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This work presents a study of the propagation characteristics in anisotropic solid and hollow homogeneous cylinders of infinite length using a polynomial method. The boundary conditions are automatically included into constitutive equations and subsequently into wave equations using the rectangular window function. The dispersion curves and displacement distributions are calculated for two anisotropic cases, cubic and hexagonal. To highlight the method's capabilities, the mathematical model is verified using numerical results obtained from solid and hollow anisotropic cylinders when normalized frequencies are compared to the results available in the literature in order to validate our method and the associated program. The suggested approach has a short convergence time and can accurately find all-acoustic eigenmodes regardless of their type. High accuracy is found between our results and the results reported in the literature. [ABSTRACT FROM AUTHOR]

We propose a polarizing interferometer based on a crystal anisotropic medium with variable thickness. The results of experimental simulation modelling show that this interferometer can be used to measure the coherence time in a wide time range from a few femtoseconds to tens of picoseconds. This can be used, for example, to control the picosecond pedestal of spectrally limited femtosecond pulses. [ABSTRACT FROM AUTHOR]

We develop the calculation of free energy in a nematic phase for a model of spherical particles with the long-range anisotropic interaction. We use the generalized van der Waals theory [A.Oukouiss and M. Baus, 1997. Phys.Rev.E55, 7242], suitably extended to the solid phase and to anisotropic interactions, to study the phase behaviour of a system of particles interacting via the isotropic Yukawa and nematic Mayer- Saupe interactions. In the first step we have studied the phase diagram for isotropic fluid of particles interacting via the Yukawa potential. We have found that the phase diagram depend on the range 1/k of the Yukawa attraction. In the second step we have studied the phase diagram of nematic fluid. We have found that the topology of the phase diagram depends sensitively on the relative strengths of the isotropic and nematic interactions. The nematic liquid phase is found to be thermodynamically stable with respect to isotropic phase in a large domain of the temperature-density plane contained between two triple lines. The results compare favourably with data obtained from other sources. [ABSTRACT FROM AUTHOR]

In this work, the study of the regularities of shear deformation in the bulk of fcc single crystals was carried out on the basis of molecular dynamics modeling. The deformation (010) of single crystals in the form of a tetragonal prism with lateral faces {101} and {100} with different ratios of the sample width to its height has been studied. Modeling has shown that the sample vertices are the preferred sites for shear initiation. It was found that the formation of deformation domains and the interaction of shear planes are due to the geometry of shear planes in the bulk of the single crystal: their location relative to the base stress concentrators and their orientation relative to the lateral faces. [ABSTRACT FROM AUTHOR]

The explosive TATB (1,3,5-triamino-2,4,6-trinitirobenzene) is formulated with various polymeric binders to create plastic-bonded explosives like PBX 9502 (95 wt% TATB and 5 wt% Kel-F binder). TATB crystals are graphitic and plate-like in nature and single crystals exhibit anisotropic thermal expansion where the direction normal to the platelet surface grows 10-20 times more than the in-plane platelet direction. Compactions of TATB, with and without binder, exhibit irreversible volume expansion, also known as ratchet growth, when thermal cycled to hot or cold temperatures. Specifically, when TATB-based compactions return to ambient after a temperature excursion away from room temperature, the volume of the specimen is slightly larger. Repeated thermal cycles can reduce the density by 1 to 2%. Axial confinement on a cylindrical specimen has previously been shown by us to suppress growth in the confining direction but then increase growth in the unconfined directions (likely due to creep effects). In the work presented here, PBX 9502 specimens were placed in cup assemblies where they were embedded in Sylgard (an incompressible silicon resin) to provide hydrostatic confinement when the assemblies were placed under different axial loads. The loaded cup assemblies were thermally cycled 10 times to hot and cold temperatures. Results show that increasing the hydrostatic confining pressure causes a decrease in the PBX 9502 volume expansion that occurs. [ABSTRACT FROM AUTHOR]

The role of texture in the dynamic yielding behaviour of magnesium alloy AZ31B has been studied in a series of instrumented plate-impact experiments. Specimens with thicknesses between 0.45 and 2 mm were cut parallel and perpendicular to the material extrusion direction and shock loaded to impact stresses around 3 GPa. Frequency-shifted photon doppler velocimetry was performed to capture breakout of the weak shockwave at the rear free-surface. Significant decay of the elastic precursor wave is observed over the examined thickness range. It is shown that shock compression along the extrusion direction (longitudinal loading) exhibits a markedly higher Hugoniot elastic limit (HEL) when compared to the perpendicular direction (transverse loading). Microstructural analysis via Electron Backscatter Diffraction (EBSD) demonstrates a strong basal texture in the material, with the c-axes of the HCP lattice aligned perpendicular to the extrusion direction. It is indicated that the peak elastic stress can be linked to the distribution of angles between the loading direction and the c- and a-axes of the grains, and by extension to the Schmid factors in the three primary slip systems. The present results demonstrate the importance of texture in the time-dependent inelastic deformation of common alloys with highly anisotropic crystal structures such as Mg AZ31B. [ABSTRACT FROM AUTHOR]

Crystals are anisotropic in nature and LAF crystals are of second order NLO with orthorhombic in character and have good NLO coefficient. The LAF crystal is grown-up by solution growth scheme and is subjected to Single crystal XRD study, Hardness measurements, Anti-diabetic study and Photoconductivity study and reported to measure for the LAF crystals. [ABSTRACT FROM AUTHOR]

Crystals are anisotropic in nature and LAF crystals are of second order NLO with orthorhombic in nature and have good NLO coefficient. The LAF crystal is grown and which is subjected to 1.SXRD study 2. Influx measurements 3. AC conductivity study 4.DC conductivity study and reported to measure the Influx behaviour and activation energy of LAF crystals. [ABSTRACT FROM AUTHOR]

Crystals are of anisotropic in nature and have the mixture of applications based on this property and based on Non Linear Optical - NLO chattels and directional output in electric, mechanic and optic axes. Second order semi organic type of second categorized Non Linear Optical (NLO) crystal as Lithium Para Nitrophenolate Trihydrate (LPNPTH) which is well developed by sluggish desertion solution growth routine which is computationally analyzed by DFT for Molecular Electrostatic Potential (MEP), Homo-Lumo, molecular harboring and Harboring applications by software tools of Gaussian 09 and Autodock, in the ground of molecular modeling, It is found that the band gap is 0.13928 eV and LPNPTH can be used for Alzheimer's disease by the approach of harboring. Affinity mappings for all the atom varieties at hand, over and above an electrostatic mapping, were work out with a framework spacing of 0.456 Å. The energy assessment between binding spots of MSF-aged Torpedo californica Acetylcholinesterase and LPNPTH are -5.54 kCal/mol. [ABSTRACT FROM AUTHOR]

Single crystal samples of NbAs2 semimetal have been synthesized and characterized by Raman spectroscopy. Magneto-transport experiments have been carried out in a temperature range of 2.5 K to 300 K under a magnetic field between 0 T and 14 T. The metallic temperature variation of resistivity without a magnetic field exhibits a huge magneto- resistance ∼105 % with 14 T at the lowest measured temperature. The non-linear Hall resistance evinces the role of multiple carriers in the transport and the positive Hall coefficient indicates a hole dominant system. Strongly temperature dependent carrier mobility below 75 K attains ultra-high values at low temperatures. Magnetization measurements display de Haas van Alphen oscillations that is anisotropic with respect to the crystal axes. Cyclotron mass and Dingle temperature have been estimated from the amplitude variation of oscillation in a varying field. The studies show that the low carrier mass and the resulting high mobility is the reason for the large magneto-resistance in NbAs2. [ABSTRACT FROM AUTHOR]

The calculation of elastic stresses generated by an acoustic wave in a plane layer is performed with the aid of the transfer matrix method. The elastic stress transfer matrix is found by the method of polynomials of principal minors. The components of the stress tensor of the crystal layer under conditions of six-beam diffraction of elastic waves are calculated. Conditions for the resonance of acoustic stresses are considered. [ABSTRACT FROM AUTHOR]

The paper presents the results of numerical simulation of the dynamic loading of a target from an anisotropic aluminum alloy AA7010-T6 with an isotropic aluminum projectile with different velocities. The process of destruction of an anisotropic target material was simulated by applying the fracture criterion from accumulated plastic deformations. This criterion makes it possible to take into account the anisotropy of the strength characteristics of the target material and to simulate the process of accumulation of microdamages. To study the effect of anisotropy of the mechanical characteristics of the material on its deformation, two types of calculations were carried out: in the first case, the mechanical properties of the target material along the loading direction were minimal, and in the second case, maximal. This statement of the problem corresponds to the statement of the problem in natural experiments in which the direction of the material rolling is oriented parallel or perpendicular to the direction of the load. [ABSTRACT FROM AUTHOR]

The paper presents the results of numerical simulation of the dynamic loading of an target from an anisotropic aluminum alloy 2024 by an isotropic aluminum projectile. The process of spalling destruction of an anisotropic target material was modeled with the help of two models of elastoplastic deformation of the material, in the first case the fracture criterion from accumulated plastic strains. In the second case, the elastoplastic material deformation model is supplemented by a fracture criterion containing the ultimate porosity. The obtained results of the calculations were compared with the experimental data for the case of the initial shock loading rate of 630 m/s. Numerical modeling of spall destruction of target is performed by the finite element method in a three-dimensional formulation. [ABSTRACT FROM AUTHOR]

The constitutive model development has been driven to a very accurate and fine-resolution description of the material behaviour responding to various environmental variable changes. The evolving features of the anisotropic behaviour during deformation, therefore, has drawn particular attention due to its possible impacts on the sheet metal forming industry. An evolving non-associated Hill48 (enHill48) model was recently proposed and applied to the forming limit prediction by coupling with the modified maximum force criterion. On the one hand, the study showed the significance to include the anisotropic evolution for accurate forming limit prediction. On the other hand, it also illustrated that the enHill48 model introduced an instability region that suddenly decreases the formability. Therefore, in this study, an alternative model that is based on the associated flow rule and provides similar anisotropic predictive capability is extended to chapter the evolving effects and further applied to the forming limit prediction. The final results are compared with experimental data as well as the results by enHill48 model. [ABSTRACT FROM AUTHOR]

The extrusion of magnesium alloys results in a pronounced fiber texture in which the basal planes are mostly oriented parallel and the c-axes are oriented perpendicular to the extrusion direction. Due to this texture the Strength Differential Effect (SDE), which describes the strength difference between tensile and compression yield strength, and the elastic anisotropy in the sheet plane are obtained during extrusion. The objective of the investigation was to decrease the SDE and anisotropy through specifically influencing the microstructure and texture. To accomplish this objective, the forming processes extrusion (EX) and equal channel angular pressing (ECAP) were combined and integrated into one extrusion die. This combination is called extrusion-shear (ES). With an ES-die, billets of the magnesium alloy AZ31B were formed into a sheet with the thickness of 4 mm and the width of 70 mm. The angles of the used ECAP-applications in the ES-dies were set to 90° and 135°. The results show that the extrusion-shear process is able to decrease the anisotropy and SDE through transformation of the texture compared to conventional extrusion process. Also grain refinement could be observed. However, the outcomes seem to be very sensitive to the process parameters. Only by using the ES-die with an angle of 135° the desired effect could be accomplished. [ABSTRACT FROM AUTHOR]

Finite Element (FE) forming simulation offers the possibility of a detailed analysis of thermoforming processes by means of constitutive modelling of intra- and inter-ply deformation mechanisms, which makes manufacturing defects predictable. Inter-ply slippage is a deformation mechanism, which influences the forming behaviour and which is usually assumed to be isotropic in FE forming simulation so far. Thus, the relative (fibre) orientation between the slipping plies is neglected for modelling of frictional behaviour. Characterization results, however, reveal a dependency of frictional behaviour on the relative orientation of the slipping plies. In this work, an anisotropic model for inter-ply slippage is presented, which is based on an FE forming simulation approach implemented within several user subroutines of the commercially available FE solver Abaqus. This approach accounts for the relative orientation between the slipping plies for modelling frictional behaviour. For this purpose, relative orientation of the slipping plies is consecutively evaluated, since it changes during forming due to inter-ply slipping and intra-ply shearing. The presented approach is parametrized based on characterization results with and without relative orientation for a thermoplastic UD-tape (PA6-CF) and applied to forming simulation of a generic geometry. Forming simulation results reveal an influence of the consideration of relative fibre orientation on the simulation results. This influence, however, is small for the considered geometry. [ABSTRACT FROM AUTHOR]

Anisotropic material deformation is modeled with the application of the finite element method. Hill's yield criterion is used for simplified conditions of the upsetting process. The largest flow stress direction is determined to be parallel to all the three coordinate axes by turns. It is discovered that the base of the cylinder can take an oval shape when the flow stress directions of various values lie in the base plane. In this case, the smaller axis of the oval corresponds to the largest flow stress direction. When the flow stress directions of various values lie in the longitudinal section plane of the workpiece, its shape remains cylindrical. The deformation load is higher in this case. [ABSTRACT FROM AUTHOR]

The microstructure banding of the 4340, 42CrMo4 and 20NC11 alloyed steels is estimated using the approach of the ASTM E 1268 standard. The values of the anisotropy index and microhardness are obtained on the longitudinal specimens at various distances from the center of round steel bars with various diameters. Impact strength values in the transversal and longitudinal directions of the bars are obtained. The correlation of the anisotropy index values and the mechanical properties (microhardness and impact strength) of the steels under consideration is derived. [ABSTRACT FROM AUTHOR]

Properties of fiber-reinforced composite are dominated by the microstructure of the fabricated part rather than the properties of constituent materials. As the microstructure of composite is related to the flow-processing route of the fiber-reinforced suspensions and the geometry of the mold, the microstructure of composite can be tailored in order to achieving high-performance composites by exercising control over the flow processing. Thus, numerical methods are used to model the resin flow, the fiber orientation, and mold design, and they become important challenges during molding process. In our previous research, a theoretical fiber-fiber interaction model with a global fiber interaction coefficient was developed. In this study, the three-dimensional (3D) fiber orientation distribution is predicted by combining our developed fiber interaction model and improved Anisotropic Rotary Diffusion - Retarding Principle Rate (iARD-RPR) model. The fiber orientation calculation started from the gate, and from a random orientation to alignment orientation is investigated at that location as the inlet boundary condition. Moreover, simplified deformation behavior of fountain flow was employed for fiber orientation in the flow front region. In experimental, short-glass fiber-reinforced polyamide 6 specimens produced using plate-shaped cavity having three different thicknesses ranging from 2 mm to 4 mm and with the fiber contents ranging from 30 wt% to 65 wt% are carried out using injection molding. 3D fiber orientation observation and measuring are exactly and automatically examined by Micro-computed tomography system. Comparisons with experimental results, it is showed that this advanced prediction methodology can be effectively used for the 3D fiber orientation prediction in high filler content composite parts. [ABSTRACT FROM AUTHOR]

The aim of this paper is to obtain the asymptotic multiscale method for finding solution of thermoelacticity problem for constructions made of 3D periodic anisotropic composites. This work is devoted to calculation of thermal stresses and the approach is based on cell functions method. Examples of solution are reported for several test cases and confirm the consistence of the cell functions method. [ABSTRACT FROM AUTHOR]

The paper investigates the influence of an external magnetic field on light propagation through a magnetooptical biaxial, biaxial hyperbolic and anisotropic magnetophotonic crystal. It is demonstrated that the application of a magnetic field results in splitting and reconnection of an isofrequency near the self-intersection point and thus it leads to the disappearance of conical refraction in a crystal. This effect makes it possible to control light propagation by means of a magnetic field. In addition, it is demonstrated that the diffraction divergence of a beam is suppressed in a homogeneous magneto-optical biaxial crystal. [ABSTRACT FROM AUTHOR]

We study the effect of cracking of a local anisotropic neutron star (NS) due to small density fluctuations. It is assumed that the neutron star core consists of leptons, nucleons and hyperons. The relativistic mean field model is used to describe the core of equation of state (EOS). For the crust, we use the EOS introduced by Miyatsu et al. [1]. Furthermore, two models are used to describe pressure anisotropic in neutron star matter. One is proposed by Doneva-Yazadjiev (DY) [2] and the other is proposed by Herrera-Barreto (HB) [3]. The anisotropic parameter of DY and HB models are adjusted in order the predicted maximum mass compatible to the mass of PSR J1614-2230 [4] and PSR J0348+0432 [5]. We have found that cracking can potentially present in the region close to the neutron star surface. The instability due cracking is quite sensitive to the NS mass and anisotropic parameter used. [ABSTRACT FROM AUTHOR]

Ultrasonic testing of jet engine titanium alloys is of high importance for the aircraft manufacturing industry. The quality of ultrasonic non-destructive testing is severely impacted by the titanium complex microstructure. These alloys have been extensively studied and single scattering models are now well known and implemented in ultrasonic propagation simulators. In addition, titanium billets and forged parts have been known to exhibit a highly anisotropic microstructure. We studied ultrasonic wave scattering in Til7 forged disk, through statistical analysis of the backscattered noise generated by the microstructure. More specifically, we focused on the quantification of multiple scattering relative to single scattering in the backscattered wave. To that end, we used the full matrix capture acquisition with a linear transducer array. Two phenomena were used to quantify the proportion of single scattering with respect to multiple scattering. The first is the coherent backscattering effect, used as a binary indicator of multiple scattering. The second is a repurposed version of the multiple scattering filter, recently developed on random rod forest and applied on Inconel alloys. With these methods, significant level of multiple scattering was consistently measured in Til7 forged disks, showing that ultrasonic testing could be enhanced by filtering the multiple scattering contribution. [ABSTRACT FROM AUTHOR]

The use of composite structures has importantly increased because of their reduced weight, assembly simplification and excellent specific strength and stiffness. The multiple possibilities of their manufacturing allow today to integrate within a single structure multiple functions: design, mechanical strength, multi-material...These structures, by their geometric and structural complexity (anisotropy, attenuation and scattering noise), do not always allow the application of conventional ultrasound real-time methods. In this communication, the problem related to anisotropy is treated in a first part with an analysis of the influence of materials properties on the conventional array imaging methods. In the second part, anisotropy is taken into account in the Total Focusing Method (TFM) to improve the image quality in carbon fiber composite plates. [ABSTRACT FROM AUTHOR]

The paper presents an integrated approach for determination of effective properties of anisotropic porous thermoelastic materials with a nanoscale stochastic porosity structure. This approach includes the effective moduli method for composite mechanics, the simulation of representative volumes and the finite element method. In order to take into account nanoscale sizes of pores, the Gurtin-Murdoch model of surface stresses and the highly conducting interface model are used at the borders between material and pores. The general methodology for determination of effective properties of porous composites is demonstrated for a two-phase composite with special conditions for stresses and heat flux discontinuities at the phase interfaces. The mathematical statements of boundary value problems and the resulting formulas to determine the complete set of effective constants of the two-phase composites with arbitrary anisotropy and with surface properties are described; the generalized statements are formulated and the finite element approximations are given. It is shown that the homogenization procedures for porous composites with surface effects can be considered as special cases of the corresponding procedures for the two-phase composites with interphase stresses and heat fluxes if the moduli of nanoinclusions are negligibly small. These approaches have been implemented in the finite element package ANSYS for a model of porous material with cubic crystal system for various values of surface moduli, porosity and number of pores. It has been noted that the magnitude of the area of the interphase boundaries has influence on the effective moduli of the porous materials with nanosized structure. [ABSTRACT FROM AUTHOR]

It has long been known that compacted composites containing TATB (triaminotrinitrobenzene) crystals undergo "ratchet growth," an irreversible volume expansion upon thermal cycling. A clear mechanism has not been established for this phenomenon, but is believed to arise from the highly-anisotropic CTE of TATB crystals and interactions caused by compaction. Explosive performance depends fundamentally on bulk density, so the effect may be important. PBX 9502 is a plastic bonded explosive containing 95 wt% TATB crystals. We have monitored uniaxial length changes of PBX 9502 specimens for various thermal cycles providing mechanistic insight. Post-cycled specimens were compression tested to determine if mechanical properties correlated with the detailed thermal history. [ABSTRACT FROM AUTHOR]

Three-dimensional flow of anisotropic plastic layer compressed by parallel rough flat dies is considered. Ideal plastic material model with Hill anisotropic yield criterion modification of Mises isotropic model is used with associated plastic flow rule. General solution of a thin layer plastic flow problem with Prandtl linear velocity and shear stress variation in layer thickness direction is presented. Effects of contact friction force vector module and direction on the layer pressure on the dies and the layer plastic flow are considered. [ABSTRACT FROM AUTHOR]

Scaling behavior of spin gap of a bond alternating spin-1/2 anisotropic Heisenberg chain has been studied both in ferromagnetic (FM) and antiferromagnetic (AFM) cases. Spin gap has been estimated by using exact diagonalization technique. All those quantities have been obtained for a region of anisotropic parameter Δ defined by 0 ≤ Δ ≤1. Spin gap is found to develop as soon as the non-uniformity in the alternating bond strength is introduced in the AFM regime which furthermore sustains in the FM regime as well. Scaling behavior of the spin gap has been studied by introducing scaling exponent. The variation of scaling exponents with Δ is fitted with a regular function. [ABSTRACT FROM AUTHOR]

Analytical wave models are inadequate to describe complex metallic microstructure interactions especially for near field anisotropic property effects and through geometric features smaller than the wavelength. In contrast, finite element ultrasound simulations inherently capture microstructure influences due to their reliance on material definitions rather than wave descriptions. To better understand and quantify heterogeneous crystal orientation effects to ultrasonic wave propagation, a finite element modeling case study has been performed with anisotropic titanium grain structures. A parameterized model has been developed utilizing anisotropic spheres within a bulk material. The resulting wave parameters are analyzed as functions of both wavelength and sphere to bulk crystal mismatch angle. [ABSTRACT FROM AUTHOR]

Ultrasonic field simulation is a key ingredient for the design of new testing methods as well as a crucial step for NDT inspection simulation. As presented in a previous paper [1], CEA-LIST has worked on the acceleration of these simulations focusing on simple geometries (planar interfaces, isotropic materials). In this context, significant accelerations were achieved on multicore processors and GPUs (Graphics Processing Units), bringing the execution time of realistic computations in the 0.1 s range. In this paper, we present recent works that aim at similar performances on a wider range of configurations. We adapted the physical model used by the CIVA platform to design and implement a new algorithm providing a fast ultrasonic field simulation that yields nearly interactive results for complex cases. The improvements over the CIVA pencil-tracing method include adaptive strategies for pencil subdivisions to achieve a good refinement of the sensor geometry while keeping a reasonable number of ray-tracing operations. Also, interpolation of the times of flight was used to avoid time consuming computations in the impulse response reconstruction stage. To achieve the best performance, our algorithm runs on multi-core superscalar CPUs and uses high performance specialized libraries such as Intel Embree for ray-tracing, Intel MKL for signal processing and Intel TBB for parallelization. We validated the simulation results by comparing them to the ones produced by CIVA on identical test configurations including mono-element and multiple-element transducers, homogeneous, meshed 3D CAD specimens, isotropic and anisotropic materials and wave paths that can involve several interactions with interfaces. We show performance results on complete simulations that achieve computation times in the 1s range. [ABSTRACT FROM AUTHOR]

Inertial-range asymptotic behavior of a vector (e.g., magnetic) field, passively advected by a strongly anisotropic turbulent flow, is studied by means of the field theoretic renormalization group and the operator product expansion. The advecting velocity field is Gaussian, not correlated in time, with the pair correlation function of the form ∝δ (t -t')/kd-1+ξ⊥, where k⊥ = ∣k⊥∣ and k⊥ is the component of the wave vector, perpendicular to the distinguished direction. The stochastic advection-diffusion equation for the transverse (divergence-free) vector field includes, as special cases, the kinematic dynamo model for magnetohydrodynamic turbulence and the linearized Navier-Stokes equation. In contrast to the well known isotropic Kraichnan's model, where various correlation functions exhibit anomalous scaling behavior with infinite sets of anomalous exponents, here the dependence on the integral turbulence scale L has a logarithmic behavior: instead of powerlike corrections to ordinary scaling, determined by naive (canonical) dimensions, the anomalies manifest themselves as polynomials of logarithms of L. [ABSTRACT FROM AUTHOR]

The FASTSUM collaboration has been carrying out simulations of Nf = 2+1 QCD at nonzero temperature in the fixed-scale approach using anisotropic lattices. Here we present the status of these studies, including recent results for electrical conductivity and charge diffusion, and heavy quarkonium (charm and beauty) physics. [ABSTRACT FROM AUTHOR]

Mechanical properties of a cable are of great importance in design and strength calculation of flexible cables. The problem of determination of elastic properties and rigidity characteristics of a cable modeled by anisotropic helical elastic rod is considered. These characteristics are calculated indirectly by means of the parameters received from statistical processing of experimental data. These parameters are considered as random quantities. With taking into account probable nature of these parameters the formulas for estimation of the macroscopic elastic moduli of a cable are obtained. The calculating expressions for macroscopic flexural rigidity, shear rigidity and torsion rigidity using the macroscopic elastic characteristics obtained before are presented. Statistical estimations of the rigidity characteristics of some cable grades are adduced. A comparison with those characteristics received on the basis of deterministic approach is given. [ABSTRACT FROM AUTHOR]

This paper studies the processes of fracture of barriers using the fracture criterion, allowing for consideration of large anisotropy for ultimate values of total plastic strains in various symmetry axes of an anisotropic material in conditions of sign-variable strain. All calculations were performed using the finite-element method under conditions of dynamic loading in three-dimensional graphics with the use of original software. It was shown that when modeling processes of fracture in barriers made of anisotropic and isotropic materials the differences in size and localization of fracture zones increase with the increase in the initial speed of shock loading of barriers. [ABSTRACT FROM AUTHOR]

Using the EBSD' SEM and TEM methods' the structure of surface layer of polycrystalline NiTi alloy samples was examined after the modification of material surface by the pulsed action of mean-energy silicon ion beam. It was found that the ion beam treatment would cause grain fragmentation of the near-surface layer to a depth 550 |¿m; a higher extent of fragmentation was observed in grains whose close-packed planes were oriented approximately in the same direction as the ion beam was. The effect of high-intensity ion beam treatment on the anisotropic behavior of polycrystalline NiTi alloy and the mechanisms involved were also examined. [ABSTRACT FROM AUTHOR]

Linear light polarizing films selectively transmit radiations vibrating along an electromagnetic radiation vector and selectively absorb radiations vibrating along a second electromagnetic radiation vector. It happens according to the anisotropy of the film . In the present study the polarization effects of methylene blue sensitized polyvinyl alcohol is investigated. The polarization effects on the dye concentration, heating and stretching of film also are evaluated. [ABSTRACT FROM AUTHOR]

The anisotropy of the critical current density Jc depends in general on both the properties of the flux lines (such as line tension, coherence length and penetration depth) and the properties of the defects (such as density, shape, orientation etc.). Whereas the Jc anisotropy in microstructurally clean films can be scaled to an effective magnetic field containing the Ginzburg-Landau anisotropy term, it is in general not possible (or only in a limited field range) for samples containing extended defects. Here, the Jc anisotropy of a Co-doped BaFe2As2 sample with 45° [001] tilt grain boundaries (GBs), i.e. grain boundaries created by 45° in-plane rotated grains, as well as extended Fe particles is investigated. This microstructure leads to c-axis correlated pinning, both due to the GBs and the Fe particles and manifests in a c-axis peak in the Jc anisotropy at low magnetic fields and a deviation from the anisotropic Ginzburg-Landau scaling at higher fields. Strong pinning at ellipsoidal extended defects, i.e. the Fe particles, is discussed, and the full Jc anisotropy is fitted successfully with the vortex path model. The results are compared to a sample without GBs and Fe particles. 45° GBs seem to be good pinning centers rather than detrimental to current flow. [ABSTRACT FROM AUTHOR]

Anisotropic gold nanoparticles are particularly important owing to their exciting applications in plasmonics as well as nanophotonics and biosensing. Herein, we have synthesized gold nanoplates/nanotriangles with an average side-length varying from 80 to 150 nm via a single step room-temperature solution-phase chemical reduction method utilizing predominantly the PVP-bromine interaction. The concentration of bromine as well as the surrounding reaction medium/environment plays an important role in determining the yield of gold nanoplates/nanotriangles at a given PVP to metal ratio. In the presence of bromine ions, the distinctive binding of PVP with metal salt changes owing to its conformational variations, as illustrated successfully through FTIR, optical absorption and TEM, leading to the formation of anisotropic gold nanoplates/nanotriangles. [ABSTRACT FROM AUTHOR]

Development of a simple method for incorporating phospholipids onto the surfaces of anisotropic silver nanorods as a stepping-stone for creating responsive and multifunctional nanocomposites. 1, 2-distearoyl-sn-glycero-3- phosphatidylcholine (DSPC)-silver nanorod composites were prepared by immobilizing liposomes onto the surface of cetyltrimethylammonium bromide (CTAB) capped silver nanorods. Here we report the role of phospholipids to control the self assembly of silver nanorods into agglomerate architectures ranging from open "end-to-end" networks to densely packed "side-to-side" arrays. The tuning of electrostatic interactions within the phospholipid layers is governed to lipid silver nanorod assembly and also about the organization of phospholipid layers themselves around nanorod surfaces. The initial studies on passive lipid functionalized nanorods could serve as the groundwork for introducing active components into these systems to make more switchable or reconfigurable nanocomposite material. Changing the surface species on silver nanorods from CTAB to DSPC is reflected in ?- potential measurements. The surface morphology is studied using SEM and TEM. The optical studies are carried out using UV-Vis spectroscopy. [ABSTRACT FROM AUTHOR]

This paper deals with the estimation of heat sources from infrared thermographic measures on anisotropic CFRP (Carbon-Fibre Reinforced Composites). Such procedure combines the data processing of the thermal signal, especially as spatial and temporal derivation quantities involved in the heat equation are notably affected by the measurement noise, and the determination of thermo-physical properties of the material, especially to account for the anisotropic conductivity behavior of the material. A comparative analysis of different filtering techniques is done to define a filtering method able to decrease the noise while keeping the useful features of the signal. Then, we use a homogenization scheme based on single-inhomogeneity solutions of Eshelby to derive the transversely isotropic thermal conductivity tensor. [ABSTRACT FROM AUTHOR]

In0.1Ga0.9As/Al0.3Ga0.7As quantum rings were fabricated by droplet epitaxy technique using molecular beam epitaxy (MBE). 7.5 ML In0.1Ga0.9As droplets are deposited on Al0.3Ga0.7As epitaxial layer at 350°C and 250°C. After that, they were crystallized under As4 pressure of 8x10-6 torr at 250°C. The surface morphology of quantum rings is studied by atomic force microscopy. It is found that quantum rings are not symmetrical due to anisotropic behavior of In and Ga atom migration during crystallization process. The quantum ring density of the sample deposition at 350°C and 250°C are 1x109 cm-2 and 2.6x109 cm-2, respectively. Consequently, the asymmetric quantum rings with deposition at 350°C give two photoluminescence (PL) peaks at 1.27 and 1.38 eV at 20K. However, the PL peak of quantum rings with deposition at 350°C is merged with GaAs peak due to the poor size distribution. [ABSTRACT FROM AUTHOR]