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This study was conducted to determine suppression of the anthracnose fungus (Colletotrichum coccodes), causing disease in persimmon trees (Diospyros kaki Thunb), by (1) extracts from various parts of 45 plant species from 27 families obtained using different extraction methods, and (2) selected plant extracts and emulsifiers. Fermentation extracts of Torilis japonica roots and Portulaca oleracea, all above ground parts, as well as ethanol extracts of Rheum palmatum roots and Cinnamomum cassia barks were found to effectively suppress anthracnose, leading to 83%, or more, suppression by 10% plant extracts in laboratory tests. Additionally, anthracnose was suppressed by 100% by 3% brown rice vinegar, 3% powder soap, 5% loess sulphur, and by 5% natural emulsifier-B in a laboratory test. In the field trial with organically grown persimmon trees, treatments with plant extracts used on their own, resulted a reduction of anthracnose by 63% and 51% by 5% fermentation extract of T. japonica and 5% ethanol extract of R. palmatum, respectively, compared with a control. However, in treatments with combinations of plant extracts and emulsifiers, anthracnose was reduced by 79%, 67%, 63% and 56% when treated with 5% fermentation extract of T. japonica + natural emulsifier-B (1%), 5% fermentation extract of T. japonica + loess sulphur (1%), 5% ethanol extract of R. palmatum + natural emulsifier-B (1%), and 5% ethanol extract of R. palmatum + loess sulphur (1%), respectively, compared with the control. Thus, mixtures of plant extracts and emulsifiers may be used to control anthracnose in organic production systems. [ABSTRACT FROM AUTHOR]

The choice of a production philosophy by a manufacturing company is important. Costs for holding inventory and costs for missing due-dates on customer orders are key components of overall profitability. In this paper, an optimization model of a new, yet simple, kind of horizontally integrated push/pull hybrid production system (HIHPS) is formulated that resolves the tradeoff between these two important cost components. At optimum, it will suggest either an allpush, all-pull, or a mixed operation configuration. A mixed system would be comprised of push stations followed by a cache of semi-finished product (SFP), followed by pull stations. An exact analytical solution of HIHPS is derived for the automated (low variability) case. A modification of the simulated annealing algorithm is presented to conduct the optimization search. Results of a case study are used to demonstrate the methodology and validate the model's predictions. [ABSTRACT FROM AUTHOR]

In recent years, deadlock issue has received considerable attention in the real-time control realm of automated manufacturing system (AMS). In this paper, we propose a simple and easily adaptable deadlock avoidance algorithm using a graph theoretic approach. Unlike Petri-net based methods which are complex and static from the viewpoint that once they are constructed and implemented, it is not easy to modify them as the system configuration is changed, and operate them coupled with other shop-floor control modules such as a dispatching controller, our algorithm can be used cooperatively with a dispatching controller and expanded with little modification. The core of the algorithm consists of two modules: resource allocation policy and a cycle detection method. In particular, the resource allocation policy is of importance in our algorithm because even though the cycle detection method is employed, deadlock may occur under wrong resource allocation policies. Throughout this paper, we propose a quasi two-step resource allocation policy with which our deadlock avoidance algorithm can detect and avoid deadlock just one step before deadlock. [ABSTRACT FROM AUTHOR]

In this study, coniferous (pitch pine,Pinus rigida) and broad-leaved (Oriental oak,Quercus variabilis) trees were gasified in a bubbling fluidized bed reactor, and the effects of reaction temperature and catalyst species on product yields and selectivities were systematically investigated. Upon increasing the gasification temperature from 800 to 900°C, the gas yield ofP. rigidamaintained similar values at 75.15–78.41%, while the gas yield ofQ. variabilisdecreased from 71.05 to 58.15% and the char and oil yields increased. The composition of gaseous products was affected according to catalyst species. When dolomite-based catalysts were used for fog biomass gasification, the hydrogen fraction increased substantially, while the carbon monoxide fraction decreased. [ABSTRACT FROM PUBLISHER]

Fast pyrolysis of spent coffee waste, a major non-cellulosic material, and oak wood chips, a cellulosic material, was carried out in a micro tubular reactor over a temperature range of 550 to 750°C with sweep gas flow rates of 20 and 500 mL/min. When the temperature was raised from 550 to 750°C, the gas yields were significantly enhanced, but the liquid yields were reduced. The highest liquid yield, 63.4 wt%, was obtained after pyrolysis of spent coffee waste at 550°C at a sweep gas rate of 500 mL/min. The highest gas yield, 65.74 wt%, was obtained after pyrolysis of the oak wood chips at 750°C at a sweep gas flow rate of 20 mL/min. The gas products primarily included considerable amounts of CO, CO2, and hydrocarbon-rich gases but no hydrogen. Furthermore, regardless of the biomass source, the hydrocarbon-rich gases were qualitatively similar and largely consisted of methane, ethane, ethylene, propane, and propylene. The gas chromatography-mass spectrometry analysis of the pyrolyzed bio-oils demonstrated that the major compounds were phenol derivatives, aldehydes, ketones, acids, and alcohols. [ABSTRACT FROM PUBLISHER]

Pure BiFeO3(BFO) and Gd-transition metal co-doped (Bi0.9Gd0.1)(Fe0.975B0.025)O3±δ(B= Ni, Mn, Cu, Ti, and V, denoted by BGdFNi, BGdFMn, BGdFCu, BGdFTi, and BGdFV) films were deposited by using a chemical solution deposition. Enhanced electrical properties were observed for the co-doped films. The BGdFMn film showed the largest 2Prvalue (105.3 μC/cm2at 1470 kV/cm) and the smallest leakage current density (1.49 × 10−5A/cm2at 100 kV/cm). The enhanced electrical properties for the co-doped films are related to the decrease of oxygen vacancies, the stabilization of perovskite structure, and the lattice distortion by the doping elements. [ABSTRACT FROM AUTHOR]

Recent development of a Simplified Murray-Darling Basin Model along with an auto-calibration capacity has advanced the ability to rapidly conceptualise and parameterise river system models. However in any process of conceptualisation, some simplifi cation may be warranted or desirable. In some cases the exact nature of stream connection in an anastomosing river network is diffi cult to determine. To more thoroughly assess the effect of simplification or error in stream network conceptualisation a range of river network conceptual models were assessed, ranging from as complex as the gauging network permits, to a simple single reach. Model performance is assessed by agreement with observed stream gauge data at various points for separate calibration and evaluation periods. The Lachlan catchment in central NSW was used as the test basin for this study. Results show that simplifi cation can result in similar goodness of fi t to less simple conceptual models. Care must be taken to avoid inclusion of gauges that increase model error in some downstream gauges. Errors in gauge data are propagated to downstream reaches, but the nature of the errors will determine how far the error persists as calibration moves further downstream. Flow based errors (eg. gauge rating error) and high frequency errors tend to become less detectable at more distant downstream gauges. [ABSTRACT FROM AUTHOR]

1. The present study was conducted to develop Citrus junos probioücs (CJP), using by-products of Citrus junos fermented with multispecies probiotic bacteria including Saccharomyces cerevisiae, Enterococcus faecium, Lactobacillus acidophilus and Bacillus subtilis. The effects of dietary CJP on the growth performance, immune status, caecal microbiology and meat oxidative stability of broiler were investigated. 2. A total of 240 one-day-old Ross broiler chicks were used in a 35-d experiment in which the chicks were randomly allotted to one of the 4 dietary treatments (0, 5, 10 and 20 g CJP/kg diet) in a completely randomised design. 3. Dietary supplementation of 5 g/kg CJP significantly increased body weight, average daily gain and average daily feed intake of broiler during the overall experimental period. 4. Serum immunoglobulin (Ig) M concentration was significantly increased by 10 and 20 g/kg CJP, whereas the IgG and IgA concentration remained unaffected. In addition, 20 g/kg CJP significantly inhibited proliferation of Escherichia coli without affecting the concentration of Lactobacillus or Bacillus spp. 5. A significant reduction in the thiobarbituric acid reactive substances values of breast and thigh meat was observed in response to increasing concentration of dietary CJP. 6. Thus, the results suggest that CJP up to a concentration of 20 g/kg can be used in the diet of broilers to improve immunity and to reduce caecal E. coli and TBARS values of breast and thigh meat without any adverse effects on growth performance. [ABSTRACT FROM AUTHOR]

Lead-free polycrystalline (K0.48Na0.52)1+x(Nb0.55Ta0.45)O3(x = 0, 0.01, 0.02 and 0.03) thin films have been grown on Pt(111)/Ti/SiO2/Si substrates using KrF excimer laser ablation to investigate the effects of A-site ion excess. The film at x = 0.01 exhibited good ferroelectric hysteresis loop with a remnant polarization 2Prof 30 μC/cm2and coercive field 2Ecof 61 kV/cm. The piezoelectric coefficientd33,fof the KNNT film with x = 0.01 was found to amount to 79 pm/V. These improved ferroelectric and piezoelectric properties were attributed to the excess of A-site Na and K ions. [ABSTRACT FROM PUBLISHER]

Pure Bi6Fe2Ti3O18and vanadium (V) doped Bi6Fe2Ti3O18(Bi5.99Fe2Ti2.75V0.03O18) thin films were prepared on Pt(111)/Ti/SiO2/Si(100) substrates by a chemical solution deposition method. The Bi5.99Fe2Ti2.75V0.03O18thin film exhibited improved electrical and multiferroic properties, such as leakage current densities, dielectric properties, ferroelectric and ferromagnetic properties. We consider that the improved properties might be related to the reduced concentration of oxygen vacancies and the decreased mobility of oxygen vacancies by V doping. [ABSTRACT FROM PUBLISHER]

Copyrolysis of two waste wood samples with block polypropylene were investigated for the reaction characteristics and properties of the pyrolytic oil. The thermal decomposition of the mixture led to an increase in the temperature range for the decomposition of polypropylene, which implied an interaction in the mixture. New tar compounds were also identified from the copyrolysis using pyrolysis gas chromatography/mass spectrometry. The oil produced from the mixtures in a batch type reactor had an increase in the mass yield, with higher C and H, and lower moisture contents. [ABSTRACT FROM AUTHOR]

We have evaluated the ferroelectric and electrical properties of pure BiFeO3(BFO) and (Bi0.9Ho0.1)(Fe0.975Ti0.025)O3+δ(BHFTO) thin films on Pt(111)/Ti/SiO2/Si(100) substrates by using a chemical solution deposition method. The improved electrical properties were observed in the BHFTO thin film. The leakage current density of the co-doped BHFTO thin film showed three order lower than that of the pure BFO, 1.22 × 10−6A/cm2at 100 kV/cm. The remnant polarization (2Pr) and the coercive electric field (2Ec) of the BHFTO thin film were 61 μC/cm2and 1190 kV/cm at an applied electric field of 800 kV/cm and at a frequency of 1 kHz and these values decreased with increasing measurement frequency, 35 μC/cm2and 920 kV/cm at 10 kHz, respectively. Also, the 2Prand the 2Ecvalues were fairly saturated above 30 kHz. [ABSTRACT FROM PUBLISHER]

Multiferroic Bi(Fe0.9Mnx0.1)O3(x= 2+, 3+, and 4+) thin films were prepared on Pt(111)/Ti/SiO2/Si(100) substrates by using a pulsed laser deposition method. The effects of different oxidation states of Mn used as a starting material on crystal structure, leakage current, dielectric, and ferroelectric properties were investigated. No significant change in the crystal structure was observed while electrical properties were affected by the oxidation states of Mn. A frequency-dependent dielectric relaxation region was observed in the films with Mn3+and Mn2+, indicating the presence of space charges such as oxygen vacancies. [ABSTRACT FROM AUTHOR]

Pure Bi5FeTi3O15and its doped compounds, such as Bi4.15La0.75FeTi3O15and Bi4.15Nd0.85FeTi3O15thin films, were prepared on Pt(111)/Ti/SiO2/Si(100) substrates by using a chemical solution deposition method. The crystalline structures and the surface morphologies of the thin films were identified by using an X-ray diffractometry, a Raman spectroscopy, and a scanning electron microscopy. In addition, the comprehensive electrical properties of the thin films, such as ferroelectric hysteresis loops and leakage current densities, were characterized by using a precision materials analyzer and an electrometer at room temperature, respectively. [ABSTRACT FROM AUTHOR]

Effects of heat-treat procedure and sintering temperatures were investigated in 0.67Bi1.05FeO3-0.33BaTiO3ceramics. The structure, dielectric, ferroelectric, and piezoelectric properties of ceramics made by normal cooling or quenched cooling process were investigated. All ceramics show single pseudo-cubic perovskite crystal structure. Although the structure was not changed but other properties were much changed by heat-treatment. The normally cooled ceramic showed ‘pinched’ ferroelectric hysteresis loops with remanent polarization value of about 10 μC/cm2. On the contrary, the quenched ceramic showed ‘normal’ ferroelectric hysteresis loops with remanent polarization value of about 17 μC/cm2. The piezoelectric constantd33value of 13 pC/N in normally cooled ceramic was improved to 39 pC/N in quenched ceramic. These improved results were attributed to the reduced populations of defects made during the heat-treatments. [ABSTRACT FROM AUTHOR]

A phenomenological approach to explain the change of phase transition temperatures (TC) of Pb(Zr,Ti)O3-BiFeO3(PZT-BF) mixed system was proposed. By introducing coupling terms independent of composition together with the averaged free energy terms, the change of TCwas well explained in PbTiO3-BiFeO3(PT-BF) mixed system. From the parameters obtained from PT-BF system ofa1anda11in Landau-Devonshire theory, we could explain the change of TCin PZT-BF system in tetragonal phase. [ABSTRACT FROM PUBLISHER]

We prepared pure BiFeO3(BFO) and co-doped (Bi0.9Nd0.1)(Fe0.975V0.025)O3+δ(BNFVO) thin films on Pt(111)/Ti/SiO2/Si(100) substrates by using a chemical solution deposition method. Improved electrical properties were observed in the co-doped BNFVO thin film. The leakage current density of the co-doped BNFVO thin film was four orders of magnitude lower than that of the pure BFO, 2.6 × 10−7A/cm2at 100 kV/cm. The remnant polarization (2Pr) and the coercive electric field (2Ec) of the co-doped BNFVO thin film were 56 μC/cm2and 1393 kV/cm at an applied electric field of 1110 kV/cm and at a frequency of 1 kHz, and the values decreased with increasing measurement frequency to 18 μC/cm2and 1282 kV/cm at 10 kHz, respectively. We also confirmed that the remnant polarization (2Pr) and the coercive electric field (2Ec) were fairly saturated above a measurement frequency of 20 kHz for the BNFVO thin film. [ABSTRACT FROM AUTHOR]

Bismuth ferrite BiFeO3(BFO) and holmium (Ho)-chromium (Cr) co-doped bismuth ferrite (Bi0.9Ho0.1)(Fe0.975Cr0.025)O3, (BHFCr) thin films were deposited on Pt(111)/Ti/SiO2/Si substrates by using a chemical solution deposition method. Effects of Ho and Cr co-doping on the micro-structures, ferroelectric properties and leakage current densities of the thin films were investigated. The single-phase rhombohedral perovskite structures of the thin films were confirmed by an X-ray diffraction analysis. From the electrical property studies, the BHFCr thin film showed enhanced electrical properties compared to the BFO thin film. The improved electrical properties of the BHFCr thin film are correlated with greatly improved microstructure, stabilization of the perovskite structure and defects compensation. [ABSTRACT FROM AUTHOR]

It has been well known that BiFeO3 (BFO) exhibits two interesting physical properties simultaneously, which invoked multi-ferroic device applications to change electrical properties by controlling magnetic properties of BFO or vice versa. However, BFO has a high leakage current density, which may be attributed to bismuth and/or oxygen vacancies in the structure. In order to reduce the leakage current, a thin layer of dielectric SrTiO3 (STO) has been deposited on the top of BFO films by pulsed laser deposition. Improvement in leakage current and remnant polarization was observed in the STO capped BFO thin films. [ABSTRACT FROM AUTHOR]

(Na0.53+x K0.47)(Nb0.55Ta0.45)O3 (NKNT) ceramics prepared by a solid state process were investigated at 0 ≤ x ≤ 0.02 to determine the effects of Na content in NKNT ceramics. With Na nonstoichiometry, piezoelectric properties were varied but grains were all cube-like perovskites with no impurity phases. Piezoelectric coefficient (d 33) was sensitive to Na content while polymorphic phase transition (PPT) temperature was not. PPT temperature between orthorhombic and tetragonal phases (T O-T) was around room temperature within the compositional range tested. The highest d 33 obtained was 330 pC/N at Na0.545 (x = 0.015) increased from 310 pC/N at Na0.53 (x = 0), which was due to the morphotropic phase boundary (MPB) effect around (Na0.53K0.47) of NKNT ceramics. [ABSTRACT FROM AUTHOR]

The effects of Li substitution on K in (Na0.53K0.47-x Li x )NbO3 (NKLN) ceramics prepared by a solid state process were studied at 0 ≤ x ≤ 0.09. Phase purity was maintained up to x = 0.04, then a secondary phase started emerging. With increasing Li substitution, partial melting appeared to occur and grain size increased. Polymorphic phase transition (PPT) temperatures, T O-T between orthorhombic and tetragonal phases and T C between tetragonal and cubic phases, were significantly affected by Li substitution. With increasing x, T O-T decreased while T C increased extending the tetragonal phase region. The highest d 33 of 220 pC/N was obtained at x = 0.07 mol at which high apparent density of the sintered pellets was obtained despite the formation of an impurity phase. [ABSTRACT FROM AUTHOR]

(Eu, Mn) co-doped bismuth ferrite [(Bi0.9Eu0.1)(Fe0.9Mn0.1)O3 (BEFMO)] thin films were deposited on Pt(111)/Ti/SiO2/Si substrates by using a chemical solution deposition method. The coated films were annealed in N2, air and O2 atmospheres at 550°C for 30 min. Effects of annealing atmosphere on the crystal structure, ferroelectric properties and leakage current density of the BEFMO thin films were investigated. The single-phase rhombohedral perovskite crystal structure of all the samples was confirmed by x-ray diffraction analysis. From the electrical studies, the BEFMO thin film annealed in air atmosphere showed better electrical properties than O2 and N2 atmosphere annealed samples. The largest remnant polarization 96.4 μC/cm2 at an electric field 1060 kV/cm was obtained from the BEFMO thin film annealed in air. [ABSTRACT FROM AUTHOR]

Thin films of BiFeO3 (BFO), Bi0.9Eu0.1Fe0.975Cu0.025O3-δ (BEuFC) and Bi0.9Dy0.1 Fe0.975Cu0.025O3-δ (BDyFC) were prepared on Pt(111)/Ti/SiO2/Si(100) substrates via a chemical solution deposition method. X-ray diffraction and Raman studies show distorted rhombohedral perovskite crystal structure for all the samples. Micro structural features and morphological changes of the BFO, BEuFC and BDyFC were examined by using a FE-SEM analysis. The leakage current density was found to be greatly reduced for the BEuFC and the BDyFC thin films. The largest remnant polarization (2Pr) 68 μC/cm2 (at 1336 kV/cm) and the lowest coercive field (2Ec) 845 kV/cm (at 931 kV/cm) were observed from the BEuFC and the BDyFC thin films, respectively. [ABSTRACT FROM AUTHOR]

The structural and electrical properties of BiFeO3 (BFO) and rare earth metal ions (Re) co-substituted (Bi0.9Re0.1)(Fe0.9Mn0.1)O3-δ (Re = Nd, Sm, Ce and Tb) thin films prepared on Pt(111)/Ti/SiO2/Si(100) substrates via a chemical solution deposition method were investigated. The significant decrease of leakage current density and improved ferroelectric properties were observed from the co-substituted thin films. The largest remnant polarization (2Pr) (61.7 μC/cm2) and the lowest coercive field (2Ec) 657 kV/cm at 931 kV/cm were measured from the (Bi0.9Ce0.1)(Fe0.9Mn0.1)O3-δ thin film. The leakage current density value of (Bi0.9Sm0.1)(Fe0.9Mn0.1)O3-δ thin film (3.29 × 10−5A/cm2) was found to be two order lower than that of the pure BFO. [ABSTRACT FROM AUTHOR]

Ferroelectric K0.5Bi4.5Ti4O15 (KBTi) and Cr-doped K0.5Bi4.5Ti4O15 ((K0.5Bi4.5Ti3.97 Cr0.03O15-δ), (KBTC)) thin films were prepared on Pt(111)/Ti/SiO2/Si substrates by using a chemical solution deposition method. The thin films were annealed at 750°C for 3 min by a rapid thermal annealing process under oxygen atmosphere. Compared to pure KBTi thin film, there was no structural change while improved ferroelectric and leakage current properties were observed. The values of remnant polarization (2Pr ) and coercive field (2Ec ) were 50.9 μC/cm2 and 244 kV/cm at an applied electric field of 300 kV/cm, respectively. The 2Pr we observed is compatible with that of doped bismuth layer-structured ferroelectric thin films. Leakage current density was 6.00 × 10−7 A/cm2 at 200 kV/cm. The enhanced properties of KBTC could be explained by a defect dipole (Cr′Ti-V) and increased average grain size. [ABSTRACT FROM AUTHOR]

The microstructure, dielectric and leakage current characteristics of Bi(Fe1-xTix)O3 (x = 0-0.2) polycrystalline ceramics have been investigated. Phase transformation from rhombohedral to orthorhombic symmetry occurs at around x∼0.2. Average grain size decreases rapidly and then saturates with the size of few μm above x = 0.025. The steplike decrease in ε for the composition of x = 0 and 0.01 are related dielectric relaxation. Leakage currents were much decreased by about 6 orders of magnitude above x = 0.025. Similarly to the results of SEM images and dielectric constants, leakage currents were changed with Ti substitution. [ABSTRACT FROM AUTHOR]

Randomly oriented and c-axis-oriented Bi3.15Pr0.85Ti3O12 (BPT) thin films were prepared by a chemical solution deposition method. Ferroelectric and leakage current properties were strongly related to the crystallographic orientation of BPT thin film. The values of remnant polarization (2Pr) and leakage current density were 74 μC/cm2 at 250 kV/cm and 3.4 × 10-8 A/cm2 at 125 kV/cm for the randomly oriented thin film, respectively, and 16 μC/cm2 and 6.9 × 10-6 A/cm2 for the c-axis-oriented thin film, respectively. The result indicates that the polarization vector of BPT thin films is not oriented along the c-axis. [ABSTRACT FROM AUTHOR]

V-doped Na0.5Bi4.5Ti4O15 (Na0.5Bi4.5-x/3Ti4-xVxO15, NaBTiV-x, x = 0.00, 0.01, 0.03, and 0.05) thin films were prepared on a Pt(111)/Ti/SiO2/Si(100) substrate by a chemical solution deposition method. NaBTiV-0.01 thin film exhibited the most outstanding electrical properties among them. The value of remnant polarization (2Pr) was 61 μC/cm2 and the leakage current density of the thin film capacitor was approximately one order of magnitude lower than that of pure Na0.5Bi4.5Ti4O15 thin film capacitor. We consider that the enhanced properties may be related to reduced oxygen vacancies by doping vanadium. [ABSTRACT FROM AUTHOR]

Dielectric and piezoelectric properties of lead-free (1-x)(Bi0.5K0.5)TiO3-xBiFeO3 ceramics prepared by a conventional solid-state reaction method were studied in the range of x = 0∼40 mol%. A tetragonal perovskite structure was maintained at x = 0∼10 mol% forming a solid solution between (Bi0.5K0.5)TiO3 and BiFeO3 with no secondary phase. Piezoelectric coefficient (d33) increased from 31 pC/N at x = 0 mol% to 64 pC/N at x = 6 mol% and then decreased with further addition of x. Depolarization temperature (Td) gradually decreased with increasing x from 302°C at x = 0 mol% to 163°C at x = 20 mol% and slightly increased up 180°C at x = 40 mol%. [ABSTRACT FROM AUTHOR]

Dielectric and piezoelectric properties of (Bi0.5K0.5+xLiy)TiO3 ceramics were studied in the range of x = -8-1 and y = 0-5 mol% of the stoichiometric K0.5. Secondary phases were not observed within -1 ≤ x ≤ 1 but started emerging at x ≤ -2 mol%. A tetragonal perovskite structure was maintained at all compositions despite the formation of secondary phases with K deficiency. Piezoelectric coefficient (d33) was improved due to K-vacancies facilitating domain walls movement and was further enhanced due to the microstructure improved with the tetragonality optimized by Li addition. Depolarization temperature (Td), on the other hand, depressed with K deficiency and Li addition. [ABSTRACT FROM AUTHOR]

Wide band gap ZnS-ZnO thin films were grown on c-Al2O3 by a pulsed laser deposition method using a pure ZnS target with a fixed substrate temperature of 600°C and a range of oxygen partial background pressures of 5 × 10-5∼50 Torr. With low oxygen deposition pressures, films were found to be mainly ZnS. However, with high oxygen pressures, the deposited thin films were found to be mainly ZnO. The formation of the ZnO films with high oxygen pressure could be attributed to the fast chemical reaction of O and S in the deposition chamber during deposition. It was found that there is a good linear correlation between measured energy band gaps and S/Zn atomic ratio of the films as expected. [ABSTRACT FROM AUTHOR]

Ferroelectric and leakage current behaviors of Zn-Mn co-doped polycrystalline BiFeO3 (BFO) thin films fabricated by a pulsed laser deposition were investigated in comparison with un-doped BFO thin films. Ferroelectric hysteresis loop was observed in Zn-Mn co-doped BFO film capacitor: 2Pr = 109 μC/cm2 and 2EC = 674 kV/cm with maximum electric field of 600 kV/cm. And leakage current was reduced with Zn-Mn co-doping at low electric field region and 10 mol% Bi-excess BFO film has best leakage current behavior in a wide electric field range. [ABSTRACT FROM AUTHOR]

Effects of Bi(Zn0.5Ti0.5)O3 (BZT) substitution in Pb(Zr1-xTix)O3 (PZT) piezoelectric ceramics were investigated. Morphotropic phase boundary was observed at x = 0.48 and high piezoelectric properties were observed similarly to the un-substituted PZT ceramics. Piezoelectric properties were improved with 5 mol% BZT substitution. The ferroelectric transition temperatures were decreased by about 45°C with 5 mol% BZT substitution contrary to the increase of the transition temperature with BZT substitution in PbTiO3. [ABSTRACT FROM AUTHOR]

K nonstoichiometry effects in (Bi0.5K0.5+x)TiO3 (BKT) ceramics were studied with K contents varying in the range of -8≤ x ≤+1 mol% from the stoichiometric K0.5. Within the range tested, a single BKT phase region was found to be at -1≤ x ≤+1 mol% and secondary phases started emerging with further K deficiency. Despite the formation of secondary phases, BKT perovskite with tetragonal symmetry was retained at all compositions. For nonstoichiometric BKT perovskite, a composition dependent structure property relation was observed; a decrease in tetragonality (c/a) caused piezoelectric coefficient (d33) enhanced while depolarization temperature (Td) reduced and vice versa. [ABSTRACT FROM AUTHOR]

For electromagnetic suspension (EMS) type urban Maglev vehicles using a U-shaped electromagnet, the levitation and guidance forces are generated by only one electromagnet. Although the levitation force is actively controlled by changing the voltage of the electromagnet, the guidance force is passively determined by the levitation force. In addition, the curve negotiation performance of EMS-type urban Maglev vehicles using a U-shaped electromagnet must be considered, because an urban guideway may have some curves with shorter radii. It is, therefore, necessary to predict the curving performance with the greatest accuracy possible, in order to improve electromagnetic suspension and establish guideway design specifications. The objective is to establish a new dynamic modelling technique, so as to achieve more realistic curving simulation and thus to more accurately evaluate the curving performance of an EMS-type Maglev vehicle. The use of a full vehicle multibody dynamic model is proposed, and is applied to the evaluation of curving performance. Design changes are also investigated to obtain the bogie design directions for minimising variation in the lateral air gap, which is a criterion for curving performance. [ABSTRACT FROM AUTHOR]

A-site non-stoichiometric lead-free 0.93(K0.5Na0.5)(1 + x)NbO3-0.07LiNbO3 (KNNL) piezoelectric ceramics were prepared by a solid state reaction. The contents of both K and Na were simultaneously controlled to -4 mol% deficient. The K3Li2Nb5O15 second phase was observed in most of the composition except for 0 mol%. The polymorphic phase transition (PPT) between the tetragonal and orthorhombic phases was found from X-ray diffraction and temperature-dependent dielectric constant at around -2 mol%. With increasing (K+Na) ion deficiency, the PPT temperature of KNNL ceramics increased but Curie temperature (TC) decreased. The piezoelectric constant was 155 pC/N for nominally stoichiometric KNNL and decreased as decreasing (K+Na) content. [ABSTRACT FROM AUTHOR]

The effects of Bi(Zn0.5Ti0.5)O3 (BZT) substitution in BaTiO3 (BT) or (Bi0.5Na0.5)TiO3 (BNT) piezoelectric ceramics were studied. (1-x)BaTiO3-xBi(Zn0.5Ti0.5)O3 (x = 0.02, 0.04, 0.06, 0.08, 0.10, 0.20, 0.30, and 0.40) and (1-y)(Bi0.5Na0.5)TiO3-yBi(Zn0.5Ti0.5)O3 (y = 0, 0.01, 0.025, 0.05, 0.10, and 0.20) ceramics were prepared by a solid state reaction method. The structures and surface morphologies have been examined using an X-ray diffraction and scanning electron microscopy, respectively. The grain size and density increased with increasing the amount of BZT in both systems. Curie temperatures (TC) were decreased as BZT substituted. Piezoelectric properties also decreased with the substitution of BZT. [ABSTRACT FROM AUTHOR]

Ferroelectric Na0.5Bi4.5Ti4O15 (NaBTi) thin films, selectively controlled in c-axis and random orientation, were fabricated on a Pt(111)/Ti/SiO2/Si(100) substrate by using a chemical solution deposition method. The preferred orientation of the thin films annealed at 750°C under oxygen atmosphere was confirmed by X-ray diffraction and scanning electron microscope studies. We found that ferroelectric, dielectric, and leakage current properties were strongly related to the crystallographic orientation of NaBTi thin films; the randomly oriented NaBTi thin film exhibited better properties than the c-axis oriented thin film. The values of remnant polarization (2Pr), dielectric constant, and leakage current density were 21 μC/cm2 at 300 kV/cm, 630 at 100 kHz, and 7.4 × 10-6 A/cm2 at 100 kV/cm for the randomly oriented thin film, respectively, and 6 μC/cm2, 420, and 1.1 × 10-1 A/cm2 for the c-axis oriented thin film, respectively. Also, no polarization fatigue was observed in both NaBTi thin films up to 107 switching cycles. [ABSTRACT FROM AUTHOR]

The levitation control system in an electromagnetically levitated vehicle controls the voltage in its winding to maintain the air gap, which is the clearance between the electromagnet and the guideway, within an allowable range of variation, while strongly interacting with the flexible guideway. Thus, the vibrational characteristics of the guideway play an important role in the dynamics of Maglev (magnetically levitated) vehicles that utilise an active electromagnetic suspension system. In this study, the effects of the guideway's vibrational characteristics, such as natural frequency and damping, on the dynamics of the Maglev vehicle UTM-02 are numerically and experimentally analysed. From these analyses, the coupled equations of motion of the simplified vehicle-guideway model with three degrees of freedom are derived. Eigenvalues are calculated and frequency response analysis is also performed, in order to obtain a clear understanding of the dynamic characteristics resulting from the guideway's vibrational characteristics. To verify the numerical results, air gap tests of the urban Maglev vehicle UTM-02 are also carried out. These results lead us to recommend that the natural frequency of the guideway be decreased by increasing mass density rather than by decreasing rigidity, and that its damping ratio be increased in the Maglev vehicle UTM-02 employing a five-state feedback control law as a levitation control law. [ABSTRACT FROM AUTHOR]

Ferroelectric CaBi4Ti4O15 (CBTi) thin films with random orientation and high c-axis orientation were prepared on a Pt(111)/Ti/SiO2/Si(100) substrate by a chemical solution deposition method. We observed a strong dependence of ferroelectric and dielectric properties on the film orientation. The CBTi thin film with random orientation exhibited remnant polarization (2Pr) of 54 μ C/cm2 at an applied electric field of 250 kV/cm and dielectric constant (ε) of 412 at a frequency of 1 kHz. The values of 2Pr and ε were larger than those observed in the CBTi thin film with high c-axis orientation. In addition, the randomly oriented thin film showed lower leakage current density than the highly c-axis-oriented thin film. [ABSTRACT FROM AUTHOR]

SrBi5FeTi4O18 (SBFT) thin films were prepared on a Pt(111)/Ti/SiO2/Si(100) substrate using a chemical solution deposition method and annealed at 650°C under oxygen atmosphere. It was found that the polycrystalline SBFT thin film exhibits good ferroelectric properties. The values of remnant polarization (2Pr) and coercive electric field (2Ec) were 33 μ C/cm2 and 150 kV/cm at an applied electric field of 250 kV/cm, respectively. Leakage current density of the thin film was 106 A/cm2 at 100 kV/cm. The values of dielectric constant and dielectric loss were 470 and 0.05 at 1 kHz, respectively. No significant polarization fatigue was observed up to 1.44 × 1010 switching cycles. Also weak ferromagnetic properties were observed. [ABSTRACT FROM AUTHOR]

Cr-substituted BiFeO3 (BFCr-3 mol%) thin films were deposited on Pt(200)/TiO2/SiO2/Si substrates by a chemical solution deposition. The coated films were annealed in the temperature range of 500°C∼ 600°C for 30 min under nitrogen atmosphere. The electrical properties of BFCr thin films were found to be sensitive to the annealing temperature. It was found that BFCr thin films exhibited good ferroelectric properties, such as an improved leakage-current density and P-E hysteresis characteristics. The BFCr thin film annealed at 525°C exhibits a low leakage current density of 9.2 × 10- 7 A/cm2 at an applied electric field of 100 kV/cm. The films exhibited a well-saturated hysteresis loop with a remanent polarization (Pr) of 47 μC/cm2 at room temperature. The reason for the improved leakage current and ferroelectric properties in BFCr thin films can be attributed to the effects of increased grain size and oxygen vacancies reduced by Cr doping. [ABSTRACT FROM AUTHOR]

To retard the migration of iodine released from a spent fuel after the break of a container, the reducing effects on the concentration of the iodide by container corrosion products and some buffer additives were examined in a solution with bentonite. Iron and copper, and their corrosion products scarcely reduced the iodide concentration. And kaolinite, chalcopyrite, pyrite, copper ore and galena, known as having a sorption property for iodine, did not noticeably sorb the iodide. However, palm active carbon, silver metal and Ag2O lowered the iodide concentration. Especially, Ag2O put into a disposal container would effectively hinder the migration of iodine to the outside of a disposal vault without a great loss if the pore size of the compacted buffer layer is maintained below 1 μ m. [ABSTRACT FROM AUTHOR]

5 mol % La3 +, Nd3 + or Y3 +-cosubstituted BiFe0.97Cr0.03O3 thin films (denoted by BLaFCr, BNdFCr, and BYFCr, respectively) have been successfully deposited on Pt (200)/TiO2/SiO2/Si substrates by a chemical solution deposition method. Well-saturated ferroelectric hysteresis loops and low leakage current densities have been observed in BLaFCr, BNdFCr, and BYFCr thin films with single-phase structure. The values of remanent polarization (Pr) and coercive field (Ec) were 64 μ C/cm2 and 275 kV/cm, 61 μC/cm2 and 290 kV/cm, and 31 μ C/cm2 and 315 kV/cm for BLaFCr, BNdFCr and BYFCr thin films at the maximum electric field of 712 kV/cm, respectively. In the present study, the differences in values of Pr seem to be related to the doped ionic radii. [ABSTRACT FROM AUTHOR]

Cu-doped Ba0.7Sr0.3TiO3 (BST) thin films were prepared on Pt(111)/Ti/SiO2/Si(100) substrates by a sol-gel spin coating process. The coated thin films were annealed at 750°C for 3 min in oxygen, air and nitrogen atmospheres by a rapid thermal annealing process. All of the Cu-doped BST thin films were consisted of a single phase perovskite structure and exhibited smooth crack-free surfaces. We investigated the effects of the annealing atmosphere on the microstructure and the electrical properties of the Cu-doped BST films. The Cu-doped BST film by annealing in oxygen exhibits a dielectric constant of 923 with electric field dependent tunability of 48.6% at electric field 250 kV/cm and a leakage current density of 1.82 × 10- 5A/cm2 at electric field of 150 kV/cm. [ABSTRACT FROM AUTHOR]

A spent LWR fuel specimen between Ca-bentonite blocks was leached in a simulated bentonite-saturated granitic water (SBGW) for 165 days and its results were compared with those of a specimen leached without a bentonite block. The amounts of Cs, Sb, Sr, Eu, Am, U and Pu released from a 4.3 mm thickness of a fuel pellet with a 50,400 MWD/MTU burn-up in the SBGW without a bentonite block were 2.2, 0.25, 0.15, 0.02, 0.01, 0.01 and ∼⃒5 × 10 -4 % of their inventories, respectively. However, the amounts of nuclides released from the specimen between the 1.4 Mg/m 3 bentonite blocks were decreased by three times at least. Moreover, the concentrations of the nuclides in the leachate were very low because most of them were retained in the bentonite blocks. [ABSTRACT FROM AUTHOR]

Recently perovskite niobates were paid much attention as lead-free piezoelectric materials to replace lead-based Pb(Zr,Ti)O3 or relaxor systems which cause much environmental problems. Piezoelectric and ferroelectric properties of electromechanical coupling coefficient and quality factor in (K0.5Na0.5)NbO3 ceramic were studied. Dielectric properties of niobates including Ag ion; AgNbO3 and (Ag0.5Na0.5)NbO3 were studied. Phase transitions and dielectric relaxations were studied from the frequency and temperature dependent dielectric constant measurements. The piezoelectric properties were hardly observed in silver niobate systems. [ABSTRACT FROM AUTHOR]

A new type of bismuth-based relaxor, such as Bi 2 (Y 1/2 Nb 1/2 ) 2 O 7 and Bi 2 (Mg 1/3 Nb 2/3 ) 2 O 7 thin films were fabricated on Pt/Ti/SiO 2 /Si substrate by a sol-gel spin coating process. The films exhibit characteristic diffused phase transition. The temperature dependent reciprocal dielectric constant characteristics of the films deviates from the Curie-Weiss law in the temperature range over the dielectric constant maximum temperature ( T m ). The diffuseness of the phase transition of the thin films was estimated by calculating the difference between T m and T cw (starting temperature following the Curie-Weiss law). For the thin films annealed at 750°C, the temperature T m , the Curie-Weiss temperature Θ, the Curie-Weiss constant c and the temperature T cw were measured at frequency of 10 3 Hz, respectively. [ABSTRACT FROM AUTHOR]

The formation of phase-pure BiFeO 3 (BFO) thin films using a chemical solution deposition on platinium electrode has been investigated systematically by changing the annealing condition of the films. From the X-ray diffraction results, it was found that the formation of the phase-pure BFO was favorable under lower oxygen partial pressure, slower heating rate and Pt(200)/Ti/SiO 2 /Si(100) substrate. The remanent polarization ( P r ) and coercive field ( E c ) values of the phase-pure BFO thin film annealed at 600°C in nitrogen atmosphere by conventional furnace annealing method are approximately 0.9 μC/cm 2 and 20 kV/cm, respectively. [ABSTRACT FROM AUTHOR]

Well c-axis oriented 320 nm and 160 nm thick ZnO thin films were deposited with pulsed laser deposition on Pt/Ti/SiO 2 /Si(100) substrates. Diode characteristics of Au/ZnO/Pt in electrical conductivity were observed. The conductivity in forward bias was sensitive to the hydrogen annealing but almost insensitive in reverse bias. The conductivity of 320 nm thick film in forward bias increased from 6.1 × 10 -5 Ω -1 cm -1 in as-deposited film to 3.3 × 10 -3 Ω -1 cm -1 in hydrogen annealed one at 200 &circle; C. The observed dielectric constant 70 was much higher than that of ceramic ZnO. Dielectric anomaly at about 1 kHz was observed and attributed to the space charge. [ABSTRACT FROM AUTHOR]