• 제목/요약/키워드: Ca-source

검색결과 751건 처리시간 0.021초

고체산화물연료전지 연결재용 La0.7Ca0.3Cr0.9Co0.1O3-δ 조성계에 Ca Source 변화에 따른 소결 및 전기적 특성에 관한 연구 (Effects of Ca-Source on the Sintering and Electrical Properties of La0.7Ca0.3Cr0.9Co0.1O3-δ for Solid Oxide Fuel Cell Interconnects)

  • 박성태;최병현;지미정;안용태;최헌진
    • 한국세라믹학회지
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    • 제48권3호
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    • pp.246-250
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    • 2011
  • Effects on sintering and electrical properties of $La_{0.7}Ca_{0.3}Cr_{0.9}Co_{0.1}O_{3-{\delta}}$ system, a interconnect material for cylindrical and flat tubular solid oxide fuel cells (SOFC), have been investigated by Ca-source when using $CaCO_3$ and $CaF_2$. When using $CaCO_3$ and $CaF_2$ was mixing as Ca-source, single phased perovskite solid solution was observed for each sample. The sintering temperature was decreased by $CaF_2$ contents was increased. When using 0.1 mole $CaF_2$ was densely sintered at $1400^{\circ}C$ and relative density was 93.8%. Also, electrical conductivity in oxidation and reducing atmosphere was 47, 4.3 S/cm, respectively, due to $F^-$ ion enhance the electrical conductivity in reducing atmosphere.

칼슘급원으로서의 불가사리 칼슘의 체내이용성 (Bioavailability of Starfish Calcium as a Novel Calcium Source)

  • 이연숙;문지영;장수정
    • 한국지역사회생활과학회지
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    • 제16권1호
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    • pp.135-148
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    • 2005
  • This study was conducted to investigate the bioavailability of calcium derived from starfish as a new calcium source. Four-week old Sprague-Dawley female rats were divided 6 groups. The rats were received experimental diets containing two kinds of Ca sources, CaCO₃ or starfish, and three levels of Ca, low (0.1 %), medium (0.5%) and high (1.0%), respectively, for 6 weeks. The parameters which related to Ca bioavailability were measured : Serum Ca concentration, Alkaline phosphatase(ALP) and GOT activities ; tissue Ca contents, bone dimension and Ca, P, Mg contents; Ca retention and apparent absorption. Starfish Ca-fed rats did not show any difference from CaCO₃-fed rats in terms of growth, food intake and FER. Serum Ca, ALP and GOT activities as well as tissue Ca contents were not different between CaCO₃- and starfish Ca-fed groups. Although dimension of femur and lumbar was not different between CaCO₃- and starfish Ca-fed rats, ash content was high in starfish Ca-fed rats. Ca and P contents of femur and lumbar were not different between both groups. Starfish Ca-fed groups showed higher Mg contents than CaCO₃-fed groups in both femur and lumbar. Ca absorption rate and retention rate were significantly higher in starfish Ca-fed rats. These results indicate that Ca derived starfish did not show any negative effect on growth and Ca metabolism of rats compared to calcium carbonate. Starfish Ca can be recommended as a good Ca source on the basis of higher Ca absorption and bioavailability.

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Submicron 부유분진의 화학적 조성 및 분포에 관한 연구 (Studies on the Chemical Compositions and Distributions of Ambient Sumicron Aerosols)

  • 황인조;김동술
    • 한국대기환경학회지
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    • 제14권1호
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    • pp.11-23
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    • 1998
  • The purpose of this study was to survey chemical distribution of inorganic elements and ions in the submicron particles, to characterize qualitatively emitting sources by factor analysis, and finally to reveal existing patterns in terms of chemical compounds by a stepwise multiple regression analysis. Total of 141 samples were collected by a cascade impactor from 1989 to1996. Fifteen chemical species (Al, Ba, Cd, K, Pb, Cu, Fe, Ni, $Cl^-, NO_3^-, SO_4^{2-}, K^+, Mg^{2+}, Ca^{2+}, and Na^+$) were characterized by AAS and IC. The study showed that average seasonal levels of submicron particulate matters $(d_p<0.43 \mum)$ were 18.7 $\mug/m^3$ in spring, 15.5 $\mug/m^3$ in summer, 15.7 $\mug/m^3$ in fall, and 24.5 $\mug/m^3$ in winter, respectively. All of the anion concentrations in the particle were highest in the winter season. By applying a factor analysis, 5 source patterns were qualitatively obtained, such as sulfate related source, nitrate related source, oil burning source, calcium related source, and coal combustion source. Finally, when applying a stepwise multiple regression analysis, the results clearly showed that $Na^+ and Ca^{2+}, K^+ and Ca^{2+}, NO_3^-$ and relative humidity, $Cl^-$ and ambient temperature, $Ca^{2+} and Cl^-, Mg^{2+} and SO_4^{2-}, Na^+ and NO_3^-, and Ca^{2+} and NO_3^-$, respectively, are negatively contributed to each other. As a result of those statistical analysis, we could suggest that some chemical compounds in the submicron particles such as$NaNO_3, MgSO_4, Ca(NO_3)_2, and CaCl_2$ may not exist on the filter as final composing products; however, other compounds may possibly exist in the form of $Mg(NO_3)_2, CaSO_4, Na_2SO_4, K_2SO_4, MgCl_2, NaCl, and KCl$. Thus, it must be necessary to identify differences between the results of above statistical analysis and of the real world by laboratory experiments.

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Tilapia Mossambica 비늘 (어린) 유래 칼슘소재가 흰쥐의 골격대사지표와 골밀도에 미치는 영향 (Effect of Calcium Source using Tilapia Mossambica Scales on the Bone Metabolic Biomarkers and Bone Mineral Density in Rats)

  • 윤군애;김광현
    • Journal of Nutrition and Health
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    • 제43권4호
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    • pp.351-356
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    • 2010
  • 본 연구는 칼슘고갈식이와 칼슘회복식이를 급여한 SD 종 흰쥐에서 골격대사 지표와 골밀도를 측정함으로써 어린소재 Ca (Tilapia mossambica 비늘을 이용한 칼슘소재)의 유용성을 $CaCO_3$와 비교 평가하였다. 1) 칼슘고갈식이인 LoCa군에 비해 칼슘회복식이를 먹인 AdCa군과 AdFa군에서 체중증가, 사료섭취량이 유의하게 높았고, 이는 어린소재 Ca의 식이효율이 적정수준에 있다고 할 수 있다. 2) 혈청 PTH와 칼시토닌은 실험군 사이에 차이가 없었다. 3) 혈청 ALP와 오스테오칼신은 LoCa군에서 유의하게 증가하였고, AdCa와 AdFa군에서 저하되었다. 뇨의 DPD는 LoCa군에서 현저히 높은 수치를 보인 반면, AdCa와 Ad-Fa군에서 낮은 수치를 보임으로써 뼈의 형성지표와 흡수지표는 칼슘회복식이에 의해 개선되었다. 4) 대퇴골의 습윤무게, 건조무게, 체중 100g 단위당 중량이 모두 AdFa > AdCa > LoCa 순으로 높았고, 대퇴골의 회분함량과 칼슘함량도 모두 같은 순서를 보임으로써 뼈의 형성과 칼슘 축적에 AdCa군과 마찬가지로 AdFa군에서도 효과적이었음을 시사한다. 5) 대퇴골의 골밀도는 AdCa군과 AdFa군에서 LoCa군에 비해 25~26%의 유의하게 높은 수치를 보였다. 이상에서와 같이 칼슘회복식이 (AdCA와 AdFa)는 ALP, 오스테오칼신, DPD의 지표를 개선하였고, 대퇴골의 중량과 회분함량의 증가와 함께 골밀도를 향상시키는 것으로 나타났다. 따라서 어린소재 칼슘은 대조 칼슘급원으로 많이 사용되는 $CaCO_3$에 비교하여 뼈 건강에 대등한 효과를 보이므로, 칼슘 소재로서 개발될 가치가 있을 것으로 평가된다.

난각 칼슘의 생체 이용성에 관한 연구 (A Study on the Calcium Bioavailability of Eggshell Powder in the Growing Rats)

  • 장순옥
    • Journal of Nutrition and Health
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    • 제36권7호
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    • pp.684-690
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    • 2003
  • This study has investigated the bioavailability of calcium in eggshell powder (ESP) for the purpose of reutilizing eggshells as the calcium source. The experiment was designed 2 ${\times}$ 2 factorial method with two sources, CaCO$_3$ and ESP, and two levels, 0.2% and 0.4% calcium. Weanling SD rats were assigned randomly to one of 4 groups and provided by one of the isocaloric, 20% casein based 4 different experimental diets for 4weeks. Deionized water was given and environment was kept from any contamination of minerals. The body weight, diet intake, feed efficiency ratio (FER), bone growth, Ca contents of bones, and apparent absorption were measured. FER (0.38 - 0.40) and kidney weight were not different among groups and the weight and length, Ca content, strength of two bones Tibia and Femur were not affected by Ca sources except Femur Ca content. Ca content of Femur was greater in ESP groups than that of CaCO$_3$ groups. The body weight gain, bone growth, the Ca contents and strength of bones were significantly greater in 0.4% calcium groups suggesting 0.2% calcium is not sufficient for the optimum growth in the growing rats. These results indicate that ESP be a proper Ca source comparable or superior to CaCO$_3$. However the apparent absorption rate of final 3 days of feeding did not support the observed results showing lower rate in ESP than CaCO$_3$ groups. Further study be needed in the absorption aspect.

Ca 추출 슬래그를 실리카 원료로 사용한 압출성형시멘트 패널의 특성 (Properties of Extruding Cement Panel Using Ca-extracted Slag as Silicious Source)

  • 최홍범;김진만;유재성;현지수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2016년도 추계 학술논문 발표대회
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    • pp.117-118
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    • 2016
  • This paper evalutes properties of extruding cement panel using Ca-extracted convert slag and air-cooled blast furnace slag. Flexural strength of extruding cement panel has measured in air dry and autoclave curing as basic study for use as silicious source. As a result, when Ca-extracted converter slag replaces 25% in autoclave curing, flexural strength measures 13.1MPa better than panel control mix. In result of using air-cooled blast furnace slag, Ca-extracted air-cooled blast furnace slag dose not show increase of flexural strength.

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강하분진의 화학적 특성파악을 위한 통계학적 해석 (Statistical Analysis for Chemical Characterization of Fall-Out Particles)

  • 김현섭;허정숙;김동술
    • 한국대기환경학회지
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    • 제14권6호
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    • pp.631-642
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    • 1998
  • Fall-out particles were collected by the modified British deposit gauges at 35 sampling sites in Suwon area from January to November, 1996. Twenty chemical species (Al. Ba, Cd, Cr, K, Pb, Sb, Zn, Cu, Fe, Ni, V, F-, Cl-, NO3-, 5042-, Na+, NH4+, Mg2+, and Ca2+) were analyzed by AAS and If. The purposes of this study were to estimate qualitatively various emission sources of the fell-out particle by applying multivariate statistical techniques such as factor analysis, multiple regression analysis, and discriminant analysis. During the study, outlier sites were determined by a z-score method. Cl-, Na+, Mg2+, and SO42- were highly correlated due to their common marine related source. Wind speed was the most influential factor for the deposition fluxes of the particle itself and all the chemical species as well. When applying the factor analysis, 8 source patterns were qualitatively obtained, such as marine source, soil source, oil burning source, Cr related source, tire source, Cd related source, agriculture source, and F- related source. As a result of the multiple regression analysis, we could suggest that some chemical compounds may possibly exist in the form of CaSO4, NaN03, NaCl, MgC12, (NH4)2SO4, NaF, and CaCl2 in the fall-out particles. Finally, spatial and seasonal classification study performed by a discriminant analysis showed th.at SO42-, Ca2+, Cl-, and Fe were dominant in the group of spatial pattern; however, SO42-, Cl-, Al, and V were in the group of seasonal pattern.

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Characterization of physiochemical and nutrient profiles in canola feedstocks and co-products from bio-oil processing: impacted by source origin

  • Alessandra M. R. C. B. de Oliveira;Peiqiang Yu
    • Animal Bioscience
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    • 제36권7호
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    • pp.1044-1058
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    • 2023
  • Objective: The objective of this study was to characterize physiochemical and nutrient profiles of feedstock and co-products from canola bio-oil processing that were impacted by source origin. The feedstocks and co-products (mash, pellet) were randomly collected from five different bio-oil processing plants with five different batches of samples in each bio-processing plant in Canada (CA) and China (CH). Methods: The detailed chemical composition, energy profile, total digestible nutrient (TDN), protein and carbohydrate subfractions, and their degradation and digestion (CNCPS6.5) were determined. Results: The results showed that TDN1x was similar in meals between CA and CH. CH meals and feedstock had higher, truly digestible crude protein (tdCP) and neutral detergent fiber (tdNDF) than CA while CA had higher truly digestible non-fiber carbohydrate (tdNFC). The metabolizable energy (ME3x), net energy (NELp3x, NEm3x, and NEg3x) were similar in meals between CA and CH. No differences were observed in energy profile of seeds between CA and CH. The protein and carbohydrate subfractions of seeds within CH were similar. The results also showed that pelleting of meals affected protein sub-fractionation of CA meals, except rapidly degradable fractions (PB1), rumen degradable (RDPB1) and undegrdable PB1 (RUPB1), and intestinal digestible PB1 (DIGPB1). Canola meals were different in the soluble (PA2) and slowly degradable fractions (PB2) between CA and CH. The carbohydrate fractions of intermediately degradable fraction (CB2), slowly degradable fraction (CB3), and undegradable fraction (CC) were different among CH meals. CH presented higher soluble carbohydrate (CA4) and lower CB2, and CC than CA meals. Conclusion: The results indicated that although the seeds were similar within and between CA and CH, either oil-extraction process or meal pelleting seemed to have generated significantly different aspects in physiochemical and nutrient profiles in the meals. Nutritionists and producers need to regularly check nutritional value of meal mash and pellets for precision feeding.

스톡스 유동장 내의 한 쌍의 소오스-싱크에 의한 자유표면 유동해석 (Analysis on the free surface flow induced by a pair of source-sink in Stokes flow)

  • 정재택;박종선
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2008년도 춘계학술대회논문집
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    • pp.304-307
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    • 2008
  • Two-dimensional Stokes flow due to the line source and line sink of same strength in semi-infinite flow region with free surface is analysed using complex variable theory and conformal mapping. Surface tension effects are included while gravity is neglected. From the results of analysis, flow pattern and free surface shape are obtained and velocity distribution on the free surface is determined with 2 independent parameters Ca (capillary number) and h (non-dimensionalized distance between source and sink). When the location of the sink is above the source, velocity on the free surface converges and a cusp occurs on the free surface for the value of Ca above some critical capillary number.

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고지의 효과적인 활용을 위한 in-situ 탄산칼슘 부착방식의 연구 (1) - 탄산칼슘의 부착 효과 증대를 위한 고분자 전처리 - (Application of In-situ CaCO3 Formation Method for Better Utilization of Recycled Fibers (1) - Enhancing Attachment of CaCO3 to Fibers by Polymer Pre-Treatment -)

  • 서영범;이민우;이영호;정재권
    • 펄프종이기술
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    • 제46권5호
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    • pp.19-26
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    • 2014
  • In-situ $CaCO_3$ formation on recycled wood pulp was studied to improve optical property and filler attachment to the fiber furnish in papermaking. We tried to attach calcium oxide (CaO) to the recycled fibers, old newspaper (ONP) in this case, by using selected polymers before in-situ $CaCO_3$ formation reaction on fibers, and then, $CO_2$ was injected to the furnish until all the CaO on fiber surfaces was consumed. It was found that the attachment of newly formed $CaCO_3$ to recycled fibers became stronger by attaching CaO to the fibers before in-situ $CaCO_3$ formation reaction. It was expected that the polymers used for the attachment of calcium source to the fiber furnishes helped to keep the newly formed $CaCO_3$ strongly attached to the fiber surface as well as to retain the impurities associated with calcium source and recycled fibers, if any. In-situ $CaCO_3$ formation gave higher brightness and much less ERIC value in ONP sheet than the case when the equivalent amount of GCC was added to the furnish.