• 한국막학회:학술대회논문집
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• 한국막학회 1994년도 추계 총회 및 학술발표회
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• pp.8-11
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• 1994

Disposal of hazardous ions in the aqueous streams is a significant industrial waste problem.. Waste streams from electronics, electroplating, and photographic industries contain metal ions such as copper, nickel, zinc, chromium(IV), cadmium, aluminum, silver, and gold, amongst others in various aqueous solutions such as sulfates, chlorides, fluorocarbons, and cyanides. Typical plating solutions having similar compositions are listed in Table 1. Spent process streams in catalyst manufacturing facilities also contain precious metals such as Ag, Pt, and Pd. Developing an effective recovery process of these metal ions for reuse is important.

• 한국표면공학회지
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• 제33권5호
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• pp.381-386
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• 2000

It was found that colloidal silica sprayed to the galvanized steel sheet apparently made the molten zinc layer solidified to be the randomly oriented fine grains. Its spraying effect was also little affected by steel temperature that had been considered as one of the major operating factors in this process. From the results of surface analysis, it is considered that aluminum dissolved in coating layer reduces silica to silicon by the oxidation-reduction reaction, and that the reduced silicon acts as a more effective nucleus in solidification reaction than phosphate salt, siica and alumina.

• 수산해양교육연구
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• 제19권1호
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• pp.129-136
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• 2007

The component parts of the shell plate of a ship are steel. but the screw propeller or the bow thruster is a compound of bronze, nickel and aluminum. On account of the these different components between metals of the shell plate, the screw propeller and the bow thruster, which are underwater, the shell plate of a ship is corroded by the action of ionization. Authors investigated the corrosion loss of the zinc anodes which were attached to the bottom shell of the training ship Kaya for about two years. The obtained results were as follows:1. In case of the shell plate the difference of the corrosion loss according to port and starboard was almost nothing. But the corrosion loss of the forward part was more than that of the aftward part.2. There was little difference in the corrosion loss between the forward and the aftward part on the bilge keel.3. The corrosion loss of the fore, midship and aft part on the false keel were 24.7%, 22.4% and 23.9% respectively.4. The corrosion loss of the fore and the aft part on the false keel was more than that of the midship part.5. The corrosion loss of the bow thruster was greater than any other parts.6. The nearer the zinc anode to the screw propeller the more the corrosion loss on the stern frame, and the situation was also same as on the rudder.

• 한국산학기술학회논문지
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• 제16권2호
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• pp.1555-1562
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• 2015

금속 산화물 반도체는 독특한 전기 광학적 특성, 높은 표면적 등으로 인해 태양전지, 센서, 광소자 및 디스플레이 등 여러 분야에 걸쳐 응용되고 있다. 금속 산화물 가운데 우수한 물리 화학적 특성을 가지는 산화아연은 3.37 eV의 넓은 밴드갭 에너지와 60 meV의 큰 엑시톤 결합에너지를 갖는 n-형 반도체로서 산화아연에 양이온을 도핑하여 전기 광학적 특성을 보완하는 연구가 진행되고 있다. 본 연구는 알루미늄이 도핑 된 산화아연을 마이크로파 수열합성법으로 합성하였다. 전구체의 종류와 몰 비 등의 반응 변수를 조절하여 최적의 결정형상과 광학적 특성을 갖는 산화아연을 합성하였으며, 알루미늄을 도핑하여 광학적 특성 변화를 시도하였다. 합성된 입자는 SEM, XRD, PL, UV-Vis 분광기 및 EDS 등의 기기분석을 통해 광학적, 물리 화학적 특성을 확인하였다.

• Current Photovoltaic Research
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• 제2권1호
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• pp.14-17
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• 2014

In this paper, indium reduced materials for transparent conductive electrodes (TCE) were fabricated and their physical properties were evaluated. Two of materials, indium-zinc-tin oxide (IZTO) and aluminum (Al) were selected as TCE materials. In case of IZTO nanoparticles, composition ratios of In, Zn and Sn is 8:1:1 were synthesized. Size of the synthesized IZTO nanoparticles were less than 10 nm, and specific surface areas were about $90m^2/g$ indicating particle sizes are very fine. Also, the IZTO nanoparticles were well crystallized with (222) preferred orientation despite it was synthesized at the lowered temperature of $300^{\circ}C$. Composition ratios of In, Zn and Sn were very uniform in accordance with those as designed. Meanwhile, Al was deposited onto glass by sputtering in a vacuum chamber for mesh architecture. The Al was well deposited onto the glass, and no pore was observed from the Al surface. The sheet resistance of Al on glass was about $0.3{\Omega}/{\square}$ with small deviation of $0.025{\Omega}/{\square}$, and adhesion was good on the glass substrate since no pelt-off part of Al was observed by tape test. If the Al mesh is combined with ink coated layer which is consistent of IZTO nanoparticles, it is expected that the good and reliable metal mesh architecture for TCE will be formed.

• 전기화학회지
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• 제4권4호
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• pp.166-171
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• 2001

KOH 강염기성 전해질을 사용하는 알루미늄-공기 단위전지에서 합금원소. 전해질에 첨가하는 억제제의 종류, 억제제의 농도, 전해질 온도, KOH 농도, 방전전류밀도 등을 변화시키면서 수소발생속도를 측정하였으며, 각 실험 변수들이 미치는 영향에 대해 조사하였다. 전해질 용액에 ZnO를 포화농도로 첨가하면 첨가하지 않은 경우에 비해 수소발생속도를 $50\%$ 정도로 억제시킬 수 있는 반면에, ZnAc(Zinc Acetate)는 반응억제제로서 역할을 하지 못하였다. KOH 농도와 전해질온도가 높을수록 ZnO의 반응속도 억제효과가 상승하였다. 알루미늄의 수소발생속도는 KOH 농도와 전류밀도에 대해 1차선형 증가함수의 경향을 가지며, 온도에 대해 지수형 증가함수로 나타났다.

• 펄프종이기술
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• 제40권5호
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• pp.1-10
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• 2008

Synthetic mineral microparticles (SMM) is a patented system which has been developed to promote drainage of water and retention of fine particles during papermaking. It is shown in patents that the SMM system can have advantages in both of drainage and retention, compared with montmorillonite (bentonite), which is one of the most popular materials presently used in this kind of application. Turbidity and gravity drainage time were measured using a Britt-Jar test with representative SMM formulations, in order to confirm the efficacy of SMM covering a wide range of compositions and discover effects of some key variables that have the potential to lead to unexpected advantages in terms of the effectiveness of the microparticles, when used in combination with a cationic polyacrylamide treatment of papermaking furnish. An iron silicate showed highest retention performance, as well as suitably fast drainage time relative to other metal silicate and bentonite. Zinc silicate improved retention and drainage. SMM synthesized from aluminum sulfate ($Al_2(SO_4){_3}$) did not show a benefit in retention and drainage, relative to bentonite. SMM synthesized from aluminum chloride ($AlCl_3$) performed better in drainage and retention than bentonite when the Al/Si ratios were 0.76 and 1.00. It was found that when the Al/Si ratio and neutralization are considered, pH variation due to the change of Al/Si ratio can be a key factor to control the size of primary metal silicate particles and the degree of coagulation of the primary particles.

• 한국표면공학회지
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• 제42권3호
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• pp.128-132
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• 2009

Transparent conducting thin films of indium tin oxide(ITO) co-sputtered with aluminum-doped zinc oxide(AZO) were deposited on glass substrate by dual magnetron sputtering. It was found that the electrical properties and structural characteristics of the films are significantly changed according to the sputtering power of the AZO target. The IAZTO film prepared with D.C power of ITO at 100 W and R.F power of AZO at 50 W shows an electrical resistivity of $4.6{\times}10^{-4}{\Omega}{\cdot}cm$ and a sheet resistance of $30{\Omega}/{\square}$ (for 150 nm thick). Besides of the improvement of the electrical properties, compared to the ITO films deposited at the same process conditions, the IAZTO films have very smooth surface, which is due to the amorphous nature of the films. However, the electrical conductivity of the IAZTO films was found to be deteriorated along with the crystallization in case of the high temperature deposition (above $310^{\circ}C$). In this work, high quality amorphous transparent conductive oxide layers could be obtained by mixing AZO with ITO, indicating possible use of IAZTO films as the transparent electrodes in OLED and flexible display devices.

• 한국자동차공학회논문집
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• 제14권2호
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• pp.127-135
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• 2006

We analyzed recyclability of the fuel tanks made from steel or aluminum alloy. For a comparison of the fuel tank recyclability, first we had analyzed the process of disassembly in a vehicle and evaluated its disassemblability. Then we evaluated the recyclability for reuse and withdrawal. The processes were more or less same owing to the similarity of fastening method of fuel tank and components. However, the fuel tank of the aluminum alloy was easier (about 5%) to disassembly than the fuel tank of steel. This could be attributed to the differences in weight of steel and aluminium. On light of the withdrawal and reuse, the fuel tank made up of steel needed to plate with zinc or lead due to its anti-corrosiveness. Hence, it required additional processes. In this paper, we were explaining the results of our on going research on the recyclability of fuel tanks made of steel and aluminum alloys. The differences that we found between the fuel tank made up of the aluminum alloy and steel were in their weight, recyclability, disassemblability, anticorrosive property, cost and productivity.

• 산업공학
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• 제21권4호
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• pp.418-434
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• 2008

This paper studied issues in decision making on the production control policy of a cathode plate manufacturing process in zinc refining plant. The present production system has a long lead time from raw materials (aluminum plate) to products (cathode plate) due to many WIP inventories. Because WIP inventories are stocked at each process and moved from one place to another frequently, they are the main cause of inefficiency in the process. In this paper, to solve this problem, several production control policies have been identified and studied. Several simulation models are used to compare the performances of these production control policies. The output lead time and WIP (Work In Process) of real production system are compared with those of simulation models. PUSH, CONWIP, DBR, KANBAN and CONWIP-DBR models have been used to simulate and review the optimized production control policy that achieves the target output quantities with decreased lead time and WIP. The simulation results of each production control policy show that CONWIP and CONWIP-DBR models are the good production control policy under the present production system. Especially in present production system, CONWIP with one parameter is easier control policy than CONWIP-DBR with two parameters. Therefore CONWIP has been selected as the best optimum production control policy. With CONWIP, lead time has been reduced by 97% (from 6,653 to 187 minute) and WIP has been reduced from 1,488 to 53, compared to the present system.