• Nuclear Engineering and Technology
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• v.30 no.6
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• pp.568-580
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• 1998

A sodium-concrete reaction facility with a test chamber of 0.226㎥($\Phi$0.6m$\times$H0.8m) was constructed to carry out experiments of sodium-concrete reaction which might take place in sodium metal fast-breeder reactor Utilizing this facility, several experiments were conducted to closely examine the characteristics of sodium-concrete reactions under different conditions : Sodium mass : 100, 250g ; Sodium temperature : 450, 550, $650^{\circ}C$ ; Concrete age = 30, 45, 50, 90days. Our experiments show that the amount of the H2 generated by sodium-concrete reaction has increased up to its flammable range as the amount of spilled sodium and its temperature have increased. The maximum hydrogen concentration was 31mo1% at the concrete age of 30days, sodium temperature : 55$0^{\circ}C$, and sodium mass : 250g. The major components of sodium-concrete reaction products were also determined as Na$_2$SiO$_3$ and NaAlO$_2$.

• Nuclear Engineering and Technology
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• v.53 no.11
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• pp.3474-3490
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• 2021

Sodium-cooled fast reactor (SFR) is the preferred technology of the generation-IV fast neutron reactor, and its core body mainly uses nuclear-grade 316 stainless steel. In order to prolong the design life of SFRs to 60 years and more, it is necessary to summarize and analyze the anti-corrosion effect of nuclear grade 316 stainless steel in high temperature sodium environment. The research on sodium corrosion of nuclear grade 316 stainless steel is mainly composed of several important factors, including the microstructure of stainless steel (ferrite layer, degradation layer, etc.), the trace chemical elements of stainless steel (Cr, Ni and Mo, etc) and liquid impurity elements in sodium (O, C and N, etc), carburization and mechanical properties of stainless steel, etc. Through summarizing and constructing the sodium corrosion rate equations of nuclear grade 316 stainless steel, the stainless steel loss of thickness can be predicted. By analyzing the effects of temperature, oxygen content in sodium and velocity of sodium on corrosion rate, the basis for establishing integrity evaluation standard of SFR core components with sodium corrosion is provided.

• Nuclear Engineering and Technology
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• v.55 no.4
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• pp.1528-1539
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• 2023

Since the leakage of sodium in an SFR (sodium-cooled fast reactor) causes an explosion upon reaction with air and water, sodium leakages represent an important safety issue. In this study, a novel technique for improving the reliability of sodium leakage detection applying DDVR (dynamic data validation and reconciliation) is proposed and verified to resolve this technical issue. DDVR is an approach that aims to improve the accuracy of a target system in a dynamic state by minimizing random errors, such as from the uncertainty of instruments and the surrounding environment, and by eliminating gross errors, such as instrument failure, miscalibration, or aging, using the spatial redundancy of measurements in a physical model and the reliability information of the instruments. DDVR also makes it possible to estimate the state of unmeasured points. To validate this approach for supporting sodium leakage detection, this study applies experimental data from a sodium leakage detection experiment performed by the Korea Atomic Energy Research Institute. The validation results show that the reliability of sodium leakage detection is improved by cooperation between DDVR and hardware measurements. Based on these findings, technology integrating software and hardware approaches is suggested to improve the reliability of sodium leakage detection by presenting the expected true state of the system.

• Journal of Nutrition and Health
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• v.34 no.7
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• pp.786-796
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• 2001

To assess calcium and sodium and urinary excretion of preschool children in Busan and to evaluate the relationship of intakes of food and nutrient with urinary calcium excretion, calcium and sodium food frequencies of 25 common foods affecting intakes of calcium and sodium per week, nutrient intake by 24hr recall and 24hr urinary calcium and sodium excretion were measured with 97 preschool children. The mean calcium intake was 436.11mg and below RDA. The mean sodium intake was 1890.11mg. The mean urinary calcium and sodium excretion were 42.88mg and 735.25mg respectivery. The mean urinary calcium/creatinine ratio was 0.20. The urinary calcium excretion showed positive significant correlations with weight, intake frequency of pizza consumed per week and urinary sodium excretion (p<0.05, p<0.05, p<0.001). The urinary calcium excretion per milligram of creatinine showed positive significant correlations with intake frequencies of pizza and common squid consumed per week(p<0.01, p<0.05) and negative correlation with intake frequencies of pizza and common squid consumed per week(p<0.01, p<0.05) and negative correlation with age(p<0.05). No significant relations were found between urinary calcium and intakes of calcium, protein and phosphorus. Urinary sodium was found to be the most important determinant of urinary calcium excretion. Intake frequency of pizza consumed per week was found to be the most important determinant of urinary calcium excretion per milligram of creatinine. Based on the results, urinary calcium excretion was related to intake frequency of pizza consumed per week and urinary sodium excretion. Low calcium intake and increase of calcium loss in the urine potentiated by sodium intake during growth may reduce peak bone mass. So nutritional education is needed in order to increase calcium intake and decrease sodium intake, especially from food like pizza.

• Nutrition Research and Practice
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• v.6 no.3
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• pp.232-237
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• 2012

This study was done to explore the effect of Korean women's salt usage behavior on their sodium intake and excretion according to aging. Dietary sodium intake and salt usage behavior were analyzed to compare the difference between young and middle-aged women. One hundred fifty six young women and 77 middle-aged women without hypertension or any current medication were recruited. Body mass index, waist hip ratio, blood pressure were measured from each subject. Salt usage behaviors were surveyed with questionnaire, sodium intake with 24-hr recall method, and sodium excretion with spot urine. Middle-aged women were more obese than young women according to body mass index and waist hip ratio. Blood pressure was significantly higher for the middle-aged. Young women consumed more fats and middle-aged women more carbohydrates. Middle-aged women consumed more sodium and potassium, and excreted more sodium. Among questionnaire items, kimchi, soup or pot stew, or salted vegetables were found to be related with high sodium diet. Salted vegetables and salted nuts and potato chips were significantly correlated with young women's high sodium diet, while soy sauce on fried food, kimchi, salted vegetables accounted for middle-aged women's high sodium diet. With these results, we concluded that middle-aged women consumed more carbohydrates, less fat, and more sodium and potassium than young women. Middle-aged women frequently choose kimchi, soup or pot stew, or salted vegetables, and they contribute to high sodium intake. We recommend to choose low-salt kimchi, less soup or pot stew, and more fresh vegetables for lower sodium diet.

• Nutrition Research and Practice
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• v.15 no.3
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• pp.382-395
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• 2021

BACKGROUND/OBJECTIVES: Excess intake of dietary sodium, either directly or indirectly, increases the risk of several diseases, including cardio-cerebral vascular diseases such as stroke and hypertension. Excessive sodium intake and increased prevalence of hypertension have emerged as major issues worldwide. Therefore, the present study evaluated the recent trends in dietary sodium intake and the food sources of sodium intake in the Korean population using the Korea National Health and Nutrition Examination Survey (KNHANES, 2013-2017) data. SUBJECTS/METHODS: This study used the one-day 24-h recall dietary intake survey data from the 2013-2017 KNHANES to determine the average daily sodium intake by sex and age and the main dishes and food groups contributing to the dietary sodium intake. RESULTS: The mean sodium intake range was 3,477.2-3,889.6 mg/day during 2013-2017. The major food groups contributing to sodium intake were seasonings (1,597.5-1,870.5 mg/day), vegetables (680.4-756.7 mg/day), and cereal and grains (573.2-609.4 mg/day). Noodles and dumplings (536.7-573.2 mg/day), kimchi (487.3-539.6 mg/day), and soups (367.6-428.9 mg/day) were the top three dish groups that contributed to the sodium intake. In these dishes, the major sources of sodium intake were ramyeon (age groups 10-18 and 19-29 yrs), baechukimchi (age groups 40-49 and 50-59 yrs) and doenjang-kuk (age groups 60-69 and ≥ 70 yrs), respectively. CONCLUSIONS: In summary, reducing the consumption of soups and kimchi is an effective way to reduce sodium intake. Personalized nutrition education on dietary sodium intake management is required because of the different food sources contributing to the sodium intake according to the subjects' age.

• Journal of Nutrition and Health
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• v.23 no.1
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• pp.37-43
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• 1990

본 연구는 산업체 근로자의 Sodium섭취 실태를 파악하므로서 효율적인 식사관리와 건강관리의 기초자료를 얻고자 서울 시내 H타이어 공장에 근무하는 건강한 성인남자 40명을 대상으로 3일간의 식사분석과 뇨분석을 행한 것이다. 열량섭취는 1일 평균 3,185$\pm$813(mean$\pm$SD)kcal 였으며 영양소 섭취량은 당질이 541.8$\pm$144.5g, 단백질이 127.2$\pm$61.0g, 지방질이 56.8$\pm$42.7g이었고 총 열량의 68%, 16%, 16%를 차지했다. 식사분석에 의한 Sodium섭취량은 225.3$\pm$75.2mEq(13.2$\pm$4.4g Nacl)였으며 뇨중의 Sodium 배설량은 232.8$\pm$63.8mEq(13.7$\pm$3.5g NaCl)였다. 주요 음식의 1회 순섭취량에 대한 Sodium섭취는 국종류에서 가장 많았으며 1일 섭취하는 식사의 Sodium분포는 밥에서 6.9%, 국 35.7%, 반찬류 49.4%, 식탁에서 사용하는 조미료로서 5.1%, 간식에서 2.9%이었다. 당질섭취와 Sodium섭취, 단백질 섭취와 Sodium섭취 사이에는 강한 양의 상관을 보였다.

• Journal of Environmental Science International
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• v.9 no.3
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• pp.209-214
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• 2000

The preventive effects of sodium molybdate on the acute toxicity of lead were studied by investigating tissue accumulation of lead, changes of nerve conduction velocity and concentrations of metabolites related to function of sciatic nerve in rats treated with lead, sodium molybdate and both, respectively. In lead-intoxicated rat, the conduction velocity, myo-inositol concentration and $Na^{+}/K^{+}$ ATPase activity of sciatic nerve were decreased by about 33 %, 48 % and 58 %, respectively. However, sodium molybdate treatment significantly normalized the conduction velocity, $Na^{+}/K^{+}$ ATPase activity and myo-inositol concentration of sciatic nerve in lead-intoxicated rat. Also, sodium molybdate treatment decreased the contents of lead in blood and sciatic nerve through promotion of urinary excretion of lead. But sodium molybdate treatment did not affect the glucose concentration in sciatic nerve. These results suggest that sodium molybdate prevented peripheral neuropathy not only by reducing lead contents in sciatic nerve and blood, but also by enhancing $Na^{+}/K^{+}$ ATPase activity in sciatic nerve.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.165.1-165
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• 2003

복숭아는 절단 후 표면의 갈변현상이나 당도 저하 등이 발생하여 신선편이 식품화시 품질열화의 원인이 된다. 이에 본 실험에서는 일차적으로 유명 품종에 한해 fresh-cut peach의 anti-browning chemicals를 탐색하고, 그 결과를 통해 이차적으로 효과가 우수한 chemicals를 선정하여 백향 품종에 농도별 실험을 행하였다. 유명 품종을 반으로 절단한 후 제핵하고 8등분하여 1% ascorbic acid, 1% sodium chloride, 1% sodium ascorbate monohydrate, 0.005% 4-hexylresorcinol 용액에 3분간 침지시켜 draining한 후, PP tray에 담고 PP film으로 밀봉하여 4$^{\circ}C$에서 저장하였다. 가용성고형분은 to sodium chloride 용액으로 처리한 구에서 가장 높게 유지되었고 pH 또한 비교적 일정하였으며, 1% sodium chloride과 1% sodium ascorbate monohydrate 용액으로 처리한 구의 L값이 높게 유지되었다. 따라서 fresh-cut peach에 효과가 있는 것으로 판단되는 이 두 chemicals의 농도별 용액을 조제하여 같은 방법으로 백향 품종의 갈변저해제로서 처리하였다. 그 결과 2% sodium chloride의 가용성고형분이 가장 높게 유지되었으며 2% sodium ascorbate monohydrate 다음으로 2% sodium chloride 용액 처리구의 L값의 변화 양상이 가장 양호한 것으로 나타났다. 따라서 종합적으로 살펴볼 때, 2% sodium chloride 용액의 처리가 fresh-cut peach의 품질 변화 억제에 적합하다고 판단되었다.

• Journal of the FoodService Safety
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• v.2 no.1
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• pp.1-9
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• 2021

To determine the sodium content of meals provided by foodservice institution, 540 different menus were collected by their serving portion and categorized into nine food groups and three different foodservice types (office, industry, school). Each were evaluated by each sodium evaluation method. All nine categories of food type showed higher content of sodium than listed in the 'nutrition assessment program (Can-Pro 4.0)', when assessed with a salimeter. From the 9 food types, 6 types, excluding 'Korean pancakes', 'Kimchi/pickled food' and 'a la carte', showed significantly higher sodium content on the salimeter than shown in the 'nutrition assessment program (Can-Pro 4.0)' (p<0.001). Also in assessing sodium content per serving, 'soup and stews' and 'a la carte' menus had significantly higher sodium content than other food types (p<0.001). The results compared by foodservice types showed dishes served in 'Industries' had significantly higher daily sodium content than those served in 'offices' and 'schools'.