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Abstract: This is a review of a large body of work undertaken during the past 3–4 decades, by the author, who has worked in both the physical and the biological sciences. We begin with two assumed principles that are taken to be fundamental to the process of perception. The first is termed the reflexive property, and the second the uncertainty property. The former implies that the perceived world always mirrors a property of the perceiving system. The latter means that perception, both in the physical and biological worlds, always implies making a choice from among alternatives. We integrate these principles to develop equations diagrammatically, essentially using a set of cartoons. The equations are not derived rigorously – that can be found in other publications – but rather take shape pictorially, to give the reader the gist of the idea. The result is a single equation that has a good deal of scope in predicting events within sensory science. This single equation, suitably constrained, can be used to derive many of the hitherto empirical equations found in sensory science. By rooting perception in the physical, rather than the biological realm, this equation tells us about sensory systems that may be present throughout our universe, since the universe operates everywhere using the same laws of physics. [Copyright &y& Elsevier]

Abstract: DuMux is a free and open-source simulator for flow and transport processes in porous media, based on the Distributed and Unified Numerics Environment (DUNE). Its main intention is to provide a sustainable and consistent framework for the implementation and application of model concepts, constitutive relations, discretizations, and solvers. The paper provides an overview of DuMux with the focus on software-related aspects. Selected examples highlight the multi-scale and the parallel capabilities. [Copyright &y& Elsevier]

Abstract: The analyzability of the universe into subsystems requires a concept of the “independence” of the subsystems, of which the relativistic quantum world supports many distinct notions which either coincide or are trivial in the classical setting. The multitude of such notions and the complex relations between them will only be adumbrated here. The emphasis of the discussion is placed upon the warrant for and the consequences of a particular notion of subsystem independence, which, it is proposed, should be viewed as primary and, it is argued, provides a reasonable framework within which to sensibly speak of relativistic quantum subsystems. [Copyright &y& Elsevier]

Abstract: In this paper we show the existence of families of triple or quadruple nested planar central configurations for the -body problem with . More precisely for we nested three 2-collinear central configurations, for we nested four 2-collinear central configurations and for we nested three equilateral triangular central configurations. As far as we know these are the first examples of planar triple and quadruple nested central configurations. [Copyright &y& Elsevier]

Abstract: Delamination is an important failure mechanism in certain types of composite structures. As layers of the composite become separated from one another, the composite loses some of its structural integrity and may not be capable of supporting the intended loads. Detecting this type of damage is currently a problem of interest to the structural health monitoring community. However, in order to design an appropriate detection strategy, knowledge of the underlying physics of delaminated structures is essential. Here, a low-dimensional model of a delamination in a laminated beam is developed. The model consists of only five elements yet is capable of capturing much of the behavior observed in an accompanying experiment. Both experimental and theoretical results are presented for the static response of a thin, delaminated beam. [Copyright &y& Elsevier]

Abstract: The tripartite nonlocality is measured by the extent of violation of multipartite Bell inequality in Tavis-Cummings model with cavity loss. The effect of Bell-nonlocality sudden death is demonstrated. It is important that the study of tripartite system can exhibit fundamental characteristics which do not exist in bipartite systems. [Copyright &y& Elsevier]

Abstract: At the turn of the nineteenth and twentieth centuries a concerted effort was made in the discipline of fluid mechanics to make hidden and fleeting processes visible and to capture the results photographically. I examine two important cases. One concerns the photographs taken by H. S. Hele-Shaw in the 1890s showing the flow of a “perfect”, frictionless fluid. The other case deals with the photographs of boundary layer separation taken by Ludwig Prandtl. These were presented to the Third International Congress of Mathematicians in Heidelberg in 1904. My concern in both cases will be with the relation of the photographs to the reality actually or putatively portrayed in the photograph. Superficially the two cases are very different. “Perfect” fluids were accepted as mere mathematical abstractions to which nothing real could correspond while the reality of the boundary layer has been accepted as a discovery of enormous physical and technical importance. A detailed examination, however, suggests some inner connections of a kind that challenges the understanding of certain “common sense” distinctions between the two cases. [Copyright &y& Elsevier]

Abstract: We introduce a game admitting both classical and quantal players. Strategies are determined by the initial conditions of the associated dynamical system, whose time evolution is characterized by the existence of attractors that represent the possible results of the game. The physics associated to the interaction between matter and a single-mode of an electromagnetic field within a cavity is cast in these game theory terms. [Copyright &y& Elsevier]

Abstract: This paper hands in a review of the basic issues about the statics of tensegrity structures. Definitions and notation for the most important concepts, borrowed from the vast existing literature, are summarized. All of these concepts and definitions provide a complete mathematical framework to analyze the rigidity and stability properties of tensegrity structures from three different, but related, points of view: motions, forces and energy approaches. Several rigidity and stability definitions are presented in this paper and hierarchically ordered, from the strongest condition of infinitesimal rigidity to the more wide concept of simple rigidity, so extending some previous classifications already available. Important theorems regarding the relationship between these definitions are also put together to complete the static overview of tensegrity structures. Examples of different tensegrity structures belonging to each of the rigidity and stability categories presented are described and analyzed. Concluding the static analysis of tensegrity structures, a review of existing form-finding methods is presented. [Copyright &y& Elsevier]

Abstract: Gamma irradiation of canola meal (at doses of 25, 50 and 75kGy) could alter its ruminal protein degradation characteristics by cross-linking of the polypeptide chains. This processing resulted in decrease (linear effect, P<0.001) of ruminal protein degradation and increase (linear effect, P<0.001) of intestinal protein digestibility. The results showed that gamma irradiation at doses higher than 25kGy can be used as a cross-linking agent to improve protein properties of supplements in ruminant nutrition. [Copyright &y& Elsevier]

Abstract: The paper introduces precise definitions of the inevitabilist and contingentist positions. On this basis, it reveals the analytical structure and some inherent difficulties of the contingentist/inevitabilist issue. It then discusses some of these difficulties, relying on the thought-experiment of a ‘divided physics’ (two successful physics that have developed in complete isolation from each other). Along the way, it investigates the kinds of differences that two alternative physics should present, if they are to give rise to non-benign forms of contingentism. [Copyright &y& Elsevier]

Abstract: We have reformulated the phase change approach to the theory of conical intersections suggested by Zilberg and Haas [S. Zilberg, Y. Haas, Adv. Chem. Phys. 124 (2002) 433]. We use the fact that the phase change loop variable ϕ in polar co-ordinates in the space of nuclear co-ordinates is related to the transformation of the diabatic VB states defined at the apex of the cone in a conical intersection. Thus one can use the basis transformation generated by θ to yield a sequence of orthogonal pairs of VB structures (anchors) at any value of ϕ in the loop in nuclear configuration space. In this way the branching plane concept becomes related to VB wavefunctions based on the correspondence between the two angles. The theory is developed in detail using a simple three orbital three electron example. Examples are presented for four and six orbitals. In the later case, our results differ from those of Zilberg and Haas. [Copyright &y& Elsevier]

Abstract: We analyze a class of dual pairs of heterotic and type I models based on freely-acting orbifolds in four dimensions. Using the adiabatic argument, it is possible to calculate non-perturbative contributions to the gauge coupling threshold corrections on the type I side by exploiting perturbative calculations on the heterotic side, without the drawbacks due to twisted moduli. The instanton effects can then be combined with closed-string fluxes to stabilize most of the moduli fields of the internal manifold, and also the dilaton, in a racetrack realization of the type I model. [Copyright &y& Elsevier]

Abstract: The behaviour of balanced laminates (symmetric, antisymmetric and asymmetric) under repeated low energy hits of a 12.1mm hemispheric impactor was evaluated. The resistance to the impulsive force was found to be influenced by the stacking sequence and the crack path through the laminate. The symmetric plate with different ply directions proved to have best resistance to impact. The rate of damage progression in the event was characterised by an equation from the energy profile that correlates the propagation energy and time. This was differentiated to give the rate of damage evolution. A comparison of the bending stiffness obtained from the force–displacement plot of the first impact, revealed that the symmetric composite had the highest stiffness. Noted at perforation were fibre breakage and matrix cracking. [Copyright &y& Elsevier]

Abstract: Recent numerical simulations of MHD turbulence, under very different driving conditions, and by several different investigators, all indicate a sensitivity of the rms fluctuations to the ratio of the microscopic viscosity to resistivity. This dimensionless quantity is known as the magnetic Prandtl number Pm. In general, standard astrophysical accretion disks are characterized by Pm≪1 throughout their radial extent, while low luminosity accretors (e.g. Sag A∗) have Pm≫1. Here, we show that standard α models of black hole accretion disks have a transition radius, measured in tens of Schwarzschild radii, at which the flow goes from Pm≪1 to Pm≫1. Moreover, this transition may well be dynamically unstable, leading to a sort of two-phase “Prandtl number medium” We advance the idea that this is the physical reason underlying the change in the accretion properties of the inner regions of Keplerian disks, leading to a truncation of the cool disk (Pm≪1) and the onset of hot, low density gas flow (Pm≫1). [Copyright &y& Elsevier]

Abstract: A series of flow-cell experiments was conducted to investigate aqueous dissolution and mass-removal behavior for systems wherein immiscible liquid was non-uniformly distributed in physically heterogeneous source zones. The study focused specifically on characterizing the relationship between mass flux reduction and mass removal for systems for which immiscible liquid is poorly accessible to flowing water. Two idealized scenarios were examined, one wherein immiscible liquid at residual saturation exists within a lower-permeability unit residing in a higher-permeability matrix, and one wherein immiscible liquid at higher saturation (a pool) exists within a higher-permeability unit adjacent to a lower-permeability unit. The results showed that significant reductions in mass flux occurred at relatively moderate mass-removal fractions for all systems. Conversely, minimal mass flux reduction occurred until a relatively large fraction of mass (>80%) was removed for the control experiment, which was designed to exhibit ideal mass removal. In general, mass flux reduction was observed to follow an approximately one-to-one relationship with mass removal. Two methods for estimating mass-flux-reduction/mass-removal behavior, one based on system-indicator parameters (ganglia-to-pool ratio) and the other a simple mass-removal function, were used to evaluate the measured data. The results of this study illustrate the impact of poorly accessible immiscible liquid on mass-removal and mass-flux processes, and the difficulties posed for estimating mass-flux-reduction/mass-removal behavior. [Copyright &y& Elsevier]

Abstract: The present experimental study aims at developing a method to control the circular cylinder near wake by radial deformation and understand the underlying physics. Using an infra-red camera, we examine the temperature distribution of the near wake center line of a sinusoidal law radially deforming circular cylinder. From these measurements, the near wake is characterized by the length of the recirculation zone, the vortex formation zone length, the temperature fluctuation maximum intensity and the vortex street shedding frequency. For several deformations frequencies, we study the radial deformation influence on the near wake characteristics. It is noted that the wake structure is strongly affected by the deformation frequency. Among other things, we note the recirculation zone length reduction and the vortex formation zone length reduction when the radial vibrations are close to the “Lock-in” fundamental range. It is also noted that the variations of the vortex shedding frequency depend on the deformation frequency. [Copyright &y& Elsevier]

Abstract: The most common nonlinear equation of motion for the damped pulsation of a spherical gas bubble in an infinite body of liquid is the Rayleigh–Plesset equation, expressed in terms of the dependency of the bubble radius on the conditions pertaining in the gas and liquid (the so-called ‘radius frame’). However over the past few decades several important analyses have been based on a heuristically derived small-amplitude expansion of the Rayleigh–Plesset equation which considers the bubble volume, instead of the radius, as the parameter of interest, and for which the dissipation term is not derived from first principles. So common is the use of this equation in some fields that the inherent differences between it and the ‘radius frame’ Rayleigh–Plesset equation are not emphasised, and it is important in comparing the results of the two equations to understand that they differ both in terms of damping, and in the extent to which they neglect higher order terms. This paper highlights these differences. Furthermore, it derives a ‘volume frame’ version of the Rayleigh–Plesset equation which contains exactly the same basic physics for dissipation, and retains terms to the same high order, as does the ‘radius frame’ Rayleigh–Plesset equation. Use of this equation will allow like-with-like comparisons between predictions in the two frames. [Copyright &y& Elsevier]

Abstract: One simple method was introduced to prepare core–shell nanostructured conductive Ppy composite. Core Ppy particles were first introduced in the flexible shell solutions and then different core–shell structures can be prepared by electrospinning method. The results showed that: this method is very powerful to form core–shell nanostructures with electroconductive Ppy. [Copyright &y& Elsevier]

Abstract: Landauer''s principle is fundamental for the physics of information. It establishes the least amount of energy that needs to be dissipated in order to erase a bit of information. Using the Beck–Cohen representation of statistical ensemble distributions, we explore an extension of Landauer''s principle to systems out of equilibrium. [Copyright &y& Elsevier]

Abstract: By analyzing an instructive example, for testing many concepts and approaches in quantum mechanics, of a one-dimensional quantum problem with moving infinite square-well, we define geometric phase of the physical system. We find that there exist three dynamical phases from the energy, the momentum and local change in spatial boundary condition respectively, which is different from the conventional computation of geometric phase. The results show that the geometric phase can fully describe the nonlocal character of quantum behavior. [Copyright &y& Elsevier]

Abstract: Correlation functions, constructed from directional projections of the relative velocities of fragments, are used to determine the shape of the breakup volume in coordinate space. For central collisions of 129Xe+ natSn at 50 MeV per nucleon incident energy, measured with the 4π multidetector INDRA at GSI, a prolate shape aligned along the beam direction with an axis ratio of is deduced. The sensitivity of the method is discussed in comparison with conventional fragment–fragment velocity correlations. [Copyright &y& Elsevier]

Abstract: Vatakis, A. and Spence, C. (in press) [Crossmodal binding: Evaluating the ‘unity assumption’ using audiovisual speech stimuli. Perception &Psychophysics] recently demonstrated that when two briefly presented speech signals (one auditory and the other visual) refer to the same audiovisual speech event, people find it harder to judge their temporal order than when they refer to different speech events. Vatakis and Spence argued that the ‘unity assumption’ facilitated crossmodal binding on the former (matching) trials by means of a process of temporal ventriloquism. In the present study, we investigated whether the ‘unity assumption’ would also affect the binding of non-speech stimuli (video clips of object action or musical notes). The auditory and visual stimuli were presented at a range of stimulus onset asynchronies (SOAs) using the method of constant stimuli. Participants made unspeeded temporal order judgments (TOJs) regarding which modality stream had been presented first. The auditory and visual musical and object action stimuli were either matched (e.g., the sight of a note being played on a piano together with the corresponding sound) or else mismatched (e.g., the sight of a note being played on a piano together with the sound of a guitar string being plucked). However, in contrast to the results of Vatakis and Spence’s recent speech study, no significant difference in the accuracy of temporal discrimination performance for the matched versus mismatched video clips was observed. Reasons for this discrepancy are discussed. [Copyright &y& Elsevier]

Abstract: The semi-empirical mass formula of Bethe and von Weizsäcker is extended to include a number of additional terms. All possible combinations of extra terms are fitted in turn to the measured nuclear masses and the results analysed in order to reveal correlations and mutual influences between the various terms. The surface symmetry term is shown to be of critical importance in determining the Wigner and symmetry coefficients, while the pairing and global shell correction terms are largely independent of the other terms in the formula. The curvature term has a strong effect on the values of the other fit parameters. The interplay between different terms is found to be important. Some of the coefficients turn out to be much more poorly determined than would be suggested by standard fit errors alone. [Copyright &y& Elsevier]

Abstract: A discussion is presented on some physics behind the unusually long ranged dispersion forces recently predicted between one-dimensional and nanolayered structures with a zero electronic energy gap, such as metallic nanotubes and graphitic structures. The various results for these systems, previously obtained via a variety of formalisms, are here re-derived systematically from a single approach. [Copyright &y& Elsevier]

Spheroidal microstructures suitable for thixoforming, can be formed by a variety of techniques. From optical microscopy and electron backscattered diffraction observations, the mechanism of formation of such microstructure in an Al–Si alloy conditioned by the so-called deformation–recrystallization technique is described as an internal partition of the deformed dendrites. During heating and partial remelting, low angle boundaries turn into high angle boundaries, whose penetration by the liquid is energetically favorable, thus leading to a dispersion of spheroidal Al-α particles. [Copyright &y& Elsevier]

Insufficient bonding between multi-wall carbon nanotubes (MWCNTs) and the matrix reduces the effectiveness of MWCNT reinforcements in sol–gel silica dielectric composites. This paper investigates the efficacy of various surfactants in improving the bonding through morphological and mechanical characterization of MWCNT-reinforced sol–gel silica dielectric films. It is found that use of some surfactants while dispersing MWCNTs improves the modulus and hardness. The improved mechanical properties possibly reduce the delamination problem of Cu/low-k films during flip-chip packaging and wirebonding. [Copyright &y& Elsevier]

Like other interfaces, equilibrium grain boundaries are smooth at low temperature and rough at high temperature; however, little attention has been paid to roughening except for faceting boundaries. Using molecular dynamics simulations of face-centered cubic Ni, we studied two closely related grain boundaries with different boundary planes. In spite of their similarity, their boundary roughening temperatures differ by several hundred degrees, and boundary mobility is much larger above the roughening temperature. This has important implications for microstructural development during metallurgical processes. [Copyright &y& Elsevier]

The present study shows that nanostructure–dendrite composites successfully synthesize in the Fe–Zr binary eutectic system, exhibiting a better combination of strength and plasticity than bulk metallic glass or nanograined materials. The composites composed of microscaled dendritic phases (Fe2Zr or α-Fe) and nanoscaled lamellar eutectic matrix (Fe2Zr+α-Fe) exhibit high compressive strength (1.8–2.6GPa) and plasticity (2.5–12%) under compression. In particular, the plasticity can be improved when coarsened ductile dendritic phases are reinforced in the fine-scaled lamellar eutectic matrix. [Copyright &y& Elsevier]

This paper presents a creep–fatigue-interacted lifetime prediction methodology based on continuum damage mechanics for the Ni-based superalloy under cyclic loading at high temperature. A unified life estimation model has been developed enabling stress–strain curves and cumulative damage to be predicted. Four types of low cycle fatigue tests were carried out at 650°C. The effects of the levels of strain range and strain hold time together with frequency characteristics of fatigue behavior on the lifetime were investigated. [Copyright &y& Elsevier]

Quantitative atomic structure and phase analysis in the titanium aluminide intermetallic system of composition Ti–45Al–7.5Nb–0.5C (at.%) was conducted in situ by use of high-energy X-ray diffraction from a synchrotron and evaluated using the Rietveld method, implementing a model for atomic order in the α-phase which describes the order to disorder transition α2 →α at the eutectoid temperature. The order parameter exhibits unexpected behavior and is entangled with the competition of different kinetic processes. [Copyright &y& Elsevier]

Inspection of pre-polished surfaces of Mg–3Al–1Zn hot-rolled plate following 5% uniaxial compression revealed a distinctive heterogeneous deformation pattern. The pattern differed depending on the face examined. The greater share of the strain was born by regions characterized by grains considerably finer than the average. These regions displayed a favourable alignment for basal slip and were probably formed by shear banding during previous rolling. It is clear that local orientation softening leads to inhomogeneous deformation despite local grain size-hardening and twin activation. [Copyright &y& Elsevier]

The reported experimentally determined bulk modulus for Cr2AlC is 28–40% lower than the value obtained by ab initio calculations. To identify the origin of this extensive difference between theory and experiment, the elastic modulus of thin Cr2AlC films was measured by nanoindentation and the temperature dependence thereof was studied by ab initio molecular dynamics. Our experimental and theoretical elastic modulus data are within the expected error margin and hence consistent with the published ab initio data. [Copyright &y& Elsevier]

A series of wide band gap semiconductors, CuAlS2+x , with a chalcopyrite structure were synthesized in bulk form by spark plasma sintering. p-type conductions for all samples were confirmed by positive Seebeck and Hall coefficients. For excess S introduced into the system, the carrier concentration was highly enhanced, reaching 6.9×1019 cm−3 for the 10% doped sample, which results in a high conductivity of 4.6Scm−1 without decreasing the bang gap. [Copyright &y& Elsevier]

TiB2 particles were observed at the grain boundaries of an Al casting, suggesting they were pushed during solidification; however, a small proportion were retained within the α-Al grains due to engulfment. Crystallographic analysis of the TiB2 with the surrounding α-Al showed that very few particles segregated to the grain boundaries showed any systematic relationship, while 70% of the engulfed particles display one of two orientation relationships, suggesting that the formation of a low-energy crystallographic relationship assists engulfment. [Copyright &y& Elsevier]

Atomistic simulations using an EAM potential are carried out to investigate the first stages of plasticity in aluminium slabs, in particular the effect of both temperature and step geometry on the nucleation of dislocations from surface steps. Temperature is shown to significantly reduce the elastic limit, and to activate the nucleation of dislocation half-loops. Twinning occurs by successive nucleations in adjacent glide planes. The presence of a kinked step is shown to have no influence on the nucleation mechanisms. [Copyright &y& Elsevier]

Combined addition of strontium and boron led to a much greater decrease in the eutectic grain sizes in near-eutectic Al–Si alloys than that caused by addition of strontium alone. As expected, an increased cooling rate during solidification refines the eutectic grains. The mechanism of this refinement in the presence of strontium and boron is related to the combined effect of increased undercooling of the eutectic reaction and the effective number density of eutectic nuclei. [Copyright &y& Elsevier]

Extruded 15vol.% SiCp/Al–Cu–Mg composite was friction-stir-welded (FSW) and subjected to subsequent post-weld T4-treatment. The formation of Cu2FeAl7 phase with Fe resulting from steel tool wear was identified at or near the SiC particle interfaces by using transmission electron microscopy, high-resolution electron microscopy and differential scanning calorimetry. Two types of Cu2FeAl7 phases were observed: a single crystal phase and a polycrystalline nanostructured phase. No elemental iron was detected. The formation mechanism of the Cu2FeAl7 phase is discussed. [Copyright &y& Elsevier]

Niobium was found to be beneficial for alumina scale formation in newly developed creep-resistant austenitic stainless steels. Additions of both Ti and V degraded alumina scale formation, whereas alloys with individual additions of Ti or V were able to form protective alumina scales. The ability to form external alumina scales was lost in the lower Al- and Nb-containing alloys between 800 and 900°C. Compositions with the potential to form alumina at 900°C were identified. [Copyright &y& Elsevier]

Abstract: We give a detailed analysis of the superconformal fixed points of four-dimensional supersymmetric gauge theory with two spinors and vectors by using a-maximization procedure. [Copyright &y& Elsevier]

Abstract: In a previous study the authors analysed the evolution of the ion velocity distribution across a stationary exactly perpendicular one-dimensional model shock profile from a statistical physics perspective. The appropriate solution of Liouville''s equation (which was shown to be different to the classical Hamiltonian solution) has the property that contours of equal phase space probability do not correspond to contours of equal energy and it is this feature that leads to the observed anisotropic heating. In the present study we extend this statistical physics analysis to oblique low Mach number shocks and quantify the weak dependence of the ion heating on the shock geometry. [Copyright &y& Elsevier]

Nanoparticles and defects have been investigated using transmission electron microscopy in fully reacted YBa2Cu3O7−δ (YBCO), prepared by the metal–organic deposition (MOD) process. Two types of particles, Y2O3 and CuY2O5, ranging from 10 to 100nm, have been observed in the YBCO matrix. The YBCO contains a large number of planar defects and a considerable number of (110) rotational twins. Details of the nanoparticles and defects in the MOD-processed YBCO films are presented in this paper. [Copyright &y& Elsevier]

Abstract: The effects of applied transverse field on transition and compensation temperatures of the ternary alloy consisting of spins , , and are investigated by the use of a mean-field theory. The structure and the spin values of the model correspond to the Prussian blue analog of the type . We find that two or even three compensation points may be induced by a transverse field for the system with appropriate values of the parameters in the model Hamiltonian. In particular, the influence of a transverse field on the compensation point in the ground state is examined. [Copyright &y& Elsevier]

Abstract: The Al/p-Si Schottky diodes (33 dots) with the native interfacial insulator layer (SiO2) were fabricated on the same quarter Si wafer. The Schottky barrier height (SBH), ideality factor (n), interface state densities (N ss) and series resistance (R s) of these diodes have been calculated from their experimental forward bias current–voltage (I–V), reverse bias capacitance–voltage (C–V) and conductance–voltage (G/ω–V) measurements. Even though they are identically performed on the same quarter Si wafer, the calculated values of SBH have ranged from 0.680 to 0.736eV, and ideality factor n from 1.62 to 2.87, and interface state densities N ss from 0.395×1013 to 1.2×1013 eV−1 cm−2 and series resistance R s from 623 to 4900Ω. It was found that the values of barrier height Φ B obtained from C–V characteristics is larger than that of the value from I–V characteristics. The energy distribution of surface state density profiles for the selected six samples Al/p-Si Schottky diodes was determined from forward bias I–V characteristics by taking the bias dependence of the effective barrier height into account at room temperature. The experimental values of SBHs distributions obtained from the I–V and C −2–V characteristics have been fitted by a Gaussian function, and their mean values of SBHs have been calculated to be 0.708 and 0.810eV, respectively. Experimental results show that the interface states at a native insulator layer between metal and semiconductor play an important role in the value of the SBH, ideality factor, series resistance and the other main electrical parameters of Schottky diodes. [Copyright &y& Elsevier]

Abstract: We conducted nanoindentation to explore the hardness and elastic properties of silica stishovite, synthesized at high pressure and quenched to ambient conditions. A total of 10 crystallographic orientations were examined on selected grains with a maximum load of 4 or 20mN. We observed discontinuity in the load–displacement curve (pop-in) for the and grains subjected to a maximum load of 20mN. The single-crystal hardness at high plastic deformation is quasi-isotropic with an average of , similar to the polycrystalline hardness reported earlier; the theoretical hardness determined from the experiments is about . These two hardnesses suggest that stishovite is one of the hardest oxides. The measured indentation moduli are close to the predictions at low load (minor plasticity) but are considerably lower at high load (high plasticity). Both indentation hardness and modulus decrease with increasing plasticity. Our results underscore the necessity of considering the degree of plastic deformation when interpreting hardness and elastic moduli from indentation experiments. [Copyright &y& Elsevier]

Abstract: In this paper we present a study of the energy gaps, dielectric constants and their composition dependence in zinc-blende Cd1− x Zn x Te over the entire composition range (x from 0 to 1) at room temperature using pseudopotential formalism under a modified virtual crystal approximation which takes into account the effect of compositional disorder. It is showed that the theoretical model must include disorder effects in order to get a meaningful agreement with experiment. The theoretical expression which describes the compositional dependence of the fundamental energy gap is in good agreement with that observed by Tobin et al. [J. Electron. Mater. 24 (1995) 697]. [Copyright &y& Elsevier]

Abstract: The two-dimensional electron gas (2DEG) transport properties of two-step growth undoped Al0.25Ga0.75N/GaN heterostructures with semi-insulating buffer, grown by MOCVD, were investigated in a temperature range of 20–350K. Using the quantitative mobility spectrum analysis (QMSA) method, it was shown that significant parallel conduction does not occur in worked structures. In-plain growth axis strains are calculated using the total polarization-induced charge density taken as the sheet carrier density measured from the Hall effect. It was found that the calculated strain values are in good agreement with those reported. Influences of the two-step growth parameters such as growth ramp time, the annealing temperature of the GaN nucleation layer on the mobility, and density of the 2DEG are also discussed. [Copyright &y& Elsevier]

Abstract: We have studied the crystalline electric field (CEF) effect of the Ho1− x Dy x Ni2B2C system using the anisotropy and the temperature dependence of magnetic susceptibilities with magnetic field H perpendicular or parallel to c-axis, and estimated the magnetic exchange interaction constant of rare-earth ions perpendicular to the c-axis. The crystalline electric field parameter , the first Steven parameter and the most dominant term in this system, are determined from the and anisotropic Weiss temperatures and then show a broad minimum around x≈0.3, where superconducting transition temperature, T C, and Néel temperature, T N, are similar. [Copyright &y& Elsevier]

Abstract: The expressions of the light intensity (Poynting vector) and the transmission coefficient related to counterposition phenomenon are deduced. The counterposition phenomenon in the uniaxial crystal makes no difference to ordinary refraction in terms of energy transport efficiency though it carries the light energy in a different way. [Copyright &y& Elsevier]