• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.170-170
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• 2013

형광체를 조명과 디스플레이 산업에 응용하기 위해서는 충분히 밝은 빛을 제공하는 형광체의 발광 세기가 중요한 변수이다. 이러한 발광 특성은 주로 모체 격자에 도핑 되는 활성제의 농도, 입자의 형상과 크기 분포의 균일성, 결정성에 따라 달라진다. 본 연구에서는 Ca2SiO4 모체 결정에 도핑한 활성제 Eu3+와 Dy3+ 이온의 농도를 변화시키면서 고상 반응법을 사용하여 높은 발광 효율을 갖는 Ca2-1.5xSiO4::Eux3+ 적색 형광체와 Ca2-1.5xSiO4:Dyx3+ 백색 형광체를 합성하였다. 특히, 활성제 Eu3+와 Dy3+ 이온 농도의 변화가 형광체의 결정 구조, 소성 온도, 입자의 표면 형상, 광학 스펙트럼의 발광 효율에 미치는 영향을 조사하여 최적의 합성 조건을 결정하였으며, 회절 신호의 반치폭과 발광 세기의 상호 관계를 조사하였다. Ca2-1.5xSiO4::Eux3+와 Ca2-1.5xSiO4:Dyx3+ 형광체 초기 분말 시료는 CaO (99.9% 순도), SiO2 (99.9%), Dy2O3 (99.9%)와 Eu2O3 (99.9%)인 화학 물질을 구입하여 초정밀 저울로 화학양론적으로 측정하였다. 이때 Eu와 Dy의 함량비는 x=0, 0.01, 0.05, 0.1, 0.15, 0.2 mol로 변화 시키면서 합성하였다. Ca2-1.5xSiO4: Dyx3+ 형광체 분말 시료의 경우에 소결 온도를 각각 $1000^{\circ}C$와 $1100^{\circ}C$로 달리하여 흡광과 발광 스펙트럼의 세기를 비교해 본 결과, 서로 다른 두 소결 온도에서 합성한 두 형광체 분말은 동일하게 Dy3+의 몰 비가 0.05 mol일 때 주 발광 스펙트럼의 세기는 최대값을 나타내었다. 파장 355 nm로 여기시킨 Dy3+ 함량비에 따른 Ca2-1.5xSiO4:Dyx3+ 형광체 분말의 발광 스펙트럼은 Dy3+ 함량비에 관계 없이 581 nm에서 가장 강한 황색 발광을 보였다. 함량비가 증가함에 따라 발광 스펙트럼의 변화가 관측되었는데, Dy3+의 몰 비가 0.01 mol~0.05 mol인 영역에서는 발광 세기가 증가하여 0.05 mol에서 최대를 나타내다가 Dy3+의 몰 비가 더욱 증가함에 따라 발광세기는 현저히 감소하는 경향을 나타내었는데, 이 현상은 농도 소광 현상으로 해석 할 수 있다. 이외에도, Eu3+와 Dy3+ 이온의 함량비와 소결 온도가 결정 입자의 크기와 흡광 스펙트럼에 미치는 결과를 조사하였다.

• Korean Journal of Food Science and Technology
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• v.36 no.3
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• pp.448-455
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• 2004

Changes in quality characteristics of Bijijang (fermented soybean curd residus) prepared at $35^{\circ}C\;and\;40^{\circ}C$ for 0, 12, 24, 36, and 48 hr were investigated. Acidity of Bijijang increased, whereas pH and Hunter's color values decreased during fermentation. Immediately after Bijijang preparation, ${\alpha}-and\;{\beta}-amylase$ activities were very low, ${\beta}-Amylase$ activity during fermentation increased rapidly, with those fermented at $40^{\circ}C$ higher than at $35^{\circ}C$. Neutral pretense activity was significantly higher than acidic pretense activity, and increased gradually after 12 hr. Change in total nitrogen content in Bijijang was insignificant, whereas contents of amino-type and water-soluble nitrogens increased significantly during fermentation. Major free amino acids of Bijijang were Arg, Pro, Glu, Thr, Ser, and Lys at initial fermenting stage, and, as fermentation progressed, contents of Cys, Met Glu, Ile, Leu, and Phe increased. Reducing sugar contents of Bijijang fermented at $40^{\circ}C$ were higher than those fermented at $35^{\circ}C$. Sucrose content decreased and glucose content increased. Glucoside (genistin and daidzin) contents decreased and aglycone (genistein and daidzein) contents increased during preparation of Biji and fermentation of Bijijang. Contents of free sugars and isoflavones were higher in Bijijang fermented at $40^{\circ}C$ than at $35^{\circ}C$. Based on these results, fermentation at $40^{\circ}C$ for 48 hr was determined to be optimum fermentation condition for Bijijang.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.1
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• pp.1-8
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• 1992

This study was conducted to obtain the basic information on salt-tolerance of rice cultivars in relations with growth retardation and cation content. As the salt-level increased, less retardation in plant height and dry weight were shown in salt-tolerant than salt-susceptible rice cultivars. Salt tolerant cultivars showed lower N $a^{+}$ and higher $K^{+}$ content and lower N $a^{+}$ / $K^{+}$ ratio at each salt-levels than salt-susceptible ones, while there were no significant differences in $Ca^{++}$ and $Mg^{++}$ content. At the tillering stage, the plant height and dry weight of the salt-treated plots were significantly correlated with N $a^{+}$ and $K^{+}$ content and N $a^{+}$ / $K^{+}$ ratio, implying that N $a^{+}$ and $K^{+}$ content could be an indicator of salt-tolerance of a rice cultivar. There were no tiller-depending differences in cation content in all cultivars. N $a^{+}$ content and N $a^{+}$ / $K^{+}$ ratio in leaves were lower at the top and higher at the bottom. In three $F_1$ hybrids between salt tolerant parent Pokkali and three salt susceptible parents, plant height, dry weight, $K^{+}$ content and N $a^{+}$ / $K^{+}$ ratio were similar to those of Pokkali parent, while N $a^{+}$ content was intermediate of the parents. So, it seemed that salt tolerance is dominant over salt susceptibility. In $F_2$ of Pokkali/wx817 cross, genetic segregation of plant height, dry weight, $K^{+}$ content and N $a^{+}$ / $K^{+}$ ratio varied continuously and was biased onto Pokkali side, while that of N $a^{+}$ content showed normal distribution with intermediate mode. Broad-sense heritability of the characters ranged from 0. 604 to 0. 811. Genotypic and phenotypic correlation coefficients among them were relatively high.fficients among them were relatively high.h.h.

• Korean Journal of Environment and Ecology
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• v.15 no.2
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• pp.139-152
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• 2001

충남 서부 활석광산 주변의 수계에 대한 원소 함량특성에 대해 알아보고자 대흥 및 광천광산에 대해 수질 및 하상 퇴적물 시료와 함께 광산 주변 토양 및 모암 시료를 채취, 비교하였다. 대흥지역 퇴적물은 대부분 원소에서 SP가 GN에 비해 높았는데 이는 퇴적물 내 유색 및 무색광물 함량 차이로 판단된다. 절대 함량 비교에서 광물 결정구조 내 쉽게 Mg와 치환하는 원소는 낮은비율을, Fe와 치환하는 원소는 높은 비율을 보였는데 이는 퇴적물 내 주 구성광물내 원소 치환특성을 반영하기 때문으로 판단된다. 절대 함량의 감소 순서와 타원소들과 높은 상관관계(>0.85)의 빈도를 보이는 원소들 사이의 차이는 퇴적물 화학조성에 이차광물과 비정질 광물등의 조성도 반영되었음을 암시한다. 대흥지역 지표수는 대부분 원소에서 MSP가 SP와 GN의 중간값을, MSG는 LGN과 MSP의 중간값을 조여 수계의 혼합특성을반영하는 것으로 판단된다. 절대 함량관계에서는 SP는 GW1과 유사했고, GN은 LGN과 유사했으며, 절대함량은(Mg, Fe), (As, Sc), (Mo, V, Se) 순서로 낮아졌다. 광천지역은 갱내수가 천부 지하수에 비해 대부분 원소에서 높은 함량을 보였는데, 이는 갱내수가 더욱더 많은 물-암석반응을 거친 때문으로 판단된다. 절대 함량은 Mg, Br, Fe, (Sc, Cr), (An, Ni, V)순서로 감소하였다. 갱냉수의 지역간 원소 함량 차이는 사문암화가 우세한 광천지역과 활석화가 우세한 대흥지역 모암들 사이의물-암석 상화반응의 차이를 보여주는 것으로 판단된다 두 지역의 상부 토양 및 모암 조성에서 SP가 GN에 비해 높은 Mg 비, Ni, Cr, Co 등 함량을 보였는데, 이는 사문암 지역 내 Mg, Ni, Cr 등이 풍부한 광물들 탓으로 판단된다. 퇴적물과 수질 사이에서는 함량 경향을 뚜렷하지 않았고 원소에 따라 서로 다른 힘량 차이를 보였는데, 이는 퇴적물 원소 함량이 수계 조성을 반영하는 것이 아님을 나타낸다. 상부-토양-암석-수계의 조성관계에서 대흥지역 지표수 중 SP 조성이, 광천지역은 갱냉수가 지하수의 조성에 가까웠다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.4
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• pp.614-617
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• 1994

This study was undertaken to determine the changes in amino acids, amylose and mineral contents of Jeolpyons(Korean rice cake) supplemented with various levels of roasted soybean flour (RSF). Amino acids content of Jeolpyons increased as RSF content increased. Especially the contents of total essential amino acids of Jeolpyon supplemented with RSF(5, 10, 15 and 20%) increased 1.22 to 2.74 times greater than those of the ocntrol. Amylose, which is related to retrogradatin effect on rice products decreased about 0.9 to 4.7% by increasing the soybean flour contents. Mineral contents by jeolpyon containing RSF increased as RSF contents increased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.1
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• pp.80-86
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• 1996

어류의 carotenoid에 관한 비교 생화학적 연구의 일환으로서 잉어아과에 속하는 납지리와 줄납자루의 표피와 난의 carotenoid 조성을 비교 검토하여 다음과 같은 결론을 얻었다. 납지리와 줄납자루 표피의 총 carotenoid 함량은 납지리 수컷 2.3mg%, 납지리 암컷 1.1mg%, 줄납자루 수컷 1.9mg%, 줄납자루 암컷 0.8mg%로 나타나 수컷 표피의 총 carotenoid 함량이 암컷 표피보다 다소 높았다. 표피의 carotenoid 조성은 lutein, lutein epoxide, tunaxanthin, zeaxanthin, triol 이 주성분을 이루었고 그외, $\beta-carotene,$ $\alpha-cryptoxantinm$ cyn-thiaxantin 이 함유되어 있었다. 납지리 수컷의 표피에는 줄납자루 수컷에 비해 lutein의 함량치가 높았고 줄납자루 수컷의 경우는 납지리 수컷이 비해 lutein epoxide와 tunaxanthin의 함량치가 높았다. 그리고 납지리 암컷을 표피에는 줄납자루 dkat에 비해 lutein epoxide 함량치가 높았도 줄납자루 암컷의 표피에는 납자리 와 줄납자루 난의 총 carotenoid 함량은 납지리 1.8mg%, 와 줄납자루 2.5mg%로 표피와는 달리 줄납자루 난의 함량치가 높았다. 납지리와 줄납자루 난의 carotenoid 조성은 다 같이 lutein, lutein epoxid 가 주성분을 이루었고 그외 triol은 표피에 비해 적게 함유되어 있었다. 동일한 잉어아과의 납지리와 줄납자루의 표피 및 나의 carotenoid 조성은 서로 유사함을 확인 할 수 있었다.

• The Journal of Engineering Geology
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• v.14 no.1
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• pp.105-121
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• 2004

The purpose of this study is to investigate the relationship between petrographical and engineering properties of granitic rocks, widely used as building and ornamental stones in Korea, at the Namwon are a. This area is one of the most famous area as a domestic dimension stone production. The granitic rocks were examined for grain sizes, modal compositions and then same samples were tested to determine specific gravity, water absorption, porosity, uniaxial compressive strength, tensile strength, abrasive hardness, P-wave velocity, modulus of elasticity and Poisson's ratio. It is suggested that the influence of the grain size on the engineering properties is more important than that of the mode of mineralogical compositions. And quartz contents also significantly influence the engineering properties of granitic rocks.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.4
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• pp.402-409
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• 2006

This study was performed to investigate the effects of Capsosiphon fulvescens (CF) extract on serum and liver lipid metabolism in rats. Male Sprague-Dawley rats were administered 1% cholesterol and 0.25% sodium cholate to induce hypercholesterolemia and were divided into six groups. Experimental groups were administered with following diets; normal diet group (NC), high cholesterol diet group (HC), normal diet and CF extract (200 mg/kg) administered group (NC-CFL), normal diet and CF extract (400 mg/kg) administered group (NC-CFH), high cholesterol diet and CF extract (200 mg/kg) adwlinistered group (HC-CFL), and high cholesterol diet and CF extract (400 mg/kg) administered group (HC-CFH). The body weight gain and feed efficiency ratio were increased by high cholesterol diet, but gradually decreased to the corresponding level of the normal diet group by administered CF extract. The serum total cholesterol concentration of normal diet group was significantly higher than those of NC-CFL group and NC-CFH group. The concentrations of serum total cholesterol LDL-cholesterol and triglyceride and the atherogenic index .were tended to decrease in the CF extract administered groups compared with the high cholesterol diet group. However, HDL-cholesterol and phospholipid concentrations in serum decreased in the high cholesterol diet group and markedly increased by the CF extract administered groups. There were no differences in the concentrations of serum triglyceride, phopholipid, LDL-cholesterol, HDL-cholesterol and free cholesterol in normal diet groups. Concentrations of total cholesterol and triglyceride in liver and kidney were also markedly decreased in the CF administered groups. Total cholesterol and triglyceride concentrations of adipose tissue in the CF administered groups were also decreased compared with the high cholesterol diet group. In addition, there were no differences in the concentrations of liver, kidney and adipose tissue total lipid, triglyceride and total cholesterol in normal diet groups. The activities of heparin-releasable lipoprotein lipase (LPL) and total-extractable LPL in adipose tissue were increased in the high cholesterol diet group compared with the CF extract administered groups, but those of the NC -CFL group and NC-CFH group were similar to the normal diet group. Taken together, it is suggested that the extract of CF have an antiatherosclerotic effect by reducing cholesterol level of serum and liver. Furthermore, the extract of CF decreased LPL activity and triglyceride concentration, resulting in less lipid storage.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.11a
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• pp.151-156
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• 1996

수소동위원소 교환반응에 이용되는 스티렌-디비닐벤젠 고분자 촉매 담체를 제조하였다. 중합반응시 일정한 용매계에서 용매/모노머 함량비와 팽윤제/침전제 함량비를 변화시켜 담체의 표면특성에 미치는 영향을 확인하였다. 가교도가 33%일 경우 용매/모노머가 2.0 이하에서 팽윤제/침전제의 함량비가 증가할수록 10~30$\AA$의 반경을 갖는 기공의 분포가 증가하였다. 담체의 열적안정성을 확인하기 위한 열 중량 분석에서는 온도를 일정한 비율로 단시간에 증가시킬 경우에는 담체의 가교도에 관계없이 35$0^{\circ}C$ 근처에서 거의 유사한 degradation을 보였지만 온도를 매우 천천히 증가시켜 장시간 노출시킬 경우 가교도에 따라서 degradation의 정도와 경향이 다르게 나타남을 확인하였다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.1
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• pp.53-57
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• 1993

The compositions of non-volatile organic acids, mineral, fiber and fatty acids of leaf mustard were investigated. Non-volatile organic acid contents were higher in leaf than in leaf stalk. Of non-volatile organic acids assayed malic acid was the most abundant in both leaf (79.1 mg%) and leaf stalk (46.4mg%), followed by L-ascorbic, oxalic, citric and succinic acids. Mineral contents were also higher in leaf than in leaf stalk. Both leaf and leaf stalk contained calcium most, followed by magnesium, sodium, iron, zinc and copper. It has also been found that leaf mustard contains more iron than any other Cruciferous vegetables reported. The major fatty acid of total lipid was $\alpha$-linolenir acid (63.2% in leaf, 55.3% in leaf stalk). The ratios of polyun-saturated fatty acids to saturated fatty acids (P/S ratio) were 4.1 in leaf and 2.9 in leaf stalk. The content of pectic substances, in terms of alcohol-insoluble solid, of leaf was 9.4% which was 1.4-fold higher than that of leaf stalk. Of pectic substances, hot soluble pectins (HWSP) were present most and followed by sodium hexametaphosphate soluble (HXSP) and HCI soluble pectins (HSP). Total dietary fiber content of mustard leaf was 2.68% and in general, higher content of total dietary fiber than leaf had. Neutral detergent fiber content was higher than acid detergent fiber, and cellulose was higher than hemicellulose by 2.1-fold in leaf stalk.