• Journal of Nutrition and Health
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• 제44권6호
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• pp.474-480
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• 2011

Calcium (Ca) is an essential element to maintain body homeostasis. However, many factors disturb calcium absorption. Aspartic acid chelated calcium (AAC) was synthesized by new methods using calcium carbonate and aspartic acid. This study was carried out to investigate the bioavailability of AAC in Ca-deficient rats. The experimental groups were as follows: NC; normal diet control group, CD-C; untreated control group of Ca-deficient (CD) rats, CD-$CaCO_3$; $CaCO_3$ treated group of CD rats, CD-AAC; AAC treated group of CD rats, and CD-SWC; and seaweed-derived Ca treated group of CD rats. The Ca content of various types of Ca was held constant at 32 mg/day, and the four CD groups were fed for 7 days after randomized grouping. Ca content in serum, urine, and feces within feeding periods were analyzed to confirm Ca absorption. Serum Ca content was significantly higher in the CD-AAC (11.24 mg/dL) and CD-SWC (10.12 mg/dL) groups than that in the CD-C (8.6 mg/dL) group 2 hours following the first administration. The Ca content in feces was significantly lower in the CD-AAC (35.4 mg/3 days) and CD-SWC (71.1 mg/3 day) groups than that in the CD-$CaCO_3$ (98.7 mg/3 days) group (p > 0.05). AAC had a 2.3-fold higher absorption rate of Ca than that of SWC. No differences in fibula length were observed in the NC and CD groups. The fibula weights of the CD-AAC (0.33 g) and CD-SWC (0.33 g) groups increased compared to those in the CD-C (0.27 g) group; however, no significant difference was observed between the CD groups. We conclude that bioavailability of AAC is higher than that of seaweed-derived Ca or inorganic Ca. Thus, these findings suggest the AAC has potential as a functional food material related to Ca metabolism.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2001년도 추계학술대회 및 정기총회
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• pp.109-109
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• 2001

The present study was done to investigate the relationship between Kupffer cells and alteration of cytochrome P-450 (CYP)-dependent drug metabolizing enzyme activities during polymicrobial sepsis. Male rats were subjected to polymicrobial sepsis by cecal ligation and puncture (CLP) followed by fluid resuscitation. The gadolinium chloride (GdC1$_3$, 10 mg/kg), blocker of Kupffer cells, was pretreated intravenously at 48 h and 24 h prior to the induction of CLP. All assay parameters were determined at 24 h after CLP or sham operation. In CLP-treated rats, the mortality rate of animals increased to 50% and serum alanine (ALT) and aspartate aminotransferase (AST) levels also significantly elevated. However, this increase was not suppressed by GdC1$_3$ pretreatment. Microsomal lipid peroxidation markedly increased after CLP operation. This increase was significantly attenuated by pretreatment. Total cytochrome P-450 content and NADPH-cytochrome P-450 reductase activity were not changed after CLP operation, but GdC1$_3$pretreatment reduced total cytochrome P-450 content, The hepatic microsomal CYP 1A1, 1A2, 2Bl and 2El activities in CLP-induced rats were also not significantly different from sham-operated rats. However, GdC1$_3$pretreatment showed a moderate increase in CYP1A1 and 1A2 activities. Our findings suggest that Kupffer cells may be partly responsible for producing hepatocellular dysfunction during sepsis.

• 공업화학
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• 제19권4호
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• pp.421-426
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• 2008

본 연구에서는 다양한 조성의 다중벽 탄소 나노튜브/폴리스티렌 복합체들을 유화제를 이용한 용액공정을 이용하여 제조하였다. 이때, 분자량이 다른 3종의 폴리스티렌(PS-1 : ${\bar{M}}_n$ = 101500 g/mole, PS-2 : ${\bar{M}}_n$ = 89900 g/mole, PS-3 : ${\bar{M}}_n$ = 85000 g/mole)을 사용하였다. 복합체에서 매트릭스로 사용된 폴리스티렌의 임계흐름온도($T_{cf}{\sim}195^{\circ}C$) 이상과 이하인 $210^{\circ}C$ 및 $180^{\circ}C$에서의 열적 거동을 동적 유변측정기를 이용하여 측정하였다. 복합체의 저장 탄성율, 손실탄성율 및 용융점도는 복합체내에서 다중벽 탄소 나노튜브 함량이 증가함에 따라 증가하였으며, 용융점도의 경우에는 다중벽 탄소 나노튜브 함량이 2 wt%에서 5 wt% 사이에서 가장 큰 증가가 관찰되었다. $210^{\circ}C$의 유변특성 거동에 의하면, 특정 다중벽 탄소 나노튜브 함량에서 복합체의 점성 특성이 탄성특성으로 전이되는 현상이 관찰되었으며, 이때 다중벽 탄소 나노튜브 함량은 MWCNT/PS-1, MWCNT/PS-2 및 MWCNT/PS-3 조성에 대해 각각 3.5 wt%, 3.2 wt 및 3.0 wt%를 나타내었다.

• International Journal of Contents
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• 제6권3호
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• pp.10-14
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• 2010

Researchers in Korea and elsewhere have carried out a wide variety of important research activities in their respective fields, producing valuable research results. For such diverse research results to be shared and exchanged among researchers working in the same discipline and research subject there needs to be a community environment based on free utilization of information. Against this backdrop, this study seeks to classify and reprocess the reference/factual content owned by the KISTI (Korea Institute of Science and Technology Information), a state-run distributor of information on science and technology, by the different research subjects. It also seeks to develop and provide a community model based on the concepts of open archiving and open access for the researchers specialized in the related fields of research. This community model is developed focusing on the research results from the field of bioscience, where the most extensive studies are currently being conducted. To develop the community model, this study: (a) surveys the current status of the content owned by KISTI; (b) analyzes the patterns and characteristics of biological scientific content among the KISTI-owned content; and (c) designs a web platform where researchers can freely upload/download research results.

• 대한금속재료학회지
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• 제49권2호
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• pp.153-160
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• 2011

The AISI 216L stainless steel with a composition of Fe-16Cr-6Ni-6Mn-1.7Mo (wt.%) was oxidized at $700{\sim}900^{\circ}C$ in air for 100 h. At $700^{\circ}C$, a thin $Mn_{1.5}Cr_{1.5}O_4$ oxide layer with a thickness of $0.4{\mu}m$ formed. At $800^{\circ}C$, an outer thin $Fe_2O_3$ oxide layer and a thick inner $FeCr_2O_4$ oxide layer with a total thickness of $30{\mu}m$ formed. The non-adherent scale formed at $800^{\circ}C$ was susceptible to cracking. At $900^{\circ}C$, an outer thin $Fe_2O_3$ oxide layer and a thick inner $Mn_{1.5}Cr_{1.5}O_4$ oxide layer formed, whose total thickness was $10{\sim}15{\mu}m$. The scales formed at $900^{\circ}C$ were non-adherent and susceptible to cracking. 216 L stainless steel oxidized faster than 316 L stainless steel, owing to the increment of the Mn content and the decrement of Ni content.

• 한국토양비료학회지
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• 제29권4호
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• pp.378-384
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• 1996

우리 나라 기후조건에서 생육기의 근권온도가 사과나무 후지/M26 1년생의 생육(生育), 양분흡수(養分吸收) 및 뿌리의 발달에 미치는 영향을 시험한 결과는 다음과 같다. 1. 근권온도(根圈溫度) 처리(處理)에 의한 신초길이는 $20^{\circ}C$에서 7.9~15.8cm, $35^{\circ}C$에서 13.4~28.9cm로 근권온도가 높을수록 많았고 간주비대량(幹周肥大量)과 뿌리 생장량은 $35^{\circ}C$에서 가장 많았고 뿌리의 수분함량도 $35^{\circ}C$로 온도가 높을수록 많은 경향이다. 2. 엽록소함량은 온도처리간에 차이가 적었으며 엽수분(葉水分)포텐셜은 $35^{\circ}C$에서 처리 15일에 $35^{\circ}C$에서 -1.15~1.81 MPa고 높았으나 60일에는 -1.82~-2.10 MPa로 낮아 잎에 수분함량이 적었다. 3. 엽중(葉中) 무기성분함량(無機成分含量) 중(中) '93년에 질소, 칼슘 및 마그네슘은 차이가 없었으나 인산은 $30^{\circ}C$에서 가장 많았고, 칼리는 $30^{\circ}C$부터 함량이 낮아졌다. '94년에 질소는 차이가 없으나 인산과 칼리는 $25^{\circ}C$ 처리구에서 가장 많았고, 칼슘은 $30{\sim}35^{\circ}C$에서 처리기간이 길어짐에 따라 현저히 증가하였으나 마그네슘은 $20{\sim}25^{\circ}C$에서 처리기간이 길어짐에 따라 현저히 감소하였다. 4. 뿌리의 무기성분함량(無機成分含量)은 '93년과 '94년 공히 질소와 칼리는 온도가 높아짐에 따라 증가하였고 인간과 마그네슘은 $35^{\circ}C$에서 '94년은 많았으나 칼슘은 차이가 없었다. 따라서 3개월간의 근권온도(根圈溫度) 처리(處理)는 $30{\sim}35^{\circ}C$에서 수체(樹體) 및 뿌리의 생육(生育)이 촉진되며 $25{\sim}30^{\circ}C$에서 엽중 무기성분함량(無機成分含量)이 가장 높아 우리나라의 기후에서 일시적으로 지온이 $30^{\circ}C$정도 되어도 Fuji/M26 사과 품종(品種)은 재배(栽培)에 문제가 없는 것으로 생각되었고, 영양진단(營養診斷)에 의한 시비관리(施肥管理)를 하는 경우 엽중(葉中) 무기성분함량(無機成分含量)은 물론 근권(根圈)의 온도(溫度)와 기상조건(氣象條件)을 함께 고려함이 바람직하다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권8호
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• pp.570-576
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• 1999

$LaCrO_3$-dispersed Cr alloys for metallic interconnector of solid oxide fuel cell have been studied as function of $LaCrO_3$ content in the range of 5 to 25 vol.% in order to examine the electric conductivity, the oxidation property and the thermal expansion behavior of these alloys. The $LaCrO_3$-dispersed Cr alloys showed high electrical conductivities of $3~5\times10^4$ S/cm at room temperature, and as the $LaCrO_3$content increased the conductivity decreased slightly. During the cyclic oxidation test at $1100^{\circ}C$, the weight change of the Cr alloys decreased with increasing number of oxidation cycle except first cycle, which is attributed to the vaporization of the oxide scale. More addition of the $LaCrO_3$ content reduced also the weight change of the Cr alloys. These mean that the oxide scale formed at the surface of the Cr alloy becomes stable with increasing number of oxidation cycle and$LaCrO_3$ content. The measured thermal expansion of the Cr alloy was well fitted to that of 8 mol% $Y_2O_3$-stabilized $ZrO_2$ electrolyte. These results demonstrate that $LaCrO_3$-dispersed Cr alloy is a useful material for metallic interconnector of solid oxide fuel cell.

• 한국세라믹학회지
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• 제29권7호
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• pp.577-585
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• 1992

TiB2 and TiC were prepared from the mixture of metal titanium, boron and graphite powders in Argon atmosphere by Self-propagating High-temperature Synthesis method. The sintered properties of TiB2-TiC composite as a function of TiC content and sintering temperature were investigated in TiB2 matrix. The sintered properties were the most excellent at 10 wt% TiC content in TiB2-TiC composite. The relative density, M.O.R strength, hardness and fracture toughness of TiB2-10 wt% TiC composite sintered at 190$0^{\circ}C$ for 90 min by hot-pressing under the pressure of 30 MPa were 98.6%, 634 MPa, 2128.1 kg/$\textrm{mm}^2$ and 4.09 MN/m3/2, respectively.

• 한국식품과학회지
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• 제47권2호
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• pp.158-163
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• 2015

참옻나무의 줄기전체, 껍질, 목질부위에 함유되어있는 총 phenol 함량은 원주산이 각각 15.73, 13.29, 13.21, 옥천산이 16.14, 16.63, 14.81 mg gallic acid/g db이었다. 총 flavonoid 함량은 원주산이 32.04, 15.16, 31.05, 옥천산이 45.51, 22.09, 43.48 mg quercetin/g db로 나타났다. Flavonoid 성분 중 fustin이 껍질 부위에서는 성분합계양의 98%이상, 줄기와 목질에서는 73.0-86.7%를 차지하는 주요성분이었다. Butein은 부위별로 0.31-2.17, fisetin은 0.27-3.32, sulfuretin은 0.15-0.80 mg/g db 함유되어 있었다. 각 부위별 urushiol 함량의 합계는 각각 5.09-6.29, 55.05-56.30, 0.38-0.39 mg/100 g dry base로 껍질에 다량함유 되어 있었다. 껍질에 함유된 urushiol congener들의 분포는 C15:3 (pentadecatrienyl catechol)이 63%, C15:1 (pentadecenyl catechol)이 33-35%, C15:2 (pentadecadienyl catechol)가 2-3% 함유되어 있었다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.648-649
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• 2006

The dry-milling technique was used for mixing and crushing oxides and graphite powders. The ratio of ball-to-powder was 30:1 and argon gas was filled in jar. The excess carbon was $10{\sim}20wt%$ of the stoichiometric amount. The dry-milling was carried for 20 hours. The mixed powders were reduced and carburized at $900{\sim}980^{\circ}C$ for 3 hours flowing Ar gas in tube furnace. The dry-milled powders showed the wide diffraction patterns of X-ray. The reactions of reduction and carburization were completed in 3 hours at $980^{\circ}C$. After the reactions, the mean size of WC particles was about 200 nm. The content of free carbon in WC/Co mixed powders was less as the reaction temperature increased.