• Korean Journal of Agricultural Science
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• v.14 no.2
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• pp.197-204
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• 1987

In order to know the growth of suspended cells by explant sources, the change of nitrogen contents of cultured cells following the growth periods, capability of micro-callus formation according to cell plating methods, growth of suspended cells on various media, and efficiency of micro-callus formation by using growth regulators and different N strengths were investigated. 1. When suspension culture was tried by using the callus induced from internode and petiole, cell fresh weight and packed cell volume increased with similar way and the growth reached at stationary phase after 12 culture days. 2. N-contents of cultured cells increased upto 3 days and decreased around 6days. But the values increased again upto 9 days, after that they showed gradual decreases. 3. Of cell plating methods, embedding method was the best for micro-callus formation. 4. Growth of suspened cells showed the rest performanoes, when they were cultured on LM medium with 1/2N strengths and BAP 0.01.2.4-D 0.1, and NAA $1.0mg/{\ell}$, after 15 cultured days(upto 76.9 folds). LM medium was better than MS or GD. The combination of auxin and cytokinin was better for cell growing than auxin-treatment only. 5. Micro-callus from single cell and small cell aggregates was formed only on MS and LM media with 2,4-D $1.0mg/{\ell}$.

• Journal of the Korean institute of surface engineering
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• v.10 no.1
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• pp.1-18
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• 1977

To support the domestic plating industry concerning localized products, survey was conducted in with chemicals and properties of plating solution. Collected samples from 55 factories throughout the country were investigated by spectigated by spectrograph, Hull cell test chemical analysis method to find major chemical components of the plating solution.

• Clean Technology
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• v.11 no.3
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• pp.153-164
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• 2005

This study found a reliable evaluation for four kinds of pb-Free plating solutions and it's layers, through pure Sn, SnAg, SnBi and SnCu. These four kind of solutions are widely used to pb-Free plating. Hull-cell, Harring-blum, coverage, throwing power, current efficiency, stability, life-time, composition, hardness, roughness, abrasion, scratch, solderability, corrosion, contact angle, morphology, SIR(Surface insulation resistance) and Whisker test were experimented. Also, Using ICP, XRF, FE-SEM, EDS, temperature/humidity chamber, solderability tester, hardness tester, roughness tester, abrasion tester, salt spray tester, contact angle tester, SIR tester, and microscope. In this paper could be shown the systematic and various analysis for reliability about four kinds of pb-Free plating solutions, processes and it's deposit surface.

• Journal of Electrochemical Science and Technology
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• v.1 no.2
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• pp.117-120
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• 2010

Materials used as fuel cell electrode should be light, high conductive, high surface area for reaction, catalytic surface and uniformity of porous structure. Nickel is widely used in electrode materials because it itself has catalytic properties. When used as electrode materials, nickel of only a few im on the surface may be sufficient to conduct the catalytic role. To manufacture the nickel with porous structure, Electroless nickel plating on carbon fiber be conducted. Because electroless nickel plating is possible to do uniform coating on the surface of substrate with complex shape. Acidic bath and alkaline bathe were used in electroless nickel plating bath, and pH and temperature of bath were controlled. The rate of electroless plating in alkaline bath was faster than that in acidic bath. As increasing pH and temperature, the rate of electrolee plating was increased. The content of phosphorous in nickel deposit was higher in acidic bath than that in alkaline bath. As a result, the uniform nickel deposit on porous carbon fiber was conducted.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.10a
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• pp.342-345
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• 2009

Electro galvanized steel is electroplated cold roller steel for improving corrosion resistance and paintability, and is widely used in automobiles and home appliances. In the electroplating line for manufacturing electro galvanized steel if plating process is carried out with impurity on conductor roll surface, the defects in manufacturing process occurs because of steel fault. For quality, polishing is always required to separate impurity on surface of conductor roll. In this study, finite element analysis of wear for polisher brush is carried out for replaced time of it.

• Transactions on Electrical and Electronic Materials
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• v.16 no.1
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• pp.20-24
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• 2015

We studied the relationship between the surface smoothness of the internal Cu ribbon and the morphology of the Sn-Pb plating layer for solar cell modules. A bumpy surface was observed on the surface of the solar ribbon, which caused irregular reflection of light. Large, Pb-rich, primary ${\alpha}$-phases were found below the convex surface of the solar ribbon, passing from the surface of the internal Cu ribbon to the surface of the plating layer. The primary ${\alpha}$-phases heterogeneously nucleated on the convex surface of the Cu ribbon, and then largely grew to the convex surface of the plating layer. The restriction of the primary ${\alpha}$-phase's formation was enabled by enhancing the smoothness of the Cu ribbon's surface; it was also possible to increase the adhesive strength and decrease contact resistance. We confirmed that the solar ribbon's surface smoothness depends on the internal Cu ribbon's surface smoothness.

• Korean Journal of Materials Research
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• v.6 no.6
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• pp.568-575
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• 1996

The double sided buried contact(DSBC)silicon solar cell processing requires doping of the rear and front grooves with boron and phosphorus respectively. The successful electroless plating of these grooves with the appropriate metals haave been found to depend on the boron conditions for the rear fingers. However, an increased understanding of electroless plating has removed this restriction. Thus the DSBC cells using different boron conditions can be electrolessly plated with ease. This paper presents the recent work done on metallizing the double sided buried contact silicon solar cells with heavily doped boron grooves. The cells results indicate that, the heavier the boron grooves, the poorer the cell performance because of the probable higher metal contact recombination associated with boron grooves.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.6
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• pp.370-375
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• 2016

In this paper, we investigated the electrical properties of crystalline silicon solar cell fabricated with Ni/Cu/Ag plating. The laser process was used to ablate silicon nitride layer as well as to form the selective emitter. Phosphoric acid layer was spin-coated to prevent damage caused by laser and formed selective emitter during laser process. As a result, the contact resistance was decreased by lower sheet resistance in electrode region. Low sheet resistance was obtained by increasing laser current, but efficiency and open circuit voltage were decreased by damage on the wafer surface. KOH treatment was used to remove the laser damage on the silicon surface prior to metalization of the front electrode by Ni/Cu/Ag plating. Ni and Cu were plated for each 4 minutes and 16 minutes and very thin layer of Ag with $1{\mu}m$ thickness was plated onto Ni/Cu electrode for 30 seconds to prevent oxidation of the electrode. The silicon solar cells with KOH treatment showed the 0.2% improved efficiency compared to those without treatment.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.1
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• pp.88-97
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• 1996

The metallization is the key to determining cell costs, cell performance, and system reliability. Screen printing technology suffers from several limitations affecting mainly the front grid. The buried contact solar cell (BCSC) was specifically desinged to be compatible with low cost, mass production techniques and avoid the conventional metallization problem. By using electroless plating technique, we performed this metallization inexpensively and reliably. This paper presents the details of the optimization procedure of metallization schemes on laser grooved cell surfaces. Commercially available Ni, Cu and Ag plating solutions were applied for the cell metallization. The application of those solutions on the buried contact front metallization has resulted in an cell efficiency of 18.8%. The cell parameters are an open circuit voltage of 651 mV, short circuit current density of 37.1 mA/$\textrm{cm}^2$, and fill factor of 77.8 %. The efficiency of over 18 % was achieved in the above 90% of the batch.

• BMB Reports
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• v.32 no.3
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• pp.266-272
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• 1999

The insulin-like growth factor (IGF) system consisting of IGF-I, IGF-II, IGF-receptors, and IGF-binding proteins (IGFBP) regulates the proliferation of a variety of cancer cell types. To examine whether a decrease in endogenous IGFBP-3 stimulates proliferation or inhibits differentiation, Caco-2 cells, a human colon adenocarcinoma cell line, were stably transfected with an anti-sense IGFBP-3 expression construct or pcDNA3 vector as control. Accumulation of IGFBP-3 mRNA and secretion of IGFBP-3 into serum-free conditioned medium, 9 days after plating, were significantly lower in Caco-2 cell clones transfected with anti-sense IGFBP-3 cDNA compared to the controls. The anti-sense clones grew at a similar rate to the controls for 8 days after plating, but achieved a higher final density between days 10 and 12. The levels of sucrase-isomaltase mRNA, a marker of enterocyte differentiation of Caco-2 cells, were lower in the anti-sense clones examined on day 9. In conclusion, proliferation of Caco-2 cells can be stimulated by lowering endogenously-produced IGFBP-3.