叠层结构

The dissertation focuses on the phenomenon of wave propagation of piezoelectric periodical composite laminated plate. By using the motion equations and Gauss theorem cooperative with constitutive relations of piezoelectricity, the governing equations can be determined.

本文主要是要探讨压电周期叠层板波传现象，所以由本构方程式配合运动方程式和高斯定理以获得统御方程式，此等方程式在周期结构内具有平移对称关系，所以位移场和电位场的形式可以布拉克理论表示，进而得到代表周期结构行为的统御方程式。

That's where lamination comes in.

这是引进叠层结构的原因。

Structure characteristics of laminated composites in nature such as nacre are described briefly in this paper.

以贝壳珍珠层为例，简要介绍了天然叠层状生物材料的结构特征，并针对叠层状仿生材料的设计原理、制备技术及其研究现状等方面加以综述。

Based on the variational principle of virtual voltage and virtual displacement derived in this thesis and the classical theory of linear laminated plates, and by using the constitutive equations of elastic piezoelectric materials, and the DKQ quadrilateral plate bending element, the finite element modeling for the fabric reinforced laminated plates with nonlinear voltage-electric strain relationship of piezoelectric actuators has been established for the first time in this thesis. And the expressions for the electric loadings with obvious mechanical meaning and convenient for computation are established, which can be used to the deformation analysis of laminated plates with piezoelectric actuators under specified voltages.

以本文直接导出的压电结构的虚电势—虚位移变分原理为基础，依据经典线性层合板理论和压电弹性体的本构方程，采用基于离散法线假设的DKQ四结点任意四边形薄板弯曲单元，首次建立了考虑非线性电压—电应变关系的含压电致动器的纤维增强型层合板的有限元分析模型，并推导建立了力学意义明确、便于计算的电荷载表达式，可用于指定电压条件下纤维增强型叠层合成板的变形分析。

The substitution of oxygen for carbon dioxide in the atmosphere, which occurred in the Proterozoic, caused probably by cyanobacteria in the form of stromatolites, caused changes leading to the evolution of aerobic organisms.

发生在原生代的大气中氧气取代二氧化碳，可能是由藻青菌在叠层结构上造成的；大气改变引发的变化，导致了好氧生物的发展进化。

The size of the diplexer was 18.3mm×15.6mm×0.5mm, at the frequency of 1.87GHz and 2.34GHz, the decay was higher than 55dB, so it suppressed the local oscillator signal and its mage reconstructor tube signal effectively, which met the design of filter with miniaturization. And then the three-dimensional laminated structures were used to realize the design of miniaturization, which was good for the later research.

该双工器尺寸为18.3mm×15.6mm×0.5mm，在频率1.87GHz和2.34GHz处衰减大于55dB，有效的抑制了阻带上的本振信号及其镜像信号，达到了设计指标，并利用三维叠层结构实现了小型化的目的，为以后的工程设计提供了有益的探索。

More stories are added to a multi-storey RC frame using lead laminated rubber bearings. A program is developed with MATLAB language to conduct elastic-plastic time history analysis, according to the optimization results of lateral rigidness and damping ratio of isolation layer based on energy criterion, and two real ground motion records and a synthetic record are input.

结合一幢多层框架结构应用铅芯叠层橡胶支座进行加层改造的工程实例，在对隔震层的抗侧刚度和阻尼比基于能量准则进行优化的基础上，利用Matlab语言编制了弹塑性时程分析程序，输入两条实际地震动记录和一条人工波。

Each lamination defines an axis collinear with an axis of each other lamination in the stacked formation.

每片叠层片确定了一根轴线，此轴线与在叠放结构中的每个叠层片的轴线共线。

The analysis on unilateral, bilateral and lateral-torsional coupled seismic response of base-isolated structures with lead rubber bearings is carried out. The maximal displacement of the bearings is studied. The influence on lateral-torsional coupled seismic response of base-isolated structures due to the excentricity and uncoupled period ratio of the superstructure, and the excentricity of the isolation system is investigated.

对铅芯叠层橡胶支座基础隔震结构进行了单向及双向地震反应对比分析，并研究了支座最大位移的确定；对结构进行了平—扭耦联地震反应分析，研究上部结构的偏心距及非耦联周期比、隔震层偏心距等因素对结构的平—扭耦联地震反应的影响，并对结构平—扭耦联地震反应的控制进行了探讨。

After introducing the basic principle and main appiica tions ofLaminated Object Manufacturing, the technical process of printer was describe in detail. Taking aim at the functional requirements and assembling relationships of the printer, the importance of LOM method in assembly check, design evaluation and construct improvement is given.

介绍叠层实体制造技术快速成型方法的基本原理和主要应用领域，并以上盖零件为例叙述热敏打印机原型的制作工艺过程，指出叠层实体制造技术在从结构设计评估、零部件间的装配检验到产品定型及样品生产的快速设计与制造模式中的作用。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。