• Journal of the East Asian Society of Dietary Life
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• v.18 no.3
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• pp.368-375
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• 2008

This study examined the physico-chemical properties of omija extracts that were manufactured using various water temperatures($0^{\circ}C$, $23^{\circ}C$, $70^{\circ}C$) and immersion times(12 hrs, 18 hrs, 24 hrs). The results were as follows: The pH levels of the extracts ranged from 2.86 to 2.95: however, there were no significant differences between the samples according to the various water temperatures and immersion times. The total organic acid contents of the samples ranged from 1.87 to 2.57%, and included citric acid, malic acid, and succinic acid at levels of $1.11{\sim}1.54%$, 0.49{\sim}0.66%$, and $0.25{\sim}0.38%$, respectively. As the immersion time and water temp. is erature increased the level of total organic acid significantly increased(p<0.01). The sugar contents of samples ranged from 3.01 to 3.90% brix, and did not show significant differences according to the immersion times at the different water temperatures(0, 23, $70^{\circ}C$). The Omija extract that was immersed in water for 24 hrs. at $70^{\circ}C$ had a significantly higher(p<0.05) sugar content than the other samples. The total free sugar contents of samples ranged from 0.714 to 0.833%, and included glucose, fructose, and sucrose at levels of $0.37{\sim}0.42%$, 0.34{\sim}0.41%$, and $0.003{\sim}0.004%$, respectively. The Omija extract that was immersed in water for 18 hrs. at $70^{\circ}C$ water had a significantly higher(p<0.05) total free sugar content than the other samples. The lightness, redness, and yellowness values of the samples were in ranges of $49.09{\sim}58.25$, 62.37{\sim}67.34$, and $19.76{\sim}24.57$, respectively; therefore, red was the predominant color of the extracts. Overall, as the immersion time and water temperatures increased is, lightness significantly decreased and redness significantly increased(p<0.001).

• Development and Reproduction
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• v.15 no.4
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• pp.301-308
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• 2011

The tolerance evaluation for abalone Haliotis discus hannai embryos was performed using different concentrations of cryoprotective agents (CPAs): dimethyl sulfoxide, ethylene glycol and propylene glycol added to 0.2 M sucrose, respectively. 4-cell, trochophore and veliger were exposed in each CPA with different concentration for 10, 20 and 30 minutes of immersion time. Developmental rates were increased with decreased concentration of every CPA and decreased immersion time, and differed from types of CPA. Developmental rates of veliger in all the CPAs were higher than those of 4-cell and trochophore. The developmental rates and larval activity indices in ethylene glycol were comparatively higher than those in other CPAs and the effective CPA and its concentration for the cryopreservation of the abalone embryos was suggested as 2.0 M ethylene glycol with equilibration time of 30 minutes.

• The Journal of the Korea Contents Association
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• v.18 no.2
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• pp.652-660
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• 2018

The common point between and is that the immersion was high at the point where all the place movements occurred in the narrative before the full-blown incident occurred. The immersion level showed the maximum at the turning point that passed to the place. Seven key events occur, and the audience's immersion is peaking at the time of each incident. The core event and the immersion are highly correlated. It is at a point where the background, such as movement from the third act, where the most central event is solved, or return to the original place, is changing. The immersion degree of the audience is closely related to the narrative from the first film to the third film of the narrative.

• The Korean Journal of Physiology
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• v.3 no.1
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• pp.59-66
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• 1969

Experiments on thermoregulatory responses to cold immersion stimulus were carried out in September, 1968 (summer studies) and February, 1969 (winter studies). Eight each of ama and control subject were selected at random from a same community in Yong-Do Island, Pusan. The results obtained are summarized as follows: 1) The rate of fall in muscle temperature of forearm during a 30 min-immersion in $6^{\circ}C$ water bath was significantly slower in the ama in winter and was about the same in the two groups in summer. However, the magnitude of change in the skin temperature and the heat fluxes observed during immersion period was not significantly different either between groups or between seasons. 2) Both finger blood flow and skin temperature during one hr-immersion in $6^{\circ}C$ water bath decreased significantly in the ama as compared to the control. The magnitude of cold-induced vasodilatation during immersion period was significantly greater in the control in winter. However, the time of onset and blood flow at onset showed no significant relation between groups. 3) The magnitude of reactive hyperemia after a 5 min-arterial occlusion in both air and $15^{\circ}C$ water bath was significantly lower in the ana than in the control. In control subjects, post-occluded blood flow in water was significantly greater than in air, while in the ama it decreased to 1/2 of control values. The time required for the return of blood flow to resting values in the air was faster in the ama than in the control but was the same in water in the two groups. 4) The results suggest that vasoconstrictor tone increased in the ama in winter, indicating the development of vascular adaptation as a part of cold acclimatization.

• Journal of Ocean Engineering and Technology
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• v.14 no.3
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• pp.90-99
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• 2000

This study has been investigated about the influence of moisture environment properties in the unidirectional and cross laminated carbon fiber/epoxy and glass fiber/epoxy composites. As a results, it was found that the weight gain of water increased with the immersion time and the mechanical properties were decreased with the weight gain of water. And it was also shown that the mechanical properties of carbon fiber/epoxy laminates were better than those of glass fiber/epoxy laminates. And a gap of the mechanical properties between the two kinds of laminates was increasing with the immersion time in distilled water of 80$^{\circ}C $. Mechanical properties which decreased by moisture absorption in the CF and GF reinforced laminates were recovered up to some extent by drying in oven at 80$^{\circ}C $ for 10 days.

• Korean Journal of Materials Research
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• v.17 no.4
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• pp.192-197
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• 2007

The effects of immersion time in the liquid nitrogen on the behavior of aluminum alloys used for the hydrogen storage tank of auto-mobile at cryogenic temperature were investigated. With increasing immersion time in the liquid nitrogen, the elongation of AI 5083 alloy at cryogenic temperature decreased because of non-uniform fracture of precipitates on the grain boundary, and the serration also occurred because of discontinuous slip due to rapid decreasing of the specific heat. The mechanical properties of AI 6061 alloy at cryogenic temperature were characterized by uniformed yield strength, tensile strength and elongation regardless of the immersion time in the liquid nitrogen. These mechanical properties of aluminum alloys at cryogenic temperature were interpreted by the strength of grain boundary and the slip deformation behavior.

• Corrosion Science and Technology
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• v.21 no.6
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• pp.423-433
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• 2022

The objective of this study was to determine whether Cymbopogon citratus extract as a corrosion inhibitor from natural tropical resources could prevent corrosion of carbon steel in sulfuric acid solution. Inhibitory action of this extract was investigated using electrochemical methods such as potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Those methods revealed corrosion rate, efficiency of inhibition, and adsorptions isotherm values when the extract was added to the sulfuric acid solution at concentration up to 500 ppm with various immersion time at ambient temperature. Results revealed that higher concentration of the extract and longer immersion time decreased the corrosion rate of carbon steel whereas the inhibition efficiency of the extract was increased up to 97.25%. The value of charge transfer resistance was increased significantly by adding the extract at concentration up to 500 ppm with an immersion time of 60 minutes. The type of the extract was a mixed inhibitor. It could inhibit the corrosion process in both anodic and cathodic sides electrochemically. Results of this study suggest that the mechanism of adsorption on the surface of carbon steel is related to Langmuir adsorption isotherm.

• Corrosion Science and Technology
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• v.23 no.1
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• pp.20-32
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• 2024

Metal corrosion in acidic environments is a major issue in various industrial applications. This study evaluates the 4-piperonylideneaminoantipyrine (PPDAA) corrosion inhibition efficiency for mild steel in a hydrochloric acid (HCl) solution. The weight loss method was used to determine the corrosion inhibition efficiency at different concentrations and immersion time periods. Results revealed that the highest inhibition efficiency (94.3%) was achieved at 5 mM concentration after 5 hours of immersion time. To inspect the surface morphology of the inhibitor film on the mild steel surface, scanning electron microscopy (SEM) was used before and after immersion in 1.0 M HCl. Density functional theory (DFT) calculations were performed to investigate the molecular structure and electronic properties of the inhibitor molecule to understand the corrosion inhibition mechanism. Theoretical results showed that the inhibitor molecule can adsorb onto the mild steel surface through its nitrogen and oxygen atoms, forming a protective layer that prevents HCl corrosive attack. These findings highlight the potential of PPDAA as an effective corrosion inhibitor for mild steel in HCl solution. Moreover, combining experimental and theoretical approaches provides insights into the mechanism of corrosion inhibition, which is essential for developing effective strategies to prevent metal corrosion in acidic environments.

• Food Science of Animal Resources
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• v.23 no.1
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• pp.21-27
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• 2003

This study was carried out to investigate the effect of curing method(tumbling and immersion) and curing time (10 min to 48 hrs) on pH, color, product yield, cooking yield, water holding capacity, shear force, and sensory evaluation of cured pork meat with soy sauce. Curing method had an effective on color of cured meat(before cooking), Meats were tumbled for 30 min, followed by 24 hr and 48 hr delay period showed higher lightness than meat immersed for 24 and 48 hrs, respectively. Tumbling processing improved product yield and cooking yield as compared to immersion counterpart. Therefore, tumbled meat had significantly greater product yield(p <0.05) during working time for 30 min. Increasing curing time improved water holding capacity and tenderness. Although curing time had no influence on sensory evaluation, tumbling processing improved sensory evaluation of texture, juiciness, and overall acceptability fer cured pork meat with soy sauce, as compared to immersion counterpart.

• the MEAT Journal
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• s.34 winter
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• pp.48-59
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• 2007

The purpose of this study was to investigate the effect of marination condition(immersion and tumbling) on quality characteristics of cured pork meat and sensory properties of pork jerky. Pork meat was immersed for 1, 6, 12, 24, and 48 hours or tumbled for 10, 20, 30, and 60 minutes with curing solution. The jerky was made from cured pork meat, immersed for 6, 12, 24, and 48 hours or tumbled for 10, 20, 30, and 60 minutes. The curing yields and water holding capacity in immersion and tumbling treatments were increased as marination time increased, and the curing yields of tumbling treatments were higher than those of immersion treatments, but water holding capacity was not. The pH value of all treatments were not significantly different. CIE L*- and b*-value of immersion treatments were significantly decreased as marination time increased, but CIE a*-value were increased. Objective color of tumbling treatments showed a similar tendency with those of immersion treatment. The sensory properties of pork jerky were not significantly different between immersion and tumbling treatments.