scholarly journals Magneto-Electric Effect on Guided Waves in Functionally Graded Piezoelectric–Piezomagnetic Fan-Shaped Cylindrical Structures

Materials ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2174 ◽  
Author(s):  
Bo Zhang ◽  
Jiangong Yu ◽  
Lahoucine Elmaimouni ◽  
Xiaoming Zhang
Keyword(s):  
Cross Section ◽  
Functionally Graded ◽  
Heaviside Function ◽  
Polynomial Method ◽  
Geometrical Shape ◽  
Cylindrical Structures ◽  
Geometric Size ◽  
The Cross ◽  
Functionally Graded Piezoelectric ◽  
Electric Effect

Functionally graded piezoelectric–piezomagnetic (FGPP) material simultaneously consists of piezomagnetic and piezoelectric phases, which are able to convert energy among mechanical, electric, and magnetic fields. The magneto-electric effect on waves in FGPP fan-shaped cylindrical structures is studied by exploiting the double Legendre orthogonal polynomial method. By means of the Heaviside function, the initial conditions are brought into wave motion equations. Dispersion properties, electric and magnetic potential, and the Poynting vector are calculated. Subsequently, the effect of the graded variation and geometric size on wave characteristics is analyzed. The FGPP fan-shaped cylindrical structures are of complex geometrical shape and material inhomogeneity, so their influences on the magneto-electric effect are the focus of discussion. Results reveal that the cut-off frequencies have a negative relationship with the cross-section area of the structure. The magneto-electric effect could be adjusted via altering the geometric size of the cross-section. These results can be utilized to design and optimize piezoelectric–piezomagnetic fan-shaped transducers.

Production and Properties of Functionally Graded UHPFRC Beams

2015 ◽  
Vol 1106 ◽  
pp. 156-159
Author(s):  
Milan Rydval ◽  
Petr Huňka ◽  
Jiří Kolísko
Keyword(s):  
Czech Republic ◽  
Cross Section ◽  
Steel Fibre ◽  
Volume Fraction ◽  
Functionally Graded ◽  
The Czech Republic ◽  
Fibre Distribution ◽  
Steel Fibres ◽  
Layered Beams ◽  
The Cross

Ultra-High Performance Fibre Reinforced Concrete (UHPFRC) is a fine-gained composite material achieving both high compressive and tensile strengths. Values of compressive strength, tensile strength and bending strength depend not only on a composition of the mixture itself, but also on the border conditions of the setting of the test, it means the support type, the loading rate etc. UHPFRC is used not only in European countries (Germany, France, Holland), but in distant countries (USA, Japan, Australia), too. In the Czech Republic is UHPFRC produced mainly in laboratories. The first using of UHPFRC for the real construction in the Czech Republic was a production of lost shuttering slabs that were used at the reconstruction of the raod-bridge across R10 highway. These results of the lost shuttering slabs became the base of a more detailed research of the homogeneity of the steel fibre distribution and its impact on load bearing capacity of the UHPFRC elements. Experimental beams with a different volume fraction of steel fibres were made and tested on the basis of the determined results of a nonhomogeneous fibre distribution at the cross section of lost shuttering slabs. Then the layered beams with a controlled steel fibre distribution at the cross section were made and tested too. The test results together with a description and characterization of the behaviour of tested homogeneous beams with different volume fraction of the steel fibres and functionally layered beams are published in this paper.

scholarly journals General non-uniform quadrilateral cross-sections for thin-walled FG sandwich beams

2021 ◽  
Vol 15 (2) ◽  
pp. 90-100
Author(s):  
Tan-Tien Nguyen ◽  
Quoc-Hung Nguyen ◽  
Thang D. Le ◽  
Hiep D. Le
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Higher Order ◽  
Functionally Graded ◽  
Sandwich Beams ◽  
Finite Element Package ◽  
Fg Beam ◽  
Thin Walled ◽  
The Cross ◽  
Beam Frame

The paper aims at introducing an analysis of thin-walled functionally graded sandwich beams for general non-uniform quadrilateral cross-sections. Generally, the materials are assumed to be graded through the thickness following a predefined shape while Poisson's ratio kept as a constant due to its less domination. The cross-section linearly varies from one end to another end of the beam. In order to relax the difficulties in modeling as well as capturing the behaviors of thin-walled functionally graded beams, a higher-order approach has been applied including warping, coupling distortions as well as Poisson's distortion. A multi-separated beam on each edge of the cross-section which is an application of the so-called beam-frame-modal method is adopted. Subsequently, the effects of these major importance along with anisotropy of materials are then fully considered. As a consequence, the analysis is able to extensively applied to closed-section beam-shells with different curvatures. In order to illustrate the accuracy and computational efficiency of the method, various examples have been conducted in which the results obtained from finite element package as ABAQUS are employed. Keywords: quadrilateral cross-section; thin-walled FG beam; higher-order coupling; beam frame modal.

scholarly journals Decay rates of Saint-Venant type for a functionally graded heat-conducting hollowed cylinder

2018 ◽  
Vol 24 (5) ◽  
pp. 1368-1386 ◽  
Author(s):  
Mari Carme Leseduarte ◽  
Ramon Quintanilla
Keyword(s):  
Cross Section ◽  
Liouville Problem ◽  
Decay Rates ◽  
Functionally Graded ◽  
Spatial Inhomogeneity ◽  
Heat Conducting ◽  
End Effects ◽  
Material Inhomogeneity ◽  
Rate Of Decay ◽  
The Cross

In this paper we consider the case of a functionally graded heat-conducting hollowed cylinder. Our purpose is to investigate the consequences of the material inhomogeneity on the decay of Saint-Venant end effects in the case of linear isotropic rigid solids. The mathematical issues involve the implications of spatial inhomogeneity on the decay rates of solutions to Dirichlet boundary-value problems. The rate of decay is characterized in terms of the smallest eigenvalue of a Sturm–Liouville problem. We first consider the case where the inhomogeneity depends on the radius of the cross-section, but later we also consider the case where the inhomogeneity also depends on the axial variable. The last section considers the case where the cross-section is increasing. Some tables and figures illustrate our estimates.

Material tailoring in functionally graded rods under torsion

2014 ◽  
Vol 228 (18) ◽  
pp. 3283-3295 ◽  
Author(s):  
F Liaghat ◽  
MR Hematiyan ◽  
A Khosravifard
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Torsional Rigidity ◽  
Optimization Methods ◽  
Arbitrary Cross Section ◽  
Functionally Graded ◽  
Material Tailoring ◽  
Graded Material ◽  
The Cross ◽  
Torsional Analysis

Material tailoring in functionally graded isotropic hollow rods of arbitrary cross section under torsion is studied. The purposes of material tailoring pursued in this paper are divided into two categories. In the first category, we find the variation of the volume fractions of constituents of a functionally graded member under torsion to obtain an appropriate distribution of shear stress over the cross section. In the second category, the torsional rigidity of a rod with a pre-defined mass is maximized by appropriate determination of the variation of constituents of the functionally graded material. Hollow rods are studied in this paper since they have higher torsional rigidity compared to solid members with the same mass. Meshless numerical methods are used for torsional analysis of the cross sections. Moreover, numerical optimization methods are used for material tailoring of the rods. Several examples with different cross sections are presented to investigate the usefulness of the proposed technique on achieving the mentioned purposes.

The Effect of the Geometrical Shape and Size of the Cross Section on the Spin-Polarized Transport and the Giant Magnetoresistance : Finite Element Method Analysis

2007 ◽  
Vol 124-126 ◽  
pp. 843-846
Author(s):  
Eun Sun Noh ◽  
Sergio E. Ulloa ◽  
Hyuck Mo Lee
Keyword(s):  
Cross Section ◽  
Giant Magnetoresistance ◽  
Geometrical Shape ◽  
Transmission Coefficients ◽  
Spin Polarized ◽  
Polarized Transport ◽  
The Cross ◽  
Spin Polarized Transport ◽  
Shaped Cross Section ◽  
Shape And Size

We analyze the effect of the geometrical shape and size of the cross section on the spin-polarized transport and the giant magnetoresistance (GMR) by a finite element method, and evaluate the stability and the physical properties of nano-scale spin valves. We calculate the transmission coefficients in the ballistic regime by using a transfer-matrix method, and evaluate the GMR of the current perpendicular to the plane (CPP) by using a circuit theory. The conduction-band structure is simplified to the potential step, which is determined by combining the interfacial parameters calculated by first-principles with the free electron model. The geometrical shapes of the cross section are line and square. As a result, the cross sectional shape has a significant effect on the spin-polarized transport and the GMR. The square-shaped cross section has an advantage of the large GMR, which is contrary to the line-shaped cross section. These phenomena result from the difference of the cut-off energies with the transverse modes and, consequently, the different spin-down transmission coefficients.

A New Approach to the Demonstration of Oxidase-Localization Using Tannic Acid Or Catechin

1973 ◽  
Vol 31 ◽  
pp. 698-699
Author(s):  
V. Mizuhira ◽  
Y. Futaesaku
Keyword(s):  
Cross Section ◽  
Tannic Acid ◽  
Elastic Fiber ◽  
The Other ◽  
New Approach ◽  
Tissue Block ◽  
Active Reaction ◽  
The Cross

Previously we reported that tannic acid is a very effective fixative for proteins including polypeptides. Especially, in the cross section of microtubules, thirteen submits in A-tubule and eleven in B-tubule could be observed very clearly. An elastic fiber could be demonstrated very clearly, as an electron opaque, homogeneous fiber. However, tannic acid did not penetrate into the deep portion of the tissue-block. So we tried Catechin. This shows almost the same chemical natures as that of proteins, as tannic acid. Moreover, we thought that catechin should have two active-reaction sites, one is phenol,and the other is catechole. Catechole site should react with osmium, to make Os- black. Phenol-site should react with peroxidase existing perhydroxide.

Energy Distribution in Electron Beams

1972 ◽  
Vol 30 ◽  
pp. 568-569
Author(s):  
Tamotsu Ohno
Keyword(s):  
Electron Beam ◽  
Energy Distribution ◽  
Cross Section ◽  
Integral Curve ◽  
Electron Beams ◽  
Electron Gun ◽  
Angular Divergence ◽  
Apparent Increase ◽  
Integral Width ◽  
The Cross

The energy distribution in an electron; beam from an electron gun provided with a biased Wehnelt cylinder was measured by a retarding potential analyser. All the measurements were carried out with a beam of small angular divergence (<3xl0-4 rad) to eliminate the apparent increase of energy width as pointed out by Ichinokawa.The cross section of the beam from a gun with a tungsten hairpin cathode varies as shown in Fig.1a with the bias voltage Vg. The central part of the beam was analysed. An example of the integral curve as well as the energy spectrum is shown in Fig.2. The integral width of the spectrum ΔEi varies with Vg as shown in Fig.1b The width ΔEi is smaller than the Maxwellian width near the cut-off. As |Vg| is decreased, ΔEi increases beyond the Maxwellian width, reaches a maximum and then decreases. Note that the cross section of the beam enlarges with decreasing |Vg|.

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