• 대한방사성의약품학회지
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• 제4권2호
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• pp.80-84
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• 2018

$[^{13}N]$Ammonia or $[^{13}N]NH_3$ is one of the most widely used PET tracer for the measurement of MBF. To produce $[^{13}N]NH_3$, devarda's alloy which contains aluminum, copper and zinc is used for the purpose of reduction from $^{13}N$-nitrate/nitrite to $[^{13}N]NH_3$. Since aluminum has neurotoxicity and renal toxicity, the amount of it should be carefully limited for the administration to the human body. Although USP and EP provide a way to identify the aluminum ion concentration, there are some difficulties to perform. Therefore, we tried to develop the modified method for verifying aluminum concentration of test solution. We compared color between test and standard solutions using chrome azurol S in pH 4.6 acetate buffer. We also tested color change of test and standard solutions according to pH, amounts and the order of reagent and time difference These results demonstrated that the color change of the solution can reflect quantitatively measure aluminum ion concentration. We hope the method is to be used effectively and practically in many sites where $[^{13}N]NH_3$ is produced.

• Corrosion Science and Technology
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• 제9권6호
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• pp.276-280
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• 2010

Copper(Cu) as an interconnecting metal layer can replace aluminum (Al) in IC fabrication since Cu has low electrical resistivity, showing high immunity to electromigration compared to Al. However, it is very difficult for copper to be patterned by the dry etching processes. The chemical mechanical polishing (CMP) process has been introduced and widely used as the mainstream patterning technique for Cu in the fabrication of deep submicron integrated circuits in light of its capability to reduce surface roughness. But this process leaves a large amount of residues on the wafer surface, which must be removed by the post-CMP cleaning processes. Copper corrosion is one of the critical issues for the copper metallization process. Thus, in order to understand the copper corrosion problems in post-CMP cleaning solutions and study the effects of DC biases and post-CMP cleaning solution concentrations on the Cu film, a constant voltage was supplied at various concentrations, and then the output currents were measured and recorded with time. Most of the cases, the current was steadily decreased (i.e. resistance was increased by the oxidation). In the lowest concentration case only, the current was steadily increased with the scarce fluctuations. The higher the constant supplied DC voltage values, the higher the initial output current and the saturated current values. However the time to be taken for it to be saturated was almost the same for all the DC supplied voltage values. It was indicated that the oxide formation was not dependent on the supplied voltage values and 1 V was more than enough to form the oxide. With applied voltages lower than 3 V combined with any concentration, the perforation through the oxide film rarely took place due to the insufficient driving force (voltage) and the copper oxidation ceased. However, with the voltage higher than 3 V, the copper ions were started to diffuse out through the oxide film and thus made pores to be formed on the oxide surface, causing the current to increase and a part of the exposed copper film inside the pores gets back to be oxidized and the rest of it was remained without any further oxidation, causing the current back to decrease a little bit. With increasing the applied DC bias value, the shorter time to be taken for copper ions to be diffused out through the copper oxide film. From the discussions above, it could be concluded that the oxide film was formed and grown by the copper ion diffusion first and then the reaction with any oxidant in the post-CMP cleaning solution.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.1026-1029
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• 2002

We report the electric properties of organic light emitting diodes (OLEDs) by controlling the carrier density according to the crystalline of copper(II) phthalocyanine(CuPc) and the irradiation light intensity. OLEDs were constructed with indium tin oxaide (ITO)/CuPc/triphenyl-diamin (TPD)/tris-(8-hydroxyquinoline)aluminum (Alq3)/Al. The transport properties of OLEDs were changedby the heat-treatments of CuPc. The irradiation of red and blue light exciting CuPc, TPD and Alq3. And then we observed the carrier density of OLEDs.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1997년도 춘계학술대회논문집
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• pp.140-143
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• 1997

The present study is concerned with the hydrostatic extrusion process of copper-clad aluminium bar to investigate the basic flow characteristics. Considering the bonding mechanism of bi-metal contact surface as cold pressure welding, the normal pressure and the contact surface expansion are selected as process parameters governing the bonding condition. The critical pressure required for the bonding at the interface is obtained by solving a "local extrusion" using a slip line meyhod. A viscoplastic finite element method is used to analyze the steady state extrusion process. The boundary profile of bi-metal rod is predicted by tracking a particle path adjacent to interface surface. The variations of contact surface area and the normal pressure along the interface profile are predicted and compared to those by experiments.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.1
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• pp.304-307
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• 2003

Replacement of aluminum by copper for interconnections in the semiconductor industry has raised a number of important issues. The integration of copper interconnection can be carried out by CMP(chemical mechanical polishing) is used to planarize the surface topography. In this experiments, we evaluated the optimization of several conditions for chemical additives during Cu CMP process. It was presented that the main cause of grown particle size is tartaric acid. The particle size was in inverse propotion to a quantity of bead and the time of milling process. The slurry stabilizer and oxidizer have been shown to have very good effect by addition in later milling process.

• 한국표면공학회지
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• 제29권6호
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• pp.673-677
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• 1996

Copper phthalocyanine(CuPc) thick film solar cells were fabgricated byspin coating and their photovoltaic behavior was studied. Polyvinylidene fluoride (PVdF) was used for the binder. Aluminum and indium were employed as electrode metals to form Schottky contact to CuPc layer. The cells showed rectifying J-V characteristics in the dark and photovoltaic effect associated with white light irradiation. The photovoltaic performance of the cells strongly depended on contact metals, in which the formation of oxide layer between binder layer and electrode interface affected the solar cell. Influnce of the CuPc layer thickness, CuPc/PVdF ratio on the photovoltaic performance of the cells were also examined.

• 한국의류학회지
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• 제27권9_10호
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• pp.1134-1143
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• 2003

The purpose of this study is to investigate surface color change and effects of mordants on the K/S values of silk and wool fabrics dyed with Lac extract, according to the mordanting methods and conditions such as temperature, concentration and time of the mordanting bath. The results were as follow; 1 K/S values of the silk and wool fabrics according to the temperature of the mordanting bath were shown a slight decline beyond 40$^{\circ}C$. 2. Surface color of the silk changed from red to reddish purple and that of the wool showed red tone when mordanted with Aluminum postassium sulfate, Copper acetate and Copper (II) sulfate regardless of the mordanting conditions. 3. The light and dry cleaning fastness of silk and wool fabrics dyed with Lac extract according to the mordanting methods were very good.

• 한국염색가공학회지
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• 제11권4호
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• pp.39-49
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• 1999

In order to study the properties of cochineal colors, uv-visible spectra of cochineal colors solution, dyeing properties on the wool in several dyeing conditions and thermodynamic parameters were investigated. UV-visible spectra of cochineal colors solution showed hypochromic effect with the lapse of irradiation time but bathochromic shift with decreasing acidity of solution and addition of metallic ions. The concentration of cochineal colors in wool fiber increased with the increase of dyeing temperature, time, and acidity of initial dyebath. The value of apparent diffusion coefficients and standard affinities of dyeing decreased with the increase of dyeing temperature. The standard heats of dyeing$(\Delta{H}^\circ)$ and variation of entropy$(\Delta{S}^\circ)$ increased with the increase of concentration of initial dyebath. The activation energy$(E_a)$ were calculated to be 1.399~2.595kcal/mol in condition of 6~1%(o.w.f) dyebath. Wool fabrics were dyed reddish blue by iron sulfate, copper sulfate, aluminum acetate and tannic acid, and red by tin chloride, respectively. Lightfastness of wool fabrics dyed by cochineal colors were increased by mordant treatment, especially copper sulfate and iron sulfate treatment.

• 한국공작기계학회논문집
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• 제10권5호
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• pp.124-129
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• 2001

The experimental study was the cutting characteristics of non-ferrous metals. The experimental apparatus was used the turning machine and diamond tool. This aimed at lading the optimal cutting conditions by measuring surface farm and roughness. Used non-ferrous metals were aluminum, brass and oxygen-free copper. As well, according to changing cutting conditions such as feed rate by measuring cutting farce and surface roughness and according to cutting conditions the non-ferrous metals studied about cutting properties.

• 공기청정기술
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• 제22권2호
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• pp.40-49
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• 2009

Aluminum thin plate coated with epoxy resin containing about 20wt% brass powder, was applied to fins of heat exchanger. We carried out a series of detailed examinations to evaluate the anti-bacterial performance of the plate and heat exchanger (fan coil unit). In the presence of water or moisture, copper ions which have an anti-bacterial ability eluted from brass powder and showed sufficient effects on many kinds of bacteria. We also evaluated the anti-bacterial performance quantitatively by use of the index API (Anti-bacterial Performance Index) which has already been proposed by authors.