• 대한치과보철학회지
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• 제34권3호
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• pp.438-447
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• 1996

This study was performed to determine the failure strength and pattern of implant prosthesis luted with resin cement between gold cylinder and superstructure, and to evaluate the bonding strength of resin cement. To evaluate failure strength and pattern, the groups were divided into 2. Group 1 : Casted gold cylinder Group 2 : Luted with resin cement between gold cylinder ans superstructure. To evaluate effects of the bonding strength of the implant prosthesis luted with resin cement according to storage condition, the groups were divided into 3 : Group A : Stored in waste at $37^{\circ}C$ for 24 hours. Group B : 1000 cycles thermocycled between $5^{\circ}C\;and\;55^{\circ}C$ in water. Group C : Stored in water at $37^{\circ}C$ for 30 days. The results were as follows. 1. Failure was found at gold screw in all specimens of group 1 & 2. 2. The bond strength in group 1 and 2 was 189.86 and 188.14kgf. There was no statistically significant difference between group 1 and 2(P>0.05). 3. The bond strength of group A, B and C was 53.28, 45,86 and 39.29Kgf. There result suggest the advantage of an improved fit of superstructure to the abutment and a simple procedure. But there was a measurable decrease of the bond strength according to storage condition. So, Further research is necessary to evaluate of the implant prosthesis luted with resin cement between gold cylinder and superstructure.

• 자원환경지질
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• 제27권5호
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• pp.451-458
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• 1994

Geochemical studies on gold-bearing quartz veins and granitic wallrocks from the Mugeug mine were carried out in order to investigate primary dispersion patterns of elements and to quantify primary dispersion widths of elements with distance from the gold-bearing quartz veins. The best fitting model of dispersion pattern in altered wallrock around the gold-bearing quartz veins is an exponential function for Au, As, Sb, $Na_2O$ and Sr, and a quadratic function for CaO, $K_2O$, MnO, Ba, Rb and Cs. The primary dispersion widths are 15~343 cm in the hanging wall, and 33~173 cm in the footwall. The width of primary dispersion in the hanging wall is twice as thick as that in the footwall mainly due to the thermal effect and volatile components. The primary dispersion width is increased as the increase of gold-bearing quartz vein width and contents of As and Sb in gold-bearing quartz veins, but is not related to Au content in gold-bearing quartz veins.

• 대한치과보철학회지
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• 제37권6호
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• pp.825-834
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• 1999

Recently, various implant cylinders were supplied. especially received gold cylinders, cast cylinders produced from premade gold and plastic cylinders and plastic cylinders. This study measured and compared precise fit produced when using conventional gold and plastic cylinders. The comparative fit of lapped and non-lapped castings made from plastic pattern was examined. The implant/abutment interface fit was evaluated by scanning electron microscopy(SEM) for each of four cylinders. The following results were obtained: 1. The case of plastic cylinder showed $9.67{\pm}1.50{\mu}m$ gap when Steri-Oss fixture was connected. 2. The case of lapped casting made from plastic cylinder showed $3.01{\pm}2.81{\mu}m$ gap when Steri-Oss fixture was connected. 3 The case of gold/plastic cylinder showed $9.80{\pm}1.68{\mu}m$ gap when Steri-Oss fixture was connected. 4. The case of gold cylinder showed ${5.47{\pm}2.43\mu}m$ gap when Steri-Oss fixture was connected. 5. In case of each cylinder which was connected with Steri-Oss fixture, the size of gap was showed less in the order of the case of gold/plastic cylinder, the case of plastic cylinder, the case of gold cylinder and the case of lapped casting made from plastic cylinder As results of this study, the use of premade gold cylinder offers an advantage over plastic pat-terns in precise fit. When plastic patterns are used, polishing of implant cylinder components should provide precise fit.

• Progress in Superconductivity
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• 제2권1호
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• pp.51-55
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• 2000

A $Y_1Ba_2Cu_3O_{7-\delta}$ square spiral microstrip antenna (YBCO antenna) was epitaxially grown on a $LaAlO_3$ substrate by laser ablation. Also fabricated was a gold square spiral microstrip antenna (gold antenna) having the same structure as that of the YBCO antenna in order to compare the properties of both antennas. Both the YBCO antenna and the gold antenna were operated in Ku (12-18 GHz) band, and their properties such as the return loss, SWR, power gain, and radiation patterns were investigated at 77 K. The return loss below -10 dB was obtained in two frequency ranges, i.e., 14.05-14.90 GHz, and 16-18 GHz for the YBCO antenna at 77 K (YBCO superconducting antenna), and in the frequency range of 15.05-17.60 GHz for the gold antenna at 77 K. The SWR bandwidths are 0.85 GHz and 2 GHz for the YBCO superconducting antenna, and 2.55 GHz for the gold antenna at 77 K. The gain improvement of the superconducting YBCO antenna over the gold antenna at 77 K was about 10 dB in the frequency range of 16 GHz to 18 GHz. The radiation patterns show the YBCO superconducting antenna has the omni-directional property of a spiral antenna.

• 자원환경지질
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• 제17권2호
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• pp.91-100
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• 1984

The Gwangyang gold deposits geologically consist of granitic gneiss, metatectic gneiss and porphyroblastic gneiss which correspond to Jirisan gneiss complex. The formations of Gyeongsang system lies unconformably on these gneisses and are intruded by diorite, porphyritic andesite and Bulgugsa granites. Goheung districts are composed of quartz schist, andesitic rock, tuff and granite. The Gwangyang gold deposits are gold bearing fissure filling veins. The vein thickness varies from 15cm to 40cm and they consist of 7-10 layers in parallel. The Goheung copper deposits are sulphide bearing quartz veln which filled the fracture in andesitic rock and biotite granite. The contact zone of these rocks is partially altered. The mineral paragenesis of the Gwangyang and Goheung districts is pyrite, arsenopyrite, pyrrhotite, chalcopyrite, sphalerite, galena, sericite, quartz and calcite. The variation trends of FMA and A'KF triangular diagrams and the differentiation index (norm, Q + Or + Ab) versus oxides diagrams is similar to the Gyeonsang basin igneous rocks. From the trace element analysis of 10 samples of country rocks, wall rocks and veins, the distribution of copper and lead contents display a correlative distribution pattern in relation to gold and silver. Homogenization temperature of fluid inclusions range from $200^{\circ}C$ to $270^{\circ}C$ in quartz from the Gwangyang gold vein and the size of fluid inclusion range from 0.01mm to 0.04mm. The fluid inclusions are mainly one or two phase and the filling degree of the inclusions varies from 85 to 95.

• Transactions on Electrical and Electronic Materials
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• 제10권3호
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• pp.85-88
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• 2009

This report demonstrates the immobilization of uniformly sized gold nanoparticles (AuNPs) on UV cross-linked poly(4-vinylpyridine) (P4VP) polymer thin films and the preparation of micropatterned structures of AuNPs on these films. The polymer thin films were prepared by a spin-coating of P4VP onto a cleaned silicon wafer surface. Upon UV irradiation, these films were then photo cross-linked. Gold nanoparticles were immobilized by immersing the polymer surface in a colloidal solution of gold nanoparticles stabilized by citric acid. The morphology of the films and the immobilization of AuNPs were studied by atomic force microscopy (AFM) and UV-visible spectroscopic techniques. The micropatterned gold structures that were produced on the polymer surface are delineated by combining with the photolithographic method. While untreated and simply spin coated films were physisorbed and unstable that could be easily removed by rinsing with a solvent, the cross-linked and AuNPs immobilized P4VP films were found to be highly stable even after repeated solvent extractions.

• 자원환경지질
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• 제54권2호
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• pp.213-232
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• 2021

Ore criteria at the Sheba Deposit indicate orogenic mineralization type. Rocks and mineral assemblages suggest low formation-temperature of green-schist facies. Pyrite found in two generations; Type1 is irregular grains, contains higher arsenic and gold contents, compared to the relatively younger phase Type2 pyrite, which is composed of euhedral grains, found adjacent to late quartz-carbonate veins or at rims of type1 pyrite. Two gold generations were identified; type1 found included in sulphides (mainly pyrite). The second gold type was remobilized (secondary) into free-lodes within silicates (mainly quartz). Gold fineness is high, as gold contains up to 95 wt. % Au, Ag up to 3.5 wt. %, and traces of Cu, Ni, and Fe. Pyrite type2 contains tiny mineral domains (rich in Al, Mn, Hg, Se, Ti, V, and Cr). Zoning, and replacement textures are common, suggesting multiple mineralization stages. The distribution and relationships of trace elements in pyrite type2 indicate three formation patterns: (1) Al, Mn, Hg, Se, Ti, V, Cr, and Sn are homogeneously distributed in pyrite, reflecting a synchronous formation. (2) As, Ni, Co, Zn, and Sb display heterogeneous distribution pattern in pyrite, which may indicate post-formation existence due to other activities. (3) Au and Ag show both distribution patterns within pyrite, suggesting that gold is found both in microscopic phases and as chemically bounded phase.

• 대한치과의사협회지
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• 제22권4호통권179호
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• pp.269-269
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• 1984

• 한국광물학회지
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• 제16권3호
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• pp.265-280
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• 2003

인리형 분지인 백악기 음성분지와 단층 접촉하는 무극 광화대는 백악기 흑운모 화강암을 모암으로 하여 배태된 금$.$은광상들로 구성된다. 무극 광화대내 금$.$은광상들은 북측의 무극광산으로부터 남측의 태극광산까지 서로 다른 금$.$은 품위비, 광석광물의 종류 및 산출 빈도 등을 보이며 열수변질대 분포 특성에 있어서도 상이한 공간적 분포특성을 보인다. 비교적 높은 금$.$은 품위비를 보이는 금봉광산은 복성맥의 구조를 보이며 석영맥으로부터 견운모대 \$\longrightarrow$ 아견운모대 \$\longrightarrow$ 프로필리틱대 \$\longrightarrow$ 아프로필리틱대의 열수변질대가 수평적으로 발달하는 특징을 보인다. 광화대 최남단에 위치하는 태극광산은 상대적으로 낮은 금$.$은비를 보이며 망상 세맥을 중심으로 프로필리틱대 \$\longrightarrow$ 아프로필리틱대의 순서로 열수변질대가 발달한다. 열수변질대의 수직적 변화는 대체로 변질대 하부에서 견운모대가 우세하나, 상부에서는 프로필리틱대가 광범위하게 분포하며, 점토대가 불연속적으로 중첩되는 특징을 보인다. 이러한 열수변질대의 상이한 수평$.$수직적 분포 특성은 각 광산의 열수계의 차이를 반영한 것으로, 금봉광산은 비교적 고온$.$고염도와 물-암석 상호반응이 진행된 광화 유체로부터 견운모대가 형성되었으며, 태극광산은 상대적으로 저온 저염도와 물-암석 상호반응이 미약한 광화 유체에 의하여 프로필리틱대가 형성된 것으로 해석된다. 이런 열수계의 차이는 각 광산이 열수계의 열적 중심(무극광산)에 위치하는지 또는 외곽부(태극광산)에 위치하는지에 따라 열수변질대 분포 양상과 금$.$은비 분포 양상의 차이를 유도한다. 따라서 무극 지역 탐사시 열적 중심부에 해당하는 고온의 지온 구배가 형성되는 지역과 물-암석 상호반응에 의한 견운모 변질작용이 우세한 지역을 고품위대 탐사 지침으로 제시할 수 있다.

• 한국가구학회지
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• 제18권3호
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• pp.195-204
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• 2007

The house method of today is the house form which is composed inside the space where it is unified in social change. Also the life method from left was exchanged with stand-up meal and it became simplification and also the form of So-ban changed in the life method which is controlled. If the ship construction trillion So-ban was the furniture which is used with putting first and today the So-ban with variation of form or the material changed with entirely different role. The So-ban of today was used in the pattern element which is form freely to appear, dual anger there is a possibility of knowing the fact that it is turning out with the So-ban which expresses a geometric pattern with the present-day sense. Today of the So-ban it will pattern it will rightly use Beak-je, the feature person who is the possibility this pattern showing It is soft with the sharp, soft beauty of curved line and rectilinear which is refined, omission and emphasizing which are bold today It applied in So-ban design.