioneer 1543 (PI) corn hybrids were harvested at 29.7% of dry matter and chopped to 3 to 5 cm lengths. Homo (Lactobacillus plantarum; LP) or hetero (Lactobacillus buchneri; LB) fermentative inoculants at $1.2{\times}10^5$ colony forming unit/g of fresh forage was applied to the chopped corn forage which was then ensiled in quadruplicate with a $2{\times}2$ (hybrid${\times}$inoculant) treatment arrangement for 100 days. After the silo was opened, silage was sub-sampled for analysis of chemical compositions, in vitro digestibility, and fermentation indices. The fresh silage was continued to determine aerobic exposure qualities by recorded temperature and microbial changes. Results: The KW silages had higher (p<0.01) in vitro digestibilities of dry matter and neutral detergent fiber than those of PI silages. Silages applied with LB had higher (p<0.001) acetate concentration, but lower (p<0.01) lactate concentration and lactate to acetate ratio than those of LP silages. The interaction effect among hybrid and inoculant was detected in acetate production (p = 0.008), aerobic stability (p = 0.006), and lactic acid bacteria count (p = 0.048). The yeast was lower (p = 0.018) in LB silages than that in LP silages. During the aerobic exposure, PI silages showed higher (p<0.05) temperature and mold than KW silages, while LP silages had higher (p<0.05) lactic acid bacteria and yeast than LB silages. Conclusion: The results indicated that the changes of silage temperature during aerobic exposure seems mainly affected by mold growth, while applied LB only enhanced aerobic stability of PI silages.

• Advances in materials Research
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• v.5 no.1
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• pp.21-34
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• 2016

Fire is one of the most destructive powers to which a building structure can be subjected, often exposing concrete elements to elevated temperatures. The relative properties of concrete after such an exposure are of significant importance in terms of the serviceability of buildings. Unraveling the heating history of concrete and different cooling regimes is important for forensic research or to determine whether a fire-exposed concrete structure and its components are still structurally sound or not. Assessment of fire-damaged concrete structures usually starts with visual observation of colour change, cracking and spalling. Thus, it is important to know the effect of elevated temperatures on strength retention properties of concrete. This study reports the effect of elevated temperature on the mechanical properties of the concrete specimen with polypropylene fibres and cooled differently under various regimes. In the heating cycle, the specimen were subjected to elevated temperatures ranging from $200^{\circ}C$ to $800^{\circ}C$, in steps of $200^{\circ}C$ with a retention period of 1 hour. Then they were cooled to room temperature differently. The cooling regimes studied include, furnace cooling, air cooling and sudden cooling. After exposure to elevated temperatures and cooled differently, the weight loss, residual compressive and split tensile strengths retention characteristics were studied. Test results indicated that weight and both compressive and tensile strengths significantly reduce, with an increase in temperature and are strongly dependent on cooling regimes adopted.

• Restorative Dentistry and Endodontics
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• v.8 no.1
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• pp.115-121
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• 1982

Sodium hypochlorite solution has been widely used as endodontic irrigant due to its ability to dissolve pulp tissue debris and its antimicrobial action. This in vitro study was conducted to evaluate the solvent action of sodium hypochlorite solution on vital pulp tissue under various conditions include concentration, exposure time, and temperature. The percentage of weight loss due to pulp tissue dissolution was calculated with weight difference of lyophilized specimens before and after the exposure to test solutions. The results were as follows; Statistical analysis indicated that the ability of both 5.0% and 2.5% sodium hypochlorite solutions to dissolve pulp tissue was significantly greater than that of distilled water, but no significant difference was found between 5.0% and 2.5% sodium hypochlorite solutions. There was no significant increase in the pulp tissue dissolving ability of sodium hypochlorite solutions; as exposure time increased 2 minutes, 5 minutes, and 10 minutes. Of the given temperatures, no significant difference was found in the solvent aciton of sodium hypochlorite solution on pulp tissue between $20^{\circ}C$ (room temperature) and $37^{\circ}C$(body temperature).

• International Journal of Railway
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• v.1 no.3
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• pp.113-116
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• 2008

The long-tenn exposure of polymeric composite materials to extreme-use environments, such as pressure, temperature, moisture, and load cycles, results in changes in the original properties of the material. In this study, the effect of combined environmental factors such as ultraviolet ray, high temperature and high moisture on mechanical and thermal analysis properties of glass fabric and phenolic composites are evaluated through a 2.5 KW accelerated environmental aging tester. The environmental factors such as temperature, moisture and ultraviolet ray applied of specimens. A xenon-arc lamp is utilized for ultraviolet light and exposure time of up to 3000 hours are applied. Several types of specimens - tensile, bending, and shear specimens that are warp direction and fill direction are used to investigate the effects of environmental factors on mechanical properties of the composites. Mechanical degradations for tensile, bending and shear properties are evaluated through a Universal Testing Machine (UTM). Also, storage shear modulus, loss shear modulus and tan a are measured as a function of exposure time through a Dynamic Mechanical Analyzer (DMA). From the experimental results, changes in material properties of glass fabric and phenolic composites are shown to be slightly degraded due to combined environmental effects.

• Fisheries and Aquatic Sciences
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• v.22 no.1
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• pp.3.1-3.8
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• 2019

The purpose of this study is to investigate the changes in growth, hematological parameters, and plasma components of juvenile starry flounder, Platichthys stellatus, following exposure to varying arsenic concentrations present at different water temperatures. P. stellatus (total length, $15.9{\pm}0.4cm$; body weight, $62.2{\pm}4.2g$) were exposed for 4 weeks to waterborne arsenic (sodium arsenite, As) at 0, 150, 300, and $600{\mu}g/L$ at temperatures of $12^{\circ}C$ and $18^{\circ}C$. Toxic effects of As exposure on P. stellatus were higher at the higher temperature and the growth and hematological parameters measured decreased with increasing arsenic concentration, while the concentration of plasma components measured increased. This indicates that waterborne As exposure and water temperature can cause toxic effects on growth, hematological parameters, and plasma components in Platichthys stellatus.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.536-538
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• 2011

In this study, the moisture absorption behaviors of the CNT reinforced unsaturated polyester composites were investigated along with exposure temperature and time. The tensile properties of the specimens were evaluated to identify the effect of absorbed moisture on the mechanical properties. The exposure temperatures of $25^{\circ}C$ and $75^{\circ}C$ were considered and the exposure time up to 600 hours was applied. According to the results, moisture absorption rate was increased as CNT content and exposure temperature were increased. The rate of decrease in tensile strength of the CNT reinforced unsaturated polyester composites was reduced due to the reinforcing effect of CNT compared to the unsaturated polyester resin.