• 대한화학회지
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• 제44권6호
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• pp.526-532
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• 2000

사용후핵연료에 미량 함유되어 있는 루테늄 분석법을 개발하기 위하여 양이온교환법을 이용한 분리 조건을 조사하였다. 산분해 장치를 사용하여 9:1 몰비의 혼합산($HCl-HNO_3$)으로 루테늄 시료를 용해시켰다. 염산 용액에서 루테늄의 흡수스펙트럼과 이온교환 거동 조사를 통해 분리에 관련된 루테늄의 화학종을 제시하였다. 미량의 루테늄이 함유되어 있는 우라늄 용액을 양이온교환수지(AG 50W ${\times}$ 8, 100~200 mesh) 분리관(0.7 ${\times}$ 8.0 cm)에 넣고 0.5 M 염산으로 루테늄을 용리시켰다. 모의 사용후핵연료에 확립된 루테늄 분리방법을 적용하고 유도결합 플라스마 원자방출분광분석법으로 분석한 결과 루테늄 회수율은 98.5%이었다.

• 폴리머
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• 제32권6호
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• pp.509-515
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• 2008

Acrylic acid 단량체를 방사선 동시조사법으로 폴리프로필렌 멜트 블로운 섬유에 그래프트 반응시켜 PPmb-g-AAc 공중합체를 제조한 후 아민화 반응을 통하여 아민형 이온교환섬유를 합성하였다. 공중합체의 그래프트율은 acrylic acid 단량체의 농도와 총조사선량이 증가할수록 증가하였으며 acrylic acid 단량체의 농도와 총조사선량이 20 v/v%, 4 kGy일 때 140%로 최대치를 나타내었다. Mohr's salt의 최적농도는 $5.0\times10^{-3}$ M로 나타났다. 아민화율은 그래프트율이 증가할수록 증가하여 140%일 때 78.8%로 나타났다. 아민화한 PPmb-g-AAc 공중합체의 함수율은 기재보다 1.5배 정도 높게 나타났으며 이온교환용량은 7.3 meq/g으로 상용 이온교환섬유보다 2$\sim$3배 정도 높게 나타내었다. 합성한 APPmb-g-AAc의 BET 측정결과 PPmb, PPmb-g-AAc 및 APPmb-g-AAc 섬유의 경우 공극의 크기와 비표면적이 각각 $366.1\;{\AA},\;3.71m^2/g$와 $143.3\;{\AA},\;4.94m^2/g$ 및 $40.97\;{\AA},\;8.98m^2/g$로 공극의 크기는 감소하고 비 표면적이 증가하는 경향을 보였다.

• Ocean and Polar Research
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• 제31권2호
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• pp.189-198
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• 2009

Passive air samplers with polyurethane foam (PUF) disks were employed to determine seasonal gas phase variation of polycyclic aromatic hydrocarbons (PAHs) in ambient air on Anmyeon island from March 2007 to January 2008. Sum of 13 PAHs ranged between $3.5\;ng/m^3$ and $27.6\;ng/m^3$. Total PAHs during the heating season was 6.2 times higher than non-heating season. The dominant PAHs components during sampling periods were low and middle molecular weight PAHs including phenanthrene, fluoranthene, pyrene and chrysene. Gas exchange fluxes of PAHs across the air-water interface of the Yellow Sea were calculated using a modified two-film exchange model. PAHs fluxes ranged from $196\;ng/m^2/d$ net volatilization during summer to $3830\;ng/m^2/d$ net absorption during winter. Passive air sampler provides a convenient and cost-effective tool for measuring averaged gas phase PAHs, which was successfully used for calculation of gas exchange flux of PAHs in the Yellow Sea.

• 한국한의학연구원논문집
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• 제2권1호
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• pp.407-416
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• 1996

${\ulcorner}$Ilbonseogi${\lrcorner}$(edited A.D. 720) )was studied to investagate the medical and pharmaceutical exchange among ancient Korea, China and Japan. It seemed that Korean and Chinese traditional medicine was introduced to Japan through Korea. It was also shown in ${\ulcorner}$Ilbonseogi${\lrcorner}$ that Koreans who lived in china and Japan during that time seemed to hove active medical idea exchange. From various facts indicated in ${\ulcorner}$Ilbonseogi${\lrcorner}$, it was believed that Korean and Chinese traditional medicine was the basis for the foundation of Japanese traditional medicine.

• 한국재료학회지
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• 제27권3호
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• pp.161-165
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• 2017

In this paper, synthesis of terephthalate intercalated Zn-Al: Layered double hydroxides (LDHs) was studied. We designed freestanding Zn-Al: carbonate LDH nanosheets for a facile exchange technique. The as-prepared Zn-Al carbonate LDHs were converted to terephthalate intercalated Zn-Al:LDHs by ion exchange method. Initially, Al-doped ZnO (AZO) thin films were deposited on p-Si (001) by facing target sputtering. For synthesis of free standing carbonate Zn-Al:LDH, we dipped the AZO thin film in naturally carbonated water for 3 hours. Further, Zn-Al: carbonate LDH nanosheets were immersed in terepthalic acid (TA) solution. The ion exchange phenomena in the terephthalate assisted Zn-Al:LDH were confirmed using FT-IR analysis. The crystal structure of terephthalate intercalated Zn-Al:LDH was investigated by XRD pattern analysis with different mole concentrations of TA solution and reaction times. The optimal conditions for intercalation of terephthalate from carbonated Zn-Al LDH were established using 0.3 M aqueous solution of TA for 24 hours.

• 멤브레인
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• 제31권4호
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• pp.275-281
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• 2021

알칼리 수전해용 격막으로 사용가능성을 평가하기 위해 5종류의 상용 음이온교환막의 열적안정성, 이온전도도, 내구성을 평가하였다. TGA (thermo-gravimetric analysis)로 분석한 열적안정성은 FAAM-PK-75와 FAAM-40 막이 다른 3종류의 AEM, AHO, AHA 막과 비교하여 좋은 성능을 보였다. 25℃와 80℃, 7 M KOH 수용액에서의 이온전도도는 AEM막이 다른 막과 비교하여 약 4~17배 높은 값을 보였다. 25℃, 7 M KOH 수용액에서 측정한 내구성은 FAAM-PK-75막이 다른 막과 비교하여 안정하였다.

• 한국수소및신에너지학회논문집
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• 제33권4호
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• pp.330-336
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• 2022

In order to evaluate the possibility as a separator in alkaline water electrolysis, the high temperature characteristics were evaluated by measuring the membrane resistance and durability of 5 types of commercial anion exchange membranes in 7 M KOH solution and at 80℃. The membrane resistance of AEM membrane measured in 7 M KOH solution and at 80℃ had a lower value of about 8-24 times compared to the other membranes. The durability of AEM membrane tested with the soaking time in 7 M KOH solution and at 80℃ showed a very good stability and that of FAAM40 and FAAM75-PK showed secondly a good stability. The thermal stability with the soaking time in 7 M KOH solution and at 80℃ of FAAM40 and FAAM75-PK membrane analyzed by thermo-gravimetric analysis showed a good stability compared to the other membranes.

• 대한지역사회영양학회지
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• 제17권6호
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• pp.689-706
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• 2012

The purpose of this study was to evaluate effects of a nutrition education focused on Food Exchange System for the higher grades elementary children. Nutrition education lessons (40 min/lesson, 4 times), '5 major nutrients and functions', '6 food groups', 'daily needed energy and food exchange units', 'good choice of snacks and balanced exercise' were provided to elementary students (5th grade students). This research was based on the data from two groups of elementary school children in the 'education' group (n = 31) and 'non-education' group (n = 31). We assessed the changes in dietary attitude, food habit and nutrition knowledge using questionnaire and nutrient intake using 24hr recall method by nutrition education using the developed pamphlet. After education, there was a significant difference in the dietary attitude score only in attitude of 'balanced meal' (p < 0.001) in the education group compared to the non-education group. In food habit, there were significant positive changes in the type of breakfast and in the priority of choosing snack in the educated group. In nutrition knowledge, there were significant increases in scores of 'function of carbohydrate' (p < 0.05), 'function of fat' (p < 0.01), 'function of vitamin' (p < 0.01), 'foods of carbohydrate' (p < 0.01), and 'foods of vitamin' (p < 0.01) in the educated group. After education, carbohydrate: protein: fat (CPF) ratio was significantly different between the two groups (education group, 59 : 16 : 26 vs. non-education group, 63 : 15 : 23). In evaluation of nutrient intake by Dietary Reference Intakes for Koreans (KDRIs), there were significant positive effects in energy (p < 0.05), thiamin (p < 0.05), riboflavin (p < 0.05), vitamin C (p < 0.05), phosphorus (p < 0.01), Fe (p < 0.01) and zinc (p < 0.01) in the education group compared to the non-education group. In conclusion, the developed 4 times' nutritional education pamphlet focused on individual daily energy requirements and food exchange units using food exchange system for higher grades' elementary student may positively change nutrition knowledge and dietary intakes.

• 대한지역사회영양학회지
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• 제13권6호
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• pp.922-933
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• 2008

The purpose of this study was to investigate the effects of nutrition education using Food Exchange System on elementary students' nutrition knowledge, dietary attitude and nutrients intake. Nutrition education lessons (40 min /lesson, 4 times), '5 major nutrients and functions', '6 food groups and sources of 6 food groups', 'good choice of snacks and eating out' as class lesson, 'daily needed energy and food exchange units' as individual lesson, were provided to 70 elementary students (4th grade 33 students, 5th grade 37 students) in Jeonbuk Province. We assessed the changes in nutrition knowledge, dietary attitude, food habit using a questionnaire and nutrient intake using 24 hr recall method by nutrition education. In nutrition knowledge, there were significant increases in scores of 'functions of carbohydrate', 'functions of protein', 'functions of lipid', 'foods of carbohydrate', and 'foods of lipid'. In dietary attitude, there were significant increases in scores of 'taking a meal with joy', 'taking a meal at ease', 'taking a meal with sufficient protein intake' and 'taking a meal without spicy foods' by nutrition education. There were significant changes in the type of breakfast and in the frequency of snacks. After education, in type of breakfast, it showed higher number of students ate rice oriented meal than they did before education. and in frequency of snacks, it showed lower number of students ate snacks 'over 3 times' than they did before education. In Carbohydrate : Protein : Fat (CPF) ratio (%), it was significantly changed from 55.8 : 17.7 : 26.6 to 63.6 : 15.3 : 21.1. In evaluation of nutrient intake by Dietary Reference Intakes for Koreans (KDRIs), vitamin A, thiamin, niacin, vitamin $B_6$, calcium, phosphate, iron and zinc showed positive changes in distribution of number of children by intake level. That is, there were significant improvements in intakes of vitamin A, thiamin, niacin, vitamin $B_6$, calcium, phosphate, iron and zinc. These results showed that nutrition education using Food Exchange System for elementary students improved nutrition knowledge, dietary attitude and nutrients intake. It suggest that nutrition education using Food Exchange System may improve dietary behaviors and reduce an incidence of obesity in elementary students.

• 접착 및 계면
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• 제15권1호
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• pp.1-8
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• 2014

이온 교환막은 전기투석, 확산투석, Redox flow 전지, 연료전지 등 다양하고 넓은 분야에서 사용되고 있다. 초음파를 이용하여 만들어진 PVC 양이온 교환막을 시간을 변화시켜 가면서 술폰화 반응에 의해 제조하였다. 술폰화제로 황산을 사용하였으며, 술폰화 PVC 양이온 교환막의 기본구조와 특성을 FT-IR, EDX, Water uptake, 이온교환용량(IEC), 전기저항(ER), 전도도, 이온수송수 및 표면 morphology를 SEM 분석하였다. FT-IR 스펙트럼 분석결과 술폰화 PVC 양이온 교환막에 술폰산기가 도입되었음을 확인하였으며 멤브레인의 Water uptake, IEC, 전기 저항 및 ion transport number의 최대값은 각각 40.2%, 0.87 meq/g, $35.2{\Omega}{\cdot}cm^2$ 및 0.88이었다.