• Journal of Mechanical Science and Technology
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• 제15권11호
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• pp.1533-1540
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• 2001

A high-temperature sodium stainless steel heat pipe was fabricated and its performance has been investigated. The working fluid was sodium and it was sealed inside a straight tube container made of stainless steel. The amount of sodium occupied approximately 20% of the total volume of the heat pipe and its weight was 65.7gram. The length of a stainless steel container is 1002mm and its outside diameter is 25.4mm. Performance tests were carried out in a room air condition under a free convective environment and the measured temperatures are presented. The start-up behavior of the heat pipe from a frozen state was investigated for various heat input values between 600W and 1205W. In steady state, axial temperature distributions of a heat pipe were measured and its heat transfer rates were estimated in the range of vapor temperature from 50$0^{\circ}C$ to 63$0^{\circ}C$. It is found that there are small temperature differences in the vapor core along the axial direction of a sodium heat pipe for the high operating temperatures. But for the range of low operating temperatures there are large temperature drops along the vapor core region of a sodium heat pipe, because a small vapor pressure drop makes a large temperature drop. The transition temperature was reached more rapidly in the cases of high heat input rate for the sodium heat pipe.

• Nuclear Engineering and Technology
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• 제55권4호
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• pp.1468-1475
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• 2023

Enhancement of wear resistance of components used in fast reactors is necessary for long service life of the components. Plasma nitriding is a promising surface modification technology to impart high hardness and improved wear resistance of various steel components. This study discusses the characterization of chrome nitrided SS316L casing ring used in secondary sodium pump of fast breeder reactor and its stability under long term sodium exposure. Microstructural and hardness analysis showed that stress relieved component could be chrome nitrided successfully to a thickness of about 100 ㎛. Assessment of in-sodium performance of the chrome nitrided casing ring subjected to long term exposure up to 5000h at 550℃, showed retention of chrome nitrided layer with a case depth almost similar to that before sodium exposure. A slight decrease in the hardness was observed due to prolonged high temperature sodium exposure. Tribological studies indicate very low coefficient of friction indicating the retention of good wear resistance of the coating even after long term sodium exposure.

• 한국조경학회지
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• 제30권5호
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• pp.107-115
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• 2002

This study was carried out to compare artificial soil formulated by blending calcined clay and coconut peat with perlite, then to evaluate this soil as a perlite substitute for use as an artificial planting medium. To achieve this, a determination of the physico-chemical properties and it's effect on plant growth were conducted by comparing those with large perlite grains and small grains. The results are summarized as follows: 1) The bulk density was 0.41g/㎤. This density was lower than that of field soil, but higher than that of large perlite grain(0.23g/㎤) and small grain(0.25g/㎤). The porosity, field capacity, and saturated hydraulic conductivity were 71.3%, 49.2%, and 3.8$\times$10-2cm/s, respectively. The air-permeability, water holding capacity, and drainage were better than or equal to that both large and small perlite grain. 2) It was near-neutral in reaction(pH=6.6). It had a high organic carbon content(65.8g/kg) and a low available phosphoric acid content(84.7mg/kg). It was similar to crop soil in cation exchange capacity(11.4cmol/kg). It had a low exchangeable calcium content(0.71cmol/kg), a low exchangeable magnesium content(0.68cmol/kg), a high exchangeable potassium content(2.54cmol/kg), and a high exchangeable sodium content(1.12cmol/kg). Except for the exchangeable potassium and sodium content, the chemical properties were better than or equal to both large and small grain perlite. The excessive exchangeable potassium or sodium content will inhibit plant growth. 3) In Experiment 1, the plant growth tended to be higher compared to that of large and small perlite gains. But in Experiment 2, it tended to be lower. This might be linked to the excessive exchangeable potassium or sodium content. 4) It could be considered as a renewable perlite substitute for greening of artificial soil. But, it would be necessary to leach the excessive exchangeable potassium or sodium to avoid the risk of inhibiting plant growth.

• 폴리머
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• 제27권6호
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• pp.583-588
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• 2003

저분자 키토산과 저분자 알진산 나트륨을 삼산화황-피리딘 복합체와 황산화 반응시켜 황산화 키토산과 황산화 알진산 나트륨을 합성하였다. 황산화 반응에서 삼산화황-피리딘 복합체/다당류의 무게비율이 1:5일 때 황산화도가 각각 2.75와 2.53으로 가장 큰 값을 나타내었다. 합성한 황산화 키토산 및 황산화 알진산의 혈액에 대한 항응고 효과 및 활성트롬보 플라스틴 측정 시험을 행한 결과 분자량이 8.0${\times}$$10^3$ Da일 때 항응고 효과가 가장 우수하였고 황산화 키토산과 황산화 알진산 나트륨을 무게비율 1:1 로 혼합하였을 때 헤파린에 비하여 91% 정도로 항응고 활성이 가장 좋았다. 활성트롬보 플라스틴 측정시험에서도 황산화 키토산과 황산화 알진산 나트륨의 무게비율이 1:1일 경우에 항응고 활성이 헤파린에 비하여 84%로 가장 좋았다.

• 한국식생활문화학회지
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• 제34권5호
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• pp.620-628
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• 2019

To investigate Oiji (traditional Korean cucumber pickles) with reduced sodium content based on the use of saline foods as a salt substitute, Oiji was prepared using glasswort powder (Salicornia herbacea L.), and its physicochemical properties and sensory evaluation were examined. The moisture content of Oiji was shown to be higher in those to which glasswort powder had been added compared to the control without addition of glasswort powder, and Oiji with 40% glasswort powder substitute showed the highest pH and lowest acidity, resulting in slow progression of fermentation. The salinity of Oiji among those containing glasswort powder substitute was significantly higher with increasing level of glasswort powder. The sodium content of Oiji was significantly reduced as addition of glasswort powder increased. The L value of Oiji decreased with increased addition of glasswort powder, whereas the a value was highest in the control. The hardness of Oiji was higher in the control than in Oiji containing glasswort powder. Taste acceptance was highest for Oiji with 20% glasswort powder substitute, whereas acceptance of appearance was higher for Oiji with 10% glasswort powder substitute. Flavor and texture acceptance was higher for the control. In the attribute difference test, significant differences were found in brownness, off-flavor, salty taste, and sourness. Based on the findings, 10-20% substitution of salt with glasswort powder did not significantly lower overall acceptance compared to the control while salinity of Oiji was maintained. Therefore, the potential production of low-sodium Oiji has been verified.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.323-328
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• 2002

Rapid set accelerators are widely used in tunnel construction, however quality criteria of and dosage are not well established. The density and solid content of admixtures, setting time and compressive strength of paste and mortar with admixtures were investigated to establish the quality criteria. While the early strength of mortar with sodium-silicate, sodium-aluminate and calcium aluminate type admixtures that have high alkali content are very high, but long-term strength are low. Aggregates of shotcrete has to be carefully selected. Sodium-silicate type admixture need longer setting time than the others.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2000년도 학술대회논문집
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• pp.107-110
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• 2000

This paper deals with the design of the electronic ballast for high pressure sodium lamp, which consists of the ignitor and the resonant converter for driving the lamp. Also it contains PFC(Power Factor Controller) to improve such as power factor, low distortion etc. In this paper, we design the electronic ballast for the 150 watt high pressure sodium lamp.

• 한국축산식품학회지
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• 제30권2호
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• pp.298-304
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• 2010

본 연구는 돈육 목심 세절육에서 식염함량의 저하에 따른 기능성 및 조직감을 분석하였고, 저염 육제품의 transglutaminase(TG)와 두 종류의 인산염(sodium polyphosphate, STPP; sodium pyrophosphate, SPP)을 첨가하여 저염 돈육제품의 물성을 증진시키기 위해 수행되었다. 식염함량에 따른 목심 균질육의 특성을 평가한 실험 1에서는 식염함량이 증가함에 따라 지방 함량, 명도 그리고 황색도는 감소한(p<0.05), 반면, 수분 함량과 가열수율은 증가하였다(p<0.05). 실험 1의 결과에 따라 1.0% 식염함량을 저염조건으로 저염 돈육 목심 세절육에서 TG와 두 종류의 인산염(STPP, SPP)의 단일 혹은 복합첨가 효과를 조사하였다(실험2). 실험 2에서는 인산염을 첨가함에 따라 pH가 유의적으로 상승하였으며(p<0.05), 특히 SPP가 단일 또는 STPP와 혼합하여 첨가된 처리구는 STPP를 단일 첨가한 처리구에 비해 높은 pH값을 보였다(p<0.05). TG와 인산염을 첨가한 처리구들은 대조구 보다는 낮고 인산염 무첨가구 보다는 높은 가열수율의 결과를 나타냈다(p<0.05). 조직감 검사에서는 탄력성 항목에서 SPP를 단일 첨가한 처리구가 대조구보다 높은 값을 나타냈다(p<0.05). 따라서 저염 조건에서 인산염의 첨가를 통한 가열수율의 저하를 보완하고, TG 첨가를 통하여 조직감을 증진시켜 기능성 저염 육제품의 제조가 가능할 것으로 사료된다.

• Journal of Nutrition and Health
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• 제33권6호
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• pp.647-659
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• 2000

o assess the food intake and the sodium and potassium intakes and urinary excretion of preschool children in Pusan and to evaluate the relationship among variables dietary behaviors food and nutrient intake and 24hr urinary sodium and potassium excretion were measured with 97 subjects. The mean sodium and potassium intakes were 1890. 1mg(82,2meq) and 1479.7mg(37.8meq) respectively. The mean potassium intake(p<0.05) and density(p<0.01) were significantly low at the group who had food intake pattern absen of fruit and daily groups. The mean urinary sodium and potassium excretion were 735.3mg(32.0meq) and 418.7mg(10.7meq) respectively. The mean sodium intake(p<0.01) and urinary excretion were 735.3mg(32.0meq) and 418.7mg(10.7meq) respectively. The mean sodium intake(p<0.01) and urinary excretion (p<0.001, p<0.001) energy intake(p<0.01) sodium intake and density (p<0.001, p<0.05) the food number and intake frequency of vegetable group consumed (p<0.01, p<0.01) dietary frequency score(p<0.05) and negative correlations with the food number and frequency of dairy group consumed (p<0.05 p<0.05) The urinary potassium excretion showed positive correlations with height and weight(p<0.05, p<0.01) urine volume and urinary creatinie excretion(p<0.01 p<0.001) potassium intake(p<0.05) food number and intake frequency of dairy group consumed (p<0.05, p<0.001). Based on the results urinary sodium excretion was related to age sodium intake and food intake of vegetable and dairy group and urinary potassium excretion was related to potassium intake and food intake of dairy group. So nutritional education is needed in order to decrease sodium intake especially from food intake of vegetable group when preschool children have less food intake of diary group,.

• 미생물학회지
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• 제21권3호
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• pp.115-126
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• 1983

The results that the effect of 6 detergents on the structural changes and biochemical composition of bacterial membrane of Escherichia coli and Bacillus cereus are as follows ; 1. Population growth of the bacteria was increased in case of the treatment with palmitoyl carnitine and sodium deoxy cholate but was increased in case of the treatment with palmitoyl carnitine and sodium deoxy cholate but was decreased by sodium dodecyl sulfate and palmitoyl choline, in E.coli and was decreased by palmitoyl carnitine and palmitoyl choline at the low concentration, in B. cereus. 2. The electron micrograph showed that cell wall lysis or cell collapse were observed in the treatment of sodium dodecyl sulfate and palmitoyl choline, and also cell wall was condensed by triton X-100 and sodium deoxy cholate, in E.coli. And in B. cereus, endospore formation of the bacteria was stimulated by palmitoyl choline, and cell lysis or structural changes of the membrane were observed in the treatment of sodium dodecyl sulfate, sodium cholate, and triton X-100, respectively. 3. As to the effect of detergent on the biochemical composition of biomembrane, the content of carnitine, in E.coli, and B.cereus, the content of structural protein and phospholipid were decreased by treatment of sodium dodecyl sulfate and structural protein was denatured by palmitoyl choline. 4. The profile of membrane protein revealed that the bacterial membrane were composed of various proteins. By dint of this result, some of membrane proteins were solubilized or changed to small molecules by the treatment of sodium dodecyl sulfate and palmitoyl choline, in E.coli and membrane protein of the biomembrane by treatment of sodium dodecyl sulfate, sodium deoxy cholate, palmitoyl choline, and palmitoyl carnitine were confirmed to be different profile as compared with those of the control, in B. cereus. Therefore, it is suggested that sodium dfodecyl sulfate and palmitoyl choline soulbilized biomembranes or inhibited membrane transport and that palmitoyl carnitine and sodium deoxy cholate were used as an energy source or stimulating the membrane transport, in E.coli. And, it is suggested that all of detergents were inhibited biomembrane synthesis, expet saponin, in B.cereus.