• 대한화학회지
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• 제29권2호
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• pp.164-171
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• 1985

SAF 축합중합체와 CHBM-DVB 공중합체를 합성하였다. 이들 합성된 이온교환체의 이온교환용량은 각각, 4.6meq/g and 3.9 meq/g이었다. 또한 이들 약산성 이온교환체에 대한 몇가지 금속이온들의 흡착능과 이온교환체 성질에 대하여 논의하였다. 그리고 이온들의 염산용액중에서의 분포계수와 몇가지 용리현상에 대하여 논의하였다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 춘계학술대회논문집
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• pp.195-198
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• 2003

High temperature deformation and softening behavior of SAF 2507 super duplex stainless steel (SDSS) has been investigated in connection with an FEM analysis of hot forging process. Flow curves at various strain rates and temperatures were determined first from compression tests, and the kinetics of dynamic recrystallization were also formulated through the analysis of load relaxation test results. Applying the dynamic materials and proposed by Prasad et al., it was possible to determine the characteristics of deformation behavior effectively at a given condition of deformation. Constitutive relations and recrystallization kinetics formulated from the test results were then implemented in a commercial FEM code. Flow stress compensation formulated upon the volume fraction of recrystallization and adiabatic heating was found to improve significantly the FEA solutions in predicting the forming load and the distribution of recrystallized volume fraction after forging.

• 소성∙가공
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• 제10권3호
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• pp.206-213
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• 2001

Dynamic deformation of metallic materials mostly accompanies substantial amounts of deformation heat. Since the flow stress of deformation is sensitive to temperature, implication of heat due to plastic work is essential to the evaluation of constitutive relations. In this study, a series of compression tests were conducted for SAF 2507 super duplex stainless steel at various temperatures and strain rates. The accumulation of plastic work was calculated through numerical integration and converted into the elevation of temperature. Subsequent logarithmic interpolation deduced isothermal flow surfaces, which were primary input data of finite element analysis. Simple closed die forging process was analyzed and optimized with commercial FEM code applying both raw and calibrated material database. The effect of accounting deformation heat was more noticeable in high-speed forming process.

• 소성∙가공
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• 제12권4호
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• pp.308-313
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• 2003

High temperature deformation and softening behavior of SAF 2507 super duplex stainless steel (SDSS) has been investigated in connection with an FEM analysis of hot forging process. Flow curves at various strain rates and temperatures were determined first from compression tests, and the kinetics of dynamic recrystallization were also formulated through the analysis of load relaxation test results. Using the dynamic materials theory proposed by Prasad, the deformation behavior was effectively determined for various conditions. Constitutive relations and recrystallization kinetics formulated from the test results were then implemented in a commercial FEM code. The forming load as well as the distribution of recrystallized volume fraction after forging was successfully predicted by means of the flow stress compensation formulated upon the volume fraction of recrystallization and adiabatic heating.

• Journal of Magnetics
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• 제21권2호
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• pp.204-208
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• 2016

This paper demonstrates the key parameter detection for smelting of submerged arc furnace (SAF) based on magnetic field radiation. A magnetic field radiation model for the inner structure of SAF is established based on relative theory of electromagnetic field. A simple equipment of 3D magnetic field detection system is developed by theoretical derivation and simulation. The experiments are carried out under the environment of industrial field and AC magnetic field generated by electrode currents and molten currents in the furnace is reflected outside of the furnace. The experimental results show that the key parameters of smelting including the position of electrode tip, the length of electric arc, and the liquid level of molten bath can be achieved. The computed tomography for SAF can be realized by the detection for smelting.

• 한국자기학회지
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• 제15권6호
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• pp.315-319
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• 2005

본 연구에서는 자기터널접합(MTJs; magnetic tunnel junctions)의 스위칭 자기장($H_{SW}$)을 감소시키기 위하여 자유층으로 비정질 강자성 $Co_{70.5}Fe_{4,5}Si_{15}B_{10}$ 단일(single) 및 합성형 반강자성(SAF; synthetic antiferromagnet) 층을 사용하였다. $Si/SiO_2/Ta$ 45/Ru 9.5/IrMn 10/CoFe 7/AlOx/CoFeSiB 7 or CoFeSiB (t)/Ru 1.0/CoFeSiB (7-t)/Ru 60 (in nm) MTJs의 자기저항과 스위칭 특성을 CoFe 자유층과 NiFe 자유층을 갖는 MTJs와 비교하여 조사하였다. CoFeSiB은 포화자화($M_s$)가 $560\;emu/cm^3$으로 CoFe보다 낮고, 이방성 상수(Ku)는 $2800 erg/cm^3$으로 NiFe보다 높다. CoFeSiB SAF 구조에서 CoFeSiB 사이의 Ru 두께가 1.0 nm일 때 교환결합에너지($J_{ex}$)는 $-0.003erg/cm^2$였다. 이와 같이 비교적 작은 $J_{ex}$ 때문에, CoFeSiB SAF 자유층을 갖는 MTJs의 실험 및 Landau-Lisfschitz-Gilbert(LLG)식에 의한 시뮬레이션 결과 모두에서 $H_{SW}$가 접합크기에 의존하는 경향을 보였다. CoFeSiB SAF 자유층 MTJ의 $H_{SW}$는 CoFe, NiFe 또는 CoFeSiB single을 자유층으로 하는 MTJs에 비해 훨씬 낮게 나타났다. 따라서 CoFeSiB SAF를 자유층으로 사용한 MTJ는 micrometer에서 submicrometer 크기 영역 모두에서 보지적의 감소와 민감도 증가와 같은 우수한 스위칭 특성을 갖는 것을 확인하였다.

• 농촌의학ㆍ지역보건
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• 제15권2호
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• pp.107-111
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• 1990

A survey was undertaken to evaluate the present status of intestinal infection in army soldiers. Stool specimen of 417 soldiers fixed by SAF solution were collected from a camp located in area of Nakdong river during the period from August to October of 1990. And these stool samples were examined by formalin-ether sedimentation technique once for helminths and protozoan cysts stained with Lugol's iodine solution. The results obtained in this survey were summarized as follows : l) The overall positive rate of intestinal parasite was 18.0%. 2) The egg positive rate of intestinal helminth was 15.1%, : and 11.5% for Clonorchis sinensis. 5.0% for Metagonimus vokogawai, 1.2% for Ascaris lumbricoides 1.7% for Trichiuris trichiura. 0.2% for Taenia sp. 3) The cyst positive rate of intestinal protozoa was 4.1% ; and 1.4% for Entamoeba coli, 1.9% for Giardia lamblia 0.7% for Entamoeba histolytica, 0.5% for Endolimax nana. 4) Most of samples were positive(85.3%) by single species. 10.7% by two species, 2.7% by three species and 1.3% by four species. 5) Infection rate of intestinal parasites among army soldiers decreased distinctly compared with previous data but it is revealed that the infection rate of Clonorchis sinensis among army soldiers in area of Nakdong river is still high in comparison with ever-reported data. 6) SAF fixatives used in this field survey during summertime was useful to conserve protozoan cyst and helminths ova. Also we could examine stool samples directly by formalin-ether sedimentation technique.

• 한국광학회지
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• 제11권5호
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• pp.360-364
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• 2000

반도체 포화 흡수거울 (Semiconductor Saturable Absorber Mirror:SESAM)을 이용하여 Cr:LiSAF 레이저를 제작하고 이를 모드록킹 시켰다. 펌핑 레이저는 파장이 667 nm이고, 출력이 500mW인 두 대의 고출력 레이저(Coherent S-67-500C-100-H)가 사용되었으며, 레이저 결정은 Brewster-Brewster 모양인 $Cr^{+3}$의 농도가 1.5%이고 길이가 6mm인 것을 사용하였다. 공진기는 X-형 구조로, 곡률반경이 10cmdls 오목거울과, 군속도 보상을 위한 SF10 프리즘, 투과율이 1%의 출력거울을 사용하였다. 포화흡수체로 사용되는 SESAM의 구조는 맨위층에 10nm의 $AlAs/Al_{0.15}Ga_{0.85}As$ 양자우물과 30쌍의 $AlAs/Al_{0.15}Ga_{0.85}As/GaAs/Al_{0.15}Ga_{0.85}As$반사경으로 구성되어 있다. 펌핑 레이저의 출력이 800mWdlfEo 레이저 출력은 3mW였고, 중심파장은 833nm이었으며 스펙트럼 대역폭은 4nm, 레이저 펄스폭은 220fs 였다.

• 한국환경과학회지
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• 제19권10호
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• pp.1301-1305
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• 2010

This study was carried out to investigate the effect of KEM and SAF appication on contents change of fatty acids and organic acid of perilla(Perilla Frutescens Britton). Contenst of squalene in perilla leaves on control and KEM/SAF treated were 3.39 mg and 4.22 mg, respectively. Therefore the squalene quantity of KEM/SAF treated leaves was 24.2% more than that of control. A total 6 fatty acids in perilla leaves were analyzed in this study. Percentage of the saturated and unsaturated fatty acid in perilla leaves were 20 and 80%, respectively. Contents of phytosterols in perilla leaf such as campesterol and sitosterol were 2.0 and 20.0 mg, respectively. Therefore sitosterol content was 10 fold more than that of campesterol. The KEM/SAF application on perilla leaf was effective on the change of squalene or phytosterol contents. However effect of that was negligible on the change of fatty acid content.

• 한국환경과학회지
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• 제19권10호
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• pp.1293-1299
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• 2010

This study was carried out to compare and analyze the effect of Korean effective microorganism(KEM) and seafood amino acid fertilizer(SAF) application on apple on functional substances of fruit. Vitamin C in fruit of control and KEM/SAF treated were 29.3 and, 39.8 mg, respectively. Also active oxygen scavenging ability of those treatments measured with DPPH method were 40.6 and 54.1%, respectively. Vitamin E contents of those treatments were 2.51 and 2.50 mg, respectively. Sitosterol, a phytosterol, contents of those treatments were 4.79 and 5.41 mg, respectively. Proportion of sugars, fructose, glucose, and sucrose in the fruit of control were 36.1, 15.3 and 17.8%, respectively. Those of the fruit of KEM/SAF treated were 45.9, 13.2 and 18.8%, respectively. Malic acid contents of control and KEM/SAF treated fruits were 53.7 and 43.8%, respectively.