• Corrosion Science and Technology
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• 제4권1호
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• pp.33-38
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• 2005

Some feasibility studies are conducted to produce an advanced ceramic coating, which reveals superior chemical and mechanical strength, on metal base structure used in chemical plant. This advanced coating on metallic frame can replace ceramic delivery pipe and reaction chamber used in chemical plant, which are operated in hi-temperature and corrosive/erosive environment. An dual spraying is adopted to reduce the residual stress in order to increase the coating thickness and the residual stress is estimated by in-situ manner. Then new methodology is tried to form special coating of yttrium aluminum garnet(YAG), which reveals hi-strength and low-creep rates at hi-temperature, superior anti-corrosion property, hi-stability against Alkali-Vapor corrosion, and so on, on iron base structure. To verify the formation of YAG during thermal spraying, XRD(X ray diffraction) technique was used.

• Journal of Magnetics
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• 제2권2호
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• pp.42-45
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• 1997

The microscopic physical properties of nonstoichiometric garnet EuxFe2-xO3 (x=0.8 and 0.7) have been studied by the methods of X-ray diffraction at room temperature and M ssbauer spectroscopy within the temeperature range of 12-560 K. The X-ray diffraction patterns of the samples show coexistence of dominant garnet and a small portion of unknown crystal phase. But the M ssbauer spectra for the sample of EF08 and EF07 near N el temperature determined to be equally 549$\pm$5K show that there are no any other extra crystal phases within the experimental error. The results of which the temperature dependence of M ssbauer parameters was anlyzed by the spin-wave theory and Debye model are in good agreement with the fact that the sample of EF08 has some vacancies at a-and/or d-sites.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2002년도 동계연구발표회 논문개요집
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• pp.108-109
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• 2002

자성 garnet(YIG)의 현재 가장 널리 쓰이는 microwave 자성재료 중 하나이며 자기적 손실이 적은 특성을 가지고 있다고 보고되어 지고 있다.[1] Microwave 소자로 응용하기 위해서는 포화자화값 (M$_{s}$ ), 보자력 (H$_{c}$), Neel 온도 (T$_{N}$)등을 제어하는 기술을 요구되어진다. 이러한 자성재료인 Garnet의 결정 내에는 octahedral-16a과 tetrahedral-24d 그리고 dodechahedral-24c의 세 개의 부격자가 있다. 이러한 부격자들에 치환되는 이온에 따라 자기적 교환 상호작용이 달라지게 된다. (중략)

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1998년도 PROCEEDINGS OF THE 15TH KACG TECHNICAL MEETING-PACIFIC RIM 3 SATELLITE SYMPOSIUM SESSION 4, HOTEL HYUNDAI, KYONGJU, SEPTEMBER 20-23, 1998
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• pp.53-53
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• 1998

Four valence of Chromium ion doped Yttrium Aluminum Garnet crystals were grown by Floating Zone and Czochralski methods. Changes of valence for Chromium (3+) ion to Chromium (4+) were achieved by substitution of Yttrium ion in dodecahedral site to Calcium and by substitution of Aluminum in octahedral site to Magnesium. Growth conditions for high quality of crystals were investigated. Grown crystals were cut and polished and then observed various types of defects. Characterizations by means of measurement of density and lattice parameter as a function of solidification fraction were performed. Results of Q-switching test using grown crystals were also reported.

• 한국전기전자재료학회논문지
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• 제20권6호
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• pp.536-540
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• 2007

The Ce-doped YAG(Yttrium Aluminum Garnet, $Y_3Al_5O_{12}$) phosphor powders were synthesized by combustion method. The luminescence, formation process and structure of phosphor powders were investigated by means of XRD, SEM and PL. The XRD patterns show that YAG Phase can form through sintering at $1000^{\circ}C$ for 2 h. This temperature is much lower than that required to synthesize YAG phase via the conventional solid state reaction method. There were no intermediate Phases such as YAP(Yttrium Aluminum Perovskite, $YAlO_3$) and YAM(Yttrium Aluminum Monoclinic, $Y_4Al_2sO_9$) observed in the sintering process. The powders absorbed excitation energy in the range $410{\sim}510\;nm$. Also, the crystalline YAG:Ce showed broad emission peaks in the range $480{\sim}600\;nm$ and had maximum intensity at 528 nm.

• 한국자기학회지
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• 제5권5호
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• pp.720-725
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• 1995

Bi-substituted gadolinium iron garnet films were deposited on GGG(111) and NGG (111) substrates by irradiating KrF excimer laser onto targets having compositions of $Bi_{x}Gd_{3-x}Fe_{5}O_{12}$ ($2.0{\leq}x{\leq}3.0$) under substrate temperature of $580~620^{\circ}C$. Analysis on structure, composition and angle of Faraday rotation, ${\theta}_{F}$, were carried out. The composition, the structure and the magneto-optical properties of the obtained films were found to be strongly dependent both on the compositions of the targets and on the pressure of oxygen. Before annealing in air, all films showed ${\theta}_{F}{\geq}0$ at ${\lambda}=6328{\AA}$, while several films showed ${\theta}_{F}{\leq}0$ after the annealing. The highest value of Bi-substitution up to x = 1.76 with uniform composition was obtained.

• Medical Lasers
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• 제9권1호
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• pp.76-78
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• 2020

Verruca plana is a cutaneous infection caused by the human papilloma virus. Although various treatment methods are currently available, most have limitations due to the risk of complications such as hyperpigmentation, edema, and scarring. Moreover, as the infection tends to spread easily, new verrucae can potentially develop, and treatment procedure times tend to be lengthy. Thus, novel treatment methods are required. The 2790-nm wavelength erbium:yttrium-scandium-gallium-garnet (Er:YSGG) laser is a superficial resurfacing laser. Here, we present a case of a 25-year-old woman with multiple verrucae treated using a 2790-nm Er:YSGG laser. Compared to traditional methods, this novel laser is convenient, produces better cosmetic outcomes, and is less time-consuming; it is therefore suitable for the treatment of facial verruca plana.

• Medical Lasers
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• 제9권1호
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• pp.84-87
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• 2020

Post-acne erythema (PAE) is one of the major problems during or after treatment of acne vulgaris with any modality. A variety of therapeutic options have been described with various clinical outcomes and side effects. We report here on treating a patient with PAE using 595-nm picosecond-domain neodymium:yttrium-aluminum-garnet (Nd:YAG) laser. After four sessions of treatment, the patient displayed nearly complete improvement and no remarkable adverse effects. To the best of the authors' knowledge, this is the first case of the effective treatment of PAE using a 595-nm picosecond-domain Nd:YAG laser. We recommend that using a 595-nm picosecond-domain Nd:YAG laser can be both an effective and safe treatment option for treating PAE.

• Medical Lasers
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• 제10권4호
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• pp.242-245
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• 2021

Acne vulgaris is a common inflammatory skin disease of the pilose-baceous unit. It appears as lesions consisting of comedones, papules, pustules, and nodules of varying shapes and severity. In general, the first-line treatment for acne vulgaris includes topical and oral medication. Recently, various physical modalities have also been investigated. The use of laser therapy is steadily increasing because of its fewer side effects, short procedure time, and rapid results. In particular, laser therapy assisted with carbon suspension application is effective for acne vulgaris but may sometimes result in discomfort due to odor and dust formation during the procedure. Herein, we report that acne vulgaris and enlarged facial pores can be safely and effectively treated with laser therapy assisted with diamond particle suspension and gold microparticle application, which can address the discomfort caused by the carbon suspension application.

• 한국지구과학회지
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• 제44권4호
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• pp.307-317
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• 2023

We investigate the provenance of detrital garnets in Middle-Upper Jurassic sandstone of the Mino terrane, an accretionary complex in Southwest Japan, based on their chemical composition. The garnet grains in the Mino sandstone are mostly Fe-rich (almandine) and slightly Mg-rich (pyrope) species derived from high-grade metamorphic and intermediate to acidic plutonic rocks. The composition and interpreted origin of the garnets are generally consistent with those of metamorphic and igneous rocks of the Yeongnam Massif on the Korean Peninsula, a possible source region suggested in previous studies. In addition, two single grains of chromian spinel, an accessory mineral found in mafic to ultramafic rocks such as mantle peridotite, were found in one of the Mino sandstone samples. This finding suggests the possible presence of mafic to ultramafic rocks in the source area. The results of this study provide complimentary evidence for establishing a comprehensive tectonic and paleogeographical framework for the Mesozoic East Asian continent.