• Title/Summary/Keyword: $T_{\omega}$

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Effect of Dietary Supplementation of Alisma canaliculatum (Alismatis Rhizoma) and Viscum album (Mistletoe) on Growth Performance and Immunity in Broiler Chickens (택사와 겨우살이 급여가 육계의 생산성 및 면역성에 미치는 영향)

  • Kim, Ki-Soo;Kim, Gwi-Man;Ji, Hoon;Park, Sung-Uk;Yang, Chul-Ju
    • Korean Journal of Poultry Science
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    • v.38 no.1
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    • pp.21-28
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    • 2011
  • This study was conducted to investigate the effect of dietary supplement of Alisma canaliculatum and Viscum album on the growth performance and immune response of broiler chickens. One hundred and forty Ross broiler chicks (1 day old) were assigned to 4 treatments in 5 replications with 7 birds per replication. The dietary treatments were NC group (without antibiotics), PC group (basal + 50 ppm Oxytetracycline), AC group (basal + Alisma canaliculatum 0.5%), and VA group (basal + Viscum album 0.5%). The results revealed that body weight gain and feed intake were not significantly different among the treatments. Addition of AC to the diet showed significantly higher feed conversion ratios than the VA addition diet and other treatments (p<0.05). The concentration of linolenic acid, ${\alpha}$-linolenic acid and arachidonic acid in the AC and VA treatment were relatively higher than that in the antibiotic treatment, while there was no difference in the concentration of SFA, USFA, and USFA/SFA. The serum IgG concentration in chickens tended to increase in the AC and VA treatment groups compared to NC group. The IL2 concentration in AC and VA groups was significantly higher than in other group (p<0.05). IL6 was not detected, however. GOT, GPT, and T-billirubin in the VA group were significantly higher than in other groups (p<0.05). Thus, the VA additives can result in the damage of liver and kidney. In conclusion, the dietary supplement of a 0.5% of AC and VA showed a similar growth performance and increased immunity response comparable to supplementing a 50 ppm Oxytetracycline. Therefore, it can be said that the AC and VA are possible alternates of antibiotics.

Properties of Indium Tin Oxide Thin Films According to Oxygen Flow Rates by γ-FIB System (γ-FIB 시스템을 이용한 산소 유량 변화에 따른 산화인듐주석 박막의 특성 연구)

  • Kim, D.H.;Son, C.H.;Yun, M.S.;Lee, K.A.;Jo, T.H.;Seo, I.W.;Uhm, H.S.;Kim, I.T.;Choi, E.H.;Cho, G.S.;Kwon, G.C.
    • Journal of the Korean Vacuum Society
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    • v.21 no.6
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    • pp.333-341
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    • 2012
  • Indium Tin Oxide (ITO) thin films were prepared by RF magnetron sputtering with different flow rates of $O_2$ gas from 0 to 12 sccm. Electrical and optical properties of these films were characterized and analyzed. ITO deposited on soda lime glass and RF power was 2 kW, frequency was 13.56 MHz, and working pressure was $1.0{\times}10^{-3}$ Torr, Ar gas was fixed at 1,000 sccm. The transmittance was measured at 300~1,100 nm ranges by using Photovoltaic analysis system. Electrical properties were measured by Hall measurement system. ITO thin films surface were measured by Scanning electron microscope. Atomic force microscope surface roughness scan for ITO thin films. ITO thin films secondary electron emission coefficient(${\gamma}$) was measured by ${\gamma}$-Focused ion beam. The resistivity is about $2.4{\times}10^{-4}{\Omega}{\cdot}cm$ and the weighted average transmittance is about 84.93% at 3 sccm oxygen flow rate. Also, we investigated Work-function of ITO thin films by using Auger neutralization mechanism according to secondary electron emission coefficient(${\gamma}$) values. We confirmed secondary electron emission peak at 3 sccm oxygen flow rate.

Effects of High-temperature Annealing of CeO$_2$ Buffer Layers on the Surface Morphology of YBa$_2Cu_3O_{7-{\delta}}$ Films on CeO$_2$-buffered R-cut Sapphire Substrates (CeO$_2$ 완충층에 대한 고온 열처리가 CeO$_2$ 완충층을 지닌 R-cut 사파이어 기판 우에 성장된 YBa$_2Cu_3O_{7-{\delta}}$ 박막의 표면상태에 미치는 영향)

  • Lee, Jae-Hun;Yang, Woo-Il;Jang, Jeong-Mun;Ryu, Jae-Su;Komashko, V.A.;Lee, Sang-Yeong
    • 한국초전도학회:학술대회논문집
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    • v.9
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    • pp.152-159
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    • 1999
  • YBa$_2Cu_3O_{7-{\delta}}$ (YBCO) films grown on CeO$_2$-buffered r-cut sapphire substrates (CbS's) were prepared and their structural and electrical properties were measured. Post-annealed CeO$_2$ films were used as buffer layers for the experiments. It turned out that the YBCO films grown on post-annealed CbS's had the rms roughness of less than 20 ${\AA}$ and peak-to-peak roughness of about 30 ${\AA}$ when the YBCO film thickness was 3000 ${\AA}$. Meanwhile, YBCO films on in-situ grown CeO$_2$ buffer layers on r-cut sapphire substrates appeared to have the peak-to-peak roughness of more than 450 ${\AA}$. X-ray diffraction data revealed that the YBCO flms were epitaxially grown along the c-axis with the typical FWHM of(005) ${\theta}$ -2 ${\theta}$ peak about 0. 16 $^{\circ}$ and ${\Delta}$ ${\omega}$ of the (005) peak about 0.5 $^{\circ}$. T$_c$ > 87 K, ${\Delta}$T < 1 K and R(look)/R(100K) ${\ge}$3 were observed from the YBCO films. Applicability of the YBCO films for high-frequency applications was described.

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Determination of Positional Fatty Acid and Triacylglycerol Compositions of Selected Infant Formulas (영유아용 조제분유의 위치별 지방산 및 Triacylglycerols의 정성 분석)

  • Son, Jeoung-Mae;Lee, Jeung-Hee;Hong, Soon-Taek;Lee, Kyung-Su;Park, Hye-Kyung;Kwon, Kwang-Il;Lee, Ki-Teak
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.9
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    • pp.1256-1264
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    • 2011
  • Infant formula is one of the main nutritional sources for infants. In this study, the fatty acid compositions of Korean (domestic, n=8) and foreign infant formulas (n=3) were analyzed. Crude fats were extracted using the Folch method, and fatty acid compositions (total and positional) were analyzed by gas chromatography. In the fatty acid compositions of infant formulas, oleic (19.88~44.64%), palmitic (7.59~21.65%) and linoleic acids (16.72~25.87%) were the major fatty acids. Domestic infant formula products contained 35.94~56.55% total saturated fatty acid content, whereas that of foreign infant formula ranged from 34.40~42.88%. The content of monounsaturated fatty acids ranged from 20.23~44.99% in domestic products and 34.11~45.07% in foreign products. In addition, 0.17~2.57% arachidonic acid/docosahexaenoic acid and 10~13% linoleic acid/linolenic acid were detected in the analyzed products (domestic and foreign products). A small amount of trans fatty acids (0.25~1.69%) were found. In sn-2 position analysis, palmitic acids (1.84~38.74%) were detected in the analyzed formulas. Further, typical triacylglycerols in human milk, including 1,3-di-monounsaturated-2-saturated triacylglycerol, were not detected in the analyzed formulas.

Magnetic Tunnel Junctions with AlN and AlO Barriers

  • Yoon, Tae-Sick;Yoshimura, Satoru;Tsunoda, Masakiyo;Takahashi, Migaku;Park, Bum-Chan;Lee, Young-Woo;Li, Ying;Kim, Chong-Oh
    • Journal of Magnetics
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    • v.9 no.1
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    • pp.17-22
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    • 2004
  • We studied the magnetotransport properties of tunnel junctions with AlO and AlN barriers fabricated using microwave-excited plasma. The plasma nitridation process provided wider controllability than the plasma oxidization for the formation of MTJs with ultra-thin insulating layer, because of the slow nitriding rate of metal Al layers, comparing with the oxidizing rate of them. High tunnel magnetoresistance (TMR) ratios of 49 and 44% with respective resistance-area product $(R{\times}A) of 3 {\times} 10^4 and 6 {\times} 10^3 {\Omega}{\mu}m^2$ were obtained in the Co-Fe/Al-N/Co-Fe MTJs. We conclude that AlN is a hopeful barrier material to realize MTJs with high TMR ratio and low $R{\times}A$ for high performance MRAM cells. In addition, in order to clarify the annealing temperature dependence of TMR, the local transport properties were measured for Ta $50{\AA} /Cu 200 {\AA}/Ta 50 {\AA}/Ni_{76}Fe_{24} 20 {\AA}/Cu 50 {\AA}/Mn_{75}Ir_{25} 100 {\AA}/Co_{71}Fe_{29} 40 {\AA}/Al-O$ junction with $d_{Al}= 8 {\AA} and P_{O2}{\times}t_{0X}/ = 8.4 {\times} 10^4$ at various temperatures. The current histogram statistically calculated from the electrical current image was well in accord with the fitting result considering the Gaussian distribution and Fowler-Nordheim equation. After annealing at $340^{\circ}C$, where the TMR ratio of the corresponding MTJ had the maximum value of 44%, the average barrier height increased to 1.12 eV and its standard deviation decreased to 0.1 eV. The increase of TMR ratio after annealing could be well explained by the enhancement of the average barrier height and the reduction of its fluctuation.

A Study on the Thermodynamic Characteristics of Dimer Liquid Crystal(CBA-10) by Phase Transition (이량체액정(CBA-10)의 상전이에 따른 열역학적 특성에 관한 연구)

  • Kang, Bong-Geun;Kwak, Son-Yeop;Nam, Su-Yong
    • Applied Chemistry for Engineering
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    • v.8 no.5
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    • pp.796-803
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    • 1997
  • The PVT and $^2H$-NMR characteristic of main-chain dimer liquid crystals having structures such as ${\alpha}$, ${\omega}$-bis[4,4'-cyanobiphenyl) oxy] alkane(CBA-10) were studied. In this work, V-T curves obtained from isobaris measurements on various pressures, volume changes were observed at the nematic-isotropic and nematic-crystal phase transition. The volume changes at the transition exhibit slight odd-even effect with respect to the number of methylene unit n. The values of the$({\Delta}S_{tr})_V$ obtained at the NI transition for CBA-10 was $12.6J/mol{\cdot}K$. The values of $({\Delta}S_{CN})_V$ for the CN transition was estimated on the basis of DSC data : $65.3J/mol{\cdot}K$. For both transition, it was found that the correction about the volume change is significant, ranging from 40 to 60% of the total transition entropy observed under constant pressure. The RIS analysis of the spectra was performed so as to elucidate the conformational characteristics of the spacer in the nematic phase. The conformational entropy changes at both CN and NI interphases were estimated on the basis of the nematic conformations taken from the conformation map as well as those derived from the simulation. The estimated conformational entropy change values were then compared with the corresponding constant-volume entropies obtained from PVT measurements. The correspondence between both entropy values was found to be quite good in consideration of the uncertainties involved in both experiment and calculations.

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Effects of Crataegii fructus on the Contractile Response of Rabbit Corpus Cavernosum (산사(山査)가 토끼 음경해면체의 수축에 미치는 영향)

  • Lee, Han Seok;Park, Sun Young
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.27 no.5
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    • pp.602-610
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    • 2013
  • This study was aimed to evaluate the cavernosal relaxation effect of Crataegii fructus(CF) in the contracted rabbit penile corpus cavernosum by agonists.In order to study the effect of CF on the vasoconstriction of rabbit penile corpus cavernosum, isolated rabbit penile corpus cavernosum tissues were used for the experiment using organ baths containing Krebs solution.To investigate the cavernosal relaxation of CF, CF extract at $0.01{\sim}3.0mg/m{\ell}$ was added after penile corpus cavernosum were contracted by norepinephrine(NE) $1{\mu}M$. To analyze the mechanism of CF's vasorelaxation, CF extract infused into contracted penile tissues by NE after each treatment of indomethacin(IM), $N{\omega}$-nitro-L-arginine(L-NNA), methylene blue(MB), tetraethylammonium chloride(TEA).To study the effect of CF on influx of extracellular calcium chloride($Ca^{2+}$) in penile tissues, in $Ca^{2+}$-free krebs solution, $Ca^{2+}$ 1 mM infused into contracted penile tissues by NE after pretreatment of CF. Cytotoxic activity of CF on human umbilical vein endothelial cell(HUVEC) was measured by MTT assay, and nitric oxide(NO) prodution was measured by Griess reagent. CF relaxed cavernosal strip with endothelium contracted by NE, but in the strips without endothelium, CF-induced relaxation was significantly inhibited. The pretreatment of L-NNA, MB, TEA decreased significantly on the cavernosal relaxation than not-treatment of them. But the pretreatment of IM had no significant effect on the cavernosal relaxation. In $Ca^{2+}$-free krebs solution, when $Ca^{2+}$ infused into contracted penile tissues by NE, pretreatment of CF inhibit contraction induced by adding $Ca^{2+}$.NO production wasn't increased by treatment of CF on HUVEC. This findings showed that CF is effective for the relaxation of rabbit penile corpus cavernosum, and we suggest that CF relax rabbit corpus cavernosal smooth muscle through multiple action mechanisms that include increasing the release of nitric oxide from corporal sinusoidal endothelium, inhibition of $Ca^{2+}$ mobilization into cytosol from the extracellular fluid, and maybe a hyperpolarizing action.

A Study on the Formation fo Epitaxial $CoSi_2$ Thin Film using Co/Ti Bilayer (Co/Ti이중박막을 이용한 $CoSi_2$에피박막형성에 관한 연구)

  • Kim, Jong-Ryeol;Bae, Gyu-Sik;Park, Yun-Baek;Jo, Yun-Seong
    • Korean Journal of Materials Research
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    • v.4 no.1
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    • pp.81-89
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    • 1994
  • Ti film of lOnm thickness and Co film of 18nm thickness were sequentially e-heam evaporated onto Si (100) substrates. Metal deposited samples were rapidly thermal-annt.aled(KTA) in thr N1 en vironment a t $900^{\circ}C$ for 20 sec. to induce the reversal of metal bilayer, so that $CoSi_{2}$ thin films could be formed. The sheet resistance measured by the 4-point probe was 3.9 $\Omega /\square$This valur was maintained with increase in annealing time upto 150 seconds, showing high thermal stab~lity. Thc XRII spectra idrn tified the silicide film formed on the Si substrate as a $CoSi_{2}$ epitaxial layer. The SKM microgr;iphs showed smooth surface, and the cross-sectional TKM pictures revealed that the layer formed on the Si substrate were composed of two Co-Ti-Si alloy layers and 70nm thick $CoSi_{2}$ epl-layer. The AES analysis indicated that the native oxide on Si subs~rate was removed by TI ar the beginning of the RTA, and Ihcn that Co diffused to clean surface of Si substrate so that epitaxial $CoSi_{2}$ film could bt, formed. In thc rasp of KTA at $700^{\circ}C$. 20sec. followed by $900^{\circ}C$, 20sec., the thin film showed lower sheet resistance, but rough surface and interface owing to $CoSi_{2}$ crystal growth. The application scheme of this $CoSi_{2}$ epilayer to VLSI devices and the thermodynarnic/kinetic mechan~sms of the $CoSi_{2}$ epi-layer formation through the reversal of Co/Ti bdayer were discussed.

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Fabrication and Characterization of NiMn2O4 NTC Thermistor Thick Films by Aerosol Deposition (상온 진공 분말 분사법에 의한 NiMn2O4계 NTC Thermistor 후막제작 및 특성평가)

  • Baek, Chang-Woo;Han, Gui-fang;Hahn, Byung-Dong;Yoon, Woon-Ha;Choi, Jong-Jin;Park, Dong-Soo;Ryu, Jung-ho;Jeong, Dae-Yong
    • Korean Journal of Materials Research
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    • v.21 no.5
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    • pp.277-282
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    • 2011
  • Negative temperature coefficient (NTC) materials have been widely studied for industrial applications, such as sensors and temperature compensation devices. NTC thermistor thick films of $Ni_{1+x}Mn_{2-x}O_{4+{\delta}}$ (x = 0.05, 0, -0.05) were fabricated on a glass substrate using the aerosol deposition method at room temperature. Resistance verse temperature (R-T) characteristics of the as-deposited films showed that the B constant ranged from 3900 to 4200 K between $25^{\circ}C$ and $85^{\circ}C$ without heat treatment. When the film was annealed at $600^{\circ}C$ 1h, the resistivity of the film gradually decreased due to crystallization and grain growth. The resistivity and the activation energy of films annealed at $600^{\circ}C$ for 1 h were 5.203, 5.95, and 4.772 $K{\Omega}{\cdot}cm$ and 351, 326, and 299 meV for $Ni_{0.95}Mn_{2.05}O_{4+{\delta}}$, $NiMn_2O_4$, and $Ni_{1.05}Mn_{1.95}O_{4+{\delta}}$, respectively. The annealing process induced insulating $Mn_2O_3$ in the Ni deficient $Ni_{0.95}Mn_{2.05}O_{4+{\delta}}$ composition resulting in large resistivity and activation energy. Meanwhile, excess Ni in $Ni_{1.05}Mn_{1.95}O_{4+{\delta}}$ suppressed the abnormal grain growth and changed $Mn^{3+}$ to $Mn^{4+}$, giving lower resistivity and activation energy.

Microstructure and Positive Temperature Coefficient of Resistivity Characteristics of Na2Ti6O13-Doped 0.94BaTiO33-0.06(Bi0.5Na0.5)TiO3 Ceramics (Na2Ti6O13를 도핑한 0.94BaTiO3-0.06(Bi0.5Na0.5)TiO3 세라믹스의 미세구조와 Positive Temperature Coefficient of Resistivity 특성)

  • Cha, Yu-Joung;Jeong, Young-Hun;Lee, Young-Jin;Paik, Jong-Hoo;Lee, Wu-Young;Kim, Dae-Joon
    • Korean Journal of Materials Research
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    • v.20 no.11
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    • pp.575-580
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    • 2010
  • The microstructure and positive temperature coefficient of resistivity (PTCR) characteristics of 0.1 mol%$Na_2Ti_6O_{13}$ doped $0.94BaTiO_3-0.06(Bi_{0.5}Na_{0.5})TiO_3$ (BBNT-NT001) ceramics sintered at various temperatures from $1200^{\circ}C$ to $1350^{\circ}C$ were investigated in order to develop eco-friendly PTCR thermistors with a high Curie temperature ($T_C$). Resulting thermistors showed a perovskite structure with a tetragonal symmetry. When sintered at $1200^{\circ}C$, the specimen had a uniform microstructure with small grains. However, abnormally grown grains started to appear at $1250^{\circ}C$ and a homogeneous microstructure with large grains was exhibited when the sintering temperature reached $1325^{\circ}C$. When the temperature exceeded $1325^{\circ}C$, the grain growth was inhibited due to the numerous nucleation sites generated at the extremely high temperature. It is considered that $Na_2Ti_6O_{13}$ is responsible for the grain growth of the $0.94BaTiO_3-0.06(Bi_{0.5}Na_{0.5})TiO_3$) ceramics by forming a liquid phase during the sintering at around $1300^{\circ}C$. The grain growth of the BBNT-NT001 ceramics was significantly correlated with a decrease of resistivity. All the specimens were observed to have PTCR characteristics except for the sample sintered at $1200^{\circ}C$. The BBNT-NT001 ceramics had significantly decreased $\tilde{n}_{rt}$ and increased resistivity jump with increasing sintering temperature at from $1200^{\circ}C$ to $1325^{\circ}C$. Especially, the BBNT-NT001 ceramics sintered at $1325^{\circ}C$ exhibited superior PTCR characteristics of low resistivity at room temperature ($122\;{\Omega}{\cdot}cm$), high resistivity jump ($1.28{\times}10^4$), high resistivity temperature factor (20.4%/$^{\circ}C$), and a high Tc of $157.9^{\circ}C$.