变幅

In addition, some experience formulas for them are regressed. The third chapter establishes a unified S-N curve equation to calculate multi-axial fatigue ultimate strength of concrete considering both the effect of confinement and minimum/maximum stress ratio, based on the triaxial fatigue test data in this paper and the test results under uniaxial and biaxial fatigue loading in previous literatures. Moreover, the consistency of calculating condition fatigue ultimate strength with fatigue life distribution and initial ultimate strength distribution is analyzed.

第二章简要地介绍了本文三轴疲劳试验装置，进行了两向等侧压约束下混凝土立方体试件三轴受压等幅和变幅疲劳试验，分析了三轴受压疲劳破坏机理，给出了相应的疲劳破坏试验判断标准；得到了混凝土在两向侧压约束下单级和多级受压疲劳的变形发展规律，包括最大纵向应变、残余应变、最大纵向应变率和疲劳变形模量等随循环次数的发展规律以及疲劳损伤的演变规律，并给出了相应的经验公式。

To resolve thismodel,one approximate liner first derivative equation is used.An simple caculatemodel is setted up for caculating the motive adjust,and a mathematical equation incaculating the range of pressure motion in the system.Experiment data showe thatthese models have high accurecy.

在此基础上，对分析模型采用一阶微分近似线性化处理，建立了计算动态调节过程的简化计算模型，并以此建立了计算系统压力动态变幅的计算式，试验表明简化模型具有较高的精度。

That indicated the availability of SRAP technique in studying genetic variability in Arachis. Estimates of genetic distance among the 28 accessions Arachis section ranged from 0.12 to 0.75 with average genetic distance of 0.42. A genetic distance clarified that A-genome A. duranensis was most closely associated with tetraploid germplasm, which could be A-genome donors. Dendrogram of cluster analysis classified 28 accessions Arachis section into two groups: one including tetraploid germplasm, and A.

聚类分析表明，28份花生材料间的遗传距离变幅为0.12~0.75，平均为0.42，A基因组物种Arachis duranensis与栽培种花生的亲缘关系最近，可能是栽培种花生的A基因组的供体。28份种质分为两大类，第一大类包含四倍体种质及A基因组的A。

Variable-amplitude fatigue tests for concrete in tension under single and bi- lateral pressure s are conducted.

本文进行了混凝土分别在单、双向侧压作用下受拉变幅疲劳试验，得到了疲劳寿命和残余应变。

Based on the analysis model, the ultrasonic transfer on the horn of wire bonder was studied.

摘要基于解析模型的方法，研究了超声波在热超声金丝球引线键合机变幅杆中的传递规律。

The niche breadths of same plants vary greatly among different communities and the competitive relations of the plant species in different communities vary depending on the combined actions of the niches of the species, stable landforms and soil conditions, and annual rainfall fluctuations.

同一种植物在不同群落中的生态位宽度变幅较大，不同群落内部植物种竞争关系的差异是由物种的生态位和由相对稳定的地貌、土壤条件以及随年际变动的降水条件共同作用的结果。

Then, the structure of vibration system is brought forward, the composite vibration system composed of conical horn and disc.

然后，提出了振动系统的构成，即圆锥形变幅杆与圆盘组成的复合振动系统。

On this basis, with the help of four-terminal network,the coniform horn working at 20 kHz is designed.

并在此基础上，用四端网络法设计了工作频率为20kHz的圆锥形超声变幅杆。

From the motion equation of the bar which vibrates one-dimensionally and longitudinally, the model of mechanical four-terminal network and the transfer equations are set up, and the natural frequency equation of coniform horn and the ratio of speed of vibration are derived.

从变截面杆作一维纵振动的运动方程出发，建立机械四端网络的数学模型及传输特性方程，导出了圆锥形变幅杆的频率方程和振速比。

With the change of cross section ratio of stepped transformer, the parabola regulation of resonance frequency is found.

发现随着阶梯形变幅杆粗细端截面比的改变，谐振频率具有抛物线状变化规律，呈现先下降后上升的趋势。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。