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101.
This paper develops a closed-form solution for anti-plane mechanical and in plane electric and magnetic fields in a magnetoelectroelastic
layer of finite thickness. Explicit expressions for the stresses, electric fields, and magnetic fields, together with their
intensity factors are obtained for the extreme cases for impermeable and permeable cracks. Solutions for some special cases,
such as a magnetoelectroelastic layer with infinite thickness, are also obtained. Applicability of the crack face electromagnetic
boundary conditions is discussed. It is found that the crack profile is important in obtaining the correct electromagnetic
fields and their intensity factors. The stress intensity factor, however, does not depend on the crack face electromagnetic
boundary condition assumptions. 相似文献
102.
A meshless method based on the local Petrov-Galerkin approach is proposed for the solution of quasi-static and transient dynamic
problems in two-dimensional (2-D) nonhomogeneous linear viscoelastic media. A unit step function is used as the test functions
in the local weak form. It is leading to local boundary integral equations (LBIEs) involving only a domain-integral in the
case of transient dynamic problems. The correspondence principle is applied to such nonhomogeneous linear viscoelastic solids
where relaxation moduli are separable in space and time variables. Then, the LBIEs are formulated for the Laplace-transformed
viscoelastic problem. The analyzed domain is covered by small subdomains with a simple geometry such as circles in 2-D problems.
The moving least squares (MLS) method is used for approximation of physical quantities in LBIEs. 相似文献
103.
William McBride 《Particulate Science and Technology》2006,24(1):59-70
The ability of a granular bulk material to transmit internal shear stress is a fundamental property that is often overlooked or underestimated, yet it is this ability that allows many observed physical phenomena to occur. One such area that continues to be a focus for numerical, theoreticals and experimental researchers is the pressure that a stockpile of granular material places on the supporting surface. While appearing to be a simple problem, the ability of granular materials to transmit shear stress makes this an extremely complex problem. This article presents high-quality data collected under a 2 m high stockpile and full details of the experimental facilities used in the collection of the data.
The work presented is of significant value, having a much greater scale than previous studies (Jotaki & Moriyama, 1979; Lee & Herington, 1971; Smid & Novosad, 1981), and the deliberate inclusion of a central reclaim channel offers insight into stress changes during gravity reclaim and refilling. The results of this work have shown that the so-called 'M' pressure does exist under larger stockpiles both with and without reclaim hoppers; of more significance is the reemergence of the M pressure upon refilling of an emptied stockpile. This clearly illustrates that the M pressure is a robust and natural pressure distribution for a conical stockpile. 相似文献
The work presented is of significant value, having a much greater scale than previous studies (Jotaki & Moriyama, 1979; Lee & Herington, 1971; Smid & Novosad, 1981), and the deliberate inclusion of a central reclaim channel offers insight into stress changes during gravity reclaim and refilling. The results of this work have shown that the so-called 'M' pressure does exist under larger stockpiles both with and without reclaim hoppers; of more significance is the reemergence of the M pressure upon refilling of an emptied stockpile. This clearly illustrates that the M pressure is a robust and natural pressure distribution for a conical stockpile. 相似文献
104.
105.
106.
107.
Seogil Oh Jungwoo Moon Taewook Kang Surin Hong Jongheop Yi 《Journal of Electroceramics》2006,17(2-4):999-1003
The use of surface plasmon resonance (SPR) spectroscopy has been applied to a wide variety of fields such as biosensors and
surface analysis instruments. In general, a SPR substrate is prepared using self-assembled monolayer (SAM) method of organic
molecules as receptor for the target on a layer of gold or silver. However, mesoporous inorganic materials such as SBA-15
have benefits as sensor substrate for SPR. Mesoporous silica has a large surface area which receptor molecule can be attached
and has a rigid body which has an excellent stability in the extreme condition compared to organic sensing layer. We prepared
an organic modified mesoporous silica and successfully immobilized it on a gold surface, in an attempt to use as a substrate
for SPR spectroscopy. For the comparison of sensitivity of prepared substrate, Pt2+ detection was selected as a model system. Substrate prepared in this study exhibited the capability of selective sensing
for Pt2+ ions. 相似文献
108.
基于PLC的配料计量装置的设计 总被引:1,自引:0,他引:1
冶金生产中,各种原料之间的配比精度对生产过程的稳定和产品的质量有重要的影响。目前使用的配料系统计量精度低,瞬时物料流量波动大,系统复杂。本文介绍的计量装置的计量过程是对料斗内物料的减少量进行计量,以减重秤为主,配料精度达到0.5%级。 相似文献
109.
110.
石墨炉原子吸收测定化探样品中痕量金的研究 总被引:6,自引:1,他引:6
采用以王水分解样品,泡沫塑料富集,硫脲解脱,石墨炉原子吸收分光光度计测定微量金。研究了测定时干燥温度和时间的选择,原子化温度和时间的选择,灰化温度和时间的选择,以及王水体积分数对吸附效果等条件对测定结果的影响。该方法检出限为0.2×10-9,经国家一级分析标准样品验证,结果与标准值相符。 相似文献