• Proceedings of the Materials Research Society of Korea Conference
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• 한국재료학회 1998년도 IUMRS-ICEM ABSTRACT BOOK
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• pp.48.4-48
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• 1998

• Journal of the Korean Magnetics Society
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• 제5권5호
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• pp.767-771
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• 1995

The atomic structure and magnetic properties of $LaCo_{13}$ amorphous alloy have been investigated and compared with those of its crystalline counterpart. It has been confirmed that the amorphous alloy is composed of the icosahedral clusters with a $NaZn_{13}$-type structure. The magnetic moment and the spin- wave stiffness constant obtained from the magnetic measurements in the amorphous state are larger than those in the crystalline state. The Curie temperature estimated from the reduced magnetization curve for the former is much higher than the value for the latter. The localized magnetic moment character in the amorphous state is stronger than that in the crystalline state.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.34-35
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• 2006

The development of Micro MIM as a new manufacturing process for metallic micro parts made of advanced functional materials has been the subject of considerable research over the last years. This paper addresses important quality aspects on processing of new materials by Micro-MIM. Three examples of new functional materials that can be processed are reviewed in this paper. The first example is two-component-Micro-MIM to obtain multi-functional devices. A micro positioning encoder consisting of a magnetic / non-magnetic material combination is presented. The second issue is series production of the replicate of the smallest human bone in the ear (stapes) from Titanium as an example of medical application. Quality assurance and reproducibility in terms of injection moulding parameters are addressed. In the third part, first results on the processing of the shape memory alloy NiTi by Micro-MIM are presented. Potential applications include biocompatible devices and transportation, for example automotive and aerospace. Processing routes and initial microstructures obtained are discussed.

• Transactions on Electrical and Electronic Materials
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• 제5권1호
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• pp.29-33
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• 2004

The materials showing high structure dispersity have been developed on the quartz base by mechano-chemical technology. Depending on the processing conditions and subsequent applications, the materials produced by mechano-chemical reaction (MCR) showed concurrently magnetic, dielectric and electrical properties. The obtained magnetic-electrical powders classified by aggregate complex of their features as segneto-magnetics, contained a dielectric material as a carrying nucleus, particularly the quartz on that surface one or more layers of different compounds was synthesized having thickness up to 10∼50 nm and showing magnetic properties and etc.

• Journal of the Speleological Society of Korea
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• 제78호
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• pp.9-15
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• 2007

The materials showing high structure dispersion with functional properties were developed on the quartz base and those were obtained by mechano-chemical reaction technology. Depending on the processing conditions and subsequent applications the materials produced by mechano-chemical reaction show concurrently magnetic, dielectric and electrical properties. The obtained magnetic-electrical powders classified by aggregate complex of their features as segnetomagnetics, containing a dielectric material as a carrying nucleus, particularly the quartz on that surface one or more layers of different compounds were synthesized having thickness up to 1050nm showing magnetic, electrical properties and others. The similarity of the structure of surface layers of quartz particles subjected to mechano-chemical processing and nano-structure cluspol (clusters in a polymer matrics) material was alsoconfirmed by the fact that the characteristics of ferromagnetic quartz of insulating nano-composite powder were changed with time, after its preparing process was completed.

• Proceedings of the Materials Research Society of Korea Conference
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• 한국재료학회 2002년도 추계학술발표강연 및 논문개요집
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• pp.134-134
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• 2002

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.585-587
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• 2002

The materials showing high structure dispersity are developed on the quartz base and they are obtained by mechano-chemical technology. Depending on the processing conditions and subsequent applications the materials produced by mechano-chemical reaction show concurrently magnetic, dielectric and electrical properties. The obtained magnetic-electrical powders classified by aggregate complex of their features as segnetomagnetics, contain a dielectric material as a canγing nucleus, particularly the quartz on that surface one or more layers of different compounds are synthesized having thickness up to 10~50 nm and showing magnetic, electrical and other properties.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.866-867
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• 2006

This work will report a highly textured ${\beta}-Si_3N_4$ ceramic by aqueous slip casting in a magnetic field and subsequent pressureless sintering, Effects of the sintering aids, polymer dispersant, pH and stirring time on the stability of the $Si_3N_4$ slurries were studied. The textured ${\beta}-Si_3N_4$ with 97 % relative density could be obtained by slip casting in a magnetic field of 12 T and subsequent sintering at $1800^{\circ}C$ for 1 h. The textured microstructure is featured by the alignment of c-axis of ${\beta}-Si_3N_4$ crystals perpendicular to the magnetic field, and the Lotgering orientation factor, f, is determined to be 0.8.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.846-848
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• 2002

A large-area (830mm ${\times}$ 1,020mm) inductively coupled plasma source with a six internal straight antennas was developed for large area FPD etch process applications and the effects of magnetic fields employing permanent magnets on the plasma characteristics were investigated. By employing the magnetic fields perpendicular to the six straight antenna currents using permanent magnets, improved plasma characteristics such as increase of the ion density and decrease of both electron temperature and plasma potential could be achieved in addition to the stability of the plasma possibly due to the reduction of the electron loss. However, the application of the magnetic field decreased the plasma uniformity slightly even though the uniformity within 10% could be maintained in the 800mm processing area.

• Journal of Magnetics
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• 제18권3호
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• pp.311-316
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• 2013

Digital image processing has increasingly been implemented in nanostructural analysis and would be an ideal tool to characterize the morphology and position of self-assembled magnetic nanoparticles for high density recording. In this work, magnetic nanoparticles were synthesized by the modified polyol process using $Fe(acac)_3$ and $Pt(acac)_2$ as starting materials. Transmission electron microscope (TEM) images of as-synthesized products were inspected using an image processing procedure. Grayscale images ($800{\times}800$ pixels, 72 dot per inch) were converted to binary images by using Otsu's thresholding. Each particle was then detected by using the closing algorithm with disk structuring elements of 2 pixels, the Canny edge detection, and edge linking algorithm. Their centroid, diameter and area were subsequently evaluated. The degree of polydispersity of magnetic nanoparticles can then be compared using the size distribution from this image processing procedure.