• 한국세라믹학회지
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• 제45권12호
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• pp.845-850
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• 2008

Hydrated sodium silicate was synthesized by hydrothermal reaction using anhydrous sodium silicate. The optimum additions of water was 25wt% to make hydrated sodium silicate with homogeneous and purposed water contents. Porous ceramics with homogeneous microstructure and spherical closed pore can be fabricated by elimination of the large pores(a few mm in size) which was formed during first heat treatment through the decomposition of water. Spherical closed pore was formed above $600^{\circ}C$ and the pore size was increased with increasing second heat treatment temperature due to growth of pores. The size of spherical closed pore was varied from 35 to $233\;{\mu}m$ and specific gravity was varied from 0.2 to 1.02 depending on the combinations of the first and second heat treatment temperature.

• Fisheries and Aquatic Sciences
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• 제3권2호
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• pp.151-155
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• 2000

Phaeodactylum tricornutum (Bacillariophyceae) is a marine diatom which has been supplied as a food of bivalves. In this study, growth responses of P. tricornutum to some nitrogen sources and sodium were investigated by measuring cell number and contents of chlorophyll a in culture. In medium with nitrogen and sodium, brisk cell division occurred and maximum growth rate was respectively found in the medium with 150 mg/l of nitrate and 10 mg/l of ammonium and urea. At 10-500 mg/l ammonium and urea and 200-500 mg/l nitrate, specific growth rate decreased slightly. However, no cell division observed in sodium-deficient medium, regardless of presence or absence of nitrogen. This suggests that sodium is required for the nitrogen uptake of P. tricornutum, resulting nitrogen uptake leading to cell division. Also the upper limits of ammonium and nitrate for the growth of P. tricornutum seem to be 10 mg/l and 500 mg/l, respectively.

• Journal of Nutrition and Health
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• 제26권9호
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• pp.1098-1109
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• 1993

The purpose of this study was to investigate macro-mineral contents in human milk longitudinally from 2 days to 12 weeks postpartum. Milk samples were collected from 34 healthy lactating women. Calcium, Phosphorus, magnesium, sodium and potassium were analyzed. Concentrations of the minerals except for magnesium differed significantly within the lactation period. The levels of sodium and potassium declined linearly over the first 12 weeks of lactation, but that of phosphorus increased. Statistically significant quadratic trends were observed in phosphorus and sodium concentrations. There was no significant correlation between maternal age and mineral concentrations throughout the lactations period. In addition, no significant differences were found between the primipara and the multipara for mineral concentrations in human milk. Mineral intake of lactating women did not affect the individual mineral concentrations of milk. However, the protein and fat intake of lactating women had a significant correlation with sodium and potassium concentrations. The following four pairs of minerals : potassium and calcium, potassium and phosphorus, sodium and magnesium, and calcium and phosphorus showed a positive correlation with each other in human milk.

• 한국축산식품학회지
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• 제40권4호
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• pp.636-648
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• 2020

This study investigated the effects of the addition levels of white kimchi powder and acerola juice powder, as natural sources of sodium nitrite and sodium ascorbate, on the quality of cooked ground pork products. Freeze-dried white kimchi powder was prepared and used after fermentation for 2 wk. Six treatments were included: control (100 ppm sodium nitrite and 500 ppm sodium ascorbate), treatment 1 (0.2% white kimchi powder, 0.02 % starter culture, and 0.1% acerola juice powder), treatment 2 (0.2% white kimchi powder, 0.02% starter culture, and 0.2% acerola juice powder), treatment 3 (0.4% white kimchi powder, 0.04% starter culture, and 0.1% acerola juice powder), treatment 4 (0.4% white kimchi powder, 0.04% starter culture, and 0.2% acerola juice powder), and treatment 5 (0.4% celery powder, 0.04% starter culture, and 0.2% acerola juice powder). The pH values were decreased (p<0.05) because of lower pH of acerola juice powder, resulting in lower cooking yields (p<0.05) in these treatments. CIE L* and CIE a* values of indirectly cured meat products were not different (p>0.05) from the sodium nitrite-added control. However, indirectly cured meat products showed lower (p<0.05) residual nitrite contents, but higher (p<0.05) nitrosyl hemochrome contents and cure efficiency than the control. Treatments 2 and 4 had higher (p<0.05) total pigment contents and lipid oxidation than the control. This study indicates that white kimchi powder coupled with acerola juice powder has substantial potential to substitute synthetic nitrite to naturally cured meat products, which could be favored by consumers seeking clean label products.

• 한국의류학회지
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• 제30권11호
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• pp.1581-1588
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• 2006

The effects of removal of lignin or hemicellulose on the cottonizing and pulping characteristics of kenaf fiber were studied by comparing the conditions of non-cellulosic material contents, fiber lengths and dyeability. And the effects of lignin or hemicellulose on dyeability of the kenaf fiber using CI Direct Green 26 and CI Direct Red 81 were investigated. The results were as follows. The lignin contents decreased and the kenaf fiber became shorter and finer as the reaction time with sodium chlorite increased. The hemicellulose could be removed by treating sodium hydroxide solution to the fiber from which the lignin partly removed. The 80% of hemicellulose could be removed by 5% of sodium hydroxide solution in 5 minutes. But if lignin were not removed at all, hemicellulose could not be removed. The fiber lengths proper for apparel were obtained after treating sodium chlorite for 10-20 minutes and those for pulping were obtained after treating sodium chlorite for 40 minutes. The kenaf fibers from which lignin and hemicellulose partly removed were dyed with CI Direct Green 26 and CI Direct Red 81. Their dyeability increased as the removal rates of lignin increased. The ${\Delta}E$ values of kenaf fiber dyed with CI Direct Green 26 were lower than CI Direct Red 81.

• 한국식품영양과학회지
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• 제38권8호
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• pp.1037-1041
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• 2009

아연의 공급수준이 다량 무기질 함량에 미치는 영향을 알아보기 위해 흰쥐를 대상으로 아연을 결핍, 적정, 과잉 수준으로 공급하여 혈청 및 조직의 칼슘, 마그네슘, 나트륨, 칼륨함량을 분석하였다. 아연 공급수준을 달리했을 때 혈청의 다량 무기질 함량은 유의적인 차이를 보이지 않았지만 간과 비장에 영향을 주는 것으로 나타났다. 특히 아연의 결핍은 간의 칼슘 함량을 감소시키는 영향을 주었고, 아연의 과잉은 비장 마그네슘과 칼륨 함량을 감소시키는 결과를 나타냈다. 결론적으로 아연의 결핍과 과잉이 간과 비장의 다량 무기질함량에 영향을 주는 것으로 나타났는데, 특히 아연의 결핍이 더 많은 조직 내 무기질 함량 변화를 가져왔다. 그러나 본 연구에서는 아연의 결핍수준을 적정수준의 50%, 그리고 과잉을 200%로 설정하였으나 앞으로 좀 더 세분화된 아연의 결핍과 과잉 수준에 대한 체계적인 연구가 필요하다고 사료 된다.

• 생물환경조절학회지
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• 제15권1호
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• pp.21-34
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• 2006

This research was conducted to determine the plant growth and nutrient contents of potted chrysanthemum 'Lima Honey' as influenced by application rate of fused superphosphate (FSSP) in three root media, peatmoss+vermiculite (1:1, v/v; PV), peatmoss+composted rice hall (1:1, v/v; PR), and peatmoss+composted pine bark (1:1, v/v; PB). All root media contained polyacrylic acid sodium salt at a rate of $4.5g L^{-1}$. The treatment of $1.4g L^{-1}$ in PV and those of $0.7g L^{-1}$ in PR and PB had the greatest fresh and dry weights in each root medium at both 43 and 80 days after transplanting. Elevated application rates of FSPP increased tissue contents of N, P, and K at both 43 and 80 days after transplanting in PV medium. However, the differences in tissue contents of N, P and K in PR medium were less significant among treatments of FSPP. The pre-planting FSPP also less affected the tissue contents of nutrients at 80 days after transplanting as compared to those at 43 days after transplanting. Elevated application rates of FSPP in PV medium increased EC and the concentrations of $NO_3,\;P_2O_5$, K, Ca, and Mg in soil solution of root media at 43 days after transplanting. The EC in PV medium at 80 days after transplanting was higher than that at 43 days after transplanting. The EC in all root media at 80 days after transplanting was not different among treatments of FSPP.

• 한국세라믹학회지
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• 제13권1호
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• pp.20-24
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• 1976

These are many kinds of self-hardening methods for sand mold using sodium silicate. When sodium silicate solution is mixed with calcium-orthosilicate powder hardening reaction occurs, which is based for self-hardening method at high temperature. The high temperature strength and resicual strength of mold are related to the mole ratio of sodium silicate and the contents of calcium-orthosilicate powder. The results obtained in this study were as follows: 1) The high temperature strength of mold was maximum at about $600^{\circ}C$, and at higher temperature showed lower value on the contrary. 2) The high temperature strength of mold was increased by increasing the amount of sodium silicate having lower mole ratio and high concentration. 3) The residual strength of mold was reduced by increasing the mole ratio of sodium silicate and increasing the concentration of calcium-orthosilicate.

• 한국환경과학회지
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• 제28권11호
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• pp.943-950
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• 2019

The purpose of this study was to probe the influences of NaF oral administration on a dose-effect relationship between fluoride levels of serum enzyme activity such as alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) in rats fed experimental diets for 5 weeks. All groups increased the activity of serum ALP, AST, ALT, and LDH levels with increasing NaF. In addition the fluoride levels of serum and organ tissues (liver, brain, heart, lung, kidney) in oral NaF groups (NF3~NF50) were significantly increased by adding sodium fluoride in comparison with normal diet group (ND) (p<0.05). These results, a high concentration of sodium fluoride was determined that the toxicity to various organ tissues.

• Journal of Nutrition and Health
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• 제10권1호
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• pp.38-43
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• 1977

This study was designed to find out the status of low sodium diet in 27 hospitals located in Seoul and rural areas. The study was conducted from the beginning of June, 1976 to October, 1976. The differences in Na, protein and calorie contents between the hospitals in Seoul an ones in rural areas, and between the medical college attached hospitals and general ones, were compared by means of t-test. Correlation coefficient were made among Na, protein and calorie. In order to find out which food group is the major source of Na in the diet, six food groups were divided and Na content in each was calculated. The results showed that average daily Na intake of 27 hospitals was 2,382mg which is regarded as mild restriction. Average daily protein and calorie intakes were 94gm and 2,438 cal respectively. About 60% of hospitals restricted sodium at mild level $(2,300mg{\sim}4,600mg)$ and 33% at moderate $(1,000mg{\sim}2,300mg)$ and only 7% of the subjects were Planning strict sodium restriction $(250mg{\sim}500mg)$ There was statistically significant differences in Na contents between Seoul and rural areas. But no significant difference was found between medical college attached hospitals and general ones. The correlation between the average daily intakes of Na and protein was found not to be significant but protein and calorie intakes were related each other. When the total sodium intakes divided into six groups, about 74% were supplied by condiments (Food group 6th).