• Journal of the Korean Magnetics Society
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• v.17 no.6
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• pp.238-241
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• 2007

Ni-Cu-Zn ferrites were prepared by the co-precipitation. Physical properties and Microwave absorbing properties were investigated in Ni-Cu-Zn ferrite for the aim of microwave absorbers. From the analysis of X-ray diffraction patterns, we can see that all the particles have only a single phase spinel structure. The loss factor was maximum at sintering temperature $1100^{\circ}C$. The initial permeability of sintered ferrite obtained was an average of 50. We found that the $(Ni_{0.7}Cu_{0.2}Zn_{0.1}O)_{1.02}(Fe_2O_3)_{0.98}$ can be used in ferrite rubber composite microwave absorber when sintering temperature at $1100^{\circ}C$.

• Journal of the Korea Furniture Society
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• v.19 no.5
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• pp.358-364
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• 2008

Wood-inorganic material composite (WIC) was prepared by impregnating wood with copper sulfate ($CuSO_4\;5H_2O$) solution and by immersed wood in sodium carbonate($Na_2CO_3$) solution in order to introduce insoluble copper compounds {copper carbonate hydroxide, $CuCO_3\;Cu(OH)_2$} into the wood to give fungicidal effects in treated-wood. The weight percent gains (WPGs) of treated wood reached maximum value by impregnation of 20% copper sulfate solution and immersion in about 15% sodium carbonate solution for 24 hrs. Inorganic substances were present mainly in the lumina and cross-field pitting of tracheides. These substances were proved to be the insoluble copper carbonate hydroxide against water by the energy dispersive X-ray analyzer in conjunction with a scanning electron microscope (SEM-EDXA). The treated specimens showed high preservative effectiveness because the weight losses were hardly occurred by the fungi degradation test.

• Korean Journal of Heritage: History & Science
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• v.44 no.3
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• pp.132-149
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• 2011

In ancient period, a variety of inorganic or organic pigments had been used as colorants in various kinds of religious and secular paintings such as tomb paintings and wall and scroll paintings in buddhist temples, and danchung(cosmic patterns) for the surface of wooden buildings. This study discusses the results obtained from an analysis of the pigments on the wall paintings of Yeongsanjeon(Hall of Vulture Peak) in Tongdo temple by a qualitative analysis using a field-XRF. The results can be briefly summarized as follows. Firstly, assuming from the major components examined from F-XRF analysis, raw materials of pigment of each color are: red to be Cinnabar(HgS) or Hematite($Fe_2O_3$); white to be White Lead[$2PbCO_3{\cdot}Pb(OH)_2$] in most cases and Calcite($CaCO_3$) or Chalk($CaCO_3$), Kaolin($Al2O_3{\cdot}SiO_2{\cdot}4H_2O$) in some cases; yellow to be Yellow Ocher[$FeO(OH){\cdot}nH_2O$]; black to be carbon(C); green on the painted surface to be Celadonite[$K(Mg,Fe^{2+})(Fe^{3+},Al)(Si_4O_{10})(OH)_2$] in most cases; dark green on the halo of figures to be Malachite[$CuCO_3{\cdot}Cu(OH)_2$], Copper Green[$2CuO{\cdot}CO_2{\cdot}H_2O$] or Atacamite[$Cu_2Cl(OH)_3$]. Secondly, incarnadine and pink were made by mixing with more than two pigments such as red and white for making various tone of colors. The qualitative analysis of pigments on the wall paintings of Yeongsanjeon, in conclusion, displays that the all pigments for ancient periods are inorganis pigments. However, it has the limitation to identify a definite kinds of mineral for each pigment because it was not possible to collect samples from cultural heritage for conducting a crystalline analysis of XRD.

• Membrane Journal
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• v.34 no.1
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• pp.50-57
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• 2024

In this experiment, Pd-Ag-Cu membrane was manufactured using electroless plating on an α-Al₂O₃ support. Pd, Ag and Cu were each coated on the surface of the support through electroless plating and heat treatment was performed for 18 h at 500℃ in H₂ in the middle of electroless plating to form Pd alloy. The surface of the Pd-Ag-Cu membrane was observed through Scanning Electron Microscopy (SEM), and the thickness of the Pd membrane was measured to be 7.82 ㎛ and the thickness of the Pd-Ag-Cu membrane was measured to be 3.54 ㎛. Energy dispersive X-ray spectroscopy and X-ray diffraction analysis confirmed the formation of a Pd-Ag-Cu alloy with a composition of Pd-78wt%, Ag-8.81wt% and Cu-13.19wt%. The gas permeation experiment was conducted under the conditions of 350~450℃ and 1~4 bar in H₂ single gas and H₂/N₂ mixed gas. The maximum H₂ flux of the hydrogen separation membrane measured in H₂ single gas is 74.16 ml/cm²·min at 450℃ and 4 bar for the Pd membrane and 113.64 ml/cm²·min at 450℃ and 4 bar for the Pd-Ag-Cu membrane. In the case of the separation factor measured in H₂/N₂ mixed gas, separation factors of 2437 and 11032 were measured at 450℃ and 4 bar.

• 보존과학연구
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• s.26
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• pp.165-188
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• 2005

From the ancient to these days, there have been used many kinds of pigment which have two types that are inorganic pigment and organic pigment. At the ancient times, natural pigment had been used but the artificially mixed pigment has been used in modern times. By the way, searching for studies has been studied recently, it would be said the ancient pigments such as Danchung, Wall painting and Mural painting are the mainthema. However, studies about the pigments used in modern pictured relics have rarely can be found. Therefore, this analysis of Ilweolokdo would be important at the point of the pigments used in pictures of royal family in modern times and the results can be briefly summarized as below; Firstly, the results of qualitative analysis of the pigments that base or all pigments of picture was detected components of Ca, Fe and As, this results meaning that picture was used filler and basic paint. Secondly, a result of the analysis on the composition elements of the pigments shows that the main components in their composition are ;White - Lead Cyanamide($2PbCO_3$.$Pb(OH)_2$) or Titanium Oxide($TiO_2$)Blue - Ultramarine($2(Na_2O$.$Al_2O_3$ .$2Si_O2$).$Na_2S_2$)Green - Emerald green($C_2H_3A_s3Cu_2O_8$)Gold - Gold(Au), Red-Red Lead($Pb_3O_4$) or Cinnabar(HgS)Black - Carbon(C)Thirdly, X-ray diffraction analysis of crystalline structure for the blue and green pigment peeling off in picture shows that the components of blue pigment is Ultramarine($2(Na_2O$.$Al_2O_3$ .$2Si_O2$).$Na_2S_2$) and green pigment is Emerald green($C_2H_3A_s3Cu_2O_8$). Especially, microcrystalline structure of the green pigment was the shape like a cross section of wood. Consequently, we knew through the analysis of qualitative and microcrystallinestructures seen on the cross section of analyzed pigments layer that the all pigments used in the Ilweoloakdo is possible to use synthetic pigments in modern.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.3
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• pp.7-12
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• 2018

The effects of Ru deposition temperature and post-annealing conditions on the interfacial adhesion energies of atomic layer deposited (ALD) Ru diffusion barrier layer and Cu thin films for the advanced Cu interconnects applications were systematically investigated. The initial interfacial adhesion energies were 8.55, 9.37, $8.96J/m^2$ for the sample deposited at 225, 270, and $310^{\circ}C$, respectively, which are closely related to the similar microstructures and resistivities of Ru films for ALD Ru deposition temperature variations. And the interfacial adhesion energies showed the relatively stable high values over $7.59J/m^2$ until 250h during post-annealing at $200^{\circ}C$, while dramatically decreased to $1.40J/m^2$ after 500 h. The X-ray photoelectron spectroscopy Cu 2p peak separation analysis showed that there exists good correlation between the interfacial adhesion energy and the interfacial CuO formation. Therefore, ALD Ru seems to be a promising diffusion barrier candidate with reliable interfacial reliability for advanced Cu interconnects.

• Journal of Powder Materials
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• v.20 no.2
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• pp.142-147
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• 2013

$YBa_2Cu_3O_{7-y}$ (Y123) powders for the fabrication of bulk superconductors were synthesized by the powder reaction method using $Y_2O_3$ (99.9% purity), $BaCO_3$ (99.75%) and CuO (99.9%) powders. The raw powders were weighed to the cation ratio of Y:Ba:Cu=1:2:3, mixed and calcined at $880^{\circ}C-930^{\circ}C$ in air with intermediate repeated crushing steps. It was found that the formation of Y123 powder was more sensitive to reaction temperature than reaction time. The calcined Y123 powder and a mixture of (Y123 + 0.25 mole $Y_2O_3$ + 1 wt.% $CeO_2$, $Y_{1.5}Ba_2Cu_3O_x$ (Y1.5)) were used as raw powders for the fabrication of poly-grain or single grain superconductors. The superconducting transition temperature ($T_{c,onset}$) of the sintered Y123 sample was 91 K and the transition width was as large as 11 K, whereas the $T_{c,onset}$ of the melt-grown Y1.5 sample was 90.5 K and the transition width was 3.5 K. The critical current density ($J_c$) at 77 K and 0 T of the sintered Y123 was 700 $A/cm^2$, whereas the $J_c$ of the top-seeded melt growth (TSMG) processed Y1.5 sample was $3.2{\times}10^4\;A/cm^2$. The magnetic flux density (H) at 77 K of the TSMG-processed Y123 and Y1.5 sample showed the 0.53 kG and 2.45 kG, respectively, which are 15% and 71% of the applied magnetic field of 3.5 kG. The high H value of the TSMG-processed Y1.5 sample is attributed to the formation of the larger superconducting grain with fine Y211 dispersion.

• Journal of the Korean Magnetics Society
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• v.11 no.3
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• pp.104-108
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• 2001

The effect of specular electron scattering on natural oxidation of free layer in NiO spin valves have been investigated. The magnetoresistance (MR) ratio and the exchange biasing field ( $H_{ex}$) of NiO(600 $\AA$)Ni$_{81}$$Fe_{19}$(50$\AA$)/Co(7 $\AA$)/Cu(20 $\AA$)/Co(7 $\AA$)Ni$_{81}$$Fe_{19}$(70 $\AA$) spin valves were increased from 4.9 % to 7.3 %, and 110 Oe to 170 Oe after natural oxidation in the atmosphere for 80 days, respectively. The sheet resistivity p decreased from 28$\mu$$\Omega$m to 17$\mu$$\Omega$m, but $\Delta$$\rho$ did not almost change after the oxidation. The spin valves enhanced by the specular electron scattering in the natural]y Co/NiFe/NiFe $O_{x}$ free layer were confirmed from the depth profiles using Auger electron spectroscopy.scopy..

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.1
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• pp.1-8
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• 2017

Cu/Mn/Ce catalysts for water gas shift (WGS) reaction were synthesized by urea-nitrate combustion method with the fixed molar ratio of Cu/Mn as 1:4 and 1:1 with the doping concentration of Ce from 0.3 to 0.8 mol%. The prepared catalysts were characterized with SEM, BET, XRD, XPS, $H_2$-TPR, $CO_2$ TPD, $N_2O$ chemisorption analysis. The catalytic activity tests were carried out at a GHSV of $28,000h^{-1}$ and a temperature range of 200 to $400^{\circ}C$. The Cu/Mn(CM) catalysts formed Cu-Mn mixed oxide of spinel structure ($Cu_{1.5}Mn_{1.5}O_4$) and manganese oxides ($MnO_x$). However, when a small amount of Ce was doped, the growth of $Cu_{1.5}Mn_{1.5}O_4$ was inhibited and the degree of Cu dispersion were increased. Also, the doping of Ce on the CM catalyst reduced the reduction temperature and the base site to induce the active site of the catalyst to be exposed on the catalyst surface. From the XPS analysis, it was confirmed that maintaining the oxidation state of Cu appropriately was a main factor in the WGS reaction. Consequently, Ce as support and dopant in the water gas shift reaction catalysts exhibited the enhanced catalytic activities on CM catalysts. We found that proper amount of Ce by preparing catalysts with different Cu/Mn ratios.

• Conservation Science in Museum
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• v.3
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• pp.43-50
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• 2001

This article is about a joint project carried out by the National Museum of Korea and the Tokyo Cultural Properties Research Institute for the conservation of central Asia Wall painting that has been selected for the exhibition at the new Seoul National Museum of Korea at Yongsan. The investigation of the wall painting revealed very useful information. This includes the condition of the object, and the identification of evident damage, such as cracks, loss of pigment, plus materials and methods employed during the object's creation, as well as previous conservation treatment. The object was mainly made by applying plaster to the body (wall) that consisted of a mixture of soils and rice straws. Then, on the surface of the wall-painting, pigments were used to draw and to colour it. As a part of the investigation, radiocarbon dating was conducted using straw samples taken from the object. The result indicates that the object is probably dated form between the end of the 10th Century and the beginning of the 13th Century. The result of X-ray diffraction also revealed the composition of the pigments used on the surface. These are 1. gypsom [Ca(SO₄)·2H₂O], CaSO₄ and Calcite (CaCO₃) and Calcite (CaCO₃) that were used for the white background. 2. Pb₃O₄ and led Arsenate [Pb(As₂O₆) that were used for the red colouring. 3. Cuprite (Cu₂O), Arsenolite (As₂O₃) and Arsenic Oxide (As₂O₄) that were used for the green colouring.