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In this paper, the stiffness of carbon nanotube bundle (CNTB) reinforced composite is predicted by means of the Mori-Tanaka method and Eshelby method. The curvature of one CNTB on uniaxial aligned ...

The hygro-thermo-mechanical behavior of a ultra-high strength steel (UHSS) gasket under radial mechanical loads is investigated. By adopting an appropriate displacement function, the displacement, ...

The incremental theory of intelligence has been identified as a strong predictor of students’ learning motivation. Recent research has suggested various moderators of its effect. The present study ...

Based on the von Karman equation and classical thin plate theory, thermomechanical behavior of a rectangular high-strength low alloy (HSLA)-stiffened plate under low-velocity impact is investigated. First, the relation of the contact radius and the instantaneous relative displacement is obtained using the modified nonlinear Hertzian contact law. Second, based on the assumption that the stiffener cross section does not deform in its plane, the nonlinear governing equations in the form of displacements are obtained using the Hamilton’s variational principle. Finally, the unknown variable functions are discretized in space and time domains by utilizing the finite difference method and Newmark method, and the whole problem is solved by the iterative method. Numerical results denote that the geometrical parameters, temperature, boundary conditions, the initial velocity of impactor and the form of the stiffeners have great influences on deformation and stresses of the HSLA-stiffened rectangular plate.

The sharp-snouted pitviper, Deinagkistrodon acutus, belongs to the monotypic genus Deinagkistrodon of the family Viperidae. It is one of the important species of snakes for its commercial and medicinal value. Complete mitochondrial genome sequence of the D. acutus was sequenced by next-generation sequencing technology. The total mitochondrial genome is 17,538 bp in length, containing 13 protein-coding genes, 22 tRNA genes, 2 ribosome RNA genes, and 2 control regions. Most of the genes of D. acutus are encoded on the H-strand, except for the ND6 subunit gene and eight tRNA genes which distribute on the L-strand. Phylogenetic reconstruction result indicated that our newly determined mitochondrial genome sequence could meet the demands. The complete mitochondrial genome sequence presented here will be useful to study the evolutionary relationships and genetic diversity of D. acutus.

The complete mitochondrial genome (mitogenome) sequence of Sphenomorphus indicus was sequenced and characterized by next-generation sequencing technology. The total length of mitogenome is 17,027 bp and contains 13 protein-coding genes, 22 tRNA genes, 2 ribosome RNA genes, and 2 non-coding regions (the control region and the putative L-strand replication origin). Most of the genes of S. indicus are encoded on the H-strand, except for the ND6 subunit gene and 8 tRNA genes which is distributed on the L-strand. Phylogenetic reconstruction suggested that S. indicus is the sister group of the S. incognitus within the genus Sphenomorphus. The complete mitochondrial genome sequence presented here will be useful to study the evolutionary relationships and genetic diversity of S. indicus.

The Papenfuss' Rock Agama Laudakia papenfussi is an endemic species in the Tibet Autonomous Region of China. The complete mitochondrial genome sequence of this species was determined by shotgun sequencing. The total length of mitogenome is 17,005 bp and its base composition was 37.3% for A, 23.9% for T, 12.5% for G, and 26.3% for C, which contains 13 protein-coding genes, 22 tRNA genes, 2 ribosome RNA genes, and 2 control regions. The phylogenetic tree of L. papenfussi and 15 other related species was reconstructed using maximum likelihood (ML) methods. The mitogenome sequence presented here will be useful to understand the phylogenetic relationships of Laudakia.

In this article, thermoviscoelastic dynamic behavior of a double-layered cylinder with a thermal barrier coating under radially symmetric mechanic and thermal loadings is investigated. The double-layered hollow cylinder is constructed of a viscoelastic layer and a homogenous layer, and the cylinder is subjected to thermal shocking. The material parameters of the cylinder are assumed to be temperature-dependent. The governing equation of the motion of the double-layered hollow cylinder under both dynamic mechanical and thermal loads is obtained based on the plane-stain theory, meanwhile, the transient heat transfer problems are solved by the finite difference method (FDM), Newmark method (NM), and iterative method. Numerical results show that mechanical load, boundary conditions, temperature field and whether considering the viscoelasticity of the inner layer each have a great influence on the dynamic behavior of the double-layered hollow cylinder.

Based on von Karman non-linear strain-displacement relationships and classical thin plate theory, a list of non-linear dynamic equilibrium equations for a thin narrow composite strip with transverse matrix cracking under thermal and mechanic loads are established and solved by the finite difference method, Newmark method, Newton-Cotes method and iterative method synthetically. Numerical examples show effect of the mechanical parameters, thermal environment, damage evolution and geometric parameters for thermoviscoelastic dynamic behavior of the thin narrow composite strip.

An analytic method for bending analysis of a cylindrical shell composed by a functionally graded material (FGM), placed in a uniform magnetic field, subjected to mechanical and thermal loads is presented. Based on the classical linear shell theory, the equations with the radial deflection and horizontal displacement are derived, and exact solution of the magnetothermoelastic bending problem is obtained. For the FGM cylindrical shell with fixed and simply supported boundary conditions, the effects of mechanical load, thermal load, magnetic intensity, volume exponent, and geometric parameters on the bending deformation of the FGM cylindrical shell are discussed.

Childhood obesity and overweight are among the most serious public health challenges in Taiwan. Moderate daily physical activity, limiting screen viewing, drinking more water, and consuming adequate fruits and vegetables are modifiable and particularly important for preventing childhood obesity. Self-efficacy, expectations, and self-control were used to predict each of the four behaviors. A valid and reliable instrument was administered to 222 upper elementary students. Minutes of physical activity were predicted by self-efficacy and self-control to exercise (R2 = 0.111). Hours of TV watching were predicted by self-efficacy of watching less than 2 hour of TV (R2 = 0.136). Glasses of water consumed were predicted by self-efficacy for drinking water and age (R2 = 0.093). Servings of fruits and vegetables consumed were predicted by self-efficacy of eating fruits and vegetables (R2 = 0.089). This research provided useful guidance based on social cognitive theory for building prevention programs specific to th...

In this article, analysis of vibrations and transient responses of a hollow cylinder made of functionally graded materials (FGMs) under a radially symmetric dynamic load is presented. The material of the FGM hollow cylinder is assumed to be isotropic with constant Poisson's ratio, exponentially-varying elastic modulus, and exponentially-varying density through the radial thickness. By means of the finite difference method and Newmark method, the governing equation of the FGM hollow cylinder under dynamic loads is solved. As numerical examples, the FGM hollow cylinder under impulsive load and that under sinusoidally varying dynamic load are discussed, and then many valuable characteristics are revealed.

Analytical study for electromagnetothermoelastic behavior of a solid cylinder composed of functionally graded piezoelectric material (FGPM), placed in a uniform magnetic field, subjected to electric, thermal, and mechanical loadings is presented. For the case that material properties obey an identical power law, exact solutions for stresses and perturbation of magnetic field vector in the FGPM solid cylinder are determined by using the theory of electromagnetothermoelasticity. Numerical examples and some useful discussions are presented to show the significant influence of material inhomogeneity; adopting a certain value of the inhomogeneity parameter and applying suitable loads can optimize the FGPM solid cylindrical structures.

Based on the thermoviscoelastic theory and the classic plate theory, thermoviscoelastic behavior of a circular plate made from high strength low alloy (HSLA) steel material is investigated. Applying the Kirchhoff hypothesis, the nonlinear motion control equations of the circular HSLA steel plate are presented by utilizing the principle of minimum potential energy. The entire problem is solved by utilizing the finite difference method, Newmark method and iterative method. Numerical results show that mechanical loads, boundary conditions, the ratio of thickness to radius, and temperature field have a great influence on thermoviscoelastic behavior of the circular HSLA steel plate.

In this article, dynamic thermoelastic behavior of a double-layered cylinder with an FGM layer under mechanical and thermal loadings are investigated. The double-layered hollow cylinder is constructed by an FGM layer and a homogenous layer. Utilizing the Finite difference method and Newmark method, the governing equation of the double-layered hollow cylinder under both dynamic mechanical and thermal loads is solved. The accuracy of the approach is validated by comparing the results with the existing analytical ones. Numerical results show that volume exponent of the FGM layer, the thickness ratio of two layers and temperature change have significant effect on the dynamic behaviors of the double-layered hollow cylinder.

Manganese picrate with 2,6-bis(benzimidazol-2-yl)pyridine (L) has been prepared and characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction. The complex crystallizes in the triclinic system, space group P–1 with a = 14.234(3) A, b = 14.324(2) A, c = 15.242(2) A, α = 77.569(2)°, β = 63.350(3)°, γ = 82.130(2)°, and Z = 2. Interaction of the complex with calf-thymus DNA (CT-DNA) has been investigated with diverse spectroscopic techniques and viscosity measurements, and the binding constant is 1.76 × 105 mol−1. Results suggest that the complex bind to CT-DNA via intercalation.

Immunohistochemical synovial tissue biomarkers are used increasingly to classify arthropathies, study their pathogenesis, and to measure disease activity in clinical trials. We have used receiver operating characteristic (ROC) analysis to quantify the discriminatory abilities of markers for common inflammatory cells (subintimal CD15, CD68, CD3, CD20, CD38, and lining CD68), proliferating cells (Ki-67) and blood vessels (von Willebrand factor, vWF) among inflammatory (chronic septic arthritis, early arthritis and rheumatoid arthritis (RA)) and degenerative arthropathies (osteoarthritis (OA) and orthopedic arthropathies) and normal synovium. Six of the eight markers distinguished accurately between RA and the degenerative arthropathies (area under the curve (AUC) 0.91-0.97), whereas subintimal CD68 (AUC 0.92) and Ki-67 (AUC 0.87) distinguished best between OA and normal synovium. Fold differences in mean expression correlated only modestly with AUCs (r(2) = 0.44). Multicategory ROC analysis ranked Ki-67, subintimal CD68, and CD15 as discriminating best among all six sample groups, and thus identified them as the most broadly applicable markers.

An analytical method is developed to determine the transient response of magneto-thermostress and perturbation of the magnetic field vector produced in orthotropic laminated hollow cylinders subjected to thermal shock, and permeated by a primarily uniform magnetic field. A magnetothermostress equation for each separate hollow cylinder is found by making use of a series of simply mathematical transform. Then, by using the interface continuity conditions between layers and the boundary conditions at the internal and external surfaces of the orthotropic laminated hollow cylinders, the unknown constants involved are determined. Thus, an exact expression for the magnetothermostress wave propagation and the perturbation response of magnetic field vector in the orthotropic laminated hollow cylinders are obtained. From sample numerical calculations, some characters of magnetothermodynamic stresses and perturbation of magnetic field vector in orthotropic laminated hollow cylinders are revealed and discussed.

This article reveals some phenomena of the dynamic focusing effects of laminated composites with piezoelectric fiber and matrix layer, subjected to thermal shock of a transitory temperature change, by means of an exact analytical solution and the corresponding numerical example. The dynamic focusing effects give rise to much higher tensile stress magnitudes and electric potential at the center or at near the center of the piezoelectric fiber-reinforced composites system, which easily results in breakage along the axial direction of the piezoelectric fiber at the higher tensile stress region. From the analytical expression and numerical example for the piezoelectric fiber reinforced composites system PZT-4/Matrix, it is important to know the mechanism of the dynamic focusing effect of the piezoelectric fiber reinforced composites system and to evaluate the dynamic strength and electric signal of the laminated composites with piezoelectric fiber.

Based on the Whitcomb delaminated buckling model, a Rayleigh-Ritz analysis is presented to study the local thermal buckling problem of elliptical, rectangular, triangular, and lemniscate delaminations in a symmetric composite laminated plate. The critical temperatures of the laminated plate with various shaped local delaminations and different stacking patterns are obtained by utilizing the energy principle. The geometrical axis of various shapes of local delamination is arbitrary. The stacking sequence of base laminated plates is symmetric, but the stacking sequence of the sublayer is asymmetric. Finally, our experimental study on the mechanism of delaminated buckling failure in a laminated plate with a single elliptical and rectangular delamination near the surface of the laminated plate under thermal load was accomplished. Analytical predictions for the critical temperature yielding the local delamination buckling are shown to correlate well with experimental results for a number of different delaminat...

An investigation is carried out to understand the thermal buckling behavior of local delamination near the surface of fiber-reinforced laminated cylindrical shells and the delaminated growth. The shape of the delaminated region considered is elliptic and triangular. The direction of the fiber material's axis is arbitrary. The relationships between the critical thermal load and the geometrical and physical parameters of base laminated shells and sublaminated shells are described and some valuable conclusions are obtained. Finally, the possible expanding direction of the elliptic and triangular delaminated shape under thermal load is discussed.

A capacitive micropressure sensor with readout circuits on a single chip is fabricated using commercial 0.35μm complementary metal oxide semiconductor (CMOS) process and post‐processing. The main break through feature of the chip is the positioning of its readout circuits under the pressure sensor, allowing the chip to be smaller. Post‐processing included anisotropic dry etching and wet etching to remove the sacrificial layer, and the use of plasma enhanced chemical vapor deposition (PECVD) of nitride to seal the etching holes on the pressure sensor. The readout circuit is divided into analog and digital parts, with the digital part being an alternate coupled RS flip‐flop with four inverters that sharpened the output wave. The analog part employed switched capacitor methodology. The pressure sensor contained an 8×8 sensing cells array, and the total area of the pressure sensor chip is 2mm×2mm.

An electrostatic microwave switch has been implemented by applying surface micromachining processes. The substrate of the microwave switch is gallium arsenide (GaAs). The structure of the microwave switch contains a gold coplanar waveguide and a suspended aluminum membrane. The Al membrane is directly anchored to the sidewalls of the GaAs substrate. All processing temperatures are under 350°C. The microwave switch operation is controlled by electrostatic force. The experimental results of the microwave switch show a microwave isolation of ‐40 dB and an insertion loss of ‐0.5 dB in the range of 0.1 to 7 GHz. In addition to demonstrating the design and fabrication of the microwave switch, this work summarizes experimental results.

A capacitive pressure sensor has been implemented by the industrial standard 0.8μm CMOS (Complementary metal oxide semiconductor) process. The device layout follows the entire set of CMOS IC (Integrated circuit) design rules. The sensing capacitor of the capacitive pressure sensor is composed of the upper metal (metal 2) and the polysilicon layer. The lower metal layer (metal 1) serves as the sacrificial layer. After completing the standard CMOS process, three CMOS‐compatible post‐processing steps were applied. First, phosphoric acid was used to etch the sacrificial layer to release the membrane of the capacitive pressure sensor. Second, PECVD (Plasma enhanced chemical vapor deposition) nitride was utilized to seal all access holes. Finally, RIE (Reaction ion etching) was used to remove nitride on the membrane. The dimensions of the capacitive pressure sensor are 1.0mm×0.9mm. This pressure sensor operates linearly in the range of 0 ∼ 200kPa, and the sensitivity is 0.07mV/kPa.

The implementation of pointer-type micro strain gauges requires the use of standard CMOS process (Complementary Metal Oxide Semiconductor). To determine residual strain of thin films, micro strain ...

A capacitive accelerometer integrated with a switched-capacitor circuitry on the same chip has been implemented by using a 0.8μm DPDM (Double Polysilicon Double Metal) CMOS process. We will explain the working principle of the capacitive accelerometer, and describe the design and the post-processing of the capacitive CMOS accelerometer chip. Metal 1 layer is selected as the sacrificial layer. The sensing capacitor of the capacitive accelerometer is composed of poly 1 layer and metal 2 layer. The post-CMOS processing steps need one mask only, and phosphoric acid is used to etch the sacrificial layer for releasing the suspended structure. A switched-capacitor circuitry is for the use of detecting the output signal of the accelerometer. The performance of this CMOS accelerometer demonstrates a bandwidth of 150Hz and an working range of ±15g with a sensitivity of 120μV/g.