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        61.
        2017.05 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        As a basic study for the removal of oxygen in solid Nd metal by metal Ca vapour, by using the thermodynamic data such as ΔG-T diagrams and Nd-O and Nd-Ca equilibrium diagrams, the amount of residual oxygen in solid Nd metal formed based on deoxidation reaction by Ca vapour, instead of by direct contact of solid Nd metal and Ca solution, was determined. Deoxidation experiments were carried out for solid Nd metal in a temperature range of 890~970 ℃ for 1h to 4h and content of addition Ca of 0.6~1.8 g (5~15 wt% of solid Nd metal). As a result, it was found that as deoxidation temperature increased, dissolved oxygen decreased. Especially, it was observed that a small amount of Nd-Ca alloy liquid was formed on the surface of the solid Nd metal sample deoxidized at 970 ℃ for approximately 1 hour. Also, it was found that if the content of addition Ca was 1.8 g (15 wt% of solid Nd metal) the amount of produced Nd-Ca alloy increased slightly. However, for the Nd sample with which the deoxidation reaction was performed at 930 ℃ for 4h with content of addition of Ca of 1.5 g (13 wt% of Nd metal), the residual oxygen was found to decreased to 12.00 ppm.
        4,000원
        62.
        2017.04 구독 인증기관·개인회원 무료
        Phospholipase A2 (PLA2) hydrolyzes phospholipids at sn-2 position to release free fatty acids. PLA2 consists of a superfamily mainly categorized as secretory PLA2 (sPLA2), cellular Ca 2+ -dependent PLA2 (cPLA2), and cellular Ca 2+ -independent PLA2 (iPLA2). We are the first to report iPLA2 in insect. Here an objective of our study is to purify a recombinant iPLA2 protein (SeiPLA2) of Spodoptera exigua using bacterial expression system. An open reading frame of SeiPLA2 was cloned into an expression vector and then transformed into Escherichia coli BL21. Over-expression with IPTG yielded recombinant SeiPLA2 (rSeiPLA2), which was then purified by an affinity chromatography using Ni-NTA column. The purified rSeiPLA2 gave significant PLA2 activity using a pyrene substrate. Its activity was inhibited by an iPLA2 specific inhibitor (BEL), but not by sPLA2 inhibitor (BPB) or cPLA2 inhibitor (MAFP
        63.
        2017.04 구독 인증기관·개인회원 무료
        Reactive oxygen species (ROS) induces oxidation against various biomolecules including fatty acids. Calcium-independent cellular phospholipase A2 (iPLA2) has been known to function maintenance of fatty acids in phospholipids in mammals. An insect iPLA2 (Pi-iPLA2) was predicted from transciptomes of the Indianmeal moth, Plodia interpunctella. It was expressed in all developmental stages from egg to adult. RNA interference (RNAi) against Pi-iPLA2 was performed with specific double-stranded RNA (dsRNA) with more than 70% efficiency in reduction of its expression. Under this RNAi condition, P. interpuctella exhibited developmental retardation with significant accumulation of lipid peroxidation measured by the amount of melondialdehyde
        64.
        2016.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 응집제로 calcium alginate를 이용한 질산성 질소 처리에 관한 연구이다. 질산성 질소를 제거하기 위한 방법으로는 역삼투법, 이온교환수지법, 전기투석법, 생물학적 방법 등이 있지만 본 연구에서는 응집 침전시키는 방법으로서 질산성 질소를 처리하고자 하였다. 응집제로 이용한 calcium alginate가 킬레이트 결합을 형성하여 질산성 질소를 응집 침전시킬 것으로 예상하고, 응집제의 성분, 응집 반응시간, 응집제의 몰비, 응집제의 주입율에 따라 질산성 질소가 제거되는 경향을 보았다. 또한 FE-SEM과 EDS(Energy Dispersive X-Ray Spectrometer)를 통하여 응집반응 후 침전물의 구조 및 구성성분비를 분석함으로써 질산성 질소가 Calcium-nitro-alginate 형태로 제거되는지를 확인하였다. 그 결과 반응시간은 60분, 응집제의 몰비는 1:1일 때, 응집제의 주입율은 합성폐수의 2 %일 때 질산성 질소의 제거율이 최대 56.7 %로 나타났다.
        4,000원
        65.
        2016.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study was to investigate the effects of ionized calcium treatment on total bacterial cross-contamination of chicken carcass surface in the slaughtering process. The growth of Escherichia coli was strongly inhibited in a medium prepared by using a 0.5% ionized calcium solution. The total bacterial cross-contamination of chicken carcass surface and the scalding water was significantly increased as the number of scalding was increased (p<0.05). The total bacterial cross-contamination of chicken carcass surface reached a plateau without a further increase as scalding was performed consecutively for 10 or more times. The total bacterial cross-contamination of the scalding water was significantly increased as the number of scalding was increased (p<0.05). The total bacterial cross-contamination of chicken carcass surface of the chickens raised on a floor type farm was significantly higher than that of the chickens raised in a battery cages (p<0.05). The total bacterial cross-contamination of chicken carcass surface of the chickens raised on a floor type farm was significantly lower in the 0.5% ionized calcium solution treatment group than in the control group (p<0.05).
        4,200원
        66.
        2016.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The investigation of effects on fouling propensity with various viscosity of feed solutions would be better understanding for forward osmosis (FO) performance since the fouling propensity was directly influenced with solution viscosity. Therefore, this study was focused on the FO fouling with model foultants (humic acid, alginate) by altering solution viscosity with change of ionic strength (I.S) and Ca2+ concentrations. In the comparison between humic acid and alginate, as expected, the alginate generally caused more severe fouling (almost 35.8 % of flux reduction) based on the solution characteristics (high viscosity) and fouling patterns (coil and gel layer). However, interesting point to note is that the fouling propensity of alginate was more severe even though it was applied with low viscosity of feed conditions (I.S = 20 mM, Ca2+ = 1 mM). This might be due to that crossed linked gel layer of alginate on the FO membrane surface could be best formed in the condition of Ca2+ presence and higher I.S, and that is more dominant to fouling propensity than the low viscosity of feed solutions.
        4,000원
        67.
        2016.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 칼슘과 철 그리고 철과 아연의 상호작용과 신뢰성있는 영양정보를 제공하기 위해 영양강조표시제품중 칼슘, 철, 아연의 함량을 분석하고 표시량과 분석값을 비교하였다. 칼슘, 철, 아연을 강조표시한 제품(시리얼, 과자, 두유, 초콜릿가공품, 기타코코아가공품, 당류가공품, 과줆채음료, 고형차) 총 42건을 수거하였으며 칼슘, 철, 아연은 무기성분의 건식분해법으로 전 처리한 후 Inductively Coupled Plasma Spectrometer (ICP)로 실험하였다. 칼슘이 강조표시된 제품 42건에 대한 표시량 비율은 87~176%이 었으며, 철이 강조표시된 제품 13건에 대한 표시량 비율은 84~167%, 아연이 강조표시된 제품 6건에 대한 표시량비율은 98~275%였다. 모든 분석값이 표시량 대비 80% 이상으로 식품 등의 표시기준을 충족하였다. 칼슘과 철의 상호작용은 한국인의 칼슘 섭취가 1일 권장량의 68.7% 수준으로 부족하므로 칼슘의 과다섭취로 인한 철의 흡수방해는 우려할 만한 상황은 아닌 것으로 보인다. 또한, 분석한 영양강조표시제품의 철과 아연의 함량 비율이 1.53:1이 최대였으므로 철의 과다섭취로 인한 아연의 흡수방해는 우려할 만한 상황은 아니었다. 그러나 업체에서는 칼슘, 철, 아연을 강조한제품을 생산할 시에 영양소의 상호작용을 고려하여 생산을 해야 할 것이고 소비자에게 정확한 영양정보를 제공하고 적정량의 영양섭취를 위해서는 지속적인 모니터링을 통해 식품표시에 대한 주기적인 관리가 필요할 것으로 생각된다.
        4,000원
        68.
        2016.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 다래‘대성’과실의 수확 후 품질 보구력과 저장성 증진에 대한 효과를 살펴보고자 칼 슘-키토산을 수확 전후 처리 하였다. 수확 전 처리는 8월 20일, 25일, 28일 3회에 거쳐 과실에 살포 처리하였고, 수확 후 처리는 8월 31일 수확한 건전한 과실을 선별하여 침지 처리하였다. 처리한 과실은 1℃와 17℃ 온도 조건에 저장 하여 시기별로 가용성 고형물 함량, 산함량, 경도, 호흡률, 에틸렌발생량, 감모율을 조사하여 과실 품질을 평가하였다. 두 온도 조건에서 수확전후 칼슘-키토산 처리는 과피에 대 한 코팅효과에 의해 감모율 억제효과를 보였다. 17℃ 저장조건에서는 감모율 이외의 품질지표에서는 처 리간의 유의적인 차이가 없었으나, 1℃ 저장조건에서는 감모율 이외에도 경도와 호흡률에서 칼슘-키토 산 수확 전후처리가 과실 후숙을 억제하는 효과가 있음을 확인 하였다.
        4,000원
        69.
        2016.10 구독 인증기관·개인회원 무료
        The aim of this study was to improve dispersion stability of calcium carbonate (CaCO3) nanoparticles in aqueous medium using alkyl polyglucoside (APG). One hundred milligrams of CaCO3 nanoparticles was mixed with 30 mL of deionized water. Thereafter, APG was dissolved into the CaCO3 nanoparticle mixtures at approximate 0, 0.1, 0.3, 0.5, 0.7, and 0.9%, and subsequently, pH was adjusted to 7.0 and 10.0. Afterward, all CaCO3 nanoparticle mixtures were dispersed by ultrasonic processing treatment for 10 min. Dispersion stability and physicochemical properties of the CaCO3 nanoparticle mixtures were observed by measuring the change of absorbance and mean diameter for 96 h as well as the initial zeta-potential. As results, initial zeta-potentials of the CaCO3 nanoparticles in deionized water at pH 7.0 and 10.0 showed approximately +20 and 0, respectively. The positive surface charge at pH 7.0 had unfavorable impact on the adsorption of APG onto CaCO3 nanoparticles in the aqueous suspensions because APG is nonionic surfactant. Among all samples at pH 10, CaCO3 nanoparticles in 0.5% APG aqueous solution showed the smallest initial mean diameter and the slowest increase in mean diameter and decrease in absorbance. In conclusion, the pH 10.0 and 0.5% APG concentration was the most desirable condition in order to improve dispersion stability of CaCO3 nanoparticles in an aqueous medium.
        70.
        2016.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        An experiment was carried out to determine the effect of cooling water treatment with ionized calcium on calcium content, extending the shelf-life and quality of fresh chicken meat in poultry slaughtering process. The subjects were divided into four groups: control (0% without ionized calcium) and treatment groups (0.5, 0.7, 0.9% ionized calcium). The results indicated that the cooling water treatment with ionized calcium exhibited the bacterial counts of 105 CFU/cm2 in surface of chicken meat, and maintained the quality of fresh chicken meat with extending the shelf-life above seven days when compared with that of control group. The results found that the cooling water treatment with ionized calcium could produce the calcium enrichment of chicken meat as nine times higher in calcium content of chicken meat when compared with that of control group. pH, water holding capacity, TBARS (MDA mg/kg) in chicken meat via the cooling water treatment with ionized calcium showed 6.4, above 50, below 0.10, respectively, with preventing the oxidation of unsaturated fatty acids. Lightness (L*) as a chicken meat color, shear force indicated above 60, below 1.70 kg/0.5 inch2, respectively.
        4,300원
        71.
        2016.07 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Mineral filler is used for resin compounds, because it increases the stiffness and thermal stability of a resin compound, and it also cuts down the cost. Calcium carbonate, silica, magnesium oxide, and others are used as filler materials in general, and the type of filler material, the size, and content can affect the physical properties of compounds. Those factors also influence the viscosity of resin mixtures and the workability, and should be adjusted by changing the contents of the filler, which depends on the size. In this study, five kinds of ground calcium carbonate, which were different in size, were used to produce polyester compounds ; the physical properties were compared with the filler size and contents. The mechanical properties were measured by bending strength and tensile strength, and the heat deflection temperature was obtained for thermal stability.
        3,000원
        72.
        2016.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 액-액 반응에 의한 액상탄산화법을 이용하여 탄산칼슘을 제조하였다. MEA를 사용하여 습식화학수법의 셔틀메카니즘을 도입하였다. MEA 30% 수용액에 고농도 이산화탄소(A)와 배 기가스(B)를 사용하여 이산화탄소를 포집하였으며, 액상탄산화과정을 통해 슬러지 mg 당 0.35 mg의 이 산화탄소를 고정하였다. 최종생성물의 SEM 분석결과 탄산칼슘의 구조는 calcite가 혼합되어 있으나 대 부분 구형 vaterite가 생성되었다.
        4,000원
        73.
        2016.06 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        In this work, recent progress on graphene/metal oxide composites as advanced materials for HgCl2 and CO2 capture was investigated. Density Functional Theory calculations were used to understand the effects of temperature on the adsorption ability of HgCl2 and water vapor on CO2 adsorption on CaO (001) with reinforced carbon-based nanostructures using B3LYP functional. Understanding the mechanism by which mercury and CO2 adsorb on graphene/CaO (g-CaO) is crucial to the design and fabrication of effective capture technologies. The results obtained from the optimized geometries and frequencies of the proposed cluster site structures predicted that with respect to molecular binding the system possesses unusually large HgCl2 (0.1- 0.4 HgCl2 g/g sorbent) and CO2 (0.2-0.6 CO2 g/g sorbent) uptake capacities. The HgCl2 and CO2 were found to be stable on the surface as a result of the topology and a strong interaction with the g-CaO system; these results strongly suggest the potential of CaO-doped carbon materials for HgCl2 and CO2 capture applications, the functional gives reliable answers compared to available experimental data.
        4,000원
        74.
        2016.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to determine the association between dietary calcium intake and biomarkers related to lipid and glucose metabolism and inflammation in Korean patients with type 2 diabetes. Seventy-five subjects (41 males, 34 females) were recruited from a group of patients who had visited the department of endocrine medicine. Data on anthropometric characteristics, clinical indices such as hemoglobin A1c and C-reactive protein (CRP), and dietary nutrient intakes were collected. Subjects were divided into three groups on the basis of their calcium intake [<EAR (below estimated average requirement), EAR-RNI (between EAR and recommended nutrient intake), >RNI (above RNI)]. Average calcium intake of <EAR, EAR-RNI, >RNI groups were 462.7±18.7, 649.7±12.8, and 895.7±21.7 mg, respectively. Energy intake was not different among groups but intakes of protein, total and saturated fatty acids were significantly higher in >RNI group than <EAR group. Analysis of covariance revealed that HDL cholesterol level was significantly higher in EAR-RNI group, as compared to <EAR group after adjustment with confounders such as age, sex, BMI and energy intake (p<0.05). Levels of CRP and homeostasis model assessment 2-insulin resistance (HOMA2-IR) were significantly lower in EAR-RNI group. Total cholesterol level was higher in EAR-RNI and >RNI groups, although within the normal range. Our results suggest that dietary calcium intake may influence the levels of HDL-cholesterol, CRP and HOMA2-IR and subsequently, help management/treatment of type 2 diabetes patients.
        4,000원
        75.
        2016.04 구독 인증기관·개인회원 무료
        본 연구는 수확 후 감귤의 부패과 발생 억제를 위하여 grapefruit seed extract과 oregano oil이 혼입된 carnauba 코팅 과 calcium oxide이 혼입된 chitosan 코팅을 감귤에 적용하여 Penicillium italicium 저해 효과에 대하여 연구하였다. carnauba 수용액(18%(w/w))에 grapefruit seed extract 또는 oregano oil을 단독으로 각각 0.3-1%(w/w) 첨가하였고, grapefruit seed extract과 oregano oil을 0.75:0.25, 0.5:0.5,그리고 0.25:0.75(w/w)의 비율로 혼합하여 첨가하였다. 또한 1% chitosan 수용 액의 경우 0.3-3%(w/w)의 calcium oxide을 첨가하여 코팅제를 개발하였다. 감귤 과피에 접종된 P. italicium에 대한 각 코팅제의 저해 효과는 부패과 발생률(%)로 표현하였다. carnauba wax 코팅의 경우, grapefruit seed extract을 단독으로 1% (w/w) 첨가, grapefruit seed extract과 oregano oil을 혼합하여 0.5:0.5%(w/w) 비율로 첨가하였을 때 부패과 발생률은 각각 23.6%와 25%로 유의적으로 가장 낮았고(P<0.05), calcium oxide을 첨가한 chitosan 코팅의 경우 calcium oxide의 농도와 관계없이 모든 조건에서 부패과 발생률이 유의적 차이를 보이지 않았다(P>0.05). 따라서 grapefruit seed extract 과 oregano oil이 혼입된 carnauba wax 코팅은 감귤의 저장 중 부패에 관여하는 P. italicium를 저해하여 저장성을 향상 시킬 수 있는 것으로 사료되었다.
        76.
        2015.12 구독 인증기관 무료, 개인회원 유료
        Nitric Oxide (NO) is an important signaling molecule in the nociceptive process. Our previous study suggested that high concentrations of sodium nitroprusside (SNP), a NO donor, induce a membrane hyperpolarization and outward current through large conductances calcium-activated potassium (BKca) channels in substantia gelatinosa (SG) neurons. In this study, patch clamp recording in spinal slices was used to investigate the sources of Ca²+ that induces Ca²+-activated potassium currents. Application of SNP induced a membrane hyperpolarization, which was significantly inhibited by hemoglobin and 2-(4-carboxyphenyl) -4,4,5,5- tetramethylimidazoline-1-oxyl-3-oxide potassium salt (c-PTIO), NO scavengers. SNP-induced hyperpolarization was decreased in the presence of charybdotoxin, a selective BKCa channel blocker. In addition, SNP-induced response was significantly blocked by pretreatment of thapsigargin which can remove Ca²+ in endoplasmic reticulum, and decreased by pretreatment of dentrolene, a ryanodine receptors (RyR) blocker. These data suggested that NO induces a membrane hyperpolarization through BKca channels, which are activated by intracellular Ca²+ increase via activation of RyR of Ca²+ stores.
        4,000원
        79.
        2015.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        현대인의 과도한 설탕 섭취, 채소 및 칼슘 섭취 부족 등과 같은 문제점들을 해결하기 위하여 칼슘을 첨가한 무설탕의 과일 채소잼을 제조하였으며, 제조한 제품에 대하여 이화학 적 변화와 관능평가를 실시하였다. 당도는 사과의 농도를 줄 이고, 케일의 함량을 증가시킨 결과, 낮은 당도를 보였으며, 제조한 잼의 pH에서는 당도와는 달리 사과와 케일의 양과는 상관없이 전반적으로 유의적인 차이를 보이지 않았지만, 사 과의 함량이 적을수록 약간 높은 pH를 보이는 것으로 나타났 다. 명도 및 황색도의 경우, 케일 함량이 증가할수록 점점 명 도 및 황색도의 값이 증가하는 경향으로 나타났다. 그러나 적 색도의 값은 -2.05~-1.37로 케일의 함량이 증가한다고 하 여 증가 또는 감소의 경향을 보이지는 않는 것으로 나타났다. 조직감의 경우, 케일의 함량이 증가할수록 경도(hardness), 탄 력성(springiness), 응집성(cohesiveness), 검성(gumminess) 및 씹 힘성(Chewiness)은 유의적으로 감소하는 경향을 보였다. 그 러나 부착성(adhesiveness)은 케일 함량이 증가할수록 증가하 는 경향을 나타내었다. 관능검사의 경우, 10.0~12.0%의 케일 첨가군이 유의적인 차이 없이 가장 높은 기호도를 보였으며, 케일의 농도가 높을수록 맛을 비롯하여 향, 색, 발림성 및 종 합적 기호도는 모두 감소하였다. 이와 같은 결과로 보아 설탕 대신 프락토올리고당으로 대신하고, 식이섬유의 함량이 높은 케일을 첨가하여 잼을 제조할 때 사과와 케일의 비율은 3:1 또는 4:1 정도가 적합할 것으로 판단되었다.
        4,000원
        80.
        2015.09 KCI 등재 구독 인증기관·개인회원 무료
        We present population synthesis models for the calcium II triplet (CaT), currently the most popular metallicity indicator, based on high-resolution empirical spectral energy distributions (SEDs). Our new CaT models, based on empirical SEDs, show a linear correlation below [Fe/H] ~ -0.5, but the linear relation breaks down in the metal-rich regime by converging to the same equivalent width. This relation shows good agreement with the observed CaT of globular clusters (GCs) in NGC 1407 and the Milky Way. However, a model based on theoretical SEDs does not show this feature of the CaT and fails to reproduce observed GCs in the metal-rich regime. This linear relation may cause inaccurate metallicity determination for metal-rich stellar populations. We have also con rmed that the effect of horizontal- branch stars on the CaT is almost negligible in models based on both empirical and theoretical SEDs. Our new empirical model may explain the difference between the color distributions and CaT distributions of GCs in various early-type galaxies. Based on our model, we claim that the CaT is not a good metallicity indicator for simple stellar populations in the metal-rich regime.
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