• Title/Summary/Keyword: SmCo

Search Result 319, Processing Time 0.027 seconds

Luminescent Properties and Anti-Counterfeiting Applications of SrWO4:RE3+ (RE=Dy, Sm, Dy/Sm) Phosphors Doped with Several Activator Ions (다양한 활성제 이온이 도핑된 SrWO4:RE3+ (RE=Dy, Sm, Dy/Sm) 형광체의 특성과 위조 방지 응용)

  • Yoon, Soohwan;Cho, Shinho
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.33 no.5
    • /
    • pp.393-399
    • /
    • 2020
  • A series of phosphors, SrWO4:5 mol% Dy3+, SrWO4:5 mol% Sm3+, and SrWO4:5 mol% Dy3+:x Sm3+ (x=1~15 mol%), were prepared using a facile co-precipitation. The crystal structure, morphology, photoluminescence properties, and application in anti-counterfeiting fields were investigated. The crystalline structures of the prepared phosphors were found to be tetragonal systems with the dominant peak occurring at the (112) plane. The excitation spectra of the Dy3+ singly-doped SrWO4 phosphors were composed of an intense charge-transfer band centered at 246 nm in the range of 210~270 nm and two weak peaks at 351 nm and 387 nm due to the 6H15/26P7/2 and 6H15/24I13/2 transitions of Dy3+ ions, respectively. The wavelength of 246 nm was optimum for exciting the luminescence of Dy3+ and Sm3+ co-doped SrWO4 phosphors. The emission spectra consisted of two intense blue and yellow emission bands at 480 nm and 573 nm corresponding to the 4F9/26H15/2 and 4F9/26H13/2 transitions of Dy3+, and two strong emission peaks at 599 nm and 643 nm originating from the 4G5/26H7/2 and 4G5/26H9/2 transitions of Sm3+, respectively. As the concentration of Sm3+ ions increased, the emission intensities of Dy3+ rapidly decreased, while the emission intensities of Sm3+ gradually increased. These results suggest that the color of the emission light can be tuned from yellow to white by changing the concentration of Sm3+ ions at a fixed 5 mol% Dy3+. Furthermore, the fluorescent security inks were synthesized for use in anti-counterfeiting applications.

Functional Properties of Hydrolysate Soy Milk and Whole Soy Milk (두유와 전두유 가수분해물의 기능적 특성)

  • Jang, Se-Young;Sin, Kyung-A;Park, Nan-Young;Bang, Kwang-Woong;Kim, Jeong-Hoon;Jeong, Yong-Jin
    • Food Science and Preservation
    • /
    • v.15 no.3
    • /
    • pp.361-366
    • /
    • 2008
  • This study was investigated the functional characteristic change by the enzymatic hydrolysate to improve the functionality of soybean milk. The soymilk (SM), hydrolysates of soy milk (HSM), whole soy milk (WSM) and hydrolysates of whole soy milk (HWSM) revealed composition difference whether the bean-curd removal was included or not, but nearly no change was found by the low molecule enzyme treatment. The chromaticity revealed clear difference whether the bean-curd was removed or not, but did not show any difference by the hydrolyzation. Total free sugar and oligosaccharide content was found to be 1,389.88 mg% in SM, 1,013.51 mg% in HSM, 1,539.51 mg% in WSM, and 1,331.53 mg% in HWSM by showing the reduction after the enzyme hydrolyzation. DPPH free radical scavenging activity revealed to show high activity in HSM and in HWSM which were enzymatically hydrolyzed by 49.26% and 45.34%, respectively. And the ACE inhibition activity of HSM and HWSM was found to be approximately 1.6 times higher than the control SM and HSM The superoxide radical scavenging activity revealed to show high activity at HSM and HWSM, and no difference was found by the removal of bean-curd from raw soybean. Based upon these results, the functional characteristics of HSM, WSM and HWSM were found to be excellent compared to SM and it is expected to be used as various functional sources in a future.

Anaerobic Digestion Treatment for the Mixture of Chinese Cabbage Waste Juice and Swine Manure

  • Kafle, Gopi Krishna;Kim, Sang-Hun;Shin, Beom-Soo
    • Journal of Biosystems Engineering
    • /
    • v.37 no.1
    • /
    • pp.58-64
    • /
    • 2012
  • Purpose: The objective of this study was to investigate the feasibility of anaerobic digestion of Chinese cabbage waste juice (CCWJ) and swine manure(SM). Methods: The anaerobic digestion test was conducted under batch and continuous conditions at mesophilic temperature ($36-38^{\circ}C$). The batch test was divided into Experiment I and II. In the Experiment I, biogas potential and production rate of CCWJ was evaluated. In Experiment II the effect of F/M ratio (2.0, 3.2, 4.9) at mixture ratio of 25:75(CCWJ: SM, % vol. basis) on biogas yield was studied. Results: CCWJ produced biogas and methane yield of 929 and 700 mL/g VS added respectively. The biogas yield from the mixture of CCWJ and SM was almost same at F/M ratio of 2.0 and 3.2 but dropped by 14% when F/M ratio increased from 3.2 to 4.9. In continuous test the mixture of CCWJ and SM (25:75, % vol. basis) produced biogas yield of 352 mL/g VS added which is around 11% higher compared to biogas yield from SM alone. Addition to biogas yield digester performance was also improved with co-digestion of CCWJ with SM. Conclusions: The results showed that the anaerobic digestion of CCWJ with SM could be promising for improving both the biogas yield and digester performance at mesophilic temperature.

In vitro and in vivo Activities of SM-101, a Micture of Metampicillin and Sulbactam

  • Choi, Keum-Hwa;Kim, Sook-Kyung;Baek, Moon-Chang;Kim, Byong-Kak;Lee, Dong-Young;Choi, Eung-Chil
    • Archives of Pharmacal Research
    • /
    • v.18 no.6
    • /
    • pp.423-426
    • /
    • 1995
  • SM-101 is a mixture of metampicillin and sulbactam(2:1). The antibacterial activities of SM-101 were compared with those of metampicillin, piperacillin and Augmentin. It showed powerful antibacterial activities against major strains. Except P. anruginosa and S. marcescens, the in vitro antibacterial activity of SM-101 was higher than those of metampicillin, piperacillin and Augmentin against Staphylococcus spp., Streptococcus spp., Moganella morganii, E. Coil, and Proteus spp. The $ED_{50}$ values of SM-101 were two-fold or greater than those of metampicillin, piperacillin and Augmentin against $\beta-lactamase$ producing strains, p. mirabilis GN79 and M. morganiii MB4-11. The in vivo efficacy of SM-101 was more active than metampicillin and pipeeracillin and similar to Augmentin against S. aureus Smith, E coli MB4-01 and K. pneumoniae MB4-02.

  • PDF

Side Channel Attack on Block Cipher SM4 and Analysis of Masking-Based Countermeasure (블록 암호 SM4에 대한 부채널 공격 및 마스킹 기반 대응기법 분석)

  • Bae, Daehyeon;Nam, Seunghyun;Ha, Jaecheol
    • Journal of the Korea Institute of Information Security & Cryptology
    • /
    • v.30 no.1
    • /
    • pp.39-49
    • /
    • 2020
  • In this paper, we show that the Chinese standard block cipher SM4 is vulnerable to the side channel attacks and present a countermeasure to resist them. We firstly validate that the secret key of SM4 can be recovered by differential power analysis(DPA) and correlation power analysis(CPA) attacks. Therefore we analyze the vulnerable element caused by power attack and propose a first order masking-based countermeasure to defeat DPA and CPA attacks. Although the proposed countermeasure unfortunately is still vulnerable to the profiling power attacks such as deep learning-based multi layer perceptron(MLP), it can sufficiently overcome the non-profiling attacks such as DPA and CPA.

Fabrication of Thick SmBCO/IBAD-MgO coated conductor (후막 SmBCO/IBAD-MgO 초전도 박막선재의 제조)

  • Lee, J.H.;Kang, D.K.;Ha, H.S.;Ko, R.K.;Oh, S.S.;Kim, H.K.;Yang, J.S.;Jung, S.W.;Moon, S.H.;Youm, D.;Kim, C.J.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2009.05a
    • /
    • pp.9-9
    • /
    • 2009
  • Coated conductor is required to have good critical current property for high efficiency of electric power applications. Until now, long coated conductor does not show high Jc over 3 MA/$cm^2$ in thick superconducting layer because of texture degradation by thick superconducting layer. In this study, in order to overcome this issue, thicker superconducting layer was deposited with optimized conditions to reduce the degradation of critical current density. SmBCO superconducting coated conductor was deposited with 1~3 um of thickness at $750\sim850^{\circ}C$ under 15~20 mTorr of oxygen partial pressure using batch type EDDC( evaporation using drum in dual chamber). The buffered substrate for superconducting layer deposition was used IBAD-MgO template with the architecture of $LaMnO_3/MgO/Y_2O_3/Al_2O_3$/Hastelloy. After fabrication of coated conductor, critical current was measured by 4-prove method under self-magnetic field and 77K. In addition, surface morphology and texture were analyzed by SEM and XRD, respectively. 3 um thick SmBCO coated conductor shows highest $I_C$ values of 638A/cm-w in 1 m long in the world.

  • PDF

Magnetic properties of Mn54Al46C2.44/Sm2Fe17N3 and Mn54Al46C2.44/Fe65Co35 composites

  • Qian, Hui-Dong;Si, Ping-Zhan;Lim, Jung Tae;Kim, Jong-Woo;Park, Jihoon;Choi, Chul-Jin
    • Journal of the Korean Physical Society
    • /
    • v.73 no.11
    • /
    • pp.1703-1707
    • /
    • 2018
  • Ferromagnetic ${\tau}-phase$ $Mn_{54}Al_{46}C_{2.44}$ particles were synthesized, and its composites with commercial $Sm_2Fe_{17}N_3$ and synthesized $Fe_{65}Co_{35}$ powders were fabricated. Smaller grain size than the single domain size of the $Mn_{54}Al_{46}C_{2.44}$ without obvious grain boundaries and secondary phases is the origin for the low intrinsic coercivity. It was confirmed that the magnetic properties of the $Mn_{54}Al_{46}C_{2.44}$ can be enhanced by magnetic exchange coupling with the hard magnetic $Sm_2Fe_{17}N_3$ and soft magnetic $Fe_{65}Co_{35}$. The high degrees of the exchange coupling were verified by calculating first derivative curves. Thermo-magnetic stabilities of the composites from 100 to 400 K were measured and compared. It was demonstrated that the $Mn_{54}Al_{46}C_{2.44}$ based composites containing $Sm_2Fe_{17}N_3$ and $Fe_{65}Co_{35}$ could be promising candidates for future permanent magnetic materials with the proper control of purity, magnetic properties, etc.

Angular dependence of critical current of SmBCO coated conductor fabricated by co-evaporation method

  • Kim, Ho-Sup;Ha, Hong-Soo;Oh, Sang-Soo;Song, Kyu-Jeong;Ko, Rock-Kil;Ha, Dong-Woo;Kim, Tae-Hyung;Youm, Do-Jun;Lee, Nam-Jin;Moon, Seung-Hyun;Yoo, Sang-Im;Park, Chan
    • Progress in Superconductivity and Cryogenics
    • /
    • v.10 no.2
    • /
    • pp.16-19
    • /
    • 2008
  • Angular dependence of critical current density of SmBCO coated conductor fabricated by co-evaporation method was investigated. For comparison, three samples were fabricated by a co-evaporation method and one sample was fabricated by a pulsed laser deposition process. The deposition system, named EDDC (Evaporation using Drum in Dual Chambers), is a batch type co-evaporation system, which is composed of reaction chamber and evaporation chamber. The normalized critical current density ratio ($I_c/I_c$(H//ab-plane)) of EDDC-SmBCO samples was found to be higher than that of PLD-YBCO sample in the whole range of angle. While the EDDC-SmBCO samples evidently had a peak at the angle of H//c-axis in the plot of the angular dependence of critical current, the normalized critical current of PLD-YBCO sample decreased monotonically without any peak as angle increased. The field dependence of critical current under the magnetic field parallel to the normal direction of those samples showed similar aspect in the range of $0\;G{\sim}5000\;G$.

Conduction Characteristics of $Pr_6O_{11}$-Based ZnO Varistor Added with Samarium Oxides (사마륨 옥사이드가 첨가된 $Pr_6O_{11}$계 ZnO 바리스터의 전도특성)

  • Yoon, Han-Soo;Park, Choon-Hyun;Nahm, Choon-Woo
    • Proceedings of the KIEE Conference
    • /
    • 1999.07d
    • /
    • pp.1689-1691
    • /
    • 1999
  • The conduction characteristics of $Pr_6O_{11}$-based ZnO varistor were investigated. ZnO-$Pr_6O_{11}$-CoO-$Sm_2O_3$-based ZnO varistor were sintered at $1300^{\circ}C$ and $1350^{\circ}C$ in the addition range $0.0\sim2.0mol%$ $Sm_2O_3$, respectively. ZnO varistors which are added with 1.0mol% at each temperature exhibited best excellent conduction characteristics, namely the nonlinear exponent was 42.05 at $1300^{\circ}C$, 36.79 at $1350^{\circ}C$ and leakage current was $9.16{\mu}A$ at $1300^{\circ}C$, $11.7{\mu}A$ at $1350^{\circ}C$. Consequently, it is estimated that ZnO-$Pr_6O_{11}$-CoO-$Sm_2O_3$-based ZnO varistors, which $Sm_2O_3$ is added 1.0mol% is to be used as a basic composition of $Pr_6O_{11}$-based ZnO varistors.

  • PDF