• Title/Summary/Keyword: compositional change

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신안동전성분분석에 관한 연구(I)

  • Lee, Chang-Keun;Kang, Dae-III;Hwang, Chae-Geum
    • 보존과학연구
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    • s.6
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    • pp.121-196
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    • 1985
  • Atomic absorption spectrophotometer was used for analyzing each 10elements(Cu, Pb, Sn, Zn, Sb, Fe, Ni, Ag, Co and Mn)on 64 Chinese coinsre covered from Shinan seabed sunken ship. The results show that Cu, Pb and Sn were found to be a major elements consisting of coins and its composition ratio was 6 to 2 to 1.The composition of trace elements on coins was classified 3 levels : Sb, Fe and Zn(0.02%-2.2%), Ag, Ni, and Co(50 ppm-5500 ppm) and Mn(Trace). Theam ount of major elements, Cu and Sn were decreased while increased in Pbby the passage of ages (10th - 13th century) in China. There seems to be no systematic compositional change in major elements but content in trace elements was confirmed to increase with age.

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A Case Report on the Juvenile Scoliosis and Obesity Treated by Chuna Therapy (추나요법을 시행한 소아의 측만증과 비만도를 개선시킨 1례)

  • Cho, Woong-Hee;Park, Won-Hyung;Cha, Yun-Yeop;Ji, Hyun-Chul
    • Journal of Korean Medicine for Obesity Research
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    • v.9 no.2
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    • pp.75-82
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    • 2009
  • Objective This study is designed to evaluate the effectiveness of Chuna Therapy for the patient with juvenile scoliosis. Methods The first X-ray examination was performed at the first visit suffering from disproportion, and the second performed after therapy. The first image was compared with second one. And We checked body composition using Inbody3.0 before and after Chuna Therapy. Result & Conclusions The second x-ray shows clearly improvement of scoliosis compared with previous x-ray. And, we obtained that the result of body compositional change.

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Segregation Mechanism in Si1-xGex Single Crystal Fiber Growth by Micro-pulling Down Method

  • Uda, Satoshi;Kon, Junichi;Shimamura, Kiyoshi;Fukuda, Tsuguo
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1996.06a
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    • pp.399-421
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    • 1996
  • (1) The solute distribution mechanism was analyzed for the Si0.95Ge0.05 single crystal fiber by u-PD method. (2) The steady-state solutions were obtained for the molten zone and the capillary zone. (3) The effect of the convection in the molten zone on partitioning was not significant for many cases. (4) Intermediate transient rise of Ge was shown by the sudden change of the growth velocity or molten zone height. (5) Periodic compositional modulation can be designed by using the intermediate transient.

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Shear Induced Homogenization Study of an Immiscible Polymer Blend Solution Using Fluorescence Microscope (형광 현미경을 이용한 비상용 고분자 블렌드 용액의 전단 균질화 연구)

  • 유재웅
    • Polymer(Korea)
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    • v.27 no.5
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    • pp.413-420
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    • 2003
  • Fluorescence microscope technique was employed for the characterization of phase separation behavior of a 4-chloro-7-nitrobenzofurazan labeled polystyrene (PS) / polybutadiene (PB) blend in dioctyl phthalate under steady shear. It was confirmed that the fluorescence microscope images reflect the real phase morphology by comparing with the images of phase contrast microscope. Comparing the fluorescence intensities from the phase separated domain (PS rich) and continuous phase (PB rich), the composition difference between these two phases were deduced. The observed shear dependence of compositional change is then used to confirm that the phase diagram is indeed shifted under the steady shear.

The Characteristics of the Chungja Celadon the Amount of BaTio3 (BaTio3 조성비 변화에 따른 청자소지물질의 특성)

  • Yun, Mi-Young;Kim, Yeon-Jung;Ja, Lim-Hun
    • Journal of the Korean institute of surface engineering
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    • v.45 no.1
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    • pp.31-36
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    • 2012
  • In order to improve the mechanical roperties of the Gangjin celadon $BaTiO_3$ was added into the raw materials of celadon matrix. Through SEM and XRD analysis the structural changes were observed and the hardness values were measured. We could confirm that the mechanical strength considerably increased in the $BaTiO_3$ added celadon through the measurement of hardness values. The increase of mechanical strength values in the celadon may result from the compositional change in the microstructure such as grain boundary area through EDAX analysis. We might suggest a fundamental idea to improve the mechanical intensity of the celadon.

Compositional Effects on Thermal and Electrical Properties of Dielectric Glass Paste

  • Kim, Teock-Nam;Lee, Jea-Yeol;Kim, Hyung-Sun;Hu, Jeung-Soo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2000.01a
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    • pp.95-96
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    • 2000
  • The effect of $Al_2O_3$ on the dielectric constant and the coefficient of thermal expansion of lead borosilicate glasses for the application of PDP glass paste was investigated. Measurements were made theoretically by using empirical equations on the composition of the of glasses in which the $PbO/Al_2O_3$, $B_2O_3/Al_2O_3$ and $SiO_2/Al_2O_3$ ratios were systematically varied. As a result, with increasing $PbO/Al_2O_3$ the thermal expansion coefficient and the dielectric constant noticeably increased, while the change of $B_2O_3/Al_2O_3$ and $SiO_2/Al_2O_3$ ratios did not affect those properties of the glasses.

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Study on Synthesis and Characterization of (Ti.Si)C Composite by SHS Microwave (SHS 마이크로파에 의한 (Ti.Si)C 복합체의 합성 및 소결특성에 관한 연구)

  • 이형복;권상호;이재원;안주삼
    • Journal of the Korean Ceramic Society
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    • v.32 no.9
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    • pp.1009-1018
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    • 1995
  • (Ti.Si)C composite powders were synthesized by SHS method using microwave energy. Compositional and structural characterization of the powder were carried out by using scanning electron microscopy and X-ray diffraction. The average particle size of the synthesized (Ti.Si)C composite powders was smaller than that of the starting materials. From the results of the temperature profile, combustion temperature and velocity were decreased with increasing Si molar ratio. With increasing C molar ratio combustion temperature and velocity did not change. (Ti.Si)C composite was sintered at 185$0^{\circ}C$ for 60 min by using hot-pressing with 30 MPa. The best properties were obtained from the sintered specimen whose composition was 1 : 1 : 1.9 molar ratio of Ti : Si : C. The sintering density, flexural strength and vickers hardness of the sintered body were 4.71 g/㎤, 423 MPa and 21 GPa, respectively.

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Examination of Ingredients of High Temperature Heat Resistant Inorganic Fire-Resistant Adhesive Using XRD Analysis (XRD 분석을 이용한 고온가열 무기계 내화 접착제의 성분검토)

  • Cho, Hyeon-Seo;Ji, Woo-Ram;Shin, Ki-Don;Lee, Gun-Cheol
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2018.11a
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    • pp.81-82
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    • 2018
  • The structure of the RC structure is actively reinforcing the structure of the building which has suffered from aging, artificial and natural damage of the building. Among various reinforcement methods, epoxy adhesive is used to attach FRP in FRP reinforcement method which is reinforcing by attaching FRP to the structural part. At this time, the epoxy adhesive having a low critical temperature has a sudden adhesive failure upon exposure to heat, and thus, the development of an inorganic fireproof adhesive having a high critical temperature has progressed. Therefore, in this study, the compositional change of inorganic fire - resistant adhesive exposed to high temperature heat was analyzed by XRD.

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Knowledge-Based Dynamic Structuring of Process Control Systems

  • de Silba, Clarence W.
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1993.06a
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    • pp.1137-1140
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    • 1993
  • A dynamic-structure system is one that has the flexibility to change the system configuration automatically so as to operate in an optimal manner. A conceptural model for a dynamic-structure system is presented in this paper. In this model, the interchangeable components of the overall system are grouped together. Their activity levels are evaluated by an intelligent preprocessor that is associated with the group. A knowledge-based task distribution system evaluates the activity levels and makes decisions as to how the components operating below capacity should be shared with workcells that have similar components that are overloaded. Associated decision making can be effected through fuzzy logic and particularly the compositional rule of inference. A simulation example is given to illustrate the application of dynamic structuring.

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The change of magnetic microstructure with Co-22%Cr film thicknesses (Co-22%Cr 자성합금박막에서 박막두계에 따른 자기미세구조 변화)

  • 송오성
    • Journal of the Korean institute of surface engineering
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    • v.31 no.5
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    • pp.261-265
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    • 1998
  • We investigated compositional separation of Co-23%Cr magnetic alloy thin films with varying film thicknesses. Saturation magnetization and magnetic microstructures were investigated using vibrating sample magnetometer (VSM) and scanning probe microscope (SPM), respectively. Saturation magnetization was as 700 emu/cc for films below 50 nm-thick, and changed to 430 emu/cc for the ones above 2000 nm-thick. This may be due to increment of molar volume of Cr-enriched phase as film thickness increases. The surface grain size in AFM (atomic force microscope) measurement becomes larger as film thickness increases. The MFM (magnetic force microscope) reveals that magnetic microstructure is changed from the fine spherical domains to the maze type domains as film thickness increases. We conclude that employing thickness of Co-22%Cr films below 50 nm is favorable for high density recording in order to enhance perpendicular saturation magnetization and SNR (signal to noise ratio).

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