• Korean Journal of Environmental Biology
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• v.22 no.2
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• pp.265-272
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• 2004

Biological characteristics of anodic electrolyzed water were investigated in this study. Linear DNAs which were incubated at $4^\circ{C}$ and $25^\circ{C}$ for 10 mins in the anodic electrolyzed water were degraded about 40% and 50%, respectively. But the DNA was amplified pretty well without any degradation through polymerase chain reaction in the presence of anodic electrolyzed water. Protein degradation hardly occurred in the distilled water during entire incubation time of 7 days, while protein began to be degraded from 4 days in the anodic electrolyzed water. Rice seeds could germinate in the distilled water and anodic electrolyzed water with the same germination ratio, however, the anodic electrolyzed water inhibited the growth of roots and total length of rice seedlings in the soil. Anodic electrolyzed water did not affect the growth curve and cell number of marine alga significantly. The anodic electrolyzed water inhibited the browning of potato by inactivating 50% of polyphenol oxidase activity.

• Journal of the Korean institute of surface engineering
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• v.51 no.1
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• pp.1-10
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• 2018

Anodic oxidation treatment of metals is one of typical surface finishing methods which has been used for improving surface appearance, bioactivity, adhesion with paints and the resistances to corrosion and/or abrasion. This article provides fundamental principle, type and characteristics of the anodic oxidation treatment methods, including anodizing method and plasma electrolytic oxidation (PEO) method. The anodic oxidation can form thick oxide films on the metal surface by electrochemical reactions under the application of electric current and voltage between the working electrode and auxiliary electrode. The anodic oxide films are classified into two types of barrier type and porous type. The porous anodic oxide films include a porous anodizing film containing regular pores, nanotubes and PEO films containing irregular pores with different sizes and shapes. Thickness and defect density of the anodic oxide films are important factors which affect the corrosion resistance of metals. The anodic oxide film thickness is limited by how fast ions can migrate through the anodic oxide film. Defect density in the anodic oxide film is dependent upon alloying elements and second-phase particles in the alloys. In this article, the principle and mechanisms of formation and growth of anodic oxide films on metals are described.

• Korean Journal of Materials Research
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• v.12 no.2
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• pp.121-128
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• 2002

Anodic alumina layer can be used as templates for preparation of nano-structured materials, because porous oxide layer on aluminum shows a uniform pore size and a high pore density. In order to find out possibility for template material to prepare nano wire, the effects of the anodic applied potential, anodic time and the temperature of electrolyte on pore diameter of anodic alumina layer were studied using SEM and AFM. The pore diameter of anodic alumina layer increased with applied anodic potential and electrolytic temperature. Especially, the pore diameter of anodic oxide layers formed in chromic acid can be well replicated by widening process in $H_3$$PO_4$solution.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.160-163
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• 2003

This paper describes on anodic bonding characteristics of MLCA(Multi Layer Ceramic Actuator) to Si-wafer using evaporated Pyrex #7740 glass thin-films for MEMS applications. Pyrex #7740 glass thin-films with same properties were deposited on MLCA under optimum RF magneto conditions(Ar 100 %, input power $1\;/cm^2$). After annealing in $450^{\circ}C$ for 1 hr, the anodic bonding of MLCA to Si-wafer was successfully performed at 600 V, $400^{\circ}C$ in - 760 mmHg. Then, the MLCA/Si bonded interface and fabricated Si diaphragm deflection characteristics were analyzed through the actuation test. It is possible to control with accurate deflection of Si diaphragm according to its geometries and its maximum non-linearity is 0.05-008 %FS. Moreover, any damages or separation of MICA/Si bonded interfaces do not occur during actuation test. Therefore, it is expected that anodic bonding technology of MICA/Si wafers could be usefully applied for the fabrication process of high-performance piezoelectric MEMS devices.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.374-375
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• 2006

This paper describes anodic bonding characteristics of MCA to Si-wafer using evaporated Pyrex #7740 glass thin-films for MEMS applications. Pyrex #7740 glass thin-films with the same properties were deposited on MCA under optimum RF sputter conditions (Ar 100 %, input power $1\;W/cm^2$). After annealing at $450^{\circ}C$ for 1 hr, the anodic bonding of MCA to Si-wafer was successfully performed at 600 V, $400^{\circ}C$ in $110^{-6}$ Torr vacuum condition. Then, the MCA/Si bonded interface and fabricated Si diaphragm deflection characteristics were analyzed through the actuation and simulation test. It is possible to control with accurate deflection of Si diaphragm according to its geometries and its maximum non-linearity being 0.05-0.08 %FS. Moreover, any damages or separation of MCNSi bonded interfaces did not occur during actuation test. Therefore, it is expected that anodic bonding technology of MCNSi-wafers could be usefully applied for the fabrication process of high-performance piezoelectric MEMS devices.

• Korean Journal of Materials Research
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• v.12 no.1
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• pp.89-93
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• 2002

To investigate the effect of properties of pores in anodic alumina template(AAT) on the formation and characteristics of metal nano wires, Cu and Ni nano wires were manufactured using anodic alumina template formed in various electrolytes. The characteristics of prepared metal nano wires using AAT could be replicated from those of pores in AAT. The diameters of nano wires could be controlled by the widening process of anodic porous film in $H_3PO_4$ solution. The shape ratio of the nano wire was shown to be $170{\pm}30$ for Ni nano wire formed by AAT made in sulfuric acid.

• Journal of the Korean institute of surface engineering
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• v.43 no.5
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• pp.217-223
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• 2010

For an application as templates of high performance with proper pore size and shape, porous anodic alumina films were prepared by anodization in oxalic acid, and formation behaviors of anodic alumina layer as well as dissolution process in acid solution have been investigated. The surface characteristics on anodic alumina layer were shown to be dependent on the fabrication parameters for anodization. For the dissolution behaviors of anodic alumina, the thickness of the barrier-type alumina layer decreased linearly with the rate of 0.98 nm/min in $H_3PO_4$ solution at $30^{\circ}C$. The changes of the anodic alumina layers were analyzed by SEM and TEM.

• Journal of Dental Rehabilitation and Applied Science
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• v.22 no.4
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• pp.349-365
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• 2006

State of problem : A number of investigation about increase of surface area via various surface treatments and modification of surface constituent have been carried out. Purpose : The surface characteristics and stability of implants treated with anodic oxidation, fluoride ion incorporation, and groups treated with both methods were evaluated. Material and method : Specimens were divided into six groups, group 1 was the control group with machined surface implants, groups 2 and 3 were anodic oxidized implants (group 2 was treated with 1M $H_2SO_4$ and 185V, group 3 was treated with 0.25M $H_2SO_4$ and $H_3PO_4$ and 300V). Groups 4, 5 and 6 were treated with fluoride. Group 4 was machined implants treated with 0.1% HF, and groups 5 and 6 were groups 2 and 3 treated with 10% NaF respectively. Using variable methods, implant surface characteristics were observed, and the implant stability was evaluated on rabbit tibia at 0, 4, 8 and 12 weeks. Result : 1. In comparison of the surface characteristics of anodic oxidized groups, group 2 displayed delicate and uniform oxidation layer with small pore size containing Ti, C, O and showed mainly rutile, but group 3 displayed large pore size and irregular oxidation layer with many crators. 2. In comparison of the surface characteristics of fluoride treated groups 4, 5, 6 and non-fluoride treated groups 1, 2, 3, the configurations were similar but the fluoride treated groups displayed rougher surfaces and composition analysis revealed fluoride in groups 4, 5, 6. 3. The fluoride incorporated anodic oxidized groups showed the highest resonance frequency values and removal torque values, and the values decreased in the order of anodic oxidized groups, fluoride treated group, control group. 4. According to implant stability tests, group 2 and 3 showed significantly higher values than the control group (P<.05). The fluoride treated groups showed relatively higher values than the non fluoride treated groups and there were significant difference between group 4 and group 1 (P<.05). Conclusion : From the results above, it can be considered that the anodic oxidation method is an effective method to increase initial bone stability and osseointegration and fluoride containing implant surfaces enhance new bone formation. Implants containing both of these methods should increase osseointegration, and reduce the healing period.

• Journal of environmental and Sanitary engineering
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• v.13 no.3
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• pp.72-78
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• 1998

For investigation into gas permeation characteristics, the porous alumina membrane with asymmetrical structure, having upper layer with 10 nanometer under of pore diameter and lower layer with 36 nanometer of pore diameter, was prepared by anodic oxidation using DC power supply of constant current mode in an aqueous solution of sulfuric acid. The aluminium plate was pre-treated with thermal oxidation, chemical polishing and electrochemical polishing before anodic oxidation. Because the pore size depended upon the electrolyte, electrolyte concentration, temperature, current density, and so on, the the membranes were prepared by controling the current density, as a very low current density for upper layer of membrane and a high current density for lower layer of membrane. By control of current quantity, the thicknesses of upper layer of membranes were about $6{\;}{\mu}m$ and the total thicknesses of membranes were about $80-90{\;}{\mu}m$. We found that the mechanism of gas permeation depended on model of the Knudsen flow for the membrane prepared at each condition.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2004.11a
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• pp.5-5
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• 2004