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1

Vibration Equations of Thick Rectangular Plates Using Mindlin Plate Theory  

Microsoft Academic Search

Problem statement: Rectangular steel plates are widely used in variou s steel structures and steel industries. For a proper design of steel plate structures and efficient use of material, the behavior, strength, buckling and post-buckling char acteristics of plates should be accurately determined. Approach: Considering the significance of this matter, later al vibration of thick rectangular plates was studied on

S. A. Sadrnejad; A. Saedi Daryan; M. Ziaei

2

Diffraction phenomena inside thick Fresnel zone plates  

Microsoft Academic Search

The parabolic wave equation method is used to describe the complex wave field inside the body of a thick zone plate used to focus X ray radiation. Two analytical approaches are applied: (1) Diffraction of a plane wave incident onto a separate interface between opaque and open zones is considered. We construct an approximate analytical solution to the classical problem

Yuri V. Kopylov; Alexei V. Popov; Alexander V. Vinogradov

1996-01-01

3

Variable thickness double-refracting plate  

DOEpatents

This invention provides an A.C., cyclic, current-controlled, phase retardation plate that uses a magnetic clamp to produce stress birefringence. It was developed for an Isotope-Zeeman Atomic Absorption Spectrometer that uses polarization modulation to effect automatic background correction in atomic absorption trace-element measurements. To this end, the phase retardation plate of the invention is a variable thickness, photoelastic, double-refracting plate that is alternately stressed and released by the magnetic clamp selectively to modulate specific components selected from the group consisting of circularly and plane polarized Zeeman components that are produced in a dc magnetic field so that they correspond respectively to Zeeman reference and transmission-probe absorption components. The polarization modulation changes the phase of these polarized Zeeman components, designated as .sigma. reference and .pi. absorption components, so that every half cycle the components change from a transmission mode to a mode in which the .pi. component is blocked and the .sigma. components are transmitted. Thus, the Zeeman absorption component, which corresponds in amplitude to the amount of the trace element to be measured in a sample, is alternately transmitted and blocked by a linear polarizer, while the circularly polarized reference components are continuously transmitted thereby. The result is a sinusoidally varying output light amplitude whose average corresponds to the amount of the trace element present in the sample.

Hadeishi, Tetsuo (Berkeley, CA)

1976-01-01

4

Thermoelastic buckling behavior of thick functionally graded rectangular plates  

Microsoft Academic Search

Thermoelastic buckling behavior of thick rectangular plate made of functionally graded materials is investigated in this article.\\u000a The material properties of the plate are assumed to vary continuously through the thickness of the plate according to a power-law\\u000a distribution. Three types of thermal loading as uniform temperature raise, nonlinear and linear temperature distribution through\\u000a the thickness of plate are considered.

M. Bodaghi; A. R. Saidi

2011-01-01

5

Polynomial and harmonic differential quadrature methods for free vibration of variable thickness thick skew plates  

Microsoft Academic Search

An examination of the accuracy and convergence behaviors of polynomial basis function differential quadrature (PDQ) and harmonic basis function differential quadrature (HDQ) for free vibration analysis of variable thickness thick skew plates will be carried out. The plate governing equations are based on the first-order shear deformation theory including the effects of rotary inertia. Arbitrary thickness variations will be assumed

P. Malekzadeh; G. Karami

2005-01-01

6

49 CFR 179.400-8 - Thickness of plates.  

Code of Federal Regulations, 2011 CFR

...calculated by the following formula, whichever is greater: t = Pd / 2SE Where: t = minimum thickness of plate, after forming...by the following formula, whichever is greater: t = 1.83 Pd / 2SE Where: t = minimum thickness of plate, after...

2011-10-01

7

49 CFR 179.400-8 - Thickness of plates.  

Code of Federal Regulations, 2012 CFR

...calculated by the following formula, whichever is greater: t = Pd / 2SE Where: t = minimum thickness of plate, after forming...by the following formula, whichever is greater: t = 1.83 Pd / 2SE Where: t = minimum thickness of plate, after...

2012-10-01

8

Oblique Perforation of Thick Metallic Plates by Rigid Projectiles  

Microsoft Academic Search

Oblique perforation of thick metallic plates by rigid projectiles with various nose shapes is studied in this paper. Two perforation mechanisms, i.e., the hole enlargement for a sharp projectile nose and the plugging formation for a blunt projectile nose, are considered in the proposed analytical model. It is shown that the perforation of a thick plate is dominated by several

Xiaowei Chen; Qingming Li; Saucheong Fan

2006-01-01

9

Plate Thickness Variation Effects on Crack Growth Rates in 7050-T7451 Alloy Thick Plate  

NASA Astrophysics Data System (ADS)

A study has been accomplished to characterize the fatigue crack growth rates and mechanisms in thick plate (16.51 cm) commercial grade 7050-T7451 aluminum plate in the L-S orientation. Examination of the effects of potential property gradients in the plate material was accomplished through hardness measurements along the short transverse direction and with compact tension tests. Tests exhibited a distinct trend of reduced center plane hardness in the plates. Compact tension specimens and the compliance method were used to determine crack growth rates for specimens machined from the t/4 and t/2 planar locations and oriented for L-S crack growth. Crack growth rate data (long crack) from the tests highlighted significant growth rate differences between the t/4 and t/2 locations. No significant effect of R-ratio was observed in the 0.05-0.3 range tested. Additionally, crack front splitting was noted in all specimens to differing degrees with data showing significant retardation of growth rate curves for the L-S orientation above 13 MPa ?m in the center plane, and 10 MPa ?m at quarter plane, where branching and splitting parallel to the load axis are dominant growth mechanisms.

Schubbe, Joel J.

2011-02-01

10

Accurate vibration analysis of thick, cracked rectangular plates  

Microsoft Academic Search

This work applies the Ritz method to accurately determine the frequencies and nodal patterns of thick, cracked rectangular plates analyzed using Mindlin plate theory. Two types of cracked configuration are considered, namely, side crack and internal crack. To enhance the capabilities of the Ritz method in dealing with cracked plates, new sets of admissible functions are proposed to represent the

C. S. Huang; A. W. Leissa; R. S. Li

2011-01-01

11

Natural frequencies of orthotropic rectangular plates with stepped thickness  

Microsoft Academic Search

It is shown how one can derive an approximate formula for estimating a natural frequency of an orthotropic rectangular plate with stepped thickness by using several natural frequencies of the corresponding isotropic plate reduced from the orthotropic one. To justify the method, an orthotropic two-part rectangular plate with simply supported sides is discussed, and an approximate formula is proposed for

T. Sakata

1981-01-01

12

Thickness dependence of the Casimir force between a magnetodielectric plate and a diamagnetic plate  

SciTech Connect

This paper examines the repulsive Casimir force between a magnetodielectric plate, with static permeability greater than static permittivity, and a diamagnetic plate. As the thickness of the magnetodielectric plate is decreased, the attractive component of the Casimir force decreases more than the repulsive one. This effect makes the net Casimir force repulsive, and a larger repulsive Casimir force is generated compared to the Casimir force between the plates with infinite thickness.

Inui, Norio [Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji, Hyogo, 671-2201 (Japan)

2011-11-15

13

49 CFR 179.220-6 - Thickness of plates.  

Code of Federal Regulations, 2011 CFR

...Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION...Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.220-6...179.220-9 for plate thickness requirements for inner container when divided...

2011-10-01

14

A refined theory of elastic thick plates for extensional deformation  

Microsoft Academic Search

Based on elasticity theory, various two-dimensional (2D) equations and solutions for extensional deformation have been deduced\\u000a systematically and directly from the three-dimensional (3D) theory of thick rectangular plates by using the Papkovich–Neuber\\u000a solution and the Lur’e method without ad hoc assumptions. These equations and solutions can be used to construct a refined\\u000a theory of thick plates for extensional deformation. It

Yang Gao; Bao-Sheng Zhao

2009-01-01

15

A spectroscopic method for determining thickness of quartz wave plate  

Microsoft Academic Search

A spectroscopic method to determine thickness of quartz wave plate is presented. The method is based on chromatic polarization interferometry. With the polarization-resolved transmission spectrum (PRTS) curve, the phase retardation of quartz wave plate can be determined at a wide spectral range from 200 to 2000 nm obviously. Through accurate judgment of extreme points of PRTS curve at long-wave band,

Weiwei Feng; Lihuang Lin; Ligang Chen; Huafeng Zhu; Ruxin Li; Zhizhan Xu

2006-01-01

16

Vibration analysis of moderate-thick plates with slowly varying thickness  

Microsoft Academic Search

In this paper, the flexural vibration analysis of moderate-thick rectangular plates with slowly varying thickness using perturbation method is described, and the explict expressions of free vibration frequencies for arbitrary thickness functions are derived. Finally, several numerical examples have been given and comparisons have been made with other proposed solution techniques. This comparison shows that the method yields very good

Li Long-yuan

1986-01-01

17

Vibration of a sandwich plate strip of linearly varying thickness  

Microsoft Academic Search

Free transverse vibration of a sandwich plate strip having a core of linearly varying thickness and symmetrical faces of constant thickness is considered. The materials of the core and the faces are assumed to be linearly elastic and isotropic. The effects of transverse shear deformation and rotary inertia are included in the core as well as in the faces. The

A. P. Gupta; R. R. Bhargava

1993-01-01

18

Perforation of medium thick plate by a sharp projectile  

Microsoft Academic Search

The paper predicts the ballistic performance of the normal perforation of a medium thick plate by a rigid projectile with sharp nose. Ductile hole- enlargement is the failure mechanism in the perforation process. It shows that the analytical formulae depend only on three dimensionless numbers, i.e., the dimensionless target thickness ´, the dimensionless impact function I and geometry function N

X. W. Chen; Q. M. Li; Y. Z. Chen

2005-01-01

19

Oblique Perforation of Thick Metallic Plates by Rigid Projectiles  

NASA Astrophysics Data System (ADS)

Oblique perforation of thick metallic plates by rigid projectiles with various nose shapes is studied in this paper. Two perforation mechanisms, i.e., the hole enlargement for a sharp projectile nose and the plugging formation for a blunt projectile nose, are considered in the proposed analytical model. It is shown that the perforation of a thick plate is dominated by several non-dimensional numbers, i.e., the impact function, the geometry function of projectile, the non-dimensional thickness of target and the impact obliquity. Explicit formulae are obtained to predict the ballistic limit, residual velocity and directional change for the oblique perforation of thick metallic plates. The proposed model is able to predict the critical condition for the occurrence of ricochet. The proposed model is validated by comparing the predictions with other existing models and independent experimental data.

Chen, Xiaowei; Li, Qingming; Fan, Saucheong

2006-08-01

20

An advanced theory of moderately thick plate vibrations  

NASA Astrophysics Data System (ADS)

In thick plate vibration theory, the governing equations are stated with a system of three partial differential equations of motion with total deflection, which consists of bending deflection and shear contribution, and angles of rotation as fundamental variables. Most of the methods deal with these three equations, some of them with two, and recently a solution based on one equation has been offered. In the present paper, a system of three equations for a moderately thick plate is reduced to a single equation in terms of bending deflection only as a fundamental variable. Shear deflection and angles of rotation depend on bending deflection as a potential function. A simple formula for natural frequencies of a simply supported plate is derived. A characteristic equation is also obtained for a plate with simply supported two opposite edges. Numerical results for a simply supported plate and a plate clamped on the two remaining opposite edges are compared with those known in literature, for different aspect ratios and relative thickness, and very good agreement is achieved.

Senjanovi?, Ivo; Vladimir, Nikola; Tomi?, Marko

2013-04-01

21

Nonlinear Mindlin plate equations for the thickness-shear vibrations of crystal plates  

Microsoft Academic Search

Mindlin plate equations have wide applications in engineering fields with piezoelectric crystal resonators in particular due to its accurate prediction of high frequency vibrations of plates in the vicinity of thickness-shear mode. As a linear theory based on the assumption of infinitesimal deformation, its applications have been limited mainly to vibration frequency analysis. Many important properties of quartz crystal resonators

Ji Wang; Rong-xing Wu; Jian-ke Du; De-jin Huang; Hong-ping Hu; Yuan-tai Hu

2008-01-01

22

Perforation of a thick plate by rigid projectiles  

Microsoft Academic Search

Perforation of a thick plate by rigid projectiles with various geometrical characteristics is studied in the present paper. The rigid projectile is subjected to the resistant force from the surrounding medium, which is formulated by the dynamic cavity expansion theory. Two perforation mechanisms, i.e., the hole enlargement for a sharp projectile nose and the plugging formation for a blunt projectile

X. W. Chen; Q. M. Li

2003-01-01

23

Three-dimensional vibrations of annular thick plates with linearly varying thickness  

Microsoft Academic Search

The free vibration of annular thick plates with linearly varying thickness along the radial direction is studied, based on\\u000a the linear, small strain, three-dimensional (3-D) elasticity theory. Various boundary conditions, symmetrically and asymmetrically\\u000a linear variations of upper and lower surfaces are considered in the analysis. The well-known Ritz method is used to derive\\u000a the eigen-value equation. The trigonometric functions in

D. Zhou; S. H. Lo

24

Accurate vibration analysis of thick, cracked rectangular plates  

NASA Astrophysics Data System (ADS)

This work applies the Ritz method to accurately determine the frequencies and nodal patterns of thick, cracked rectangular plates analyzed using Mindlin plate theory. Two types of cracked configuration are considered, namely, side crack and internal crack. To enhance the capabilities of the Ritz method in dealing with cracked plates, new sets of admissible functions are proposed to represent the behaviors of true solutions along the crack. The proposed admissible functions appropriately describe the stress singularity behaviors around a crack tip and the discontinuities of transverse displacement and bending rotations across the crack. The present solutions monotonically converge to the exact frequencies as upper bounds when the number of admissible functions increases. The validity and accuracy of the present solutions are confirmed through comprehensive convergence studies and comparison with the published results based on the classical thin plate theory. The proposed approach is further employed to investigate the effects of the length, location, and orientation of crack on frequencies and nodal patterns of simply supported and cantilevered cracked rectangular plates. The results shown are the first ones available in the published literature.

Huang, C. S.; Leissa, A. W.; Li, R. S.

2011-04-01

25

Guided acoustic emission waves in a thick composite plate  

NASA Astrophysics Data System (ADS)

In this paper, an efficient and accurate semi-analytical method based on the wavenumber integral representation of the elastodynamic field is described to calculate the surface responses produced by localized dynamic loads in a relatively thick composite plate. Two types of loads are considered: a pencil lead break source located on the surface and a localized shear delamination within the interior of the plate. In the case of the pencil lead break source, the calculated results for the surface motion are compared with those obtained in laboratory experiments on a 4.4 mm thick 32 layered cross-ply graphite/epoxy using high-fidelity broad band transducers. The waveforms consist of both flexural and extensional modes; the amplitude variations of these modes are found to be strongly dependent on their propagation direction. For the delamination source at the mid plane, the results from the exact calculation are compared with those from an approximate laminate theory with shear correction factor and "moment tensor" representation of the source. The results obtained by the two methods are shown to have excellent agreement in the low frequency ranges. Although, the motion due to the delamination is dominated by flexural waves of lower frequency in both thin and thick plates, the presence of extensional waves are observed in thicker laminates. The acoustic emission waveforms from the initiation of a shear delamination source at various interfaces are also calculated. It is found that the amplitude of the flexural modes decreases and that of the extensional modes increases as the source moves farther away from the mid plane.

Mal, Ajit K.; Banerjee, Sauvik

2004-07-01

26

Vibration of non-uniform thick plates on elastic foundation by differential quadrature method  

Microsoft Academic Search

This paper presents a differential quadrature (DQ) solution for free vibration analysis of thick plates of continuously varying thickness on two-parameter elastic foundations. The formulations are based on the first-order shear deformation theory taking into account the effects of rotary inertia. The thickness of the plate may vary in one or two directions. The thickness variation might be assumed linear

P. Malekzadeh; G. Karami

2004-01-01

27

Stress concentration factors due to the bending of a thick plate with circular hole  

Microsoft Academic Search

Solutions of a biharmonic equation together with four Helmholtz equations governing a twelfthorder thick plate theory in cylindrical coordinates are derived in a form suitable for finding corrections to previous lower-order thick plate results. As an example, for an infinite plate with a circular hole subjected to bending moments at two parallel outside edges, detailed comparisons of values of a

P. S. Chen; R. R. Archer

1989-01-01

28

Solution Procedure for Behavior of Thick Plates on a Nonlinear Foundation and Postbuckling Behavior of Long Plates.  

National Technical Information Service (NTIS)

Approximate solutions for three nonlinear orthotropic plate problems are presented: (1) a thick plate attached to a pad having nonlinear material properties which, in turn, is attached to a substructure which is then deformed; (2) a long plate loaded in i...

M. Stein P. A. Stein

1978-01-01

29

Standards for organic contaminant thickness measurement by the ellipsometer  

SciTech Connect

No film thickness standards have been established for the ellipsometer that can be used for determining the thickness of organic contaminants on electrical components. Thickness measurement of organic contamination on a surface is dependent on the refractive index of the film; knowledge of the refractive index of the film is required before thickness measurements can be made. Silicon oxide has a refractive index equivalent to most organic materials. Silicon oxide, therefore, can be used for developing thickness standards for use in ellipsometer measurement of organic film contamination. A film thickness standard curve was established by correlating known silicon oxide thicknesses with their corresponding phase change (delta, an optical constant of the surface). Thickness standards up to 2700 A were established.

Jackson, L.C.

1981-03-01

30

Guided waves in a plate with linearly varying thickness: experimental and numerical results  

Microsoft Academic Search

The aim of this work is to give experimental and numerical results on the behaviour of guided waves that propagate downslope in a free elastic plate with slowly linearly varying thickness. We show experimentally the propagation of adiabatic modes, which are guided waves that adapt to the varying thickness of the plate. As the thickness is decreasing, a given guided

M. Ech-Cherif El-Kettani; F Luppé; A Guillet

2004-01-01

31

The nonlinear thickness-shear vibrations of an infinite and isotropic elastic plate  

Microsoft Academic Search

Thickness-shear vibrations of a plate is one of the most widely used functioning modes of quartz crystal resonators. For an analysis of vibrations, the Mindlin and Lee plate theories based on the displacement expansion of the thickness coordinate have been used as the linear theories. However, due to lacking of available method and complexity of the problem, the nonlinear thickness-shear

Ji Wang; Rong-xing Wu; Jian-ke Du

2009-01-01

32

Optimal stiffener design of moderately thick plates under uniaxial and biaxial compression  

Microsoft Academic Search

In this paper, the optimal stiffener design of moderately thick plates under uniaxial and biaxial compression is investigated on the premise that the plate thickness and the required ultimate strength are given. As the theoretical basis of stiffener design, the ultimate strength formulations of weak stiffened thick panels under in-plane biaxial compression are first developed on the basis of large

Bin Cheng; Rucheng Xiao; Jincheng Zhao; Jin Cheng

2010-01-01

33

Compressible flow of gases: Pressure losses and discharge coefficients of orifice plates, perforated plates and thick orifice plates in ducts  

NASA Astrophysics Data System (ADS)

This Data Item is available as part of the ESDU Sub-series on Fluid Mechanics Internal Flow. Pressure loss and discharge coefficient data for subsonic compressible flow of gases through single or multiple, sharp-edged orifices in thin or thick plates for flow rates up to choking are presented. The mechanics of compressible flow through orifices are discussed briefly with particular attention to sonic flow conditions. The mass flow function, based on orifice entry conditions, that gives maximum mass flow rate is presented and pressure loss coefficients are then expressed as a function of actual mass flow function to this limiting value. All are functions also of porosity and thickness/diameter ratio of the orifice. The data cover a range of porosity between 0.001 and 0.95 and thickness/diameter up to seven.

1982-04-01

34

An analytical solution for buckling of moderately thick functionally graded sector and annular sector plates  

Microsoft Academic Search

In this article, an analytical solution for buckling of moderately thick functionally graded (FG) sectorial plates is presented.\\u000a It is assumed that the material properties of the FG plate vary through the thickness of the plate as a power function. The\\u000a stability equations are derived according to the Mindlin plate theory. By introducing four new functions, the stability equations\\u000a are

A. Naderi; A. R. Saidi

2011-01-01

35

Three-dimensional elastic stress fields ahead of blunt V-notches in finite thickness plates  

Microsoft Academic Search

Based on detailed three-dimensional (3D) finite element analyses, elastic fields in front of blunt V-notches in finite thickness plates subjected to uniaxial far-end tensile stress have been investigated. By comparison with the corresponding planar V-notch fields and 3D through-thickness sharp crack fields, various aspects of the 3D fields of the blunt V-notches in finite thickness plates are revealed: (1) The plate

Zhenhuan Li; Wanlin Guo

2001-01-01

36

49 CFR 179.220-6 - Thickness of plates.  

Code of Federal Regulations, 2012 CFR

... PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION... S = Minimum tensile strength of plate material in p.s.i. as prescribed... S = Minimum tensile strength of plate material in psi as prescribed...

2012-10-01

37

49 CFR 179.200-6 - Thickness of plates.  

Code of Federal Regulations, 2011 CFR

... S = Minimum tensile strength of plate material in p.s.i. as prescribed... S = Minimum tensile strength of plate material in p.s.i. as prescribed... S = Minimum tensile strength of plate material in p.s.i. as...

2011-10-01

38

49 CFR 179.200-6 - Thickness of plates.  

Code of Federal Regulations, 2012 CFR

... S = Minimum tensile strength of plate material in p.s.i. as prescribed... S = Minimum tensile strength of plate material in p.s.i. as prescribed... S = Minimum tensile strength of plate material in p.s.i. as...

2012-10-01

39

46 CFR 32.59-1 - Minimum section modulus and plating thickness requirements-TB/ALL.  

Code of Federal Regulations, 2010 CFR

...modulus and plating thickness requirements-TB/ALL. 32.59-1 Section 32.59-1...Vessels That Carry Certain Oil Cargoes-TB/ALL § 32.59-1 Minimum section modulus and plating thickness requirementsâTB/ALL. (a) As used in this...

2010-10-01

40

46 CFR 32.59-1 - Minimum section modulus and plating thickness requirements-TB/ALL.  

Code of Federal Regulations, 2010 CFR

...modulus and plating thickness requirements-TB/ALL. 32.59-1 Section 32.59-1...Vessels That Carry Certain Oil Cargoes-TB/ALL § 32.59-1 Minimum section modulus and plating thickness requirementsâTB/ALL. (a) As used in this...

2009-10-01

41

An analog equation solution to dynamic analysis of plates with variable thickness  

Microsoft Academic Search

The analog equation method (AEM) is applied to dynamic analysis of plates with variable thickness. Both free and forced vibrations are considered. The fourth order partial differential equation with variable coefficients governing the dynamic response of the plate is converted to a quasi-static plate bending problem under a fictitious time dependent load. The fictitious load is established using the AEM.

M. S. Nerantzaki; J. T. Katsikadelis

1996-01-01

42

A high-sensitivity, dual-plate, thickness-shear mode pressure sensor.  

PubMed

We propose a dual-plate pressure sensor operating with pressure-induced frequency shifts of thickness-shear modes of a crystal plate resonator. Under an applied normal pressure. The dual-plate structure causes flexure in the crystal plate rather than circumferential compression in usual thickness-shear pressure sensors. This suggests higher sensitivity because a plate responds to a normal pressure more than to a circumferential compression, which is shown by a theoretical analysis using the theory for small fields superposed on initial fields. PMID:17091855

Hu, Yuantai; Yang, Jiashi; Zeng, Yun; Jiang, Qing

2006-11-01

43

Properties of superconducting thick films formed on electroless copper plated ceramic substrates  

Microsoft Academic Search

Forming of thick film superconductors of Bi-type on various ceramic which were plated with copper by electroless plating method, were attempted. As the result, adhesive strength of thick film which was formed on MgO ceramic substrate was so high as about 200 kg\\/cm, and achieved the success for obtaining excellent thick film superconductor with critical temperature of 102 K and

Kunihiro Nagata

1992-01-01

44

Variation in Effective Elastic Plate thickness of the East African Lithosphere  

NASA Astrophysics Data System (ADS)

A compilation of new and existing Bouguer gravity and topographic data from East Africa is presented. These datasets were processed using the coherence method to derive the effective elastic plate thickness. Using these results, we investigate the long-term flexural rigidity of the lithosphere. Four tectonic provinces are characterized by distinct effective elastic plate thicknesses. These are: the Tanzanian Craton, the Proterozoic Mobile Belts, the Paleogene rift basins in Sudan and Kenya, and the East African Rift System. Beneath the Tanzanian craton, the elastic plate thickness is ca 75 km, while the Pan African Mobile Belts and the Ubendian Belt, are ca 55 and 65 km, respectively. The Paleogene rift basins exhibit an elastic plate thickness varying between 40 and 45 km. The effective elastic plate thickness within the faulted East African Rift System ranges from 14 km in the north to 33 km in the south. The minimum is found beneath the active rift of the Afar depression. The north to south along-rift-axis variation in effective elastic plate thickness can be attributed to contrasts in the mechanical strength of the lithosphere. This is consistent with the north-south decrease in extensional velocity and northward decrease in the focal depth of the earthquakes, reflecting a northward thinning in the brittle layer of the crust. The maximum effective elastic plate thickness is found beneath the Tanzanian craton, while the surrounding Mobile Belts have relatively moderate elastic plate thicknesses. The high effective elastic plate thickness below the Tanzanian craton suggests that this part of the lithosphere is rheologically competent compared to the surrounding Mobile Belts. The craton effectively resists deformation, even though it is located within a broad zone of an east-west extensional tectonic regime. Consequently, it has altered the direction of the rift propagation into the warmer and weaker lithosphere of the surrounding Mobile Belts.

Tessema, A.; Antoine, L. A.

2003-04-01

45

Inductance of a coil on a thick ferromagnetic metal plate  

Microsoft Academic Search

We study the frequency-dependent inductance of a small air-cored coil of wire placed flat upon various ferromagnetic metal plates. The change in the complex inductance of the coil, measured with an HP 4193A impedance analyzer, is reported for frequencies between 1 kHz and 1 MHz. The metal plates consisted of commercially pure (99.7% and 99.9%) Ni, commercially pure (99.9%) Fe,

John C. Moulder; Cheng-Chi Tai; Brian F. Larson; James H. Rose

1998-01-01

46

Guided waves in a plate with linearly varying thickness: experimental and numerical results.  

PubMed

The aim of this work is to give experimental and numerical results on the behaviour of guided waves that propagate downslope in a free elastic plate with slowly linearly varying thickness. We show experimentally the propagation of adiabatic modes, which are guided waves that adapt to the varying thickness of the plate. As the thickness is decreasing, a given guided wave will reach its thickness cut-off. When this happens, we show that two phenomena occur: the reflection of this wave and its propagation backward in the plate, its conversion into a different guided wave which goes on propagating downslope in the plate. The numerical study is done with the software Ansys, based on the finite element method. The results obtained confirm the experimental ones. PMID:15047388

El-Kettani, M Ech-Cherif; Luppé, F; Guillet, A

2004-04-01

47

Three-dimensional elastic stress fields near notches in finite thickness plates  

Microsoft Academic Search

Based on detailed three-dimensional finite element (3D FE) analyses, elastic notch-root fields in plates with different thicknesses and notch configurations subjected to uniaxial tension have been investigated. By comparing with the planar notch-root fields and crack-tip fields, the following characteristics of the 3D stress–strain fields near the notch front are revealed: (1) The plate thickness and notch configuration have obvious

Zhenhuan Li; Wanlin Guo; Zhenbang Kuang

2000-01-01

48

Variation in effective elastic plate thickness of the East Africa lithosphere  

NASA Astrophysics Data System (ADS)

We use new and existing Bouguer gravity data to characterize the long-term flexural rigidity of the lithosphere beneath East Africa. Four tectonic provinces are characterized by distinct effective elastic plate thicknesses. These are the Tanzanian Craton, the Proterozoic Mobile Belts, the Paleogene rift basins in Sudan and Kenya, and the Cenozoic East African Rift System. Beneath the Tanzanian craton the elastic plate thickness is ˜75 km, while the Pan African Mobile Belts and the Ubendian Belts are ˜55 and ˜65 km, respectively. The Paleogene rift basins exhibit an elastic plate thickness varying between 40 and 45 km. The effective elastic plate thickness within the faulted East African Rift System ranges from 14 km in the north to 33 km in the south. The minimum is found beneath the active rift of the Afar depression. The north to south along-rift axis variation in effective elastic plate thickness can be attributed to contrasts in the mechanical strength of the lithosphere. This is consistent with the north-south decrease in extensional velocity and the northward decrease in the focal depths of the earthquakes, reflecting a northward thinning in the brittle layer of the crust. The maximum elastic plate thickness is found beneath the Tanzanian craton, while the surrounding Mobile Belts have relatively moderate elastic plate thicknesses. The high effective elastic plate thickness of the Tanzanian craton suggests that this part of the lithosphere is rheologically competent compared to the surrounding Mobile Belts. The craton effectively resists deformation, even though it is located within a broad zone of an east-west extensional tectonic regime. Consequently, it has altered the direction of the rift propagation into the warmer and weaker lithosphere of the surrounding Mobile Belts.

Tessema, A.; Antoine, L. A. G.

2003-05-01

49

Numerical and experimental studies on aluminum sandwich plates of variable thickness  

Microsoft Academic Search

The elastic flexural behavior of static deformation and free vibration of sandwich plates of variable thickness is investigated numerically and experimentally. In the analysis, the face plates are treated as Marguerre shells, and the core is assumed to be an antiplane core and to provide resistance to transverse shear and normal stresses only. Displacement continuity conditions are used at the

2006-01-01

50

Effects of layer thickness on the vibration response of a plate-fluid layer system  

Microsoft Academic Search

Dynamic interaction between the bending vibrations of a plate and a fluid layer is investigated by using analytical and experimental methods. The frequency response behavior of the coupled plate-fluid layer system is studied, with emphasis on the influence of the layer thickness. The effects of compressibility, viscosity, and inertia of the fluid are included in the analytical model. A critical

T. Onsay

1993-01-01

51

Temperature Dependent Fracture Model and its Application to Ultra Heavy Thick Steel Plate Used for Shipbuilding  

Microsoft Academic Search

In this study, experimental and numerical studies were performed to examine the effects of thickness of steel plate on the arrest fracture toughness. The ESSO tests were performed with the steel plates having temperature gradient along the crack propagation direction. A temperature dependent crack initiation criterion was proposed as well. A series of three-dimensional FEA was then carried out to

Yun Chan Jang; Youngseog Lee; Gyu Baek An; Joon Sik Park; Jong Bong Lee; Sung Il Kim

2008-01-01

52

A refined higher-order theory and its finite element method for thick laminated plates  

NASA Astrophysics Data System (ADS)

An improved higher-order theory developed to enhance the accuracy of the shear deformation theory of thick laminated plates is presented. The Legendre polynomials are introduced in the approximate displacement distributions across the plate thickness, and an FEM is suggested from the original equations. The accuracy of the present theory is examined by applying it to bending problems of laminate plates solved by Pagano. The results are compared with 3D elasticity solutions, the second order shear deformation theory, and some other higher-order shear deformation theory solutions. The present theory shows the deflections and stress more accurately than that obtained from previous works in the structural analysis of laminated plates with a small span with respect to thickness.

Fu, Xiaohua; Chen, Haoran; Wang, Zhenming

1992-04-01

53

Thickness Vibrations of Sandwich Plates and Beams and Delamination Detection  

Microsoft Academic Search

In multi-hull marine vehicles assembled by FRP sandwich composite materials, problems with delamination and skin\\/core debonding are reported. An early damage warning (EDW) system for delamination detection in marine vessels based on measurements of bending vibrations in sandwich structures are under development.Related to this EDW system development, this paper presents a theory for qualitative determination of thickness vibrations in sandwich

Alf Egil Jensen; Fridtjov Irgens

1999-01-01

54

Numerical investigations of maximum stress concentration at elliptic holes in finite thickness piezoelectric plates  

Microsoft Academic Search

The through-thickness variations of stress-concentration factors along the wall of elliptic holes in finite thickness plates of transversely isotropic piezoelectric materials subjected to uniaxial remote tensile stress and applied electric field have been systematically analyzed using the finite element method. The three-dimensional stress concentration factor Kt is found to be a function of the thickness to root radius ratio B\\/?

Chongmin She; Wanlin Guo

2006-01-01

55

Transverse vibration of viscoelastic rectangular plate with linearly varying thickness and multiple cracks  

NASA Astrophysics Data System (ADS)

Based on the thin-plate theory and the two-dimensional viscoelastic differential constitutive relation, the differential equations of motion of the viscoelastic plate with linearly varying thickness and an arbitrary number of all-over part-through cracks are established, and the expressions of the additional rotation angle induced by the cracks are deduced. We assume that it is elastic in dilatation, but postulate the Kelvin Voigt laws for distortion, the complex eigenvalue equations of the viscoelastic plate with linearly varying thickness and multiple cracks are derived by the differential quadrature method. The general eigenvalue equations of the viscoelastic plate with multiple cracks under different boundary conditions are calculated. The effects of various geometric parameters, dimensionless delay time and dimensionless crack parameters on the transverse vibration characteristics of a viscoelastic plate containing multiple all-over part-through cracks are analyzed.

Wang, Yan; Wang, Zhong-Min

2008-12-01

56

A locking-free meshless local Petrov Galerkin formulation for thick and thin plates  

NASA Astrophysics Data System (ADS)

In this paper, a locking-free meshless local Petrov Galerkin formulation is presented for shear flexible thick plates, which remains theoretically valid in the thin-plate limit. The kinematics of a three-dimensional solid is used, instead of the conventional plate assumption. The local symmetric weak form is derived for cylindrical shaped local sub-domains. The numerical characteristics of the local symmetric weak form, in the thin plate limit, are discussed. Based on this discussion, the shear locking is theoretically eliminated by changing the two dependent variables in the governing equations. The moving least square interpolation is utilized in the in-plane numerical discretization for all the three displacement components. In the thickness direction, on the other hand, a linear interpolation is used for in-plane displacements, while a hierarchical quadratic interpolation is utilized for the transverse displacement, in order to eliminate the thickness locking. Numerical examples in both the thin plate limit and the thick plate limit are presented, and the results are compared with available analytical solutions.

Li, Q.; Soric, J.; Jarak, T.; Atluri, S. N.

2005-09-01

57

Characterization of Fracture and Fatigue Behavior of 7050 Aluminum Alloy Ultra-thick Plate  

NASA Astrophysics Data System (ADS)

The microstructure, mechanical property, fracture toughness, and fatigue behavior of 7050 aluminum alloy pre-stretched ultra-thick plate were investigated by means of optical microscopy, scanning electron microscopy, transmission electron microscopy, tensile test, fracture toughness test, and high-cycle fatigue test. The results showed that the microstructure of the ultra-thick plate consisted of recrystallized grains, subgrains, constituent particles, precipitated phases, and precipitate-free zone. Mechanical tests indicated that anisotropy of fracture toughness existed in L-T, T-L, and S-T orientation. Fractographic features suggested that this anisotropy was significant due to the difference of recrystallized grain on different metallographic planes. Compared to 7050 aluminum alloy plate in less thickness, the ultra-thick plate showed deterioration on fracture toughness due to the increase of recrystallized grains but improvement on fatigue property ascribed to the less densely populated particles. Fractographic observations showed that fatigue initiation of this ultra-thick plate was primarily related to the constituent particles and promoted by increase of the stress amplitude.

Wei, Lili; Pan, Qinglin; Wang, Yilin; Feng, Lei; Huang, Hongfeng

2013-09-01

58

Thickness effects on the plastic collapse of perforated plates with triangular penetration patterns  

SciTech Connect

This paper investigates the effects of plate thickness on the accuracy of limit load solutions obtained using an elastic-perfectly plastic [EPP] equivalent solid [EQS] procedure for flat perforated plates with a triangular array of penetrations. The EQS approach for limit loads is based on an EQS collapse surface that is valid for generalized plane strain. This assumption is applicable for very thick plates but is known to be less reasonable for very thin plates where plane stress may be a better assumption. The limits of applicability of the generalized plane strain assumption are investigated by obtaining limit load solutions for perforated plates of various thicknesses that are subjected to in-plane and bending loads. Plastic limit load solutions obtained using three-dimensional EPP finite element analysis [FEA] of models which include each penetration explicitly are compared with solutions obtained using the EQS approximation. The penetration pattern chosen for this study has a ligament efficiency (ligament width-to-pitch ratio, h/P) of 0.32. For plates thicker than the pitch, the limit load calculated using the EQS method for both in-plane and bending loads is shown to be very accurate (within 4%) of the limit load calculated for the explicit model. On the other hand, for thin plates (t/P< 2), the EQS limit load is 5% greater than the explicit limit load for bending and 8% greater than the explicit limit load for in-plane loads. For thinner plates, the collapse surface is tied to the local geometry deformation and, hence, an equivalent solid plate representation of plastic collapse is a function of deformation mode and thickness.

Gordon, J.L.; Jones, D.P.; Holliday, J.E.

2000-03-01

59

Scattering from a periodic array of apertures or plates where the conductors have arbitrary shape, thickness, and resistivity  

NASA Astrophysics Data System (ADS)

The scattering properties of a periodic array of conductors having any shape composed of steps along the coordinate axes and illuminated by a plane wave are obtained through a rooftop current approximation. The solution, which involves a finite dimension matrix equation, is described along with an algorithm that efficiently generates the matrix elements. Results presented for arrays of rectangular apertures and thin, rectangular plates are shown to agree closely with those obtained through standard modal approaches. Convergence with respect to the number of current elements is also explored. Because the normal component of the edge current is nonzero and continuous when thickness is present, convergence is significantly better than for zero-thickness structures. At glancing incidence, however, accuracy requires a finer subsection grid to properly represent the circulating current on the sidewalls, for plates, and the U-shaped current flowing near the corner of the sidewalls, for apertures.

Rubin, Barry J.

1986-11-01

60

Benchmark solution for free vibration of functionally graded moderately thick annular sector plates  

Microsoft Academic Search

In the present article, an exact analytical solution for free vibration analysis of a moderately thick functionally graded\\u000a (FG) annular sector plate is presented. Based on the first-order shear deformation plate theory, five coupled partial differential\\u000a equations of motion are obtained without any simplification. Doing some mathematical manipulations, these highly coupled equations\\u000a are converted into a sixth-order and a fourth-order

A. R. Saidi; A. Hasani Baferani; E. Jomehzadeh

2011-01-01

61

Experimentation and modeling of inclined ballistic impact in thick polycarbonate plates  

Microsoft Academic Search

The penetration and perforation of a thick polycarbonate (PC) plate (one and 3 stacked) by an armor piercing 7.62 mm projectile is investigated experimentally and numerically. The characteristic structure of the projectile’s trajectory in the PC plates is studied. It is observed that the trajectory consist of a cavity and a circumferential cracked zone attached to it, which is fully embedded

A. Dorogoy; D. Rittel; A. Brill

2011-01-01

62

Effect of projectile nose shape, impact velocity and target thickness on deformation behavior of aluminum plates  

Microsoft Academic Search

The present study deals with the experimental and numerical investigations of aluminum target plates impacted by blunt, ogive and hemispherical nosed steel projectiles. The projectiles were normally impacted on the target plates of 0.5, 0.71, 1, 1.5, 2, 2.5 and 3mm thicknesses at different velocities with the help of a pneumatic gun. Effect of projectile nose shape, impact velocity and

N. K. Gupta; M. A. Iqbal; G. S. Sekhon

2007-01-01

63

Simultaneous measurement of refractive index and thickness of birefringent wave plates  

SciTech Connect

A nondestructive measurement system based on a position sensing detector (PSD) and a laser interferometer for determining the thickness and refractive indices of birefringent optical wave plates has been developed. Unlike previous methods presented in the literature, the proposed metrology system allows the refractive index and thickness properties of the optical plate to be measured simultaneously. The experimental results obtained for the e-light and o-light refractive indices of a commercially available birefringent optical wave plate with refractive indices of no=1.542972 and ne=1.552033 are found to be accurate to within 0.004132 and 0.000229, respectively. Furthermore, the experimentally derived value of the wave plate thickness deviates by no more than 0.9 {mu}m from the analytically derived value of 453.95 {mu}m. Overall, the experimental results confirm that the proposed metrology system provides a simple yet highly accurate means of obtaining simultaneous measurements of the refractive indices and thickness of birefringent optical wave plates.

Yeh, Y.-L

2008-04-01

64

Thickness-twist and face-shear waves in piezoelectric plates of monoclinic crystals.  

PubMed

We study the propagation of thickness-twist and face-shear waves in piezoelectric plates of monoclinic crystals, which include rotated Y-cut quartz and langasite as special cases. The equations of linear piezoelectricity are used. Exact solutions are obtained for both fully-electroded and unelectroded plates. Dispersion relations are plotted for both AT-cut quartz and Y-cut langasite plates. The difference in frequencies between the exact piezoelectric solutions obtained in the present paper and the approximate elastic solutions in the literature is found to be of the order of 1%, which is significant in acoustic wave resonator and sensor applications. PMID:23443714

Zhu, Jun; Chen, Weiqiu

2011-12-01

65

High-accuracy thickness measurement of a transparent plate with the heterodyne central fringe identification technique  

SciTech Connect

In a modified Twyman-Green interferometer, the optical path variation is measured with the heterodyne central fringe identification technique, as the light beam is focused by a displaced microscopic objective on the front/rear surface of the test transparent plate. The optical path length variation is then measured similarly after the test plate is removed. The geometrical thickness of the test plate can be calculated under the consideration of dispersion effect. This method has a wide measurable range and a high accuracy in the measurable range.

Wu, Wang-Tsung; Hsieh, Hung-Chih; Chang, Wei-Yao; Chen, Yen-Liang; Su, Der-Chin

2011-07-20

66

Analytical solution for free vibrations of moderately thick hybrid piezoelectric laminated plates  

NASA Astrophysics Data System (ADS)

An analytical solution for free vibrations of a hybrid rectangular plate composed of a transversely isotropic, homogeneous and linear elastic core and face sheets made of a linear piezoelectric material is derived by assuming that the plate deformations are governed by the Mindlin plate theory. The electric potential in a piezoelectric layer satisfies Maxwell's equation and either open circuit or closed circuit boundary conditions on its major surfaces. For the hybrid plate coupled governing equations obtained from the Hamilton principle are decoupled by introducing four auxiliary scalar functions, and the Levy type analytical solution for free vibrations is derived. Plate frequencies as a function of the piezoelectric layer thickness and the plate aspect ratio are presented and discussed. It is found that the electric boundary conditions on major surfaces of the piezoelectric layers and the aspect ratio of the hybrid plate noticeably influence its frequencies. Significant contributions of the work include proposing the four scalar functions to uncouple the governing equations, providing an analytical solution for frequencies of the hybrid plate, and delineating effects of boundary conditions as well as of aspect ratio of the plate.

Askari Farsangi, M. A.; Saidi, A. R.; Batra, R. C.

2013-10-01

67

Development of the nitride film thickness standard (NFTS)  

NASA Astrophysics Data System (ADS)

The semiconductor industry has been demanding film thickness reference material for films other than thermally grown silicon dioxide for sometime. To meet this challenge, Nitride Film Thickness Standard (NFTS) has been developed in four nominal thickness values, 20.0 nm, 90.0 nm, 120.0 nm and 200.0 nm. These are silicon nitride (Si3N4) films on silicon crystal substrate. Work is underway to develop a 9.0 nm standard. Thin nitride films are particularly needed for calibration of the thickness of nitride layers in capacitors and isolation masks for LOCOS (local oxidation of silicon). The reference material is certified for derived film thickness. The study consists of measurements made on four different sets of wafers that included patterned and unpatterned wafers. The measurements made on these wafer sets were used for answering issues related to film stability and cleaning. The stability study includes the search for a cleaning process that will restore a prior surface condition. On two sets of wafers two different types of cleaning procedures were used. Results indicate that a sulfuric acidmegasonic clean will etch the nitride film while an isopropyl alcohol clean followed by a deionized water rinse can be used over and over again. The third set of wafers was never cleaned and measurements were made on these over a period of two years. The last set of wafers is patterned. These are cleaned prior to measurement. Results show that LPCVD silicon nitride films are stable and can be used with confidence over a long period of time for calibrating optical metrology instruments.

Durgapal, Prabha

1998-07-01

68

Thickness-shear vibration of an elastic plate carrying an array of rigid microbeams with consideration of couple stresses  

Microsoft Academic Search

We study thickness-shear vibration of an elastic plate carrying an array of rigid microbeams with their bottoms attached to the top surface of the plate. The beams undergo rigid-body translation and rotation when the plate is in thickness-shear motion. The plate is modeled by the couple-stress theory of elasticity to properly take into account both the shear forces and the

Runyu Zhang; Jiemin Xie; Yuantai Hu; Jiashi Yang; Xuedong Chen

69

Fatigue strength evaluation of load-carrying cruciform fillet-welded joints made with mild steel plates of different thickness  

Microsoft Academic Search

This study examined the fatigue behavior of load-carrying cruciform fillet-welded joints made with mild steel plates of different thickness. Fatigue tests were carried out on four types of welded joint, made from two 6-, 9-, 14-, or 25-mm thick main plates and one 6- or 14-mm thick cross plate. The fatigue strength was also analyzed using linear elastic fracture mechanics

Shigenobu Kainuma; In-Tae Kim

2005-01-01

70

On the relations between cratonic lithosphere thickness, plate motions, and basal drag  

NASA Astrophysics Data System (ADS)

Seismic and thermal estimates suggest a highly variable thickness of Precambrian lithosphere (140-350 km), with a bimodal distribution for Archean cratons ( ~ 220 km and ~ 350 km). We discuss the origin of such large variations in lithospheric thickness and examine mechanisms of lithospheric erosion. Our analysis shows that the horizontal and vertical dimensions of Archean cratons are strongly correlated: larger cratons have thicker lithosphere. The basal drag model of lithosphere erosion (Sleep, 2001) is tested as a means of explaining the present-day bimodal distribution of lithospheric thicknesses of the Archean cratons. In agreement with theoretical predictions, we find that lithospheric thickness in Archean keels is proportional to the square root of the ratio of the craton length (along the direction of plate motion) to the plate velocity. These results show that the basal drag model provides a viable explanation for the variation in thickness of Archean cratonic roots. Basal drag may have varied in magnitude over the past 4 Ga. Higher mantle temperatures in the Archean would have resulted in lower mantle viscosity. This in turn would have reduced basal drag and basal erosion, and promoted the preservation of thick (>300 km) Archean keels, even if plate velocities were high during the Archean.

Artemieva, I.; Artemieva, I.; Mooney, W. D.

2001-12-01

71

On the relations between cratonic lithosphere thickness, plate motions, and basal drag  

USGS Publications Warehouse

An overview of seismic, thermal, and petrological evidence on the structure of Precambrian lithosphere suggests that its local maximum thickness is highly variable (140-350 km), with a bimodal distribution for Archean cratons (200-220 km and 300-350 km). We discuss the origin of such large differences in lithospheric thickness, and propose that the lithospheric base can have large depth variations over short distances. The topography of Bryce Canyon (western USA) is proposed as an inverted analog of the base of the lithosphere. The horizontal and vertical dimensions of Archean cratons are strongly correlated: larger cratons have thicker lithosphere. Analysis of the bimodal distribution of lithospheric thickness in Archean cratons shows that the "critical" surface area for cratons to have thick (>300 km) keels is >6-8 ?? 106 km2 . Extrapolation of the linear trend between Archean lithospheric thickness and cratonic area to zero area yields a thickness of 180 km. This implies that the reworking of Archean crust should be accompanied by thinning and reworking of the entire lithospheric column to a thickness of 180 km in accord with thickness estimates for Proterozoic lithosphere. Likewise, extrapolation of the same trend to the size equal to the total area of all Archean cratons implies that the lithospheric thickness of a hypothesized early Archean supercontinent could have been 350-450 km decreasing to 280-400 km for Gondwanaland. We evaluate the basal drag model as a possible mechanism that may thin the cratonic lithosphere. Inverse correlations are found between lithospheric thickness and (a) fractional subduction length and (b) the effective ridge length. In agreement with theoretical predictions, lithospheric thickness of Archean keels is proportional to the square root of the ratio of the craton length (along the direction of plate motion) to the plate velocity. Large cratons with thick keels and low plate velocities are less eroded by basal drag than small fast-moving cratons. Basal drag may have varied in magnitude over the past 4 Ga. Higher mantle temperatures in the Archean would have resulted in lower mantle viscosity. This in turn would have reduced basal drag and basal erosion, and promoted the preservation of thick (>300 km) Archean keels, even if plate velocities were high during the Archean. ?? 2002 Elsevier Science B.V. All rights reserved.

Artemieva, I. M.; Mooney, W. D.

2002-01-01

72

Measuring thickness change of transparent plate by electronic speckle pattern interferometry and digital image correlation  

NASA Astrophysics Data System (ADS)

The thickness change of transparent plates was measured by electronic speckle pattern interferometry (ESPI) method and digital image correlation (DIC) method. An out-of-plane ESPI system was developed based on the Michelson interferometer, and a new thickness measurement method was designed, which is on the basis of Snell's law of refraction and DIC. The main principles and experimental procedures of these two methods were presented. The thickness change of polymethyl specimens under uniaxial tensile loading were measured by the optical techniques and compared with each other. The results reveal that the data obtained with DIC method achieve better linearity than ESPI.

Dai, Xiangjun; Yun, Hai; Pu, Qi

2010-09-01

73

Penetration of a Rigid Rod into a Thick Steel Plate at Elevated Velocities  

Microsoft Academic Search

Results of studies on the effect of impact velocities and shapes of the head face of a rigid rod on its behavior upon penetration into a thick plate from mild low-carbon steel at velocities of up to 600 m\\/s are presented. Experimental relations between penetration depths and impact velocities were obtained for rods with conical and hemispherical head faces. A

V. K. Golubev; V. A. Medvedkin

2001-01-01

74

BENDING AND FORCED VIBRATION RESPONSE OF A CLAMPED ORTHOTROPIC THICK PLATE AND SANDWICH PANEL  

Microsoft Academic Search

A closed-form solution for the forced response of an orthotropic thick plate and sandwich panel has been developed and is presented in this paper. The paper outlines the methodology and develops the formulation to enable the solution to be derived. A novel truss-core sandwich panel is introduced and a method is outlined in which the panel is represented as an

T. S. LOK; Q. H. CHENG

2001-01-01

75

Bending and Forced Vibration Response of a Clamped Orthotropic Thick Plate and Sandwich Panel  

Microsoft Academic Search

A closed-form solution for the forced response of an orthotropic thick plate and sandwich panel has been developed and is presented in this paper. The paper outlines the methodology and develops the formulation to enable the solution to be derived. A novel truss-core sandwich panel is introduced and a method is outlined in which the panel is represented as an

T. S. Lok; Q. H. Cheng

2001-01-01

76

Large deformation analysis of moderately thick laminated plates on nonlinear elastic foundations by DQM  

Microsoft Academic Search

In this paper, the nonlinear behavior of symmetric and antisymmetric cross ply, thin to moderately thick, elastic rectangular laminated plates resting on nonlinear elastic foundations are studied using differential quadrature method (DQM). The first-order shear deformation theory (FSDT) in conjunction with the Green’s strain and von Karman hypothesis are assumed for modeling the nonlinear behavior. Elastic foundation is modeled as

P. Malekzadeh; A. R. Setoodeh

2007-01-01

77

Effect of target thickness in blunt projectile penetration of Weldox 460 E steel plates  

Microsoft Academic Search

This paper describes an experimental, analytical and numerical investigation of the penetration and perforation of circular Weldox 460 E steel plates with different thicknesses struck by a blunt projectile at various impact velocities. In the experimental tests, a compressed gas gun was used to launch the sabot mounted projectile at impact velocities well above and just below the ballistic limit

Tore Børvik; Odd Sture Hopperstad; Magnus Langseth; Kjell Arne Malo

2003-01-01

78

Optimal electrode shape and size of doubly rotated quartz plate thickness mode piezoelectric resonators  

Microsoft Academic Search

Using the Stevens-Tiersten equation for slowly varying thickness modes in doubly rotated quartz plate piezoelectric resonators, we determine optimal electrode shape and size for these resonators. The electrodes obtained are optimal in that they satisfy Bechmann's number in every direction.

Zengtao Yang; Jiashi Yang; Yuantai Hu

2008-01-01

79

A phenomenological model for perforation of moderately thick plates by tumbling projectiles  

Microsoft Academic Search

A phenomenological model has been developed to describe the mechanism of tumbling perforation of blunt-faced cylindrical projectiles in moderately thick aluminum plates. The perforation process, based on experimental observations, consists of four stages: erosion; plugging; hole enlargement and petaling. The modeling in the plugging stage consists sequentially of cratering, plug formation, plug separation, plug slipping and post perforation deformation. Bulging

Kezhun Li; Werner Goldsmith

1996-01-01

80

Effect of Ni Plating Thickness on Fatigue Failure of Lead-free Solder Joints  

Microsoft Academic Search

The purpose of this paper is to study the effect of plating thickness on fatigue failure of lead-free solder joints after thermal aging. Cyclic three-point bending tests were carried out and investigate the relationships between intermetallic compound (IMC) layer development and the fatigue life of solder joints. After the fatigue tests, cross- sections of solder joint were observed by scanning

M. Omiya; Takeshi Miyazaki; Hirotsugu Inoue; K. Kishimoto; M. Amagai

2006-01-01

81

Aluminum-Copper-Lithium Alloy 2050 Developed for Medium to Thick Plate  

NASA Astrophysics Data System (ADS)

This article discusses Al-Cu-Li 2050 alloy developed, qualified, and produced by Alcan Aerospace as plates. AA2050 alloy offers a low density high corrosion resistant alternative to incumbent medium to thick plate alloys like 7050-T7451, and to thin plate alloys like 2024 or higher damage tolerant versions. The fundamentals behind the choice of the Al-Cu-Li chemistry are highlighted, as well as the property balance generated in a wide range of thickness from 12 to 127 mm (0.5 to 5 in.). Manufacturing behavior of the alloy when machining or friction stir welding is also discussed in detail. Finally, it is shown that the appropriate recycling investments and logistics permit the use of 2050 alloy at an acceptable level of extra cost per kilo saved, when weight benefits are taken into account.

Lequeu, Ph.; Smith, K. P.; Daniélou, A.

2010-08-01

82

Active sound radiation control of a thick piezolaminated smart rectangular plate  

NASA Astrophysics Data System (ADS)

A spatial state-space formulation based on the linear three-dimensional piezoelasticity theory in conjunction with the classical Rayleigh integral acoustic radiation model is employed to obtain a semi-analytic solution for the coupled vibroacoustic response of a simply supported, arbitrarily thick, piezolaminated rectangular plate, set in an infinite rigid baffle. The smart structure is composed of an orthotropic supporting core layer integrated with matched volume velocity spatially distributed piezoelectric sensor and uniform force actuator layers. To assist controller design, a frequency-domain subspace-based identification technique is applied to estimate the coupled fluid–structure dynamics of the system. A standard linear quadratic Gaussian (LQG) optimal controller is subsequently synthesized and simulated based on the identified model and the optimal control input voltage for minimizing the estimated net volume velocity (total radiated power) of the panel is calculated in both frequency and time domains. Numerical simulations demonstrate the effectiveness of the adopted volumetric sensing/actuation technique in conjunction with the optimal control strategy for suppressing the predicted sound radiation response of a three-layered (NaNb5O15/Al/PZT4) sandwich panel in both frequency and time domains. The trade-off between dynamic performance and control effort penalty is examined for two different types of loading (i.e., impulsive and broadband random disturbances). Validity of the results is demonstrated by comparison with a commercial finite element package, as well as with the data available in the literature.

Hasheminejad, Seyyed M.; Keshavarzpour, Hemad

2013-09-01

83

An equivalent single-layer approach for free vibration analysis of smart laminated thick composite plates  

NASA Astrophysics Data System (ADS)

An equivalent single-layer model for the free vibration analysis of smart laminated plates is presented. The electric and magnetic fields are assumed to be quasi-static, and third order in-plane kinematics is employed to adequately take the shear influence into account when the plate thickness increases. The model governing equations are the plate equations of motion written in terms of mechanical primary variables and effective stiffness coefficients, which take the multi-field coupling effects into account. The model shows that the surface magneto-electric boundary conditions enter the definitions of the laminate forces and moment resultants. Moreover, it reveals that new stiffness terms, which are related to the derivatives of the transverse displacement component and are exclusively associated with the piezoelectric and piezomagnetic couplings, are involved. Free vibration solutions for simply supported plates are presented to validate the model by comparing the present results with benchmark 3D solutions. Comparison of the results obtained by lower order models, namely zero and first order shear deformation theories, is presented and discussed, focusing on the adequateness of the obtained models with respect to the plate thickness. Some characteristic features of smart laminate behavior have also been addressed.

Milazzo, A.; Orlando, C.

2012-07-01

84

Estimation of Impact Load in Thick Plate by Using Theoretical Green Function and Experimental Measurement of Vibration  

Microsoft Academic Search

The classic plate theory (CPT) as a theoretical solution to an impact load has been used in a thin plate. However, The CPT is not any more useful solution for the impact load in the industrial power plant, which is generally constructed by the thick plate. In this paper a novel and effective approach is developed to determine the time

H. W. Kim; S. K. Lee

2008-01-01

85

Vibrodiagnostic parameters of fatigue damage in rectangular plates. Part 3. Through-the-thickness and surface semi-elliptical cracks  

Microsoft Academic Search

The paper addresses the analytical determination of vibrodiagnostic parameters that describe the presence of normal-rupture\\u000a flat through-the-thickness and surface semi-elliptical central cracks in a rectangular homogeneous plate of constant thickness\\u000a for various plate fixing conditions and vibration modes. It is shown that the most sensitive vibrodiagnostic damage parameter\\u000a of a plate is the variation of the logarithmic decrement in the

V. V. Matveev; O. E. Boginich

2006-01-01

86

The stress and strain concentrations of an elliptical hole in an elastic plate of finite thickness subjected to tensile stress  

Microsoft Academic Search

The elastic stress and strain fields in a plate of finite thickness containing an elliptical hole are systematically investigated\\u000a using the 3D finite element method. It is found that the stress and strain concentrations are different in the plate of finite\\u000a thickness even if the plate is in an elastic state. The relation between the stress and the strain concentration

Zheng Yang

2009-01-01

87

Non-destructive thickness measurement of dichromated gelatin films deposited on glass plates  

NASA Astrophysics Data System (ADS)

A quick estimation of the thickness of thin films deposited on glass plates is described in this paper. The principle of the method is based on the measurement of the Haidinger fringes generated by the film. For ease of observation and measurement, a commercial Fizeau-type interferometer such as a Zygo interferometer using a large angle of illumination has been used. The simple modification to observe the Haidinger fringes with the Fizeau-type interferometer is also described. The thickness of the film is related to the diameters of the Haidinger fringes. It is possible to estimate the thickness quickly by counting the number of fringes. A more accurate estimate can be obtained by the measurement of the diameters of the fringes and using these data in a formula that relates these two to the thickness of the film. The method is found to be useful for measuring the thickness of dichromated gelatin films (DCG) coated on a substrate to make holographic optical elements. The accuracy in estimating the thickness of the film is of the order ±1?m. The method is entirely non-destructive and works well in the thickness range of 5 150?m.

Shukla, R. P.; Udupa, D. V.; Das, N. C.; Mantravadi, Murty V.

2006-10-01

88

Accurate free vibration analysis of thick laminated circular plates with attached rigid core  

NASA Astrophysics Data System (ADS)

This paper deals with the free vibration behavior of laminated transversely isotropic circular plates with axisymmetric rigid core attached at the center. The governing equations of motion are obtained based on Mindlin's first-order shear deformation plate theory. Two possible categories of vibration modes related to up-down translation of the core and wobbly rotation of the core about a diameter are studied. Accurate natural frequencies hitherto not reported in the literature are presented for a wide range of thickness-to-radius ratio, inner-to-outer radius ratio, mass and moment of inertia ratios of the core and various boundary conditions at the outer edge of the plate. Numerical results are compared with those of a three-dimensional finite element method (3-D FEM) to demonstrate the high accuracy and reliability of the current analysis.

Hosseini-Hashemi, Sh.; Rezaee, V.; Atashipour, S. R.; Girhammar, U. A.

2012-12-01

89

A Study on Segmented Multiple-Step Forming of Doubly Curved Thick Plate by Reconfigurable Multi-Punch Dies  

SciTech Connect

Doubly curved thick plate forming in shipbuilding industries is currently performed by a thermal forming process, called as Line Heating by using gas flame torches. Due to the empirical manual work of it, the industries are eager for an alternative way to manufacture curved thick plates for ships. It was envisaged in this study to manufacture doubly curved thick plates by the multi-punch die forming. Experiments and finite element analyses were conducted to evaluate the feasibility of the reconfigurable discrete die forming to the thick plates. Single and segmented multiple step forming procedures were considered from both forming efficiency and accuracy. Configuration of the multi-punch dies suitable for the segmented multiple step forming was also explored. As a result, Segmented multiple step forming with matched dies had a limited formability when the objective shapes become complicate, while a unmatched die configuration provided better possibility to manufacture large curved plates for ships.

Ko, Young Ho; Han, Myoung Soo; Han, Jong Man [Daewoo Shipbuilding and Marine Engineering Co., Ltd., 1, Aju-dong, Geoje, Gyeongnam, 656-714 (Korea, Republic of)

2007-05-17

90

Analysis of thick plates by using a higher-order shear and normal deformable plate theory and MLPG method with radial basis functions  

Microsoft Academic Search

Infinitesimal deformations of a homogeneous and isotropic thick elastic plate have been analyzed by using a meshless local Petrov–Galerkin (MLPG) method and a higher-order shear and normal deformable plate theory (HONSDPT). Radial basis functions (RBF) are employed for constructing trial solutions, while a spline function is used as the weight function over a local subdomain. The present method uses a

J. R. Xiao; R. C. Batra; D. F. Gilhooley; J. W. Gillespie Jr; M. A. McCarthy

2007-01-01

91

Exact solutions for free flexural vibration of Lévy-type rectangular thick plates via third-order shear deformation plate theory  

Microsoft Academic Search

In this paper, exact closed-form solutions in explicit forms are presented for transverse vibration analysis of rectangular thick plates having two opposite edges hard simply supported (i.e., Lévy-type rectangular plates) based on the Reddy’s third-order shear deformation plate theory. Two other edges may be restrained by different combinations of free, soft simply supported, hard simply supported or clamped boundary conditions.

Shahrokh Hosseini-Hashemi; Mohammad Fadaee; Hossein Rokni Damavandi Taher

2011-01-01

92

Stress analysis of a thick fibre-reinforced plastic laminated square plate containing two elliptical holes under transverse uniform loading  

Microsoft Academic Search

A displacement-based finite element analysis applicable for thick laminated composite plate is described. An isoparametric quadratic quadrilateral element with eleven degrees of freedom per node is used in this analysis. The finite element formulation is then used for the analysis of stresses of a simply supported finite laminated square plate containing two elliptical holes under transverse uniform loading. The results

T. K. Paul; K. M. Rao

1992-01-01

93

Ultrasound radiation into water by a Lamb wave device using a piezoelectric ceramic plate with spatially varying thickness  

Microsoft Academic Search

The operation of a Lamb wave device, using an interdigital transducer and a piezoelectric ceramic plate with spatially varying thickness, is investigated both theoretically and experimentally to understand the characteristics of ultrasound radiation into water that accompanies Lamb wave propagation. A new calculation model for Lamb wave propagation in a water-loaded inhomogeneous plate is established and the Lamb wave velocities

Kenji Motegi

1999-01-01

94

Variable thickness double-refracting plate. [for modulating light source for isotope-shift Zeeman-effect atomic absorption spectrometer  

Microsoft Academic Search

This invention provides an A.C., cyclic, current-controlled, phase retardation plate that uses a magnetic clamp to produce stress birefringence. It was developed for an Isotope-Zeeman Atomic Absorption Spectrometer that uses polarization modulation to effect automatic background correction in atomic absorption trace-element measurements. To this end, the phase retardation plate of the invention is a variable thickness, photoelastic, double-refracting plate that

Hadeishi

1976-01-01

95

Three-dimensional free vibration of thick functionally graded annular plates in thermal environment  

NASA Astrophysics Data System (ADS)

The free vibration analysis of functionally graded (FG) thick annular plates subjected to thermal environment is studied based on the 3D elasticity theory. The material properties are assumed to be temperature dependent and graded in the thickness direction. Considering the thermal environment effects and using Hamilton's principle, the equations of motion are derived. The effects of the initial thermal stresses are considered accurately by obtaining them from the 3D thermoelastic equilibrium equations. The differential quadrature method (DQM) as an efficient and accurate numerical tool is used to solve both the thermoelastic equilibrium and free vibration equations. Very fast rate of convergence of the method is demonstrated. Also, the formulation is validated by comparing the results with those obtained based on the first-order shear deformation theory and also with those available in the literature for the limit cases, i.e. annular plates without thermal effects. The effects of temperature rise, material and geometrical parameters on the natural frequencies are investigated. The new results can be used as benchmark solutions for future researches.

Malekzadeh, P.; Shahpari, S. A.; Ziaee, H. R.

2010-02-01

96

Stress analysis of a thick fibre-reinforced plastic laminated square plate containing two elliptical holes under transverse uniform loading  

NASA Astrophysics Data System (ADS)

A displacement-based finite element analysis applicable for thick laminated composite plate is described. An isoparametric quadratic quadrilateral element with eleven degrees of freedom per node is used in this analysis. The finite element formulation is then used for the analysis of stresses of a simply supported finite laminated square plate containing two elliptical holes under transverse uniform loading. The results are compared with the exact elasticity solutions, which demonstrate the validity of the method. The variation of the stress concentration factor due to the change of the distance between the holes, the hole size and the plate thickness is presented in graphical form and discussed.

Paul, T. K.; Rao, K. M.

1992-04-01

97

The influence of Poisson’s ratio on thickness-dependent stress concentration at elliptic holes in elastic plates  

Microsoft Academic Search

The influence of Poisson’s ratio (?) on the thickness-dependent stress concentration factor (SCF) along the root of elliptic holes in elastic plates subjected to tension is systematically investigated by use of three-dimensional finite element method. It is found that the thickness-dependent maximum of SCF, (Kt)max, increases significantly with increasing ?. As the thickness to root radius ratio B\\/? grows from

Peishi Yu; Wanlin Guo; Chongmin She; Junhua Zhao

2008-01-01

98

Estimation of Impact Load in Thick Plate by Using Theoretical Green Function and Experimental Measurement of Vibration  

NASA Astrophysics Data System (ADS)

The classic plate theory (CPT) as a theoretical solution to an impact load has been used in a thin plate. However, The CPT is not any more useful solution for the impact load in the industrial power plant, which is generally constructed by the thick plate. In this paper a novel and effective approach is developed to determine the time history of the impact load on a thick aluminum plate based on the analysis of the acoustic waveforms measured by a sensor array located on the thick plate surface in combination with the theoretical Green's function for the plate. The Green's functions are derived based on either the exact elastodynamic or theory the approximate shear deformation plate theory (SDPT). If the displacement is measured on the plate, then the time history of impact load can be calculated by deconvolving the measured displacement with the theoretical Green's function. The reconstructed time history for impact load is compared with the time history of the impact load measured by the force transducer. A good prediction is found. This technique presents a valuable method for identification of source and may be applied to in-service structures under impact to signals recorded from acoustic emission of propagating cracks.

Kim, H. W.; Lee, S. K.

99

Elastostatic Deformations of a Thick Plate by using a Higher-Order Shear and Normal Deformable Plate Theory and two Meshless Local Petrov-Galerkin (MLPG) Methods  

Microsoft Academic Search

We use two meshless local Petrov-Galerkin formulations, namely, the MLPG1 and the MLPG5, to analyze infinitesimal deformations of a homogeneous and isotropic thick elastic plate with a higher-order shear and normal deformable plate theory. It is found that the two MLPG formulations give results very close to those obtained by other researchers and also by the three- dimensional analysis of

L. F. Qianl; R. C. Batra; L. M. Chen

100

Industrial standard for calculating the reinforcement of holes in shells, cross-overs, and bottom-plates  

Microsoft Academic Search

the Leningrad Branch of the All-Union Scientific-Resea rch and Design Institute for Chemical Engineering in collaboration with the All-Union Scientific-Resea rch Institute for Chemical Engineering. The standard applies to the calculation of the reinforcement of holes in shells, cross-overs, and bottom-plates of vessels and apparatus, for Ds _< 4000 cm 2 {where D, s are inner diameter and thickness, respectively,

A. V. Gornostaev; Yu. P. Simonov; V. F. Kurylev; V. I. Rachkov; V. A. Freitag

1975-01-01

101

An analysis of thickness-shear vibrations of doubly-rotated quartz crystal plates with the corrected first-order mindlin plate equations.  

PubMed

The Mindlin plate equations have been widely used in the analysis of high-frequency vibrations of quartz crystal resonators with accurate solutions, as demonstrated by the design procedure based on analytical results in terms of frequency, mode shapes, and optimal parameters for the ATcut quartz crystal plate, which is the core element in a resonator structure. Earlier studies have been focused on the AT-cut (which is one type of rotated Y-cut) quartz crystal plates because it is widely produced and has relatively simple couplings of vibration modes at thickness-shear frequencies of the fundamental and overtone modes. The simplified equations through the truncation, correction, and modification of the Mindlin plate equations have been widely accepted for practical applications, and further efforts to expand their applications to similar problems of other material types, such as doubly-rotated quartz crystals, with the SC-cut being a typical and popular one, are also naturally expected. We have found out that the Mindlin plate theory can be truncated and corrected for the SC-cut quartz crystal plates in a manner similar to the AT-cut plates. The analytical results show that the corrected Mindlin plate equations are equally accurate and convenient for obtaining essential design parameters of resonators for the thicknessshear vibrations of SC-cut quartz crystal plates. PMID:24158292

2013-11-01

102

3C-5 The Analysis of Thickness-Shear Vibrations of the Third-Order Overtone Mode of Quartz Crystal Plates with Mindlin Plate Theory  

Microsoft Academic Search

Extensive efforts have been made on the analysis of quartz crystal resonators vibrating at the fundamental thickness-shear mode, but demands for overtone products with higher frequencies are calling for the study of vibrations of higher-order thickness-shear modes. The challenges of such research are multifold, including demands of appropriate equations to describe the vibrations of overtone modes of piezoelectric plates as

Ji Wang; Rongxing Wu; Jianke Du; Jiaming Xu; Dejin Huang; Min-Chiang Chao

2007-01-01

103

Effects of a liquid layer on thickness-shear vibrations of rectangular AT-cut quartz plates.  

PubMed

Thickness-shear vibrations of a rectangular AT-cut quartz with one face in contact with a layer of Newtonian (linearly viscous and compressible) fluid are studied. The two-dimensional (2-D) governing equations for vibrations of piezoelectric crystal plates given previously are used in the present study. The solutions for 1-D shear wave and compressional wave in a liquid layer are obtained, and the stresses at the bottom of the liquid layer are used as approximations to the stresses exerting on the crystal surface in the plate equations. Closed form solutions are obtained for both free and piezoelectrically forced thickness-shear vibrations of a finite, rectangular AT-cut quartz in contact with a liquid layer of finite thickness. From the present solutions, a simple and explicit formula is deduced for the resonance frequency of the fundamental thickness-shear mode, which includes the effects of both shear and compressional waves in the liquid layer and the effect of the thickness-to-length ratio of the crystal plate. The formula reduces to the widely used frequency equation obtained by many previous investigators for infinite plates. The resonance frequency of a rectangular AT-cut quartz, computed as a function of the thickness of the adjacent liquid layer, agrees closely with the experimental data measured by Schneider and Martin. PMID:12046936

Lee, Peter C Y; Huang, Rui

2002-05-01

104

Crustal Thickness Variations Along the Southeastern Caribbean Plate Boundary From Teleseismic and Active Source Seismic Data  

NASA Astrophysics Data System (ADS)

Insight into the topography of the Moho discontinuity beneath Venezuela has been progressively gained since the 1990's through seismic refraction studies carried out in the south and east of the country. More recently, both active and passive, land and marine seismic data were acquired by the U.S. BOLIVAR and Venezuelan GEODINOS projects to understand accretion processes and mechanisms for continental growth. The passive component includes an 18-month deployment of 27 PASSCAL broadband seismographs, a 12-month deployment of 15 OBSIP broadband instruments and an ongoing deployment of 8 Rice broadband seismometers. Additionally, data from the 34 BB stations of the national seismic network of Venezuela and the GSN SDV station, give a seismic dataset from 84 stations covering an area of ~750,000 km2. The active component includes 4 onshore-offshore refraction/wide angle reflection profiles as well as the recording of airgun blasts from offshore seismic lines by BB stations in mainland Venezuela and the Leeward Antilles. This abundance of datasets allows us to estimate Moho depths using different methods such as receiver functions, and forward and inverse modeling of wide-angle datasets, but also poses the challenge of reconciling the different values obtained to achieve robust results. Generally the active source and receiver function estimates are close to one another. We present a composite crustal thickness map showing a highly variable crustal thicknesses ranging from 15 km beneath the Caribbean LIP, to ~55 km beneath eastern Venezuela. Crustal thickness is strongly correlated with geologic terranes, but not always as expected. The thickest crust is found to exist in the east of the country, beneath the sedimentary basins north of the Orinoco River where depth to Moho exceeds 50 km. Crustal thickness beneath most of the Precambrian Guayana Shield is fairly constant at ~38 km . In contrast, we observe relatively thin (~25-30 km) crust in the eastern and western coastal mountains, suggesting a significant portion of the high topography of the costal mountain ranges has a dynamic origin. Crustal thickness changes of more than 10km are observed crossing the coast in the plate boundary zone, but are not always directly associated with the surface expression of the strike-slip fault system.

Bezada, M. J.; Niu, F.; Baldwin, T. K.; Pavlis, G.; Vernon, F.; Rendón, H.; Zelt, C. A.; Schmitz, M.; Levander, A.

2006-12-01

105

Submicrometre scale single-crystalline gold plates of nanometre thickness: synthesis through a nucleobase process and growth mechanism  

Microsoft Academic Search

Synthesis of submicrometre scale single-crystalline gold plates of nanometre thickness in the presence of nucleobase guanine through chemical reduction of HAuCl4 was investigated. The elemental composition of the as-prepared gold nanoplates was estimated using energy-dispersive x-ray spectroscopy. The as-prepared gold plates were composed of essentially (111) lattice planes, as revealed by both x-ray diffraction (XRD) and transmission electron microscopy (TEM)

Hui Wei; Erkang Wang

2007-01-01

106

A semi-analytical DQEM for free vibration analysis of thick plates with two opposite edges simply supported  

Microsoft Academic Search

This paper is introducing a semi-analytical differential quadrature element method (DQEM) based on first-order shear deformation theory for free vibration analysis of thick plates. By decomposing the plate into a series of sub-domains or elements, any discontinuity in geometry, material properties, and elastic foundations in one direction can be handled conveniently. Classical, as well as non-classical boundary conditions can be

P. Malekzadeh; G. Karami; M. Farid

2004-01-01

107

Deep Dry Etching of Quartz Plate Over 100 mum in Depth Employing Ultra-Thick Photoresist (SU8)  

Microsoft Academic Search

The newly developed backside exposure method enabled us to easily fabricate a vertical\\/high aspect ratio ultra-thick photoresist (SU-8) pattern on a quartz plate. Deep quartz plate etching masked with SU-8 resist was studied employing an ICP etcher with a C4F8\\/H2\\/Ar gas mixture. Two issues took place in the long time etching. One was a corn-like defect generated on the quartz

Takayuki Fukasawa; Yasuhiro Horiike

2003-01-01

108

Three-dimensional constraint effects on stress intensity distributions in plate geometries with through-thickness cracks  

NASA Astrophysics Data System (ADS)

Results are presented of a finite element analyses of 3D crack tip loading situations in geometrically 2D geometries with through-thickness cracks. The results show that the local constraint variation toward the crack tip causes an increase in stress intensity, the fact which is usually neglected in analyses which assume a constant stress state throughout the geometry. Crack tip tunneling causes a redistribution of stress intensity across the thickness, with an almost constant stress intensity being found for a relative tunnel depth of about 2.5 percent of the plate thickness, for a geometry that is predominantly in plane stress. Shear lips are shown to reduce the mean equivalent stress intensity by a factor equal to the square root of the ratio between the plate thickness and the projected length of the crack front.

Bakker, A.

1992-11-01

109

78 FR 63017 - Exhaust Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate for...  

Federal Register 2010, 2011, 2012, 2013

...Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate for Aircraft...comments amending the emission standards for turbine engine powered airplanes to incorporate...The EPA also proposed adopting the gas turbine engine test procedures of the...

2013-10-23

110

78 FR 63015 - Exhaust Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate for...  

Federal Register 2010, 2011, 2012, 2013

...Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate for Aircraft...amended the emission standards for certain turbine engine powered airplanes to incorporate...The EPA also proposed adopting the gas turbine engine test procedures of the...

2013-10-23

111

Enumeration of heterotrophs, fecal coliforms and Escherichia coli in water: comparison of 3M™ Petrifilm™ plates with standard plating procedures  

Microsoft Academic Search

A total of 177 naturally contaminated water samples were analyzed by membrane filtration according to the Standard Methods for the Examination of Water and Wastewater published by the American Public Health Association. Filters were incubated in parallel on mHPC-agar and 3M™ Petrifilm™ Aerobic Count Plates (Petrifilm™ AC plates) for heterotrophic counts. Fecal coliforms and Escherichia coli were enumerated on mFC-agar

H. Schraft; L. A. Watterworth

2005-01-01

112

Optical thickness measurement of mask blank glass plate by the excess fraction method using a wavelength-tuning interferometer  

NASA Astrophysics Data System (ADS)

The absolute optical thickness of a 140-mm2 mask blank glass plate 3.1 mm thickness was measured by three-surface interferometry using a wavelength-tuning Fizeau interferometer. The interference order was determined by the excess fraction method. The wavelength of a tunable laser diode was scanned linearly from 632 to 642 nm, and a CCD detector recorded 2000 interference images. Two kinds of optical thicknesses measured by discrete Fourier analysis and phase-shifting were synthesized to obtain the optical thickness with respect to the ordinary refractive index. The optical thickness defined by the group refractive index at the 637 nm central wavelength was measured by wavelength scanning. The optical thickness deviation defined by the ordinary refractive index was measured using tunable phase-shifting. The systematic errors caused by nonlinearity in the wavelength tuning were corrected through correlation analysis between the theoretical and observed interference fringes.

Kim, Yangjin; Hibino, Kenichi; Sugita, Naohiko; Mitsuishi, Mamoru

2013-10-01

113

Linear and nonlinear analyses of thick composite circular plates using the finite element method  

Microsoft Academic Search

A new finite element for circular plates based on Mindlin's shear deformable plate theory is developed. Unlike conventional plate elements, these new elements may be stacked on top of one another to model laminated plates. The elements assure continuity of the displacements between the layers, but not continuity of the traction vectors. The element does not account for interlaminar slip

George Henry Thiel

1991-01-01

114

Axisymmetric bending analysis of thick functionally graded circular plates using fourth-order shear deformation theory  

Microsoft Academic Search

In the present article, axisymmetric bending and stretching of functionally graded (FG) circular plates subjected to uniform transverse loading based on fourth-order shear deformation plate theory (FOST) have been studied. Using a fourth-order shear deformation theory, the solutions for deflection and rotation functions of FG plates are presented in terms of the corresponding quantities for a homogeneous plate using the

S. Sahraee; A. R. Saidi

2009-01-01

115

Laser-Assisted Stir Welding of 25-mm-Thick HSLA-65 Plate  

NASA Astrophysics Data System (ADS)

Laser-assisted stir welding is a hybrid process that combines energy from a laser with functional heating and mechanical energy to join materials in the solid state. The technology is an adaptation of friction stir welding which is particularly suited for joining thick plates. Aluminum plates up to 75 mm thick have been successfully joined using friction stir welding. Since joining occurs in the solid state, stir technology offers the capability for fabricating full penetration joints in thick plates with better mechanical properties and less weld distortion than is possible by fusion processes. Currently friction stir welding is being used in several industries to improve productivity, reduce weight, and increase the strength of welded structures. Examples include: (a) the aircraft/aerospace industry where stir technology is currently being used to fabricate the space shuttle's external tank as well as components of the Delta family of rockets; (b) the shipping industry where container manufacturers are using stir technology to produce lighter containers with more payload capacity; and (c) the oil industry where offshore platform manufactures are using automated stir welding plants to fabricate large panels and structures up to 16 meters long with widths as required. In all these cases, stir technology has been restricted to aluminum alloys; however, stainless and HSLA 65 steels have been recently stir welded with friction as the primary heat source. One of the difficulties in adapting stir welding to steel is tool wear aggravated by the high tool rubbing velocities needed to provide frictional heat input into the material. Early work showed that the tool shoulder reached temperatures above 1000 C and the weld seam behind the tool stayed within this temperature range for up to 25 mm behind the tool. Cross sections of stir welded samples showed that the heat-affected zone is relatively wide and follows the profile of the tool shoulder. Besides minimizing the tool wear by increasing the energy into the material, another benefit of the proposed Laser Assisted Stir Welding (LASW is to reduce the width of the heat affected zone which typically has the lowest hardness in the weld region. Additionally, thermal modeling of the friction stir process shows that the heat input is asymmetric and suggests that the degree of asymmetry could improve the efficiency of the process. These asymmetries occur because the leading edge of the tool supplies heat to cold material while the trailing edge provides heat to material already preheated by the leading edge. As a result, flow stresses on the advancing side of the joint are lower than corresponding values on the retreating side. The proposed LASW process enhances these asymmetries by providing directional heating to increase the differential in flow stress across the joint and improve the stir tool efficiency. Theoretically the LASW process can provide the energy input to allow the flow stresses on the advancing side to approach zero and the stir efficiency to approach 100 percent. Reducing the flow stresses on the advancing side of the weld creates the greatest pressure differential across the stir weld and eliminates the possibility of voids on the advancing side of the joint. Small pressure differentials result in poor stir welds because voids on the advancing side are not filled by the plastic flow of material from the retreating side.

Williamson, Keith M.

2002-12-01

116

FUNDAMENTAL AREAS OF PHENOMENOLOGY (INCLUDING APPLICATIONS): Effects of Thickness Deviation of Elastic Plates in Multi-Layered Resonance Systems on Frequency Spectra  

NASA Astrophysics Data System (ADS)

A model of high-overtone bulk acoustic resonators is used to study the effects of thickness deviation of elastic plates on resonance frequency spectra in planar multi-layered systems. The resonance frequency shifts induced by the thickness deviations of the elastic plates periodically vary with the resonance order, which depends on the acoustic impedance ratios of the elastic plates to piezoelectric patches. Additionally, the center lines of the frequency shift oscillations linearly change with the orders of the resonance modes, and their slopes are sensitive to the thickness deviations of the plates, which can be used to quantitatively evaluate the thickness deviations.

Zhang, Hui; Zhang, Shu-Yi; Fan, Li

2009-08-01

117

Comparison of the stress intensity factor of T and cruciform welded joints with different main and attachment plate thickness  

Microsoft Academic Search

The present study compares the stress intensity factor of T and cruciform welded joints containing Lack of Penetration defects and gives new results in the form of parametric equation coefficients for the T joint case. Cruciform and T welded joints with equal and unequal attachment and main plate thickness have been analysed by the finite element method. For the T

A. Khodadad Motarjemi; A. H. Kokabi; A. A. Ziaie; S. Manteghi; F. M. Burdekin

2000-01-01

118

Simultaneous measurement of distance and thickness of a thin metal plate with an electromagnetic sensor using a simplified model  

Microsoft Academic Search

This paper presents a simplified model which can de- scribe the inductance change when an air-core coil is placed next to a thin nonmagnetic metallic plate. The model has two indepen- dent parameters and is valid for a range of thickness, conductivity, and lift-offs. Use of this new relationship provides a fast and ac- curate method to measure the distance

Wuliang Yin; Anthony J. Peyton; Stephen J. Dickinson

2004-01-01

119

Effects of Humidity on the Fatigue Crack Growth Rate in Aluminum Alloy 8090-T8771 Thick Plate.  

National Technical Information Service (NTIS)

The purpose of this investigation was to determine the effect of relative humidity on the fatigue crack growth rate in aluminum alloy 8090 thick plate thermomechanically processed to the T8771 condition. High and low humidity fatigue crack growth rate dat...

R. R. Cervay K. V. Jata

1995-01-01

120

Perforation of 12 mm thick steel plates by 20 mm diameter projectiles with flat, hemispherical and conical noses  

Microsoft Academic Search

Projectiles with three different nose shapes (blunt, hemispherical and conical) have been used in gas gun experiments to penetrate 12mm thick Weldox 460E steel plates. Based on the experimental results, the residual velocity curves of the target material were constructed and compared. It was found that the nose shape of the projectile significantly affected both the energy absorption mechanism and

T Børvik; M Langseth; O. S Hopperstad; K. A Malo

2002-01-01

121

Postirradiation Dynamic Tear and Charpy-V Performance of 12-in. Thick A533-B Steel Plates and Weld Metal.  

National Technical Information Service (NTIS)

Charpy-V (C sub V) and dynamic tear (DT) test comparisons are developed for the irradiated condition of two 12 in. thick A533-B steel plates and a submerged arc weld deposit. Materials for the investigation were donated by the U.S. Atomic Energy Commissio...

J. R. Hawthorne

1971-01-01

122

Effect of Welding Atmosphere at Bottom Surface on Welding Phenomenan in Full Penetration Laser Welding of Thick Plate  

Microsoft Academic Search

The keyhole behaviour and bubble formation were investigated in the full penetration laser welding of 11 and 15 mm thick plate with various kinds of atmosphere at the bottom side. Prevention of some defects was also attempted. Back surface atmosphere was controlled using a shielding box fixed on the sample back surface to avoid contamination from the air and also

Goro Arakane; Susumu Tsukamoto; Hiroshi Honda; Seiji Kuroda; Takeshi Fukushima

2007-01-01

123

An analysis for the elasto-plastic problem of the moderately thick plate using the meshless local Petrov–Galerkin method  

Microsoft Academic Search

A meshless local Petrov–Galerkin method for the analysis of the elasto-plastic problem of the moderately thick plate is presented. The discretized system equations of the moderately thick plate are obtained using a locally weighted residual method. It uses a radial basis function (RBF) coupled with a polynomial basis function as a trial function, and uses the quartic spline function as

P. Xia; S. Y. Long; K. X. Wei

2011-01-01

124

Observation of spatter formation mechanisms in high-power fiber laser welding of thick plate  

NASA Astrophysics Data System (ADS)

This paper aims to present the dynamic behaviors of spatter formation, and to clarify the spatter formation mechanisms in the high-power fiber laser welding of a thick plate at low welding speeds. We used a modified "sandwich" specimen to directly observe the geometry of the longitudinal keyhole wall. The dynamic behaviors of the keyhole, vapor plume, and melt pool with the formation of spatters were observed using high-speed imaging. The mechanisms of the formation of the spatter ejected from the top and bottom surfaces were analyzed. The recoil momentum associated with the energized vapor plume jet acts on the tips of the gauffers on the front keyhole wall and micro-droplets inside the keyhole, thereby resulting in the formation of high-speed micro-spatter. At partial penetration, the spatter ejected from the keyhole inlet is influenced mainly by the upward melt flow above the keyhole, melt displacement around the keyhole, and the strong shear stream of the directed vapor plume force. Moreover, some spatter droplets are accelerated through the vapor plume outside the keyhole. At full penetration of the melt, spatters are generated when the downward momentum of the melt due to downward flow and gravity, or vapor burst with an open keyhole, exceeds the surface tension forces. At full penetration of the keyhole, the crucial driving force for spatter generation is the viscous friction drag associated with high-speed motion of the energized vapor plume through the open keyhole. The welding process evolves into almost a cutting process at a lower welding speed.

Zhang, M. J.; Chen, G. Y.; Zhou, Y.; Li, S. C.; Deng, H.

2013-09-01

125

Evaluation of standard and new chromogenic selective plating media for isolation and identification of Bacillus cereus  

Microsoft Academic Search

In this study, the performance of two new chromogenic plating media (CBC and BCM) was compared with two standard selective plating media (PEMBA and MYP) recommended by food authorities for isolation, identification and enumeration of Bacillus cereus. The four media types were challenged with a strain set comprising 100 B. cereus isolates from different origins and with different toxigenic potentials

Martina Fricker; Rolf Reissbrodt; Monika Ehling-Schulz

2008-01-01

126

Analysis of thick composite laminates using a higher-order shear and normal deformable plate theory (HOSNDPT) and a meshless method  

Microsoft Academic Search

The meshless local Petrov–Galerkin (MLPG) method with radial basis functions (RBFs), and the higher order shear and normal deformable plate theory (HOSNDPT) are used to analyze static infinitesimal deformations of thick laminated composite elastic plates under different boundary conditions. Two types of RBFs, namely, multiquadrics (MQ) and thin plate splines (TPS), are employed for constructing trial functions while a fourth

J. R. Xiao; D. F. Gilhooley; R. C. Batra; J. W. Gillespie Jr; M. A. McCarthy

2008-01-01

127

Mapping Crustal Thickness Variation and Relative Plate-Hotspot Motion for the Pacific Ocean using Satellite Gravity Inversion  

NASA Astrophysics Data System (ADS)

We determine crustal thickness for the Pacific Ocean, between 80oN to 80oS and 140oE to 295oE, using a gravity inversion method which incorporates a lithosphere thermal gravity anomaly correction (Greenhalgh & Kusznir, 2007; Chappell & Kusznir, 2008). Superposition of illuminated satellite gravity anomaly data onto crustal thickness maps from gravity inversion provides improved determination of sea-floor spreading trajectories, hot spot tracks and their inter-relationship. Data used in the gravity inversion are bathymetry, free-air gravity anomaly and sediment thickness from Sandwell and Smith (2008), Smith and Sandwell (2009) and Laske and Masters (1997) respectively. The gravity inversion method, which is carried out in the 3D spectral domain and predicts Moho depth, incorporates a lithosphere thermal gravity anomaly correction. Lithosphere thermal model re-equilibration (cooling) times, used to calculate the lithosphere thermal gravity anomaly correction, are conditioned by ocean isochron information (Mueller et al. 2008), and continental margin breakup ages. The lithosphere thinning distribution, used to define the initial thermal model temperature perturbation, may be defined using ocean isochron information or derived from the gravity inversion using no a priori isochron information. The resulting maps of crustal thickness with superimposed illuminated satellite gravity data show plate boundaries, micro-plates, micro-continents, oceanic plateaus and volcanic seamounts trails. The physical significance of the mapped parameter (i.e. crustal thickness) combined with its high resolution and broad scale allows observational links to be made between plate and hot-spot motion both present and past. Crustal thickness variation predicted by gravity inversion also shows intriguing relationships with tectonic fabric and roughness within oceanic lithosphere indicated by illuminated satellite free-air gravity data.

Sinclair, A.; Kusznir, N. J.; Alvey, A.

2011-12-01

128

Effect of film thickness on the structure and properties of nanocrystalline ZrN thin films produced by ion plating  

Microsoft Academic Search

Nanocrystalline ZrN thin films were successfully deposited on Si (100) and AISI 316 stainless steel (316SS) substrates using a hollow cathode discharge ion plating (HCD-IP) method. The objective of this study was to investigate the effect of film thickness on the composition, structure and mechanical properties of the ZrN films. The results showed that (111) was the dominant preferred orientation.

Jia-Hong Huang; Hao-Chung Yang; Xing-Jian Guo; Ge-Ping Yu

2005-01-01

129

Analysis and prevention of side cracking phenomenon occurring during hot rolling of thick low-carbon steel plates  

Microsoft Academic Search

In this study, a microstructural investigation was conducted on the side cracking phenomenon occurring in thick low-carbon steel plates during hot rolling. Particular emphasis was placed on the role of iron oxides and ferrite–pearlite band structure in the side cracking. Detailed microstructural analyses of the cracked region showed that the ferrite–pearlite band structure in the side region was considerably slanted

Byoungchul Hwang; Han Sang Lee; Yang Gon Kim; Sunghak Lee

2005-01-01

130

The effect of Au plating thickness of BGA substrates on ball shear strength under reliability tests  

Microsoft Academic Search

Each metal layer plated on BGA substrates has its own specific functions. The Ni layer is used as a barrier to prevent Cu from diffusing into solder balls, as the Cu interacts with Sn to form Sn-Cu intermetallic compounds (IMC). The IMC will then affect the shear strength of solder balls. A thin Au layer is also plated on top

S. C. Hung; P. J. Zheng; S. C. Lee; J. J. Lee

1999-01-01

131

Finite element analyses of irregular thick plates for signal pole design  

Microsoft Academic Search

The current specification of the American Association of State Highway and Transportation Officials does not specify any analysis method for the base plate design of span-wire-traffic-signal-poles. A simplified analysis method is developed here using finite element analysis for 28 signal poles, with calibration of the models by full-scale load testing. This method decomposes the base plate into three elementary components

Gongkang Fu; S. J. Boulos

1996-01-01

132

On dynamic behaviour of medium-thickness plates with uniperiodic structure  

Microsoft Academic Search

Summary An averaging 2-D model of a rectangular plate with unidirectional microperiodic structure is presented in this paper. The approach is partly based on the results exposed in [7]. The model describes the length-scale effect, i.e. the influence of the size of microstructure on the overall dynamic plate behaviour. This effect has not yet been considered in the literature on

E. Baron

2003-01-01

133

Coating thickness affects surface stress measurement of brush electro-plating nickel coating using Rayleigh wave approach.  

PubMed

A surface ultrasonic wave approach was presented for measuring surface stress of brush electro-plating nickel coating specimen, and the influence of coating thickness on surface stress measurement was discussed. In this research, two Rayleigh wave transducers with 5MHz frequency were employed to collect Rayleigh wave signals of coating specimen with different static tensile stresses and different coating thickness. The difference in time of flight between two Rayleigh wave signals was determined based on normalized cross correlation function. The influence of stress on propagation velocity of Rayleigh wave and the relationship between the difference in time of flight and tensile stress that corresponded to different coating thickness were discussed. Results indicate that inhomogeneous deformation of coating affects the relationship between the difference in time of flight and tensile stress, velocity of Rayleigh wave propagating in coating specimen increases with coating thickness increasing, and the variation rate reduces of difference in time of flight with tensile stress increasing as coating thickness increases. PMID:22534060

Liu, Bin; Dong, Shiyun; Xu, Binshi; He, Peng

2012-03-05

134

Deep Dry Etching of Quartz Plate Over 100 ?m in Depth Employing Ultra-Thick Photoresist (SU-8)  

NASA Astrophysics Data System (ADS)

The newly developed backside exposure method enabled us to easily fabricate a vertical/high aspect ratio ultra-thick photoresist (SU-8) pattern on a quartz plate. Deep quartz plate etching masked with SU-8 resist was studied employing an ICP etcher with a C4F8/H2/Ar gas mixture. Two issues took place in the long time etching. One was a corn-like defect generated on the quartz surface and the other was the variation of SU-8 etch rates during the etching process. The former was eliminated by a high bias cleaning process and an Ar plasma preheating process of the chamber wall improved the latter. Accordingly, a vertically etched profile of 100 ?m in depth was achieved.

Fukasawa, Takayuki; Horiike, Yasuhiro

2003-06-01

135

Optimum Fins Spacing and Thickness of a Finned Heat Exchanger Plate  

Microsoft Academic Search

The thermal design of a counterflow heat exchanger using air as the working fluid was performed with two distinct goals: minimum inlet temperature difference and minimum number of entropy generation units. The heat exchanger was constituted by a double-finned conductive plate closed by adiabatic walls at the fin tips on both sides. The hot and cold air flows were considered

Marcelo Moreira Ganzarolli; Carlos A. C. Altemani

2010-01-01

136

The finite element analysis on frequency shift of a piezoelectric plate operating in the thickness-shear mode under biasing fields  

Microsoft Academic Search

Based on the theory for small fields superposed on finite biasing fields, the finite element model of a high frequency, double-layer plate, thickness-shear vibration pressure sensor under biasing field is set up, and a biasing field finite element method (BFFEM) is proposed. Both ends of the piezoelectric plate, vibrating in thickness-shear mode, are subjected to bending moment and axial force,

Xing-ye Shan; Hong-ping Hu; Huan Xue; Yuan-tai Hu

2010-01-01

137

Vibro-acoustic response of an infinite, rib-stiffened, thick-plate assembly using finite-element analysis.  

PubMed

The vibration of and sound radiation from an infinite, fluid-loaded, thick-plate assembly stiffened periodically with ribs are investigated numerically using finite-element analysis. First, numerical simulations are compared to the analytical solutions presented recently for this particular problem [Hull and Welch, J. Sound Vib. 329, 4192-4211 (2010)]. It is shown that the solutions reported in this reference are partially incorrect because the number of modes was not chosen correctly. Subsequently, the numerical model is used to study the effect of repeated and equally spaced void inclusions on the vibro-acoustic response of the system. PMID:22779570

Remillieux, Marcel C; Burdisso, Ricardo A

2012-07-01

138

Propagation behaviors of thickness-twist modes in an inhomogeneous piezoelectric plate with two imperfectly bonded interfaces.  

PubMed

The thickness-twist modes in an inhomogeneous piezoelectric plate with two imperfectly bonded interfaces are analyzed, and an exact solution is obtained according to the spring-type relation from the equations of the linear theory of piezoelectricity. The frequency shift, the displacement and the stress components are all obtained and plotted. Both theoretical analysis and numerical examples show that the effect of mechanical imperfection is more evident than that of the electrical imperfection on the thickness-twist modes. Results show that the displacement and the stress components all change obviously due to the imperfectly bonded interfaces. The relationship between the frequency shift ?? and the non-dimensional number ? that is related to the imperfect interfaces is linear, which can be used to provide the foundation for a new experimental procedure for measuring the level of the interface bonding. PMID:21752416

Jin, Feng; Li, Peng

2011-06-21

139

Levy-Type Solution for Bending-Stretching of Thick Functionally Graded Rectangular Plates Based on Third-order Shear Deformation Theory  

Microsoft Academic Search

In this article, an analytical approach for bending-stretching analysis of thick functionally graded rectangular plates is presented. The governing equilibrium equations are obtained based on the third-order shear deformation plate theory. Introducing four new analytical functions and doing some algebraic operations, five highly coupled governing equilibrium equations are converted into two independent partial differential equations in terms of transverse displacement

A. R. Saidi; M. Bodaghi; S. R. Atashipour

2012-01-01

140

A shear-locking free robust isoparametric three-node triangular finite element for moderately-thick and thin arbitrarily laminated plates  

Microsoft Academic Search

A shear-locking free robust isoparametric three-node triangular finite element is developed for advanced fiber-reinforced arbitrarily laminated moderately-thick and thin plates. The strain-displacement relations are based on Reissner and Mindlin plate theory that accounts for transverse shear deformations into the plate formulation. A shear correction term is introduced into the finite element formulation to circumvent the shear locking effect. Numerical results,

H. R. H. Kabir

1995-01-01

141

Simplified model for oblique penetration of long-rod into plates of finite thickness  

NASA Astrophysics Data System (ADS)

A simplified calculation model describes the penetration phenomena of ricochet, embedment and perforation for long-rod penetrators impacting into homogeneous plates at various angles, and gives the profiles of craters and the bulge on the back of targets. The striking velocity range is from 900m/s to 1800m/s. The calculations for the model conform relatively well to test results.

Zhao, Guozhi

142

Influence of rim thickness on crack initiation life of wheel web plate for freight car  

Microsoft Academic Search

The temperature and stress distribution in freight car wheel are very important to the operation life. According to the data of investigation, the relationship among the wheel service life, crack rate on web hole and rim thickness is analyzed. The loads, boundary conditions and loading processes in the finite element analysis of temperature, stress field and wheel-railway mechanical stress are

Xiao Nan; Xie Jilong; Xie Yunye

2009-01-01

143

The dynamic mechanical properties study on the sandwich panel of different thickness steel plate-foam aluminum core  

NASA Astrophysics Data System (ADS)

The foam aluminum belongs to multi-cell materials, and it has good mechanical performance, such as large deformation capacity and good energy absorption, and usually used as core material of sandwich panel, now it is widely used in automotive, aviation, aerospace and other fields, particularly suitable for various anti-collision structure and buffer structure. In this article, based on an engineering background, the INSTRON4505 electronic universal testing machine and split Hopkinson pressure bar (SHPB) were used for testing the static and dynamic mechanical properties of sandwich panel with different thickness steel plate- foam aluminum core, from the results we can see that the steel plate thickness has big influence on the stress-strain curve of the sandwich panel, and also takes the sandwich panel with 1mm steel panel to study the material strain rate dependence which under different high shock wave stress loaded, the results show that the sandwich panel is strain rate dependence material. And also, in order to get good waveforms in the SHPB experiment, the waveform shaped technique is used in the dynamic experiments, and the study of this paper will good to sandwich panel used in the engineering.

Chang, Zhongliang; Zou, Guangping; Zhao, Weiling; Xia, Peixiu

2009-12-01

144

Dielectric and piezoelectric properties of stacked and plated PVDF, P(VDF\\/TeFe), P(VDF\\/TrFE) and ceramic\\/rubber composite thick films  

Microsoft Academic Search

We measured the properties of nine different piezoelectric materials, as supplied, and as further processed to increase their hydrostatic sensitivity. We studied the effect of electrode material, stiffening plates, and multiple layering on the piezoelectric and dielectric properties of the thick piezopolymer films. Dielectric measurements and thickness mode d3t, lateral mode d31 (d32), and hydrostatic mode dh piezoelectric coefficients were

Philip E. Bloomfield

1994-01-01

145

78 FR 59065 - Interview Room Recording System Standard and License Plate Reader Standard Workshops  

Federal Register 2010, 2011, 2012, 2013

...Programs [OJP (NIJ) Docket No. 1632] Interview Room Recording System Standard and License...Department of Justice. ACTION: Notice of the Interview Room Recording System Standard and License...development of NIJ performance standards for Interview Room Recording Systems and License...

2013-09-25

146

78 FR 65554 - Exhaust Emission Standards for New Aircraft Turbine Engines and Identification Plate for Aircraft...  

Federal Register 2010, 2011, 2012, 2013

...45 [Docket No.: FAA-2012-1333; Amendment No. 34-5A] RIN 2120-AK15 Exhaust Emission Standards for New Aircraft Turbine Engines and Identification Plate for Aircraft Engines Correction In rule document 2013-24712, appearing on pages...

2013-11-01

147

Thick Plate Rolling--a Numerical Approach in Comparison with Analytics and Experimental Data  

NASA Astrophysics Data System (ADS)

Today, wind turbines are mostly made of glass or carbon fibre. The manufacturing process leads to high precision and quality of the final product. Nevertheless, this fabrication method of rotor blades is very cost intensive and its production technology is not the best in terms of recyclability. In addition to its good recyclability, the handling of steel is well known and its fabrication is inexpensive. Due to these facts an idea of foils to be produced from steel arose. In cooperation with a metal forming company the 3-Dimensional rolling concept came up. Initially, rolling experiments with cold lead plates in a scale of 1:4 are made to simulate the later on used hot steel plates. Such an approach has to be accompanied by fundamental research. This paper sketches the lead rolling experiment and gives an assessment if it is applicable for a hot rolling process with steel. For this purpose, the lead test data are interpreted, the numerical model is explained and results are presented. Furthermore, an analytical flat rolling approach is used to calculate process parameters like stamping force of the upper roll and necessary friction. The applicability and precision of the analytical results are discussed in comparison with the results of the FEM model and the experimental data. Concluding the paper, validity and pitfalls of this concept are outlined and a short outlook for further research is given. The purpose of these considerations is to get closer to process parameters for an experiment in full scale for hot rolling of a rotor blade.

Prommer, Hannes; Bojahr, Manuel; Tschullik, Ralf; Kaeding, Patrick

2011-05-01

148

Transmission analysis of ultrasonic Lamb mode conversion in a plate with partial-thickness notch.  

PubMed

Mode conversions of Lamb waves can occur upon encountering damage or defect such as a notch, leading to newly-converted modes apart from wave reflection and transmission. In this paper, the transmission of the fundamental Lamb modes symmetrical S0 and anti-symmetrical A0 with anti-symmetrical notches were investigated in steel plates within the relatively short propagation distance. The group velocity and modal energy of the converted modes were analyzed using simulations and experiments. Two-dimensional finite difference time domain (2D-FDTD) method was employed to calculate the scattering field and extract numerical trends for simulation study and experimental confirmation. Both simulations and experiments revealed that the apparent group velocities of the converted modes in the transmitted signals subject to the notch positions. To describe the mode conversion degree and evaluate the notch severity, wave packets of the originally-transmitted modes and newly-converted modes were separated and corresponding mode energy percentages were analyzed at different notch severities. Frequency-sweeping measurements illustrated that the modal energy percentages varied monotonically over the notch-depth increase with a statistically consistency (R=1.00, P<0.0004). PMID:23916666

Xu, Kailiang; Ta, Dean; Su, Zhongqing; Wang, Weiqi

2013-07-18

149

Simulation results on a resistive plate chamber for a bakelite thickness of 1 mm up to 3 mm  

SciTech Connect

The performance of bakelite electrodes with thicknesses of 1, 2, and 3 mm in a double-gap resistive plate chamber (RPC) have been tested by GEANT-based Monte Carlo simulation. Results show that the thickness of bakelite plays an important role in detecting particle signals. For checking the efficiency of these RPCs, gamma particles in the range 0.01-100 MeV have been simulated through different bakelite setups. For an isotropic gamma source, a sensitivity s{sub {gamma}}<3.5x10{sup -2} at <100 MeV by a 1 mm bakelite double-gap RPC has been observed. For the same gamma source with a 2 mm bakelite RPC, a sensitivity s{sub {gamma}}<4.0x10{sup -2} at <100 MeV has been measured, whereas for 3 mm bakelite RPC, sensitivity results were s{sub {gamma}}<4.44x10{sup -2} at <100 MeV. Similar characteristics of bakelite electrodes have been observed for a parallel gamma source configuration.

Rhee, J.T.; Jamil, M. [Institute for Advanced Physics, Konkuk University, Seoul 143-701 (Korea, Republic of)

2005-07-15

150

A Computational Study of Segmented Tungsten Rod Penetration into a Thick Steel Target Plate at High Velocities  

NASA Astrophysics Data System (ADS)

This paper presents results from computational simulations of tungsten alloy segmented rod projectiles (SRP) penetrating an RHA semi-infinite target plate at high velocities. For SRP with an aspect ratio (L/D) = 1/8, a loss in penetration efficiency was seen upon successive segment impacts. Numerical simulations of a configuration in which a tungsten heavy alloy SRP penetrated a thick RHA 4340 steel at 2.6 km/s were performed using the 2006 version of the EPIC - a Lagrangian code. The configuration consisted of eight collinear impacts of discs which measured 2mm thick and 16mm in diameter. The numerical simulations considered a range of parameters including element-particle conversion, spacing and number of fragments, failure criterion, and mesh resolution that influenced the Depth of Penetration (DOP). The EPIC results using the element-to-particle conversion capability in the EPIC code are also compared with open-literature DOP data from simulations using an Eulerian finite element code, AUTODYN for a similar configuration. The present results showed a unique phenomenon of back-flowing ejecta from the crater and fragmented segments penetrating the in-coming subsequent segment. The penetration efficiency seems to be influenced by the back-flowing ejecta. Further computational investigation considered additional simulations with an impact configuration designed to minimize the ejecta effects by using washer-shaped segments; however, the results showed insignificant improvement.

Presnell, M.; Rajendran, A.

2011-06-01

151

Nonlinear Dynamic Finite Element Analysis of Thick Transversly Flexible Sandwich Panel on Elastic Foundation with Account of Damage Progression in Time. Part 1. Three-Dimensional Formulation and Two-Dimensional Plate Theory  

Microsoft Academic Search

In order to construct a plate theory for a thick transversely compressible sandwich plate with composite laminated face sheets, the author makes simplifying assumptions regarding distribution of transverse strain components in the thickness direction. It is assumed that the transverse strains, i.e., exz, eyz, and ezzdo not vary in the thickness direction within the face sheets and the core, but

V. Y. Perel

2005-01-01

152

3D THERMO-VISCOPLASTIC MODELING OF WELDS: EFFECT OF PIECE-WISE WELDING ON THERMOMECHANICAL RESPONSE OF THICK PLATE WELDMENTS  

Microsoft Academic Search

The effect of piece-wise welding on thermal and mechanical response of thick plate weldments is studied by the use of a 3-D thermo-viscoplastic model. Anand's viscoplastic model is used to simulate the rate dependent plastic deformation of welded materials. Modeling of the welded region in the present study has been done by the use of the \\

M. R. NAMI; M. H. KADIVAR; K. JAFARPUR

153

Factors that influence elastomeric coating performance: the effect of coating thickness on basal plate morphology, growth and critical removal stress of the barnacle Balanus amphitrite  

Microsoft Academic Search

Silicone coatings are currently the most effective non-toxic fouling release surfaces. Understanding the mechanisms that contribute to the performance of silicone coatings is necessary to further improve their design. The objective of this study was to examine the effect of coating thickness on basal plate morphology, growth, and critical removal stress of the barnacle Balanus amphitrite. Barnacles were grown on

D. E. Wendt; G. L. Kowalke; J. Kim; I. L. Singer

2006-01-01

154

The Influence Exerted by Weld Seam Throat and Plate Thickness on the Fatigue Strength of Weld Joints Made by Means of Fillet Welds.  

National Technical Information Service (NTIS)

An investigation was carried out to determine the influence exerted by weld seam throat and plate thickness on the fatigue strength of the transition areas of fillet welds. The statistical test program covered angular test pieces made from grade MRSt 37-2...

E. Haibach R. Olivier W. Ritter

1978-01-01

155

X-Ray Fluorescence On-Stream Analysis of Standard Reference Solution Concentrations of Chromium Plating and Polishing Solutions.  

National Technical Information Service (NTIS)

X-ray fluorescence is evaluated as a means to quantitatively analyze standard reference solution concentrations of chromium plating and polishing solutions for chromium, sulfur, phosphorus, and iron in a continuous, on-stream fashion. The identical experi...

S. Sopok

1991-01-01

156

76 FR 35806 - Amendments to National Emission Standards for Hazardous Air Pollutants for Area Sources: Plating...  

Federal Register 2010, 2011, 2012, 2013

...nonchromium electroplating; electropolishing; electroforming; electroless plating, including thermal metal spraying, chromate conversion...nonchromium electroplating; electropolishing; electroforming; electroless plating, including thermal metal spraying, chromate...

2011-06-20

157

Effect of volume fraction and shape of sulfide inclusions on through-thickness ductility and impact energy of high-strength 4340 plate steels  

Microsoft Academic Search

The effect of volume fraction and shape of sulfide inclusions on the tensile ductility and impact energy of high-strength\\u000a AISI 4340 plate steels in the transverse and through-thickness testing directions was investigated for four tensile-strength\\u000a levels of 930, 1210, 1410, and 1960 MPa (135, 175, 205, and 285 ksi). The volume fraction of sulfide inclusions was changed\\u000a by varying the

G. R. Speich; W. A. Spitzig

1982-01-01

158

Static and Dynamic Analysis of Thick Functionally Graded Plates with Piezoelectric Layers Using Layerwise Finite Element Model  

Microsoft Academic Search

In this paper, static and dynamic analysis of a functionally graded material (FGM) plate with surface-bonded piezoelectric layers is studied. A general finite element formulation based on the layerwise theory is developed for modelling an FG plate with piezoelectric layers or patches. The intermediate FG layer is assumed to be made of many sublayers. Each sublayer is considered as an

M. Shakeri; R. Mirzaeifar

2009-01-01

159

Simple Method for Plating Escherichia coli Bacteriophages Forming Very Small Plaques or No Plaques under Standard Conditions  

Microsoft Academic Search

The use of low concentrations (optimally 2.5 to 3.5 g\\/ml, depending on top agar thickness) of ampicillin in the bottom agar of the plate allows for formation of highly visible plaques of bacteriophages which otherwise form extremely small plaques or no plaques on Escherichia coli lawns. Using this method, we were able to obtain plaques of newly isolated bacteriophages, propagated

J. M. Los; Piotr Golec; G. Wegrzyn; A. Wegrzyn; M. Los

2008-01-01

160

Free and Forced Vibrations of Thick Rectangular Plates using Higher-Or~er Shear and Normal Deformable Plate Theory and Meshless Petrov-Galerkin (MLPG) Method  

Microsoft Academic Search

We use a meshless local Petrov-Galerkin Liu (2001) have used the MLPG method to find natu- (MLPG) method to analyze three-dimensional infinitesi- ral frequencies and forced plane ,strain deformations.of mal elastodynamic deformations of a homogeneous rect- a cantilever beam. Batra and Chmg .(2002~ have de!m- angular plate subjected to different edge conditions. We eated the time evolution of the stress-mtenslty

L. F. Qianl; R. C. Batra; L. M. Chenl

2003-01-01

161

Detection of Proximal Caries in vitro Using Standard and Task-Specific Enhanced Images from a Storage Phosphor Plate System  

Microsoft Academic Search

Eight dentists evaluated 72 proximal surfaces of premolars with respect to all caries lesions and to lesions into dentine in digital images from a storage phosphor plate system. The images were processed in four different ways: (1) the default algorithm of the standard imaging system (DF); (2) an algorithm correcting for attenuation and visual response (AV), and two proprietary caries-specific

G. Li; G. C. H. Sanderink; W. E. R. Berkhout; K. Syriopoulos; P. F. van der Stelt

2007-01-01

162

Selection of antibiotic-resistant standard plate count bacteria during water treatment.  

PubMed Central

Standard plate count (SPC) bacteria were isolated from a drinking-water treatment facility and from the river supplying the facility. All isolates were identified and tested for their resistance to six antibiotics to determine if drug-resistant bacteria were selected for as a consequence of water treatment. Among the isolates surviving our test procedures, there was a significant selection (P less than 0.05) of gram-negative SPC organisms resistant to two or more of the test antibiotics. These bacteria were isolated from the flash mix tank, where chlorine, alum, and lime are added to the water. Streptomycin resistance in particular was more frequent in this population as compared with bacteria in the untreated river water (P less than 0.01). SPC bacteria from the clear well, which is a tank holding the finished drinking water at the treatment facility, were also more frequently antibiotic resistant than were the respective river water populations. When 15.8 and 18.2% of the river water bacteria were multiply antibiotic resistant, 57.1 and 43.5%, respectively, of the SPC bacteria in the clear well were multiply antibiotic resistant. Selection for bacteria exhibiting resistance to streptomycin was achieved by chlorinating river water in the laboratory. We concluded that the selective factors operating in the aquatic environment of a water treatment facility can act to increase the proportion of antibiotic-resistant members of the SPC bacterial population in treated drinking water.

Armstrong, J L; Calomiris, J J; Seidler, R J

1982-01-01

163

Parallel-plate resonator of variable spacer thickness for accurate measurements of surface impedance of high-Tc superconductive films  

Microsoft Academic Search

Measurements of microwave surface impedance of high-Tc films at gigahertz frequencies and nitrogen temperature are performed. A simple technique employing a parallel-plate resonator with liquid nitrogen as a dielectric spaces is suggested. The use of a precise mechanical device provides smooth changing of distance between films from 200 microns down to zero. Coupling to the resonator is accomplished by means

A. Ia. Basovich; R. K. Belov; V. A. Markelov; L. A. Mazo; S. A. Pavlov; V. V. Talanov; A. V. Varganov

1992-01-01

164

Multilayered Plate Model with “Adaptive” Representation of Displacements and Temperature Across the Thickness and Fixed D.O.F  

Microsoft Academic Search

A new multilayered zig-zag plate model for analysis of thermo-elastic problems is developed. It a priori fulfils the boundary conditions and the stress contact conditions on interlaminar shear and normal stresses and the continuity of the heat flux and temperature at the layer interfaces, as prescribed by the elasticity theory and heat conduction equation. The functional d.o.f. are the mid-plane

Ugo Icardi

2011-01-01

165

Parallel-plate resonator of variable spacer thickness for accurate measurements of surface impedance of high- T c superconductive films  

Microsoft Academic Search

Measurements of microwave surface impedance of high-Tc films at gigahertz frequencies and nitrogen temperature are performed. A simple technique employing a parallel-plate resonator with liquid nitrogen as a dielectric spaces is suggested. The use of a precise mechanical device provides smooth changing of distance between films from 200µm down to zero. Coupling to the resonator is accomplished by means of

A. Ya. Basovich; R. K. Belov; V. A. Markelov; L. A. Mazo; S. A. Pavlov; V. V. Talanov; A. V. Varganov

1992-01-01

166

Relative influence of surficial, climatic, and plate tectonic processes on the development of thick Paleoproterozoic quartz arenite successions  

Microsoft Academic Search

Quartz arenites are significant components of the rock record and appear to be most abundant during specific time intervals in Earth history. Thick quartz arenite successions are typical in Precambrian strata and have been associated with extensive cratonization during the late Archean to early Proterozoic. These supermature sandstones can also be attributed to the intense weathering conditions of early Earth's

P. Corcoran; L. Bynoe

2010-01-01

167

Practical Bench Comparison of BBL CHROMagar Orientation and Standard Two-Plate Media for Urine Cultures  

Microsoft Academic Search

A total of 1,023 urine samples sent for routine culture were plated onto sheep blood and MacConkey agars and a BBL CHROMagar Orientation (CO; Becton Dickinson, Cockeysville, Md.) plate, and the results were compared. Of these, 250 urine samples (24%) grew >10,000 CFU of one or two putative pathogens\\/ml and 773 showed no growth (NG), mixed growth of <10,000 CFU\\/ml,

Holly A. D'Souza; Mary Campbell; Ellen Jo Baron

168

Practical Bench Comparison of BBL CHROMagar Orientation and Standard Two-Plate Media for Urine Cultures  

Microsoft Academic Search

A total of 1,023 urine samples sent for routine culture were plated onto sheep blood and MacConkey agars and a BBL CHROMagar Orientation (CO; Becton Dickinson, Cockeysville, Md.) plate, and the results were compared. Of these, 250 urine samples (24%) grew >10,000 CFU of one or two putative pathogens\\/ml and 773 showed no growth (NG), mixed growth of <10,000 CFU\\/ml,

Holly A. D'Souza; Mary Campbell; Ellen Jo Baron

2004-01-01

169

A computational study of segmented tungsten rod penetration into a thick steel target plate at high velocities  

NASA Astrophysics Data System (ADS)

This paper presents results from numerical simulations of a configuration in which a tungsten heavy alloy SRP penetrates a thick RHA 4340 steel at 2.6 km/s using the 2006 version of the Lagrangian finite element code EPIC. Penetration experimental data show improved penetration efficiency by the segmented projectiles when compared to monolithic (single solid rod) projectiles. For SRP with an aspect ratio (L/D) = 1/8, a loss in penetration efficiency was seen upon successive segment impacts. The projectile configuration considered in this study was collinear impacts of eight successive discs which measured 2mm in thickness and 16mm in diameter. The EPIC simulations considered a range of parameters that influenced the Depth of Penetration (DOP) including element-particle conversion, spacing and number of segments, failure criteria, impact velocity, and mesh resolution. The EPIC results are also compared with open-literature DOP data from simulations using an Eulerian finite element code, AUTODYN for a similar configuration. In addition, the effects of back-flowing ejecta generated by the impact of first segment on the penetration processes of subsequent segments were studied in details. An alternate SRP design is proposed in this paper to alleviate the ejecta problem.

Presnell, Michael B.; Rajendran, A. M.

2012-03-01

170

Relative influence of surficial, climatic, and plate tectonic processes on the development of thick Paleoproterozoic quartz arenite successions  

NASA Astrophysics Data System (ADS)

Quartz arenites are significant components of the rock record and appear to be most abundant during specific time intervals in Earth history. Thick quartz arenite successions are typical in Precambrian strata and have been associated with extensive cratonization during the late Archean to early Proterozoic. These supermature sandstones can also be attributed to the intense weathering conditions of early Earth’s atmosphere, source rocks rich in quartz, recycling and diagenesis, or simply the higher preservation potential of quartz compared with other minerals. Modern quartz-rich sands develop in low relief settings where high residence times contribute to chemical breakdown of labile grains. The lack of land vegetation during the Precambrian would have precluded confined sedimentation patterns and stabilization of soils, both of which enhance sediment residence times. Thus, the generation of first-cycle late Archean quartz arenites in fault-controlled, high relief basins necessitates periods of intense chemical weathering. The inferred change from a greenhouse to oxygenated atmosphere at around 2.3-2.2 Ga could have been the major control on the relative change to thinner units of pure sandstones with time. In order to test this hypothesis, detailed facies and compositional analyses are being conducted on the ca. 2.2 Ga Bar River Formation of the Huronian Supergroup, Canada. Four groups comprise Huronian stratigraphy, three of which contain basal glaciogenic conglomerates, followed by mudstone-dominated then quartz-rich formations. It has been suggested that these tripartite cycles could have been climatically controlled. Detailed facies analysis of the 500-750 m thick quartz arenite indicates shallow water, wave-influenced settings, akin to shoreface environments along extensive stable shelves. Thin mudstone interbeds, representing brief periods of suspension sedimentation, have been sampled for geochemical analysis in order to determine the degree of chemical weathering that occurred. Preliminary investigations of heavy mineral suites have indicated an abundance of the stable minerals zircon and tourmaline, which is consistent with physical and chemical weathering. Depending on preservation, detailed examination of quartz and heavy mineral surface textures and grain boundaries using SEM could provide an idea of the relative degree of recycling versus chemical erosion that has occurred. Finally, the Bar River Formation is primarily exposed as the “core” of a string of islands stretching approximately 40 km within Lake Huron. Preservation of the quartz arenite, but not the over- and underlying formations reflects how it better withstands billions of years of weathering and erosion compared with other less pure sedimentary rocks. Thus the apparent abundance of thick ancient quartz arenite relative to younger examples may simply be a function of mineral stability.

Corcoran, P.; Bynoe, L.

2010-12-01

171

Plate-Tectonic Analysis of Shallow Seismicity: Apparent Boundary Width, beta-Value, Corner Magnitude, Coupled Lithosphere Thickness, and Coupling in 7 Tectonic Settings  

NASA Astrophysics Data System (ADS)

A new plate model [Bird, 2003, G3, 10.1029/2001GC000252] is used to analyze the mean seismicities of 7 types of plate boundary (CRB continental rift boundary, CTF continental transform fault, CCB continental convergent boundary, OSR oceanic spreading ridge, OTF oceanic transform fault, OCB oceanic convergent boundary, SUB subduction zone). We compare the plate-like (non-orogen) regions of model PB2002 with the CMT catalog to select apparent boundary half-widths, and then assign 95% of shallow earthquakes to one of these settings. A tapered Gutenberg-Richter model of the frequency/moment relation is fit to the subcatalog for each setting by maximum-likelihood. Best-fitting ? values range from 0.53 to 0.92, but all 95%-confidence ranges are consistent with a common value of 0.61-0.66. To better determine some corner magnitudes we expand the subcatalogs by: (1) inclusion of orogens; and (2) inclusion of years 1900-1975 from the catalog of Pacheco and Sykes [1992]. Combining both earthquake statistics and the plate-tectonic constraint on moment rate, corner magnitudes include: CRB 7.64-.26+.76, CTF 8.01-.21+.45, CCB 8.46-.39+.21, OCB 8.04-.22+.52, and SUB 9.58-.46+.48. Coupled lithosphere thicknesses are found to be: CRB 3.0-1.4+7.0 km; CTF 8.6-4.1+11 km; CCB 18-11+? km; OSR 0.13-0.09+.13 km for normal-faulting and 0.40-.21+? km for strike-slip; OTF 12-7.1+?, 1.6-0.5+1.4, and 1.5-0.6+1.2 km at low, medium, and high velocities; OCB 3.8-2.3+13.7 km, and SUB 18.0-10.8+? km. Generally high coupling of subduction and continental plate boundaries suggests that here all seismic gaps are dangerous unless proven to be creeping. Generally low coupling within oceanic lithosphere suggests a different model of isolated seismic asperities surrounded by large seismic gaps which may be permanent.

Bird, P.; Kagan, Y. Y.

2003-12-01

172

A Study on the Application of Submerged Arc Welding for Thin Plate of A-Grade 3.2 Thickness Steel in Ship Structure  

NASA Astrophysics Data System (ADS)

This paper is focused on application submerged arc welding process, which offers many advantages compared to conventional CO2 welding process, for thin plate in ship structure. For this purpose, optimized welding conditions are determined according to combination of wire & flux, relationship between welding parameters, bead shapes and mechanical tests such as tensile, bend and hardness. Also finite element(FE) based numerical simulation of thermal history and welding residual stress in welded joint of A-grade 3.2 thickness steel has been checked to qualitative tendency in this paper. In conclusion our company applied to this method in work piece and it was no problem. From the result of this study, it makes substantial saving of time and manufacturing cost and raises the welding quality of product.

Lee, Jeong-Soo; Yun, Jin-Oh; Lim, Dong-Yong; Jang, Yong-Won; Kim, Bong-Joon; Oh, Chong-In

2010-06-01

173

Review of Consensus Standard Spectra for Flat Plate and Concentrating Photovoltaic Performance  

SciTech Connect

Consensus standard reference terrestrial solar spectra are used to establish nameplate ratings for photovoltaic device performance at standard reporting conditions. This report describes reference solar spectra developed in the United States and international consensus standards community which are widely accepted as of this writing (June 2011).

Myers, D.

2011-09-01

174

A 3D shell-like approach using element-free Galerkin method for analysis of thin and thick plate structures  

NASA Astrophysics Data System (ADS)

A new efficient meshless method based on the element-free Galerkin method is proposed to analyze the static deformation of thin and thick plate structures in this paper. Using the new 3D shell-like kinematics in analogy to the solid-shell concept of the finite element method, discretization is carried out by the nodes located on the upper and lower surfaces of the structures. The approximation of all unknown field variables is carried out by using the moving least squares (MLS) approximation scheme in the in-plane directions, while the linear interpolation is applied through the thickness direction. Thus, different boundary conditions are defined only using displacements and penalty method is used to enforce the essential boundary conditions. The constrained Galerkin weak form, which incorporates only displacement degrees of freedom (d.o.f.s), is derived. A modified 3D constitutive relationship is adopted in order to avoid or eliminate some self-locking effects. The numeric efficiency of the proposed meshless formulation is illustrated by the numeric examples.

Yin, Yu; Yao, Lin-Quan; Cao, Yang

2013-02-01

175

Within-plate magmatism under condition of abnormally thick sialic crust: Evidence for Proterozoic anorthosite-rapakivi granite complexes of the East-European Craton  

NASA Astrophysics Data System (ADS)

Mid-Proterozoic (1.8-1.5 Ga) large bimodal multistage anorthosite-rapakivi granite complexes (ARGCs) are distinct magmatic assemblages in central part of the East European Craton. ARGCs formation commenced after stabilization of the Svecofennian orogen and relics of its abnormally thick (up to 50-60 km now) crust survived here in many places. Such massifs are practically absent at the eastern part of the craton (Kola-Karelian, Volga-Urals, etc. domains) with normal thickness (~40 km) of the crust. The ARGCs formation was accompanied by emplacement of diabase, quartz porphyry and complex dike swarms. Intra-plutonic diabase dikes (Fe-Ti basalts plume-related type), intruding the rapakivi granites, are often crossed in turn by later portions of granites; injections of basaltic melt into granitic magma chambers resulted in magma mingling. It indicates that melted out occurred simultaneously in mantle and crust during ARGC formation. Geochemical peculiarities of the ARGC rocks are enrichment in alkali (especially in K), Ti, Zn, Pb, and Zr, relatively high concentrations of Be, Sn, In, Y, Nb, Rb, F, Cu, W and Mo, and sometimes - Li and U. ?Nd value, ranges from -1.2 to +1.6, and relative high Th and Zn contents, most frequently observable in anorthosites, imply that the mafic magmas were considerably contaminated by crustal components. According to geophysical data, ARGCs represent upper parts of large transcrustal systems, composed by alternation of basic and silicic rocks, which located above rises of the mantle up to 10-20 km high. Such localization of ARGCs, probably evidence that such protuberances were mantle plume heads in time, where melting of their material occurred due to adiabatic decompression. Newly-formed basaltic melts (apparently Fe-Ti basalts, similar in composition to intra-plutonic dike rocks) intruded at different depths into abnormally thick sialic crust of stabilized by then Svecofennian orogen in form of large sills and caused melting of crustal material above them. As a result, complex magmatic systems appeared here. Partial melting of the crust was the consequence of advective heating from the hot mantle magmas. Due to convection, the main heat loss during solidification was realized through roofs of basaltic sills. Consequently, extensive melting of warmed-up siliceous rocks above them would be occurred, at that thickness of newly formed granitic layer could twice exceed the thickness of basaltic sill (Huppert and Sparks, 1988). During the initial stages relatively cool crustal material at the boundary of basaltic melt and sialic roof involved in convective flows and dissolved in hot basaltic melt, which led to it's enrichment in SiO2 and Al2O3., led to predomination of plagioclase cumulates among the rocks of basic sections. Solidification of such complex chambers were began from hardening of lower basic layers; it led to domination of ascending currents in the upper silicic layer, which was favour to appearance of specific rapakivi textures in granites. ARGCs are usually associated with large Mid-Proterozoic belts of within-plate felsic volcanism, developed on all Precambrian shields on place of stabilized Paleoproterozoic orogens with thick sialic crust. From such point of view, it was the main reason for existence of such volcanism, because majority of mantle-derived mafic magmas was not reached the surface and secondary felsic melts were predominated. Evidently, ARGCs illustrate structure and processes in transitions magma chambers of such peculiar magmatic systems. Many investigators suggest that ARGCs are a part of anorthosite-mangerite-charnockite granite (AMCG) suite. However, typical AMCG complexes were commonly developed in mobile zones and undergone by deformation and high-grade metamorphism. In contrast, anorogenic ARGCs are usually localized among stabilized domains and appeared on places where Paleoproterozoic orogens completed their development. So, their tectonic settings can be described in terms of within-plate activity, distinctive from the settings of the AMCG suite.

Sharkov, Evgenii

2010-05-01

176

Correction of Thick Foil Errors in Prompt Neutron (CALIFORNIUM-252 Nu), Fission Cross Section (sigma(f)) and Other Ionization Chamber Fission Data Standards.  

NASA Astrophysics Data System (ADS)

This research resolves two problems that have long been of important concern in experimental fission physics: (1) determination of pulse height distribution response of ionization chambers in fission fragment detection measurements, and (2) correction of "thick-foil effect" systematic errors in standard values of the fundamental parameters of fission physics--the average number of prompt neutrons per fission (=nu), absolute fission activity and true fission rate of samples (TFR), and isotopic fission cross sections (sigma _{f}). Results are obtained by a comprehensive digital simulation of the electrostatics and pulse height distribution response of the parallel-plate, ungridded, electron-pulse ionization fission chamber together with prompt neutron -fragment multiplicity and angular distribution correlations, neutron-fragment coincidence detection and related variations in the 4pi^here around the chamber for a wide range of the relevant factors--foil thickness, alpha particle interference bias level, fission detector configuration characteristics, fissile isotopes (^{252}Cf, ^{235}U, etc.) and other experimental parameters. Isotope-specific double-energy (E_1,E_2) natural variations in fragment spectrum, in fragment-specific range-energy (dE/dx) relations and in prompt neutron-fragment multiplicity (nu) and nuclear temperature dependent angular distribution correlations are simulated in detail. Detailed results are obtained for double-energy, fragment-specific count loss fractions resulting from in -foil fragment absorption and from alpha -interference discrimination as well as for chamber detection efficiency, fragment spectrum distortion and prompt neutron -fragment coincidence detection distribution variations. Decay alpha pulse pileup statistics are discussed, and the behavior of and factors affecting the fragment pulse height distribution tail are analyzed in detail. Fragment pairs and prompt neutrons issued from them are tracked in the 4pi^ace around the chamber. Light-to-heavy fragment detection ratio variations in neutron-gated coincidence measurements are also obtained in 4pi space. Effects of these systematics on absolute, relative and ratio measurements of fundamental fission parameters are discussed. Magnitudes and mechanisms of production of thick-foil errors are identified and analyzed in detail, and methods for correcting these errors and for improving measurement setup design are given.

Cohensedgh, Farhad

177

Experimental Techniques for Laser-Launching Miniature (2 - 50 micron, thick) Flyer Plates for 1-D Impacts for Dynamic Property Measurements  

Microsoft Academic Search

Laser-launched miniature flyer plates are used to measure dynamic property of materials such as, EOS, stress-strain, and spall strength. The miniature flyer plates are typically 3-mm diameter by 2-50 micron thck and can be of almost any solid phase material. Because the flyer plate is laser-launched the laser deposition parameters are decoupled from the flyer plate. Thin flyer plates travelling

D. L. Paisley; S. A. Sheffield; D. B. Stahl

1997-01-01

178

Comparison of 3M Petrifilm Aerobic Count Plates to standard plating methodology for use with AOAC antimicrobial efficacy methods 955.14, 955.15, 964.02, and 966.04 as an alternative enumeration procedure: collaborative study.  

PubMed

A multilaboratory study was conducted to determine the equivalence of the 3M Petrifilm Aerobic Count Plate and standard plating methodology for measuring viable bacteria and spores recovered from hard-surface carriers (stainless steel and porcelain), also known as "control carrier counts," used in AOAC antimicrobial efficacy test methods. Six laboratories participated in the study in which carriers inoculated with Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella enterica, and spores of Bacillus subtilis were evaluated using 3M Petrifilm Aerobic Count (AC) plates and standard plating side-by-side. The data were analyzed using a matched-pair t-test to determine the between-method effect with confidence intervals. For all test organisms pooled across all laboratories, the mean difference in log10 concentration between the standard plate count method and 3M Petrifilm AC Plates was -0.012, with a 95% confidence interval of (-0.090, +0.066), which was well within the -0.5, +0.5 interval established as the acceptance criterion. The between-carrier SD averaged 0.139; the between-replicate SD was 0.050. The carrier reproducibility, given that a single replicate per carrier is done, was estimated to be 0.148. Although differences were seen in the final concentrations of the test organisms among laboratories, there were no statistical differences between the enumeration methods. Based on the results from this study, 3M Petrifilm AC Plates are equivalent to standard plating methodology and can be used as an alternative procedure for the enumeration of test organisms used in AOAC Methods 955.14, 955.15, 964.02, and 966.04. PMID:24000742

Nelson, Maria T; LaBudde, Robert A; Tomasino, Stephen F; Pines, Rebecca M

179

Practical Bench Comparison of BBL CHROMagar Orientation and Standard Two-Plate Media for Urine Cultures  

PubMed Central

A total of 1,023 urine samples sent for routine culture were plated onto sheep blood and MacConkey agars and a BBL CHROMagar Orientation (CO; Becton Dickinson, Cockeysville, Md.) plate, and the results were compared. Of these, 250 urine samples (24%) grew >10,000 CFU of one or two putative pathogens/ml and 773 showed no growth (NG), mixed growth of <10,000 CFU/ml, or three or more strains (mixed). The CO and conventional medium results agreed completely for 595 cultures with NG or <10,000 CFU/ml. An additional 178 urine samples yielded clinically insignificant differences. Both medium sets essentially agreed on quantities and identification for 400 single-pathogen cultures and 9 mixed cultures. With the caveat that CO cannot differentiate Klebsiella, Enterobacter, and Serratia spp., enteric pathogens were identified only by morphology and color on CO. Direct visual differentiation of group B streptococci from lactobacilli is not possible, but lactobacillus cells always exhibited easily recognizable morphology on Gram stain. Of 108 paired organism susceptibility results encompassing 2,268 drug-pathogen combinations, there were 3% errors and only 1% very major errors. Use of CO allowed a >50% reduction in inoculation time and a >20% reduction in work-up time. For our laboratory, with 50% “no growth” and ca. 25% significant results (50% Escherichia coli), CO allowed time and workup cost savings for a majority of cultures. A cost analysis (time and supplies for our laboratory) showed that if CO is used alone, the break-even level for CO pricing is $1.78; if CO and blood agar are both used, the break-even pricing for CO is $1.53.

D'Souza, Holly A.; Campbell, Mary; Baron, Ellen Jo

2004-01-01

180

Plate Tectonics  

NSDL National Science Digital Library

The Plate Tectonics SciPack explores the various materials that make up Earth and the processes they undergo to provide a framework for understanding how continents are created and change over time. The focus is on Standards and Benchmarks related to Earth's layers, oceanic and continental plates and the interactions between plates.In addition to comprehensive inquiry-based learning materials tied to Science Education Standards and Benchmarks, the SciPack includes the following additional components:� Pedagogical Implications section addressing common misconceptions, teaching resources and strand maps linking grade band appropriate content to standards. � Access to one-on-one support via e-mail to content "Wizards".� Final Assessment which can be used to certify mastery of the concepts.Learning Outcomes:Plate Tectonics: Layered Earth� Identify that Earth has layers (not necessarily name them), and that the interior is hotter and more dense than the crust.� Identify the crust as mechanically strong, and the underlying mantle as deformable and convecting.Plate Tectonics: Plates� Identify that the outermost layer of Earth is made up of separate plates.� Choose the correct speed of the motion of plates.� Identify the ocean floor as plate, in addition to the continents (to combat the common idea that only continents are plates, floating around on the oceans).� Recognize that oceans and continents can coexist on the same plate.Plate Tectonics: Plate Interactions� Identify the different interactions between plates.� Discuss what happens as a result of those interactions.Plate Tectonics: Consequences of Plate Interactions� Explain why volcanoes and earthquakes occur along plate boundaries. � Explain how new sea floor is created and destroyed.� Describe features that may be seen on the surface as a result of plate interactions.Plate Tectonics: Lines of Evidence� Use plate tectonics to explain changes in continents and their positions over geologic time.� Provide evidence for the idea of plates, including the location of earthquakes and volcanoes, continental drift, magnetic orientation of rocks in the ocean floor, etc.

National Science Teachers Association (NSTA)

2007-03-21

181

Technical note: enumeration of mesophilic aerobes in milk: evaluation of standard official protocols and petrifilm aerobic count plates  

Microsoft Academic Search

Enumeration of mesophilic aerobes (MA) is the main quality and hygiene parameter for raw and pasteur- ized milk. High levels of these microorganisms indicate poor conditions in production, storage, and processing of milk, and also the presence of pathogens. Fifteen raw and 15 pasteurized milk samples were submitted for MA enumeration by a conventional plating method (using plate count agar)

F. Carvalho

182

Parallel-plate resonator of variable spacer thickness for accurate measurements of surface impedance of highT{sub c} superconductive films  

Microsoft Academic Search

Measurements of microwave surface impedance of high-T{sub c} films at gigahertz frequencies and nitrogen temperature are performed. A simple technique employing a parallel-plate resonator with liquid nitrogen as a dielectric spaces is suggested. The use of a precise mechanical device provides smooth changing of distance between films from 200 μm down to zero. Coupling to the resonator is accomplished by

A. Y. Basovich; R. K. Belov; V. A. Markelov; L. A. Mazo; S. A. Pavlov; V. V. Talanov; A. V. Varganov

1992-01-01

183

Comparison of long-wavelength residual elevation and free air gravity anomalies in the North Atlantic and possible implications for the thickness of the lithospheric plate  

Microsoft Academic Search

For most oceans the basic feature of the elevation of ridges is a uniform relation between subsidence and age directly associated with the creation and cooling of the oceanic plate. In the North Atlantic we show that superimposed upon this subsidence curve are long-wavelength (>400-km) residual elevation anomalies up to 1200-m amplitude between 50°N and 10°N that are linearly related

John G. Sclater; Lawrence A. Lawver; Barry Parsons

1975-01-01

184

Casting/mold thermal contact heat transfer during solidification of Al-Cu-Si alloy (LM 21) plates in thick and thin molds  

NASA Astrophysics Data System (ADS)

Heat flow at the casting/mold interface was assessed and studied during solidification of Al-Cu-Si (LM 21) alloy in preheated cast iron molds of two different thicknesses, coated with graphite and alumina based dressings. The casting and the mold were instrumented with thermocouples connected to a computer controlled temperature data acquisition system. The thermal history at nodal locations in the mold and casting obtained during experimentation was used to estimate the heat flux by solving the one-dimensional inverse heat conduction problem. The cooling rate and solidification time were measured using the computer-aided cooling curve analysis data. The estimated heat flux transients showed a peak due to the formation of a stable solid shell, which has a higher thermal conductivity compared with the liquid metal in contact with the mold wall prior to the occurrence of the peak. The high values of heat flux transients obtained with thin molds were attributed to mold distortion due to thermal stresses. For thin molds, assumption of Newtonian heating yielded reliable interfacial heat transfer coefficients as compared with one-dimensional inverse modeling. The time of occurrence of peak heat flux increased with a decrease in the mold wall thickness and increase in the casting thickness.

Prabhu, K. Narayan; Chowdary, Bheemappa; Venkataraman, N.

2005-10-01

185

An investigation of surface reconstruction from binocular disparity based on standard regularization theory: comparison between "membrane" and "thin-plate" potential energy models.  

PubMed

Visible surfaces of three-dimensional objects are reconstructed from two-dimensional retinal images in the early stages of human visual processing. In the computational model of surface reconstruction based on the standard regularization theory, an energy function is minimized. Two types of model have been proposed, called "membrane" and "thin-plate" after their function formulas, in which the first or the second derivative of depth information is used. In this study, the threshold of surface reconstruction from binocular disparity was investigated using a sparse random dot stereogram, and the predictive accuracy of these models was evaluated. It was found that the thin-plate model reconstructed surfaces more accurately than the membrane model and showed good agreement with experimental results. The likelihood that these models imitate human processing of visual information is discussed in terms of the size of receptive fields in the visual pathways of the human cortex. PMID:21987913

Shiraiwa, Aya; Hayashi, Takefumi

2011-08-01

186

Plate Tectonics: Plate Interactions  

NSDL National Science Digital Library

This Science Object is the fourth of five Science Objects in the Plate Tectonic SciPack. It identifies the events that may occur and landscapes that form as a result of different plate interactions. The areas along plate margins are active. Plates pushing against one another can cause earthquakes, volcanoes, mountain formation, and very deep ocean trenches. Plates pulling apart from one another can cause smaller earthquakes, magma rising to the surface, volcanoes, and oceanic valleys and mountains from sea-floor spreading. Plates sliding past one another can cause earthquakes and rock deformation. Learning Outcomes:� Explain why volcanoes and earthquakes occur along plate boundaries. � Explain how new sea floor is created and destroyed.� Describe features that may be seen on the surface as a result of plate interactions.

National Science Teachers Association (NSTA)

2006-11-01

187

Plate Tectonics: Plates  

NSDL National Science Digital Library

This Science Object is the second of five Science Objects in the Plate Tectonics SciPack. It provides a conceptual understanding of what plates are and how they move, contributing to a constantly changing surface. The Earth's continents and ocean basins are made up of plates consisting of the crust and the upper part of the mantle. One plate can consist of both continental and oceanic crust. These plates move very slowly (an inch or so per year) on the hot, deformable layer of the mantle beneath them. The outward transfer of Earth's internal heat drives convection circulation in the mantle. This convection, together with gravitational pull on the plates themselves, causes the plates to move. Learning Outcomes:� Identify that the outermost layer of Earth is made up of separate plates.� Choose the correct speed of the motion of plates.� Identify the ocean floor as plate, in addition to the continents (to combat the common idea that only continents are plates, floating around on the oceans).� Recognize that oceans and continents can coexist on the same plate.

National Science Teachers Association (NSTA)

2006-11-01

188

Coracoid bone graft osteolysis after Latarjet procedure: A comparison study between two screws standard technique vs mini-plate fixation  

PubMed Central

Aims: One of the reason for Latarjet procedure failure may be coracoid graft osteolysis. In this study, we aimed to understand if a better compression between the coracoid process and the glenoid, using a mini-plate fixation during the Latarjet procedure, could reduce the amount of coracoid graft osteolysis. Materials and Methods: A computed tomography scan analysis of 26 prospectively followed-up patients was conducted after modified Latarjet procedure using mini-plate fixation technique to determine both the location and the amount of coracoid graft osteolysis in them. We then compared our current results with results from that of our previous study without using mini-plate fixation to determine if there is any statistical significant difference in terms of corcacoid bone graft osteolysis between the two surgical techniques. Results: The most relevant osteolysis was represented by the superficial part of the proximal coracoid, whereas the deep part of the proximal coracoid graft is least involved in osteolysis and has best bone healing. The current study showed a significant difference only for the deep part of the distal coracoid with our previous study (P < 0.01). Discussion: To our knowledge, there are no studies in literature that show the causes of coracoid bone graft osteolysis after Latarjet procedure. Conclusion: Our study suggests that there is a significant difference only for the deep part of the distal coracoid in terms of osteolysis. At clinical examination, this difference did not correspond with any clinical findings. Level of Evidence: Level 4. Clinical Relevance: Prospective case series, Treatment study.

Giacomo, Giovanni Di; Costantini, Alberto; de Gasperis, Nicola; De Vita, Andrea; Lin, Bernard K. H.; Francone, Marco; Beccaglia, Mario A. Rojas; Mastantuono, Marco

2013-01-01

189

Advantages of functional single-cell isolation method over standard agar plate dilution method as a tool for studying denitrifying bacteria in rice paddy soil  

PubMed Central

We recently established a method for isolating functional single cells from environmental samples using a micromanipulator (Functional single-cell (FSC) isolation), and applied it to the study of denitrifying bacteria in rice paddy soil (Ashida et al. 2010. Appl Microbiol Biotechnol 85:1211–1217). To further examine the advantages and possible disadvantages of the FSC method, we isolated denitrifying bacteria from the same rice paddy soil sample using both FSC and standard agar plate dilution (APD) methods and compared in this study. The proportion of denitrifying bacteria in the total isolates was more than 6-fold larger with FSC isolation (57.1%) compared with the APD method (9.2%). Denitrifying bacteria belonging to Alphaproteobacteria and Bacilli were commonly isolated using both methods, whereas those belonging to Betaproteobacteria, which had been found to be active in the denitrification-inductive paddy soil, were isolated only with the FSC method. On the other hand, Actinobacteria were only isolated using the APD method. The mean potential denitrification activity of the FSC isolates was higher than that of the APD isolates. Overall, FSC isolation was confirmed to be an excellent method for studying denitrifying bacteria compared with the standard agar plate dilution method.

2012-01-01

190

Advantages of functional single-cell isolation method over standard agar plate dilution method as a tool for studying denitrifying bacteria in rice paddy soil.  

PubMed

We recently established a method for isolating functional single cells from environmental samples using a micromanipulator (Functional single-cell (FSC) isolation), and applied it to the study of denitrifying bacteria in rice paddy soil (Ashida et al. 2010. Appl Microbiol Biotechnol 85:1211-1217). To further examine the advantages and possible disadvantages of the FSC method, we isolated denitrifying bacteria from the same rice paddy soil sample using both FSC and standard agar plate dilution (APD) methods and compared in this study. The proportion of denitrifying bacteria in the total isolates was more than 6-fold larger with FSC isolation (57.1%) compared with the APD method (9.2%). Denitrifying bacteria belonging to Alphaproteobacteria and Bacilli were commonly isolated using both methods, whereas those belonging to Betaproteobacteria, which had been found to be active in the denitrification-inductive paddy soil, were isolated only with the FSC method. On the other hand, Actinobacteria were only isolated using the APD method. The mean potential denitrification activity of the FSC isolates was higher than that of the APD isolates. Overall, FSC isolation was confirmed to be an excellent method for studying denitrifying bacteria compared with the standard agar plate dilution method. PMID:22985609

Nishizawa, Tomoyasu; Tago, Kanako; Uei, Yusuke; Ishii, Satoshi; Isobe, Kazuo; Otsuka, Shigeto; Senoo, Keishi

2012-09-18

191

Development of methods for estimating the Z properties of thick rolled products  

NASA Astrophysics Data System (ADS)

The main stages of developing the methods for estimating the mechanical properties of rolled plates across the plate thickness ( Z properties) and the corresponding standards are described in a chronological manner. The application of experimental fracture mechanics methods for estimating the sensitivity of building steels to laminated fracture is discussed. The effects of the structure dispersity, the steel purity in non-metallic inclusions, and the reduction on the Z properties of rolled products are described.

Odesskii, P. D.; Egorova, A. A.

2010-10-01

192

Standard Hardware and Corrosion: Pershing Problems and Action  

Microsoft Academic Search

During the Pershing reliability testing program, corrosion was encountered on standard mounting hardware. Investigation revealed an extremely low level of compliance of incoming hardware to the plating thickness requirements of military and Martin specifications. Most proposed solutions would have required extensive documentation changes or additional facilities. None of the approaches directly affected the actual cause of the problem: standard mounting

W. L. Chandler; D. E. Davis

1963-01-01

193

Bending of Plates at Suduction Zones: Estimates of the Plate Strength and Rheology from the Direction of Plate Motions  

Microsoft Academic Search

Cooling and subduction of the oceanic lithosphere is the primary source of buoyancy for convection in the mantle. However, the work required to bend the lithosphere penalizes subduction of cold, thick plates because bending has a strong dependence on plate thickness. The interplay between subduction and bending influences the direction of motion toward the trench, especially when the downgoing plate

B. A. Buffett; D. B. Rowley

2006-01-01

194

Magnetic Properties of Cobalt Plate Compared with Iron and Nickel Plates  

NASA Astrophysics Data System (ADS)

The magnetic behavior of Co plates has been compared with those of Fe and Ni plates studied in a previous work. It was found that the factor of magnetization ?b for Co plates does not show abrupt reduction with decreasing thickness, and magnetic flux density Bm and magnetization Pm are similar to those of Fe plates rather than Ni plates.

Tsunawaki, Yoshiaki; Ohigashi, Nobuhisa; Asakawa, Makoto R.

2012-02-01

195

Analysis of Sandwich Plates of Arbitrary Shape  

Microsoft Academic Search

A linear, static bending analysis of truss-core sandwich plates for arbitrary shape and boundary conditions is presented. The three-dimensional truss-core sandwich plate is idealized as an equivalent two-dimensional structurally orthotropic thick plate continuum. This analysis is based on the small deflection, first-order shear deformation theory of composite plates, which utilizes the Reissner–Mindlin plate theory. The behavior of the plate is

L. V. Kurpa; E. S. Ventsel

2005-01-01

196

Simulation of vibration of inhomogeneous, loaded plates  

Microsoft Academic Search

Summary The Timoshenko-Mindlin type wave equation is derived for a plate which is inhomogeneous in material and geometric properties. A numerical analogue to this wave equation for a plate is presented and results of propagation studies of Gaussian and sinusoidal wavepackets along a plate reinforced by ribs of up to five times the thickness of the plate are discussed. Results

B. C. H. Wendlandt; G. C. Gaunaurd

1994-01-01

197

A unified theory for laminated plates  

Microsoft Academic Search

A literature survey on plate and beam theories show how the advent of the finite element method and the variational method circa 1940 have been a great stimulant for the research in this field. The initial thin plate formulation has been incrementally expanded to treat the isotropic thick plate, the anisotropic single layer, and then laminated plates. It appears however

Irene Guiamatsia Tafeuvoukeng

2007-01-01

198

Comparative evaluation of the Rose Bengal plate test, standard tube agglutination test and complement fixation test for the diagnosis of human brucellosis.  

PubMed

In this study, 241 serum samples from individuals exposed to brucellosis were subjected to the Rose Bengal plate test (RBPT); the titre was estimated by standard tube agglutination test (STAT), with positive > or = 80 IU/ml. Randomly selected sera (n = 81) were analysed by complement fixation test (CFT): titre > or = 1:4 was considered positive. Of 241 sera subjected to RBPT and STAT, 177 were negative in both tests; 5 samples tested negative by RBPT but positive by STAT. None was positive by RBPT and negative by STAT. Of 81 sera subjected to CFT, 23 (28.4%) were positive. Both RBPT and CFT found 18 samples positive; 5 samples were positive by CFT and negative by RBPT. Comparison of STAT with CFT showed 13 samples positive by STAT but negative by CFT, and 4 positive by CFT but negative by STAT. The sensitivity and specificity of STAT were 82.6% and 77.6%, respectively, with CFT as gold standard. No test is perfect, and the clinical history coupled with a combination of two or more tests will reduce diagnostic errors. PMID:23520751

Yohannes, M; Gill, J P S; Ghatak, S; Singh, D K; Tolosa, T

2012-12-01

199

Dynamic Effects on Mechanical Characteristics of Composite Plates Submitted to Impact Tests  

Microsoft Academic Search

The present work deals with the behaviour of composite material plates submitted to impact loading conditions. The considered\\u000a composite material consists of long fibers in polymeric resin. Different stacking sequences and different plate thickness\\u000a are considered. Impact tests are performed according to the ASTM 3029 standard using our instrumented free-fall drop dart\\u000a testing machine, that allows to acquire the dart

G. Belingardi; M. P. Cavatorta; D. S. Paolino

200

Plate motion  

SciTech Connect

The motion of tectonic plates on the earth is characterized in a critical review of U.S. research from the period 1987-1990. Topics addressed include the NUVEL-1 global model of current plate motions, diffuse plate boundaries and the oceanic lithosphere, the relation between plate motions and distributed deformations, accelerations and the steadiness of plate motions, the distribution of current Pacific-North America motion across western North America and its margin, plate reconstructions and their uncertainties, hotspots, and plate dynamics. A comprehensive bibliography is provided. 126 refs.

Gordon, R.G. (USAF, Geophysics Laboratory, Hanscom AFB, MA (United States))

1991-01-01

201

Thermal Buckling of Functionally Graded Plates According to a Four-Variable Refined Plate Theory  

Microsoft Academic Search

In this article, a four-variable refined plate theory is presented for buckling analysis of functionally graded plates. The theory, which has strong similarity with classical plate theory in many aspects, accounts for a quadratic variation of the transverse shear strains across the thickness and satisfies the zero traction boundary conditions on the top and bottom surfaces of the plate without

Mohamed Bachir Bouiadjra; Mohammed Sid Ahmed Houari; Abdelouahed Tounsi

2012-01-01

202

Thermal buckling of functionally graded circular plates based on higher order shear deformation plate theory  

Microsoft Academic Search

In this research, thermal buckling of circular plates compose of functionally graded material (FGM) is considered. Equilibrium and stability equations of a FGM circular plate under thermal loads are derived, based on the higher order shear deformation plate theory (3rd order plate theory). Assuming that the material properties vary as a power form of the thickness coordinate variable z and

M. M. Najafizadeh; H. R. Heydari

2004-01-01

203

Plate Tectonics  

NSDL National Science Digital Library

Students will go over the main points of plate tectonics, including the theory of continental drift, different types of plate boundaries, seafloor spreading, and convection currents. We have been spending time learning about plate tectonics. We have discussed the theory of continental drift, we have talked about the different types of plate boundaries, we have also learned about seafloor spreading and convection currents. Plate Boundary Diagram Now is your chance ...

Rohlfing, Mrs.

2011-02-03

204

Finite element free vibration analysis of eccentrically stiffened plates  

Microsoft Academic Search

A new finite element model is proposed for free vibration analysis of eccentrically stiffened plates. The formulation allows the placement of any number of arbitrarily oriented stiffeners within a plate element without disturbing their individual properties. A plate-bending element consistent with the Reissner-Mindlin thick plate theory is employed to model the behaviour of the plating. A stiffener element, consistent with

T. P. Holopainen

1995-01-01

205

Plate Boundaries  

NSDL National Science Digital Library

This site provides information on plate boundaries, which are found at the edge of the lithospheric plates and are of three types: convergent, divergent and conservative. Wide zones of deformation are usually characteristic of plate boundaries because of the interaction between two plates. The three boundaries are characterized by their distinct motions which are described in the text and depicted with block diagram illustrations, all of which are animated. There are also two maps that show the direction of motion of the plates. Active links lead to more information on plate tectonics.

206

Plate Tectonics  

NSDL National Science Digital Library

In this activity students use data from underwater earthquakes to outline the location of plate boundaries. Data from the Northeast Pacific, eastern Equatorial Pacific, and North Atlantic are examined in more detail. Background information on plate tectonics is provided.

2002-01-01

207

Quantum levitation of a thin magnetodielectric plate on a metallic plate using the repulsive Casimir force  

NASA Astrophysics Data System (ADS)

Levitation of a thin magnetodielectric plate on a metallic plate by using the repulsive Casimir force is theoretically considered. If the permittivity of the metallic plate near zero frequency is expressed by a plasma model and the static permeability of the magnetodielectric plate is higher than its static permittivity, the Casimir force between the magnetodielectric plate and the metallic plate changes from attractive to repulsive as the separation between them increases. Furthermore, as the thickness of the magnetodielectric plate is decreased, the attractive component of the Casimir force decreases more than the repulsive one. This effect generates a larger repulsive Casimir force as compared with that between the plates having infinite thickness. Combined with the effect of decreasing the weight of the plate, this might enable a thin plate to levitate in vacuum. The height of quantum levitation is evaluated for a combination of yttrium iron garnet and gold.

Inui, Norio

2012-04-01

208

Free flexural vibrations of super elliptic plates  

Microsoft Academic Search

This paper deals with a direct problem of the free flexural vibrations of a plate with rounded corners on the basis of the theory of thin plates. The plate of uniform thickness is made of linear elastic, isotropic materials, and its periphery is given by a super elliptic function with a power. The super elliptic power defines the shape of

Murat Altekin; Gulay Altay; M. Cengiz Dokmeci

2001-01-01

209

Plate Tectonics  

NSDL National Science Digital Library

This interactive Flash explores plate tectonics and provides an interactive map where users can identify plate boundaries with name and velocities as well as locations of earthquakes, volcanoes, and hotspots. The site also provides animations and supplementary information about plate movement and subduction. This resource is a helpful overview or review for introductory level high school or undergraduate physical geology or Earth science students.

Smoothstone; Company, Houghton M.

210

Plate Tectonics  

NSDL National Science Digital Library

Create a poster all about Plate Tectonics! Directions: Make a poster about Plate Tectonics. (20 points) Include at least (1) large picture (15 points) on your poster complete with labels of every part (10 points). (15 points) Include at least three (3) facts about Plate Tectonics. (5 points ...

Walls, Mrs.

2011-01-30

211

Plate perforation by eroding rod projectiles  

Microsoft Academic Search

The penetration and perforation of stationary, oblique steel plates by hypervelocity tungsten-alloy projectiles is examined here. Simulations have been performed for L\\/D 10 projectiles against one- and two-plate target configurations. The plate thickness-to-rod diameter ratio t\\/D varied slightly, as did the plate spacing-to-plate thickness ratio tgap\\/t. For all simulations, t\\/D?[1.2,1.6] and tgap\\/t?[0.7,1]. Normalized line-of-sight perforation is one measure of performance,

D. J. Gee

2003-01-01

212

Thick DGP braneworlds  

SciTech Connect

We study Dvali-Gabadadze-Porrati (DGP) braneworlds with finite thickness. In respect to the standard (thin) DGP Friedmann equation, finite thickness of the brane causes a subtle modification of the cosmological equations that can lead to significant physical consequences. The resulting cosmology is governed by two length scales which are associated with the brane thickness and with the crossover length, respectively. In this setup both early inflation and late-time acceleration of the expansion are a consequence of the 5D geometry. At early times, as well as at late times, 5D effects become dominant (gravity leaks into the extra dimension), while, at intermediate times, gravity is effectively 4D due to nontrivial physics occurring in standard (thin) DGP scenarios.

Quiros, Israel [Departamento de Fisica, Universidad Central de Las Villas, 54830 Santa Clara (Cuba); Matos, Tonatiuh [Departamento de Fisica, Centro de Investigacion y de Estudios Avanzados del IPN, A.P. 14-740, 07000 Mexico D.F. (Mexico)

2008-11-15

213

NICKEL PLATING PROCESS  

DOEpatents

A simplified process is presented for plating nickel by the vapor decomposition of nickel carbonyl. In a preferred form of the invention a solid surface is nickel plated by subjecting the surface to contact with a mixture containing by volume approximately 20% nickel carbonyl vapor, 2% hydrogen sulfide and .l% water vapor or 1% oxygen and the remainder carbon dioxide at room temperature until the desired thickness of nickel is obtained. The advantage of this composition over others is that the normally explosive nickel carbonyl is greatly stabilized.

Hoover, T.B.; Zava, T.E.

1959-05-12

214

Pixelated neutron image plates  

NASA Astrophysics Data System (ADS)

Neutron image plates (NIPs) have found widespread application as neutron detectors for single-crystal and powder diffraction, small-angle scattering and tomography. After neutron exposure, the image plate can be read out by scanning with a laser. Commercially available NIPs consist of a powder mixture of BaFBr : Eu2+ and Gd2O3 dispersed in a polymer matrix and supported by a flexible polymer sheet. Since BaFBr : Eu2+ is an excellent x-ray storage phosphor, these NIPs are particularly sensitive to ggr-radiation, which is always present as a background radiation in neutron experiments. In this work we present results on NIPs consisting of KCl : Eu2+ and LiF that were fabricated into ceramic image plates in which the alkali halides act as a self-supporting matrix without the necessity for using a polymeric binder. An advantage of this type of NIP is the significantly reduced ggr-sensitivity. However, the much lower neutron absorption cross section of LiF compared with Gd2O3 demands a thicker image plate for obtaining comparable neutron absorption. The greater thickness of the NIP inevitably leads to a loss in spatial resolution of the image plate. However, this reduction in resolution can be restricted by a novel image plate concept in which a ceramic structure with square cells (referred to as a 'honeycomb') is embedded in the NIP, resulting in a pixelated image plate. In such a NIP the read-out light is confined to the particular illuminated pixel, decoupling the spatial resolution from the optical properties of the image plate material and morphology. In this work, a comparison of experimentally determined and simulated spatial resolutions of pixelated and unstructured image plates for a fixed read-out laser intensity is presented, as well as simulations of the properties of these NIPs at higher laser powers.

Schlapp, M.; Conrad, H.; von Seggern, H.

2004-09-01

215

Ballistic Limit of CFRP Plates  

NASA Astrophysics Data System (ADS)

JAXA has carried out the hypervelocity impact tests of carbon fiber reinforced plastic (CFRP) plates together with University of Padova. Quasi-isotropic CFRP plates of 2.3, 3.5, and 4.7 mm in thickness were tested. Aluminum sphere of 0.8 to 2.9 mm in diameter was used as projectiles. With a two-stage light gas gun, the projectile was launched with a velocity range of 2 to 5 km/sec in the normal direction to the CFRP plate. Since the perforated hole and the crater on the CFRP plate after the impact are filled with flakes of the carbon fiber, it is difficult to determine the perforation of the projectile. Therefore, whether the projectile perforated the CFRP plate or not was decided by the craters on a copper plate installed behind the CFRP plate. After the impact, peeling along the fiber direction was observed on the surface of the CFRP plate. Moreover, internal delamination was generated near the surface. Finally, a ballistic limit equation of CFRP plates of 2 to 5 mm in thickness was calculated on the basis of the Cour-Palais equation. The ballistic limit equation was in good agreement with the test results.

Higashide, Masumi; Nagao, Yosuke; Kibe, Seishiro; Francesconi, Alessandro; Pavarin, Daniele

216

Plate subrotations  

NASA Astrophysics Data System (ADS)

The kinematics of plates is defined by Euler pole and angular velocity. However, during their journey, plates may be affected by additional simultaneous rotations (i.e., subrotations) while they are rotating about their Euler poles. The kinematic description of this particular plate motion requires a different analytical approach: two angular velocities and two poles are necessary to completely describe plate displacements. If a subrotation occurs, none of the points on a plate moves along circles of the Euler pole but, instead, follows cycloid trajectories because of the combination of the two simultaneous rotations. Regardless of the forces that move the lithosphere, every time a plate experiences a subrotation, an additional force (or resisting) force could act on the plate, generating the two-rotation motion. In the hot spot reference frame, we applied this model to the North America plate, investigating its past motion for a time interval ?t = 43 Ma up to the present and comparing results with those obtained by Gordon and Jurdy (1986). This application shows how the different positions of the North America plate over most of the Cenozoic can be reconstructed by two-rotation plate kinematics.

Cuffaro, Marco; Caputo, Michele; Doglioni, Carlo

2008-08-01

217

Consecutive plate acoustic suppressor apparatus and methods  

NASA Astrophysics Data System (ADS)

An apparatus and method for suppressing acoustic noise utilizes consecutive plates, closely spaced to each other so as to exploit dissipation associated with sound propagation in narrow channels to optimize the acoustic resistance at a liner surface. The closely spaced plates can be utilized as high temperature structural materials for jet engines by constructing the plates from composite materials. Geometries of the plates, such as plate depth, shape, thickness, inter-plate spacing, arrangement, etc., can be selected to achieve bulk material-like behavior.

Doychak, Joseph; Parrott, Tony

1992-10-01

218

Accurate formula for determination of natural frequencies of FGM plates basing on frequencies of isotropic plates  

Microsoft Academic Search

The functionally graded materials (FGM) have many advantages especially in thermal environments, and in the recent years they have been used in many engineering applications. A FGM plate is an inhomogeneous composite made of two constituents (usually ceramic and metal), with both the composition and the material properties varying smoothly through the thickness of the plate. The FGM plate vibrations

Elia Efraim

2011-01-01

219

Stiffness and strength design of composite bone plates  

Microsoft Academic Search

Although the potential of composites used for bone plate implantation has been realized for a long period of time, not much literature has addressed optimal design of composite bone plates upon variation in reinforcing fiber structures, plate thicknesses, and so on. In this paper, we present a preliminary but critical design procedure for composite bone plate with target on both

Zheng-Ming Huang; K. Fujihara

2005-01-01

220

Plastic Analysis and Design of Steel Plate Shear Walls  

Microsoft Academic Search

Summary A revised procedure for the design of steel plate shear walls is proposed. In this procedure, the thickness of the infill plate is found using equations that are derived from plastic analysis of the strip model, which is widely accepted for the representation of steel plate shear walls. Equations are derived from a basic steel plate shear wall configuration

Jeffrey Berman; Michel Bruneau

2003-01-01

221

Plate Tectonics  

NSDL National Science Digital Library

This site contains 25 questions on the topic of plate tectonics, which covers the development of the theory, crustal movements, geologic features associated with tectonics, and plate boundaries (convergent, divergent, transform). This is part of the Principles of Earth Science course at the University of South Dakota. Users submit their answers and are provided immediate verification.

Heaton, Timothy

222

Statistical tests of additional plate boundaries from plate motion inversions  

Microsoft Academic Search

The application of the F-ratio test, a standard statistical technique, to the results of relative plate motion inversions has been investigated. The method tests whether the improvement in fit of the model to the data resulting from the addition of another plate to the model is greater than that expected purely by chance. This approach appears to be useful in

Seth Stein; R. G. Gordon

1984-01-01

223

Ballistic Limit of CFRP Plates  

Microsoft Academic Search

JAXA has carried out the hypervelocity impact tests of carbon fiber reinforced plastic (CFRP) plates together with University of Padova. Quasi-isotropic CFRP plates of 2.3, 3.5, and 4.7 mm in thickness were tested. Aluminum sphere of 0.8 to 2.9 mm in diameter was used as projectiles. With a two-stage light gas gun, the projectile was launched with a velocity range

Masumi Higashide; Yosuke Nagao; Seishiro Kibe; Alessandro Francesconi; Daniele Pavarin

2009-01-01

224

Effective elastic thickness and crustal thickness variations in west central Africa inferred from gravity data  

SciTech Connect

This report uses coherence function analysis of 32,000 gravity and topography points from Cameroon west Africa to determine the relationship between the plate tectonic and flexural rigidity of the lithosphere in terms of the crusts effective elastic thickness.

Poudjom Djomani, Y.H.; Nnange, J.M.; Ebinger, C.J. [Univ. of Leeds (United Kingdom)] [and others

1995-11-10

225

Microstructure of explosively loaded 304 stainless steel flyer plate  

Microsoft Academic Search

A 304 SS flyer plate 0.54 cm thick was driven at 25 GPa at 2 ..mu..sec pulse duration. A figure illustrates the increase in hardness through the plate thickness. The higher hardness occurs at the bottom of the flyer plate. Stain-induced ..cap alpha..'-martensite morphology was obtained in the 304 specimen, just below the flyer plate from the same impact. The

K. A. Johnson; K. P. Staudhammer; L. E. Murr

1982-01-01

226

Factors Affecting Energy Absorption of a Plate during Shock Wave Impact Using a Damage Material Model.  

National Technical Information Service (NTIS)

This thesis examines the influences of five factors on the strain energy at failure of metallic alloy plates during a shock wave impact. The five factors are material type, initial damage, boundary conditions, plate thickness, and plate temperature. The f...

Z. K. Crosby

2010-01-01

227

Strength of Longitudinally Stiffened Plate Panels with Large B/T.  

National Technical Information Service (NTIS)

An analytical investigation of the ultimate strength of longitudinally stiffened plate panels having large plate width to thickness ratios (plate buckles before the ultimate axial strength of panel is reached), and subjected to combined axial and uniforml...

T. Tsuiji

1965-01-01

228

Effect of Curvature on the Impact Damage Characteristics and Residual Strength of Composite Plates.  

National Technical Information Service (NTIS)

The results of a study of the response and failure characteristics of thin, cylindrically curved, composite plates subjected to low-speed impact damage are presented. The results indicate that the plate radius and the plate thickness are important structu...

D. R. Ambur J. H. Starnes

1998-01-01

229

Character-based car plate detection and localization  

Microsoft Academic Search

In this paper we address the issue of locating non-standard Malaysian car license plate. Instead of searching the region for the plate, we directly locate the alphanumeric characters of the car plate. In this manner, we remove issues such as plate size variations and plates on black colored vehicles. Our main goal is to locate and extract the alphanumeric characters

S. Setumin; U. U. Sheikh; S. A. R. Abu-Bakar

2010-01-01

230

Plate Motions  

NSDL National Science Digital Library

To prepare for this exercise students read the Chapter on plate tectonics in their text book. In class, they are given a color isochron map of the sea floor. They are given 4 tasks: Answer basic questions about the timing and rate of opening of the N. and S. Atlantic; Determine what has happened to the oceanic crust that is created on the eastern side of the East Pacific Rise; Determine what type of plate boundary existed on the western edge of the N. America plate before the San Andreas Fault and when this transition occurred; and Reconstruct the motion of the plates over the last 40 Ma assuming that the surface area of the Earth has not changed.

Nunn, Jeffrey

231

Plate Tectonics  

NSDL National Science Digital Library

Plate tectonic activity is being observed presently on a historic timescale, especially in the form of volcanic eruptions and earthquakes, but, as with many large-scale Earth science phenomena, it is hard to ...

232

Effects on Intact Femora of Dogs of the Application and Removal of Metal Plates A METABOLIC AND STRUCTURAL STUDY COMPARING STIFFER AND MORE FLEXIBLE PLATES  

Microsoft Academic Search

Studies of flexible plates made of plastic have shown that less osteoporosis develops beneath them than beneath rigid metal plates. However, to date plastic plates of appropriate physical properties and biocompatibility are not available for use in humans. To determine if a similar beneficial effect could be ob- tamed using metal plates, the effects of thick chromium cobalt plates were

BERNARD J. L. MOYEN; PHILIP J. LAHEY; EDITH H. WEINBERG; WILLIAM H. HARRIS

233

Reliability assessment of different plate theories for elastic wave propagation analysis in functionally graded plates.  

PubMed

The importance of elastic wave propagation problem in plates arises from the application of ultrasonic elastic waves in non-destructive evaluation of plate-like structures. However, precise study and analysis of acoustic guided waves especially in non-homogeneous waveguides such as functionally graded plates are so complicated that exact elastodynamic methods are rarely employed in practical applications. Thus, the simple approximate plate theories have attracted much interest for the calculation of wave fields in FGM plates. Therefore, in the current research, the classical plate theory (CPT), first-order shear deformation theory (FSDT) and third-order shear deformation theory (TSDT) are used to obtain the transient responses of flexural waves in FGM plates subjected to transverse impulsive loadings. Moreover, comparing the results with those based on a well recognized hybrid numerical method (HNM), we examine the accuracy of the plate theories for several plates of various thicknesses under excitations of different frequencies. The material properties of the plate are assumed to vary across the plate thickness according to a simple power-law distribution in terms of volume fractions of constituents. In all analyses, spatial Fourier transform together with modal analysis are applied to compute displacement responses of the plates. A comparison of the results demonstrates the reliability ranges of the approximate plate theories for elastic wave propagation analysis in FGM plates. Furthermore, based on various examples, it is shown that whenever the plate theories are used within the appropriate ranges of plate thickness and frequency content, solution process in wave number-time domain based on modal analysis approach is not only sufficient but also efficient for finding the transient waveforms in FGM plates. PMID:23714123

Mehrkash, Milad; Azhari, Mojtaba; Mirdamadi, Hamid Reza

2013-05-09

234

The Bending and Stretching of Plates  

NASA Astrophysics Data System (ADS)

Written by one of the world's leading authorities on plate behavior, this study gives a clear physical insight into elastic plate behavior. Small-deflection theory is treated in Part 1 in chapters dealing with basic equations: including thermal effects and multi-layered anisotropic plates, rectangular plates, circular and other shaped plates, plates whose boundaries are amenable to conformal transformation, plates with variable thickness, and approximate methods. Large-deflection theory is treated in Part 2 in chapters dealing with basic equations and exact solutions; approximate methods, including post-buckling behavior; and asymptotic theories for very thin plates, including tension field theory and inextensional theory. The mathematical content is necessarily high, making the style of the book appropriate to engineers and applied mathematicians. E.H. Mansfield is a Fellow of the Royal Society, a founder member of the Fellowship of Engineering, and the author of over 100 publications.

Mansfield, Eric Harold

1989-09-01

235

The Bending and Stretching of Plates  

NASA Astrophysics Data System (ADS)

Written by one of the world's leading authorities on plate behavior, this study gives a clear physical insight into elastic plate behavior. Small-deflection theory is treated in Part 1 in chapters dealing with basic equations: including thermal effects and multi-layered anisotropic plates, rectangular plates, circular and other shaped plates, plates whose boundaries are amenable to conformal transformation, plates with variable thickness, and approximate methods. Large-deflection theory is treated in Part 2 in chapters dealing with basic equations and exact solutions; approximate methods, including post-buckling behavior; and asymptotic theories for very thin plates, including tension field theory and inextensional theory. The mathematical content is necessarily high, making the style of the book appropriate to engineers and applied mathematicians. E.H. Mansfield is a Fellow of the Royal Society, a founder member of the Fellowship of Engineering, and the author of over 100 publications.

Mansfield, Eric Harold

2005-08-01

236

Electric Current Analysis for Thick Laminated CFRP Composites  

NASA Astrophysics Data System (ADS)

This paper deals with a new lamination theory to calculate the electric current density on carbon fiber reinforced plastic (CFRP) laminates. Unidirectional CFRP has strong orthotropic electric conductance. When electric current is applied to the surface of a CFRP plate, the electric voltage field is not uniform in the thickness direction for thick CFRP. The electric current concentrates near the surface where the electric current is applied to thick CFRP laminates. In this study, a new lamination theory for thick CFRP laminates is proposed. The theory for thick CFRP assumes a non-uniform electric voltage distribution in the thickness direction. For non-thick and non-thin CFRP plates, an approximation method is proposed. To obtain the shape of the non-uniform voltage distribution, the analytical results of thick unidirectional ply from a previous paper is adopted as a contribution function to calculate the effective conductance of the thick CFRP laminate. Cross-sectional two-dimensional (2D) FEM analysis is used to obtain the contribution function for the non-thick CFRP plate. The proposed methods are applied to two cases of the thick CFRP plates, and the results are compared with the three-dimensional (3D) FEM results. Consequently, the new lamination theory is shown to be very effective for the CFRP plates.

Todoroki, Akira

237

Gas tungsten arc welding procedures for tantalum alloy T-111 (Ta8W--2Hf) plate. Final report, 1971--1972  

Microsoft Academic Search

Methods of eliminating or reducing underbred cracking in multipass GTA ; welds in thick T-111 plate were studied. Single-V butt welds prepared using ; experimental filler metal compositions and standard weld procedures resulted in ; only moderate success in reducing underbred cracking. Subsequent procedural ; changes incorporating manual welding, slower weld speeds, and three or fewer fill ; passes resulted

R. E. Gold; R. L. Kesterson

1973-01-01

238

An understanding of HSLA-65 plate steels  

NASA Astrophysics Data System (ADS)

HSLA-65 plate steels can be produced using one of five plate manufacturing techniques: normalizing, controlled rolling (CR), controlled rolling followed by accelerated cooling (CR-AC), direct quenching and tempering (DQT), or conventional quenching and tempering (Q&T). The HSLA-65 steels are characterized by low carbon content and low alloy content, and they exhibit a low carbon equivalent that allows improved plate weldability. These characteristics in turn (a) provide the steel plate with a refined microstructure that ensures high strength and toughness; (b) eliminate or substantially reduce the need for preheating during welding; (c) resist susceptibility to hydrogen-assisted cracking (HAC) in the weld heat affected zone (HAZ) when fusion (arc) welded using low heat-input conditions; and (d) depending on section thickness, facilitate high heat-input welding (about 2 kJ/mm) without significant loss of strength or toughness in the HAZ. However, application of this plate manufacturing process and of these controls produces significant differences in the metallurgical structure and range of mechanical properties of the HSLA-65 plate steels both among themselves and versus conventional higher strength steel (HSS) plates. For example, among the HSLA-65 plate steels, those produced by Q&T exhibit minimal variability in mechanical properties, especially in thicker plates. Besides variability in mechanical properties depending on plate thickness, the CR and CR-AC plate steels exhibit a relatively higher yield strength to ultimate tensile strength (YS/UTS) ratio than do DQT and Q&T steels. Such differences in processing and properties of HSLA-65 plate steels could potentially affect the selection and control of various secondary fabrication practices, including arc welding. Consequently, fabricators must exercise extreme caution when transferring allowable limits of certified secondary fabrication practices from one type of HSLA-65 plate steel to another, even for the same plate thickness.

Sampath, K.

2006-02-01

239

Optical Analyzer Technique for Spall Investigations in Metal Plates  

SciTech Connect

Possible experimental set-up for investigation of the stage of spalls closing in plates before impact on base plate are considered. Multi-wave configurations in indicator-matter situated on the base plate are observed by optical analyzer technique. Oscillograms and results of their processing are presented. Thickness and average density of the spall layer in the plate immediately before its impact on the base plate are estimated.

Kovalenko, G. V.; Kozlov, E. A.; Nogin, V. N.; Pankratov, D. G.; Yakunin, A. K. [Federal State Unitary Enterprise 'Russian Federal Nuclear Center - Zababakhin All-Russia Research Institute of Technical Physics', 456770, Snezhinsk, Chelyabinsk region (Russian Federation)

2006-08-03

240

Tensile Work Hardening Behavior of Thin-Section Plate and Thick-Section Tubeplate Forging of 9Cr-1Mo Steel in the Framework of One-Internal-Variable Kocks-Mecking Approach  

NASA Astrophysics Data System (ADS)

Comparative tensile flow and work hardening behavior of normalized and tempered plate and quenched and tempered tubeplate forgings of 9Cr-1Mo steel have been examined in the framework of one-internal-variable Kocks-Mecking approach at temperatures ranging from 300 K to 873 K (27 °C to 600 °C). Detailed analysis in terms of the variations of instantaneous work hardening rate, ? ( ? = d ?/d ? p = d ? p/d ? p, where ? is the true stress, ? p is the plastic flow stress component, and ? p is the true plastic strain) with ? and ? p indicated two-stage work hardening behavior, and three distinct temperature regimes in the variations of work hardening parameters, ? - ? and ? - ? p, with temperature. The influence of initial microstructures associated with different product forms of the steel is reflected in the systematic variations in work hardening parameters at temperatures ranging from 300 K to 873 K (27 °C to 600 °C). Tubeplate forging exhibited improved work hardening characteristics in terms of higher plastic component of flow stress because of microstructural softening than that of the plate material in the steel.

Choudhary, B. K.; Christopher, J.

2013-11-01

241

Inelastic buckling of plate  

NASA Astrophysics Data System (ADS)

This paper concerns the inelastic stability of a thin plate under in-plane loading. In Love-Kirchhoffs approximation, using Hencky's relations and the Von Mises criterion, yield the particular stress distribution across the plate thickness for elastic and elastic-plastic prestress fields. The principle of virtual work is used to study the equilibrium of the bifurcated solution. This leads to the energy relations where explicit dependence between the stability equation coefficients and the solution is carried out. In the equilibrium equation, two nonquadratic additional terms are obtained which are neglected in the classical equation. Some applications are made using Ramberg-Osgood's formula to show the importance of the additional terms.

Rio, G.

242

Theory of the parallel plate viscometer  

Microsoft Academic Search

The theoretical treatment for the rate of approach of two parallel circular plates separated by a viscous liquid is subject to the limiting condition that the separation of the plates must be small compared to the test-piece radius. The theory is extended to apply to test-pieces of any thickness and the modified treatment is shown to be in accord with

A N Gent

1960-01-01

243

Broadband omnidirectional metal-plate monopole antenna  

Microsoft Academic Search

A novel broad-band omnidirectional metal-plate monopole antenna is presented. The proposed antenna is a step-shaped metal-plate monopole, which is easily fabricated from bending a metal plate (a 0.2 mm thick brass sheet used in this study). The proposed antenna shows improved omnidirectional radiation for frequencies across a very wide operating bandwidth (frequency ratio about 1:3), compared to a corresponding planar

Kin-Lu Wong; Saou-Wen Su; Chia-Lun Tang

2005-01-01

244

Martian plate tectonics  

NASA Astrophysics Data System (ADS)

The northern lowlands of Mars have been produced by plate tectonics. Preexisting old thick highland crust was subducted, while seafloor spreading produced thin lowland crust during late Noachian and Early Hesperian time. In the preferred reconstruction, a breakup margin extended north of Cimmeria Terra between Daedalia Planum and Isidis Planitia where the highland-lowland transition is relatively simple. South dipping subduction occured beneath Arabia Terra and east dipping subduction beneath Tharsis Montes and Tempe Terra. Lineations associated with Gordii Dorsum are attributed to ridge-parallel structures, while Phelegra Montes and Scandia Colles are interpreted as transfer-parallel structures or ridge-fault-fault triple junction tracks. Other than for these few features, there is little topographic roughness in the lowlands. Seafloor spreading, if it occurred, must have been relatively rapid. Quantitative estimates of spreading rate are obtained by considering the physics of seafloor spreading in the lower (approx. 0.4 g) gravity of Mars, the absence of vertical scarps from age differences across fracture zones, and the smooth axial topography. Crustal thickness at a given potential temperature in the mantle source region scales inversely with gravity. Thus, the velocity of the rough-smooth transition for axial topography also scales inversely with gravity. Plate reorganizations where young crust becomes difficult to subduct are another constraint on spreading age. Plate tectonics, if it occurred, dominated the thermal and stress history of the planet. A geochemical implication is that the lower gravity of Mars allows deeper hydrothermal circulation through cracks and hence more hydration of oceanic crust so that more water is easily subducted than on the Earth. Age and structural relationships from photogeology as well as median wavelength gravity anomalies across the now dead breakup and subduction margins are the data most likely to test and modify hypotheses about Mars plate tectonics.

Sleep, N. H.

1994-03-01

245

Sensitivity, Specificity, and Predictive Values of Three Salmonella Rapid Detection Kits Using Fresh and Frozen Poultry Environmental Samples versus Those of Standard Plating  

Microsoft Academic Search

To reduce human exposure to Salmonella spp. in poultry products, broiler chicken flocks have been tested by culture methods. Since the standard techniques may take 3 to 5 days, rapid detection methods have been developed. In this study we tested the performance of three rapid tests originally developed for food samples by using environmental samples obtained from poultry houses. These

MELISSA O. PEPLOW; MARIA CORREA-PRISANT; MARTHA E. STEBBINS

1999-01-01

246

Musical Plates: A Study of Plate Tectonics  

NSDL National Science Digital Library

In this project, students use Real-Time earthquake and volcano data from the Internet to explore the relationship between earthquakes, plate tectonics, and volcanoes. There is a teachers guide that explains how to use real time data, and in the same section, there is a section for curriculum standards, Supplement and enrichment activities, and assessment suggestions. Included on this webpage are four core activities, and three enrichment activities, including an activity where the student writes a letter to the president. There is also a link to reference materials that might also interest you and your students.

2007-01-01

247

Trapped energy quartz crystal resonator on wedge-shaped plate  

Microsoft Academic Search

Based upon the general relation of dispersion for a quartz plate of doubly rotated cut, an analytical model is presented. It describes the modes shapes of a resonator exhibiting a linear thickness variation along in-plane directions and is only submitted to the following assumptions: small wave numbers along the plate plane and slowly varying thickness. The proposed model allows a

R. Bourquin

1992-01-01

248

Selective nickel and gold plating for enhanced wire bonding technology  

Microsoft Academic Search

Nickel and gold are electrodeposited on wire bond pads by a newly developed selective plating process in which plating is done without photoresist. The gold terminal metal offers exciting advantage over the traditional aluminum metallurgy. The unique self-encapsulating structure of gold and nickel over copper seed is illustrated. The plating tool, process control and thickness uniformity are described. We have

Tien Cheng; Kevin Petrarca; Kamalesh Srivastava; Sarah Knickerbocker; Richard Volant; Wolfgang Sauter; Samuel McKnight; Stephanie Allard; Frederic Beaulieu; Darryl Restaino; Takashi Hisada

2006-01-01

249

Wave propagation in and sound transmission through sandwich plates  

Microsoft Academic Search

Some dynamical and acoustical properties of sandwich plates are investigated. The types of sandwich elements discussed are three-layered plates with a thick lightweight core, with thin and comparatively stiff laminates bonded to each side of the core. In the model derived it is assumed that the laminates and core are isotropic. The laminates are treated as thin plates, whereas the

A. C. Nilsson

1990-01-01

250

NONLINEAR MAGNETOTHERMOELASTICITY OF ANISOTROPIC PLATES IMMERSED IN A MAGNETIC FIELD  

Microsoft Academic Search

A geometrically nonlinear theory of magnetothermoelasticity of electroconductive anisotropic plates in a magnetic field is developed. In this context, the Kirchhoff hypothesis is adopted for the plate modeling and the geometrical nonlinearities are considered in the von Kármán sense. In addition, the assumptions related to the distribution of electric and magnetic field disturbances through the plate thickness as proposed by

Liviu Librescu; Davresh Hasanyan; Zhanming Qin; Damodar R. Ambur

2003-01-01

251

Bone plate  

US Patent & Trademark Office Database

A bone plate assembly and method of use comprising a head; a shaft; an upper surface; a lower surface having a fixed plane intended to be adjacent to the patient's bone when the plate is in use; a first hole positioned in the head wherein the first hole passes through the upper and lower surfaces and is configured to fix a shaft of a first bone anchor along a first axis; a second hole positioned on the anterior portion of the upper surface of the head wherein the second hole passes through the upper and lower surfaces and is configured to fix a shaft of a second bone anchor along a second axis; and a third hole positioned in the posterior side of the head wherein the third hole passes through the upper and lower surfaces and is configured to fix a shaft of a third bone anchor along a third axis, wherein the first axis, the second axis and the third axis do not intersect in the bone when the plate is in use.

Gehlert; Rick J. (Albuquerque, NM)

2012-09-18

252

Experiments on the turbulent boundary layer on a flat plate in the wake of another flat plate  

Microsoft Academic Search

Experiments were conducted on the development of the turbulent boundary layer on a flat plate which was located in the wake of another flat plate. The investigation covered six cases in which the distance between the plates and the momentum thickness of the upstream wake were varied. The results show that the mean velocity and longitudinal fluctuation in the outer

S. Sundaram; K. S. Yajnik

1990-01-01

253

Dynamics of subduction and plate motion in laboratory experiments: Insights into the ``plate tectonics'' behavior of the Earth  

Microsoft Academic Search

Three-dimensional laboratory experiments have been designed to investigate the way slab-bearing plates move during subduction inside the mantle. In our experiments a viscous plate of silicone (lithosphere) subducts under its negative buoyancy in a viscous layer of pure honey (mantle). Varying thickness, width, viscosity, and density of the plate and mantle, three characteristic modes of subduction are observed: a retreating

Nicolas Bellahsen; Claudio Faccenna; Francesca Funiciello

2005-01-01

254

Tube wall thickness measurement apparatus  

DOEpatents

An apparatus for measuring the thickness of a tube's wall for the tube's entire length and radius by determining the deviation of the tube wall thickness from the known thickness of a selected standard item. The apparatus comprises a base and a first support member having first and second ends. The first end is connected to the base and the second end is connected to a spherical element. A second support member is connected to the base and spaced apart from the first support member. A positioning element is connected to and movable relative to the second support member. An indicator is connected to the positioning element and is movable to a location proximate the spherical element. The indicator includes a contact ball for first contacting the selected standard item and holding it against the spherical element. The contact ball then contacts the tube when the tube is disposed about the spherical element. The indicator includes a dial having a rotatable needle for indicating the deviation of the tube wall thickness from the thickness of the selected standard item.

Lagasse, P.R.

1985-06-21

255

Tectonic Plates and Plate Boundaries  

NSDL National Science Digital Library

Continents were once thought to be static, locked tight in their positions in Earth's crust. Similarities between distant coastlines, such as those on opposite sides of the Atlantic, were thought to be the work of a scientist's overactive imagination, or, if real, the result of erosion on a massive scale. This interactive feature shows 11 tectonic plates and their names, the continents that occupy them, and the types of boundaries between them.

2011-05-09

256

Tectonic Plates and Plate Boundaries  

NSDL National Science Digital Library

Continents were once thought to be static, locked tight in their positions in Earth's crust. Similarities between distant coastlines, such as those on opposite sides of the Atlantic, were thought to be the work of a scientist's overactive imagination, or, if real, the result of erosion on a massive scale. This interactive feature shows 11 tectonic plates and their names, the continents that occupy them, and the types of boundaries between them.

257

How to optimize the drop plate method for enumerating bacteria.  

PubMed

The drop plate (DP) method can be used to determine the number of viable suspended bacteria in a known beaker volume. The drop plate method has some advantages over the spread plate (SP) method. Less time and effort are required to dispense the drops onto an agar plate than to spread an equivalent total sample volume into the agar. By distributing the sample in drops, colony counting can be done faster and perhaps more accurately. Even though it has been present in the laboratory for many years, the drop plate method has not been standardized. Some technicians use 10-fold dilutions, others use twofold. Some technicians plate a total volume of 0.1 ml, others plate 0.2 ml. The optimal combination of such factors would be useful to know when performing the drop plate method. This investigation was conducted to determine (i) the standard deviation of the bacterial density estimate, (ii) the cost of performing the drop plate procedure, (iii) the optimal drop plate design, and (iv) the advantages of the drop plate method in comparison to the standard spread plate method. The optimal design is the combination of factor settings that achieves the smallest standard deviation for a fixed cost. Computer simulation techniques and regression analysis were used to express the standard deviation as a function of the beaker volume, dilution factor, and volume plated. The standard deviation expression is also applicable to the spread plate method. PMID:11165341

Herigstad, B; Hamilton, M; Heersink, J

2001-03-01

258

Performance study of braided carbon/PEEK composite compression bone plates.  

PubMed

In addition to unidirectional laminates and short fiber reinforcements for compression bone plate developments in the literature, we have proposed using a textile structure, i.e. braid preform, for this purpose. In the present paper, the influence of braiding angles and plate thicknesses on the bending performance of the braided composite bone plates is investigated. As a result, the influence of the braiding angle, varied in a certain range, on the plate bending properties is not significant when the plate thickness is thin. This influence becomes higher with an increase in the plate thickness. A 10 degrees braiding angle has been seen to be appropriate for all the cases under consideration. The present study indicates that the braided composite plate with 2.6mm thickness can be suitable for forearm treatment whereas the braided composite plate of 3.2mm thickness is applicable to femur or tibia fixation. PMID:12726720

Fujihara, K; Huang, Zheng-Ming; Ramakrishna, S; Satknanantham, K; Hamada, H

2003-07-01

259

A unique approach to accurately measure thickness in thick multilayers.  

PubMed

X-ray optics called multilayer Laue lenses (MLLs) provide a promising path to focusing hard X-rays with high focusing efficiency at a resolution between 5?nm and 20?nm. MLLs consist of thousands of depth-graded thin layers. The thickness of each layer obeys the linear zone plate law. X-ray beamline tests have been performed on magnetron sputter-deposited WSi(2)/Si MLLs at the Advanced Photon Source/Center for Nanoscale Materials 26-ID nanoprobe beamline. However, it is still very challenging to accurately grow each layer at the designed thickness during deposition; errors introduced during thickness measurements of thousands of layers lead to inaccurate MLL structures. Here, a new metrology approach that can accurately measure thickness by introducing regular marks on the cross section of thousands of layers using a focused ion beam is reported. This new measurement method is compared with a previous method. More accurate results are obtained using the new measurement approach. PMID:22514179

Shi, Bing; Hiller, Jon M; Liu, Yuzi; Liu, Chian; Qian, Jun; Gades, Lisa; Wieczorek, Michael J; Marander, Albert T; Maser, Jorg; Assoufid, Lahsen

2012-03-20

260

Discrete singular convolution method for buckling analysis of rectangular Mindlin plates  

Microsoft Academic Search

The discrete singular convolution (DSC) method is proposed for solving the elastic buckling problem of thick rectangular plates under a uniaxial compressive loading. To allow for the effect of transverse shear deformation in thick plates, the Mindlin plate theory has been adopted. The numerical results are checked against available analytical and other numerical solutions. It is found that the convergence

H. Ersoy; Ö. Civalek; M. Gürses

2009-01-01

261

Micro hot plate-based sensor array system for the detection of environmentally relevant gases.  

PubMed

A monolithic stand-alone gas sensor system is presented, which includes on a single chip an array of three metal oxide-coated micro hot plates with integrated MOS-transistor heaters, as well as a specifically designed digital system architecture. An octagonal-shaped micro hot plate design with MOS-transistor heaters has been adopted for the three gas sensors. The integrated circuitry includes a programmable digital temperature regulation, digital sensor readout units, and a standard serial interface. The programmable digital temperature controllers enable individual regulation of the micro hot plate temperatures in constant or dynamic mode. Nanocrystalline tin oxide thick films with different Pd dopings (undoped, 0.2 and 3 wt %) were used. Gas test measurements for environmentally relevant gases were carried out and evidenced detection limits of less than 1 ppm for carbon monoxide, or 100 ppm for methane, both at 40% relative humidity. Temperature modulation techniques were successfully applied for improved analyte discrimination. PMID:17007499

Graf, M; Frey, U; Taschini, S; Hierlemann, A

2006-10-01

262

Safe touch temperatures for hot plates.  

PubMed

A finite difference heat transfer model has been developed to predict the Safe Touch Temperatures (STT) for plates made of different materials. SST can be defined as the highest temperature at which no pain is felt when the surface is touched for a long enough period to allow safe handling of the equipment. The criterion used to quantify damage is the "damage function" that was originally proposed by Henriques and Moritz. There are several uncertainties present in the physiological and thermal properties of the skin that give rise to a solution range rather than a single solution. Certain simplifying assumptions are made that tend to yield solutions for STT that are toward the lower or "safe" end of the solution range. The model developed is a two-dimensional axisymmetric model in cylindrical coordinates. A finite difference scheme that uses the Alternating Direction Implicit method is used to solve the problem. It is a second-order scheme in both space and time domains. A parametric analysis of the model is performed to isolate those factors that affect the STT to the greatest extent. Data are presented for a variety of cases, which cover commonly observed ranges in material and geometric properties. It is found that the material properties, namely thermal conductivity and volumetric heat capacity, and the plate thickness ratio are the three most important parameters. These three parameters account for a range of STT from 56 degrees C-100 degrees C with thick metals at the low end and thin metals and plastics in the high range. This method represents a significant improvement over existing standard practices. PMID:10412456

Subramanian, B; Chato, J C

1998-12-01

263

Optimization of neutron imaging plate  

NASA Astrophysics Data System (ADS)

Considering the elementary processes of neutron detection occurring in the neutron imaging plate (NIP) has optimized the performance of NIP. For these processes, the color center creation efficiencies (?cc values) have been experimentally determined with NIPs which have different mole fraction of photostimulated (PSL) material (?PSL values) and different thickness (t). The effectiveness of the optimization procedure has been demonstrated by the measurement of the neutron diffraction intensities from a hen egg-white lysozyme protein crystal.

Haga, Y. K.; Neriishi, K.; Takahashi, K.; Niimura, N.

2002-07-01

264

Learning Assessment #1 - Plate Tectonics  

NSDL National Science Digital Library

In Part 1 of this activity, students are provided with a blank topographic profile and an associated tectonic plate boundary map. Students are asked to draw a schematic cross-section on the profile down to the asthenosphere including tectonic plates (with relative thicknesses of crust etc. appropriately illustrated), arrows indicating directions of plate movement, tectonic features (mid-ocean ridges, trenches and volcanic arcs) and symbols indicating where melting is occurring at depth. In Part 2, students are asked to provide geological and geophysical lines of evidence to support their placement of convergent and divergent boundaries, respectively. A bonus question asks students to predict what would happen if spreading along the Atlantic mid-ocean ridge were to stop. Students are referred to appropriate sections of the textbook to guide them in completing all the parts of this activity. Students are also provided with a checklist of required elements for both parts of the assignment.

Speta, Michelle; Reid, Leslie

265

A preliminary study of bending stiffness alteration in shape changing nitinol plates for fracture fixation.  

PubMed

Nitinol is a promising biomaterial based on its remarkable shape changing capacity, biocompatibility, and resilient mechanical properties. Until now, very limited applications have been tested for the use of Nitinol plates for fracture fixation in orthopaedics. Newly designed fracture-fixation plates are tested by four-point bending to examine a change in equivalent bending stiffness before and after shape transformation. The goal of stiffness alterable bone plates is to optimize the healing process during osteosynthesis in situ that is customized in time of onset, percent change as well as being performed non-invasively for the patient. The equivalent bending stiffness in plates of varying thicknesses changed before and after shape transformation in the range of 24-73% (p values <0.05 for all tests). Tests on a Nitinol plate of 3.0 mm increased in stiffness from 0.81 to 0.98 Nm² (corresponding standard deviation 0.08 and 0.05) and shared a good correlation to results from numerical calculation. The stiffness of the tested fracture-fixation plates can be altered in a consistent matter that would be predicted by determining the change of the cross-sectional area moment of inertia. PMID:21286815

Olender, Gavin; Pfeifer, Ronny; Müller, Christian W; Gösling, Thomas; Barcikowski, Stephan; Hurschler, Christof

2011-02-01

266

49 CFR 230.26 - Tensile strength of shell plates.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Tensile strength of shell plates. 230.26 Section 230...MAINTENANCE STANDARDS Boilers and Appurtenances Strength of Materials § 230.26 Tensile strength of shell plates. When the tensile...

2012-10-01

267

49 CFR 230.26 - Tensile strength of shell plates.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Tensile strength of shell plates. 230.26 Section 230...MAINTENANCE STANDARDS Boilers and Appurtenances Strength of Materials § 230.26 Tensile strength of shell plates. When the tensile...

2011-10-01

268

30 CFR 56.12032 - Inspection and cover plates.  

Code of Federal Regulations, 2013 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12032 Inspection and cover plates. Inspection and cover plates on electrical equipment and junction boxes...

2013-07-01

269

49 CFR 230.26 - Tensile strength of shell plates.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Tensile strength of shell plates. 230.26 Section 230...MAINTENANCE STANDARDS Boilers and Appurtenances Strength of Materials § 230.26 Tensile strength of shell plates. When the tensile...

2010-10-01

270

49 CFR 230.26 - Tensile strength of shell plates.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 2009-10-01 false Tensile strength of shell plates. 230.26 Section 230...MAINTENANCE STANDARDS Boilers and Appurtenances Strength of Materials § 230.26 Tensile strength of shell plates. When the tensile...

2009-10-01

271

Thermal Buckling of Functionally Graded Plates Resting On Elastic Foundations Using the Trigonometric Theory  

Microsoft Academic Search

In this article, thermal buckling analysis of functionally graded material (FGM) plates resting on two-parameter Pasternak's foundations is investigated. Equilibrium and stability equations of FGM plates are derived based on the trigonometric shear deformation plate theory and includes the plate foundation interaction and thermal effects. The material properties vary according to a power law form through the thickness coordinate. The

A. M. Zenkour; M. Sobhy

2011-01-01

272

Rozhen Observatory wide-field plate archives  

NASA Astrophysics Data System (ADS)

This paper provides an overview of the wide-field (>10) plate archives at disposal in the Institute of Astronomy and National Astronomical Observatory Rozhen of the Bulgarian Academy of Sciences. The plates with total number 10093 are obtained in the period November 1978 - February 1998 with the 2 m RCC telescope and 50/70/172 cm Schmidt telescope. The available plate catalogues are upgraded with new information, as well as with link to the digitized logbooks (in JPEG file format). The digitization with high quality EPSON flatbed scanners of the available 2 m RCC telescope plates (with low resolution in JPEG, and with high resolution in standardized FITS file format) is accomplished. The digitization of the available 50/70/172 cm Schmidt telescope plates is running. The low resolution images of the scanned Rozhen plates are included in the Wide-Field Plate Database (http://wfpdb.org) and accessible online.

Tsvetkova, K.; Tsvetkov, M.

2013-01-01

273

The Biggest Plates on Earth: Plate Tectonics  

NSDL National Science Digital Library

In this lesson, students investigate the movement of Earth's tectonic plates, the results of these movements, and how magnetic anomalies present at spreading centers document the motion of the crust. As a result of this activity, students will be able to describe the motion of tectonic plates, differentiate between three types of plate boundaries, infer what type of boundary exists between two tectonic plates, and understand how magnetic anomalies provide a record of geologic history and crustal motion around spreading centers. As an example, they will also describe plate boundaries and tectonic activity in the vicinity of the Juan de Fuca plate adjacent to the Pacific Northwest coast of North America.

274

MHD ekman layer on a porous plate  

Microsoft Academic Search

Summary  An exact solution of the steady three-dimensional Navier-Stokes equations is obtained for the case of flow past a porous plate\\u000a at zero incidence in a rotating frame of reference by using similarity analysis. In particular, the behaviour of the MHD Ekman\\u000a layer on a flat plate, subjected to suction and blowing, is studied. It is seen that the Ekman-layer thickness

S. Narasimha Murthy; R. K. Prabhakar Ram

1975-01-01

275

MHD Ekman layer on a porous plate  

Microsoft Academic Search

An exact solution of the steady three-dimensional Navier-Stokes equations is obtained for the case of flow past a porous plate at zero incidence in a rotating frame of reference by using similarity analysis. The behavior of the MHD Ekman layer on a flat plate, subjected to suction and blowing, is studied. It is shown that the Ekman-layer thickness is inversely

S. N. Murthy; R. K. P. Ram

1975-01-01

276

Plate flexure and mechanics: Observational constraints  

Microsoft Academic Search

Plate flexure is a phenomenon that describes how the lithosphere responds to long-term (>10^5 a) geological loads. By comparing the flexure in the vicinity of ice, volcano, and sediment loads to predictions based on simple plate models it has been possible to estimate the effective elastic thickness of the lithosphere, T_e. In the oceans, T_e is the range 2-50 km

A. B. Watts; E. B. Burov

2003-01-01

277

Intermittent Plate Tectonics  

Microsoft Academic Search

Intermittent Plate Tectonics A basic premise of Earth Science is that plate tectonics has been continuously operating since it began early in Earth's history. Yet, plate-tectonic theory itself, specifically the collisional phase of the Wilson Cycle, constitutes a process that is capable of stopping all plate motion. The plausibility of a plate-tectonic hiatus is most easily illustrated by considering the

P. G. Silver; M. D. Behn

2006-01-01

278

Petrology and plate tectonics  

Microsoft Academic Search

Petrology played an important role in the formulation of plate tectonics and early plate tectonic interpretations of the geologic past. In the last few years widespread interest in plate tectonics and progress in plate tectonic interpretations have begun to give petrology various feedback effects.In the period 1971–1974 there were two symposiums intended particularly to connect petrology with plate tectonics [Wyllie,

Akiho Miyashiro

1975-01-01

279

Measurement of Liquid Film Thickness by a Fringe Method  

Microsoft Academic Search

A technique was developed and tested to measure the local thickness of a droplet or a liquid film on a surface of an opaque or thick single transparent plate by an interference fringe pattern that was easily formed by reflecting laser lights. Monochromatic epi-illumination through an objective lens of a conventional microscope was provided by a 5 mW or 300

Akira Kariyasaki; Yoshikazu Yamasaki; Masazumi Kagawa; Tohru Nagashima; Akiharu Ousaka; Shigeharu Morooka

2009-01-01

280

Sinusoidal Response of a Thin Viscoplastic Plate with Severe Temperature Gradient.  

National Technical Information Service (NTIS)

A mathematical model for the sinusoidal vibratory response of a thin plate subjected to a through the thickness temperature gradient is developed. An 85% copper/15% niobium composite plate was modeled using a temperature and frequency dependent model of t...

K. J. Fischer

1990-01-01

281

Computing relative plate velocities: a primer  

SciTech Connect

Standard models of present-day plate motions are framed in terms of rates and poles of rotation, in accordance with the well-known theorem due to Euler. This article shows how computation of relative plate velocities from such models can be viewed as a simple problem in spherical trigonometry. A FORTRAN subroutine is provided to perform the necessary computations.

Bevis, M.

1987-08-01

282

Plate Tectonics: Consequences of Plate Interactions  

NSDL National Science Digital Library

This Science Object is the fourth of five Science Objects in the Plate Tectonic SciPack. It identifies the events that may occur and landscapes that form as a result of different plate interactions. The areas along plate margins are active. Plates pushing against one another can cause earthquakes, volcanoes, mountain formation, and very deep ocean trenches. Plates pulling apart from one another can cause smaller earthquakes, magma rising to the surface, volcanoes, and oceanic valleys and mountains from sea-floor spreading. Plates sliding past one another can cause earthquakes and rock deformation. Learning Outcomes:� Explain why volcanoes and earthquakes occur along plate boundaries. � Explain how new sea floor is created and destroyed.� Describe features that may be seen on the surface as a result of plate interactions.

National Science Teachers Association (NSTA)

2006-11-01

283

46 CFR 64.17 - Minimum tank thickness.  

Code of Federal Regulations, 2011 CFR

...thickness. 64.17 Section 64.17 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS Standards for an MPT § 64.17 Minimum tank thickness....

2011-10-01

284

Plate Tectonics: Diverging, Converging, and Transform Boundaries  

NSDL National Science Digital Library

In this lesson, students will learn to distinguish the different layers of the Earth, observe the effects of plate movements, and explore the reasons for earthquakes and volcanoes. They will label and measure the thicknesses of each layer of the Earth (lithosphere, asthenosphere, etc.) and record their results, construct models from sand and clay to illustrate what happens at the three types of plate boundaries (transform, diverging, and converging), and investigate convergent plate boundaries to see which scenarios may create earthquakes and/or volcanoes.

285

A THUMBNAIL HISTORY OF HETEROTROPHIC PLATE COUNT (HPC) METHODOLOGY IN THE UNITED STATES  

EPA Science Inventory

Over the past 100 years, the method of determining the number of bacteria in water, foods or other materials has been termed variously as: bacterial plate count, total plate count, total viable plate count, aerobic plate count, standard plate cound and more recently, heterotrophi...

286

49 CFR 179.100-6 - Thickness of plates.  

Code of Federal Regulations, 2012 CFR

...tank shell and heads must not be less than that specified in § 179.101, nor that calculated by the following formula: t = Pd / 2SE Where: d = Inside diameter in inches; E = 1.0 welded joint efficiency; except for heads with...

2012-10-01

287

49 CFR 179.100-6 - Thickness of plates.  

Code of Federal Regulations, 2011 CFR

...tank shell and heads must not be less than that specified in § 179.101, nor that calculated by the following formula: t = Pd / 2SE Where: d = Inside diameter in inches; E = 1.0 welded joint efficiency; except for heads with...

2011-10-01

288

Volcano spacing and plate rigidity  

SciTech Connect

In-plane stresses, which accompany the flexural deformation of the lithosphere under the load adjacent volcanoes, may govern the spacing of volcanoes in hotspot provinces. Specifically, compressive stresses in the vicinity of a volcano prevent new upwelling in this area, forcing a new volcano to develop at a minimum distance that is equal to the distance in which the radial stresses change from compressional to tensile (the inflection point). If a volcano is modeled as a point load on a thin elastic plate, then the distance to the inflection point is proportional to the thickness of the plate to the power of 3/4. Compilation of volcano spacing in seven volcanic groups in East Africa and seven volcanic groups of oceanic hotspots shows significant correlation with the elastic thickness of the plate and matches the calculated distance to the inflection point. In contrast, volcano spacing in island arcs and over subduction zones is fairly uniform and is much larger than predicted by the distance to the inflection point, reflecting differences in the geometry of the source and the upwelling areas.

Brink, U. (Stanford Univ., California (USA))

1991-04-01

289

MTR plates modeling with MAIA  

SciTech Connect

MAIA is a thermo-mechanical code dedicated to the modeling of MTR fuel plates. The main physical phenomena modeled in the code are the cladding oxidation, the interaction between fuel and Al-matrix, the swelling due to fission products and the Al/fuel particles interaction. The creeping of the plate can be modeled in the mechanical calculation. MAIA has been validated on U-Mo dispersion fuel experiments such as IRIS 1 and 2 and FUTURE. The results are in rather good agreement with post-irradiation examinations. MAIA can also be used to calculate in-pile behavior of U{sub 3}Si{sub 2} plates as in the SHARE experiment irradiated in the SCK/Mol BR2 reactor. The main outputs given by MAIA throughout the irradiation are temperatures, cladding oxidation thickness, interaction thickness, volume fraction of meat constituents, swelling, displacements, strains and stresses. MAIA is originally a two-dimensional code but a three-dimensional version is currently under development. (author)

Marelle, V.; Dubois, S.; Ripert, M.; Noirot, J. [DEN/DEC, CEA Cadarache, 13108 St Paul Lez Durance (France); Lemoine, P. [DEN/DSOE, CEA Saclay, 91191 Gif sur Yvette (France)

2008-07-15

290

Statistical Mechanics and Shape Transitions in Microscopic Plates  

NASA Astrophysics Data System (ADS)

We investigate the statistical mechanics of elliptical plates of parabolic thickness with free boundary condition using both analytical techniques and Monte Carlo simulation. We consider the energy landscape of this system and show that plates with spontaneous Gaussian curvature exhibit two minima while plates with zero Gaussian curvature only exhibit one stable conformation. For plate that exhibits bistability, it can undergo shape transitions between the two conformation minima if the white noise is large enough. Plates with negative spontaneous Gaussian curvature are found to be more susceptible to shape changes than its positive counterparts. Our results are applicable to many disk-like objects in the microscopic world where fluctuation effects are important.

Hou Yong, Ee; Mahadevan, L.

2013-03-01

291

Measurement of absolute optical thickness by wavelength tuning interferometer  

NASA Astrophysics Data System (ADS)

Absolute optical thickness is a fundamental parameter for the design of optical elements. In semiconductor industry, it is necessary to measure the absolute optical thickness of the central part of the projection lenses with a high accuracy. However, even when the geometrical thickness is perfectly known, a typical refractive index of fused-silica has an ambiguity of 6 × 10-5 that gives an uncertainty of 180 nm in the optical thickness for a 3 mm-thick plate. Moreover, the optical thickness measured by white light interferometry and wavelength tuning interferometry is an optical thickness with respect to not the ordinary refractive index but the group refractive index. We measured the ordinary optical thickness of a fused silica plate of 6-inch square and 3 mm thickness by a wavelength tuning interferometer with a tunable phase shifting technique. We assumed the typical refractive index and dispersion of the fused silica as approximate values. The absolute interference order for the optical thickness was finally estimated, which gives a measurement resolution of typically 10 nm for the optical thickness.

Hibino, Kenichi; Kim, Yangjin; Bitou, Youichi; Mitsuishi, Mamoru

2011-08-01

292

Determination of Deformations Due to the Forming Operations of Plates.  

National Technical Information Service (NTIS)

Formulas for predicting the deformation of thick plates subjected to various forming techniques were verified and improved. By knowing expected deformation, boiler manufacturers can better judge the utility of post-forming heat treatments. Deformation of ...

C. Bouhelier Y. Marez

1982-01-01

293

Characterization of an ultra-thick positive photoresist for electroplating applications  

NASA Astrophysics Data System (ADS)

The performance requirements for ultra-thick photoresists have increased rapidly with the dramatic growth in new lithographic applications that require electroplating processes. Two of the main applications for ultra-thick photoresists are nanotechnology (MEMS) and advanced packaging. Flipchip packaging has become widely adopted to address electrical device performance and chip form factor considerations. The growth in the nanotechnology market is driven by a wide range of products, which include accelerometers, ink jet print heads, biomedical sensors and optical switches. Electroplating levels for these applications require a photosensitive polymer material capable of coating, exposing and plating with conventional semiconductor equipment and standard ancillary process chemicals. A single coat step to achieve the final photoresist thickness is critical to minimize the number of process steps and cycle time. The sidewall profile, aspect ratio, electroplating durability and subsequent stripability are all important. This study characterized a novel positive photosensitive chemically amplified photoresist (ShinEtsu SIPR) for the use in a 65 µm thick electroplating level on copper. The lithographic performance of the ultra-thick positive photoresist was optimized using a broad band, low numerical aperture, 1x stepper to control critical dimensions (CD), sidewall angles and aspect ratios. Cross sectional SEM analysis, contrast curves, process linearity, and process latitude plots were used to establish the lithographic capabilities. High aspect ratio structures were then electroplated using the optimized photoresist process to demonstrate photoresist durability and stripability. A recommended process flow is described for this photoresist and stepper.

Flack, Warren W.; Nguyen, Ha-Ai; Capsuto, Elliott S.

2003-06-01

294

Plate Tectonics Animation  

NSDL National Science Digital Library

Plate tectonics describes the behavior of Earth's outer shell, with pieces (plates) bumping and grinding and jostling each other about. Explore these maps and animations to get a jump start on understanding plate tectonic processes, history, and how motion of the plates affects our planet today.

2002-01-01

295

CALUTRON FACE PLATE  

Microsoft Academic Search

The construction of a removable cover plate for a calutron tank is ; described. The plate is fabricated of a rectangular frame member to which is ; welded a bowed or dished plate of thin steel, reinforced with transverse ; stiffening ribs. When the tank is placed between the poles of a magnet, the ; plate may be pivoted away

Brobeck

1959-01-01

296

Stiffened plates in bending  

Microsoft Academic Search

A semianalytical method developed by the author for the analysis of bare plates has been extended to the static analysis of stiffened plates. Both concentric and eccentric stiffeners have been considered. Deposition of the stiffener eccentric to the plate gives rise to axial and bending displacements in the middle plane of the plate. Three coupled differential equations are resulted due

M. Mukhopadhyay

1994-01-01

297

Automotive composite fuel cell bipolar plates: Hydrogen permeation concerns  

Microsoft Academic Search

At present proton exchange membrane (PEM) performance levels and fuel cell stack operating conditions, require a plate area specific resistance of less than 30mohmcm2 and a plate thickness of less than 2mm are required to meet the vehicular volumetric power density target (>2kWl?1). Unfortunately, it is difficult to meet these targets, and simultaneously obtain good mechanical properties and low through-thickness

Richard Blunk; Feng Zhong; John Owens

2006-01-01

298

Microstructure of explosively loaded 304 stainless steel flyer plate  

SciTech Connect

A 304 SS flyer plate 0.54 cm thick was driven at 25 GPa at 2 ..mu..sec pulse duration. A figure illustrates the increase in hardness through the plate thickness. The higher hardness occurs at the bottom of the flyer plate. Stain-induced ..cap alpha..'-martensite morphology was obtained in the 304 specimen, just below the flyer plate from the same impact. The flyer plate microstructures from top to bottom show an increase in ..cap alpha..'-martensite as well as a significant increase in the residual dislocation densities. The ..cap alpha..'-martensite within the flyer plate for the most part is strain-induced and is observed to coalesce into laths along the <110>, in addition to being observed in a blocky structure.

Johnson, K.A. (Los Alamos National Lab., NM); Staudhammer, K.P.; Murr, L.E.

1982-01-01

299

Moiré holographic analysis of reinforced plate models  

Microsoft Academic Search

This paper deals with an extension of moiré holography for structural analysis on reinforced plate models. It is shown that unequal optical paths, caused by lack of uniform thickness, are compensated for and do not alter the moiré fringe patterns. Moreover, a simple technique is described for replicating high-sensitivity moiré gratings on Plexiglas models. The validity of the method has

D. Di Chirico; F. Ginesu; R. Rossi

1989-01-01

300

Taub, Rindler, and the static plate  

Microsoft Academic Search

An infinite 3D plate of homogeneous incompressible fluid is considered, with finite thickness, together with a 2D infinite homogeneous mass in its centre. Einstein equations are exactly solved, in the interior of the 3D mass. The solution is joined to the exterior vacuum metric of Taub. Every value for the 2D mass, positive or negative, allows a perfect junction. Also

A F F Teixeira

2005-01-01

301

Mechanics of Projectile Impact against Thin Plates.  

National Technical Information Service (NTIS)

A comprehensive theoretical and experimental investigation was undertaken to study the effects of projectile impact on plates involving targets of soft aluminum and mild steel, with thicknesses ranging from 0.05 to 1 in. The preponderance of the tests and...

W. Goldsmith

1984-01-01

302

Elastic Wave Dispersion in Laminated Composite Plate,  

National Technical Information Service (NTIS)

In this paper we use the stiffness method that was presented in to study dispersion of waves in a laminated plate. In this approach each lamina is divided into several sublayers and the displacement distribution through the thickness of each sublayer is a...

S. K. Datta A. H. Shah Y. Al-Nassar R. L. Bratton

1987-01-01

303

Transient waves in inhomogeneous isotropic elastic plates  

Microsoft Academic Search

Summary This paper deals with the problem of transient wave propagation in isotropic inhomogeneous elastic Cosserat plates of uniform thickness by the method of singular wave curves. The transport equations governing the growth-decay behaviour of all extensional and bending wave modes are explicitly integrated to provide a common general formula involving the material parameters and wave geometry. An example of

H. Cohen; R. S. D. Thomas

1984-01-01

304

Transient waves in inhomogeneous anisotropic elastic plates  

Microsoft Academic Search

Summary This paper considers the problem of transient wave propagation in elastic Cosserat plates that may be anisotropic, inhomogeneous, or of variable thickness. The methods of rays and of singular wave curves are combined to find and integrate the transport equations governing growth-decay behaviour of the extensional and bending wave modes to derive a common general formula involving the material

H. Cohen; R. S. D. Thomas

1986-01-01

305

A novel method for characterizing the impact response of functionally graded plates  

Microsoft Academic Search

Functionally graded material (FGM) plates are advanced composites with properties that vary continuously through the thickness of the plate. Metal-ceramic FGM plates have been proposed for use in thermal protection systems where a metal-rich interior surface of the plate gradually transitions to a ceramic-rich exterior surface of the plate. The ability of FGMs to resist impact loads must be demonstrated

Reid A. Larson

2008-01-01

306

46 CFR 64.53 - Information plate for MPTs.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 2009-10-01 false Information plate for MPTs. 64.53 Section 64.53 Shipping...Standards for an MPT § 64.53 Information plate for MPTs. (a) A corrosion-resistant metal plate containing the information in...

2009-10-01

307

46 CFR 64.53 - Information plate for MPTs.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Information plate for MPTs. 64.53 Section 64.53 Shipping...Standards for an MPT § 64.53 Information plate for MPTs. (a) A corrosion-resistant metal plate containing the information in...

2011-10-01

308

46 CFR 64.53 - Information plate for MPTs.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Information plate for MPTs. 64.53 Section 64.53 Shipping...Standards for an MPT § 64.53 Information plate for MPTs. (a) A corrosion-resistant metal plate containing the information in...

2010-10-01

309

46 CFR 64.53 - Information plate for MPTs.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Information plate for MPTs. 64.53 Section 64.53 Shipping...Standards for an MPT § 64.53 Information plate for MPTs. (a) A corrosion-resistant metal plate containing the information in...

2012-10-01

310

Mapping Plate Tectonic Boundaries  

NSDL National Science Digital Library

To prepare for this activity, students do background reading on Plate Tectonics from the course textbook. Students also participate in a lecture on the discovery and formulation of the unifying theory of plate tectonics, and the relationship between plate boundaries and geologic features such as volcanoes. Lastly, in lecture, students are introduced to a series of geologic hazards caused by certain plate tectonic interactions. The activity gives students practices at identifying plate boundaries and allows them to explore lesser known tectonically active regions.

Kerwin, Michael

311

A Love plate biosensor utilising a polymer layer  

Microsoft Academic Search

A Love plate device, based on an SSBW piezoelectric substrate coated with a polymer (PMMA) layer, was used to excite a surface guiding shear horizontal wave. The surface mass sensitivity of the device was calculated as a function of the thickness of the polymer layer, using a modelling theory derived for the polymer-Love plate. LB films were used to assess

Electra Gizeli; Nicholas J. Goddard; Christopher R. Lowe; Adrian C. Stevenson

1992-01-01

312

Dynamic fracture of plates due to impulsive load  

Microsoft Academic Search

In the present paper, the dynamic fractures of plates subjected to an impulsive load are investigated by experiments and numerical simulations. The center of the free edge of a square or rectangular plate with uniform thickness is impacted by a striker while the opposite edge and both side edges are free from stress. The dynamic fracture experiments are performed with

Masashi Daimaruya; Hidetoshi Kobayashi; Mikio Oda

1992-01-01

313

High-frequency vibrations of a piezomagnetic plate  

Microsoft Academic Search

This paper deals with a consistent derivation of the hierarchic system of two-dimensional approximate equations of a piezomagnetic plate at high frequency where the wavelength is of the order of magnitude or smaller than the plate thickness. To begin with, a generalized variational principle is reported for piezomagnetism, and the field variables are represented by the power series expansions in

Gulay Altay; M. Cengiz Dokmeci

2001-01-01

314

Flat-plate aerodynamics at very low Reynolds number  

Microsoft Academic Search

Gas flow over a flat-plate airfoil at very-low Reynolds number is investigated in order to understand the aerodynamic issues related to micro air vehicle design and performance. Studies have shown that such low Reynolds number flow exhibits rarefied phenomena and a flat plate having a thickness ratio of 5% has better aerodynamic performance than conventional streamlined airfoils. This paper simulates

Quanhua Sun; Iain D. Boyd

2004-01-01

315

Formulation of Mindlin-Engesser model for stiffened plate vibration  

Microsoft Academic Search

In this paper, a Mindlin-Engesser model is developed for the vibration analysis of moderately thick plates with arbitrarily oriented stiffeners. The theoretical derivation incorporates the Mindlin theory to account for the effects of transverse shear deformation and rotary inertia of plates, and the Engesser theory to account for the shear deformation of stiffeners with the inclusion of torsion effect. In

K. M. Liew; Y. Xiang; S. Kitipornchai; J. L. Meek

1995-01-01

316

Electroless copper plating on silicon surface for MEMS  

Microsoft Academic Search

Some newly developed techniques of electroless copper plating on a silicon surface for MEMS are reported in this paper. In order to make the electrolessly plated copper film adhere to the silicon surface perfectly, oxygen plasma bombardment combined with ion implantation and KOH etching are proposed to do physical treatment on silicon surface. The high-quality thin copper film with thickness

Yi Li; Zhihong Li; Yilong Hao; Guizhen Yan; WenGang Wu; Xiang Han

2004-01-01

317

An exact solution for buckling of functionally graded circular plates based on higher order shear deformation plate theory under uniform radial compression  

Microsoft Academic Search

In this research, mechanical buckling of circular plates composed of functionally graded materials (FGMs) is considered. Equilibrium and stability equations of a FGM circular plate under uniform radial compression are derived, based on the higher order shear deformation plate theory (HSDT). Assuming that the material properties vary as a power form of the thickness coordinate variable z and using the

M. M. Najafizadeh; H. R. Heydari

2008-01-01

318

Effects of a Mass Layer With Gradually Varying Thickness on a Quartz Crystal Microbalance  

Microsoft Academic Search

We study the effects of the nonuniform thickness of a thin mass layer on a quartz crystal microbalance. A theoretical analysis is performed on thickness-shear vibration of an AT-cut quartz plate with a nonuniform mass layer. Mindlin's two-dimen- sional equation for thickness-shear vibration of a quartz plate is used. Free vibration frequencies and modes are obtained. The ef- fects of

Nan Liu; Jiashi Yang; Weiqiu Chen

2011-01-01

319

Characterizing Plate Boundaries  

NSDL National Science Digital Library

To prepare for this exercise students read about the processes that operate at plate boundaries and how they are related to the distinct patterns of seismicity, volcanism, surface elevations (e.g., ridges versus trenches), and seafloor ages characteristic of different boundary types. During the week the assignment is available online, students have access to: (1) an index map that locates three boundaries they are to study; and (2) four maps from Sawyer's Discovering Plate Boundaries website that provide the data mentioned above. Student tasks are to: (1) document patterns in each type of data along the three targeted boundaries; and (2) use these observations in conjunction with their understandings of the processes that operate along different types of boundaries to decide whether each of the targeted sites is most likely to be a divergent, convergent, or shear boundary. This activity gives students practice in map reading, interpreting the likely tectonic setting of a boundary by pulling together constraints from several types of data, and collaborating with their classmates in an online environment. The activity also provides a foundation for understanding a wide range of phenomena that are discussed later in the semester in the context of plate tectonic processes. Teaching Tips Adaptations that allow this activity to be successful in an online environment Sawyer's Discovering Plate Boundaries is a jigsaw exercise in which students collaboratively develop an empirical classification of plate boundaries by first studying an individual data set (e.g., seismicity) and then working as part of a multidisciplinary team to develop a composite classification for the boundaries of a single plate using several types of data. In order for the classification to be truly empirical, students are not introduced to the "traditional" classification of plate boundaries till the end of the exercise. In adapting this assignment to the online environment I have: (1) asked students to prepare by becoming familiar with the standard classification of plate boundaries and the processes that operate at them; (2) limited their work to three targeted boundaries of different types; and (3) provided guidance about which features to look for in the each data set. I have found that these modifications help online students, who often work alone "on their own schedules", to avoid getting "lost" and frustrated with the assignment and to compensate for the lack of collaborative input they would receive in a classroom setting. Elements of this activity that are most effective The success of this exercise is really seems to depend on how well a student follows the directions. If a student learns about the geologic differences among plate boundaries, makes careful observations, and thoughtfully compares his or her observations to the expected patterns he or she typically does quite well based on answers to the follow-up questions. If, on the other hand, a student simply looks up the types of the targeted boundaries on a map and then attempts to "back out" the observations that he or she thinks should fit, the result is often inconsistency and a poor score on the questions. (I can often tell which approach a student is taking based on the queries they post to the discussion board, but rarely seem to be able to get those who are trying to work backwards through the assignment to change direction.) Recommendations for other faculty adapting this activity to their own course: To date my experience developing an engaging online exercise to help students learn the principles of plate tectonics has only been partly successful. I think that having such an exercise is critical, however, because this topic provides the framework for so much of what we learn in the geosciences. Based on my efforts to adapt elements of Discovering Plate Boundaries to an online environment I would offer three recommendations. (1) Provide examples. Confronted with an unfamiliar map students are sometimes confused when asked to decide if seafloor age, for example, is uniform or variable along the length of a boundary. Showing them what you mean using snapshots from a map can often clear questions like this up quickly. Similarly, for written work a single example that gives them a clear sense of "what you're looking for" and can often head off a lot of questions. (2) Choose the boundaries you ask students to study carefully. The scarcity of documented volcanism along a mid-ocean ridge or the burial of seafloor age belts by sediment along a trench can result in student observations that are correct, but problematic for correctly assessing the nature of a boundary. (3) Stay on top of student questions and comments, and be prepared to make well-publicized "mid-course corrections" if something you thought was clear turns out to be misunderstood. These minor corrections happen naturally in face-to-face classes but can require real diligence to catch and correct in the online environment.

Hirt, Bill

320

Comparison in image quality and noise component of columnar phosphor plate and powder phosphor plate  

NASA Astrophysics Data System (ADS)

For Computed Radiography (CR) systems that use a columnar phosphor plate (CPP) and a powder phosphor plate (PPP), we designed the systems to obtain the best image quality. To determine the optimum phosphor layer thickness for each phosphor plate, the relationship between the intensity and spatial spread of photo-stimulated luminescence (PSL), and the phosphor layer thickness of the phosphor plate is quantitatively clarified. Next, to determine the stimulation light intensity, we measured PSL, modulation transfer function (MTF) and detective quantum efficiency (DQE) by varying the stimulation light intensity, using the determined optimum phosphor layer thickness. We also investigated the noise components of each phosphor plate. Results show that, compared to the PPP, the CPP is more favorable in allowing thicker phosphor layer without reduction in MTF. As the result of the relationship between the layer thickness and the PSL, noise analysis, it was confirmed that the CPP could detect PSL in the deep region of the phosphor layer without reducing the intensity of PSL. This suggests that in comparison to the PPP, the CPP can make efficient use of X-ray information, thereby promising to enhance image quality and to reduce exposure dose.

Shimada, Katsumi; Yasuda, Hiroaki; Arakawa, Satoshi; Kuwabara, Takao; Takasu, Atsunori; Iwabuchi, Yasuo; Katou, Munetaka

2007-03-01

321

Non-cyanide silver plating  

SciTech Connect

Lawrence Livermore National Laboratory (LLNL) and Technic, Inc. have entered into a CRADA (Cooperative Research and Development Agreement) with the goal of providing industry with an environmentally benign alternative to the presently used silver cyanide plating process. This project has been in place for about six months and results are quite promising. The main objective, that of deposition of deposits as thick as 125 um (5 mils), has been met. Property data such as stress and hardness have been obtained and the structure of the deposit has been analyzed via metallography and x-ray diffraction. These results will be presented in this paper, along with plans for future work.

Dini, J.W.

1995-11-07

322

Local plate/rod descriptors of 3D trabecular bone micro-CT images from medial axis topologic analysis  

SciTech Connect

Purpose: Trabecular bone microarchitecture is made of a complex network of plate and rod structures evolving with age and disease. The purpose of this article is to propose a new 3D local analysis method for the quantitative assessment of parameters related to the geometry of trabecular bone microarchitecture. Methods: The method is based on the topologic classification of the medial axis of the 3D image into branches, rods, and plates. Thanks to the reversibility of the medial axis, the classification is next extended to the whole 3D image. Finally, the percentages of rods and plates as well as their mean thicknesses are calculated. The method was applied both to simulated test images and 3D micro-CT images of human trabecular bone. Results: The classification of simulated phantoms made of plates and rods shows that the maximum error in the quantitative percentages of plate and rods is less than 6% and smaller than with the structure model index (SMI). Micro-CT images of human femoral bone taken in osteoporosis and early or advanced osteoarthritis were analyzed. Despite the large physiological variability, the present method avoids the underestimation of rods observed with other local methods. The relative percentages of rods and plates were not significantly different between osteoarthritis and osteoporotic groups, whereas their absolute percentages were in relation to an increase of rod and plate thicknesses in advanced osteoarthritis with also higher relative and absolute number of nodes. Conclusions: The proposed method is model-independent, robust to surface irregularities, and enables geometrical characterization of not only skeletal structures but entire 3D images. Its application provided more accurate results than the standard SMI on simple simulated phantoms, but the discrepancy observed on the advanced osteoarthritis group raises questions that will require further investigations. The systematic use of such a local method in the characterization of trabecular bone samples could provide new insight in bone microarchitecture changes related to bone diseases or to those induced by drugs or therapy.

Peyrin, Francoise; Attali, Dominique; Chappard, Christine; Benhamou, Claude Laurent [CREATIS, UMR CNRS 5220, 69621 Villeurbanne (France); Inserm, U 630, 69621 Villeurbanne (France); Insa de Lyon, 69621 Villeurbanne (France); Universite Lyon I, 69621 Villeurbanne (France); Universite de Lyon, 69621 Villeurbanne (France) and ESRF (European Synchrotron Radiation Facility), BP 220, 38043 Grenoble (France); GIPSA Laboratory, UMR CNRS 5216, 38402 Grenoble (France); Inserm, U 658, 45032 Orleans Cedex 1 (France) and B20A, UMR7052 CNRS, Universite Paris 7, 75010 Paris (France); Inserm, U 658, 45032 Orleans Cedex 1 (France)

2010-08-15

323

Three-dimensional dynamic models of subducting plate-overriding plate-upper mantle interaction  

NASA Astrophysics Data System (ADS)

We present fully dynamic generic three-dimensional laboratory models of progressive subduction with an overriding plate and a weak subduction zone interface. Overriding plate thickness (TOP) is varied systematically (in the range 0-2.5 cm scaling to 0-125 km) to investigate its effect on subduction kinematics and overriding plate deformation. The general pattern of subduction is the same for all models with slab draping on the 670 km discontinuity, comparable slab dip angles, trench retreat, trenchward subducting plate motion, and a concave trench curvature. The narrow slab models only show overriding plate extension. Subduction partitioning (vSP? / (vSP? + vT?)) increases with increasing TOP, where trenchward subducting plate motion (vSP?) increases at the expense of trench retreat (vT?). This results from an increase in trench suction force with increasing TOP, which retards trench retreat. An increase in TOP also corresponds to a decrease in overriding plate extension and curvature because a thicker overriding plate provides more resistance to deform. Overriding plate extension is maximum at a scaled distance of ~200-400 km from the trench, not at the trench, suggesting that basal shear tractions resulting from mantle flow below the overriding plate primarily drive extension rather than deviatoric tensional normal stresses at the subduction zone interface. The force that drives overriding plate extension is 5%-11% of the slab negative buoyancy force. The models show a positive correlation between vT? and overriding plate extension rate, in agreement with observations. The results suggest that slab rollback and associated toroidal mantle flow drive overriding plate extension and backarc basin formation.

Meyer, C.; Schellart, W. P.

2013-02-01

324

Ultrasonic metal sheet thickness measurement without prior wave speed calibration  

NASA Astrophysics Data System (ADS)

Conventional ultrasonic mensuration of sample thickness from one side only requires the bulk wave reverberation time and a calibration speed. This speed changes with temperature, stress, and microstructure, limiting thickness measurement accuracy. Often, only one side of a sample is accessible, making in situ calibration impossible. Non-contact ultrasound can generate multiple shear horizontal guided wave modes on one side of a metal plate. Measuring propagation times of each mode at different transducer separations, allows sheet thickness to be calculated to better than 1% accuracy for sheets of at least 1.5 mm thickness, without any calibration.

Dixon, S.; Petcher, P. A.; Fan, Y.; Maisey, D.; Nickolds, P.

2013-11-01

325

Automatic cortical thickness analysis on rodent brain  

NASA Astrophysics Data System (ADS)

Localized difference in the cortex is one of the most useful morphometric traits in human and animal brain studies. There are many tools and methods already developed to automatically measure and analyze cortical thickness for the human brain. However, these tools cannot be directly applied to rodent brains due to the different scales; even adult rodent brains are 50 to 100 times smaller than humans. This paper describes an algorithm for automatically measuring the cortical thickness of mouse and rat brains. The algorithm consists of three steps: segmentation, thickness measurement, and statistical analysis among experimental groups. The segmentation step provides the neocortex separation from other brain structures and thus is a preprocessing step for the thickness measurement. In the thickness measurement step, the thickness is computed by solving a Laplacian PDE and a transport equation. The Laplacian PDE first creates streamlines as an analogy of cortical columns; the transport equation computes the length of the streamlines. The result is stored as a thickness map over the neocortex surface. For the statistical analysis, it is important to sample thickness at corresponding points. This is achieved by the particle correspondence algorithm which minimizes entropy between dynamically moving sample points called particles. Since the computational cost of the correspondence algorithm may limit the number of corresponding points, we use thin-plate spline based interpolation to increase the number of corresponding sample points. As a driving application, we measured the thickness difference to assess the effects of adolescent intermittent ethanol exposure that persist into adulthood and performed t-test between the control and exposed rat groups. We found significantly differing regions in both hemispheres.

Lee, Joohwi; Ehlers, Cindy; Crews, Fulton; Niethammer, Marc; Budin, Francois; Paniagua, Beatriz; Sulik, Kathy; Johns, Josephine; Styner, Martin; Oguz, Ipek

2011-03-01

326

Copper plating on the polyimide film by electroless plating techniques for EMI shielding.  

PubMed

In this work, the metal plated film was prepared by electroless plating techniques. The film was prepared for the fabrication of EMI shielding. Polyimide film was treated by base solution for etching and then activated by silver. The modified polyimide film was immersed into the electroless copper plating solution which has different molar ratios of nickel in the solution. The thickness and surface morphology of copper layer on the polyimide films were characterized with scanning electron microscopy (SEM). Furthermore, EMI shielding ability of the film was calculated by measuring reflectivity of EM wave on the film surface using the equation of Schelkunoff theory. PMID:19908729

Ji, Eun Sun; Cha, Hyun Gil; Kim, Chang Woo; Kang, Dong In; Kang, Young Soo

2009-12-01

327

Vibration and buckling of bimodulus laminated plates according to a higher-order plate theory  

NASA Astrophysics Data System (ADS)

This paper presents the governing equations of rectangular simply supported single-layer and two-layer cross-ply plates of bimodulus materials related to the higher order shear deformation terms. Natural frequency parameters and buckling coefficients obtained by the iteration method are compared with published results for ordinary thick plates. The Mindlin plate theory result can be obtained by simplifying the governing equation of the higher-order plate theory formulation. The effects of higher-order shear deformation terms on neutral surface locations, buckling coefficients and natural frequencies are evaluated by observing the difference between the present higher-order theory results and the Mindlin plate theory results. Also, the bending stress is shown to affect significantly the buckling coefficient Kcr and the non-dimensional frequency parameter ?.

Doong, J.-L.; Fung, C.-P.

1988-09-01

328

Importance of Corneal Thickness  

MedlinePLUS

... Determine Corneal Thickness A pachymetry test is a simple, quick, painless test to measure the thickness of your cornea. With this measurement, your doctor can better understand your IOP reading, and develop a treatment plan that is right for your condition. The procedure ...

329

Thick film hydrogen sensor  

DOEpatents

A thick film hydrogen sensor element includes an essentially inert, electrically-insulating substrate having deposited thereon a thick film metallization forming at least two resistors. The metallization is a sintered composition of Pd and a sinterable binder such as glass frit. An essentially inert, electrically insulating, hydrogen impermeable passivation layer covers at least one of the resistors.

Hoffheins, Barbara S. (Knoxville, TN); Lauf, Robert J. (Oak Ridge, TN)

1995-01-01

330

Thick film hydrogen sensor  

DOEpatents

A thick film hydrogen sensor element includes an essentially inert, electrically-insulating substrate having deposited thereon a thick film metallization forming at least two resistors. The metallization is a sintered composition of Pd and a sinterable binder such as glass frit. An essentially inert, electrically insulating, hydrogen impermeable passivation layer covers at least one of the resistors. 8 figs.

Hoffheins, B.S.; Lauf, R.J.

1995-09-19

331

Thickness effect criterion for fatigue strength evaluation of welded steel structures  

Microsoft Academic Search

From a practical point of view, some measures to reduce the thickness effect backed by a reasonable criterion are required for fabricating structures with heavy section plates. In this study, the thickness effect was investigated by systematic experiments on welded steel joints with thicknesses ranging from 10 to 80 mm. Cruciform joints and T-joints with improved weld by overall profiling

J. Yagi; Y. Tomita; S. Machida; M. Matoba; I. Soya

1993-01-01

332

Far infrared transmission of a thick TGS single crystal at 7K, and beers' law validity  

Microsoft Academic Search

Far IR transmission of a thick Triglycine Sulfate (TGS) single crystal t=8 mm thick is compared with calculations using the absorption index measured with a very thin t=13 µm thick plate. Big discrepancies suggest the occurence of surface layers.

X. Gerbaux; H. Marin Cudraz

1990-01-01

333

Residual stress, stress relief, and inhomogeneity in aluminum plate  

Microsoft Academic Search

Through-thickness residual-stress profiles in rolled 7050-T74 aluminum plate were measured before and after stress relief by stretching (-Tx51). Measurement required adapting the crack-compliance method to measure both in-plane stress components. Unexpected features in the profiles could be explained by through-thickness yield strength variations caused by crystallographic texture.

Michael B Prime; Michael R Hill

2002-01-01

334

A novel plating process for microencapsulating metal hydrides  

SciTech Connect

One approach to increasing the lifetime of the metal hydride electrode has been the use of conventional electroless plating to produce a coating of copper or nickel on the surface of the metal hydride powders. In this paper, a novel method for microencapsulating the active electrode powders is presented. This new plating technique takes advantage of the reducing power of hydrogen already stored inside the metal hydride to plate a variety of metals onto metal hydride materials. This method greatly simplifies electroless plating for these powders, eliminating the need for stabilizers and additives typically required for conventional electroless plating solutions. Metals that can be electrolessly plated with stored hydrogen have been identified based on thermodynamic considerations. Experimentally, micrometers thick coatings of copper, silver, and nickel have been plated on several metal hydrides.

Law, H.H.; Vyas, B.; Zahurak, S.M.; Kammlott, G.W. [AT and T Bell Labs., Murray Hill, NJ (United States)

1996-08-01

335

Backscattering properties of small layered plates: a model for iridosomes.  

PubMed

The backscattering properties of small layered plates are studied for various size parameter values with respect to the plate thickness, plate aspect ratio, number of layers, incident direction, and polarization states of the incident light. The results are compared with the analytical results for semi-infinite plates. The phase functions and the corresponding backscattering efficiencies of the small plates are computed with the Discrete Dipole Approximation method. The angular width of the reflection peak is found to depend on both the size parameter and the aspect ratio. The criteria for using the reflectance of semi-infinite plates to approximate the backscattering efficiencies of finite size plates are quantified with respect to the number of layers, incident angle, and polarization state. PMID:23187277

Gao, Meng; You, Yu; Yang, Ping; Kattawar, George W

2012-10-22

336

Equivalent thickness conception for corner cracks  

Microsoft Academic Search

Thickness dependence of the one-parameter-based fracture toughness has been well recognized and widely studied. However, it is still a challenge to predict the fracture of structures with curved cracks from the fracture toughness data obtained from the standard through-the-thickness cracked specimens. The complicated three-dimensional (3D) stress fields near the crack front play a vital role in the fracture strength of

Peishi Yu; Chongmin She; Wanlin Guo

2010-01-01

337

Nonlinear Vibration of the Cantilever FGM Plate Based on the Third-order Shear Deformation Plate Theory  

Microsoft Academic Search

The present investigation focuses on the research of the nonlinear vibration of a cantilevered FGMs rectangular plate subjected to the transversal excitation. Materials properties of the constituents are graded in the thickness direction according to a power law distribution and are assumed to be temperature-dependent and vary along the thickness direction. In the framework of the Reddy's Third-order shear deformation

Y. X. Hao; W. Zhang

2010-01-01

338

Growth Plate Fractures  

MedlinePLUS

... Harris classification of growth plate fractures. Type I Fractures These fractures break through the bone at the ... and completely disrupting the growth plate. Type II Fractures These fractures break through part of the bone ...

339

Segmented Clutch Plates.  

National Technical Information Service (NTIS)

The patent application relates to a segmented annular clutch plate for use in any conventional clutch plate mechanism. The segments are of equal arcuate dimension so that they are interchangeable. Each segment possesses the same annular uniformily serrate...

E. F'Geppert

1981-01-01

340

Button/Plate Yielding  

SciTech Connect

An aluminum button and plate were yielded to compare the experimental and calculated button to plate stress ratios. Using the fact that compressive stress is directly proportional to area and load, the calculated button to plate stress ratio is equal to the plate to button area ratio for a constant load. The loads that caused the button and plate to yield were estimated from a load test cell graph obtained from the materials testing facility. The button was simply compressed, but the plate was compressed with a steel cylinder of the same diameter as the aluminum button. The experimental and calculated stress ratios for the button and plate are the same within experimental error. The equation for the plate bearing area is therefore correct.

Wintercorn, S.; /Fermilab

1987-06-17

341

Plate Tectonics: Further Evidence  

NSDL National Science Digital Library

The representation depicts the spreading of the sea floor along the mid-ocean ridges. The resource generally describes the theory of plate tectonics, including the movement of plates with regard to one another.

342

External Resource: Plate Tectonics  

NSDL National Science Digital Library

This Windows to the Universe interactive webpage connects students to the study and understanding of plate tectonics, the main force that shapes our planets surface. Topics: plate tectonics, lithosphere, subduction zones, faults, ridges.

1900-01-01

343

Earth's Decelerating Tectonic Plates  

SciTech Connect

Space geodetic and oceanic magnetic anomaly constraints on tectonic plate motions are employed to determine a new global map of present-day rates of change of plate velocities. This map shows that Earth's largest plate, the Pacific, is presently decelerating along with several other plates in the Pacific and Indo-Atlantic hemispheres. These plate decelerations contribute to an overall, globally averaged slowdown in tectonic plate speeds. The map of plate decelerations provides new and unique constraints on the dynamics of time-dependent convection in Earth's mantle. We employ a recently developed convection model constrained by seismic, geodynamic and mineral physics data to show that time-dependent changes in mantle buoyancy forces can explain the deceleration of the major plates in the Pacific and Indo-Atlantic hemispheres.

Forte, A M; Moucha, R; Rowley, D B; Quere, S; Mitrovica, J X; Simmons, N A; Grand, S P

2008-08-22

344

Thermal buckling of thick antisymmetric angle-ply laminates  

SciTech Connect

The buckling behavior of moderately thick antisymmetric angle-ply laminates that are simply supported and subject to a uniform temperature rise is analyzed. Transverse shear deformation is accounted for by employing the thermoelastic version of the Reissner-Mindlin theory. Results for the classical thin-plate theory are obtained as a special case. Numerical results are presented for fiber-reinforced laminates and show the effects of ply orientation, number of layers, plate thickness, and aspect ratio on the critical buckling temperature. Finally, an optimization procedure is proposed for the design of laminates having maximum resistance to thermal buckling. 17 references.

Tauchert, T.R.

1987-01-01

345

Accelerated plate tectonics.  

PubMed

The concept of a stressed elastic lithospheric plate riding on a viscous asthenosphere is used to calculate the recurrence interval of great earthquakes at convergent plate boundaries, the separation of decoupling and lithospheric earthquakes, and the migration pattern of large earthquakes along an arc. It is proposed that plate motions accelerate after great decoupling earthquakes and that most of the observed plate motions occur during short periods of time, separated by periods of relative quiescence. PMID:17799689

Anderson, D L

1975-03-21

346

Incorporation of nano zinc oxide for improvement of electroless nickel plating  

Microsoft Academic Search

The advantages of electroless nickel plating (EN) include excellent corrosion resistance, wear resistance, solderability, low porosity and uniform thickness even on complex parts and ability to plate on nonconductors. In the present study nano ZnO particles were synthesized by using an electrochemical technique and incorporated the particles into Ni–P plates. An alkaline bath was selected and used for nano zinc

S. M. A. Shibli; B. Jabeera; R. I. Anupama

2006-01-01

347

A Baffle Plate For Subsurface Acoustic Module In High Ship-noise Operation  

Microsoft Academic Search

Development of a baffle plate useful for: shielding a subsurface acoustic module from high acoustic noise of a surface ship is described. The baffle plate was made of 12.7 cm (5”) thick steel plate, octagonal in shape with a 1 m diagonal length. The lower surface was covered with a layer of an acoustic absorption material, SAPER-DTM. A test was

Ham Matsumoto; Edward Noda; J. Sharkey; Frank McHale

1991-01-01

348

Development and application of automation control system to plate production line  

Microsoft Academic Search

The automation control system to plate production line is developed independently. The whole system is divided into several levels and control functions are put into effect by the basic automation system, process automation system and human-machine-interface (HMI) system. Plate production thickness accuracy depends on the Automatic Gauge Control (AGC) function in the basic automation system for the plate mill area.

Zhi-jie Jiao; Chun-yu he; Jun Wang; Zhong Zhao

2010-01-01

349

Buckling behavior of standing laminated Mindlin plates subjected to body force and vertical loading  

Microsoft Academic Search

In this article, an exact analytical solution for stability analysis of vertical moderately thick laminated rectangular plates subjected to selfweight and top load on the basis of the first-order shear deformation plate theory is presented. It is assumed that the symmetric laminated rectangular plate is composed of transversely isotropic layers. Employing an analytical approach, the coupled governing stability equations of

M. Bodaghi; A. R. Saidi

2011-01-01

350

Vibration analysis of delaminated composite beams and plates using a higher-order finite element  

Microsoft Academic Search

In order to analyze the vibration response of delaminated composite plates of moderate thickness, a FEM model based on a simple higher-order plate theory, which can satisfy the zero transverse shear strain condition on the top and bottom surfaces of plates, has been proposed in this paper. To set up a C0-type FEM model, two artificial variables have been introduced

N. Hu; H. Fukunaga; M. Kameyama; Y. Aramaki; F. K. Chang

2002-01-01

351

Plate Tectonics: Moving Middle School Science  

NSDL National Science Digital Library

This resource guide from the Middle School Portal 2 project, written specifically for teachers, provides links to exemplary resources including background information, lessons, career information, and related national science education standards. This wiki page is about plate tectonics and features online resources that were hand-picked for middle school teachers. The resources are organized into three sets: background information (for teachers and students), activities (single-day and multiple-day), and animations. National Science Education Standards related to plate tectonics are also provided. Each resource set begins with a discussion of its strengths. For example, students work with models and data in the activities, many of which are discovery-oriented. Teaching tips and usage suggestions are offered in the set introductions and in the descriptions of individual resources. Together, the resources address topics such as the development of the plate tectonics theory and the types of plate boundaries and their locations.

Barber, Carolee; Ridgway, Judith

2004-11-01

352

Optimal truss plates  

Microsoft Academic Search

Sandwich plates comprised of truss cores faced with either planar trusses or solid sheets are optimally designed for minimum weight subject to prescribed combinations of bending and transverse shear loads. Motivated by recent advances in manufacturing possibilities, attention is focussed on plates with truss elements and faces made from a single material. The optimized plates are compared with similarly optimized

Nathan Wicks; John W Hutchinson

2001-01-01

353

Earthquakes and Plate Tectonics  

NSDL National Science Digital Library

This article describes the theory of plate tectonics and its relation to earthquakes and seismic zones. Materials include an overview of plate tectonics, a description of Earth's crustal plates and their motions, and descriptions of the four types of seismic zones.

354

Plate Tectonic Theory  

NSDL National Science Digital Library

This is the web site for a Plate Tectonics Theory class at The University of Nevada, Reno. The home page/syllabus contains links to several of the topics covered in the course. The topics with web based lecture materials are earthquake seismology, structure of the Earth, composition of the Earth, lithospheric deformation, the plate tectonics paradigm, and the driving mechanisms of plate tectonics.

Louie, John

355

Plate Tectonic Primer  

NSDL National Science Digital Library

This site gives an in-depth look at the theory of plate tectonics and how it works. The structure of the Earth is discussed, with brief rock type descriptions. The structure of the lithosphere, plate boundaries, interplate relationships, and types of plates are all covered in detail.

Fichter, Lynn

356

Lamb waves in binary locally resonant phononic plates with two-dimensional lattices  

NASA Astrophysics Data System (ADS)

The authors study the propagation of Lamb waves in two-dimensional locally resonant phononic-crystal plates, composed of periodic soft rubber fillers in epoxy host with a finite thickness. Our calculations are based on the efficient plane wave expansion formulation which utilized Mindlin's plate theory. Calculated results show that the low-frequency gaps of Lamb waves are opened up by the localized resonance mechanism. The resonant frequencies of flexure-dominated plate modes are significantly dependent not only on the radius of circular rubber fillers but also on the plate thickness. The properties of localized resonance are qualitatively analogous to the vibration of a circular thin plate.

Hsu, Jin-Chen; Wu, Tsung-Tsong

2007-05-01

357

Solderability and environmental testing of Sn-plated surfaces  

SciTech Connect

The effect of atmospheric corrosion on the solderability of Sn plated surfaces was evaluated with 60Sn-40Pb solder. Tin thicknesses of 10, 50, and 150 {mu}in on Ni plated Cu were studied. The 10 {mu}in. plating gave the smallest solder meniscus rise. A general decrease in contact angle, or increase in wettability, was observed with increasing Sn plating. The environmental exposures retarded the wetting rate and increased the time to maximum wetting, particularly with only 10 {mu}in. of Sn. Although the solderability of the 50 and 150 {mu}in. surfaces wee not significantly affected by the test conditions, an intermediate plating thickness of 100 {mu}in. is preferred for processing flexibility. 13 refs., 7 figs., 1 tab.

Sorensen, N.R.; Hosking, F.M.

1990-01-01

358

Thickness-dependent bending modulus of hexagonal boron nitride nanosheets.  

PubMed

Bending modulus of exfoliation-made single-crystalline hexagonal boron nitride nanosheets (BNNSs) with thicknesses of 25-300 nm and sizes of 1.2-3.0 microm were measured using three-point bending tests in an atomic force microscope. BNNSs suspended on an SiO(2) trench were clamped by a metal film via microfabrication based on electron beam lithography. Calculated by the plate theory of a doubly clamped plate under a concentrated load, the bending modulus of BNNSs was found to increase with the decrease of sheet thickness and approach the theoretical C(33) value of a hexagonal BN single crystal in thinner sheets (thickness<50 nm). The thickness-dependent bending modulus was suggested to be due to the layer distribution of stacking faults which were also thought to be responsible for the layer-by-layer BNNS exfoliation. PMID:19713592

Li, Chun; Bando, Yoshio; Zhi, Chunyi; Huang, Yang; Golberg, Dmitri

2009-08-28

359

A novel laser ultrasonic sensor for testing thickness  

NASA Astrophysics Data System (ADS)

A new laser ultrasonic sensor for testing samples' thickness is developed. This sensor has high-frequency response and high sensitivity. Furthermore it is easy to adjust. When the sensor is used to focus on polished iron plate, well-defined longitude-wave and its echo waves can be obtained. Based on the experimental results, the sample"s thickness can be deduced. The theoretical and experimental results are in good agreement with relative error of 0.5%.

Xu, Rongqing; Zhao, Rui; Chen, Xiao; Shen, Zhonghua; Lu, Jian; Ni, Xiaowu

2005-02-01

360

Marangoni flow on an inkjet nozzle plate  

NASA Astrophysics Data System (ADS)

In piezo inkjet printing, nozzle failures are often caused by an ink layer on the nozzle plate. It is experimentally shown that the ink layer at the nozzle is formed through streamers of ink, emanating from a central ink band on the nozzle plate. The streamers propagate over a wetting nanofilm of 13 nm thickness, directed toward the actuated nozzles. The motion of the front end of the streamers follows a power law in time with an exponent 12. The observations are consistent with a surface tension gradient driven flow. The origin of the Marangoni flow is an effective lower surfactant concentration of the ink around the nozzle.

de Jong, Jos; Reinten, Hans; Wijshoff, Herman; van den Berg, Marc; Delescen, Koos; van Dongen, Rini; Mugele, Frieder; Versluis, Michel; Lohse, Detlef

2007-11-01

361

Discovering Plate Boundaries  

NSDL National Science Digital Library

Students are initially assigned to one of four maps of the world: Seismology, Volcanology, Geochronology or Topography. They are also given a map of the world's plate boundaries and are asked to classify the boundaries based upon the data from their assigned map. Students are then assigned to a tectonic plate, such that each plate group contains at least one "expert" on each map. As a group, they must classify their plate's boundaries using data from all four maps. Recent volcanic and seismic events are discussed in the plate tectonic context. Has minimal/no quantitative component Uses geophysics to solve problems in other fields

Henning, Alison

362

40 CFR 426.44 - Pretreatment standards for existing sources.  

Code of Federal Regulations, 2013 CFR

...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) GLASS MANUFACTURING POINT SOURCE CATEGORY Plate Glass Manufacturing Subcategory § 426.44 Pretreatment standards for existing...

2013-07-01

363

40 CFR 426.46 - Pretreatment standards for new sources.  

Code of Federal Regulations, 2013 CFR

...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) GLASS MANUFACTURING POINT SOURCE CATEGORY Plate Glass Manufacturing Subcategory § 426.46 Pretreatment standards for new sources. Any...

2013-07-01

364

Geologically current plate motions  

NASA Astrophysics Data System (ADS)

We describe best-fitting angular velocities and MORVEL, a new closure-enforced set of angular velocities for the geologically current motions of 25 tectonic plates that collectively occupy 97 per cent of Earth's surface. Seafloor spreading rates and fault azimuths are used to determine the motions of 19 plates bordered by mid-ocean ridges, including all the major plates. Six smaller plates with little or no connection to the mid-ocean ridges are linked to MORVEL with GPS station velocities and azimuthal data. By design, almost no kinematic information is exchanged between the geologically determined and geodetically constrained subsets of the global circuit-MORVEL thus averages motion over geological intervals for all the major plates. Plate geometry changes relative to NUVEL-1A include the incorporation of Nubia, Lwandle and Somalia plates for the former Africa plate, Capricorn, Australia and Macquarie plates for the former Australia plate, and Sur and South America plates for the former South America plate. MORVEL also includes Amur, Philippine Sea, Sundaland and Yangtze plates, making it more useful than NUVEL-1A for studies of deformation in Asia and the western Pacific. Seafloor spreading rates are estimated over the past 0.78 Myr for intermediate and fast spreading centres and since 3.16 Ma for slow and ultraslow spreading centres. Rates are adjusted downward by 0.6-2.6mmyr-1 to compensate for the several kilometre width of magnetic reversal zones. Nearly all the NUVEL-1A angular velocities differ significantly from the MORVEL angular velocities. The many new data, revised plate geometries, and correction for outward displacement thus significantly modify our knowledge of geologically current plate motions. MORVEL indicates significantly slower 0.78-Myr-average motion across the Nazca-Antarctic and Nazca-Pacific boundaries than does NUVEL-1A, consistent with a progressive slowdown in the eastward component of Nazca plate motion since 3.16 Ma. It also indicates that motions across the Caribbean-North America and Caribbean-South America plate boundaries are twice as fast as given by NUVEL-1A. Summed, least-squares differences between angular velocities estimated from GPS and those for MORVEL, NUVEL-1 and NUVEL-1A are, respectively, 260 per cent larger for NUVEL-1 and 50 per cent larger for NUVEL-1A than for MORVEL, suggesting that MORVEL more accurately describes historically current plate motions. Significant differences between geological and GPS estimates of Nazca plate motion and Arabia-Eurasia and India-Eurasia motion are reduced but not eliminated when using MORVEL instead of NUVEL-1A, possibly indicating that changes have occurred in those plate motions since 3.16 Ma. The MORVEL and GPS estimates of Pacific-North America plate motion in western North America differ by only 2.6 +/- 1.7mmyr-1, ~25 per cent smaller than for NUVEL-1A. The remaining difference for this plate pair, assuming there are no unrecognized systematic errors and no measurable change in Pacific-North America motion over the past 1-3 Myr, indicates deformation of one or more plates in the global circuit. Tests for closure of six three-plate circuits indicate that two, Pacific-Cocos-Nazca and Sur-Nubia-Antarctic, fail closure, with respective linear velocities of non-closure of 14 +/- 5 and 3 +/- 1mmyr-1 (95 per cent confidence limits) at their triple junctions. We conclude that the rigid plate approximation continues to be tremendously useful, but-absent any unrecognized systematic errors-the plates deform measurably, possibly by thermal contraction and wide plate boundaries with deformation rates near or beneath the level of noise in plate kinematic data.

DeMets, Charles; Gordon, Richard G.; Argus, Donald F.

2010-04-01

365

Multicolor printing plate joining  

NASA Astrophysics Data System (ADS)

An upper plate having ink flow channels and a lower plate having a multicolored pattern are joined. The joining is accomplished without clogging any ink flow paths. A pattern having different colored parts and apertures is formed in a lower plate. Ink flow channels each having respective ink input ports are formed in an upper plate. The ink flow channels are coated with solder mask and the bottom of the upper plate is then coated with solder. The upper and lower plates are pressed together at from 2 to 5 psi and heated to a temperature of from 295 F to 750 F or enough to melt the solder. After the plates have cooled and the pressure is released, the solder mask is removed from the interior passageways by means of a liquid solvent.

Waters, W. J.

1984-03-01

366

Mantle Convection Moving Plates  

NSDL National Science Digital Library

This demonstration models the manner in which the convection currents in the mantle of the Earth cause movement of the plates. Convection currents in the mantle were thought, for many years, to be solely responsible for plate tectonic movements, with the movement taking rocks down at destructive margins and new rocks forming when plates spread. It is now thought likely that there are three possible driving mechanisms for plate tectonics. In addition to movement of mantle convection currents as shown in this demonstration, scientists also consider the mass of the subducted plate (the sinking slab) at the subduction zone dragging the surface part of the plate across the surface and the new plate material sliding off the higher oceanic ridges at constructive margins.

367

Tomography and thermal state of the Cocos plate subduction beneath Mexico City  

NASA Astrophysics Data System (ADS)

The geometry and thermal state of the subducting Cocos plate beneath Mexico City has been enigmatic because of the absence of a deep Wadati-Benioff zone. We present a tomographic image of the slab based on inversion of 8869 teleseismic P wave travel times measured on a portable broadband seismic network. The images combined with receiver function analysis show that the slab runs flat from the coast to near Mexico City, where it dives into the mantle just before the Trans-Mexican Volcanic Belt with a dip of ˜75°. It continues down to a depth of ˜500 km at a distance of 400 km from the trench, where the tomography reveals that the dipping portion ends. As well as standard block tomography, we invert the travel time residuals for the parameters of a thermal slab model and find a slab thickness of 40 km that is consistent with the (15 Ma) age of the Cocos plate. The combination of a young hot plate and truncation at depth can explain the lack of deep seismicity due to high temperatures and lower negative buoyancy compared with an older, thicker, nontruncated plate.

Husker, Allen; Davis, Paul M.

2009-04-01

368

A two variable refined plate theory for the bending analysis of functionally graded plates  

NASA Astrophysics Data System (ADS)

Bending analysis of functionally graded plates using the two variable refined plate theory is presented in this paper. The number of unknown functions involved is reduced to merely four, as against five in other shear deformation theories. The variationally consistent theory presented here has, in many respects, strong similarity to the classical plate theory. It does not require shear correction factors, and gives rise to such transverse shear stress variation that the transverse shear stresses vary parabolically across the thickness and satisfy shear stress free surface conditions. Material properties of the plate are assumed to be graded in the thickness direction with their distributions following a simple power-law in terms of the volume fractions of the constituents. Governing equations are derived from the principle of virtual displacements, and a closed-form solution is found for a simply supported rectangular plate subjected to sinusoidal loading by using the Navier method. Numerical results obtained by the present theory are compared with available solutions, from which it can be concluded that the proposed theory is accurate and simple in analyzing the static bending behavior of functionally graded plates.

Mechab, Ismail; Atmane, Hassen Ait; Tounsi, Abdlouahed; Belhadj, Hichem Abdesselem; Bedia, El Abbas Adda

2010-12-01

369

Materials science in pre-plated leadframes for electronic packages  

NASA Astrophysics Data System (ADS)

Au/Pd/Ni pre-plated leadframes (PPF) are high performance frames for accommodating high-end electronic packages. Cost and reliability are major concerns in their wide application. The present work, from a materials science point view, deepens the understanding of PPFs, optimizes the conventional PPFs, develops a novel PPF architecture and models the residual stress relaxation in heteroepitaxial thin films. The wire pull test, the solderability test, and High-Resolution Transmission Electron Microscopy (HRTEM) were employed to characterize the PPFs in order to understand the relationship between performance and microstructure. We optimized the electroplating profiles and determined the minimum thickness of the Pd layer with the PPF performance satisfying the industry standards. Further increasing the Pd layer thickness beyond the critical thickness will not enhance the performance more, but increase the product cost. With the optimized electroplating profile, the electroplated Au layer is epitaxially deposited on the Pd layer, and so does the Pd layer on the Ni layer. Misfit dislocations and nanotwins are present at the interface between the Pd and Ni layers, which are generated to release the about 10.4% misfit strain between the Pd and Ni lattices. This work demonstrates that the electro-deposition technique can electroplate epitaxy-like Pd films on the highly (200) textured Ni films, which are grown on the Cu substrates. A novel technique for impeding Cu out-diffusion in Cu alloy based pre-plated leadframes was developed by electroplating a 3-4 nm thick Sn layer on a Cu alloy base prior to electroplating a Ni layer. A 10-14 nm thick epitaxy-like and dense (Cu,Ni)3Sn intermetallic compound (IMC) layer is automatically formed en route of diffuse reaction, which leads to a drastic reduction in Cu out-diffusion and hence improves significantly the protection of the leadframes against oxidation and corrosion attack. The oxidation behaviours were quantified by Electron Diffraction X-ray (EX) incorporated in Scanning Electron Microscopy (SEM) in the present work, which is a good complementary to the traditional weight gain test by a balance. A diffusion/oxidation model was developed to estimate the effective diffusion coefficient of Cu in the formed IMC nanolayers. The estimated Cu diffusion coefficient in the IMC interlayer is about 1.6x10 -22m2/s at 250°C, which is around 7~11 orders lower than the interdiffusion coefficients for eta- Cu6Sn5 and epsilon- Cu3Sn phases at corresponding temperatures. Based on the dislocation theory of twinning, analytical solutions by using the hybrid superposition and Fourier transformation approach were derived for the calculation of various energies involved in the misfit twinning process. For a given epilayer thickness and lattice mismatch strain, the twin formation energy should reach its minimum to determine the twin width and a zero minimum formation energy determines the critical thickness for misfit twinning. The effect of elastic mismatch between the epilayer and the substrate on the critical thickness was studied comprehensively, revealing that an elastically soft epilayer has a large critical thickness. Moreover, a misfit-twin-and-perfect-dislocation predominance chart is constructed to predict the predominant regions of misfit twinning and perfect dislocation in the mismatch strain and the specific twin boundary energy domain. Multiple misfit twins in epilayer/substrate systems were studied by summing up the stress and displacement fields of individual twins. In principle, the energy minimization approach can be applied to multiple misfit twins, although only periodic arrays of parallel and alternating twins were investigated here in detail. The equilibrium twin width and equilibrium twin spacing of a periodic array of twins represent the misfit twin morphology. The theoretical results indicate that the difference in elastic constants between an epilayer and its substrate has great effects on the morphology of equilibrium twins. The theoretical predictions agree with experimental

Liu, Lilin

370

Choroidal thickness changes during the menstrual cycle.  

PubMed

Abstract Purpose: To evaluate the effects of the menstrual cycle on the choroidal thickness of healthy women of reproductive age using spectral-domain optical coherence tomography. Materials and methods: A total of 23 right eyes of 23 women with regular natural menstrual cycles of 28-30?d and ages 22-30 years were included in this prospective study. The choroidal thicknesses of the women were measured using high-resolution spectral-domain optical coherence tomography line scans with the activated enhanced depth imaging mode in the early follicular, ovulatory and mid-luteal phases of the menstrual cycle (3rd, 14th and 21st days) using a follow-up scanning protocol of the Spectralis optical coherence tomograph by setting the early follicular phase scan as the reference image. Choroidal thickness measurements were taken at the fovea and at two points that were 1500?µm nasal and temporal to the fovea. The mean arterial pressure, spherical equivalent, intraocular pressure, central corneal thickness and retinal and retinal nerve fiber layer thicknesses were also measured. All measurements were taken within the same menstrual cycle. Results: The mean?±?standard deviation (standard error of the mean) of subfoveal choroidal thicknesses in the early follicular, ovulatory and mid-luteal phases were 383.87?±?84.38 (17.59), 373.74?±?82.40 (17.18) and 359.09?±?79.65 (16.61) µm, respectively. The relative reductions in choroidal thickness between early follicular and ovulatory phases and early follicular and mid-luteal phases were 2.64% and 6.47%, respectively. The subfoveal choroidal thickness was decreased significantly in the mid-luteal phase when compared with both the early follicular (p?thickness in the early follicular phase were non-conclusively greater (p?=?0.071) than in the ovulatory phase. Additionally, the mean arterial pressure, spherical equivalent, intraocular pressure, central corneal thickness and retinal and retinal nerve fiber layer thicknesses did not significantly differ during the menstrual cycle (p?>?0.05 for all). Conclusions: The choroidal thickness decreased significantly in the mid-luteal phase of the menstrual cycle in young, healthy women. These findings emphasize the importance of the menstrual phase in the interpretation of choroidal thickness measurements in women of reproductive age. PMID:23841496

Ula?, Fatih; Do?an, Umit; Duran, Bülent; Kele?, Asena; A?ca, Sümeyra; Celebi, Serdal

2013-07-10

371

Thermal diffusivity of nonflat plates using the flash method  

SciTech Connect

The flash method is the standard technique to measure the thermal diffusivity of solid samples. It consists of heating the front surface of an opaque sample by a brief light pulse and detecting the temperature evolution at its rear surface. The thermal diffusivity is obtained by measuring the time corresponding to the half maximum of the temperature rise, which only depends on the sample thickness and thermal diffusivity through a simple formula. Up to now, the flash method has been restricted to flat samples. In this work, we extend the flash method to measure the thermal diffusivity of nonflat samples. In particular, we focus on plates with cylindrical and spherical shapes. The theoretical model indicates that the same expression for flat samples can also be applied to cylindrical and spherical plates, except for extremely curved samples. Accordingly, a curvature limit for the application of the expression for flat samples is established. Flash measurements on lead foils of cylindrical shape confirm the validity of the model.

Salazar, Agustin; Fuente, Raquel; Apinaniz, Estibaliz; Mendioroz, Arantza [Departamento de Fisica Aplicada I, Escuela Tecnica Superior de Ingenieria, Universidad del Pais Vasco, Alameda Urquijo s/n, 48013 Bilbao (Spain)

2011-01-15

372

Thermal diffusivity of nonflat plates using the flash method.  

PubMed

The flash method is the standard technique to measure the thermal diffusivity of solid samples. It consists of heating the front surface of an opaque sample by a brief light pulse and detecting the temperature evolution at its rear surface. The thermal diffusivity is obtained by measuring the time corresponding to the half maximum of the temperature rise, which only depends on the sample thickness and thermal diffusivity through a simple formula. Up to now, the flash method has been restricted to flat samples. In this work, we extend the flash method to measure the thermal diffusivity of nonflat samples. In particular, we focus on plates with cylindrical and spherical shapes. The theoretical model indicates that the same expression for flat samples can also be applied to cylindrical and spherical plates, except for extremely curved samples. Accordingly, a curvature limit for the application of the expression for flat samples is established. Flash measurements on lead foils of cylindrical shape confirm the validity of the model. PMID:21280851

Salazar, Agustín; Fuente, Raquel; Apiñaniz, Estibaliz; Mendioroz, Arantza

2011-01-01

373

Critical heat flux on a flat plate in a pool of subcooled liquid helium  

Microsoft Academic Search

Critical heat flux (CHF) on a flat plate in a pool of liquid helium was measured for bulk liquid temperatures ranging from saturation temperature down to 1.8 K under pressures of 101.3 and 130 kPa. Four test plates 10 mm wide×40 mm long×0.1 mm thick, made of Manganin were used. Test plates were pasted on a Fiber-Reinforced-Plastic (FRP) plate 4

K. Hata; H. Nakagawa; H. Tatsumoto; Y. Shirai; M. Shiotsu

2002-01-01

374

Nonlinear dynamic response of a functionally graded plate with a through-width surface crack  

Microsoft Academic Search

A nonlinear vibration analysis of a simply supported functionally graded rectangular plate with a through-width surface crack\\u000a is presented in this paper. The plate is subjected to a transverse excitation force. Material properties are graded in the\\u000a thickness direction according to exponential distributions. The cracked plate is treated as an assembly of two sub-plates\\u000a connected by a rotational spring at

J. Yang; Y. X. Hao; W. Zhang; S. Kitipornchai

2010-01-01

375

MEASUREMENT METHOD FOR WELDING RESIDUAL STRESS IN STEEL I-SHAPED GIRDER WITH THICK FLANGE AND ITS INFLUENCE ON LOAD CARRYING CAPACITY FOR BENDING  

NASA Astrophysics Data System (ADS)

Recently, the construction number of steel girder bridge using thick plates has been increasing. It is afraid that residual stress in the thick plates affects the load carrying capacity of the girder. Therefore, this study aims to measure the distribution of residual stresses in the thick plates by mechanical cutting method. Herein, simplified measurement method is proposed for the measurement in the thickness direction. As a result, it was found that the slope of stress distribution in the thickness direction becomes large as the thickness of the plate increases. Then, after considering the equilibriums of residual stress three-dimensionally, the residual stress was introduced into a finite element analysis model, which is the modeling of an existing bridge at the intermediate support. It was confirmed that residual stress in the thick plate does not affect the load carrying capacity of steel girder in bending.

Miyashita, Takeshi; Inaba, Naofumi; Hirayama, Shigeyuki; Liu, Cuiping; Nagai, Masatsugu

376

Growth of large KDP crystals in the form of plates  

SciTech Connect

This paper suggests a new technique of growth-oriented KDP crystals in the form of plates. The technique includes: using small oriented seeds spaced between two parallel platforms with a rapid growth of crystals between these two platforms, in a tank containing a KDP solution. As a result, crystals in the form of plates can be obtained. The thickness of the crystal plate depends on the distance between platforms. The horizontal dimensions of the plate depend on the volume of solution and the diameter of the platforms. The orientation of the plates are defined by the orientation of the seed. KDP crystals in the form of plates of two orientations are grown. The peculiarities of morphology and some characteristics of crystals are discussed.

Beriot, E; Tatartchenko, V

1998-05-01

377

Plate Wave Resonance with Air-Coupled Ultrasonics  

NASA Astrophysics Data System (ADS)

Air-coupled ultrasonic transducers can excite plate waves in metals and composites. The coincidence effect, i.e., the wave vector of plate wave coincides with projection of exciting airborne sound vector, leads to a resonance which strongly amplifies the sound transmission through the plate. The resonance depends on the angle of incidence and the frequency. In the present study, the incidence angle for maximum transmission (?max) is measured in plates of steel, aluminum, carbon fiber reinforced composites and honeycomb sandwich panels. The variations of (?max) with plate thickness are compared with theoretical values in steel, aluminum and quasi-isotropic carbon fiber composites. The enhanced transmission of air-coupled ultrasound at oblique incidence can substantially improve the probability of flaw detection in plates and especially in honeycomb structures. Experimental air-coupled ultrasonic scan of subtle flaws in CFRP laminates showed definite improvement of signal-to-noise ratio with oblique incidence at ?max.

Bar, H. N.; Dayal, V.; Barnard, D.; Hsu, D. K.

2010-02-01

378

A reassessment of the elastic thickness at the Azores Plateau  

NASA Astrophysics Data System (ADS)

The isostatic compensation of the Azores swell is investigated by a three-dimensional admittance computation between the bathymetry and both the geoid and the free air gravity anomalies. The comparison of the observed admittance with theoretical admittance models exclude the hypothesis of a hotspot origin for the swell, and point to an elastic plate model of compensation, with an average effective elastic thickness of 6 km. To investigate the possibility of shallow loading from below along the Terceira axis we also perform a local admittance computation between the bathymetry and the mantle Bouguer gravity anomaly (MBA). We find that although some loading from below is possible, the model that best fits the observed admittance is that of an elastic plate with variable thickness (varying between 2 and 6 km), loaded on top. The hypothesis of a variable elastic thickness or broken plate across the Terceira axis is explored through finite element modeling. Two-dimensional models of flexural deformation across the Terceira axis are used to re-examine the admittance function, and provide further constraints on the elastic plate thickness.

Neves, M.; Luis, J.

2003-04-01

379

Evaluation of Electron Beam Welds in Thick Materials.  

National Technical Information Service (NTIS)

This report discusses the results of a program to compare mechanical properties and economics of electron beam welds in thick sections with arc welding processes. Single pass but welds were made in 1.0-in. plates of Ti-6Al-4V, Rene' 41, 18NiCoMo maraging ...

J. M. Gerken M. T. Groves

1966-01-01

380

WFPDB: European Plate Archives  

NASA Astrophysics Data System (ADS)

The Wide-Field Plate Database (WFPDB) gives an inventory of all wide-field (>~ 1 sq. deg) photographic observations archived in astronomical institutions over the world. So it facilitates and stimulates their use and preservation as a valuable source of information for future investigations in astronomy. At present WFPDB manages plate-index information for 25% of all existing plates providing on-line access from Sofia (http://www.skyarchive.org/search) and in CDS, Strasbourg. Here we present the new development of WFPDB as an instrument for searching of long term brightness variations of different sky objects stressing on the European photographic plate collections (from existing 2 million wide-field plates more than 55% are in Europe: Germany, Russia, Ukraine, Italy, Czech Republic, etc.). We comment examples of digitization (with flatbed scanners) of the European plate archives in Sonneberg, Pulkovo, Asiago, Byurakan, Bamberg, etc. and virtual links of WFPDB with European AVO, ADS, IBVS.

Tsvetkov, Milcho

2007-08-01

381

Process-Induced Stress and Deformation in Thick-Section Thermoset Composite Laminates.  

National Technical Information Service (NTIS)

A study of process-induced stress and deformation in thick-section thermosetting composite laminates is presented. A one-dimensional cure simulation analysis is coupled to an incremental laminated plate theory model to study the relationships between comp...

J. W. Gillespie T. A. Bogetti

1990-01-01

382

Taub, Rindler, and the static plate  

Microsoft Academic Search

An infinite 3D plate of homogeneous incompressible fluid is considered, with\\u000afinite thickness, together with a 2D infinite homogeneous mass in its centre.\\u000aEinstein equations are exactly solved, in the interior of the 3D mass. The\\u000asolution is joined to the exterior vacuum metric of Taub. Every value for the\\u000a2D mass, positive or negative, allows a perfect junction. Also

A F F Teixeira

2005-01-01

383

Wide-Angle Metal-Plate Optics  

Microsoft Academic Search

The design equations for constrained metal-plate lenses are derived. These lenses prove to have exceptional wide-angle scanning properties. The scanning aberrations are investigated by means of a power series expansion of the phase error. This analysis indicates that the square-law error is a function of lens depth and may be eliminated by the proper choice of lens thickness. It is

J. Ruze

1950-01-01

384

Three-dimensional stress concentrations at elliptic holes in elastic isotropic plates subjected to tensile stress  

Microsoft Academic Search

The through-thickness variations of stress concentration factors along the wall of elliptic holes in finite thickness plates of isotropic materials subjected to remote tensile stress have been systematically analyzed using the finite element method. The three-dimensional stress concentration factor Kt is found to be a function of the thickness to root radius ratio B\\/? and the aspect ratio t (short

Chongmin She; Wanlin Guo

2007-01-01

385

Acceleration of metal plates  

SciTech Connect

High-explosive charges have been used to accelerate stainless steel plates to velocities of 6-7 km/s. A two-stage system has been used in which the first stage is a plane-wave detonating system that accelerates the plate down a short barrel. The second stage consists of a hollow cylindrical charge through which the moving plate passes. After an adjustable delay this charge is detonated on the outer circumference of the entry side of the charge. Flash radiographs and witness plates show no breakup in the first stage but bowing and frequent breakup in the second stage. 6 figs.

Marsh, S.P.; McQueen, R.G.; Tan, T.H.

1989-01-01

386

Plate Motion Calculator  

NSDL National Science Digital Library

This program calculates tectonic plate motion at any location on Earth using one or more plate motion models. The possible plate motion models are GSRM v1.2 (2004), CGPS (2004), HS3-NUVEL1A, REVEL 2000, APKIM2000.0, HS2-NUVEL1A, NUVEL 1A, NUVEL 1, and two models for ITRF2000. Plates or frames are selected from dropdown lists or can be entered by the user. Position coordinates can be entered in geographic coordinates (decimal degrees, or degrees/minutes/seconds) or in WGS84 cartesian XYZ, as either a single point or multiple points.

Estey, Lou

387

CALUTRON FACE PLATE  

DOEpatents

The construction of a removable cover plate for a calutron tank is described. The plate is fabricated of a rectangular frame member to which is welded a bowed or dished plate of thin steel, reinforced with transverse stiffening ribs. When the tank is placed between the poles of a magnet, the plate may be pivoted away from the tank and magnet and is adapted to support the ion separation mechanism secured to its inner side as well as the vacuum load within the tank.

Brobeck, W.M.

1959-08-25

388

Surface preparation and plating  

SciTech Connect

This chapter covers electroplating and electroless nickel plating since coatings of this type play an important role in diamond turning technology. Items to be discussed include preparation of substrates prior to coating, plating defects such as pits and nodules and their influence on optics, the influence of stress in coatings, plating details for copper, gold, silver, and electroless nickel, and the importance of additives and their influence on grain size and structure of deposits. Some comments are made on future challenges that could be presented to the plating community to further improve the quality of coatings applied for diamond turning purposes. 60 references, 8 figures, 9 tables.

Dini, J.W.; Waldrop, F.B.; Reno, R.W.

1982-10-06

389

PLATES WITH OXIDE INSERTS  

DOEpatents

Planar-type fuel assemblies for nuclear reactors are described, particularly those comprising fuel in the oxide form such as thoria and urania. The fuel assembly consists of a plurality of parallel spaced fuel plate mennbers having their longitudinal side edges attached to two parallel supporting side plates, thereby providing coolant flow channels between the opposite faces of adjacent fuel plates. The fuel plates are comprised of a plurality of longitudinally extending tubular sections connected by web portions, the tubular sections being filled with a plurality of pellets of the fuel material and the pellets being thermally bonded to the inside of the tubular section by lead.

West, J.M.; Schumar, J.F.

1958-06-10

390

Thick Film Interference.  

ERIC Educational Resources Information Center

|Discusses why interference effects cannot be seen with a thick film, starting with a review of the origin of interference patterns in thin films. Considers properties of materials in films, properties of the light source, and the nature of light. (JN)|

Trefil, James

1983-01-01

391

An Analysis of Contoured Crystal Resonators Operating in Overtones of Coupled Thickness-Shear and Thickness-Twist.  

National Technical Information Service (NTIS)

A previous treatment of overtone modes in trapped energy resonators is extended to the case of plates with slowly varying thickness. The resulting single scalar equation is applied in the analysis of plano-convex contoured quartz crystal resonators and a ...

H. F. Tiersten R. C. Smythe

1978-01-01

392

An analysis of contoured crystal resonators operating in overtones of coupled thickness-shear and thickness-twist  

Microsoft Academic Search

A previous treatment of overtone modes in trapped energy resonators is extended to the case of plates with slowly varying thickness. The resulting single scalar equation is applied in the analysis of plano-convex contoured quartz crystal resonators and a lumped parameter representation of the admittance, which is valid in the vicinity of a resonance, is obtained. The analysis holds for

H. F. Tiersten; R. C. Smythe

1978-01-01

393

The crustal thickness of Australia  

USGS Publications Warehouse

We investigate the crustal structure of the Australian continent using the temporary broadband stations of the Skippy and Kimba projects and permanent broadband stations. We isolate near-receiver information, in the form of crustal P-to-S conversions, using the receiver function technique. Stacked receiver functions are inverted for S velocity structure using a Genetic Algorithm approach to Receiver Function Inversion (GARFI). From the resulting velocity models we are able to determine the Moho depth and to classify the width of the crust-mantle transition for 65 broadband stations. Using these results and 51 independent estimates of crustal thickness from refraction and reflection profiles, we present a new, improved, map of Moho depth for the Australian continent. The thinnest crust (25 km) occurs in the Archean Yilgarn Craton in Western Australia; the thickest crust (61 km) occurs in Proterozoic central Australia. The average crustal thickness is 38.8 km (standard deviation 6.2 km). Interpolation error estimates are made using kriging and fall into the range 2.5-7.0 km. We find generally good agreement between the depth to the seismologically defined Moho and xenolith-derived estimates of crustal thickness beneath northeastern Australia. However, beneath the Lachlan Fold Belt the estimates are not in agreement, and it is possible that the two techniques are mapping differing parts of a broad Moho transition zone. The Archean cratons of Western Australia appear to have remained largely stable since cratonization, reflected in only slight variation of Moho depth. The largely Proterozoic center of Australia shows relatively thicker crust overall as well as major Moho offsets. We see evidence of the margin of the contact between the Precambrian craton and the Tasman Orogen, referred to as the Tasman Line. Copyright 2000 by the American Geophysical Union.

Clitheroe, G.; Gudmundsson, O.; Kennett, B. L. N.

2000-01-01

394

40 CFR 426.40 - Applicability; description of the plate glass manufacturing subcategory.  

Code of Federal Regulations, 2013 CFR

... Applicability; description of the plate glass manufacturing subcategory. 426.40 Section...EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) GLASS MANUFACTURING POINT SOURCE CATEGORY Plate Glass Manufacturing Subcategory § 426.40...

2013-07-01

395

Improved compression buckling for rectangular composite plates by stiffness tailoring  

NASA Astrophysics Data System (ADS)

Buckling resistance is often a controlling criterion in the design of structural elements. Design concepts that lead to increased buckling loads (or strains) can directly lower the structural cost and/or weight by a number of means. This study quantifies the improvements that can be achieved in compression buckling loads of rectangular composite plates by using a simple stiffness tailoring concept. The approach is to position the unidirectional lamina through the thickness and over the planform of the plate so that the buckling load is increased with no loss in in-plane stiffness or increase in weight. Finite element analyses have been used to determine the effects of tailoring on the buckling load of plates with various boundary conditions, aspect ratios, thicknesses, and membrane stiffnesses. Increases in buckling loads (or strains) of nearly 200 percent over the uniform plate buckling loads are shown possible with this tailoring concept.

Biggers, Sherrill B.; Srinivasan, Sundar

396

Observations of plate martensite in a low carbon steel  

SciTech Connect

It has long been known that there are two predominant morphologies of martensite in steels. These morphologies are currently referred to as plate martensite and lath martensite and are primarily distinguished by the size and shape of individual martensite grains. Plate martensite is typically several microns thick and tens of microns in diameter, while lath martensite is typically less than one-half micron thick, a few microns wide, and tens of microns long. This paper presents evidence of a coarse plate-shaped martensite morphology in a commercial HSLA-100 steel which contains only 0.07% carbon. This morphology was discovered during microstructural characterization of specimens thermally cycled to simulate weld heat affected zones in a steel plate and was reproduced in other specimens subjected to a quench and temper heat treatment.

Fonda, R.W.; Spanos, G.; Vandermeer, R.A. (Naval Research Lab., Washington, DC (United States))

1994-09-15

397

Solderability of environmentally exposed Sn-plated surfaces  

SciTech Connect

Solderability of Class II environmentally exposed Ni-Sn plated Cu substrates was evaluated with 60Sn-40Pb solder. Tin thickness were 10, 50, and 150 {mu}in. The 10 {mu}in. plating gave the smallest solder meniscus rise. A general decrease in contact angle, or increase in wettability, was observed with increasing Sn plating. The environmental exposures retarded the wetting rate and increased the time to maximum wetting, particularly with only 10 {mu}in. of Sn. Although the solderability of the 50 and 150 {mu}in. surfaces were not significantly affected by the test conditions, an intermediate plating thickness of 100 {mu}in. is preferred for processing flexibility. 13 refs., 6 figs., 1 tab.

Hosking, F.M.; Sorensen, N.R.

1990-01-01

398

Lithospheric strength and its relationship to the elastic and seismogenic layer thickness  

Microsoft Academic Search

Plate flexure is a phenomenon that describes how the lithosphere responds to long-term (>105 yr) geological loads. By comparing the flexure in the vicinity of ice, volcano, and sediment loads to predictions based on simple plate models it has been possible to estimate the effective elastic thickness of the lithosphere, Te. In the oceans, Te is the range 2-50 km

A. B. Watts; E. B. Burov

2003-01-01

399

Lithospheric strength and its relationship to the elastic and seismogenic layer thickness  

Microsoft Academic Search

Plate flexure is a phenomenon that describes how the lithosphere responds to long-term (>105 yr) geological loads. By comparing the flexure in the vicinity of ice, volcano, and sediment loads to predictions based on simple plate models it has been possible to estimate the effective elastic thickness of the lithosphere, Te. In the oceans, Te is the range 2–50 km

A. B. Watts; E. B. Burov

2003-01-01

400

The Moving Plates  

NSDL National Science Digital Library

This lesson focuses on relative versus absolute velocity. Students can use a program (must be connected to the internet) to calculate the different types of velocities for different points along plate boundaries. A very brief description of the earth's plates is given, with links to additional information and images. Includes discussion questions.

401

Plate Tectonics with GIS  

Microsoft Academic Search

The concept of Plate Tectonics involves piecing together a wide variety of evidence to build a picture. This includes the location of earthquakes, volcanoes, mountains, fossils, and other paleoclimate data. The theory of Plate Tectonics is driven by information that is attached to a location. Even further, the theory is driven by looking and analyzing all these pieces of information

Nate Ruder

2006-01-01

402

How Do Plates Move?  

NSDL National Science Digital Library

The representation shows the circulation of convection cells in the mantle related to plate movement. A static cross-sectional diagram and accompanying text illustrates the how material heated by the core rises and then sinks when it eventually cools down and attributes this cycle of heating and cooling to tectonic plate movement.

403

Laser-Driven Flyer Plates for Reactive Materials Research  

Microsoft Academic Search

A laser-driven flyer plate apparatus is described for ultrafast spectroscopy of reactive nanomaterial dynamics, that is compatible with fast spectroscopy methods we have already developed. The apparatus uses a standard Nd:YAG laser with aspheric beam shaping optics to produce a flat-top beam, and a vapor-deposited flyer plate array. New diagnostics to measure the flyer plate velocity and its impact with

Hiroki Fujiwara; Kathryn E. Brown; Dana D. Dlott

2009-01-01

404

Could Plate Tectonics Have Operated on Early Mars?  

NASA Astrophysics Data System (ADS)

We consider the likelihood of plate tectonics operating on early Mars and Earth. Crust produced by mid-ocean ridge spreading at the same potential temperature is ~ 3 times thicker on Mars than on Earth; the density contrast between crust and mantle is probably similar on the two planets. Assuming that the radiogenic heat flux is balanced by plate tectonic heat loss, the maximum mechanical boundary layer (MBL) thickness on Mars is twice as great, and plate velocities ~ 4 times slower, for similar size plates. For both planets, subduction is favoured at potential temperatures less than 1500-1600o C, where crustal thicknesses are low. The maximum MBL thickness on the present-day Earth is limited to about 100 km by the dropoff of the thermal boundary layer. The viscosity of this layer is about 1019 Pa s, probably because of the presence of melt. For a similar layer on Mars, the maximum MBL thickness would be ~ 150 km, reducing the potential temperature at which subduction could have occurred to less than ~ 1400o C. Plate velocities are probably limited by viscous drag on the descending slab, which depends on the density contrast, slab length, MBL thickness and mantle viscosity. For a slab length of 300 km, the ancient terrestrial mantle viscosity needs to be < ~ 1020 Pa s to allow the drag-limited plate velocity to remove all the heat. On early Mars, the limiting viscosity is a factor of 4 larger. Whether plate tectonics could have operated on early Mars therefore depends mainly on the viscosity structure of the mantle, which will be strongly affected by the presence or absence of water. If early Mars possessed a low viscosity zone similar to the present-day Earth's, subduction is unlikely to have occurred. In the absence of such a zone, subduction was probably easier to sustain on Mars than on Earth.

Nimmo, F.; Stevenson, D. J.

2000-10-01

405

Heterotrophic plate count methodology in the United States.  

PubMed

In the United States (US), the history of bacterial plate counting (BPC) methods used for water can be traced largely through Standard Methods for the Examination of Water and Wastewater (Standard Methods). The bacterial count method has evolved from the original Standard Methods (1st edition, 1905) plate count which used nutrient gelatin and incubation at 20 degrees C for 48 h, to the HPC method options in the latest edition of Standard Methods that provide greater flexibility of application, depending on the data needs of the water analyst. The use of agar-agar as a gelling agent, replacing gelatin, allowed the use of higher incubation temperatures and resulted in the "body temperature count" (37 degrees C) found in the 3rd through the 8th edition of Standard Methods. The change from 37 degrees C incubation to 35+/-0.5 degrees C accommodated laboratories that did both milk and water analyses. By using a single temperature, fewer incubators were needed. The term "standard plate count" (SPC) first appeared in 1960 (11th edition) along with plate count agar. Incubation at 20 degrees C for the plate count was dropped from the 13th to 15th editions and few changes were made in the SPC method from the 11th edition through the 13th editions. Plate count analysis of bottled waters was included in the 14th edition (1975), calling for incubation at 35+/-0.5 degrees C for 72+/-4 h. Perhaps the most significant changes in plate count methods occurred with the 16th edition (1985). The term heterotrophic plate count replaced the standard plate count, and the spread plate (SP) and membrane filter (MF) methods were added along with new media for pour and spread plates (R2A agar and NWRI agar, both low nutrient) and for the membrane filter method (mHPC medium). The use of low nutrient media, lower incubation temperature, and longer incubation times, results in higher plate count results for most water samples. The options currently available, including low and high nutrient media, incubation temperatures (20 degrees C, 28 degrees C or 35 degrees C), plating methods (pour plate (PP), spread plate and membrane filter) and range of incubation times (24, 48, 72 h and 5-7 days) provide great flexibility in the application of the HPC analysis to drinking water. PMID:15145589

Reasoner, Donald J

2004-05-01

406

Sizing plate heat exchangers  

SciTech Connect

Since their commercial debut in the 1930s, plate heat exchangers have found widespread use in the chemical process industries (CPI). Today, more than two dozen firms market this space-saving and highly efficient type of heat exchanger. One reason for the popularity of plate heat exchangers is that their overall heat-transfer coefficient (U) is superior to that of shell-and-tube heat exchangers [1,2,3,4]. In clean water-to-water service, for example, a shell-and-tube heat exchanger has a U value of 350 Btu/ft[sup 2]-h-F, much lower than the 1,000 of a plate design at the same pressure drop. However, the plate heat exchanger's much higher U values also mean that fouling factors have a much greater effect on calculations of exchanger surface area. The right fouling factor is the key to specifying plate heat exchanger areas correctly.

Kerner, J. (Alberts and Associates, Inc., Philadelphia, PA (United States))

1993-11-01

407

Electroless nickel\\/copper plating as a new bump metallization  

Microsoft Academic Search

An electroless bumping method was developed both for flip chip and TAB applications. Electroless Ni\\/Cu plating is a maskless low-cost approach to bumping directly on aluminum bondpads. An immersion tin layer for coating and soldering is plated on the copper. Due to the high alkalinity (pH>12) of electroless Cu baths, a thick Ni layer of about 7 ?m is required

Rolf Aschenbrenner; Andreas Ostmann; Ute Beutler; Jurgen Simon; H. Reichl

1995-01-01

408

Vibration reduction of floating elastic plates in surface waves  

Microsoft Academic Search

Based on dynamical theories of water waves and dynamics of Mindlin thick plates, the investigation of the wave-induced responses\\u000a and the vibration reduction of an elastic floating plate are presented using the Wiener-Hopf technique. Without regard to\\u000a the case of elastic connector, the calculated results obtained by the present method are in good agreement with those from\\u000a the literature and

Cun-bao Zhao; Jia-zhong Zhang; Wen-hu Huang

2007-01-01

409

Pressure-shear stress wave analysis in plate impact experiments  

Microsoft Academic Search

Numerical results are presented for the combined longitudinal and shear wave propagation in an elastic-viscoplastic solid as it occurs in high strain-rate plate impact experiments. Special attention is paid to the initial stage of the impact experiment and the effects of the specimen thickness, elastic impedances of flyer-anvil plates, and viscoplastic properties of materials on the time to reach a

Wei Tong

1997-01-01

410

Weldability evaluation of high tensile plates using GMAW process  

Microsoft Academic Search

High tensile plates, SAILMA-450 high impact (HI) (yield strength, 45 kg\\/mm2 minimum; ultimate tensile strength, 57 kg\\/mm2 minimum; elongation, 19% minimum; Charpy impact energy 2.0 kg.m at ?20 C minimum) were successfully developed at the Steel\\u000a Authority of India Ltd., up to 32 mm plate thickness. Since then the steel has been extensively used for the fabrication of\\u000a impellers, bridges,

R. Datta; D. Mukerjee; K. L. Rohira; R. Veeraraghavan

1999-01-01

411

Thermoplastic strain of circular sandwich plates on an elastic base  

Microsoft Academic Search

We consider thermomechanical bending of an elastoplastic circular (solid or annular) light-filler sandwich plate resting on\\u000a an elastic base. The hypotheses of broken normal are used to describe the kinematics of the plate stack nonsymmetric along\\u000a the thickness. The base reaction is described by the Winkler model. We obtain the system of equilibrium equations and its\\u000a exact solution in terms

D. V. Leonenko; E. I. Starovoitov

2009-01-01

412

Stability Analysis of Functionally Graded Plates Subject to Thermal Loads  

Microsoft Academic Search

\\u000a Stability analysis of functionally graded ceramic–metal plates under thermal loads is presented using the first order shear\\u000a deformation theory. The effective material properties of the functionally graded plates are assumed to vary through their\\u000a thickness direction according to the power-law distribution of the volume fractions of the constituents. The thermal loads\\u000a are assumed to be uniform, linear and non-linear distribution

Mokhtar Bouazza; A. Tounsi; E. A. Adda-Bedia; A. Megueni

413

Perforation of HY-100 steel plates with long rod projectiles  

Microsoft Academic Search

The authors conducted perforation experiments with 4340 steel, rod projectiles and HY-100 steel, target plates at striking velocities between 80 and 370 m\\/s. Projectiles were machined to nominally 30-mm-diameter and 281-mm-length so they could be launched from a 30-mm-powder gun without sabots. The target plates were rigidly clamped at 305-mm diameter and had a nominal thickness of 10.2 mm. In

S. J. Hanchak; B. S. Altman; M. J. Forrestal

1993-01-01

414

Large scale simulation of plate-like particle suspensions  

Microsoft Academic Search

Colloidal suspensions of plate-like particles are of great technical and theoretical interest. Normally the particle size ranges from 10 nanometers to 10 microns, with aspect ratio (diameter\\/thickness) up to 100. The goal of our research is to study the rheology and microstructure of the suspensions with the presence of hydrodynamic interactions, Brownian motion and inter-particle forces. In our algorithm, plate-like

Qingjun Meng

2004-01-01

415

Nonlinear Vibration of the Cantilever FGM Plate Based on the Third-order Shear Deformation Plate Theory  

NASA Astrophysics Data System (ADS)

The present investigation focuses on the research of the nonlinear vibration of a cantilevered FGMs rectangular plate subjected to the transversal excitation. Materials properties of the constituents are graded in the thickness direction according to a power law distribution and are assumed to be temperature-dependent and vary along the thickness direction. In the framework of the Reddy's Third-order shear deformation plate theory, the governing equations of motion for the cantilever FGMs rectangular plate are derived by using the Hamilton's principle. The thermal effect due to one-dimensional temperature gradient is included in the analysis. The equations of motion can be reduced two-degree-of-freedom nonlinear system under the external excitations using the Galerkin's method. Using numerical method, the control equations are analyzed to obtain the response curves. A detailed parametric study is conducted to show the influences of the material properties on dynamic responses of the nonlinear vibration of the cantilever FGM plate.

Hao, Y. X.; Zhang, W.

2010-05-01

416

Thick brane solutions  

NASA Astrophysics Data System (ADS)

This paper gives a comprehensive review on thick brane solutions and related topics. Such models have attracted much attention from many aspects since the birth of the brane world scenario. In many works, it has been usually assumed that a brane is an infinitely thin object; however, in more general situations, one can no longer assume this. It is also widely considered that more fundamental theories such as string theory would have a minimal length scale. Many multidimensional field theories coupled to gravitation have exact solutions of gravitating topological defects, which can represent our brane world. The inclusion of brane thickness can realize a variety of possible brane world models. Given our understanding, the known solutions can be classified into topologically non-trivial solutions and trivial ones. The former class contains solutions of a single scalar (domain walls), multi-scalar, gauge-Higgs (vortices), Weyl gravity and so on. As an example of the latter class, we consider solutions of two interacting scalar fields. Approaches to obtain cosmological equations in the thick brane world are reviewed. Solutions with spatially extended branes (S-branes) and those with an extra time-like direction are also discussed.

Dzhunushaliev, Vladimir; Folomeev, Vladimir; Minamitsuji, Masato

2010-06-01

417

Plate Tectonics: A Continuous Process  

NSDL National Science Digital Library

This page provides an introduction to plate tectonics for secondary students. Topics include plate motions, the layers of the Earth and oceanic versus continental plates. A set of links provides access to material on the processes of plate tectonics occuring at plate boundaries, zones of movement and instability.

418

Intro to Plate Tectonic Theory  

NSDL National Science Digital Library

This website from PBS provides information about the plate tectonics, the theory that the Earth's outer layer is made up of plates, which have moved throughout time. The four types of plate boundaries are described and illustrated with animations. The first page of plate tectonics also provides a plate tectonics activity and information about related people and discoveries.

2008-05-28

419

Delaminations in composite plates under transverse impact loads - Experimental results  

NASA Astrophysics Data System (ADS)

Tests were performed measuring the locations and geometries of delaminations in Fiberite T300/976 graphite/epoxy, Fiberite IM7/977-2 graphite-toughened epoxy, and ICI APC-2 graphite/PEEK plates subjected to transverse impact loads. The data provide specific information on the effects of impactor velocity, impactor mass, material, thickness of back ply group, difference in fiber orientation between adjacent ply groups, plate thickness, and impactor nose radius. The data were compared to the results of the Finn-Springer model. The model was found to describe the data with reasonable accuracy.

Finn, Scott R.; He, Ye-Fei; Springer, George S.

420

Plating of isolated tobacco mesophyll protoplasts on agar medium  

Microsoft Academic Search

A technique was developed to derive cell and plant clones from isolated mesophyll protoplasts of tobacco. The protoplasts, plated on a fully defined agar medium, divided and grew actively forming visible colonies after one month of culture. Efficiency of colony formation depended on cell density and light condition during incubation. Under standard conditions, 60% of plated protoplasts formed colonies. Upon

Toshiyuki Nagata; Itaru Takebe

1971-01-01

421

Plate Tectonics Jigsaw  

NSDL National Science Digital Library

This activity is a slight variation on an original activity, Discovering Plate Boundaries, developed by Dale Sawyer at Rice University. I made different maps, including more detail in all of the datasets, and used a different map projection, but otherwise the general progression of the activity is the same. More information about jigsaw activities in general can be found in the Jigsaws module. The activity occurs in several sections, which can be completed in one or multiple classes. In the first section, students are divided into "specialist" groups, and each group is given a global map with a single dataset: global seismicity, volcanoes, topography, age of the seafloor, and free-air gravity. Each student is also given a map of plate boundaries. Their task in the specialist group is to become familiar with their dataset and develop categories of plate boundaries based only on their dataset. Each group then presents their results to the class. In the second section, students reorganize into groups with 1-2 of each type of specialist per group. Each new group is given a plate, and they combine their different datasets on that one plate and look for patterns. Again, each plate group presents to the class. The common patterns and connections between the different datasets quickly become apparent, and the final section of the activity involves a short lecture from the instructor about types of plate boundaries and why the common features are generated at those plate boundaries. A follow-up section or class involves using a problem-solving approach to explain the areas that don't "fit" into the typical boundary types - intra-plate volcanism, earthquakes in the Eastern California Shear Zone, etc.

Egger, Anne

422

FEM modeling of adaptive composite structures using a reduced higher-order plate theory via penalty functions  

Microsoft Academic Search

This paper presents a finite element model for analyzing the composite laminates containing the piezoelectrics statistically or dynamically. First, to model the moderately thick laminated plates, a simple higher-order plate theory, which can satisfy the free conditions of transverse shear strains on the top and bottom surfaces of plates, have been adopted. To set up a C0-type FEM scheme, two

H. Fukunaga; N. Hu; G. X. Ren

2001-01-01

423

Conductivity fuel cell collector plate and method of fabrication  

DOEpatents

An improved method of manufacturing a PEM fuel cell collector plate is disclosed. During molding a highly conductive polymer composite is formed having a relatively high polymer concentration along its external surfaces. After molding the polymer rich layer is removed from the land areas by machining, grinding or similar process. This layer removal results in increased overall conductivity of the molded collector plate. The polymer rich surface remains in the collector plate channels, providing increased mechanical strength and other benefits to the channels. The improved method also permits greater mold cavity thickness providing a number of advantages during the molding process.

Braun, James C. (Juno Beach, FL)

2002-01-01

424

High loading uranium plate  

SciTech Connect

Two embodiments of a high uranium fuel plate are disclosed which contain a meat comprising structured uranium compound confined between a pari of diffusion bonded ductile metal cladding plates uniformly covering the meat, the meat hiving a uniform high fuel loading comprising a content of uranium compound greater than about 45 Vol. % at a porosity not greater than about 10 Vol. %. In a first embodiment, the meat is a plurality of parallel wires of uranium compound. In a second embodiment, the meat is a dispersion compact containing uranium compound. The fuel plates are fabricated by a hot isostatic pressing process.

Wiencek, T.C.; Domagala, R.F.; Thresh, H.R.

1990-10-16

425

Plate Tectonics at Work  

NSDL National Science Digital Library

This is a brief description of the results of plate movement according to the Theory of Plate Tectonics. It explains how divergence at the mid-ocean ridges accounts for the discoveries of Harry Hess. The site also refers to the invention of the magnetometer and the discovery of the young age of the ocean floor basalt. It concludes that these are the kinds of discoveries and thinking that ultimately led to the development of the theory of plate tectonics and that in just a few decades, have greatly changed our view of and notions about our planet and the sciences that attempt to explain its existence and development.

426

Mountains and Moving Plates  

NSDL National Science Digital Library

These are the lecture notes for a class on plate tectonics and mountain building which is taught at the University of Wisconsin-Madison. The course describes the connections between the earth's tectonic plates, earthquakes, and its many mountain ranges. Topics include basic geography, the structure of the earth's interior, the relationships between the seismic cycle, volcanism, and plate movements, erosion of mountains, and mass wasting. Links are provided to additional resources, including aerial photos of geologic features, an interactive map of geology and topography of the United States, and a glossary.

427

Mode selection of guided waves for ultrasonic inspection of gas pipelines with thick coating  

Microsoft Academic Search

Mode selection of guided waves in an elastic steel plate with thick coating layer has been studied here. Effect of both thick elastic coating and damping of the coating layer on the dispersion and mode shapes has been investigated and modes that are less affected by elastic coating and damping have been identified. For modeling the viscoelastic behavior of the

E. Pan; J. Rogers; S. K. Datta; A. H. Shah

1999-01-01

428

A unified theory for laminated plates  

NASA Astrophysics Data System (ADS)

A literature survey on plate and beam theories show how the advent of the finite element method and the variational method circa 1940 have been a great stimulant for the research in this field. The initial thin plate formulation has been incrementally expanded to treat the isotropic thick plate, the anisotropic single layer, and then laminated plates. It appears however that current formulations still fall into one of two categories: (1) The formulation is tailored for a specific laminate and/or loading case; (2) or the formulation is too complicated to be of practical relevance. In this work a new unifying approach to laminated plate formulation is presented. All laminated plates, including sandwich panels, subjected to any surface load and with any boundary conditions are treated within a single model. In addition, the fundamental behavior of the plate as a two-dimensional structural element is explained. The novel idea is the introduction of fundamental state solutions, which are analytical far field stress and strain solutions of the laminated plate subjected to a set of hierarchical primary loads, the fundamental loads. These loads are carefully selected to form a basis of the load space, and corresponding solutions are superposed to obtain extremely accurate predictions of the three dimensional solution. six,y,z =aklx,y sikl z where i = 1,..., 6; 1=1,...,l max is a substate of the kth fundamental state k=1,2,3,... Typically, a fundamental state solution is expressed as a through-thickness function (z), while the amplitudes of each fundamental load are found from two dimensional finite element solution as a function of in-plane coordinates (x,y). Three major contributions are produced in this work: (1) A complete calibration of the plate as a two-dimensional structure is performed with pure bending and constant shear fundamental states. (2) There are four independent ways to apply a constant shear resultant on a plate, as opposed to one for a beam. This makes it impossible to define a unique 2 x 2 transverse shear stiffness matrix. Therefore the traditional problem of the shear correction factor loses all relevance. It is however shown that an explicit transverse constitutive relation can be obtained for isotropic-layered laminates or single-layers. (3) Higher accuracy, three-dimensional solutions are obtained using a two-dimensional finite element model with a complexity level (degrees of freedom) similar to the Reissner-Mindlin plate. The proof of concept is realized using Pagano solution for rectangular plates under sinusoidal load, for a sandwich panel. Additional comparisons are also performed for four and six-layer symmetric and antisymmetric laminates, between the new plate theory results and full three-dimensional finite element solutions.

Guiamatsia Tafeuvoukeng, Irene

429

Shear buckling response of tailored, rectangular, composite plates  

NASA Astrophysics Data System (ADS)

The concept of stiffness tailoring for improved shear buckling resistance of rectangular composite plates is investigated analytically. The tailoring involves only the redistribution of the given material with given orientations to create beneficial stiffening patterns across the planform of the plate. The resulting local nonuniformities in thickness and membrane and bending stiffness combine to change the buckling response of the plate. The weight and average membrane shear stiffness are essentially unaffected by the tailoring. Practical limitations on the degree to which the tailoring may be carried out are shown to govern most designs. Improvements in the shear buckling load on the order of 50 percent are shown possible with monolithic tailoring. Tailored sandwich concepts, in which a light-weight core material is added to keep both plate surfaces flat, can produce improvements well over 100 percent in specific buckling loads compared with uniform composite plates.

Biggers, Sherrill B.; Pageau, Stephane S.

1993-04-01

430

Dynamic response of elastoplastic Mindlin plate by mode superposition method  

NASA Astrophysics Data System (ADS)

The dynamic elastic-plastic response of a thick circular plate has been investigated by using the Mindlin plate theory. The normal modes and frequencies of free vibrations of an 'assumed elastic' plate are used to transform the space displacements into modal generalized displacements. In each time subinterval the nonlinear terms are grouped together with external loads and the pseudoloads so obtained are interpolated by a quadratic polynomial of time and are determined by an iterative procedure. Numerical results are obtained for simply supported and clamped plates subjected to different type of pulse loads (rectangular and two types of triangular pulses). The influence of the pulse shape, pulse duration, and inelastic strains on the plate response is considered.

Manoach, E.

1993-03-01

431

An experimental study of normal and oblique impact of hard-core projectile on single and layered plates  

Microsoft Academic Search

An experimental study of the normal and oblique impact of armour-piercing projectiles on single and layered plates of mild steel, RHA steel and aluminium is presented. The projectiles were fired at an impact velocity of ?800–880 m s?1. The plate thickness varied in the range 4.7–40 mm and the ratio of the plate thickness to the diameter of the projectile

N. K. Gupta; V. Madhu

1997-01-01

432

Modeling Spallation Damage in Laser Driven Flyer Plate Experiments  

Microsoft Academic Search

The TRIDENT laser at Los Alamos has been used to drive small plate impact experiments. Flyers are typically 8 mm in diameter and 0.1 to 1.0 mm thick, while the targets are 10 mm in diameters and 0.2 to 2.0 mm thick. The sample materials are polycrystalline copper and copper composed of large columnar grains. The latter samples reveal information

Davis Tonks; Dennis Paisley; Pedro Peralta; Scott Greenfield; Darrin Byler; Shengnian Luo; Damian Swift; Aaron Koskelo

2007-01-01

433

Extensional edge modes in elastic plates and shells.  

PubMed

The recently discovered undamped localized mode at the end of an elastic strip is demonstrated to be particularly relevant in the plane stress setting, where it exists for the Poisson ratio 0.29. This paper also emphasizes the difference between low-frequency edge modes, typically characterized by low variation across the plate (or shell) thickness, and high-frequency edge modes, whose natural frequencies are of the order of thickness resonance frequencies. PMID:19206837

Kaplunov, J; Pichugin, A V; Zernov, V

2009-02-01

434

Nonlinear Bending Response of Functionally Graded Plates Under Thermal Loads  

Microsoft Academic Search

Nonlinear bending analysis of functionally graded plates subjected to uniform pressure and thermal loads is investigated using a 3-D finite element method. Material properties are varied continuously in the thickness direction according to a simple power law distribution. A three-dimensional solid element is used for more accurate modeling of material properties and temperature field in the thickness direction. The Green–Lagrange

Kyung-Su Na; Ji-Hwan Kim

2006-01-01

435

Development status of thick film photoresist for semiconductor packaging  

NASA Astrophysics Data System (ADS)

In recent years, the demand of thick film photoresists for both copper metal posts and solder bump has been rising for Wafer Level Chip Size Package (WL-CSP) applications. The polymerizing negative tone photoresist, typified by Dry-film photoresist, for metal post applications is currently the mainstream method, but difficulty in removal, thickness selectivity, scaling of chip size and high definition requirements has made the development of a positive tone photoresist for thick film application a necessity. However, the sensitization of a conventional DNQ positive tone photoresist system was difficult due to the nature of the reaction mechanism. In order to meet these requirements, a study was made with a new approach with a positive tone chemically amplified photoresist system, and will be explained in detail in this paper. In general, DNQ type thick photoresist for plating process is developed from the positive tone photoresist platform for semiconductor application through optimization of resist composition and improvement of cracking during the plating process through addition of plasticizers. Inherent performance or compatibility issues with the conventional plasticizer in positive tone chemically amplified photoresist have lead to the development of plasticizer with protecting group. This modification of composition has improved the phtoresist for cracks and swelling of bumps after plating. This is the first chemically amplified photo resist designed for use in the consumer product manufacturing industry.

Misumi, Koichi; Saito, Koji; Obiya, Hiroyuki

2005-05-01

436

Thick Lens Model  

NSDL National Science Digital Library

The EJS Thick Lens model allows the user to simulate a lens (mirror) by adjusting the physical properties of a transparent (reflecting) object and observing the object's effect on a beam of light.  The user can adjust the concavity of the sides, the index of refraction and its environment, and the height and width of the object as well as the size of the incident light and the horizontal position of the transparent object.  Spherical aberration can be observed at large angles. You can examine and modify this simulation if you have Ejs installed by right-clicking within the plot and selecting "Open Ejs Model" from the pop-up menu item. Ejs Thiuck Lens model was created using the Easy Java Simulations (Ejs) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the ejs_ntnu_optics_ThickLens.jar file will run the program if Java is installed. Ejs is a part of the Open Source Physics Project and is designed to make it easier to access, modify, and generate computer models. Additional Ejs models for optics are available. They can be found by searching ComPADRE for Open Source Physics, OSP, or Ejs.

Hwang, Fu-Kwun

2008-11-02

437

Paleomagnetism and Plate Tectonics.  

National Technical Information Service (NTIS)

Paleomagnetism and plate tectonics are combined in a new procedure for producing paleogeographic reconstructions of the evolution of present day world geography from proto-continents. For each geologic epoch, the continents are first subjected to rotation...

J. Francheteau

1970-01-01

438

Plate Thermometer: Practical Aspects.  

National Technical Information Service (NTIS)

Fire resistance furnaces have different thermal properties and expose test specimens to different heating conditions if controlled by temperature readings by ordinary TC's. The so called Plate Thermometer PT has therefore been introduced. Several investig...

U. Wickstroem

1997-01-01

439

My Plate Food Guide  

MedlinePLUS

... health problems like heart disease, diabetes, and even depression. Aim to get at least 60 minutes of moderate to vigorous exercise every day. Practical Advice on Eating Right and Exercise The USDA's MyPlate website offers lots of ...

440

Plate Tectonics Learning Module  

NSDL National Science Digital Library

This plate tectonics unit was designed to be used with a college course in physical geography. Subject matter covered includes: the development of the theory including Wegener's Continental Drift Hypothesis and the existence of Pangaea, Harry Hess and his work on sea-floor spreading, and the final theory. It points out that global features such as deep oceanic trenches, mid-ocean ridges, volcanic activity, and the location of earthquake epicenters can now be related to the story of plate tectonics, since most geological activity occurs along plate boundaries. Divergent, convergent and transform plate boundaries are discussed in detail. This module contains a study guide and outline notes, study questions, and practice quizzes. One feature of the module is a web exploration section with links to twelve outside sites that augment the instruction.

Haberlin, Rita

441

Quarter Wave Plate Program  

NSDL National Science Digital Library

The Quarter Wave Plate program displays the effect of a quarter wave plate on an incident electromagnetic wave. The default electromagnetic wave is plane polarized but this polarization can be changed by specifying the components of the waveâs Jones vector using the input fields. The slider can be used to rotate the quarter wave plate to change its orientation. Quarter Wave Plate is an Open Source Physics program written for the teaching of optics. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the optics_quarterwave.jar file will run the program if Java is installed. Other optics programs are also available. They can be found by searching ComPADRE for Open Source Physics, OSP, or Optics.

Simov, Kiril; Christian, Wolfgang

2008-05-20

442

Half Wave Plate Program  

NSDL National Science Digital Library

The Half Wave Plate program displays the effect of a half wave plate on an incident electromagnetic wave. The default electromagnetic wave is plane polarized but this polarization can be changed by specifying the components of the waveâs Jones vector using the input fields. The slider can be used to rotate the half wave plate to change its orientation. Half Wave Plate is an Open Source Physics program written for the teaching of optics. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the optics_halfwave.jar file will run the program if Java is installed. Other optics programs are also available. They can be found by searching ComPADRE for Open Source Physics, OSP, or Optics.

Simov, Kiril; Christian, Wolfgang

2008-05-20

443

Seismology and Plate Tectonics  

Microsoft Academic Search

This introduction to seismological theory and the principles of plate tectonics also develops a practical approach to the interpretation of seismograms for physicists and mathematicians as well as geologists.

David Gubbins

1990-01-01

444

Tectonic Plate Movement.  

ERIC Educational Resources Information Center

Presents an activity that employs movement to enable students to understand concepts related to plate tectonics. Argues that movement brings topics to life in a concrete way and helps children retain knowledge. (DDR)

Landalf, Helen

1998-01-01

445

Polygonal Fresnel zone plates  

NASA Astrophysics Data System (ADS)

The performance of Fresnel zone plates having a polygonal boundary between zones has been studied. The contribution of the complex amplitude of each zone is calculated analytically and numerically solved. The case of a continuous phase plate is considered as the limit case in performance for each polygonal shape. This performance is compared with respect to the circular case. Also four different methods to define a polygonal FZP having discrete phase shift are analyzed and compared.

Alda, Javier; González, Francisco Javier

2009-08-01

446

Plate Tectonics: An Introduction  

NSDL National Science Digital Library

In the early 1900s, most geologists thought that Earth's appearance, including the arrangement of the continents, had changed little since its formation. This video segment describes the impact the theory of plate tectonics has had on our understanding of Earth's geological history, and provides a brief overview of what is currently known about the Earth's tectonic plates and their motions. The segment is two minutes twenty-one seconds in length. A background essay and list of discussion questions are also provided.

447

Plate Rolling Modeling at Mill 5000 of OJSC ``Magnitogorsk Iron and Steel'' for Analysis and Optimization of Temperature Rates  

NASA Astrophysics Data System (ADS)

Modeling of strip deflected mode and thermal state in rolling is an integral part of the technology and perspective rolling-mill machinery such as plate mill 5000 of the OJSC ``Magnitogorsk Iron and Steel''. To comprehend metal behavior in the deformation zone in the rough passes during plate rolling it is essential to assess the impact of various temperature factors on variations in field of stress and strain intensities as well as temperature fields in deformation. To do such researches in consideration of various software products and adequate results one of the most effective methods nowadays is regarded as the method of finite elements. The research shows modeling of roughing rolling of a pipe steel sheet with strength category X80 according to standard API-5L. In the research of the metal deflected mode software product DEFORM 2D has been used for the isothermal and nonisothermic process. The mathematical modeling allows revealing the impact of temperature field on the metal deflected mode in the rough passes in plate rolling. Supposedly, it is deformation heating that can have more impact on the ingot temperature profile in the finishing passes in controlled rolling of the pipe steel grades. It is defined by high percent reduction, rolling speeds; more area of heat exchange surface; less thickness and lower temperature of rolling. The results can be used to develop efficient modes of plate rolling of the pipe steels.

Salganik, V.; Shmakov, A.; Pesin, A.; Pustovoytov, D.

2010-06-01

448

Metal Thickness Measurements Using Radiography.  

National Technical Information Service (NTIS)

The present invention relates broadly to a radiographic inspection technique, and in particular to a metal thickness measurement method using radiography. The localized areas wherein the effective metal thickness is less than the minimum that is required ...

P. M. Achrekar

1986-01-01

449

Effectiveness of nickel plating in inhibiting atmospheric corrosion of copper alloy contacts  

SciTech Connect

A series of tests was run to determine the effect of Ni plating thickness on connector contact resistance. Copper coupons were plated with an electrolytic nickel strike followed by electroless nickel to produce Ni layers of 10, 20, 55 and 100 {micro}in. The coupons were then exposed to a simulated industrial environment. Pore corrosion was observed after the exposure, which correlated with Ni thickness. In a second series of tests, beryllium-copper four-tine contacts with 50 {micro}in of gold plate over electrolytic nickel strike/electroless-nickel plates of varying thickness were exposed the same corrosive environment. Contact resistance of mated pairs was monitored over a two-month period. The degradation in contact resistance correlated with the Ni thickness used in the connectors.

Ernest, T.; Sorensen, R.; Guilinger, T.

1997-12-31

450

Bifurcation of the Thermo-Elastic Deformation of an Asymmetric Plate (Preprint).  

National Technical Information Service (NTIS)

The deformation of a thin flat elastic plate typically exhibits classic elastic bifurcation behavior when subjected to a through-thickness- graded thermal, or other inelastic, strain. For small strain there is a unique solution to the governing equations,...

G. Jefferson T. Parthasarathy

2007-01-01

451

Optimization of Microchannel Plate Multipliers for Tracking Minimum-Ionizing Particles.  

National Technical Information Service (NTIS)

The progress in development of special Microchannel Plates for particle tracking is reported. The requirements of (1) high spatial resolution; (2) high density of information; and (3) rate capability were found to be satisfied in a thick Microchannel Plat...

K. Oba P. Rehak D. Potter

1981-01-01

452

Acceptance criteria for thick film resistors  

SciTech Connect

The goal of this work was to determine the lot-to-lot consistency of thick film resistors. Also, incoming inspection procedures for inks were evaluated. The DuPont BIROX 1400 series resistors were found to be very consistent and reproducible. Recommendations are that material be bought on the standard DuPont certifications. A testing program of ink properties was recommended at Bendix to establish a material data base.

Nordstrom, T.V.

1980-08-01

453

Metal thickness measurements using radiography  

Microsoft Academic Search

The present invention relates broadly to a radiographic inspection technique, and in particular to a metal thickness measurement method using radiography. The localized areas wherein the effective metal thickness is less than the minimum that is required for radiation shielding and which can render a shielding enclosure functionless, is readily determined. The invention comprises a process for assuring metal thickness

P. M. Achrekar

1986-01-01

454

Caribbean plate interactions  

SciTech Connect

Vector analysis of plate motions, derived from studies of Atlantic magnetic lineations and fracture zone trends, indicates the following relative movements between the Caribbean, North American, and South American Plates. (1) During Early Jurassic to Early Cretaceous, the North American Plate moved 1900 km westward and 900 km northward relative to the South American Plate. A broad zone including the Caribbean region, i.e., the zone between the North and South America Plates, was a site of left-lateral shear and north-south extension. (2) During Early Cretaceous to Late Cretaceous, the North American Mate moved an additional 1200 km westward relative to South America across this zone. (3) During Late Cretaceous to the end of the Eocene, the North American Plate moved 200 km westward and 400 km northward relative to the South American Plate. (4) From the end of the Eocene to near the end of the Miocene, North America converged on South America some 200 km and moved 100 km eastward relative to it. Through the Mesozoic and earliest Tertiary history of the Caribbean, the region was a shear zone within which left-lateral displacement exceeded 3000 km and north-south extension exceeded 1300 km. In regard to time, 80% of the history of the Caribbean region is one of north-south extension and left-lateral shear. In terms of space, 97% of the shear is left-lateral and the ratio of divergence versus convergence is 7 to 1. Thus, characterizing the Caribbean region, and the Atlantic to its east, as a zone of north-south extension and left-lateral shear, is a fair generalization.

Ball, M. (Geological Survey, Denver, CO (United States))

1993-02-01

455

An Introduction to Plate Tectonics  

NSDL National Science Digital Library

This page is a brief introduction to plate tectonics. It starts with a discussion of the evolution of the theory of plate tectonics and the arguments supporting it. It then discusses the processes associated with tectonics and the types of plate boundaries: divergent, convergent and transform boundaries. It concludes with a discussion of the current hypotheses of what causes plates to move.

456

Ultrasonic butt welding of aluminium, anticorrosive aluminium and copper plate specimens  

Microsoft Academic Search

Ultrasonic butt welding of thick metal plate specimens is studied. Welding specimens used are aluminium, anticorrosive aluminium, and copper plates of 6-mm thickness. These welding specimens are successfully joined end to end with specimen strength of about 100 MPa (pure aluminium) or 250 MPa (anticorrosive aluminium) using 26-kHz or 19-kHz butt welding equipment. An ultrasonic vibration source of 19 kHz

Jiromaru TSUJINO; Tetsugi UEOKA

1988-01-01

457

India Plate Motion, Intraplate deformation and Plate Boundary Processes (Invited)  

NASA Astrophysics Data System (ADS)

We use GPS-measured velocities to geodetically constrain India plate motion, intraplate strain, and examine plate boundary deformation and plate interactions around the India plate. Our solution includes 15 GPS velocities from continuously recording stations from within the stable India plate interior that are used to estimate angular velocity of the India plate with respect to its neighbors. We test a two-plate India system divided along the topographically prominent Narmada Son Lineament and find this scenario to be significant only to 89%. Dense station coverage along the Himalayan range front allows us to rigorously test boundary parameterizations and develop a preferred plate boundary model. In our preferred model the Himalayan Range Front accumulates ~50% of the India-Eurasia convergence with as much as 18 mm/yr of slip accumulation along some segments. We compare earthquake slip vector orientations with predicted divergence directions from our preferred model along the India-Somalia plate boundary. We see good agreement between predicted plate directions from our preferred model and the seismological data. Deviations between our model and the slip vectors highlight areas of diffuse oceanic deformation along the plate boundary. We estimate convergence vectors for the relative plate pairs along the Sumatra subduction zone. We test for the transition between Australian plate convergence and India plate convergence along the Sumatra subduction zone and refine the estimated motion of the Burman sliver plate.

Apel, E. V.; Burgmann, R.; Banerjee, P.

2010-12-01

458

Modeling of composite beams and plates for static and dynamic analysis  

NASA Astrophysics Data System (ADS)

A rigorous theory and the corresponding computational algorithms were developed for through-the-thickness analysis of composite plates. This type of analysis is needed in order to find the elastic stiffness constants of a plate. Additionally, the analysis is used to post-process the resulting plate solution in order to find approximate three-dimensional displacement, strain, and stress distributions throughout the plate. It was decided that the variational-asymptotical method (VAM) would serve as a suitable framework in which to solve these types of problems. Work during this reporting period has progressed along two lines: (1) further evaluation of neo-classical plate theory (NCPT) as applied to shear-coupled laminates; and (2) continued modeling of plates with nonuniform thickness.

Hodges, Dewey H.

1992-07-01

459

BEPLATE emdash simulation of electrochemical plating  

SciTech Connect

BEPLATE is a FORTRAN code that uses the boundary element method to simulate the electrochemical plating of material on parts, primarily rotating axisymmetric parts. A boundary element technique is used to solve for the local current density and thus the plating rate on the part, which is used to calculate the growth in the plated layer over a user-specified time step. The surface is moved to reflect this growth, and the new surface is used to generate the local current density. This cycle is repeated until the final time specified by the analyst, producing the final plated thickness. BEPLATE includes models for the polarization effects at both the part (cathode) and anode and allows the use of symmetry planes and nonconducting shields. For electroplating simulations, the part shape is normally assumed to be axisymmetric with a centerline along the z-axis. More general part shapes can be analyzed by BEPLATE if the surface growth simulation is not needed. In either case, the shield, anode, and tank geometries are not restricted to specific shapes. This report includes the information required to run BEPLATE, specifically, a brief description of the BEPLATE system including hardware and software requirements, a description of the complete simulation process, discussion of rules for generating models, and additional reference material. This system of codes consists of model generators (PIGS or PATRAN), input processor (BEPIN), the simulation code (BEPLATE) and postprocessing codes (PATRAN or CONPLOT).

Giles, G.E. (Oak Ridge K-25 Site, TN (USA)); Gray, L.J. (Oak Ridge National Lab., TN (USA)); Bullock, J.S. IV (Oak Ridge Y-12 Plant, TN (USA))

1990-09-01

460

Piezoelectric Energy Harvesting with a Clamped Circular Plate: Experimental Study  

Microsoft Academic Search

In a companion article, a model for a clamped circular unimorph piezoelectric plate has been developed for the purpose of analyzing the influence of geometric design parameters and electrode configuration on the amount of electrical energy that can be harvested from an applied pressure source. It has been shown that the ratio of layer thickness (piezoelectric layer to substrate layer)

Sunghwan Kim; William W. Clark; Qing-Ming Wang

2005-01-01

461

Measurements with a 35 psec gate time microchannel plate camera  

SciTech Connect

Measurements of the x-ray gate time of 0.2 mm thick microchannel plates with an L/D aspect ratio of 20 as opposed to the more usual L/D=40, demonstrate that gate times of 35 ps can be achieved. Good agreement with time dependent modelling is demonstrated. 7 refs., 4 figs., 2 tabs.

Bell, P.E.; Kilkenny, J.D.; Hanks, R.; Landen, O.

1990-07-01

462

Autocatalytic electroless nickel-boron plating on light alloys  

Microsoft Academic Search

Light alloys are more and more widely used, notably in aeronautics and the car industry. To improve their superficial properties, they can be covered with a hard and wear resistant protective layer. In this article, we examine the possibility of depositing a thick autocatalytic electroless Ni–B plating on aluminium alloys. We propose an alkaline bath containing sodium borohydride as the

F Delaunois; J. P Petitjean; P Lienard; M Jacob-Duliere

2000-01-01

463

Effect of a Retarding Plate on White Light Interferometer Fringes  

Microsoft Academic Search

White-light fringes given by the Michelson's interferometer are usually but few in number, and are seen as straight bands. But the mere introduction of a thick glass plate with plane-parallel sides in the path of one of the interfering beams is shown to bring into view literally hundreds of them in the form of circular rings. Any attempt at partially

Nihal Karan Sethi

1924-01-01

464

Trapped Energy Quartz Crystal Resonator on Wedge-Shaped Plate.  

National Technical Information Service (NTIS)

Based upon the general relation of dispersion for a quartz plate of doubly rotated cut, an analytical model is presented. It describes the modes shapes of a resonator exhibiting a linear thickness variation along in-plane directions and is only submitted ...

R. Bourquin

1992-01-01

465

Optimization of plasma arc cutting of mild steel thin plates  

Microsoft Academic Search

Summary form only given: Plasma arc cutting (PAC) is a widely used industrial process for the cutting of different types of metals in several operating conditions. PAC is considered a challenging technology compared to its main competitors: oxy-fuel and laser cutting, in particular for cutting of mild steel in the thickness range 8-40 mm. PAC of mild steel thin plates

V. Colombo; A. Concetti; E. Ghedini; S. Dallavalle; R. Fazzioli; M. Vancini

2008-01-01

466

An oceanic flood basalt province within the Caribbean plate  

Microsoft Academic Search

The thick oceanic crust of the Caribbean plate appears to be the tectonized remnant of an eastern Pacific oceanic plateau that has been inserted between North and South America. The emplacement of the plateau into its present position has resulted in the obduction and exposure of its margins, providing an opportunity to study the age relations, internal structure and compositional

C. W. Sinton; R. A. Duncan; M. Storey; J. Lewis; J. J. Estrada

1998-01-01

467

Limb lengthening over plate  

PubMed Central

Background: The limb lengthening over plate eliminates the associated risk of infection with limb lengthening over intramedullary nail. We present our experience of limb lengthening in 15 patients with a plate fixed on the proximal segment, followed by corticotomy and application of external fixator. Materials and Methods: 15 patients (7 females, 8 males) were included in this consecutive series. The average age was 18.1 years (range 8–35 years). Fifteen tibiae and one femur were lengthened in 15 patients. Lengthening was achieved at 1 mm/day followed by distal segment fixation with three or four screws on reaching the target length. Results: The preoperative target length was successfully achieved in all patients at a mean of 4.1 cm (range 1.8–6.5 cm). The mean duration of external fixation was 75.3 days (range 33–116 days) with the mean external fixation index at 19.2 days/cm (range 10.0–38.3 days/cm). One patient suffered deep infection up to the plate, three patients had mild procurvatum deformities, and one patient developed mild tendo achilles contracture. Conclusion: Lengthening over a plate allows early removal of external fixator and eliminates the risk of creating deep intramedullary infection as with lengthening over nail. Lengthening over plate is also applicable to children with open physis.

Kulkarni, Ruta; Singh, Nishant; Kulkarni, Govind S; Kulkarni, Milind; Kulkarni, Sunil; Kulkarni, Vidisha

2012-01-01

468

Locking plate construct for femoral shaft fractures in skeletally immature patients  

Microsoft Academic Search

Different methods of internal fixation are used in the treatment of femoral shaft fractures. Results of locked plate fixation in adults have been encouraging. A locking plate construct with a standard broad Dynamic Compression Plate (DCP) and 4.5 mm nuts was used in the treatment of femoral shaft fractures in 15 skeletally immature patients. There were 12 boys and three

Akram H AMMAD

469

Development of hybrid MSGC with a conductive capillary plate  

NASA Astrophysics Data System (ADS)

An intermediate electron multiplier for a MicroStrip Gas Chamber has been developed using a capillary plate. Our purpose was to develop a capillary plate as an intermediate electron multiplier able to be steadily operated under a medium gain of about one hundred and under a high counting rate. The capillary plate used here consists of a bundle of fine glass capillaries each with a diameter of 100 micrometers and a thickness of 1 mm, and has a 9.5 X 9 cm2 detection area and a 57% opening aperture ratio. In order to avoid the charge-up effect on the surfaces of the capillaries, some conductivity was added on the capillaries surfaces, and consequently about a 40 M(Omega) resistivity appeared between both sides of the plate. The conductivity dramatically improved the plates performance: the capillary plate was operated stable with counting rates up to 105 cps/mm2 and no decrease in the gas gain was observed. The capillary plate sufficiently satisfies the requirements for a pre-amplification device for an MSGC. In this paper, a 2D MSGC combined with the above conductive capillary plate was examined, and found to achieve stable operation with a sufficient gain under a high counting rate with no discharge problems.

Nishi, Yuji; Tanimori, Toru; Ochi, Atsuhiko; Nishi, Yasuro; Toyokawa, Hidenori

1999-10-01

470

Tectonic Plates, Earthquakes, and Volcanoes  

NSDL National Science Digital Library

According to theory of plate tectonics, Earth is an active planet -- its surface is composed of many individual plates that move and interact, constantly changing and reshaping Earth's outer layer. Volcanoes and earthquakes both result from the movement of tectonic plates. This interactive feature shows the relationship between earthquakes and volcanoes and the boundaries of tectonic plates. By clicking on a map, viewers can superimpose the locations of plate boundaries, volcanoes and earthquakes.

2011-05-12

471

The Number of Tectonic Plates  

NASA Astrophysics Data System (ADS)

The number of tectonic plates on Earth described in the literature has expanded greatly since the early days of plate tectonics, when only a dozen or so plates were considered in global models of present day plate motions. Recently, with new techniques of more accurate earthquake epicenter locations, modern ways of measuring ocean bathymetry using swath mapping, the use of space based geodetic techniques &c, there has been a huge growth in the number of plates thought to exist. Bird (2003) proposed 52 plates, many of which were delineated on the basis of earthquake locations. Because of the pattern of areas of these plates, he suggested that there should be more small plates than he could identify. In this paper, I gather together publications that have proposed additional plates and discuss the new area arrangement which has been produced by the addition of these 23 new plates to Bird's catalogue. In addition I have measured the areas of the very small plates along the San Andreas fault identified by Bird and Rosenstock (1984) and added these 17 plates to the list as well as five plates proposed by Meade and Hager (2005). Sorting the plates by size allows us to investigate how size varies as a function of order. There are several changes of slope in the log-log plots of plate number (largest to smallest) against plate linear dimension. One set of relatively small plates shows a negative slope of -2.5, the same slope that has been found by modelling studies of two-dimensional structures such as rifted margins as well as three dimensional fragmentation models. Plates were characterized by what types of boundary they had. On looking at boundary type as a function of plate order, there seems to be no obvious pattern apart from what has been caused by non-uniform study of Earth's plate tectonic boundaries.

Harrison, C. G.

2011-12-01

472

A method for modeling the local and global buckling of delaminated composite plates  

Microsoft Academic Search

An analytical methodology is presented for predicting the buckling initiation of delaminated composite plates. Both global and local sublaminate buckling deformation modes are predicted for rectangular plates of any thickness. The global behavior of the delamination zone is accounted for by summing the individual stiffness contributions of each sublaminate constituting the delamination zone. This allows for the delamination zone to

Hyonny Kim; Keith T. Kedward

1999-01-01

473

Elasticoplastic bending of rectangular plates reinforced with fibers of constant cross section  

Microsoft Academic Search

The problem on the elastoplastic transverse bending of Kirchhoff plates of variable thickness reinforced with fibers of constant cross section is formulated and its qualitative analysis is performed. An analytical solution to the problem is constructed in the case of cylindrical bending, and, by using the Bubnov-Galerkin method, an approximate solution for a rectangular plate is obtained. Based on calculations

Yu. V. Nemirovskii; A. P. Yankovskii

2005-01-01

474

Theory of four-point alternating current potential drop measurements on conductive plates  

Microsoft Academic Search

Measurements of alternating current potential drop (ACPD) made at the surface of a conductive plate can be used to determine, non-destructively, the parameters of the plate such as its thickness, electrical conductivity and linear effective magnetic permeability. In order to invert the measured potential drop to yield values for these parameters, a theoretical model is needed. In this work, closed

John R. Bowler; Nicola Bowler

2007-01-01

475

Characteristics of silver-plated film on the second wire bondability  

Microsoft Academic Search

Strong bond between the gold wire and the silver-plated leadframe is significantly crucial for maintaining either bondability or reliability during IC (integrated circuit) manufacturing process and IC application in the fields. This study investigated the surface and grain structure of the silver-plated film on the copper leadframe in terms of surface roughness test by atomic force microscopy (AFM), thickness, hardness

T. Y. Lin; K. L. Davison; W. S. Leong; S. Chua; O. Robin; Y. F. Yao; J. S. Pan; J. W. Chai; K. C. Toh; W. C. Tjiu

2002-01-01

476

Buckling of laminated sandwich plates with soft core based on an improved higher order zigzag theory  

Microsoft Academic Search

An improved higher order zigzag theory is presented and it is applied to study the buckling of laminated sandwich plates. The present theory satisfies the conditions of transverse shear stress continuity at all the layer interfaces including transverse shear stress free conditions at the top and bottom surfaces of the plate. The variation of in-plane displacements through thickness direction is

M. K. Pandit; B. N. Singh; A. H. Sheikh

2008-01-01

477

Transverse and torsional complex vibration systems for ultrasonic seam welding of metal plates  

Microsoft Academic Search

Transverse and torsional complex vibration systems for ultrasonic seam welding of metal plate specimens, using a 27kHz complex vibration disk welding tip vibrating in transverse and torsional vibration modes, were studied. Using a complex vibration welding system with a welding tip vibrating in elliptical or circular locus, thick plate specimens can be welded with a more uniform and larger area

J. Tsujino; T. Ueoka; T. Kashino; F. Sugahara

2000-01-01

478

Effect of Ultrasound on the Performance of Nickel Hydrazine Electroless Plating Baths  

Microsoft Academic Search

This paper addresses the relationship between morphology of metallic skin layer and process parameters of hydrazine based electroless plating baths during the fabrication of nickel-ceramic microfiltration membranes. While process performance was evaluated in terms of overall conversion and metal plating efficiency, the film morphology was characterized in terms of average metal film thickness, pore size and percent pore densification. Sonication

Vijaya Kumar Bulasara; Ramgopal Uppaluri; Mihir Kumar Purkait

2011-01-01

479

Effect of Ultrasound on the Performance of Nickel Hydrazine Electroless Plating Baths  

Microsoft Academic Search

This article addresses the relationship between morphology of metallic skin layer and process parameters of hydrazine-based electroless plating baths during the fabrication of nickel-ceramic microfiltration membranes. While process performance was evaluated in terms of overall conversion and metal plating efficiency, the film morphology was characterized in terms of average metal film thickness, pore size, and percent pore densification. Sonication was

Vijaya Kumar Bulasara; Ramgopal Uppaluri; Mihir Kumar Purkait

2012-01-01

480

Stresses that drive the plates from below: Definitions, computational path, model optimization, and error analysis  

Microsoft Academic Search

We divide the torques on each surface plate into three parts: lithostatic pressure, side strength, and basal strength. We compute each part for each of 52 plates using a thin shell finite element model of the lithosphere with topography, variable heat flow, variable crust and lithosphere thicknesses from seismic data, transient geotherms, nonlinear rheology, and weak faults. We present an

Peter Bird; Zhen Liu; William Kurt Rucker

2008-01-01

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