• Title/Summary/Keyword: Ca/S ratio

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Effects of Rapid Thermal Annealing on Thermal Stability of FeMn Spin Valve Sensors

  • Park, Seung-Young;Choi, Yeon-Bong;Jo, Soon-Chul
    • Journal of Magnetics
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    • v.10 no.2
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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.

Studies on the Fusibility of Fly Ash-Flux Mixtures (융제 첨가 비산회의 융융성 연구)

  • Yang, Hyun S.;Lee, Kyu C.;Park, Chu S.
    • Applied Chemistry for Engineering
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    • v.8 no.6
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    • pp.985-993
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    • 1997
  • The effects of CaO and MgO fluxes on the fusibility of fly-ashes were investigated for two different fly-ashes. A fusion temperature of mixtures of selected fly-ashes and fluxes were measured by the ASTM test method(D1857) and the differential thermal analysis. IDT of these samples added CaO and MgO as a fluxing agent dropped in the range of 114 to $294^{\circ}C$ and 80 to $224^{\circ}C$, respectively. Compared with ash fusion temperature to Base/Acid ratio, the lowest ash fusion temperature were measured in the range of 0.7 to 0.8 for CaO-fly ash mixtures and 0.3 to 0.4 for MgO-fly ash mixtures. As a result, MgO in small addition acted as a more effective flux than CaO. A conventional Base/Acid ratio and liquidus point of ternary diagram did not show a good correlation with ash fusion temperature for these samples. In pure fusion temperature of fly ash-mixtures, DTA was better method than ASTM test method.

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Dietary effect of silk protein on epidermal levels of free sphingoid bases and phosphate metabolites in NC/Nga mice (실크 단백질의 식이 공급이 아토피 피부염 동물 모델 NC/Nga Mice 표피의 스핑고이드 베이스 및 인산화물 함량 변화에 미치는 영향)

  • Kim, Young-Ae;Song, Eun-Hwa;Shin, Kyoung-Oh;Lee, Yong-Moon;Cho, Yun-Hi
    • Journal of Nutrition and Health
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    • v.45 no.2
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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.

Parameters for Predicting Granulosa Cell Tumor of the Ovary: A Single Center Retrospective Comparative Study

  • Yesilyurt, Huseyin;Tokmak, Aytekin;Guzel, Ali Irfan;Simsek, Hakki Sencer;Terzioglu, Serdar Gokay;Erkaya, Salim;Gungor, Tayfun
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.19
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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.

Study on the Eco-friend Frame Sheet with Improved Glasses Temple's Insertion-processibility by Blending Plasticizer of High Specific Heat (친환경 안경테 판재의 심입 가공성 향상을 위한 고비열 가소제 혼입에 관한 연구)

  • Seo, Young Min;Lee, Hae Sung;Lee, Sung Jun;Jung, Sang Won;Kim, Hyun-Chul;Kim, Eun Joo;Go, Young Jun;Choi, Jin Hyun;Lee, Se Guen
    • Journal of Korean Ophthalmic Optics Society
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    • v.18 no.1
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    • pp.11-17
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    • 2013
  • Purpose: To improve glasses temple's insert processibility of CA/PEG blend, triacetin with higher specific heat values in the processing temperature range is used as second plasticizer. Methods: The total amount of plasticizer is fixed at 30 wt% by CA. To determine optimal CA/PEG/triacetin blend for glasses frame, blends with different composition ratio were examined by various analysis: thermal properties, mechanical properties, glossiness. Results: Specific heat of the CA/PEG blend increased as the content of triacetin. In CA/PEG/triacetin blends, as triacetin concentration is increased, glass transition temperature is decreased and heat conservation rate of composites is increased. Furthermore, CA/PEG/triacetin blend exhibited higher mechanical properties and similar gloss characterization with CA/PEG blend. Conclusions: It is possible to improve the processibility inserting metal support to CA temple through varying the weight ratio of PEG/triacetin. The extruded sheets of CA/PEG/triacetin blend had better glossiness and mechanical properties than those of CA/PEG blend.

A Study on the Hydrothermal Synthesis of Tobermorite in the System of CaO-SiO2-H2O and Cement Sludge-SiO2-H2O (생석회-규사-수계 및 시멘트 슬러지-규사-수계에서 Tobermorite의 수열합성에 관한 연구)

  • Rho, Jae-Seong;Hong, Seong-Su;Cho, Heon-Young;Choi, Sang-Won
    • Applied Chemistry for Engineering
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    • v.4 no.2
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    • pp.291-299
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    • 1993
  • Hydrothermal synthesis of 1.13nm tobermorite was performed to obtain the mixing ratio of raw materials, the optimum reaction time and the effect of aluminum in two systems, $CaO-SiO_2-H_2O$ and cement sludge-$SiO_2-H_2O$. 1.13nm tobermorite($5CaO{\cdot}6SiO_2{\cdot}5H_2O:C_5S_6H_5$) was synthesized excellently from $CaO-SiO_2-H_2O$ system on each mole ratio (0.4, 0.8) of $CaO/SiO_2$ at $180^{\circ}C$. But a tobermorite crystals had a sign of crystal conversion after 6 hours of reaction times in the case of $CaO/SiO_2=0.4$ and 4 hours of reaction time in the case of $CaO/SiO_2=0.8$. However, a tobermorite synthesized from cement sludge wastes did not show the crystal conversion on each mole ratio(0.4, 0.8) of $CaO/SiO_2$ within 10 hours of reaction times. It is considered that aluminum ions dissolved from cement sludge wastes retarded the recrystallization of tobermorite. This role of aluminum ion was confirmed in $CaO-SiO_2-H_2O+Al$ powder system. According as added amount of Al powder was increased from 0.8% to 3.0%, the crystal had a highly flatter and larger shape. Recrvstallization was not detected within the same reaction times when aluminum was added.

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Effect of NaCl Concentration on Photosynthesis and Mineral Content of Barley Seedlings under Solution Culture

  • Cho, Jin-Woong;Kim, Choong-Soo
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.43 no.3
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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.

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Effect of Surface Modification of Calcium Carbonate Nanoparticles by Octyltrimethoxysilane on the Stability of Emulsion and Foam (실란 커플링제 옥틸트리메톡시실란에 의해 표면 개질된 탄산칼슘 나노입자가 에멀젼 및 기포 안정성에 미치는 영향)

  • Lim, Jong Choo;Park, Ki Ho;Lee, Jeong Min;Shin, Hee Dong
    • Applied Chemistry for Engineering
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    • v.33 no.4
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    • pp.386-393
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    • 2022
  • In this study, the surface modification of calcium carbonate (CaCO3) nanoparticles by a silane coupling agent, octyltrimethoxysilane (OTMS), was investigated and characterized using Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) analysis. Both floating tests and contact angle measurements were also conducted to study the effect of OTMS concentration on the hydrophobicity of CaCO3 nanoparticles. It was found that the active ratio for the CaCO3 nanoparticles modified by 1 wt% of OTMS was 97.0 ± 0.5%, indicating that OTMS is a very effective silane coupling agent in enhancing the hydrophobicity of the CaCO3 nanoparticle surface. The most stable foam was generated with 1 wt% of CaCO3 nanoparticles in aqueous solutions at 1 wt% of OTMS, where the contact angle of water was found to be 91.8 ± 0.7°. It was also found that the most stable emulsion drops were formed at the same OTMS concentration. These results suggest that CaCO3 nanoparticles modified by a silane coupling agent OTMS are a powerful candidate for a foam stabilizer or an emulsifier in many industrial applications.

INTERACTION OF CALCIUM, PHOSPHORUS AND PROTEIN IN BROILERS

  • Ryu, Y.S.;Han, I.K.;Kim, I.B.
    • Asian-Australasian Journal of Animal Sciences
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    • v.7 no.4
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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).

Gender-Related Differences in a Process of the Age-Dependent Alterations of the Elements in Monkey Sino-Atrial Node

  • Satoh, Hiroyasu;Tohno, Setsuko;Minami, Takeshi;Oishi, Takao;Hayashi, Motoharu;Tohno, Yoshiyuki
    • The Korean Journal of Physiology and Pharmacology
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    • v.14 no.5
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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.