• 한국재료학회:학술대회논문집
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• 한국재료학회 1996년도 재료학회 추계학술발표회
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• pp.174-176
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• 1996

In the YBCO matrix, 10wt.% Y$_2$BaCuO$\_$5/ (211 phase) was added, the final 211 content of YBCO made by MTG process could reach about 20wt.% which was the optimum value for the critical current density. And also 10wt.% Ag was added in the matrix of YBCO, which was nearly about the saturate solubility of silver in textured YBCO. SmBaCuO crystal was grown by the melted-condensed process. A 5${\times}$5${\times}$2㎣ single crystal of SmBaCuO was used to be the seed in the preparation of YBCO. It was proved the orientation of YBCO was the same as the orientation of the SmBaCuO seed. The oxygen absorption of bulk oriented YBCO was studied and the heat treatment of oxygen absorption would be in flowing oxygen, at 400$^{\circ}C$ for about 24 hours. the magnetic hysteresis loops were measured by Vibrating Smaple Magnetometer and the J$\_$c/ was calcuated by means of Bean's model.

• Bulletin of the Korean Chemical Society
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• 제34권11호
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• pp.3451-3455
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• 2013

Single-crystalline silicon nanowires (SiNWs) were fabricated by using an electroless metal-assisted etching of bulk silicon wafers with silver nanoparticles obtained by wet electroless deposition. The etching of SiNWs is based on sequential treatment in aqueous solutions of silver nitrate followed by hydrofluoric acid and hydrogen peroxide. SEM observation shows that well-aligned nanowire arrays perpendicular to the surface of the Si substrate were produced. Free-standing SiNWs were then obtained using ultrasono-method in toluene. Alkyl-derivatized SiNWs were prepared to prevent the aggregation of SiNWs and obtained from the reaction of SiNWs and dodecene via hydrosilylation. Optical characterizations of SiNWs were achieved by FT-IR spectroscopy and indicated that the surface of SiNWs is terminated with hydrogen for fresh SiNWs and with dodecyl group for dodecyl-derivatized SiNWs, respectively. The main structures of dodecyl-derivatized SiNWs are wires and rods and their thicknesses of rods and wire are typically 150-250 and 10-20 nm, respectively. The morphology and chemical state of dodecyl-derivatized SiNWs are characterized by scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy.

• 한국환경보건학회지
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• 제31권2호
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• pp.172-178
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• 2005

A laboratory experiment was performed to investigate simultaneous removal of phosphorus and nitrogen from raw sewage by intermittently aerated activated sludge process packed with aluminum and silver plate. Two continuous experimental process, i.e. an intermittently aerated activated sludge process, and an intermittently aerated activated sludge process with an aluminum and silver plate packed into the reactor were compared. The pitting corrosion of aluminum does not affect the performance of the biological treatment. The amounts of Al eluted from aluminum plate 17 mg to 60.6 mg in this experimental conditions, and Al/P mole ratio were from 3.31 to 11.25. The total nitrogen removal efficiency in Run E were $60.6\%$ at the HRT of 12 hours. The effluent $PO_4-P$ concentration as low as $1.0\;mg/\iota$ could have been obtained during the continuous experiment in Run E at HRT of 12 hours.

• Bulletin of the Korean Chemical Society
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• 제20권5호
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• pp.581-586
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• 1999

A series of polyethers containing the thiazole or oxazole subcyclic moiety have been synthesized. Reaction of 2-aryl-4-hydroxymethylthiazole with tetra- and pentaethylene glycol di-p-tosylate in THF provided corresponding α,ω-bis[2'-aryl-4'-methylthiazole]polyethylene glycol in good yields. Similar treatment of 2-phenyl-4-hydroxymethyloxazole 7 and 2-phenyl-5-hydroxymethyloxazole 8 with tetraethylene glycol di-p-tosylate yielded the corresponding 1,13-bis [2'-phenyl-4'-methyloxazole]tetraethylene glycol 16 and 1,13-bis[2'-phenyl-5'-methyloxazole]tetraethylene glycol 17 in 69 and 43% yields in respectively. The potentiometric properties of PVC-based ion selective membranes containing 66 wt% o-nitrophenyloctyl ether (NPOE) and 4 wt% polyethers 9-17 have been examined. The membranes containing thiazole and oxazole polyether derivatives exhibited high selectivity toward silver (I) ion. It was observed that the response slopes of the electrodes to silver ion vary with the length of polyether chain linking two thiazole subcyclic moiety. Potentiometric data suggest that the number of ether units, CH2OCH2, for phenylthiazole derivatives be greater than 5 to result in near-Nernstian response. However, the response behaviors of the membrane electrodes based on phenyloxazole podands 16 and 17, which have different orientation, were correspondingly similar to those of the electrodes based on phenylthiazole podands 9 and 10. On the other hand, the ISEs based on thiazole polyether derivatives with different terminal substituents, e.g., phenyl 10, naphtyl 14, and thienyl 15, except that with pyridyl 12, exhibited little difference in their potentiometric properties.

• Nano
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• 제13권12호
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• pp.1850145.1-1850145.8
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• 2018

In this study, a double-solvent radiation method is proposed to prepare silver nanoparticles in the pores of metal-organic framework MIL-101(Cr). The results reveal that well-dispersed silver nanoparticles with a diameter of about 2 nm were successfully fabricated in the cages of monodisperse octahedral MIL-101(Cr) with a particle size of about 400 nm. The structure of MIL-101(Cr) was not destroyed during the chemical treatment and irradiation. The resulting Ag/MIL-101 exhibits excellent catalytic performance for the reduction of 4-nitrophenol. This method can be extended to prepare other single or bimetallic components inside porous materials.

• 한국작물학회지
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• 제49권5호
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• pp.363-367
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• 2004

The deep irrigation of rice plants brings about some beneficial effects such as reduced tiller production which results in the formation of bigger panicles, prevention of chilling injury, reduced weed growth, etc. The present study was carried out to examine the involvement of ethylene in the suppression of tiller production due to deep water irrigation in rice (cv. Dongjinbyeo). The ethylene production was induced in leaf sheath within 24 hours after the deep water irrigation and has increased even until 30 days after the treatment, recording 4.5-fold increase as compared to the shallow-irrigated rice plants. In the deep water irrigated rice plants, ethylene was accumulated to a high concentration in the air space of submerged leaf sheath as the irrigated water deterred the diffusion of ethylene out of the leaf sheath and ethylene biosynthesis was accelerated by the deep irrigation as well. The ethylene concentration recorded 35-fold increase in the deep-irrigated rice plants for 35 days. The tiller production was reduced significantly by the deep irrigation with water, the tiller bud, especially tertiary tiller bud differentiation being suppressed by the deepwater irrigation treatment, whereas the rice plants deep-irrigated with solutions containing $10^{-5}$ M or $10^{-6}$ M silver thiosulfate (STS), an action inhibitor of ethylene, showed the same or even higher production of tillers than those irrigated shallowly with water. This implies that the ethylene is closely linked with the suppression of tiller production due to deep water irrigation. In conclusion, ethylene, which was induced by hypoxic stress and accumulated in the leaf sheath due to submergence, played a key role in suppressing the tiller production of the deepwater irrigated rice.

• 대한수의학회지
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• 제42권2호
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• pp.253-260
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• 2002

Fowl red mite, Dermanyssus gallinae, is the most important ectoparasite affecting egg layers worldwide. More than 35 compounds have been used for fowl red mite control. Although some of them are efficient, several compounds are unsuitable in terms of food safety and environmental problems. Some compounds are efficient in theory but inadequate in practice. It is also expensive in material and labor to control effectively. Effective doses are very close to toxic doses and repeated treatment is required. Repeated, long term treatment of compounds on fowl red mite populations, may cause heritable resistance against the mites. In this study, antigenicity of fowl red mite and house dust mite, Dermatophagoides pteronyssinus, were identified by SDS-PAGE, silver staining, Western blotting and ELISA to investigate immune effects against fowl red mite using somatic antigens of fowl red mite and house dust mite. By SDS-PAGE, silver staining and Western blotting, several common antigens (110, 60, 56, 49, 46 kDa) of both fowl red mite and house dust mite were recognized. To identify immune effect of somatic antigens of fowl red mite and house dust mite, sixty white leghorn broilers(1 week old) were used. Among sixty white leghorn broilers, twenty were immunized with fowl red mite somatic antigens(Group I), twenty immunized with house dust mite antigens(Group II), and twenty were control group without antigen(Group III), respectively. After immunization, it was identified that antibody titers were increased both in group and II. Then all groups were challenged with fowl red mites. After 2 months, measurements of body weights, packed cell volume(PCV), ELISA OD values and numbers of mites were significant(p<0.05). These results suggest that fowl red mite and house dust mite, which are easy to collect and maintain, can be good vaccine candidates against fowl red mite in chicken.

• 박물관보존과학
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• 제12권
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• pp.59-69
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• 2011

황남대총 출토 용문투조은판피안교의 보존처리 과정과 제작기법에 대해 소개하고자 한다. 보존처리는 물리적, 화학적 방법을 병행하여 이물질제거를 실시하였으며, 강화처리와 함께 결실 및 취약한 부분은 접합·복원하였다. 안교금구와 좌목선금구 분석결과 은(Ag)이 99 wt%이상이며, 원두정, 내연금구, 복륜은 구리 위에 수은아말감 금도금기법으로 제작하였다. 은판으로 투조된 안교금구와 좌목선금구의 결합방법은 두금구를 포갠 후 내연금구를 올려 놓고 금동원두정을 일정 간격으로 박아 결합시켰다. 그리고 곡선 형태로 생장한 나무를 의도적으로 목심으로 사용하였으며, 마(麻), 모(毛) 종류의 평직직물이 부착되어 제작되었음을 확인하였다.

• 열처리공학회지
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• 제24권5호
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• pp.243-250
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• 2011

When alloys are vacuum-deposited on cooled substrates, super-rapidly cooled alloy films in the unequilibrium state can be obtained. As an application of this method, Ag-Cu, Ag-Ni and Ag-C alloys were successfully produced, and their mechanical properties with tempering temperature were investigated. The following results were obtained : (1) In case of Ag-Cu alloys, the solid solution was hardened by tempering at $150^{\circ}C$. The hardening is considered to occur when the solid solution begins to decompose into ${\alpha}$ and ${\beta}$ phases. The Knoop hardness number of a 40 at.%Ag-Cu alloy film deposited on a cooled glass substrate was 390 $kg/mm^2$. The as-deposited films were generally very hard but fractured under stresses below their elastic limits. (2) In case of Ag-Ni and Ag-C alloys, after the tempering of 4 at.%Ni-Ag alloy at $400^{\circ}C$ and of 1 and 2 at.%C-Ag alloys at $200^{\circ}C$, they were hardened by the precipitation of fine nickel and carbon particles. The linear relationship between proof stress vs. $(grain\;diameter)^{-l/2}$ for bulk silver polycrystals can be applied to vacuum-deposited films up to about 0.1 ${\mu}m$ grain diameter, but the proof stress of ultra-fine grained silver with grain diameters of less than 0.1 ${\mu}m$ was smaller than the value expected from the Petch's relation.

• 창의정보문화연구
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• 제6권3호
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• pp.129-139
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• 2020

19세기 이후 다양한 분야의 과학기술이 거듭 성장하면서 의료분야에서도 보다 혁신적인 기술들이 높은 수준에까지 발전하고 있다. 융복합 기술의 촉진으로 인하여 실버계층을 위한 환자만족도 증진 시스템이 국내 메디컬 프로세스에 도입되고 있지만 기존 대형병원을 중심으로 한정적인 운용성을 유지하고 있으며, 서비스 시스템의 환경 여건 및 높은 경제적 비용으로 인하여 중소병원에서의 활용이 불가피한 실정이다. 그로인해 환자 만족도의 취약성 및 실버계층에 대한 서비스 접근성이 낮아지는 현상이 발생하게 된다. 본 논문에서는 HTK(Hidden Markov Model Toolkit)를 이용하여 일반 사용자는 물론 실버 계층과 같은 취약 계층까지 메디컬 서비스에 대한 사용자 접근성을 높일 수 있도록 하고 중소병원에서의 효율적인 환자 만족 서비스 관리가 가능하도록 하는 안드로이드 기반의 저비용 스마트 진료 정보서비스 시스템(Smart Medical treatment Information Service System)설계 기법을 제안한다.