Light irradiation provides significant tools for material structuring and processing. In this article, the photo-orientation processes of the organic/inorganic hybrid materials recently achieved in our laboratory are briefly introduced. Irradiation of linearly polarized light to a polymer film containing a photoisomerizabke azobenzene or photocrosslinkable cinnamoyl unit leads to the induction of anisotropic molecular orientations on the surface. This molecular anisotropic surface structure can be transferred to a controlled orientation of nanostructures of organic/inorganic hybrid films at macroscopic scales. Two classes of lyotropic/silica systems have been applied to the photo-orientation procedures, i.e., ordinary surfactant systems and chromonic ones. These processes can be regarded as the extended applications of the so-called command surface systems, which photochemically regulate the molecular orientations of liquid crystals.

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Highly crystalline zinc oxide (ZnO) nanomaterials are synthesized using a seeded growth sol-gel method. In order to control the morphology and the dimensionality of ZnO crystals, a double hydrophilic block copolymer, the Polyacrylic acid-Polyacrylamide (PAA-PAM), was introduced during the growth step. It was shown, first, that depending on the amount of PAA-PAM copolymer, different morphologies of ZnO particles precipitated from homogeneous solutions were obtained, such as ZnO nanostructured spheres or flat hexagonal crystals. Secondly, the dimensionality of ZnO objects grown from seeds on a substrate could be tuned by varying the amount of copolymer leading to ZnO films with variable characteristics. Thus, systematic studies were done in order to investigate the influence of copolymer addition on ZnO nanomaterial morphologies and then explain the mechanisms of the morphological and dimensional modifications.

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The mixed gas of CH₄ (50%) and CO₂ (50%) was fed into the porous compacts of alumina-supported Ni (30 vol%) catalyst heated at 673-973 K. Hydrogen was produced by the reaction of the mixed gas (CH₄+CO₂→2CO+2H₂). A part of produced CO decomposed to CO₂ and C (2CO→CO₂+C) below 873 K. As a parallel reaction, the decomposition of CH₄ occurred in the wide temperature range from 673-973 K. The carbon deposition suppressed the flow of the outlet gas.

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Cisplatin, a drug for the treatment of many kinds of cancer, was investigated to be supported on titanates. Both K₂Ti₄O₉ and its hydrolyzed product H₂Ti₄O₉•H₂O selectively took up its aquoion, cis[Pt(NH₃)₂(H₂O)₂]²⁺, in its aqueous solution with pH=5-9 adjusted with HCl and NaOH. Its captured amounts were 4.93×10^-2 mole for a mole of K₂Ti₄O₉ and 4.73×10^-2 mole for a mole of H₂Ti₄O₉•H₂O, respectively. About a quarter of them was released to the aqueous solution in pH=7.2-7.8 comparable to body fluid. For its magnetic targeting in drug delivery system, magnetite powder was coated with a sol obtained from a mixture of titanium n-butoxide, potassium acetate and acetic acid in ethanol. Its fired product at 600°C was a mixture of magnetic Fe₃O₄ with a cation exchangeable K₂TiO₃. It could uptake the cisplatin aquoion selectively from the diluted aqueous solution in 7.2 ppm concentration.

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Highly conductive and transparent ZnO nanowhisker films which can be used as transparent electrodes of optoelectronic devices have been produced at lower temperatures on modified conductive F-doped SnO₂ coated glass substrates in zinc nitrate-hexamethylenetetramine aqueous solutions with the addition of polyethylenimine. The crystal structure and morphology of ZnO nanowhiskers were characterized by X-ray diffraction and FE-SEM, respectively. The morphology of ZnO whiskers is dependent on the existence of surfactant polyethylenimine. The optical and electrical properties of the resultant porous films are discussed in terms of the crystal characteristics and microstructure. The films consisting of nanowhiskers with a height of 1 μm exhibited high transmittance of up to 85% in the visible range. The high monochromatic incident photo-electric conversion efficiency (IPCE) of about 50% indicated the excellent potential of ZnO electrodes based on nanowhisker arrays.

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β-SiAlON: Eu²⁺ oxynitride green phosphors with compositions of Eu_xSi_6-zAl_zO_zN_8-z (x=0.0065 -0.0390, z=0.231) were successfully prepared using GPS (gas pressured sintering) method. The phase purity, microstructure, luminescent and thermal quenching properties for the prepared β-SiAlON:Eu²⁺ phosphors were investigated in detail. The prepared β-SiAlON:Eu²⁺ phosphor samples with Eu²⁺ doping concentration of x<0.0238 showed pure single β-SiAlON phase. The prepared β-SiAlON: Eu²⁺ phosphors absorbed UV-visible spectral region, and showed a single intense broadband emission in a range from 525 to 540 nm. The effects of the Eu²⁺ doping concentration on the optical properties for the β-SiAlON: Eu²⁺ phosphors were discussed under consideration of concentration quenching. The temperature dependence of photoluminescence (PL) properties was investigated from 25 to 300°C, and the activation energies (ΔE) for thermal quenching of the prepared β-SiAlON:Eu²⁺ phosphors were determined by Arrhenius fitting. The experimental results clearly indicates that the prepared β-SiAlON:Eu²⁺ has great potentials as a down-conversion green phosphor for white light emitting diodes (LEDs) utilizing near UV or blue LEDs as the primary light source.

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Synthesis of well crystallized rod-shaped V₂O₄•2H₂O powders of 100 nm in width in an aqueous solution containing NH₄VO₃ and N₂H₄•H₂O under atmospheric pressure had been investigated. The optimal conditions for atmospherically hot-water treatment at 95°C were found to be as follows: pH 2.5-3.5 and an appropriate amount of N₂H₄•H₂O. How the solution conditions affect the crystal structures and morphologies of the products is discussed. At pH<2.5, no precipitates formed. At pH 4.0-4.5, V₁₀O₂₄•12H₂O would generally be obtained if N₂H₄•H₂O was excessive. It was independent of reduction of NH₄VO₃ solution to tetravalent solids on the dosage of reducing agent N₂H₄•H₂O. The morphologies of the V₂O₄•2H₂O had no obvious relationship with the pH and the dosage of N₂H₄•H₂O. It seems that before treated at 95°C the products were sheet-shaped, and then cleaved along specific crystalline directions after treated, forming rod bunches. The stability of V₂O₄•2H₂O in acid solution and in air was also investigated. The results showed that V₂O₄•2H₂O was unstable in air and could undergo oxidization to be a quasi-amorphous rod-shaped V₁₀O₂₄•12H₂O, especially at high pH, with excessive N₂H₄•H₂O, drying at 150°C in flowing air, and/or being exposed to air for several days.

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Novel liposomal membranes having a metallic surface, so-called metallosomes, were prepared by electroless plating of cationic cerasomes, recently developed as organic-inorganic vesicular nanohybrids. The electroless plating of cerasomes was performed by firstly binding PdCl₄ ^2- ions onto the cationic membrane surface through electrostatic interactions, then subsequently reducing this precursor catalyst to Pd(0), and finally, depositing a layer of metal onto the cerasome surface using an appropriate plating bath. While metallosomes coated with an ultrathin Ni layer could be prepared by electroless Ni plating of cationic cerasomes, it was not possible to derive the corresponding Ni-coated vesicles from the liposomal membranes formed with cationic peptide lipids under similar plating conditions, thus reflecting the difference in the morphological stability of these vesicles. The characterization of the Ni-metallosomes was performed using various physical measurements such as scanning and transmission electron microscopies, energy-dispersive X-ray spectroscopy, electron energy-loss spectroscopy, and electron tomography. The Ni layer thickness was controllable on the nanometer scale by changing the plating time. The gel to liquid-crystalline phase transition behavior of the Ni-metallosomes was observed by differential scanning calorimetry, indicating that the metallosomes maintain their lipid bilayer membranes. Ni-metallosomes with various sizes were prepared from the corresponding cerasomes in a diameter range of 50-5000 nm. Metallosomes with an Au layer were also successfully obtained by electroless Ni/Au substitution plating of Ni-metallosomes.

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The objective of this study is to develop microwave dielectric ceramic thick films with a temperature coefficient of the resonant frequency (T_cf) near to zero. Ba_4.2Sm_9.2Ti₁₈O₅₄ and TiO₂ fine powders are used as main materials to prepare thick films by aerosol deposition (AD) process. In order to evaluate the dielectric properties of thick films in frequency of microwave region, a new measurement procedure based on resonator techniques using a two-port microstrip ring resonator is developed in this study. In this procedure, an electromagnetic field software simulator is used to avoid the complicated calculation that based on experiential formula. The results show the evidences clearly that the T_cf can be modulated by changing the molar ratio of raw powders.

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A commercial alumina nanopowder has been applied to prepare high density alumina ceramic specimens using a simple slip casting method. Slurry preparation process is one of important steps to enhance density and optical property of alumina specimens to be fabricated. In this work, the effect of the amount of ammonium salt of poly(methacrylic) acid dispersant and polyvinyl alcohol binder in alumina suspension on the slurry viscosity was discussed. Green body with relative density higher than 55% could exhibit homogenous appearance when a certain ratio of dispersant to binder is employed. The fully dense translucent alumina compact consisting of submicron grain could be fabricated by atmospheric sintering at 1350°C with soaking time of 3600 s and further HIP-sintering at 1300°C for 7200 s in argon atmosphere.

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ZnO thin films could be fabricated on soda lime glass substrates by sol-gel dip coating method. The thin films fabrication conditions were zinc acetate concentration of 0.10-0.50×10³ mol/m³, withdrawal speed of 0.5-1.5×10^-3 m/s and calcination temperature of 500°C. The film characteristics (roughness, transparency and photoinduced hydrophilicity) were characterized by atomic force microscopy, UV-vis spectrophotoscopy and contact angle analyzer, respectively. It was found that the decreasing withdrawal speed of the coated film using 0.10×10³ mol/m³ zinc precursor could result in a decrease in the film thickness and the film roughness, consequently leading to highly photoinduced hydrophilicity.

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A three-phase composite with SrTiO₃ (STO) ultrafine particles and NiZn ferrite (NZO) ultrafine particles embedded in a polypropylene (PP) matrix was fabricated by using a simple low-temperature hot-pressing technique. The dielectric property and magnetic property of the as-prepared composites were investigated in details, as well as the thermal stability. The results indicate that as the volume of the ceramic fillers is fixed, with the increasing of the ratio of STO phase to NZO phase, the permittivities and dielectric losses of the composites increase while the initial permeabilities and magnetic losses decrease. The cut-off frequencies of the composites are all above 1GHz. Since the low resistivity of NZO, the dielectric losses of the composites are big and decrease with frequency below 100 MHz. Good frequency stability within a wide frequency range has been observed above 100 MHz. For the composite containing 10 vol% STO and 30 vol% NZO, the permittivity, dielectric loss, initial permeability and magnetic loss are 5.7, 0.0025, 2.3 and 0.002 at 100 MHz, respectively. The percolation transition of the composites occurs as the volume fraction of NZO is between 20%-30%. The incorporation of ceramic fillers could improve the thermal stabilities of the composites. Such multifunctional magnetic-dielectric three-phase composites could be used in high-frequency communications for the capacitor-inductor integrating devices such as electromagnetic interference filters.

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Anatase TiO₂ particles consisted of nanocrystals were successfully fabricated in boric acid free aqueous slutions. They showed X-ray diffraction peaks of single phase of anatase TiO₂ and were about 100-200 nm in diameter in scanning electron micrographs. Transmission electron microscopy analysis indicated high crystallinity and unique morphology of the particles. Liquid phase crystal deposition method was improved on the viewpoint of the boric acid free system. The particles can be applied to not only electronic devises, optical devices and photocatalysts, but also cosmetics, food additives and pharmaceutical products.

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The micropore size distribution in TiO₂ particles comprising anatase nanocrystals was evaluated using N₂ adsorption. The solutions containing ammonium hexafluorotitanate and boric acid were kept at 50°C for 30 min. and left to cool for 1 day. The particles comprised nanocrystals of anatase TiO₂ precipitated in the solutions. NLDFT analysis of the adsorption isotherm indicated the existence of pores ~0.7 nm in diameter. These pores caused high BET surface area in the particles (168 m²/g). The unique morphology of these particles with their high volume of micropores and large BET surface area has potential use in many applications.

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ZrB₂-SiC composites were prepared by arc melting using ZrB₂ and β-SiC powders as raw materials and their Vickers micro-hardness, electrical conductivity and thermal conductivity were investigated. The eutectic composition of the ZrB₂-SiC system was ZrB₂-58.5 mol%SiC with a labyrinthine microstructure 100 nm in width and several μm in length. The hardness of the ZrB₂-SiC composites increased with increasing SiC content and showed the highest value of 24 GPa at an indenter load of 4.9 N around the eutectic composition. The ZrB₂-SiC eutectic composite had the highest fracture hardness of 6 MPa m^1/2. The electrical conductivity of ZrB₂-SiC composites ranged from 3.2×10⁴ to 5.0×10⁶ S m^-1 at room temperature and decreased with increasing temperature. Their thermal conductivity at room temperature was 70 to 95 W m^-1 K^-1 and decreased with increasing temperature. The eutectic composite had the lowest thermal conductivity.

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Ta₂O₅ substituted polycrystalline BaTi₂O₅ (BT₂T) was prepared from the raw materials of BaCO₃, TiO₂ and Ta₂O₅ by arc melting on a water-cooled copper plate in the nominal composition of Ba(Ti_1-1.25yTa_y)₂O₅ (y=0 to 0.050). At y< 0.050, the main phase of the obtained specimens was BT₂T which crystallized in a monoclinic cell with (010) orientation perpendicular to the copper plate. The a-axis length and β angle increased from 1.6895 to 1.6916 nm and 103.11° to 103.20°, respectively, and then became almost constant with increasing y from 0 to 0.050. The b- and c-axes lengths were almost constant of 0.3934 and 0.9411 nm, respectively. A peak was observed in the temperature dependence of permittivity for all specimens. The Curie temperature shifted from 750 to 300 K with increasing y from 0 to 0.050. The permittivity of the specimen prepared at y=0.0025 showed the highest value of 3800 at 707 K. Relaxor-like behaviors were observed for the specimens prepared at y>0.025.

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Ba_xSr_1-xRuO₃ (BSRO) thin films were prepared by laser ablation on quartz substrates at a substrate temperature (T_sub) of 973 K and an oxygen pressure (P_O2) of 13 Pa. The effect of Ba substitution for Sr on the microstructure and electrical conductivity (σ) was investigated. (110)-oriented pseudo-cubic BSRO thin films were obtained at a Ba substitution ratio (x) below 0.5. The thin films prepared at x=0.6 to 0.8 had the 4H-type BaRuO₃ (BRO) structure, whereas 9R BRO thin films were obtained at x=1.0. The BSRO thin films consisted of well-crystallized fine grains. The pseudo-cubic lattice parameter of the BSRO thin films increased linearly from 0.393 to 0.407 with increasing x. The BSRO thin films showed metallic conduction, and the σ decreased due to lattice expansion with increasing χ.

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A single crystal of BaLaMnO₄ with I4/mmm has been synthesized by a floating zone method. A new phase of BaLaMnO_4-x was obtained by annealing the single crystal in a reducing atmosphere at 773 K for 168 h. The structural change was analyzed by four-circle X-ray diffractometry (XRD) and transmission electron microscopy (TEM). The new phase has an orthorhombic unit cell (Cccm) of a=0.5504(7) nm, b=0.5502(5) nm, and c=1.3265(1) nm. The structural change from I4/mmm into Cccm was caused by an oxygen deficiency, and a small amount of Mn²⁺ ions was formed by annealing in a reducing atmosphere.

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Periodic Mesoporous Organosilicas (PMOs) have been used as precursors to produce porous Silicon Oxycarbide glasses after pyrolysis at 1000°C in inert atmosphere. Up to now only PMOs with cubic ordering could be successfully converted into an ordered mesoporous SiCO glass. In our work we prepared, under strong acidic media and using an inorganic salt, a PMO with cubic Fm3m phase starting from 1,2-bis(triethoxysilyl)ethane as organosilane and Pluronic^® F127 as templating agent. The as-prepared PMO has been characterized by XRD (Synchrotron beamline), N₂ adsorption/desorption and multinuclear solid state NMR (²⁹Si, ¹³C). After pyrolysis under argon flow the Fm3m phase is retained and the sample still displays a high surface area of 260 m²/g. Further characterizations were performed by ²⁹Si MAS NMR and at 1000°C the product can be described as a true SiCO glass with mixed SiC_xO_4-x units (0≤x≤4).

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The effect of propylene glycol-water ratio on the final particles morphology of Eu doped Y₂O₂S red phosphor prepared by the complex homogeneous precipitation at 95°C and 160°C was examined. The synthesis method was based on hydrolysis of urea and precipitation of the hydroxide in the presence of a glycol under solvothremal conditions; the sulfurization of the powders was carried out at 1000°C in the N₂-H₂S gas. It was found that by changing the glycol concentration one may efficiently control the size of the particles in the range from 60 to 400 nm. The most homogeneous and non-agglomerated powders formed during precipitation at 160°C in the range of glycol-water mass ratios from 1:1 to 3:1. At the same time, the crystallinity determined from the XRD peaks broadening changes in a narrower range of 30-70 nm.

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Novel methods of materials deposition such as inkjet or dispenser can be used to integrate a variety of functional materials, light emitting materials, biomaterials, catalysts, while retaining their original functional activity. Coupled in with the high sensitivity of the quartz crystal microbalance (QCM), the average weight of one drop of deposited material can be monitored. The variations of the frequency changes of the QCM sensor are well correlated with the deposited mass of the droplet of the inkjet as well as dispenser. We are able to predict the dispensing volume with proper calibration of this QCM sensor.

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The synthesis of functional nanostructured powders has been developed through reactive thermal plasma processing. Nanosized particles of titanium oxide powder with high crystallinity and non-equilibrium chemical composition were synthesised by one-step processing based on the oxidation of solid and liquid precursors. Spherical carbon powders were treated in a reactive thermal plasma. Crystallinity, chemical composition, and surface morphology were changed in plasma-treated carbon powders. Plasma-treated carbon powders were used as the anode of a lithium-ion rechargeable battery, and improvements in discharge capacity and efficiency were recognized. The generation of pulse-modulated RF inductively coupled plasmas (PM-ICPs) was developed for the first time. The non-equilibrium states were recognized at the instances of pulse-on and pulse-off, and the concentration of chemically active radical species was increased. This offers a unique physico-chemical condition for materials processing.

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In this work, the microstructure, thermal and electric conductivity properties of near-zero thermal expansion ZrW₂O₈/ZrO₂ and Al₂O₃ added ZrW₂O₈/ZrO₂ composites were studied. Both the two composites exhibit very low thermal conductivity and the thermal conductivity decreases slightly as the temperature increases. The electric conductivity of the two composites increases with the increasing of the measurement temperature. The Al₂O₃ added ZrW₂O₈/ZrO₂ composite has higher thermal and electric conductivity than ZrW₂O₈/ZrO₂ composite. The most important factor which causes the difference of the thermal and electric conductivity of the composites is the porosity.

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We optimized the crystallized phase for imparting high mechanical strength to a composite of MgO-B₂O₃-Al₂O₃ glass and Al₂O₃ filler by hot-press sintering to achieve densification at low temperature and annealing to induce crystallization. The selective crystallization of Al₄B₂O₉ and/or AlBO₃ successfully yielded a composite with high mechanical strength and low porosity. This required the use of a glass with a high Al₂O₃ content that retained its glassy character even when its entire Al₂O₃ content was converted to crystalline Al₄B₂O₉. The composite of MgO-B₂O₃-Al₂O₃ type glass and Al₂O₃ filler exhibited a higher mechanical strength than conventional borosilicate glass and Al₂O₃ filler composites, a porosity of about 1%, a low coefficient of thermal expansion, and was highly waterproof.

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We have investigated the effect of the Ca/P molar ratio in the starting composition on the synthesis of octacalcium phosphate intercalated with dicarboxylate ions (OCPC), starting from calcium carbonate and phosphoric acid in the presence of a dicarboxylic acid, such as succinic acid, adipic acid, or suberic acid. For a Ca/P molar ratio in the starting composition of 1.6, which is the stoichiometric value for OCPC, the highest yield of OCPC with a high degree of crystallinity was obtained for the OCPC samples synthesized with starting Ca/P molar ratios of 1.5, 1.6, and 1.7. The Ca/P molar ratio of the starting composition is an important factor in the synthesis of OCPC. This synthesis route provides for the effective production of OCPC samples.

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A biogas, which contains 60% of methane, 40% of carbon dioxide and a small amount of hydrogen sulfide and ammonia, is a possible fuel of solid oxide fuel cell. Thermal decomposition of 1000 ppm NH₃ in Ar gas was measured over Ni (30 vol%)/Ce_0.8Gd_0.2O_1.9 (GDC) electrode attached to dense GDC electrolyte at 673-1073 K. Pyrolysis of NH₃ started above 773 K and reached 94% at 1073 K. Although N₂ gas was detected in the exhaust gas, H₂ gas was not measured. Furthermore, the oxygen partial pressure of the outlet gas was high. These results are discussed with the properties of GDC mixed conductor (oxide ions and electrons).

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The flexural strength and fracture toughness of 2.8 mol% Y₂O₃-stabilized zirconia polycrystals were investigated. The polycrystals were fabricated by sintering powders prepared by two different methods; the solid phase method (SPM), which involved wet dispersing and mixing using an agitator mill, and the liquid phase precipitation method (LPM). In the case of the LPM sample, the compressive residual stress on the polished surface was lower than of the SPM sample and did not depend on the grain size, while the monoclinic phase fraction on the fracture surface increased with an increase in the grain size. By contrast, for the SPM sample, the compressive residual stress depended on the grain size, and the monoclinic phase fraction on the fracture surface revealed the tendency to decrease with an increase in the grain size. The flexural strength and fracture toughness of the LPM sample were greatly influenced by the stress-induced transformation. However, mechanical properties and transformation behavior of the SPM sample in relation to grain size implied that the SPM sample was dominated not only by the stress-induced transformation but also by the compressive residual stress and the microcracks generated by the transformation. For both SPM and LPM samples, the relationship between the transformed volume V_f√h, where V_f is the tetragonal phase fraction and h is the transformed depth, and the fracture toughness was linear. The fracture toughness for the SPM sample was more strongly influenced by V_f√h than that of the LPM sample.

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To simultaneously vitrify Ion Exchange Resin, Zeolite, and Dry Active Waste generated from Korean Nuclear Power Plant, a borosilicate glass system was formulated. Viscosity and electrical conductivity of the glass were measured and within the desired ranges at the processing temperature. Those activation energies were evaluated as 152 and 70.46 kJ/mol within a temperature range of 1223 to 1623 K, respectively. Time-Temperature-Transformation study was performed using data from heat treatment. The hematite crystal was found within a temperature range of 823 to 1123 K. Mössbauer spectroscopy showed about 42% Fe²⁺ state existed in the glass produced from operation of the pilot-scale plant. Product Consistency Test performed from 7 to 120 d in the glass showed the leach rates of B, Na, Li and Si were much less than those of the benchmark glass. International Organization for Standardization test was performed at 363 K for 1022 d and shown that Cumulative Fraction Leached values of Na, Li, and Si were saturated below the fraction of 0.4 except that the leaching of B increases continuously. About 50 μm thickness layer was observed to be as a protective layer against continuous corrosion. According to Vapor Hydration Test, the corrosion rate of the glass was 2 g/m²/d and met the specification (50 g/m²/d). Based on Soxhlet leaching accomplished at 371 K for 30 d, the weight loss of the glass was determined as 106.8 g/m² which was lower than those of other HLW (High-Level radioactive Waste) glasses.

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Synthesis of aluminum substituted tobermorite from blast furnace slag was attempted. Mixture of blast furnace slag and quartz controlled Ca/(Al+Si) ratio for 0.8 to 1.0 was treated by a rotary hydrothermal treatment for 24 h at 453 K. Obtained samples were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM) observation. Monolithic tobermorite was successfully synthesized with 0.8 of Ca/(Al+Si) ratio by this rotary hydrothermal treatment, whereas monolithic tobermorite could not be synthesized by the conventional static hydrothermal treatments, leading to the mixture of tobermorite and other calcium silicate containing unreacted SiO₂. Pb removal ability was investigated for this monolithic tobermorite obtained by this rotary hydrothermal method from blast furnace slag. It was found that monolithic tobermorite had a good Pb removal ability. This result shows that the synthesis of tobermorite is useful as a recycle of blast furnace slag.

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The alumina cryogel with 5 mass% platinum was prepared from aluminum sec-butoxide and H₂PtCl₆ through the sol-gel processing and subsequent freeze drying. The cryogel showed higher thermal stability of platinum than the corresponding xerogel and impregnation catalysts at elevated temperatures. Also for the catalytic VOC combustion the cryogel exhibited higher activity than other catalysts. It was revealed that about half of the platinum surface was inside the alumina cryogel, and such encapsulation was considered the principal cause for the higher stability.

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One of author's affiliations was omitted. Erased affiliation name is Dankook University, which stands for the third affiliation. Wrong:Department of Biomaterials Science & Institute of Tissue Regeneration Engineering, School of Dentistry
Right:Department of Biomaterials Science &: Institute of Tissue Regeneration Engineering, School of Dentistry, Dankook University

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