• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.317-325
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• 1988

The effects of various heat treatments of soy milk prepared from soy protein concentrate on growth and acid production by five species of lactic acid bacteria were investigated. Sensory property and sedimentation characteristics of soy yogurt prepared from heat-treated soy milk were also evaluated. Heat treatment of soy milk stimulated acid production by all cultures. Acid production was generally proportional to degree of heat treatment and acid production by all cultures except Streptococcus lactis was maximum in soy milk heated at $121^{\circ}C-1min$. However, viable cell count was not changed markedly by heat treatment of soy milk. Sensory property of soy yogurt beverage (SYB) prepared from soy milk heated at $95^{\circ}C-30min$ was better than that of unheated sample while sensory property of SYB prepared from soy milk heated at $121^{\circ}C-15min$ was inferior to that of unheated sample. Heat treatment of soy milk generally retarded sedimentation of curd in SYB.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.4
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• pp.669-676
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• 1997

The purpose of this study is to examine the effect of the improved cold tolerance resulting from cool clothing in winter on heat tolerance in summer. Ten healthy women were divided into two groups, cold group(C group) (n=5) and warm group(W group) (n=5) . In the previous study, C group was proved that their cold acclimatization was achieved through wearing cool clothing from September to February of the following year, while Wgroup was not proved because of wearing warm clothing during same period. After February, no more clothing training was continued in two groups. To determine the heat tolerance, both groups were exposed from a thermoneutral environment(25$\pm$1$^{\circ}C$, 50$\pm$5% R.H.) to a hot environment (35$\pm$1$^{\circ}C$, 50$\pm$5% R.H.) before and after clothing training, respectively September in 1994 and truly in 1995. Rectal temperature, skin temperatures, thermal sensation and comfort were measured every 10 min., and Os uptake was measured at 10, 45, 85 min. after entering the chamber for 5 min. Body weight was measured before and after the experiment and amount of local sweat was measured during the 90 min long experiment. The results are as follows: Rectal temperatures in 35'c environment of C group were increased after training when compared with before clothing, while those of W group were not changed. But the changes of rectal temperature and heat production during 90 min in hot environment were almost the same in two groups after training. And mean skin temperatures, the changes of mean skin temperatures during 90 min in hot environment, total sweat amount and local sweat amount after training were also the same in two groups. From these results, it might be supposed that the heat loss of two groups were the same but the heat production, especially heat production during rest in C group was higher than in Wgroup. This fact suggests that the increase of rest heat production from cold acclimatization in winter is maintained to summer of the following year. And mild cold acclimatization coming from westing cool clothing does not have a negative effect on heat tolerance.

• Journal of Institute of Convergence Technology
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• v.5 no.1
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• pp.1-5
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• 2015

SI thermochemical hydrogen production process achieves water splitting into hydrogen and oxygen through three chemical reactions. The process is comprised of three sections and one of them is HI decomposition into $H_2$ and $I_2$ called as Section III. The production of $H_2$ included processes involving EED for concentrating a product stream from Section I. Additionally an $I_2$ crystallization would be considered to reduce burden on EED by removing certain amount of $I_2$ out of a process stream prior to EED. In this study, the current thermodynamic model of SI process was briefly described and the calculation results of the applied Electrolytes NRTL model for phase equilibrium calculations was illustrated for ternary systems of Section III. We calculated temperature and heat duty of an $I_2$ crystallizer and heat duty of heaters using UVa model and heat balance equation of simulation tool. The results were expected to be used as operation information in optimizing HI decomposition process and setting up material balance throughout SI process.

• Journal of the Korean Solar Energy Society
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• v.37 no.2
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• pp.13-22
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• 2017

Two-step water splitting thermochemical cycle with $CeO_2/ZrO_2$ foam device was investigated by using a solar simulator composed of 2.5 kW Xe-Arc lamp and mirror reflector. The hydrogen production of $CeO_2/ZrO_2$ foam device depending on heat recovery of Thermal-Reduction step and Water-Decomposition step was analyzed, and the hydrogen production of $CeO_2/ZrO_2$ and $NiFe_2O_4/ZrO_2$ foam devices was compared. Resultantly, the quantity of hydrogen generation increased by 52.02% when the carrier gas of Thermal-Reduction step is preheated to $200^{\circ}C$ and, when the $N_2/steam$ is preheated to $200^{\circ}C$ in the Water-Decomposition step, the quantity of hydrogen generation increased by 35.85%. Therefore, it is important to retrieve the heat from the highly heated gases discharged from each of the reaction spaces in order to increase the reaction temperature of each of the stages and thereby increasing the quantity of hydrogen generated through this.

• Journal of the Korean Society for Heat Treatment
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• v.18 no.2
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• pp.119-125
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• 2005

• Korean Chemical Engineering Research
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• v.52 no.4
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• pp.459-466
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• 2014

SI Cyclic process is one of the thermochemical hydrogen production processes using iodine and sulfur for producing hydrogen molecules from water. VHTR (Very High Temperature Reactor) can be used to supply heat to hydrogen production process, which is a high temperature nuclear reactor. IHX (Intermediate Heat Exchanger) is necessary to transfer heat to hydrogen production process safely without radioactivity. In this study, the strategy for the optimum design of IHX between SI hydrogen process and VHTR is proposed for various operating pressures of the reactor, and the different cooling fluids. Most economical efficiency of IHX is also proposed along with process conditions.

• Nuclear Engineering and Technology
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• v.53 no.6
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• pp.2066-2073
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• 2021

The use of nuclear reactors is a large studied possible solution for thermochemical water splitting cycles. Nevertheless, there are several problems that have to be solved. One of them is to increase the efficiency of the cycles. Hence, in this paper, a thermal energy optimization of a Sulfur-Iodine nuclear hydrogen production cycle was performed by means a heuristic method with the aim of minimizing the energy targets of the heat exchanger network at different minimum temperature differences. With this method, four different heat exchanger networks are proposed. A reduction of the energy requirements for cooling ranges between 58.9-59.8% and 52.6-53.3% heating, compared to the reference design with no heat exchanger network. With this reduction, the thermal efficiency of the cycle increased in about 10% in average compared to the reference efficiency. This improves the use of thermal energy of the cycle.

• Journal of Microbiology and Biotechnology
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• v.31 no.4
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• pp.570-583
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• 2021

Pyrococcus furiosus α-amylase can hydrolyze α-1,4 linkages in starch and related carbohydrates under hyperthermophilic condition (~ 100℃), showing great potential in a wide range of industrial applications, while its relatively low productivity from heterologous hosts has limited the industrial applications. Bacillus subtilis, a gram-positive bacterium, has been widely used in industrial production for its non-pathogenic and powerful secretory characteristics. This study was conducted to increase production of P. furiosus α-amylase in B. subtilis through three strategies. Initial experiments showed that co-expression of P. furiosus molecular chaperone peptidyl-prolyl cis-trans isomerase through genomic integration mode, using a CRISPR/Cas9 system, increased soluble amylase production. Therefore, considering that native P. furiosus α-amylase is produced within a hyperthermophilic environment and is highly thermostable, heat treatment of intact culture at 90℃ for 15 min was performed, thereby greatly increasing soluble amylase production. After optimization of the culture conditions (nitrogen source, carbon source, metal ion, temperature and pH), experiments in a 3-L fermenter yielded a soluble activity of 3,806.7 U/ml, which was 3.3- and 28.2-fold those of a control without heat treatment (1,155.1 U/ml) and an empty expression vector control (135.1 U/ml), respectively. This represents the highest P. furiosus α-amylase production reported to date and should promote innovation in the starch liquefaction process and related industrial productions. Meanwhile, heat treatment, which may promote folding of aggregated P. furiosus α-amylase into a soluble, active form through the transfer of kinetic energy, may be of general benefit when producing proteins from thermophilic archaea.

• YAKHAK HOEJI
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• v.49 no.1
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• pp.80-85
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• 2005

Ginseng root is an important remedy in oriental countries, which has been used for thousands of years. Saponins of ginseng root has been known to be the major component which mediate diverse pharmacological actions of the ginseng. Heat processing of ginseng root potentiates its biological activity such as anti-tumor and anti-oxidative activities. The butanol fraction of heat-processed ginseng (HGB) induced the production of nitric oxide in macrophages in a dose-dependent manner with IFN-${\gamma}$(30 U/ml) priming. The active component was identified as ginsenoside-$Rg_5$ from the activity-guided purification. Ginsenoside $Rg_5$ is one of major components of heat-processed ginseng and red ginseng that is responsible for the potentiated biological activities of processed ginseng. The induction of NO production by heat-processed ginseng might contribute to the potentiated biological activity of heat-processed ginseng.

• Animal Bioscience
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• v.36 no.4
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• pp.540-554
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• 2023

Heat stress is a major challenge to animal production in tropical and subtropical climates. Rabbits suffer from heat stress more than farm animals because they have few sweat glands, and their bodies are covered with thick fur. Intensive farming relies on antibiotics as antimicrobials or growth promoters to increase animals' productivity and health. However, the European Union and many countries have banned or restricted the use of antibiotics in animal feed for human health concerns. Several studies have found that replacing antibiotics in rabbit feed with natural plants or feed additives increases productivity and improves immune capacity, especially under heat stress conditions. Growth performance, immune response, gut microflora, and carcass yield may be increased in rabbits fed a diet supplemented with some natural plants and/or propolis. In this review article, we discuss and summarize the effects of some herbs and plant extracts as alternative feed additives on rabbit productivity, especially for those raised under hot ambient temperatures.