• Journal of Energy Engineering
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• v.17 no.1
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• pp.23-30
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• 2008

The neutron kinetic analysis methods for the molten-salt reactors are quite different from those for conventional solid-fuel reactors, which do not take into account the flowing-fuel-induced neutronics effects. Therefore, for dynamics and safety analyses of the molten-salt reactor systems, the conventional kinetics codes would not be appropriate to accurately predict its transient behaviors. A point-kinetics with flowing- fuel model has been used to assess the fluid-fuel reactor system safety, but recognized as not to be sufficient to simulate spatial distributions of delayed-neutron precursors and neutron populations during transients for given detail reactor models. In order to meet this requirement, AMBIKIND, a 2-group, 2-dimensional neutron kinetics code suitable for the molten-salt reactor systems was developed. This paper explains the code's theoretical and numerical descriptions and, as a part of its verification, includes some simulation results of MSRE stability experiments. Even though the present reactor model does not include the recirculation effect of the fuel-salt through the reactor system, the AMBIKIN2D code should be able to predict the power and phase shift at various power levels and reactivity insertions with better accuracy.

• Nutrition Research and Practice
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• v.3 no.4
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• pp.328-333
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• 2009

The average sodium intake of Koreans was reported to be 5,279.9 mg/day, which is one of the highest intake levels worldwide. The average Koreans intake 19.6% of sodium from kimchi, showing kimchi as the main contributor of sodium in this country (Ministry of Health and Welfare, 2005). The sodium content of dishes that are frequently chosen by workers, and which were served by foodservice cafeterias were chemically analyzed. The average sodium content of one meal provided by 10 foodservice cafeterias was 2,777.7 mg. Twenty-one, one-dish-meals, frequently chosen by workers for a lunch menu, were collected at 4 different restaurants for each menu by one male, aged in the twenties and analyzed chemically also. Workers who eat lunch at a workplace cafeteria everyday could intake about 8 g of salt at a one-time meal and those who eat out for a one-dish-meal would intake 3-8 g of salt without counting sodium content from the side dishes. From these study results, one could estimate that over 10 g of salt could be possible for a single meal for workers who eat out everyday. A nationwide nutrition campaign and education for low salt diets for restaurant owners and foodservice providers should be seriously considered.

• Journal of the Korean Society of Food Culture
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• v.32 no.3
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• pp.258-265
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• 2017

Although excessive intake of sodium is known to cause various diseases and threaten public health and policies for reducing overconsumption of sodium are being implemented, the theoretical research on sodium intake is incomplete. This study attempted to provide a policy basis by examining whether or not planned behavior theory, which is a typical health communication theory used to describe health-related behaviors, can be applied to explain sodium intake behavior. Especially, sodium ingestion behaviors were compared using the theory of actions planned for men and women as well as young people, middle-aged, and elderly persons, who are predicted to show differences in eating habits. In this study, questionnaires were prepared to measure the daily eating habits of subjects and subordinate factors of planned behavior theory: behavioral beliefs, outcome expectations, normative beliefs, compliance motivation, and control beliefs. Questionnaires were given to 93 college students and their families. As a result of the difference analysis and path analysis of the questionnaire responses, the following suggestions were obtained. First, age difference is more obvious than sex difference in terms of low salt intentions. For example, older people are healthier than younger people in terms of eating habits and health concerns. Second, the elderly are more likely to practice the low-salt formula when they are provided information on the benefits and effects of the low-salt formula compared to younger ones. Third, systematic efforts are needed to promote a culture that emphasizes the health benefits of a low salt diet rather than providing piecemeal information on the advantages and effects of a low salt diet.

• Journal of The Korean Association For Science Education
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• v.24 no.3
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• pp.544-555
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• 2004

This study examined the conception types of high school students, chemistry teachers, and pre-service teachers about the salt bridge in Daniel cell by a questionnaire and follow-up interviews. High school chemistry II textbooks were analyzed for finding the cause of the understanding difficulties of the teachers and students. Pre-service teachers' thoughts examined for the problems of pre-service teacher programs. From the analysis, it was found that teachers only thought that the role of salt bridge is for ion movement of two solutions involving electrodes. But they didn't have the conception that salt bridge has a roll of connection a circuit. This result was similar to students' and pre-service teachers' results. It was possible that insufficient and different explanations of the textbooks were attributed the teachers' and students' conceptual difficulties.

• Journal of Microbiology
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• v.44 no.4
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• pp.369-374
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• 2006

To investigate the mechanism of salt tolerance of gram-positive moderately halophilic bacteria, two-dimensional gel electrophoresis (2-D PAGE) was employed to achieve high resolution maps of proteins of Halobacillus dabanensis $D-8^T$. Approximately 700 spots of proteins were identified from these 2-D PAGE maps. The majority of these proteins had molecular weights between 17.5 and 66 kDa, and most of them were distributed between the isoelectric points (pI) 4.0 and 5.9. Some protein spots were distributed in the more acidic region of the 2-D gel (pI <4.0). This pattern indicated that a number of proteins in the strain $D-8^T$ are acidic. To understand the adaptation mechanisms of moderately halophilic bacteria in response to sudden environmental changes, differential protein profiles of this strain were investigated by 2-D PAGE and $Imagemaster^{TM}$ 2D Platinum software after the cells were subjected to salt shock of 1 to 25% salinity for 5 and 50 min. Analysis showed 59 proteins with an altered level of expression as the result of the exposure to salt shock. Eighteen proteins had increased expression, S proteins were induced, and the expression of 33 proteins was down-regulated. Eight of the up-regulated proteins were identified using MALDI-TOF/MS and MASCOT, and were similar to proteins involved in signal transduction, proteins participating in energy metabolism pathways and proteins involved in stress.

• Fisheries and Aquatic Sciences
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• v.5 no.1
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• pp.48-53
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• 2002

The HACCP (hazard analysis critical control point) concept becomes an important aspect of Good Manufacturing Practices (GMP) in safe food production. The HACCP plan was developed with food safety objective. The authors already carried out hazards analysis on Changran Jeotgal manufacturing process in a previous report. In this study we developed a HACCP plan on the manufacturing process of Changran Jeotgal. We could decide two CCPs those were salt concentration and eliminations of foreign materials before packaging. Foreign materials should be certainly checked out with laser detector just before packaging. Salt should be maintained more than $8\%$ to inhibit pathogenic bacteria in end product. On the Jeotgal process free water is removed after salting and Jeotgal is seasoned with several subsidiary materials such as com syrup. In result end products have $8\%$ salt with water activity 0.82. Most bacteria are inhibited but some can live in this condition. Materials on the working may be contaminate by pathogens, chemicals or physical hazards. It will be decreased by SSOP (standard sanitary operating program). The SSOP needed in Jeotgal plants is nearly same as other general food manufacturing plants but essential to fulfill HACCP program.

• Membrane and Water Treatment
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• v.9 no.6
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• pp.435-445
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• 2018

In this work, desalination experiments were performed on vacuum membrane distillation (VMD). Process parameters such as feed flow rate, vacuum degree on permeate side, feed bulk temperature and feed salt concentration were optimized using sensitivity analysis and Taguchi method. The optimum values of process parameters were found to be 2 lpm of feed flow rate, $60^{\circ}C$ of feed bulk temperature, 5.5 kPa of permeate-side pressure and 5000 ppm of salt concentration. The permeate flux at these conditions was obtained as $26.6kg/m^2{\cdot}hr$. The rejection of salt in permeate was found to be 99.7%. The percent contribution of various process parameters using ANOVA results indicated that the most important parameter is feed bulk temperature with its contribution of 95%. The ANOVA results indicate that the percent contribution of permeate pressure gets increased to 5.384% in the range of 2 to 7 kPa as compared to 0.045% in the range of 5.5 to 7 kPa.

• Geophysics and Geophysical Exploration
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• v.6 no.4
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• pp.207-214
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• 2003

To analyze soil properties with depth in rice field, we compared resistivity distributions obtained from soil analysis with one dimensional inversion of small loop electromagnetic (EM) data. Although it didn't show consistency exactly between the two resistivity distributions, low resistivity zones in soil analysis, appeared to agree with low resistivity zones in EM result. Therefore, small loop EM method can be applied to obtain rapidly the soil properties such as salt accumulation in a rice field. If research on soil property and EM responses of unsaturated zone would be conducted consistently, small loop EM method can be used effectively to detect salt accumulated zone in agricultural area.

• Nuclear Engineering and Technology
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• v.56 no.2
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• pp.762-769
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• 2024

The TMSR-SF0 simulator is an integral effect thermal-hydraulic experimental system for the development of thorium molten salt reactor (TMSR) program in China. The simulator has two heat transport loops with liquid FLiNaK. In literature, the 95% level confidence uncertainties of the thermophysical properties of FLiNaK are recommended, and the uncertainties of density, heat capacity, thermal conductivity and viscosity are ±2%, ±10, ±10% and ±10% respectively. In order to investigate the effects of thermophysical properties uncertainties on the molten salt heat transport system, the uncertainty and sensitivity analysis of the heat transfer characteristics of the simulator system are carried out on a RELAP5 model. The uncertainties of thermophysical properties are incorporated in simulation model and the Monte Carlo sampling method is used to propagate the input uncertainties through the model. The simulation results indicate that the uncertainty propagated to core outlet temperature is about ±10 ℃ with a confidence level of 95% in a steady-state operation condition. The result should be noted in the design, operation and code validation of molten salt reactor. In addition, more experimental data is necessary for quantifying the uncertainty of thermophysical properties of molten salts.

• Journal of Life Science
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• v.34 no.8
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• pp.531-539
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• 2024

Biogenic amines in food, produced through amino acid decarboxylation, can cause allergies, digestive issues, and neurological symptoms. Recently, various studies have been conducted to reduce the levels of biogenic amines in food. This study analyzes the impact of salt concentration in Ganjang on microbial diversity and biogenic amine production. Results show a statistically significant correlation between salt concentration in Ganjang and species richness and species abundance indices. Although the alpha-diversity index did not significantly correlate with biogenic amine levels, higher salt concentration resulted in a statistically significant decrease in histamine and tyramine levels. An analysis of the correlation between microbial distribution and biogenic amines based on the salt concentration in Ganjang revealed that the distribution of Lactobacillus sp. and Bacteroides sp. increased as the salt concentration increased while the levels of biogenic amines decreased. On the other hand, the distribution of Tetragenococcus sp., Chromohalobacter sp., and Halomonas sp. decreased with increasing salt concentration, accompanied by an increase in biogenic amine levels. The results of this study suggest that within the salt concentration ranges in Ganjang, an increase in salt concentration is associated with an increase in the distribution of Lactobacillus sp., Bacteroides sp., Streptococcus gallolyticus, and Pseudomonas sp. This increase in microbial distribution is presumed to be related to a reduction in biogenic amine production or an enhancement in biogenic amine degradation.