• Clean Technology
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• v.8 no.4
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• pp.199-203
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• 2002

To investigate the optimal conditions for biodegradation of toluene by Pseudomonas fluorescens KCTC 1767 in a batch soil-bioreactor, the effects of rpm change from 60 to 180, and temperature change from $15^{\circ}C$ to $30^{\circ}C$ in a batch culture and the flow rate change from 55 mL/min to 85 mL/Min in soil-bioreactor on the biodegradation of toluene were studied. In a batch culture the optimal operating conditons were 60 rpm, and $30^{\circ}C$ at initial pH 7, In a soil-bioreactor the optimal flow rate was 55 mL/min in the flow rate of circulation. The lower flow rate of circulation may help to biodegrade toluene adsorped in soil and dissolved in underground water.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.3
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• pp.521-527
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• 2002

In this paper, tensile behavior and low cycle fatigue behavior of 316L stainless steel which is currently favored structural material for several high temperature components such as the liquid metal cooled fast breeder reactor (LMFBR) were investigated. Research was performed at 55$0^{\circ}C$, $600^{\circ}C$ and $650^{\circ}C$ since working temperature of 316L stainless steel in a real field is from 40$0^{\circ}C$ to $650^{\circ}C$. From tensile tests performed by strain controls with $1{\times}10^{-3}/s,\; l{\times}10^{ -4}/s \;and\; 1{\times}10/^{ -5}/ s $ strain rates at each temperature, negative strain rate response (that is, strain hardening decreases as strain rate increases) and negative temperature response were observed. Strain rate effect was relatively small compared with temperature effect. LCF tests with a constant total strain amplitude were performed by strain control with a high temperature extensometer at R.T, 55$0^{\circ}C$, $600^{\circ}C$, $650^{\circ}C$ and total strain amplitudes of 0.3%~0.8% were used and test strain rates were $1{times}10^{-2} /s,\; 1{times}10^{-3} /s\; and\; 1{times}10^{-4} /s$. A new energy based LCF life prediction model which can explain the effects of temperature, strain amplitude and strain rate on fatigue life was proposed and its excellency was verified by comparing with currently used models.

• Journal of Sericultural and Entomological Science
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• v.33 no.1
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• pp.9-12
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• 1991

A study on dyeing-rate for single and mixture dyeing of silk with acid dyes was carried out. Single and mixture dyeings were performed with levelling and milling dyes at 7$0^{\circ}C$ and at pH 3, pH 4 and pH 5, respectively. The results of this study were summerized as follows : 1. C. I. Acid Orange 7. A) At pH 3, dyeing-rate was more fast in the single dyeing than in mixture dyeing at the beginning of dyeing process. B) At pH 4 and 5, dyeing-rates tend to get very similar in single and mixture dyeing. 2. C. I. Acid Blue 138 A) At all pH value, dyeing-rates were more fast in the mixture dyeing than single dyeing at the beginning of dyeing. B) As the time increased, the difference of dyeing-rate and adsorption amounts between single and mixture dyeing was not shown.

• Korean Journal of Veterinary Research
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• v.6 no.1
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• pp.24-30
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• 1966

In order to observe the effect of the injected radioactive iodine-$I^{131}$ on the uptake in thyroid of normal male guinea pigs and P.B.$I^{131}$ conversion ratio of $I^{131}$ in serum, 24 matured male guinea pigs were divided in 4 groups and $35{\mu}c$, $70{\mu}c$, $140{\mu}c$ and $280{\mu}c$ per kg of body weight respectively were injected subcutaneously. 1. The uptake rates of radioactveiodine-$I^{131}$ by external counts of thyroidal uptake reached the maximum level of uptake in 24 hours after injection. 2. As the injected amount increases, the uptake rates of maximum levels and release rate were increased. 3. Uptake rate in the removed thyroid have shown no statistical in the $35{\mu}c$ and $70{\mu}c$ groups of injected guinea pigs. 4. There was no statistical significance in $140{\mu}c$ and $280{\mu}c$ groups of injected guinea pigs. 5. P.B.$I^{131}$ conversion ratio of $I^{131}$ in serum was not in proportion to injected amounts: 61.0%(35), 70.2%(70), 75.3%(140) and 64.8%(280).

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.2
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• pp.191-198
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• 2011

According to the propagation of fuel cell system, the importance of that system efficiency is being magnified. Thus, the efficiency improvement of reformer which is the important factor of fuel cell system will be required. This study has been experimentally performed to evaluated the performance of plate type STR reactor. At first, we changed fuel flow rate (2, 3 and 4 l/min) in burner, and then we measured a proportion of hydrogen in produced gas through the STR reactor by G.C for evaluating the performance of plate type STR reactor in various fuel supply conditions. And we changed S/C ratio (2 and 4) and measured a proportion of hydrogen in produced gas through the STR reactor. As a results, condition at fuel flow rate 2 and 3 l/min could not be supplied amount of heat for STR sufficiently. Condition at fuel flow rate 4 l/min could supplied a heat excessively. And condition at S/C ratio 2, reaction occurred insufficiency. But condition at S/C ratio 4 was excess. From above, we found the optimum conditions that were fuel rate 3.5 l/min and S/C ratio 3.

• Korean Journal of Rural Living Science
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• v.5 no.1
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• pp.1-8
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• 1994

This study was conducted to examine whether there is any effect of the local body exposure to hot and cold alternate stress on the blood flow and heart rate. Environmental condition was $20^{\circ}C$ air temperature, 65% relative humidity and 0.2m/s air movement. 22~32 years old four healthy female subjects wore clothes which they felt comfort sitting on a chair. And then their left hand was immersed twice in ($42^{\circ}C$\;and\;15^{\circ}C$ water alternately. Two of the subjects (E-group) were continually exposed to above condition 12 times. While, the other two (C-group) were exposed twice only at the 1st and 12th time of E-group's exposure. The results obtained from this experiment were as follows. \circled1 The initial response of the finger blood flow in I-group to the thermal stress showed more sensitively at the post-training than pre-training. \circled2 Heart .ate was higher in hand immersion at hot water ($42^{\circ}C$) than at cold water ($15^{\circ}C$) \circled3 The pattern of the blood flow of the finger and heart rate was different between E-group and C-group.

• Journal of the Korean Society for Heat Treatment
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• v.21 no.6
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• pp.307-313
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• 2008

The tensile deformation and shape recovery behaviors were studied in Ni-Ti shape memory wires showing different transformation characteristics by annealing at $200{\sim}600^{\circ}C$. Both R phase ${\rightarrow}$ B19' martensitic transformation at lower temperature and B2 ${\rightarrow}$ R phase transformation at higher temperature occurred in the shape memory wires annealed at $200{\sim}500^{\circ}C$. Transformation temperature and heat flow of B19' martensite increase but those of R phase main almost constant even with increasing annealing temperature. In the case of wires annealed and then cooled to $20^{\circ}C$, plateau on stress-strain curves in tensile testing can be observed due to the collapse of R phase variants and the formation of deformation-induced B19' martensite. In the case of wires annealed and then cooled to $-196^{\circ}C$, however, plateau on stress-strain curves does not appear and stress increases steadily with increasing tensile deformation. Comparing shape recovery rate with cooling temperature after annealing, shape recovery rate of the wire cooled to $20^{\circ}C$ is higher than that of the wire cooled to $-196^{\circ}C$ after annealing, and maximum shape recovery rate of 95% appears in the wire annealed at $400^{\circ}C$ and then cooled to $20^{\circ}C$. $R_s$ and $R_f$ temperatures measured during shape recovery tests are higher than $A_s$ and $A_f$ temperatures measured by DSC tests even at the same annealing temperature.

• The Korean Journal of Physiology
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• v.7 no.1
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• pp.41-47
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• 1973

$Na^{+}$ balance was studied in Rana temporaria, which hibenates in fresh water in the winter time. $Na^{+}$ uptake rate, skin $Na^{+}$ loss rate, urinary $Na^{+}$ loss rate and $Na^{+}-K^{+}$ adenosine triphosphatase(ATPase) were measured at two different temperatures $1{\sim}2^{\circ}C\;and\;20{\sim}24^{\circ}C$ respectively. The results obtained were as follows: 1. $Na^{+}$ uptake rates in the frog in an artificial Pond water (APW) were found to be $8.28{\pm}0.73\;and\;2.19{\pm}0.37\;{\mu}Eq/g/day\;at\;20{\sim}24^{\circ}C\;and\;1.0{\sim}2.5^{\circ}$ respectively. 2. $Na^{+}$ loss rate through the frog skin to APW were found to be $4.26{\pm}0.72\;and\;0.93{\pm}0.21\;{\mu}Eq/g/day$ at the same temperatures. 3. Mean rates of urinary $Na^{+}$ loss at $20{\sim}24^{\circ}C\;and\;3{\sim}4^{\circ}C$ were found to be $3.02{\pm}0.73\;and\;0.78{\pm}0.13\;{\mu}Eq/g/day$ respectively. 4. The activities of $Na^{+}-K^{+}$ activated ATPase of frog skin fragments were found to be $258{\pm}39.4\;and\;49.6{\pm}7.1\;{\mu}M\;Pi/g$ protein/hr at $24^{\circ}C\;and\;2^{\circ}C$ respectively. From the above results, it may be concluded that frogs can take up enough $Na^{+}$ through the skin from APW exceeding skin loss Plus urinary loss at $1{\sim}2^{\circ}C$. It is suggested that $Na^{+}$ transport across frog skin is closely related with $Na^+-K^+$ ATPase since $Q_{10}\;of\;Na^{+}$ uptake is much similar to that of the activities of $Na^{+}-K^{+}$ ATPase.

• Food Science and Preservation
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• v.11 no.1
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• pp.7-11
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• 2004

To examine the effect of storage condition on the quality and microbiological change of strawberry “Minyubong”, the rate of weight loss, decay rate, pH and titratable acidity, and microbial (total bacterial count, mold and yeast) changes were determined during storage. Strawberry fruits were packaged with low-density polyethylene (LDPE). Strawberries were then stored at 4$^{\circ}C$ and 20$^{\circ}C$, respectively. LDPE package was effective on the decrease of decay rate of strawberry as well as the rate of weight loss, compared with the non-packaged. Microbial changes of strawberry stored at 4$^{\circ}C$ and 20$^{\circ}C$ were monitored during storage. Packaging affected the microbial change, resulting in retarding the growth of total bacteria as well as mold and yeast, compared with the non-packaged, regardless of storage temperature. These results indicate that storage of strawberry fruits wrapped with LDPE at 4'C should be recommended in terms of quality as well as its shelf-life.

• Agribusiness and Information Management
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• v.6 no.2
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• pp.1-12
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• 2014

HMR is a home-style food product designed for convenience and cooked outside the home leaving out cumbersome cooking process and consumed at home. The present paper aims to find out factors that influence the consumption of HMR by analyzing data on food consumption during the 3 years between December 2010 and November 2013. Following the classification of Costa et al. (2001), this study categorized HMR products as 3 types as follows: C1 (ready to eat), C2 (ready to heat) and C3 (ready to cook), and examined factors affecting purchase rate and per capita purchase price for each type of HMR product. The results of our analysis show that only the purchase rate of C3 products was influenced by whether the purchaser was housewife with job or not. For those who do not live together with parents, per capita purchase price for HMR was high; and the more they ate out, the higher the purchase rate of HMR was.