• Journal of Magnetics
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• 제10권2호
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• pp.52-57
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• 2005

In this research, magnetoresistance (MR) ratio (MR), resistivity, and exchange coupling field $(H_{ex})$ behaviors for sputter deposited spin valves with FeMn antiferromagnetic layer have been extensively investigated by rapid thermal annealing (RTA) as well as conventional annealing (CA) method. 10 s of RTA revealed that interdiffusion was not significant up to $325^{\circ}C$ at the interfaces between the layers when the RTA time was short. The MR of FeMn spin valves were reduced when the spin valves were exposed to temperature of $250^{\circ}C$, even for a short time period of 10 s prior to CA. $H_{ex}$ was maintained up to $325^{\circ}C$ of CA when the specimen was subjected to 10 s of RTA at $200^{\circ}C$ prior to CA, which is $25^{\circ}C$ higher than the result obtained from the CA without prior RTA. Therefore, the stability of $H_{ex}$ could be enhanced by a prior RTA before performing CA up to annealing temperature of $325^{\circ}C$. MR and sensitivity of the specimens annealed without magnetic field up to $275^{\circ}C$ were recovered to the values prior to CA, but $H_{ex}$ was not recovered. This means that reduced MR sensitivity and MR during the device fabrication can be recovered by a field RTA.

• 공업화학
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• 제8권6호
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• pp.985-993
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• 1997

구성분이 상이한 2종의 비산회를 대상으로 CaO와 MgO융제의 첨가시 용융온도변화에 대하여 고찰하였다. 용융온도측정을 위하여 ASTM 용융온도측정법과 시차열분석법이 사용되었다. CaO융제의 첨가시 시료에 따라 $111{\sim}294^{\circ}C$의 융점(IDT)강하효과를 얻을 수 있었으며 MgO첨가시에는 $80{\sim}224^{\circ}C$의 융점강하효과를 보였다. Base/Acid Ratio와의 비교에서 CaO flux는 0.7~0.8, MgO flux는 0.3~0.4의 범위에서 가장 낮은 용융온도로 측정되었다. 따라서 적은 첨가량으로도 MgO는 CaO보다 더 효과적인 융제로 작용하였다. 이러한 융제첨가시의 용융온도 변화는 용융성 분석에 보편적으로 사용되어지는 Base/Acid ratio와는 상관성이 없음을 알 수 있었고 $XO-SiO_2-Al_2O_3$ [X=Ca, Mg]삼성분계의 liquidus 온도와도 일치하지 않음을 알 수 있었다. 시차열분석결과와 ASTM용융온도와의 비교에서 용융성과 흐름성(점성)등의 물성이 복합적으로 반영되어 있는 ASTM측정법 보다는 시차열분석이 비산회의 순수한 용융온도를 분석할 수 있는 측정법임을 확인할 수 있었다.

• Journal of Nutrition and Health
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• 제45권2호
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• pp.113-120
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• 2012

In our previous studies, dietary supplements of silk protein, sericin, and fibroin, were beneficial for improving epidermal levels of ceramides, which are the major lipids for maintaining the epidermal barrier. In this study, we investigated the dietary effects of silk protein on epidermal levels of free sphingoid bases and their phosphates such as $C_{18}$ sphingosine (So), $C_{18}$ sphinganine (Sa), $C_{18}$ sphingosine-1-phosphate (S1P), and $C_{18}$ sphinganine-1-phosphate (Sa1P), which are either synthetic substrate or degradative metabolites of ceramides. Forty-five male NC/Nga mice, an animal model of atopic dermatitis (AD), were divided into three groups: group CA was an atopic control and fed a control diet, group S was fed a 1% sericin diet, and group F was fed a 1% fibroin diet. Fifteen male BALB/c mice served as group C (control group) and were fed the control diet. All mice were fed with diets and water $ad$ $libitum$ for 10 weeks. Sa in group CA was lower than that in group C, but So in group CA was similar to that in group C. So and Sa were higher in groups S and F than those in group CA; So level was even higher than that in group C, and Sa level was similar to that of group C. The So/Sa ratio in group CA, which is reported to increase in AD, was significantly higher than that of group C. The So/Sa ratio was lower in groups S and F than that in group CA, and decreased further in group F. However, S1P and Sa1P in groups S and F were similar to those in group CA. Taken together, we demonstrated that silk protein, sericin and fibroin dietary supplements, increased So and Sa levels, and decreased the So/Sa ratio.

• Asian Pacific Journal of Cancer Prevention
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• 제15권19호
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• pp.8447-8450
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• 2014

Background: To evaluate factors for predicting the granulosa cell tumor of the ovary (GCTO) pre-operatively. Materials and Methods: This retrospective designed study was conducted on 34 women with GCTO as the study group and 76 women with benign ovarian cysts as the control group. Data were recorded from the hospital database and included age, body mass index (BMI), parity, serum estradiol ($E_2$) levels, diameter of the mass, ultrasonographic features, serum CA125 level, risk of malignancy index (RMI), duration of menopause, postoperative histopathology result, and the neutrophil/lymphocyte ratio (NLR). Results: The demographic parameters showed no statistically significant difference between the groups. Preoperative diameter of the mass, CA125, duration of menopause, and neutrophil/lymphocyte ratio were significantly different between the groups. ROC curve analysis demonstrated that diameter of the mass, serum estradiol and Ca125 levels, RMI and NLR may be discriminative factors in predicting GCTO preoperatively. Conclusions: In conclusion, we think that a careful preoperative workshop including diameter of the mass, serum estradiol ($E_2$) and Ca125 levels, RMI and NLR may predict GCTO and may prevent incomplete approaches.

• 한국안광학회지
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• 제18권1호
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• pp.11-17
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• 2013

목적: 본 연구는 cellulose acetate/poly ethylene glycol(CA/PEG) 안경테용 판재의 심입가공성을 향상시키기 위하여 심입가공온도 영역에서 비교적 높은 비열을 갖는 친환경 가소제인 triacetin을 2차 가소제로 도입함으로써 가공 효율이 향상 된 친환경 안경테 판재를 제조하는데 목적이 있다. 방법: 전체 가소제의 양을 CA 대비 30 wt%로 고정하고 1차 가소제인 PEG와 2차 가소제인 triacetin의 함량을 조절하여 제조된 CA/PEG/triacetin 조성물의 비열 및 열적특성을 분석하고, 다양한 기계적 물성과 광학적 특성의 비교분석을 통해 우수한 가공성을 갖는 안경테 소재를 위한 최적의 가소제 조성을 결정하였다. 결과: Triacetin 도입을 통해 CA 판재의 비열 상승을 확인하였으며, triacetin 함량비가 증가할수록 유리전이온도(Tg)가 낮아지고 심입가공성의 척도가 되는 감온속도의 감소를 확인하였다. 또한 기존의 CA/PEG 안경테 소재와 비교 시 우수한 광택특성 및 경도를 확인하였으며, 동등수준 이상의 기계적 물성을 보임을 확인하였다. 결론: PEG/triacetin의 투입비율을 조절하여 심입가공성을 향상시키고, 안경테 판재로 사용되기 적합한 물성 및 특유의 광택과 우수한 심미성을 만족하는 CA 판재를 제조할 수 있다.

• 공업화학
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• 제4권2호
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• pp.291-299
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• 1993

생석회-규사-수계 및 시멘트 슬러지-규사-수계에서 1.13nm tobermorite를 수열합성하였다. 생석회-규사-수계의 경우 반응온도 $180^{\circ}C$, $CaO/SiO_2$의 몰비 0.4, 0.8에서 공히 양질의 tobermorite($5CaO{\cdot}6SiO_2{\cdot}5H_2O:C_5S_6H_5$)가 형성되었으나 $CaO/SiO_2$의 몰비 0.4일 때는 반응시간 6시간에서, 0.8일 때는 4시간에서 결정전이 현상이 관찰되었다. 그러나 시멘트 슬러지를 생석회 대신 전량 사용한 시멘트 슬러지-규사-수계는 동일한 몰비에서 반응시간 10시간 이내에 결정전이 현상이 나타나지 않았는데 이는 시멘트 슬러지로부터 용출되어 나온 알루미늄 이온의 지연작용으로 판단되며 생석회-규사-수+알루미늄계에서 확인되었다. 알루미늄 분말의 첨가량이 0.8에서 3.0%로 증가함에 따라 결정은 보다 넓고 평평하게 형성되었다. 또한 동일한 반응시간 내에서 재결정화 현상이 관찰되지 않았다.

• 한국작물학회지
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• 제43권3호
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• pp.152-156
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• 1998

This study was conducted to elucidate the changes of photosynthetic ability and cation content in barley cultivar seedlings cultured for 10 and 30 days with different NaCl concentrations containing 1/4 Hoagland solutions. At the highest NaCl concentration, the weight of dry matter and the shoot/root ratio (S/R ratio) were decreased. Thus, shoots were affected more than roots by NaCl treatment. The S/R ratio decreased more in 'Neulssalbori' than in 'Bunong' by the NaCl treatment. The. internal $Na^+$ concentration increased greatly with the highest NaCl concentration, but $K^+$ concentration in plants decreased with the highest NaCl treatment. The $Ca^{2+}$ concentration had a small change with NaCl concentrations. Thus $Na^+$/$K^+$and $Na^+$/$Ca^{2+}$ratios increased with the highest concentration. The chlorophyll content (%/dry weight) of seedlings decreased at higher NaCl levels except for Bunong in 30 day old seedlings. The photosynthetic ability decreased only for Neulssalbori in the 10 days NaCl treatment. The stomatal conductance, and transpiration had decreased in the 10 day old seedlings, but not with 30 day old seedlings.

• 공업화학
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• 제33권4호
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• pp.386-393
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• 2022

본 연구에서는 실란 커플링제 옥틸트리메톡시실란(octyltrimethoxysilane, OTMS)을 사용하여 친수성 탄산칼슘(CaCO₃) 나노입자의 표면을 개질하였으며, OTMS에 의한 CaCO₃ 나노입자의 표면 개질은 FT-IR, DSC, XRD XPS 및 TGA 분석을 통하여 확인하였다. 또한 부유 시험과 접촉각 측정을 통하여 OTMS 농도가 CaCO₃ 나노입자의 표면 소수성 변화에 미치는 영향에 관하여 살펴보았다. 부유 시험 결과에 따르면 1 wt% OTMS 농도 조건에서 측정한 active ratio 값이 97.0 ± 0.5%로서, OTMS가 CaCO₃ 나노입자 표면을 매우 효율적으로 소수화 개질하는 실란 커플링제임을 알 수 있었다. 또한 OTMS로 개질된 CaCO₃ 나노입자 1 wt%를 함유하는 수용액에 대한 기포 안정성 측정 결과, OTMS 농도가 1 wt%인 조건에서 가장 안정한 기포가 생성되며, 접촉각은 91.8 ± 0.7°임을 확인하였다. 또한 동일한 1 wt% OTMS 농도 조건에서 에멀젼 입자 크기가 가장 작은 안정한 상태의 에멀젼이 형성됨을 확인하였다. 이러한 결과들은 OTMS로 개질된 CaCO₃ 나노입자가 다양한 산업 응용 분야에서 기포 안정화제 및 에멀젼 유화제로서 적용이 가능함을 의미하는 것이다.

• Asian-Australasian Journal of Animal Sciences
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• 제7권4호
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• pp.583-589
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• 1994

In order to study the interrelationships of calcium (0.45 vs. 0.90%), phosphorus (0.40 vs. 0.70%) and protein (17, 20, 23%), $2{\times}2{\times}3$ factorial design was employed. A total of 480 broilers (Hisex-Hibro) aged 3 days were fed the experimental diets for a period of 28 days. Body weight gain, daily feed intake and feed efficiency were investigated for the simple effects, first order interaction and second order interaction of the dietary factors. These effects were also applied to bone ash retention, percent Ca in bone & ash, percent P in bone & ash, and protein utilizability. Results were as follows. 1) For body weight gain, simple effects of dietary levels of Ca, P, CP were found to be significant (p<0.05). Body weight gain at 0.90% Ca level was improved as the dietary CP levels increased. For the feed intake, single effects of dietary levels of both P and CP were found (p<0.05). Feed efficiency was improved as the dietary CP and P levels increased. Ca $\times$ P interaction was found to be significant for body weight gain, feed intake and feed efficiency (p<0.05), however, Ca $\times$ P $\times$ CP interaction effect was not found. 2) Protein utilizability decreased as the dietary CP level increased (p<0.01). 3) 0.90% Ca in diet showed less bone ash retention than 0.45% Ca level. And, increasing the dietary P level resulted in increased bone ash retention. Increasing the dietary P level resulted in increased bone Ca retention (p<0.01) and increased bone P retention (p<0.05). Dietary CP levels had significant (p<0.01) effect on bone Ca retention except for 23% CP level. Increasing the dietary Ca level resulted in wider Ca:P ratio of bone, but increasing the dietary P level resulted in narrower Ca:P ratio of bone. 4. Ca $\times$ P interaction effects were found to be significant (p<0.01) for bone ash, bone Ca & P, ash P content, and bone Ca:P ratio. Ca $\times$ P $\times$ CP interaction effects were found for bone ash (p<0.01), bone Ca (p<0.05) and bone P content (p<0.01).

• The Korean Journal of Physiology and Pharmacology
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• 제14권5호
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• pp.249-256
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• 2010

Gender differences in the trace elements of monkey sino-atrial (SA) node were investigated in a process of age-dependent alterations. Sixty hearts from Japanese and rhesus monkeys (30 male and 30 female) used were aged ranging from 1-day- to 30-year-old. The elements were analyzed using an inductively coupled plasma-atomic emission spectrometer (ICP-AES). Advancing age decreased all the trace elements. Ca, P, S and Mg significantly decreased. The correlation coefficients of Ca and P were $-0.178{\pm}0.081$ (p<0.05) and $-0.088{\pm}0.022$ (p<0.05) in male (n=30), and $-0.095{\pm}0.026$ (p<0.05) and $-0.069{\pm}0.017$ (p<0.05) in female (n=30), respectively. The age-dependent coefficients for Fe/Ca, Zn/Ca, Fe/P, Fe/S, Zn/S, Fe/Mg and Zn/Mg were exhibited markedly in male, but all was less in female. In gender-related differences, only a ratio of P/Ca (p<0.05) was significantly observed with ageing. The trace elements such as Cu, Se and Sn were less detected in the SA nodes. These results indicate that the age-dependent changes in the ratios of elements are appeared more rapidly in male monkey SA node, and the gender difference is observed in ratio of P/Ca. The different attenuations may be involved with the age- and gender-related SA nodal functions.