bluuebunny/crossref_metadata_2025 huggingface dataset:
Magnetic optical sensor particles: a flexible analytical tool for microfluidic devices
Authors: Ungerböck Birgit , Fellinger Siegfried , Sulzer Philipp , Abel Tobias , Mayr Torsten
Published: February 2014

Magnetic optical sensor particles are used to generate in situ sensor spots within microfluidic channels and serve as flexible analytical tools.
Quantification of total serum transferrin and transferrin sialoforms in human serum; an alternative method for the determination of carbohydrate-deficient transferrin in clinical samples
Authors: Ordonez Yoana Nuevo , Anton Raymond F. , Davis W. Clay
Published: February 2014

Carbohydrate deficient transferrin (CDT) is a biochemical marker for congenital disorders of glycosylation (CDG), chronic alcohol consumption, and forensic medicine diagnosis.
Rhodium-catalyzed synthesis of unsymmetrical di(aryl/heteroaryl)methanes using aryl/heteroarylmethyl ketones via CO–C bond cleavage
Authors: Li Guangzhe , Arisawa Mieko , Yamaguchi Masahiko
Published: February 2014

The RhH(PPh3)4 complex catalyzes the reaction of aryl/heteroarylmethyl ketones and aryl heteroaryl ethers giving unsymmetrical diarylmethanes containing one or two heteroarenes.
Controllable synthesis of Ni nanotube arrays and their structure-dependent catalytic activity toward dye degradation
Authors: Li Xiang-Zi , Wu Kong-Lin , Ye Yin , Wei Xian-Wen
Published: February 2014

Ni nanotube (nanorod) arrays are controllably fabricated by a one-step approach, the GDDATG and DDCG growth mechanisms are introduced. The Ni nanostructures present higher catalytic activities for dye degradation, the relationship between structures and catalytic properties is also studied.
An induced-fit process through mechanical pivoting of aromatic walls in host–guest chemistry of calix[6]arene aza-cryptands
Authors: Brugnara Andrea , Fusaro Luca , Luhmer Michel , Prangé Thierry , Colasson Benoit , Reinaud Olivia
Published: February 2014

A rigid calix[6]arene-based receptor can be fullyipso-nitrated. The nitrated receptor exhibits a new adaptive behavior upon cation and/or guest encapsulation.
A flexible electrode based on a three-dimensional graphene network-supported polyimide for lithium-ion batteries
Authors: Meng Yuena , Wu Haiping , Zhang Yajie , Wei Zhixiang
Published: February 2014

A flexible composite electrode as a cathode for lithium batteries is produced by compositing a three-dimensional graphene network and vertically aligned polyimide nanoflakes.
Effect of a micro dielectric barrier discharge plasma actuator on quiescent flow
Authors: Pescini Elisa , De Giorgi Maria Grazia , Francioso Luca , Sciolti Aldebara , Ficarella Antonio
Published: February 2014

A dielectric barrier discharge plasma actuator (PA) was designed and manufactured with microscale dimensions using photolithographic process on fibre glass substrate. AC operation under sinusoidal voltage was investigated experimentally by means of electrical characterisation, smoke flow visualisations and particle image velocimetry. The performances of the micro PA were evaluated and compared with the ones of a macro PA found in this literature. The velocity induced by the micro PA was comparable with the macro PA one, but with lower applied voltage, electrical power dissipation and actuator size. This is particularly interesting for potential applications in turbomachinery.
Two‐dimensional measurements of primary soot diameter in diffusion flames by two‐dimensional time resolved laser induced incandescence
Authors: Potenza Marco , Naccarato Fabrizio , de Risi Arturo
Published: February 2014

Two dimensions primary soot diameter calculation in a laminar diffusion liquid petroleum gas flame by means of laser induced incandescence (LII) is presented in present paper. LII is a high sensitive technique in which a high energy Nd‐Yag laser sheet heats soot particles up to a temperature of about 4000 K but without exceeding the sublimation temperature. Radiation from exited soot particles is acquired by means of an intensified coupled charge device (CCD) camera (low gate opening time of 10 ns) synchronised with the laser pulse. By delaying the acquisition time with respect to laser pulse, LII signal decay as function of time has been reconstructed. Performing acquisition at two different wavelengths by means of two interferometric filters (two colour LII) a soot temperature behaviour (related to particles primary diameter) has been calculated. For quantitative measurements of the soot volume fraction a tungsten lamp calibration method for optics was used. Using laser fluence and self‐absorption corrections for LII signal, bi‐dimensional quantitative measurements can be achieved for soot dimensions and distribution. By means of a flame centre‐of‐mass alignment on the corrected images for different time steps, it is possible to achieve the soot decay curve for each pixel of the images, performing a two‐dimensional (2D) soot primary particles visualisation.
Treatment Effects of Dexmedetomidine and Ketamine on Postoperative Analgesia after Cleft Palate Repair
Authors: Kayyal Talal A. , Wolfswinkel Erik M. , Weathers William M. , Capehart Samantha J. , Monson Laura A. , Buchanan Edward P. , Glover Chris D.
Published: February 2014

Primary cleft palate repair may result in significant pain in the immediate postoperative period, which can lead to vigorous crying resulting in wound dehiscence and pulmonary complications. Effective pain control with opioids is the mainstay but administration on the floor has to be countered with the complications associated with their use, chiefly respiratory depression and sedation. We retrospectively examined the efficacies of intraoperative administration of intravenous (IV) dexmedetomidine (DEX) and ketamine (KET) to prevent early postoperative pain in children undergoing primary cleft palate repair and compared the results against relevant literature. The Texas Children's Hospital anesthesia database was queried to identify children undergoing a palatal surgery from December 2011 to December 2012. Inclusion criteria permitted completed primary palatal surgery without major complications and intraoperative administration of DEX or KET. The control group (CTRL) received no additional drug. A comprehensive literature review was performed. A total of 71 pediatric patients underwent palatal surgery during the study period with 46 patients qualifying for analysis. Although results were not significant, consistent trends were observed with regards to lower opioid requirements during the first 24 hours for both medications compared with the CTRL. KET also had shorter time to discharge. The literature review resulted in several studies supporting decreased postoperative pain end points for both DEX and KET. In our sample, DEX and KET reduced postoperative opioid requirements. KET seems to have the added benefit of a shorter hospital stay. These finding are supported in the literature. With further investigation, the addition of these drugs may serve to provide improved pain relief without over sedation in patients undergoing cleft palate repair.
Molecular Orbital Study of Be4
Authors: Cloney Robert D. , Dooling John S.
Published: February 2014

An LCAO MO SCF study was made of the square, planar Be4 complex. A complete SCF calculation was performed at four different internuclear distances. In this series of calculations all one- and two-center integrals were evaluated exactly and the value of each three- and four-center integral was estimated by a method considered most suitable for it. The results showed the complex unstable. The energy values when extrapolated to infinite internuclear distance were in good agreement with experiment. A second series of calculations was made to determine the effect of three- and four-center integral approximations on the energies. Here all the multicenter integrals were evaluated by one type of approximation. This introduced a relatively small change in the integral values, but large changes in the energies. The study emphasizes the need for exact values of three- and four-center integrals before exact calculations can be undertaken.
Calculation of Line Widths in H2O-N2 Collisions
Authors: Benedict W. S. , Kaplan L. D.
Published: February 2014

Anderson’s general theory of collision line broadening has been applied to H2O-N2 encounters. The only attractive force was assumed to be that between the H2O dipole, μ = 1.87×10−18 esu, and the N2 quadrupole, qN2, an adjustable parameter. A second adjustable parameter, bm, the distance of closest approach, includes the effects of all other forces. The IBM 704 was used in the calculation. Effects of varying the parameters were noted for a number of lines, and in the final calculation, which yielded the widths of all significant type B transitions up to J″ = 13, parameters qN2 = 2.62×10−26 esu and bm = 3.2 A which give an exact fit of the observed width of the microwave line 6−5−5−1, were adopted. The temperature dependence of the line width over the range 220–2400 °K, and the effects of vibration-rotation interactions were also calculated. At 300 °K widths vary from 0.11115 cm−1 atmos for 11−1−1 to 0.03200 cm−1 atmos−1 for 14−13−13−13, there being a general decrease in width with increasing J, and at a given J, decreasing width with increasing τ.
Upper bounds for flexoelectric coefficients in ferroelectrics
Authors: Yudin P. V. , Ahluwalia R. , Tagantsev A. K.
Published: February 2014

Flexoelectric effect is the response of electric polarization to the mechanical strain gradient. At the nano-scale, where large strain gradients are expected, the flexoelectric effect becomes appreciable and may substitute piezoelectric effect in centrosymmetric materials. These features make flexoelectricity of growing interest during the last decade. At the same time, the available theoretical and experimental results are rather contradictory. In particular, experimentally measured flexoelectric coefficients in some ferroelectric materials largely exceed theoretically predicted values. Here, we determine the upper limits for the magnitude of the static bulk contribution to the flexoelectric effect in ferroelectrics, the contribution which was customarily considered as the dominating one. The magnitude of the upper bounds obtained suggests that the anomalously high flexoelectric coupling documented for perovskite ceramics can hardly be attributed to a manifestation of the static bulk effect.
Opacity and gradients in aluminum wire array z-pinch implosions on the Z pulsed power facility
Authors: Ampleford D. J. , Hansen S. B. , Jennings C. A. , Jones B. , Coverdale C. A. , Harvey-Thompson A. J. , Rochau G. A. , Dunham G. , Moore N. W. , Harding E. C. , Cuneo M. E. , Chong Y.-K. , Clark R. W. , Ouart N. , Thornhill J. W. , Giuliani J. , Apruzese J. P.
Published: February 2014

Aluminum wire array z pinches imploded on the Z generator are an extremely bright source of 1–2 keV radiation, with close to 400 kJ radiated at photon energies >1 keV and more than 50 kJ radiated in a single line (Al Ly-α). Opacity plays a critical role in the dynamics and K-shell radiation efficiency of these pinches. Where significant structure is present in the stagnated pinch this acts to reduce the effective opacity of the system as demonstrated by direct analysis of spectra. Analysis of time-integrated broadband spectra (0.8–25 keV) indicates electron temperatures ranging from a few 100 eV to a few keV are present, indicative of substantial temperature gradients.
Diffusion-assisted selective dynamical recoupling: A new approach to measure background gradients in magnetic resonance
Authors: Álvarez Gonzalo A. , Shemesh Noam , Frydman Lucio
Published: February 2014

Dynamical decoupling, a generalization of the original NMR spin-echo sequence, is becoming increasingly relevant as a tool for reducing decoherence in quantum systems. Such sequences apply non-equidistant refocusing pulses for optimizing the coupling between systems, and environmental fluctuations characterized by a given noise spectrum. One such sequence, dubbed Selective Dynamical Recoupling (SDR) [P. E. S. Smith, G. Bensky, G. A. Álvarez, G. Kurizki, and L. Frydman, Proc. Natl. Acad. Sci. 109, 5958 (2012)], allows one to coherently reintroduce diffusion decoherence effects driven by fluctuations arising from restricted molecular diffusion [G. A. Álvarez, N. Shemesh, and L. Frydman, Phys. Rev. Lett. 111, 080404 (2013)]. The fully-refocused, constant-time, and constant-number-of-pulses nature of SDR also allows one to filter out “intrinsic” T1 and T2 weightings, as well as pulse errors acting as additional sources of decoherence. This article explores such features when the fluctuations are now driven by unrestricted molecular diffusion. In particular, we show that diffusion-driven SDR can be exploited to investigate the decoherence arising from the frequency fluctuations imposed by internal gradients. As a result, SDR presents a unique way of probing and characterizing these internal magnetic fields, given an a priori known free diffusion coefficient. This has important implications in studies of structured systems, including porous media and live tissues, where the internal gradients may serve as fingerprints for the system's composition or structure. The principles of this method, along with full analytical solutions for the unrestricted diffusion-driven modulation of the SDR signal, are presented. The potential of this approach is demonstrated with the generation of a novel source of MRI contrast, based on the background gradients active in an ex vivo mouse brain. Additional features and limitations of this new method are discussed.
Nucleation near the eutectic point in a Potts-lattice gas model
Authors: Agarwal Vishal , Peters Baron
Published: February 2014

We use the Potts-lattice gas model to study nucleation at and near the eutectic composition. We use rare-event methods to compute the free energy landscape for the competing nucleation products, and short trajectories at the barrier top to obtain prefactors. We introduce a procedure to tune the frequency of semigrand Monte Carlo moves so that the dynamics of a small closed system roughly resemble those of an infinite system. The non-dimensionalized nucleation rates follow trends as predicted by the classical nucleation theory. Finally, we develop corrections that convert free energy surfaces from closed (canonical) simulations into free energy surfaces from open (semigrand) simulations. The new corrections extend earlier corrections to now address situations like nucleation at the eutectic point where two products nucleate competitively.
Generalization of Abel's mechanical problem: The extended isochronicity condition and the superposition principle
Authors: Kinugawa Tohru
Published: February 2014

This paper presents a simple but nontrivial generalization of Abel's mechanical problem, based on the extended isochronicity condition and the superposition principle. There are two primary aims. The first one is to reveal the linear relation between the transit-time T and the travel-length X hidden behind the isochronicity problem that is usually discussed in terms of the nonlinear equation of motion \documentclass[12pt]{minimal}\begin{document}$\frac{{d^2X}}{{dt^2}} + \frac{{dU}}{{dX}} = 0$\end{document}d2Xdt2+dUdX=0 with U(X) being an unknown potential. Second, the isochronicity condition is extended for the possible Abel-transform approach to designing the isochronous trajectories of charged particles in spectrometers and/or accelerators for time-resolving experiments. Our approach is based on the integral formula for the oscillatory motion by Landau and Lifshitz [Mechanics (Pergamon, Oxford, 1976), pp. 27–29]. The same formula is used to treat the non-periodic motion that is driven by U(X). Specifically, this unknown potential is determined by the (linear) Abel transform X(U) ∝ A[T(E)], where X(U) is the inverse function of U(X), \documentclass[12pt]{minimal}\begin{document}$A = (1/\sqrt{\pi })\int _{0}^{E} {dU}/\sqrt{E-U}$\end{document}A=(1/π)∫0EdU/E−U is the so-called Abel operator, and T(E) is the prescribed transit-time for a particle with energy E to spend in the region of interest. Based on this Abel-transform approach, we have introduced the extended isochronicity condition: typically, τ = TA(E) + TN(E) where τ is a constant period, TA(E) is the transit-time in the Abel type [A-type] region spanning X > 0 and TN(E) is that in the Non-Abel type [N-type] region covering X < 0. As for the A-type region in X > 0, the unknown inverse function XA(U) is determined from TA(E) via the Abel-transform relation XA(U) ∝ A[TA(E)]. In contrast, the N-type region in X < 0 does not ensure this linear relation: the region is covered with a predetermined potential UN(X) of some arbitrary choice, not necessarily obeying the Abel-transform relation. In discussing the isochronicity problem, there has been no attempt of N-type regions that are practically of full use for the charged-particle spectrometers and/or accelerators. In this Abel-transform approach, the superposition principle simplifies the derivation of XA(U) satisfying the extended isochronicity condition. Although the extended isochronicity condition inevitably discards the low-energy particles, there is no problem for handling accelerated particles because they do not involve the small-amplitude oscillations around the potential minimum. We present analytic examples of XA(U) that are instructive. In Appendix B, Urabe's criterion is interpreted in the time domain, using the Abel-transform approach.
The virial theorem for the polarizable continuum model
Authors: Cammi R.
Published: February 2014

The electronic virial theorem is extended to molecular systems within the framework of the Polarizable Continuum Model (PCM) to describe solvation effects. The theorem is given in the form of a relation involving the components of the energy (kinetic and potential) of a molecular solute and its electrostatic properties (potential and field) at the boundary of the cavity in the continuum medium. The virial theorem is also derived in the presence of the Pauli repulsion component of the solute-solvent interaction. Furthermore, it is shown that these forms of the PCM virial theorem may be related to the virial theorem of more simple systems as a molecule in the presence of fixed point charges, and as an atom in a spherical box with confining potential.
Activation and deactivation of vibronic channels in intact phycocyanin rods
Authors: Nganou C. , David L. , Meinke R. , Adir N. , Maultzsch J. , Mkandawire M. , Pouhè D. , Thomsen C.
Published: February 2014

We investigated the excitation modes of the light-harvesting protein phycocyanin (PC) from Thermosynechococcus vulcanus in the crystalline state using UV and near-infrared Raman spectroscopy. The spectra revealed the absence of a hydrogen out-of-plane wagging (HOOP) mode in the PC trimer, which suggests that the HOOP mode is activated in the intact PC rod, while it is not active in the PC trimer. Furthermore, in the PC trimer an intense mode at 984 cm−1 is assigned to the C–C stretching vibration while the mode at 454 cm−1 is likely due to ethyl group torsion. In contrast, in the similar chromophore phytochromobilin the C5,10,15-D wag mode at 622 cm−1 does not come from a downshift of the HOOP. Additionally, the absence of modes between 1200 and 1300 cm−1 rules out functional monomerization. A correlation between phycocyanobilin (PCB) and phycoerythrobilin (PEB) suggests that the PCB cofactors of the PC trimer appear in a conformation similar to that of PEB. The conformation of the PC rod is consistent with that of the allophycocyanin (APC) trimer, and thus excitonic flow is facilitated between these two independent light-harvesting compounds. This excitonic flow from the PC rod to APC appears to be modulated by the vibration channels during HOOP wagging, C = C stretching, and the N–H rocking in-plan vibration.
Monte Carlo simulations for the free energies of C60 and C70 fullerene crystals by acceptance ratio method and expanded ensemble method
Authors: Kim Minkyu , Chang Jaeeon , Sandler Stanley I.
Published: February 2014

Accurate values of the free energies of C60 and C70 fullerene crystals are obtained using expanded ensemble method and acceptance ratio method combined with the Einstein-molecule approach. Both simulation methods, when tested for Lennard-Jones crystals, give accurate results of the free energy differing from each other in the fifth significant digit. The solid-solid phase transition temperature of C60 crystal is determined from free energy profiles, and found to be 260 K, which is in good agreement with experiment. For C70 crystal, using the potential model of Sprik et al. [Phys. Rev. Lett. 69, 1660 (1992)], low-temperature solid-solid phase transition temperature is found to be 160 K determined from the free energy profiles. Whereas this is somewhat lower than the experimental value, it is in agreement with conventional molecular simulations, which validates the methodological consistency of the present simulation method. From the calculations of the free energies of C60 and C70 crystals, we note the significance of symmetry number for crystal phase needed to properly account for the indistinguishability of orientationally disordered states.
Onset of laminar separation and vortex shedding in flow past unconfined elliptic cylinders
Authors: Paul Immanuvel , Prakash K. Arul , Vengadesan S.
Published: February 2014

This article presents the numerical studies on predicting onset of flow separation and vortex shedding in flow past unconfined two-dimensional elliptical cylinders for various Axis Ratios (AR) and a wide range of Angles of Attack (AOA). An efficient Cartesian grid technique based immersed boundary method is used for numerical simulations. The laminar separation Reynolds number (Res) that marks separation of flow from surface and the critical Reynolds number (Recr) which represents transition from steady to unsteady flow are determined using diverse methods. A stability analysis which uses Stuart-Landau equation is also performed for calculating Recr. The shedding frequency (Stcr) that corresponds to Recr is calculated using Landau constants. The simulated results for circular cylinder are found to be in good agreement with the literature. The effects of AR and AOA on Res, Recr, and Stcr are studied. It is observed that the Res, Recr, and Stcr exhibit a direct/inverse relationship with AR depending upon the given AOA. Correlations of Res, Recr, and Stcr with respect to AR and AOA are proposed with good accuracy.
Methods for characterizing magnetic footprints of perpendicular magnetic recording writer heads
Authors: Li Shaoping , Lin Ed , George Zach , Terrill Dave , Mendez H. , Santucci J. , Yie Derek
Published: February 2014

In this work, the magnetic footprints, along with some of its dynamic features in recording process, of perpendicular magnetic recording writer heads have been characterized by using three different techniques. Those techniques are the spin-stand stationary footprint technique, the spin-stand dynamic footprint technique, and the coherent writing technique combined with magnetic force microscope imaging method. The characteristics of those techniques have been compared to one another. It was found experimentally that the spin-stand stationary method could not precisely catch some peculiar recording dynamics of the write heads in certain conditions. The advantages and disadvantages among all those techniques are also examined and discussed in detail.
Characterizing local anisotropy of coercive force in motor laminations with the moving magnet hysteresis comparator
Authors: Garshelis I. J. , Crevecoeur G.
Published: February 2014

Non oriented silicon steels are widely used within rotating electrical machines and are assumed to have no anisotropy. There exists a need to detect the anisotropic magnetic properties and to evaluate the local changes in magnetic material properties due to manufacturing cutting processes. In this paper, the so called moving magnet hyteresis comparator is applied to non destructively detect directional variations in coercive force in a variety of local regions of rotor and stator laminations of two materials commonly used to construct induction motors cores. Maximum to minimum coercive force ratios were assessed, varying from 1.4 to 1.7.
Hydrogen migration dynamics in hydrated Al clusters: The Al17(−)·H2O system as an example
Authors: Álvarez-Barcia S. , Flores J. R.
Published: February 2014

The Alm(−)·(H2O)n systems are known to undergo water splitting processes in the gas phase giving HkAlm(OH)k(−)·(H2O)n−k systems, which can generate H2. The migration of H atoms from one Al atom to another on the cluster's surface is of critical importance to the mechanism of the complete H2 production process. We have applied a combination of Molecular Dynamics and Rice-Ramsperger-Kassel-Marcus theory including tunneling effects to study the gas-phase evolution of HAl17(OH)(−), which can be considered a model system. First, we have performed an extensive search for local minima and the connecting saddle points using a density functional theory method. It is found that in the water-splitting process Al17(−)·(H2O) → HAl17(OH)(−), the H atom which bonds to the Al cluster losses rather quickly its excess energy, which is easily “absorbed” by the cluster because of its flexibility. This fact ultimately determines that long-range hydrogen migration is not a very fast process and that, probably, tunneling only plays a secondary role in the migration dynamics, at least for moderate energies. Reduction of the total energy results in the process being very much slowed down. The consequences on the possible mechanisms of H2 generation from the interaction of Al clusters and water molecules are discussed.
A 65-kV insulated gate bipolar transistor switch applied in damped AC voltages partial discharge detection system
Authors: Jiang J. , Ma G. M. , Luo D. P. , Li C. R. , Li Q. M. , Wang W.
Published: February 2014

Damped AC voltages detection system (DAC) is a productive way to detect the faults in power cables. To solve the problems of large volume, complicated structure and electromagnetic interference in existing switches, this paper developed a compact solid state switch based on electromagnetic trigger, which is suitable for DAC test system. Synchronous electromagnetic trigger of 32 Insulated Gate Bipolar Transistors (IGBTs) in series was realized by the topological structure of single line based on pulse width modulation control technology. In this way, external extension was easily achieved. Electromagnetic trigger and resistor-capacitor-diode snubber circuit were optimized to reduce the switch turn-on time and circular layout. Epoxy encapsulating was chosen to enhance the level of partial discharge initial voltage (PDIV). The combination of synchronous trigger and power supply is proposed to reduce the switch volume. Moreover, we have overcome the drawback of the electromagnetic interference and improved the detection sensitivity of DAC by using capacitor storage energy to maintain IGBT gate driving voltage. The experimental results demonstrated that the solid-state switch, with compact size, whose turn-on time was less than 400 ns and PDIV was more than 65 kV, was able to meet the actual demands of 35 kV DAC test system.
Development of three-wavelength CCD image pyrometer used for the temperature field measurements of continuous casting billets
Authors: Xie Zhi , Bai Haicheng
Published: February 2014

This paper develops an imaging based three-color pyrometer for the monitoring of temperature distribution in a continuous casting billet. A novel optical device, together with an embedded electronic system, is designed to sequentially collect a dark image and three thermal images with specified wavelengths on a same monochromatic charge-coupled-device (CCD). The three thermal images provide the basis for the determination of target temperature, while the dark image is used to online eliminate the dark noise of CCD with a differential method. This image pyrometer is not only independent of target emissivity but also overcomes the dissimilarity of measuring accuracy between the micro-sensors of CCD resulted from the non-uniformity of pixels’ intensity response and the vignetting of optical system. Furthermore, a precise two-color temperature field measuring model on the CCD pyrometer is established, based on which a self-adaptive light-integration mechanism is presented. Compared with the traditional fixed light-integration method, the measuring range of the pyrometer is greatly extended and its sensitivity in low temperature segment is improved. The test results in a steel factory demonstrate that the pyrometer is capable of meeting the requirement of surface temperature measurements about casting billets. Reliability and accuracy of measurement results are also discussed herein.
Local magnetoresistance through Si and its bias voltage dependence in ferromagnet/MgO/silicon-on-insulator lateral spin valves
Authors: Saito Y. , Tanamoto T. , Ishikawa M. , Sugiyama H. , Inokuchi T. , Hamaya K. , Tezuka N.
Published: February 2014

Local magnetoresistance (MR) through silicon (Si) and its bias voltage (Vbias) (bias current (Ibias)) dependence in ferromagnet (FM)/MgO/silicon-on-insulator lateral spin valves are investigated. From the experimental measurements, we find that the local-MR through Si increases with increasing Vbias. This anomalous increase of local-MR as a function of Vbias can be understood by considering the standard drift-diffusion theory improved by taking into account the difference in the interface resistances and first order quantum effect between FM/MgO/Si (source) and Si/MgO/FM (drain) interfaces. The interface resistance dependence on experimentally obtained local-MR ratios also agrees with the improved standard spin diffusion theory. These results indicate that experimentally observed local-MR is certainly related to the spin signal through the Si bulk band.
Microstructure investigations of hcp phase CoPt thin films with high coercivity
Authors: Yang Y. , Varghese B. , Tan H. K. , Wong S. K. , Piramanayagam S. N.
Published: February 2014

CoPt films have been grown in the past with a high anisotropy in L11 or L10 phase, and a high coercivity is observed only in L10 CoPt films. Recently, we have grown CoPt films which exhibited a high coercivity without exhibiting an ordered phase. In this study, high resolution transmission electron microscopy (HRTEM) investigations have been carried out to understand the strong thickness and deposition pressure dependent magnetic properties. HRTEM studies revealed the formation of an initial growth layer in a metastable hexagonal (hcp) CoPt with high anisotropy. This phase is believed to be aided by the heteroepitaxial growth on Ru as well as the formation of Ru-doped CoPt phase. As the films grew thicker, transformation from hcp phase to an energetically favourable face-centered cubic (fcc) phase was observed. Stacking faults were found predominantly at the hcp-fcc transformation region of the CoPt film. The higher coercivity of thinner CoPt film is attributed to relatively less fcc fraction, less stacking faults, and to the isolated grain structure of these films compared to the thicker films.
Application of cellular automata approach for cloud simulation and rendering
Authors: Christopher Immanuel W. , Paul Mary Deborrah S. , Samuel Selvaraj R.
Published: February 2014

Current techniques for creating clouds in games and other real time applications produce static, homogenous clouds. These clouds, while viable for real time applications, do not exhibit an organic feel that clouds in nature exhibit. These clouds, when viewed over a time period, were able to deform their initial shape and move in a more organic and dynamic way. With cloud shape technology we should be able in the future to extend to create even more cloud shapes in real time with more forces. Clouds are an essential part of any computer model of a landscape or an animation of an outdoor scene. A realistic animation of clouds is also important for creating scenes for flight simulators, movies, games, and other. Our goal was to create a realistic animation of clouds.
Quantitative comparison of dynamic flux distribution of magnetic couplers for roadway electric vehicle wireless charging system
Authors: Qiu Chun , Chau K. T. , Liu Chunhua , Li Wenlong , Lin Fei
Published: February 2014

This paper gives a quantitative comparison of magnetic couplers for electric vehicle (EV) wireless charging applications. Circular pad with ferrite spokes and coreless rectangular coils are specially selected for analysis. The dynamic flux density between couplers under high misalignment is studied by calculating the uncompensated power of the pick-up coupler. By using finite element analysis, the performance of each type of coupler is evaluated, and its adaptation to on-road EV charging are compared according to the flux distribution and effective charging area.
Microwave electromagnetic and absorption properties of magnetite hollow nanostructures
Authors: Yong Yang , Yang Yang , Wen Xiao , Jun Ding
Published: February 2014

Two types of magnetite (Fe3O4) hollow nanostructures, namely, nanoring (NR) and nanotube (NT), were fabricated by chemical method. The NR and NT exhibit a vortex and ferromagnetic domain structure, respectively, as revealed by 3D micromagnetic simulation. The measurement on microwave electromagnetic properties suggests that the NT exhibits obviously higher permittivity than that of the NR. In comparison, their initial permeability is close to each other. In addition, a broad nature resonance peak of the NR and NT is observed at 3.5 and 4.5 GHz, respectively. The calculated microwave absorption property indicates that the NT composite exhibits a broad band effective absorption (<−10 dB), which is superior to the NR. It suggests that the NT could serve as a promising candidate for microwave absorption.
Heavily strained BaZr0.8Y0.2O3−x interfaces with enhanced transport properties
Authors: Foglietti Vittorio , Yang Nan , Tebano Antonello , Aruta Carmela , Di Bartolomeo Elisabetta , Licoccia Silvia , Cantoni Claudia , Balestrino Giuseppe
Published: February 2014

A study of the structure and transport properties of highly textured, epitaxial oriented BaZr0.8Y0.2O3−x thin films grown on NdGaO3(110) is reported. Films have been grown by pulsed laser deposition and their conductivity studied as a function of temperature and thickness. The results show an increased conductance as the sample thickness decreases. The measured conductivity corresponding to an in-plane conductivity of 20 S cm−1 has been systematically observed in the range of 550–600 °C for several 10 nm-thick films. The high values of conductivity are possibly related to the high densities of defects, mostly dislocations at the interface of the film with the substrate.
An antidot array as an edge for total non-reflection of spin waves in yttrium iron garnet films
Authors: Gieniusz R. , Bessonov V. D. , Guzowska U. , Stognii A. I. , Maziewski A.
Published: February 2014

An array of antidots has been used as an edge to create the phenomenon of total non-reflection of spin waves in yttrium iron garnet films. At the critical angle between the line of antidots and the magnetic field, we observe a high-intensity beam of spin waves moving along the line of antidots. The properties of these waves are investigated experimentally by Brillouin light scattering spectroscopy. The conditions required for the occurrence of this phenomenon based on an analysis of the properties of the isofrequency dependencies are presented. The numerical simulations are in good agreement with those of the experimental measurements.
Optical properties of ultra-thin silicon films deposited on nanostructured anodic alumina surfaces
Authors: Wang Shu-Yi , Borca-Tasciuc Diana-Andra , Kaminski Deborah A.
Published: February 2014

Light trapping is crucial for thin film silicon solar cells and is often achieved by expensive, clean-room intensive nano-patterning methods. In this work, nanostructured silicon thin films were realized by direct deposition on substrates with nanoscale features prepared by simple and scalable fabrication based on electrochemical methods and wet etching. A broadband and angle-insensitive absorption enhancement of thin film silicon was observed. The photocurrent density shows improvements up to ∼40% in the AM 1.5 spectrum when comparing to the same thin film silicon deposited on smooth substrates. This approach not only demonstrates the advantage of simple fabrication but also has potential for ultra thin film photovoltaic applications.
Transfer efficiency analysis of magnetic resonance wireless power transfer with intermediate resonant coil
Authors: Huang S. D. , Li Z. Q. , Li Y.
Published: February 2014

Generally, for the magnetic resonance coupling wireless power transfer (WPT) system, the transfer efficiency and the transmission distance are contradictory. In order to simultaneously achieve the high transfer efficiency and the far transmission distance, some researchers have successfully proposed to use intermediate coils system to improve efficiency of WPT. In this paper, the expression for the efficiency of intermediate WPT system is obtained by applying coupled-mode theory. System efficiency is improved by optimizing key parameters of system. The intermediate WPT system via magnetic resonance coupling is designed. Simulation and experimental results validate the proposed optimization method.
Magnetic and structural properties of MnBi multilayered thin films
Authors: Hozumi T. , LeClair P. , Mankey G. , Mewes C. , Sepehri-Amin H. , Hono K. , Suzuki T.
Published: February 2014

Magnetic and structural properties of MnBi films with thicknesses up to 50 nm were investigated. Thin films of the MnBi LTP (Low Temperature Phase) were fabricated onto silica-glass substrates by sputter-deposition of Bi/Mn multilayer, followed by a subsequent annealing at about 550 °C for 30 min. Coercivity of such thin films is higher than 15 kOe, even though the film thickness is about 10 nm. These thin films show the preferential growth of c-axis of the LTP along the film normal. Moreover, high resolution transmission electron microscopy indicates that the LTP regions of 30–50 nm in size are physically isolated by Bi. The magnetization reversal mechanism of such a LTP region is mainly governed by a coherent rotation mode based on the δM curve measurement.
Micrometer-size Nd-Fe-B dots as model systems for the study of intergranular phase engineering in Nd-Fe-B permanent magnets
Authors: Le Roy Damien , Akdogan Ozan , Ciuta Georgeta , Dempsey Nora , Givord Dominique
Published: February 2014

Nd-Fe-B micrometer-size dots were prepared by optical lithography and sputtering. It is proposed to use such structures as model systems to study intergranular phase engineering in Nd-Fe-B permanent magnets. The influence of Ta, Nd, Dy, and Gd coatings on the magnetization reversal of such Nd-Fe-B dot arrays are compared, after different heat treatments. A very thin layer of Dy (tNdFeB/tDy = 120) was found to lead to a significant increase of the coercive field, up to 80% for a total equivalent Dy content of less than 5 at. % of all the Nd. A coercivity increase of up to 20% was found with Gd coating which is attributed to the so-called superferrimagnetic coupling phenomenon. Nd and Ta coating are neutral or detrimental to the magnetic hardness.
Comparison of rotary fertilizer dryer efficiency using electrical generator waste heat and liquefied petroleum gas as a heat source
Authors: Somsiritrakul S. , Suntivarakorn R. , Namwong K. , Treedet W.
Published: February 2014

This research compared rotary dryer efficiency using waste heat from an electrical generator and liquefied petroleum gas (LPG) as a heat source. A fertilizer drying experiment was conducted using residues from bio-gas production with a 3-ton/day capacity fertilizer dryer. Flow drying and drying efficiency was tested concurrently and measured together with water evaporation, energy consumption, and an economic analysis of data was conducted. Two heat sources were applied at the rates of 10, 15, and 20 rpm, drying cylinder with inclination angles of 1°, 3°, and 5°, and hot gas flow rates of 60, 120, and 180 m3/h. The tests showed that dryer inclination of 1°, heat flow rate of 180 m3/h, and dryer rotation speed at 10 rpm were the most optimal drying conditions. When waste heat from the electrical generator was applied, thermal efficiency was 79.19%, while the fertilizer's moisture content could be reduced from 57.84% dry weight standard to 12.45%, with an evaporation rate of 56.93 kg/h. The energy consumption was 23.78 kW h/1 ton of fertilizer. LPG drying yielded a heat efficiency of 72.69%, while moisture content went from 56.16% to 12.77%. Water evaporation from the fertilizer was 54.24 kg/h, and heat consumption was 986.33 kW h per 1 ton of fertilizer. Analysis revealed that fertilizer drying by waste heat from an electrical generator yields better efficiency and saves more energy than using LPG as the heat source. The cost of drying is also approximately 3.14 times lower.
First principle study of elastic and thermodynamic properties of ZrZn2 and HfZn2 under high pressure
Authors: Sun Na , Zhang Xinyu , Qin Jiaqian , Ning Jinliang , Zhang Suhong , Liang Shunxing , Ma Mingzhen , Liu Riping
Published: February 2014

A comprehensive investigation of the structural, elastic, and thermodynamic properties for Laves-phases ZrZn2 and HfZn2 are conducted using density functional total energy calculations combined with the quasi-harmonic Debye model. The optimized lattice parameters of ZrZn2 and HfZn2 compare well with available experimental values. We estimated the mechanical behaviors of both compounds under compression, including mechanical stability, Young's modulus, Poisson's ratio, ductility, and anisotropy. Additionally, the thermodynamic properties as a function of pressure and temperature are analyzed and found to be in good agreement with the corresponding experimental data.
Prep1 and Meis1 competition for Pbx1 binding regulates protein stability and tumorigenesis
Authors: Dardaei Leila , Longobardi Elena , Blasi Francesco
Published: February 2014

Significance

Tumor suppressor Pbx-regulating protein-1 (
Prep1
) and myeloid ecotropic viral integration site-1 (
Meis1
) oncogene are transcriptional regulators, which bind to the same partner, pre–B-cell leukemia homeobox-1 (
Pbx1
).
Meis1
overexpression induces tumorigenesis in
Prep1

i/i

mouse embryonic fibroblasts, which is counteracted by
Prep1
reexpression. The mechanism is unique: by binding to Pbx1, Prep1 regulates the stability of Meis1 and Pbx1. Influencing Meis1 stability, Prep1 controls the transcriptional landscape of Meis1 and hence, its tumorigenic activity. We also identify two novel Meis1 binding proteins, Ddx3x and Ddx5 RNA helicases, that are essential for cell proliferation and tumorigenesis, and their interaction with Meis1 is impaired at low Meis1 level. Thus, the level and function of three proteins (Prep1, Meis1, and Pbx1) of the same family are regulated by their stability, which depends on their interaction.
Continuity and quantity
Authors: Wårvik Brita
Published: February 2014

Givón’s (1995) quantity principle about the diagrammatic iconicity of coding forms has mostly been investigated for topic continuity and nominal elements. The present paper considers its applicability both to participant continuity and the continuity of time, focussing on their interaction in the organisation of narrative discourse. As an additional test of the hypothesis, the paper studies historical data, examining the structuring roles of signals of participant and temporal continuities in Old English narrative prose. The findings indicate that the choice of signals of the continuities of time and participants follows the iconic quantity principle of longer and informationally-heavier forms encoding greater degrees of discontinuity. The paper also underlines the importance of text type and genre-specific factors in investigations of discourse-structural signals. Specifically for the Old English narrative data, the study provides further support for the discourse marker role ofþa‘then’ as distinct from other temporal expressions.
Frequency distribution and spreading behavior of different types of mouth actions in three sign languages
Authors: Crasborn Onno A. , van der Kooij Els , Waters Dafydd , Woll Bencie , Mesch Johanna
Published: February 2014

In this paper, we present a comparative study of mouth actions in three European sign languages: British Sign Language (BSL), Nederlandse Gebarentaal (Sign Language of the Netherlands, NGT), and Swedish Sign Language (SSL). We propose a typology for, and report the frequency distribution of, the different types of mouth actions observed. In accordance with previous studies, we find the three languages remarkably similar — both in the types of mouth actions they use, and in how these mouth actions are distributed. We then describe how mouth actions can extend over more than one manual sign. This spreading of mouth actions is the primary focus of this paper. Based on an analysis of comparable narrative material in the three languages, we demonstrate that the direction as well as the source and goal of spreading may be language-specific.
Epenthesis in Italian Sign Language
Authors: Geraci Carlo
Published: February 2014

The aim of this study is to provide a detailed account for the phenomenon of movement epenthesis in Italian Sign Language (LIS). LIS displays at least two cases of epenthesis of movement, one affecting signs that involve contact with the body, the other affecting signs that do not (i.e. signs articulated in neutral space). The two cases of epenthesis of movement receive a unified analysis, once the mechanism of selection of the plane of articulation is spelled out. The general phenomenon of movement epenthesis is captured by a formal approach within a constraint-based framework, such as the one developed first for American Sign Language (ASL) in Brentari (1998). Cases of movement epenthesis in ASL will be discussed and compared to cases of LIS epenthesis
The use of space with indicating verbs in Auslan
Authors: de Beuzeville Louise , Johnston Trevor , Schembri Adam C.
Published: February 2014

One of the most salient and interesting aspects of the grammar of signed languages is their use of space to track referents through discourse. One way in which this has been observed is the spatial modification of lexical verbs to show semantic roles associated with the verb’s arguments. In this paper, a corpus of 50 narratives signed by native and near-native signers was annotated, coded, and analyzed to observe how often these verbs were modified spatially. The data indicate that the spatial modification of verbs in Auslan is far from obligatory, even for the marking of object/undergoer arguments. This may be evidence to support the hypothesis that spatial markings of this type are still in the process of grammaticalization.
Sign language text transcription and analyses using ‘Microsoft Excel’
Authors: Boyes-Braem Penny
Published: February 2014

This is a short explanation of how we have used the commercial software program ‘Microsoft Excel’ for transcriptions of Swiss German Sign Language monologues and conversations. Although the transcription is not directly linked to video, it has the advantage that various kinds of searches and correlations can be carried out on it, that the same basic transcript can be expanded or reduced to be used for different kinds of analyses, and that the analyses can be easily represented and printed out in different forms (charts, graphs, etc.).