Search

Using computer-controlled pulsed laser deposition, high quality SrMoO3 thin films have been epitaxially grown on SrTiO3 (001) substrates. A growth interruption technique was employed for better epitaxy, and layer-by-layer growth was obtained by the intensity oscillations of reflection high-energy electron diffraction. The films were of epitaxial crystallinity as characterized by high-resolution transmission electron microscopy. The typical root mean square surface roughness was 2.2 A. The SrMoO3 thin films showed metal-like conducting behavior with resistivity on the order of 60–120 μΩ cm between 4 K and room temperature. An x-ray photoelectron spectroscopy study shows that the valence band spectrum of the film has the typical character of a metal, and Mo 4dt2g electrons are responsible for the conduction of the films.

Low-dimensional GaN materials, including nanorings, nanoribbons and smooth nanowires have been synthesized by reacting gallium and ammonia using Ag particles as a catalyst on the substrate of MgO single crystals. They were characterized by field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). EDX, XRD indicated that the low-dimensional nanomaterials were wurtzite GaN. New features are found in Raman scatterings for these low-dimensional GaN materials, which are different from the previous observations of GaN materials.

In this paper, the subsolidus phase relations of the ternary system MgO-Ga2O3-B2O3 were investigated. There are five binary compounds and one ternary compound. The ternary phase diagram consists of eight ternary phase regions. The ternary compound, GaMgBO4, is isostructural to Y2BeO4. It crystallizes in the orthorhombic system with the space group Pnam and lattice parameters a=9.1847(1) Angstrom, b=9.2942(1) Angstrom, c=3.0779(1) Angstrom, Z=4 and rho (cal.) = 4.267 g/cm(3). The Mg2+ and Ga3+ ions are distributed between the two cation sites: 77.8% Ga3+ and 22.2% Mg2+ occupy the cation site I, others (22.2% Ga3+ and 77.8% Mg2+) occupy the cation site II. In this structure the Mg2+ and Ga3+ ions are surrounded octahedrally by oxygen atoms, the berate ion is a single triangle (BO3). The most important feature of this structure is the way these octahedra are linked together by sharing edges to form ribbons, which are one octahedron thick and four octahedra wide in the ab plane and extend infinitely along the direction of the c axis. The XRD results show no phase transition occurs between -173 degreesC and 227 degreesC. The lattice parameters and the volume expansion coefficient were calculated. (C) 2001 Elsevier Science B.V. Al rights reserved.

The subsolidus phase relations of the system La2O3-CaO-B2O3 are investigated by means of X-ray diffraction (XRD) analyses. There are seven binary compounds and five ternary compounds in this system. The phase diagram comprises eighteen three-phase regions. A new ternary compound Ca4LaO(BO3)(3) (CLOB) is identified. It has a monoclinic structure with cell parameters a=8.1732(1) Angstrom, b=16.0860(3) Angstrom, c=3.6268(1) Angstrom, beta =101.40(1)degrees and space group Cm. At low temperature, the XRD patterns of the CLOB compound indicate that a phase transition in the low temperature range is absent. The expansion coefficients in the three major directions are different, the value of alpha (c) being the largest. (C) 2001 Elsevier Science B.V. All rights reserved.

In this letter, we analyze the morphological stability of a nanowire during the vapor–solid (VS) side growth process at the same time as it grows along its axial direction by the vapor–liquid–solid (VLS) mechanism. The longitudinal perturbations due to the fluctuations of the growth conditions are introduced to describe the morphological variance of a nanowire along its fibre direction. It is shown that the side growth can induce the morphological instability for a nanowire with side perturbations if the perturbation's wavelengths are larger than a nanowire's perimeter.

In this brief paper, wt: address the problem of the radial growth dynamics of a nanowire due to the vapor-solid (VS) process while at the same time it grows along its axial direction due to vapor-liquid-solid (VLS) process. We show that there exists a critical radius at a certain saturation and that the nanowire will thicken if its initial radius is larger than the critical radius and vice versa. Only when its initial radius is equal to the critical radius will the radius of the nanowire be uniform along its axial direction. In all other cases, the nanowire is tapered with a certain slope. The slope is relevant to the initial radius. The closer it is to the critical radius, the smaller is the slope and vice versa. Although the slope may be generally very small, it still does exist. This suggests that it is difficult to grow long nanowires with a uniform radius. (C) 2001 Published by Elsevier Science B.V.

Blood fibrinogen concentrations and glutamic-pyruvic transaminase activities of 66 adult cancer inpatients (aged 22–70 years) were determined both before and after one or two chemotherapy regimens. The percentage of hepatoma patients with abnormal blood fibrinogen levels (< 1.5 or > 6.0 g/l) was higher (64.3% of 14 patients) than that in other cancer categories (19.2% of 52 patients). The mean blood fibrinogen concentrations of male (3.5 g/l) and female (4.5 g/l) cancer patients were higher than those previously reported for healthy humans (2.8 and 2.9 g/l, respectively). After chemotherapy, blood fibrinogen concentrations decreased in patients whose primary tumours were surgically removed (from 4.8 to 3.2 g/l) but increased (from 3.0 to 4.8 g/l) in those who did not undergo surgery. Glutamic-pyruvic transaminase activities did not appear to be related to blood fibrinogen levels. We conclude that the increase in mean blood fibrinogen levels of cancer patients is probably related to tumour growth. Different mechanisms may operate in patients with hepatoma.

A new oxidation method, chemical oxidation under hydrothermal conditions, is introduced to insert oxygen into La2CuO4 compounds. X-ray powder diffraction and magnetic susceptibility measurements show that the oxidized La2CuO4+δ with orthorhombic space group becomes a superconductor with a superconducting transition up to 42 K, which indicates the method is effective in inserting oxygen into La2CuO4. In addition, the oxidation mechanism and the unique properties of the closed system are discussed.

The nuclear and magnetic structures of La-2(Co1-xFex)(16)Ti have been studied by neutron powder diffraction for the compositions x=0.0,0.2,0.4. The compound crystallizes with the symmetry of space group m. Site occupancy results show significant departures from a purely statistical distribution, with the Ti atoms located in sites which interact weakly with La, and with the Co atoms occupying preferentially the sites with strong La interaction. These results are consistent with the enthalpies of formation of equiatomic alloys of rare earth and 3d elements. The spin ordering at all compositions and temperatures is ferromagnetic. At room temperature the moments are aligned along the c axis for the compositions x=0.0 and x=0.2, and form an angle of about 57 degrees with c for x=0.4. This tilt angle is a function of temperature and the moment is aligned along c at 11 K, moving gradually towards the a,b plane as the temperature increases. (C) 1999 American Institute of Physics. [S0021-8979(99)06015-6].

With the velocity de-projection technique, we derived the averaged 3 dimensional local velocity distribution using only the line-of-sight velocity for the 200,000 FGK type main-sequence stars from the LAMOST DR1 data. Taking the effective temperature as a proxy for age, we investigate the variation of the velocity distribution as a function of Teff and disk height within 100 < |z| < 500 pc. Using the mean velocities of the cool stars, we derive the solar motion of (U⊙, V⊙, W⊙)=(9.58±2.39, 10.52±1.96, 7.01±1.67) kms−1 with respect to the local standard of rest (LSR). Moreover, we find that the stars with Teff > 6000 K show a net asymmetric motion of 〈U〉~2 kms−1 and 〈W〉~3 kms−1 compared to the stars with Teff < 6000 K. And their azimuthal velocity increases when |z| increases. The asymmetric motion in the warmer stars is likely because they are too young and not completely relaxed.

Microhardness measurements have been performed on porous silicon (PSi) films. The dependence of the hardness on porosity, morphology and the underlying silicon substrate has been established. A model which determines the intrinsic film hardness has been developed and experimentally validated. The load dependence of hardness was measured as an index of the disorder in porous silicon. Hardness analysis also provided information on the nature of the PSi surface. Finally, several PSi-polymer nanocomposites have been fabricated and characterized. An improvement in hardness is observed, with no apparent change in the PL characteristics.

Currently, it has not yet a good solution to rational and effective seismic response spectrum and ground motion of engineering site with inclined bedrock in engineering practice. Using numerical simulation method of decoupled near-field wave propagation, seismic response of engineering site with inclined bedrock, when δ pulse wave and artificial ground motion are inputted into this two-dimensional model, are analyzed and discussed, the results show that, 1) By the weighted average method of strong motion response spectrum of the left and the right in one-dimensional model, seismic response of engineering site with inclined bedrock can be approximately obtained, but the coefficient factor α is get from the trial, the error and adjustment for many times through the results of two-dimensional model. 2) For SV wave seismic action, the seismic response results of two-dimensional model have significant and obvious wave-type conversion phenomenon, which cannot be solved in one-dimensional model with SH wave as input. 3) Soft soil characteristics of twodimensional model sometimes reflect isolation effect, weakening effect and soft soil damping energy. In short, to solve this issue, two-dimensional model including tilt and inclined bedrock medium, rather than using the left and the right one-dimensional model, are recommended and suggested.

Earthquake-triggered landslide has drawn much attention in the world because of severe hazards it causes. The Ms =7.0 Lushan earthquake which occurred on 20 April 2013, China, in the Longmen Shan mountain region triggered more than 1000 landslides and really blocked many roads and exacerbated the overall transportation problems in the mountainous region. Preliminary landslides inventory is complied based on the high-resolution remote sensing images. Based on it, landslides spatial distribution characteristics and correlations between the occurrence of landslides with geologic and geomorphologic conditions are analyzed. Statistic analysis is conducted by using landslide point density (LPD), which is defined as the number of landslides per square kilometer. It is found that LPD have strong positive correlations with slope gradients, and the landslides are likely to occur in younger strata systems like Quaternary and Tertiary sediments. Spatially, the triggered landslides are controlled by the causative faults in their distribution and mainly concentrate around the epicenter. All the landslides are located within the area with seismic intensity ≥ VII and in scale with the seismic intensity. LPD decreases with increasing distance from the epicenter, and sometimes landslides are found densely presented along the roads in the mountainous. It is found that the empirical distance–magnitude relation are more suitable for estimating the landslides concentrated area during the Lushan earthquake.

In view of the ever expanding research and development in the wireless area, recent advances and topical applications of a computational electromagnetics (CEM) platform are highlighted within this paper. In particular related to the simulation and optimization of complex industrial scenarios, CEM tools must provide outstanding performance with respect to user-friendliness, accuracy, robustness and computation speed. On the basis of optimizing a wireless power transfer system in interaction with a human body, the capabilities of the investigated CEM platform are demonstrated. The outlined feature range encompasses numerical/experimental body phantoms, LF and RF solvers as well as the latest achievements in GPU high performance computing (HPC).

Summary form only given. While contact-less power charging is becoming a popular feature in modern electronic devices, the exposure to a nearby user from a wireless power transfer (WPT) system should be assessed prior to the commercial availability of such systems. In this study, a 4-link 100 kHz magnetically resonant low power wireless charging system is investigated with respect to the exposure of a user hand. Numerical dosimetry techniques are employed to compute the peak induced spatially averaged electric field (E-field) and specific absorption rate (SAR) in a high-resolution anatomically realistic hand model (based on an adult male hand). The computed peak values are analyzed with respect to the exposure limits recommended by the ICNIRP and IEEE exposure guidelines and standards (i.e., ICNIRP-2010, IEEE C95.6-2002 and IEEE C95.1-2005) to determine the compliance of the investigated WPT system and to derive the critical system parameters which could be adjusted to improve the design of a WPT system. A generic coil analysis is conducted by modelling a single circular coil with diameter in the range of 40 to 240 mm. An anatomical hand model, discretized with a uniform 1 mm grid resolution, is placed 1 mm above the coil with the center of the palm facing the center of the coil. The peak spatially averaged E-field (volume averaged for ICNIRP and line averaged for IEEE) values are plotted with the peak SAR (averaged over 1 gram or 10 gram) values to derive the transition frequency, above which, the peak spatial SAR becomes more dominant than the peak induced E-field for an exposure compliance assessment. This transition frequency can be regarded as the optimum operating frequency which leads to the highest output power of a WPT system with respect to the relevant exposure limits. Subsequently, the 4-link 100 kHz WPT system is modelled to facilitate the exposure analysis of an actual wireless charging system. This study provides the frequency-dependent user hand exposure characteristics of a generic circular coil and the exposure analysis of a practical wireless charging system. The computational results indicate that the optimum operating frequency of a WPT system with coil dimensions in the range of 40 mm to 240 mm diameter is approximately 1 MHz based on the peak 2×2×2 mm3 volume averaged E-field and 10 gram averaged SAR values. The investigated 4-link 100 kHz WPT system is found to be compliant with the ICNIRP and IEEE exposure limits while operating with a 5W output power.

57Co was produced with high pure nature iron irradiated by 8.5MeV deuterons. TBP-benzene extraction method and anion-exchange method were used to separate and purify it. The purified57Co was prepared into standard solution of about 30 to 50 μg Co2+/ml carrier concentration and about 0.1 mol/l HCl. The specific activity of the standard solution was measured with 4 π β (ppc)-γ coincidence counting method. The final result was 476.82(1±0.42%)Bq/mg.

We report observation of photoinduced electron transfer between two n-conjugated polymers in binary mixtures. Picosecond transient absorption and fluorescence spectroscopies of mixtures of n-type (electron accepting) poly (benzimidazobenzophenanthroline ladder) (BBL) and p-type (electron donating) poly (p- phenylene benzobisthiazole) (PBZT) or poly(p-(2-hydroxy)-phenylene berizobisoxazole) (HPBO) evidence intermolecular electron transfer when BBL is selectively photoexcited. The results suggest that blends of n-conjugated polymers are supramolecular materials which have novel features such as delocalized radical ion pairs or diion pairs, - novel properties, and- implications for organic p-n junction devices, photodiodes, photovoltaic cells, photoreceptors, and molecular electronic devices.

The magnetostrictive properties and microstructure of Tb 0.27 Dy 0.73 Fe 2 B x ( x =0, 0.05, 0.1, 0.15, 0.2) have been investigated. Measurement of magnetic properties, X-ray diffraction and magnetostriction were made on Tb 0.27 Dy 0.73 Fe 2 B x polycrystalline samples prepared by arc melting. With the increase of boron content x , the iron-rich phase which leads to the detriment of magnetostrictive properties, decreases. The matrix phase of these alloys also has the MgCu 2 structure. The lattice constant and Curie transition temperature change only slightly. The doping of boron in the Tb 0.27 Dy 0.73 Fe 2 alloy can restrain the emergence of the iron-rich phase. The peritectic region probably shifts slightly with the addition of boron.

Both visfatin and polycystic ovary syndrome (PCOS) were previously reported to be in relation to abnormal glucose metabolism (AGM). The hypothesis was investigated in this paper that plasma visfatin level are elevated in Chinese women with PCOS, and could substitute oral glucose tolerance test (OGTT) as a simple predictor for their glucose intolerance. This cross-sectional study enrolled 119 women (91 newly diagnosed PCOS patients and 28 eumenorrheic age- and BMI- matched controls); anthropometric, hormonal, and metabolic parameters including serum visfatin were simultaneously measured in all participants. Plasma visfatin levels were compared between controls and PCOS subjects with various glucose metabolism status diagnosed by OGTT using 75 g of glucose. Pearson correlation coefficients were calculated to determine the correlations between various parameters. Receiver Operating Characteristic (ROC) analysis was performed to examine the diagnostic test performance of visfatin. Plasma visfatin levels were found to be significantly higher in our PCOS population compared to healthy controls (P less than 0.05). An increase in fasting visfatin concentrations with a worsening degree of glucose intolerance among PCOS patients was described. However, the difference did not reach statistical significance. In addition, visfatin was unexpectedly found to correlate with neither age, anthropometric, hormonal nor metabolic parameters. As a predictor for glucose intolerance to distinguish PCOS individuals with normal or abnormal glucose metabolism, visfatin was found to possess low potentially predictive ability according to ROC curve analysis. In conclusion, serum visfatin is significantly elevated in Chinese women with PCOS, but might not be a reliable predictor of their glucose intolerance.

In light of the ever expanding research field of electromagnetic related studies, a simulation platform which is capable of solving multidisciplinary electromagnetic problems is indispensable. While dealing with challenging wireless product design or electromagnetic exposure safety assessment, numerical simulation can often provide insightful information which cannot be achievable by the current measurement techniques. The aim of this paper is to review the applications of numerical techniques in various electromagnetic-related research fields and to reveal the distinct advantages of employing state-of-the-art computational approaches.

The objective of this study is to investigate the near field coupling between a miniature loudspeaker and a nearby antenna. The analysis focuses on the loudspeaker voice coil radio frequency resonance characteristics and antenna radiation efficiency degradation due to the presence of the loudspeaker. Both measurement and simulation results are given to assess the impact of a loudspeaker when it is placed in close proximity with a monopole antenna mounted on a printed circuit board. This study leads to a better understanding to achieve optimum antenna-loudspeaker integrated module design for mobile devices.

New iron selenide superconductors by intercalating smaller-sized alkali metals (Li, Na) and alkaline earths using high-temperature routes have been pursued ever since the discovery of superconductivity at about 30 K in KFe₂Se₂, but all have failed so far. Here we demonstrate that a series of superconductors with enhanced T(c) = 30∼46 K can be obtained by intercalating metals, Li, Na, Ba, Sr, Ca, Yb, and Eu in between FeSe layers by the ammonothermal method at room temperature. Analysis on their powder X-ray diffraction patterns reveals that all the main phases can be indexed based on body-centered tetragonal lattices with a∼3.755-3.831 Å while c∼15.99-20.54 Å. Resistivities show the corresponding sharp transitions at 45 K and 39 K for NaFe₂Se₂ and Ba₀.₈Fe₂Se₂, respectively, confirming their bulk superconductivity. These findings provide a new starting point for studying the properties of these superconductors and an effective synthetic route for the exploration of new superconductors as well.

We presented our investigations on the absorption and emission properties of the nanocrystalline ZnO particles of different particle sizes (2 nm-5 nm) by sol-gel method. In the room temperature PL spectra, three emission bands, ultraviolet (UV), blue and green were observed. With increasing the particle sizes, both the UV and the visible emission bands shifted to lower energies progressively. From the size-dependency, there was a linear relationship between the energetic maxima of the UV and the green emission bands with a slope of about 0.26, which indicated that the green luminescence of ZnO was produced by the transitions of electrons from deep level to the valence band (or shallow acceptor level). A linear dependence was also found between the energetic maxima of the UV and the blue emissions with a slope of 0.15, the origin this blue emission band is not clear at present. While in van Dijken et al.'s paper, however, they identified only two emission bands in the emission spectra, an UV and a broad visible emission band, and the linear fit between the energetic maxima of these two bands in particles of different sizes has a slope of 0.6, so they proposed that the visible emission in ZnO was originated from the recombination of a shallowly trapped electron with a deeply trapped hole. We attributed this divergence to the fact that the broad visible band is actually composed of two separate emission bands originated from two different recombination processes, and should not had been treated as one emission band.

The performance of a GPS antenna (inverted-F) design is investigated when the tracking device is placed on flat torso and dog-shaped phantoms. A prototype of the device is constructed to validate the proposed antenna design in free space condition with both measurement and simulation. Following that, the effects of body loading to the antenna are examined through numerical simulations to achieve an optimum orientation of the device with respect to the actual operating condition (with body loading). The results from this study indicate that the radiation/reception characteristics of a small GPS antenna can be very different between free space and body loading conditions. In order to achieve the best antenna performance, the body loading effect should be closely examined.

With the increasing popularity of wireless capability of contemporary electrical devices, the demand for small and efficient antenna design is also on the rise. This paper presents the design and implementation of a miniature antenna for Wi-Fi enabled Secure Digital (SD) card to be used in a digital camera. The challenges faced in the design of such antenna are the limited antenna volume and the severe loading from nearby metallic structures. The design is optimized using simulation tool prior to prototype modeling and measurement. Antenna efficiency of 38% is achieved in actual operating environment when the memory card is placed inside a camera.

A simplified set of three‐dimensional equations are derived for the propagation of an intense laser pulse of arbitrary strength a=eA/mc2 (where A is the magnetic vector potential of the laser pulse) in cold underdense plasma. In different limits, the equations can be easily reduced to those of previous one‐dimensional models [Phys. Fluids 30, 526 (1987); Phys. Rev. A 40, 3230 (1989); 41, 4463 (1990)]. For ‖a‖≤1, an approximate set of equations from the averaged Lagrangian is obtained. The present study differs from previous work in that wave dispersion is also important for short laser pulse, and is included in the model equations. The axisymmetric two‐dimensional model equations are solved numerically to show the effect of dispersion in the self‐focusing process.

ZnO nanorods with diameters of 10–200 nm were fabricated through a simple gas reaction method. They were characterized by means of powder X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray (EDX) spectroscopy and transmission electron microscopy (TEM). FE-SEM and TEM images showed that the product was composed of nanorods with lengths from several to tens microns. XRD and EDX indicated that the nanorods were hexagonal ZnO.

Three kinds of GaN samples (hexagonal coarse-grain powders, hexagonal nanoparticles and cubic nanoparticles) were synthesized by different methods. The room-temperature frequency spectra of the relative dielectric constant and that of the dielectric loss were measured in the frequency range of 100 Hz to 10 MHz. Analysis of these spectra indicates that the grain size of samples has great influence on the dielectric behavior of samples whereas the crystallography symmetry almost has no impact on the relative dielectric constant.

We have performed an angle-resolved photoemission spectroscopy study of the new iron-based superconductor K(0.8)Fe(1.7)Se(2) (T(c)∼30 K). Clear band dispersion is observed with the overall bandwidth renormalized by a factor of 2.5 compared to our local density approximation calculations, indicating relatively strong correlation effects. Only an electronlike band crosses the Fermi energy, forming a nearly circular Fermi surface (FS) at M (π, 0). The holelike band at Γ sinks ∼90 meV below the Fermi energy, with an indirect band gap of 30 meV, to the bottom of the electronlike band. The observed FS topology in this superconductor favors (π, π) inter-FS scattering between the electronlike FSs at the M points, in sharp contrast to other iron-based superconductors which favor (π, 0) inter-FS scattering between holelike and electronlike FSs.

This paper investigates the electric field and current density induced in a human body when exposed to low frequency electromagnetic fields. A numerical technique based on the Finite Element Method and electromagnetic quasistatic approximations is employed to compute both the fields generated by low frequency sources and the fields induced inside a human body due to exposure or contact. Case study is conducted to investigate exposure situations pertaining to the safety of human being in the vicinity of high intensity low frequency electromagnetic fields.

In this study, Genetic Algorithms (GA) [1] in conjunction with network parallelization technique are utilized for the design and optimization of mobile phone antennas in a CAD derived environment. On the basis of a commercial mobile phone CAD model, three types of internally embedded multi-band antenna are designed and optimized within a fixed volume. Through the use of network parallelization, optimization time can be significantly reduced.

The isothermal section at 700 degrees C in the Co-rich ternary Sm-Co-B system was determined by means of X-ray diffraction. In this range, nine ternary borides were observed: Sm3Co13B2, SmCo4B, Sm3Co11B4, Sm2Co7B3, SmCo3B2, Sm2Co14B, SmCo12B6, SmCo4B4, SmCo2B2. The first five borides are members of the homologous series Smm + nCo5m + 3nB2n formed by alternative stacking m layers of SmCo5 with n layers of SmCo3B2 along the c-axis. The compound Sm3Co13B2 was not reported in previous isothermal sections found in the literature. (C) 2000 Elsevier Science S.A. All rights reserved.

In this paper, the subsolidus phase relations of the ternary system MgO-Ga2O3-B2O3 were investigated. There are five binary compounds and one ternary compound. The ternary phase diagram consists of eight ternary phase regions. The ternary compound, GaMgBO4, is isostructural to Y2BeO4. It crystallizes in the orthorhombic system with the space group Pnam and lattice parameters a=9.1847(1) Angstrom, b=9.2942(1) Angstrom, c=3.0779(1) Angstrom, Z=4 and rho (cal.) = 4.267 g/cm(3). The Mg2+ and Ga3+ ions are distributed between the two cation sites: 77.8% Ga3+ and 22.2% Mg2+ occupy the cation site I, others (22.2% Ga3+ and 77.8% Mg2+) occupy the cation site II. In this structure the Mg2+ and Ga3+ ions are surrounded octahedrally by oxygen atoms, the berate ion is a single triangle (BO3). The most important feature of this structure is the way these octahedra are linked together by sharing edges to form ribbons, which are one octahedron thick and four octahedra wide in the ab plane and extend infinitely along the direction of the c axis. The XRD results show no phase transition occurs between -173 degreesC and 227 degreesC. The lattice parameters and the volume expansion coefficient were calculated. (C) 2001 Elsevier Science B.V. Al rights reserved.

Phase relations of the ternary system SrO-TiO2-B2O3 have been investigated by X-ray powder diffraction (XRD). This system can be divided into eight three-phase regions. Seven binary compounds are observed in this system, which are SrTiO4, Sr3Ti2O7, SrTiO3,, Sr3B2O6, Sr2B2O5, SrB2O4, SrB4O7, but no ternary compound is found. The Rietveld refinement method was used to determine the structure of the compound Sr3B2O6 and found it to be calcium-orthoborate structure. The cell parameters are determined to be a=b=9.0405(2) Angstrom, c=12.5665(2) Angstrom, and Sr. B, and O occupy the 18e. 12c, 36f positions, respectively. (C) 2001 Elsevier Science B.V. All rights reserved.

The subsolidus phase relations of the system Y2O3 -CaO-B2O3 are investigated by means of X-ray diffraction (XRD) analyses. There are six binary compounds and three ternary compounds in this system. The phase diagram comprises 13 three-phase regions. The ternary compound CaYBO4 is refined from powder XRD data by the Rietveld method. It has a warwickite-like structure with cell parameters a=10.4354(3) Angstrom, b=9.6126(2) Angstrom, c=3.5880(1) Angstrom and space group Nam. The rationality of the CaYBO4 structure is examined by Brown bond valence model and IR spectra. (C) 2001 Elsevier Science BY. All rights reserved.

The structure of Na2Al2B2O7 has been refined on X-ray powder diffraction data collected in transmission mode by Rietveld techniques because the polycrystalline samples exhibit a strong tendency of preferred orientation and the single crystals are of poor quality. Final refinement on powder diffraction data converged to agreement factors R-p=6.54%, R-wp=8.55% with R =5.24%. The title compound crystallizes in a trigonal space group P-31c. Lattice parameters are refined to be a=4.8113(1) Angstrom and = 15.2781(3) Angstrom. The structure consists of infinite [Al2B2O7](x) sheets stacking along c-axis and Na atoms in both the inter-sheets and intra-sheets. Infrared spectra of both Na2Al2B2O7 and Na2Ga2B2O7 are reported and a brief interpretation is given based on the structures. High quality X-ray powder diffraction data and results of thermal analysis are also presented. (C) 2001 Elsevier Science B.V. All rights reserved.

The crystal structure of the compound Ca3La3(BO3)(5) refined from powder XRD data has space group P6(3)mc with cell parameters a = 10.5319(3) Angstrom, c = 6.4077(1) Angstrom and z = 2. The structure consists of a three-dimensional network made up of BO3 triangles as well as irregular oxygen polyhedra of lanthanum and calcium atoms. The infrared spectra (IR) of this Compound have been investigated and confirm that the boron atoms have three-fold coordination. Differential thermal analysis (DTA) revealed that a reversible decomposition reaction takes place in Ca3La3(BO3)(5) at 1165 degreesC and it completely melts above 1300 degreesC. (C) 2001 Elsevier Science B.V. All rights reserved.

The Na 2 O-rich portion of the ternary diagram Ln 2 O 3 –Na 2 O–B 2 O 3 (Ln=Y, Gd) has been investigated. A ternary phase of composition Na 3 Ln(BO 3 ) 2 has been found for Ln=Y, Gd. These compounds crystallize in the monoclinic space group P2 1 /c . The structure has been determined for the compound Na 3 Y(BO 3 ) 2 from powder X-ray diffraction. The structure can be described as being made up of isolated BO 3 triangles held together by the yttrium and sodium ions. The yttrium atoms have seven-fold coordination in a covalent BO 3 matrix. The sodium atoms have seven-, six- and four-fold coordination.

The measurement of plant root growth is important in gauging the effect of experimental changes (nutrients, illumination, orientation, etc) made to plants. The most commonly used software is a combination of the common optical flow measurement method of Horn and Shunk with a ruggedized backward forward block matching method. The best results for this method show a low reliability for the optic flow measurement (less than 5%) and mostly rely on the ruggedized backwards forwards block matching. The current paper demonstrates that by correct tuning of the aperture a scale space based optical flow measurement can produce a higher reliability than the former tensor method. In addition, when the output of the scale space optical flow measurements are used to constrain the search space of the block matching method a still higher reliability is achievable. Systematic errors introduced by the forward backward matching with a non-optimally constrained search space are also eliminated.

This paper investigates the electric field and current density induced in a human body when exposed to low frequency electromagnetic fields. A numerical technique based on the Finite Element Method and electromagnetic quasistatic approximations is developed to compute both the fields generated by low frequency sources and the fields induced inside a human body due to direct or indirect exposure scenarios. A case study is conducted to investigate exposure situations pertaining to the safety of human beings in the vicinity of high intensity low frequency electromagnetic fields.

In this article, the virtual prototyping of mobile phone antennas is demonstrated with a FDTD-based electromagnetic simulation platform powered with GPU hardware acceleration. Through network parallelization and Generic Algorithms, antenna optimizations can be performed concurrently on multiple workstations. The simulation time required for an optimization task is reduced proportionally by the number of workstations utilized. The optimization features are demonstrated on a commercial mobile phone model, through the virtual prototyping process, different antenna designs can be optimized targeting multiple goals and operating scenarios. The numerical technique is proven to be efficient and effective for RF design optimization tasks.

The interaction of two near‐marginal tearing modes in the presence of shear flow is studied. To find the time asymptotic states, the resistive magnetohydrodynamic (MHD) equations are reduced to four amplitude equations, using center manifold reduction. These amplitude equations are subject to the constraints due to the symmetries of the physical problem. For the case without flow, the model that is adopted has translation and reflection symmetries. Presence of flow breaks the reflection symmetry, while the translation symmetry is preserved, and hence flow allows the coefficients of the amplitude equations to be complex. Bifurcation analysis is employed to find various possible time asymptotic states. In particular, the oscillating magnetic island states discovered numerically by Persson and Bondeson [Phys. Fluids 29, 2997 (1986)] are discussed. It is found that the flow‐introduced parameters (imaginary part of the coefficients) play an important role in driving these oscillating islands.

β-Ga 2 O 3 nanorods with diameters of 10–60 nm were synthesized through a simple gas reaction method and were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), selected area electron diffraction (SAED) and high-resolution transmission electron microscopy (HRTEM). The SEM image showed that most of the nanorods were straight. XRD, SAED and HRTEM indicated that the nanorods were monoclinic Ga 2 O 3 single crystals.

The isothermal section at 700 degrees C in the Co-rich ternary Sm-Co-B system was determined by means of X-ray diffraction. In this range, nine ternary borides were observed: Sm3Co13B2, SmCo4B, Sm3Co11B4, Sm2Co7B3, SmCo3B2, Sm2Co14B, SmCo12B6, SmCo4B4, SmCo2B2. The first five borides are members of the homologous series Smm + nCo5m + 3nB2n formed by alternative stacking m layers of SmCo5 with n layers of SmCo3B2 along the c-axis. The compound Sm3Co13B2 was not reported in previous isothermal sections found in the literature. (C) 2000 Elsevier Science S.A. All rights reserved.

To access the feasibility of using cultivated oral mucosal epithelial cell transplantation (COMET) for the management of severe corneal burn.COMET was performed to promote re-epithelialization in two eyes with acute alkaline burn and one eye with chronic alkaline burn, and to reconstruct the ocular surface in two eyes with chronic thermal burn. Autologous oral mucosal epithelial cells obtained from biopsy were cultivated on amniotic membrane. Immunoconfocal microscopy for keratins and progenitor cell markers was performed to characterize the cultivated epithelial sheet. Following transplantation, the clinical outcome and possible complications were documented. The patients were followed for an averaged 29.6+/-3.6 (range: 26-34) months.Cultivated oral mucosal epithelial sheet expressed keratin 3, 13, and progenitor cell markers p63, p75, and ABCG2. After COMET, all the corneas became less inflamed, and the corneal surface was completely re-epithelialized in 6.0+/-3.2 (range: 3-10) days in all but one patients. Microperforation occurred in one patient, and a small persistent epithelial defect developed in another. Both were solved uneventfully. In all patients, superficial corneal blood vessels invariably developed, and to further improve vision, conjunctivo-limbal autografting (N=3) and/or penetrating keratoplasty (N=3) were performed subsequently. The vision of all patients showed substantial improvement after additional surgeries.This study showed the potential of COMET to promote re-epithelialization and reduce inflammation in acute corneal burn, and to reconstruct the corneal surface in chronic burn. COMET may, therefore, be considered an alternative treatment for severe corneal burn.