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Production of proteins in secretary form is one of the important factors affecting fermentation. The Tat (twin arginine translocation) protein secretion system, which includes the proteins TatA, TatB, and TatC, was identified in the genomic sequence of Streptomyces griseus IFO13350. The tatA and tatC genes were organized into a polycistronic operon, whereas tatB was located separately on the chromosome. Comparison of amino acid sequences suggested that TatC was a membrane-spanning protein, whereas TatA and TatB were found to be cytoplasmic proteins. Analysis of extracellular proteins and N-terminal amino acid sequencing revealed that secretion of SGR5556 was significantly enhanced by overexpression of TatAC in S. griseus HH1. Further, enzymatic study showed that SGR5556 encoded a glycerophosphoryl diester phosphodiesterase. In addition, other hydrolase activities, such as those of amylase, total protease, metalloprotease, trypsin, chymotrypsin, and Leuaminopeptidase, were also enhanced by 3, 3, 2.6, 2.3, 5.4, and 2.5 fold, respectively, in S. griseus upon TatAC overexpression. Overexpression of TatAC induced the production of a greenish-yellow pigment in S. griseus HH1 as well as more abundant sporulation at an earlier stage in Streptomyces coelicolor A3(2). In silico analysis by TatFIND, SignalP, and TMHMM identified 19 binding proteins, 28 enzymatic proteins, and 27 other proteins with unknown functions as putative TatAC-dependent secretary proteins. These results clearly indicate that TatA and TatC constitute a functional Tat system in S. griseus. Additionally, the S. griseus Tat system can be useful for the production of valuable proteins, including many hydrolytic enzymes and candidates of Tat-dependent secretary proteins, under industrial conditions.

Among LTCC material for substrate, the crystallized anorthite system was mainly studied as high strength material. However, specific factors that have affected on strength of material were studied insufficiently on anorthite system. In this study, the composition of anorthite glass was Ca-Al-Si-Zn-O. The changes of phase and microstructure were observed with the amount and the particle size of glass and the sintering temperature. It was studied that the factors affected on the strength of material. Phases of anorthite and were formed with the increase of sintering temperature. The phase was increased with amount, acted as filler, and the strength of material is increased with phase. But phases of anorthite and didn`t affect on the strength of material. In the case of 60 vol% glass amounts and below of glass particle size, the strength of material was decreased. It is thought that the decrease of strength was due to non-homogeneous mixing between glass powder and filler.

The purpose of this study was to investigate the effects of Microcomputer Based Laboratory (MBL) on the middle school students` graphing skill and science process skill in Earth Science classes. MBL teaching materials for inquiry-based instructions were developed to teach five experimental topics related to the middle school `Earth Science.` Thirty three middles school students participated in this study, and the pre- and post-tests were conducted. Results indicated as follow: First, MBL classes were effective in developing the graphing skill of middle school students. They were efficient both in graph construction and graph interpretation, especially in data transformation. Second, MBL classes were effective in helping participants to use science process skills, especially, in the subordinate areas including formulating hypotheses, making operational definition, graphing, and interpreting data.

Low-temperature fabrication of Al2O3-PTFE (poly tetra fluoro ethylene) composite thick films for flexible integrated substrates was attempted by using the aerosol deposition method. For optimization of composite thick films, a novel calculation method for the ceramic contents in the composites was a...

A solid oxide fuel cell (SOFC) with high specific electrolyte surface area was fabricated using the multi-pass extrusion process. The cell configuration was NiO-YSZ/YSZ/LSM. In this design, one tube contained 7 individual fuel cells. The outer diameter of the tube was 5 mm and 4.1–4.2 mm after extrusion and sintering, respectively. The length of the cell was optimized to 3–5 cm with continuous channels of 400–450 μm in diameter. The porous microstructures of the anode and the cathode and the dense microstructure of the electrolyte were observed by scanning electron microscopy. The relative density of the electrolyte was >96% and the thickness was 15–20 μm. The XRD profiles indicated no undesirable phases after co-sintering at 1300 °C.

This study was designed to evaluate changes in the terpene composition of 3 types of pines (Pinus densiflora, Pinus thunbergii and Pinus rigida), while decomposing their leaf litter. Needle litters were placed at two different organic layer depths, one on the surface and the other beneath the litter layer. Changes in the terpene composition of this litter were detected using a gas chromatograph-mass spectrometer. Among the monoterpenes acquired from the fresh needles of P. densiflora and P. rigida, α-pinene (12.05% and 19.87%, respectively) was the major one, followed by β-pinene (2.90% and 14.07%). However, from the needles of P. thunbergii, β-pinene (20.77%) was the major one, followed by α-pinene (10.79%). Among the sesquiterpenes detected in P. densiflora , trans-caryophyllene (3.12%) was the highest composition compound, whereas germacrene-D (6.09%) for P. thunbergii and 1,6-cyclodecadiene (7.41%) and endo-1-bourbonanol (7.41%) for P. rigida were the highest content compounds. However, the total amounts of terpenes decreased sharply by 40-85.4% in all three types of pine needle after 90-120 days of the experiment. The concentration of each terpene differed during decomposition, and the majority of compounds disappeared from beneath the litter layer. It was determined that three types of reducing patterns of each compound appeared on the rate of loss of concentration during decomposition; one pattern decreasing sharply during the initial period, another pattern steadily or slowly decreasing, and a newly detected pattern at low concentration occurring during decomposition.

The purpose of culvert design is to determine optimum size for a safe drainage of flood discharge. The present method of culvert design in Korea is generally carried out by using "Road Drainage Design" of Korea Expressway Corporation (1991), which is based on the manual of Federal Highway Association (FHWA) of USA. However, this method may result in subjective error because of using graphs and the usage of nomograph can be a major obstacle for computer modelling. Some errors found in the previous works of culvert design are corrected, and a new logic has been developed for a simple determination of culvert size in this study. FHWA (1985) presents a nomograph to determine the critical water depth and the velocity head for a circular pipe, but in this study simple explicit equations have been developed to determine both respectively.

Biomimetic whisker-like apatite was formed on thermally and NaOH-treated titanium powder in a simulated body fluid (SBF). In the early process of the SBF immersion, the surface structure of the titanium powder was loosened, possibly due to the dissolution of Na? ions on the surface of the titanium powder into SBF. When immersed for 7 days in SBF, fine precipitates appeared on the titanium surfaces; the coating layer (＜200 ㎚ in thickness) consisted of nanostructured, amorphous whisker-like and particulate phase, observed by TEM. With the extension of the immersion time to 16 days, the chrysanthemum flower type morphology of carbonated hydroxyapatite with a nanocrystallinity was developed on the surface of the titanium powder.

Bi 6 Ti 5 TeO 22 (BTT) thin films were grown on a Pt/Ti/SiO 2 /Si(1 0 0) substrate under various conditions and the valence state of the Te ion was investigated. For the BTT films grown at 300 °C, most of the Te ions existed as Te 4+ ions. However, for the 10 mol% Mn-added BTT films grown at 300 °C, Te 6+ ions were found even in the film grown under low oxygen partial pressure (OPP) and their number increased with increasing OPP. This increase was attributed to the presence of Mn 2+ ions, which assisted the transition of Te 4+ ions to Te 6+ ions in order to maintain the charge balance of the Ti 4+ sites. Furthermore, in the films grown at 300 °C under a high OPP of 80.0 Pa and subsequently annealed at 600 °C under a high oxygen pressure of 101 kPa, most of the Te ions existed as Te 6+ ions. However, for the film grown at 300 °C under low OPP, even though the film was annealed under a high oxygen pressure of 101 kPa, only a few of Te 6+ ions were formed, whereas most of Te ions remained as the Te 4+ ions.

Low-temperature nitridation was used to form a protective and conductive layer on stainless steel. The surface characterization reveals that a continuous and protective Cr-nitride/oxide layer (CrN and Cr2O3) forms on the 446M stainless steel surface after low-temperature nitridation. The electrical conductivity of the sample is investigated in terms of the interfacial contact resistance. This value for nitrided 446M at low temperature is 6 mΩ cm2, which is much lower than that of the bare 446M stainless steel (about 77 mΩ cm2) at a compaction force of 140 N/cm2. The corrosion resistance of low-temperature nitrided 446M stainless steel is examined in potentiodynamic and potentiostatic tests under simulated polymer electrolyte membrane fuel cell (PEMFC) conditions with pH 3 H2SO4 at 80 °C. In a simulated anode condition, the current density is −1 × 10−6 A/cm2. In a simulated cathode condition, the current density is 1 × 10−7 A/cm2. Low-temperature nitrided 446M stainless steel shows superior electrical conductivity and corrosion resistance than bare 446M stainless steel.

The effect of oxygen partial pressure (OPP) on the leakage current density of Bi 5 Nb 3 O 15 (B 5 N 3 ) films grown on Pt electrodes was investigated. The leakage current density was very high for the film grown under a low OPP of 1.7 mTorr, but was significantly reduced by the subsequent annealing under a high oxygen pressure or for the film grown under high OPP of 5.1 mTorr. The variation of the leakage current density with OPP was explained by the number of oxygen vacancies, which produced electron trap sites at the interface between the Pt electrode and the B 5 N 3 film. Schottky emission was postulated as the leakage current mechanism of the B 5 N 3 films. The barrier height between the Pt electrode and the B 5 N 3 film grown under a high OPP of 5.1 mTorr was approximately 1.55 eV, but decreased to 0.81 eV for the film grown under a low OPP of 1.7 mTorr due to the presence of the oxygen vacancy.

This paper introduces a case where IT services played a critical role as a business enabler with a novel business model. Three companies such as Coca-Cola, Samsung Electronics, and Samsung SDS successfully made a joint effort to develop a new digitized vending machine with information services for 2008 Summer Olympics in Beijing. Each vending machine was equipped with a LCD TV. People could watch Olympic Games in real-time or find transportation schedules, road maps, and weather information while drinking soda. Through this service, three companies were able to fulfill the sponsorship of the Olympics and learned critical lessons that could be transferred to other businesses.

In this study, we investigated the effects of Cr dopant (1.0 at% sintered at for 1 h in air) on the bulk trap (i.e. defect) and interface state levels of ZnO using dielectric functions (, , , , and ), admittance spectroscopy (AS), and impedance-modulus spectroscopy (IS & MS). For the identification of the bulk trap levels, we examine the zero-biased admittance spectroscopy and dielectric functions as a function of frequency and temperature. Impedance and electric modulus spectroscopy is a powerful technique to characterize grain boundaries of electronic ceramic materials as well. As a result, three kinds of bulk defect trap levels were found below the conduction band edge of ZnO in 1.0 at% Cr-doped ZnO (Cr-ZnO) as 0.11 eV, 0.21 eV, and 0.31 eV. The overlapped defect levels ( and ) in admittance spectra were successfully separated by the combination of dielectric function such as , , and . In Cr-ZnO, the interfacial state level was about 1.17 eV by IS and MS. Also we measured the resistance () and capacitance () of grain boundaries with temperature using impedance-modulus spectroscopy. It have discussed about the stability and homogeneity of grain boundaries using distribution parameter () simulated with the Z"-logf plots with temperature.

The present study aims at the examination of the effects of 1 mol% NiO addition on the reaction, microstructure development, resultant electrical properties, and especially the bulk trap and interface state levels of (Sb/Bi

Dolomite-type borate ceramics consisting of CaZrB2O6 were synthesized via a conventional solid-state reaction route; low-temperature sintering was explored using Bi2O3–CuO additives of 1–7 wt% for low-temperature co-fired ceramics applications. For several sintering temperatures, the microwave dielectric properties and chemical resistance of the ceramics were investigated. The CaZrB2O6 ceramics with 3 wt% Bi2O3–CuO addition could be sintered below 925°C, and the microwave dielectric properties of the low-temperature samples were ɛr=10.55, Q×f=87,350 GHz, and τf=+2 ppm/°C. The chemical resistance test result showed that both CaZrB2O6- and Bi2O3–CuO-added CaZrB2O6 ceramics were durable in basic solution but were degraded in acid solution.

Mn-doped Bi4Ti3O12 (M-B4T3) films were well formed on a TiN/SiO2/Si substrate at 200degC without buckling using RF magnetron sputtering. The leakage current density of these films was considerably influenced by the oxygen partial pressure (OPP), which was attributed to the presence of oxygen vacancies or oxygen interstitial ions. The film grown under 2.8-mtorr OPP showed the lowest leakage current density. The M-B4T3 films grown at 200degC showed a high dielectric constant of 38 with a low loss in both kilohertz and gigahertz ranges. The 39-nm-thick film showed a high capacitance density of 8.47 fF/mum2 at 100 kHz, and its temperature and quadratic voltage coefficients of capacitance were low at approximately 370 ppm/degC and 667 ppm/V2, respectively, with a low leakage current density of 7.8 times 10-8 A/cm2 at 2 V. Therefore, the M-B4T3 thin film grown on a TiN/SiO2/Si substrate is a good candidate material for high performance, radio frequency metal-insulator-metal capacitors.

The experimental particle samples included (Mn 0.1 Fe 0.9 )O·Fe 2 O 3 and FeO·(Gd 0.1 Fe 0.9 ) 2 O 3 with Mn 2+ and Gd 3+ substitutions in inverse spinel Fe 3 0 4 . A lecithin surfactant was adsorbed onto the magnetic particles by ultrasonication. The samples prepared showed excellent dispersibility at the mean size of 13 nm; their saturation magnetization values were 63 emu/g for the bare and Mn-substituted magnetites, and 56 emu/g for the Gd-substituted magnetite. The crystal structure of the substituted magnetites was very similar to that of the bare magnetite, due to a small amount of 0.1 mole fraction substituted in synthesizing the magnetite. The magnetite fluids, according to T2-weighted MR images, effectively diminished the signal intensity in the liver and spleen of Sprague-Dawley rats.

Low temperature co-fired ceramic (LTCC) process combined with thick film photolithography was employed to fabricate ceramic-based microfluidic devices. To check the applicability of novel process, three types of passive mixers, diffusion-driven T-type mixers with different channel width and convection-driven chaotic mixer, were fabricated and their microfluidic performance was evaluated. It was confirmed that the degree of mixing in ceramic-based microfluidic passive mixers was well matched with the numerical simulation data.

While the stress response to heat and exercise is limited in the heart with progressive aging, recent data indicate that acute or short-term exercise upregulates the Mn isoform of superoxide dismutase (MnSOD), which may provide protection against ischemia-reperfusion injury and cell death by reducing oxidative stress. Growing evidence indicates that inducible nitric oxide synthase (iNOS) contributes to age-induced increases in oxidative stress and risk of heart failure. We postulated that oxidative stress and iNOS levels would be related to the ability of the aging heart to upregulate MnSOD in response to long-term exercise training. Six- and twenty-seven-mo-old Fischer-344 rats had been assigned to young sedentary (YS), young exercise (YE), old sedentary (OS), or old exercise (OE) groups. ET groups ran on a treadmill for 60 min/day, 5 days/wk for a total of 12 wk. MnSOD protein expression in the left ventricle was increased (+43%) by 12 wk of exercise training in the old age group, with no changes in Cu,ZnSOD. Exercise training also increased MnSOD activity in left ventricles from old and young rats. HSP70 was inducible by exercise training in hearts exclusively from the young age group. iNOS protein expression increased markedly with aging (+548%), while exercise training decreased iNOS levels by −73% in OE compared with OS. In addition, 4-hydroxynonenal protein adducts in the left ventricle increased by 237% with aging, while 12 wk of exercise training resulted in attenuation (−55%). These data indicate that inducibility of MnSOD is preserved with long-term exercise training in the aging rat heart. Moreover, upregulation of MnSOD in the aging heart was directly associated with attenuated levels of oxidative stress, including iNOS.

An amorphous Bi 4 Ti 3 O 12 phase was formed when films were grown at 2 Ti 2 O 7 and Bi 2 Ti 4 O 11 transient phases were developed when films were grown at 400–500 and 600 °C, respectively. A homogeneous Bi 4 Ti 3 O 12 crystalline phase was formed in the film grown at 700 °C. The high leakage current density (5 × 10 −7 A cm −2 at 0.2 MV cm −1 ) of the film grown at 300 °C under 100 mTorr oxygen partial pressure (OPP) decreased to 2 × 10 −8 A cm −2 for the film grown at 200 mTorr OPP, due to the decreased number of intrinsic oxygen vacancies. However, when OPP exceeded 200 mTorr, the electrical properties were deteriorated due to the formation of oxygen interstitial ions. Mn-doping at a suitable level improved the electrical properties of the films by producing extrinsic oxygen vacancies that reduced the number of intrinsic oxygen vacancies. Schottky emission was suggested as the leakage current mechanism of the Bi 4 Ti 3 O 12 film.

We have successfully fabricated the alumina thick films using inkjet printing processes without a high temperature sintering process. Alumina suspension as dielectric ink was formulated by combining nano-sized alumina powders with an anionic polymer dispersant in formamide/water as co-solvent. The thickness of the printed alumina thick film was measured at around 5 um by field emission scanning electron microscope. The calculated packing density of 68.5 % from the printed alumina thick film was much higher than the same films fabricated by conventional casting or dip coating processes. Q factor of the dielectrics thick film infiltrated with cyanate ester resin was evaluated by impedance analyzer.

We investigated the sintering and electric properties of ZnO-1.0 at% (ZT1) and 1.0 at% Mn-doped ZT1(ZT1M1) system. itself melts at in air but forms the or phase with ZnO as increasing temperature and therefore retards the densification of ZnO to . In ZT1M1 system, also, the densification of ZnO was retarded up to and then reached > 90% of theoretical density above . It was found that a good varistor characteristics(nonlinear coefficient ) were developed in ZT1M1 system sintered at due to Mn which known as improving the nonlinearity of ZnO varistors. The results of C-V characteristics such as barrier height (), donor density (), depletion layer (W), and interface state density () in ZT1M1 ceramics were , 1.6 V, 93 nm, and , respectively. Also we measured the resistance and capacitance of grain boundaries with temperature using impedance and electric modulus spectroscopy. It will be discussed about the stability and homogeneity of grain boundaries using distribution parameter () simulated with the Z(T)"-logf plots.

The condition for the occurrence of extra current peak near 3.7 ∼ 3.9 V in CV and the relationship between the intensity of the extra current peak and the volume of phase transformation from tetragonal to cubic phase was investigated using in situ bending beam method. It was found that the extra current peak evolved when the sample was subject to the 3 V range and its intensity increased as the excursion depth to the 3 V range was increased. The in situ bending beam method data revealed that the extra current peak accompanied the tensile strain variation which is due to the phase transformation of a residual tetragonal phase to a cubic phase. Further, it was found that the amount of the phase transformation increased as the excursion depth to the 3 V range increased, i.e. the volume of the phase transformation was proportional to the intensity of the extra current peak. It seems that the phase transformation from tetragonal phase to cubic phase cannot be completed during the voltage sweep at the 3 V peak. On the contrary, the voltage excursions to 4 V range did not affect the evolution of the extra current peak. Keywords: LiMn2O4, Extra current peak, Phase transformation, In situ bending beam method, Lithium secondary batteries

In order to investigate the potential cytotoxic effects of particle-induced x-ray emission (PIXE) on tumor cells, 45 MeV proton beam was irradiated on C6 glioma cell lines that had taken up alginate-coated ferrite nanoparticles (Alg-SNP). Cells were anchored in vertical 96-well dishes facing a horizontal beam where the Bragg peak was placed on the upper part of the 96-well dish. Experimental groups included cells without SNP as a control (No-SNP), and cells incubated with SNP for 6 hours (6hr-SNP) or overnight (ON-SNP). A 0 to 200 Gy proton beam from an MC50 cyclotron (Scanditronix, Sweden) at the Korea Cancer Center Hospital (Seoul, Korea) was used to irradiate each experimental group. Perinuclear Alg-SNP nanoparticle distribution was observed in glioma cells. The test groups (6hr-SNP or ON-SNP) showed an estimated 20-28% (ANOVA, P < 0.05) less cell survival compared to the control group based on MTT assay. Nuclear damage, indicating apoptosis, was present at a higher frequency in the 6hr-SNP and ON-SNP groups up to relatively low radiation dose of 100 Gy by fluorescence microscopy upon Hoechst 33342 and Acridine Orange staining. Ferrite nanoparticles alone were not cytotoxic at the experimental concentration of 0.15 mg/ml. Therefore ferrite nanoparticles may induce additional cytotoxicity from X-ray emission from potential PIXE effects. PIXE and metal nanoparticles may be developed as a therapeutic factor and prodrug for localized proton beam therapy without side effects of solid or disseminate tumors on the surrounding normal tissue.

Microfluidic device can be applied in a wide range of chemical and biological technology. In this paper, ceramic-based T-type passive mixers for microfluidic applications were fabricated by LTCC process combined with thick film photolithography. The base ceramic material in thick film was amorphous cordierite ((Mg,Ca)₂Al₄Si?O 18 ) and photoimageable polymers were added to give a photosensitivity. Two types of passive mixer, which showed the channel width of 1.0 mm and 200 μm, respectively, were designed considering mixing efficiency in the channel and their microfluidic properties were discussed in detail.

In this study, it has been investigated on the changing behavior of electrical properties in (Sb/Bi

Seasonal variations in the chemical composition of leaves fromAgastache rugosa were analyzed by gas chromatography-mass spectrometry (GC-MS). Phytotoxic and antimicrobial activities of its essential oil were investigated by characterizing 31 components, primarily methylchavicol (80.24%),dl-limonene (3.50%), linalool (4.23%), 5-methyl-2-(1-methylethylidene)-cyclohexanone (3.84%), and β-caryophyllene (2.39%). The contents of most of these chemical constituents varied significantly (P

In this work, Ga-doped ZnO (GZO) thin films for gas sensor application were deposited on low temperature co-fired ceramics (LTCC) substrates, by RF magnetron sputtering method. The LTCC substrate is one of promising materials for this application since it has many advantages (e.g., low cost production, high manufacturing yields and easy realizing 3D structure etc.). The LTCC substrates with thickness of were fabricated by laminating 12 green tapes which consist of alumina and glass particle in an organic binder. The structural properties of the fabricated GZO thin film with thickness of 50 nm is analyzed by X-ray diffraction method (XRD) and field emission scanning electron microscope (FESEM). The film shows good adhesion to the substrate. The GZO gas sensors are tested by gas measurement system and show fast response and recovery characteristics to gas that is 27.2 and 27.9 sec, recpectively.

Though need for precise alignment of interlayer patterning in LTCC application, there have been few reports about zero-shrinkage sintering techniques. In this study, ceramic substrate with minimal x–y shrinkage was prepared by glass infiltration method with ‘Al2O3/glass/Al2O3’ structure. Glass infiltration into alumina particle layer was observed with variation of both sintering temperature (700 ≤ T sint. ≤ 900 °C) and alumina particle size distribution (0.5 ≤ D 50 ≤ 1.8 μm). Since glass had low viscosity enough to infiltrate at 700 °C, infiltration started at that temperature and infiltrated up to 20 μm or so with temperature increase, but infiltration depth did not increase noticeably above 750 °C. Based on these results, when sintered at 900 °C with controlled sheet thickness of both glass and alumina, the shrinkage in x–y direction was calculated as less than 0.2%, with 40% in z direction. Dielectric constant (ɛ r) measured 6.19 with quality factor (Q) of 552 at 1 GHz of frequency. From these results, it is thought that zero-shrinkage ceramic substrates would be obtained without de-lamination.

Laminated LTCC components of high integrity, fabricated by thick film process, are applied to industrial field of IT technology along with miniaturization trend of electronic devices. Dispersion states were examined by several evaluation methods with MLS-22, which is one of commercial LTCC powders, to achieve optimal dispersion as basis for stable LTCC fabrication process. Slurry viscosity, surface roughness of dip-coated slide glass, sedimentaion of slurry, and SEM observation of dried surface were utilized with respective amount change of various commercial dispersants. Among these commercial dispersants, optimal dispersion state was obtained with 0.4 wt% of BYK-111, from the results of various evaluation methods.

Muscle atrophy is a highly prevalent condition among older adults, and results from reduced muscle mass and fiber cross-sectional area. Resistive exercise training and moderate (30-40%) caloric restriction may reduce the rate of sarcopenia in animal models. We tested the hypothesis that lifelong, voluntary exercise combined with mild (8%) caloric restriction would attenuate the reduction of muscle fiber cross-sectional area in the rat plantaris. Fischer-344 rats were divided into: young adults (6 mo) fed ad libitum (YAL); 24 mo old fed ad libitum (OAL); 24 mo old on 8% caloric restriction (OCR); lifelong wheel running with 8% CR (OExCR). Plantaris fiber cross-sectional area was significantly lower in OAL than YAL (-27%), but protected in OCR and OExCR, while mass/body mass ratio was preserved in OExCR only. Furthermore, 8% CR and lifelong wheel running attenuated the age-induced increases in extramyocyte space and connective tissue. Citrate synthase activity decreased with age, but was not significantly protected in OCR and OExCR. Total hydroperoxides were higher in OAL than YAL, but were not elevated in OExCR, with out a change in MnSOD. IGF-1 levels were lower in OAL (-57%) than YAL, but partially protected in the OExCR group (+51%).

Two types of frits with different compositions were used to develop a high strength substrate in electronic packaging using a low temperature co-fired ceramic process. In order to reveal the crystallization stage during heating to approximately 900 °C, a glass–ceramic consisting of the two types of frits, which had been crystallized to diopside and anorthite after firing, was tested at different mixing ratios of the frits. The exothermal peaks deconvoluted by a Gauss function in the differential thermal analysis curves were used to determine the onset point of crystallization of diopside or anorthite. The onset points of crystallization were affected by the mixing ratio of the frits, and the microstructure of the glass–ceramic depended on the onset point of crystallization. It was found that when multicrystalline phases appear in the microstructure, the resulting complex microstructure could be predicted from the onset point of crystallization obtained by differential thermal analysis.

B2O3 was added to nominal composition Zn1.8SiO3.8 (ZS) ceramics to decrease their sintering temperature for application to low-temperature cofired ceramic (LTCC) devices. B2O3 reacted with SiO2 to form a liquid phase containing SiO2 and B2O3. The composition and melting temperature of the liquid phase depended on the sintering temperature and the B2O3 content. The specimen containing 20.0 mol% of B2O3 sintered at 900°C exhibited high microwave dielectric properties of Q×f=53 000 GHz, ɛr=5.7, and τf=−16 ppm/°C, confirming the promising potential of the B2O3-added ZS ceramics as candidate materials for the LTCC devices.

Using a common electroless bath, Ni-8YSZ (Ni-8 mol% yttria stabilized zirconia) composite nano powder have been synthesized without use of any expensive sensitizing agent. HRTEM micrographs indicated that the coating morphology of Ni nano particles on the 8YSZ showed a spotty, discontinuous distribution and the Ni nano particles appeared as a crystalline phase. The amount of Ni in the composite powders was varied from 36–51 wt.% by changing the substrate powder loading in the electroless bath. Bar type samples were prepared by uniaxial pressing and sintering at 1300 °C for 2 h with these coated powders. The cubic (c)-zirconia was found to partially dissociate into monoclinic (m)-zirconia on sintering with Ni content 41% or higher and also increases with the increase of Ni content. The microstructure of each Ni-YSZ cermet after reduction in a H 2 + Ar gas atmosphere showed dual scale porosity (micro and submicron porosity). The Ni-8YSZ cermet samples showed metallic electrical conduction behavior, proving the percolation capability of the synthesized nano composite.

Recently, there has been growing interest in low loss and low dielectric constant material for LTCC application, as the frequency range for electronic devices increases. This study was designed to evaluate the effect of cordierite filler for low dielectric constant LTCC material. From the previous experiments, two glass compositions of B-Si-Al-Zn-Ba-Ca-O and B-Si-Al-Sr-Ca-O system, were chosen. Each powder of two glass compositions was sintered respectively with commercial cordierite powder in temperature range from . Crystalline cordierite and glass peaks were affected only with two factors of composition and sintering temperature among various factors. With the optimized condition of two cordierite/glass compositions, obtained dielectric constant was below 5.5 and quality factor was above 1,000. Closed pore of sintered body was controled by sintering temperature and sintering time. When cordierite/glass composite with ratio of 5.5:4.5 was sintered at , densification was sufficient with good dielectric characteristics of ${\epsilon}_r

Several studies are reported on the possibility of reliable bonding alumina and barium titanate with derivation from the glass infiltration method for zero-shrinkage substrates, but infiltration into alumina was not satisfactory, compared with the case of barium titanate. In this study, silicon radical, which is main component of glass, is coated on alumina powder in order to improve glass infiltration effect in bonding alumina and barium titanate with use of common glass in low temperature cofired ceramic composite. As a result, it is verified that infiltration effect on large-sized alumina powder layer was improved to the level of barium titanate which is fully glass infiltrated and bonding barium titanate and alumina was possible.

We investigated the influence of the growth season of Artemisia princeps var. orientalis (P AMPAN .) H ARA on antimicrobial and antioxidative activities. The ethyl acetate and water fractions of crude methanol extract from the plant collected monthly (April through October) were tested against three gram-positive, two gram-negative bacteria and one lactic acid bacterium. The ethyl acetate and water fractions of crude methanol extract from A. princeps var. orientalis collected in August and September had the highest antimicrobial activity. The antimicrobial activity of extract from A. princeps var. orientalis for Lactobacillus plantarum was not found at any concentration and in any growth season. Minimum inhibitory concentration (MIC) for each strain by ethyl acetate fraction of methanol extract from A. princeps var. orientalis was different depending on the tested strain and growth season of the plant. MIC for each strain was the highest in the sample from April, followed by October. The antioxidative activities of methanol extracts from A. princeps var. orientalis collected monthly were measured by their scavenging activity on free radical of 1,1-diphenyl-2-picrylhydrazyl (DPPH) and xanthine oxidase (XO) inhibitory activity. The DPPH radical scavenging activities of the extracts from the plants collected in May, June and July were higher than any other. The XO inhibitory activities of the extracts of A. princeps var. orientalis collected in April and May showed the greatest activity, it is different with antimicrobial activity. This is the first report that antimicrobial and antioxidative activity of the extracts of A. princeps var. orientalis is different with growth season.

Lots of integration work has been done in order to miniaturize the devices for communication. To do this work, one of key work is to get miniaturized inductor with high Q factor for RF circuitry. However, it is not easy to get high Q inductor with silicon based substrate in the range of GHz. Although silicon is well known for its good electrical and mechanical characteristics, silicon has many losses due to small resistivity and high permittivity in the range of high frequency. MEMS technology is a key technology to fabricate miniaturized devices and LTCC is one of good substrate materials in the range of high frequency due to its characteristics of high resistivity and low permittivity. Therefore, we proposed and studied to fabricate and analyze the inductor on the LTCC substrate with MEMS fabrication technology as the one of solutions to overcome this problem. We succeeded in fabricating and characterizing the high Q inductor on the LTCC substrate and then compared and analyzed the results of this inductor with that on a silicon and a glass substrate. The inductor on the LTCC substrate has larger Q factor value and inductance value than that on a silicon and a glass substrate. The values of Q factor with the LTCC substrate are 12 at 3 GHz, 33 at 6 GHz, 51 at 7 GHz and the values of inductance is 1.8, 1.5, 0.6 nH in the range of 5 GHz on the silicon, glass, and LTCC substrate, respectively.

Dielectric properties of low-loss dielectric materials are investigated with variation of silica filler which is known to be general filler in PCB composite. With comparison of dielectric losses of various filler materials in use of BCB resin, it could be known that crystalline cristobalite was superior to other crystalline or amorphous silica-base materials and reduced dielectric losses in the composite with resin. And dielectric properties of composite with the variation of filler quantity showed that amorphous silica and quartz increased dielectric loss as their quantities increased, while cristobalite increased little. As quantity of crystalline cristobalite phase increases in cristobalite/quartz intermediates, dissipation factor decreases.

Zn 2 SiO 4 ceramics synthesized by the conventional solid-state method exhibited a low Q × f value, possibly due to the formation of a ZnO second phase. However, with a small ZnO reduction from the Zn 2 SiO 4 ceramics, the ZnO second phase disappeared and grain growth occurred due to the formation of a Si-rich liquid phase. Specimens with a large grain size exhibited an improved Q × f value. In particular, the ceramics with nominal composition Zn 1.8 SiO 3.8 sintered at 1300°C exhibited improved microwave dielectric properties of e r = 6.6, Q × f = 147000 GHz, and τ f = -22 ppm/°C.

A novel, microchanneled tubular solid oxide fuel cell was fabricated using a multipass extrusion process, with an outside diameter of 2.7 mm that contained 61 cells. Cell materials used in this work were 8 mol% yttria-stabilized zirconia (8YSZ), La 0.8 Sr 0.2 MnO 3 (LSM), and NiO-8YSZ (50:50 vol%) as electrolyte, cathode, and anode, respectively. Three stages of heat-treatment processes were applied, at 700°C in N 2 condition, at 1000°C in air, and then sintered at 1300°C for 2 h, respectively. The X-ray diffraction analysis confirmed that no reaction phases appeared after sintering. The microstructures of anode and cathode were fairly porous while the electrolyte had a dense microstructure (relative density > 96%). The thickness of electrolyte, anode, and cathode were 20, 30, and 40 μm, respectively, and the diameter of the continuous channels was 150 μm.

We used the aqueous extract fromArtemisia campesttis ssp.caudata to investigate its effects on the colonization of sand dune grass roots by mycorrhizal fungi and seedling growth. The percent colonization decreased with higher extract concentrations, and growth of three grass species was inhibited. Colonization by mycorrhizal fungi was more sensitive to the extract than was seedling growth, and no significant differences in the latter were found between the mycorrhizal and non-mycorrhizal treatments.

The microstructure and microwave dielectric properties of dolomite type borates, CaZr(BO₃)₂ ceramics prepared by conventional mixed oxide method were explored. The sintering temperature of CaZr(BO₃)₂ ceramics could be reduced from 1150℃ to 925℃ with little amount of sintering additives. Microwave dielectric properties of 3 wt% Bi2O3-CuO added CaZr(BO₃)₂ ceramics sintered at 925℃ were K?10.4, Q×f ?80,000 ㎓ and TCF?+2 ppm/℃. Thus obtained LTCC tape was co-fired with Ag paste for compatibility test and revealed no sign of Ag reaction with the ceramics. Therefore, CaZr(BO₃)₂ ceramics is considered as a possible candidate material for low temperature co-fired multilayer devices.

Nano-sized LSM–YSZ composite was co-synthesized by a glycine–nitrate process (GNP). Transmission electron microscopy revealed that the as-prepared LSM–YSZ particles consist of nano-sized powders with a dominant YSZ phase. Backscatter electron image shows that LSM and YSZ phases were regularly dispersed within the composite. Alternating current impedance measurement revealed that the co-synthesized LSM–YSZ electrode shows lower polarization resistance and activation energy than the physically mixed LSM–YSZ electrode. This electrochemical improvement would be attributed to the increase in three-phase boundary and good dispersion of LSM and YSZ phases within the composite.