Micropropagation is used for the mass clonal propagation of elite lines or disease-free planting material.
微繁殖被用于优良品系或无病害种植材料的大规模无性繁殖。
Aristotle (384-322 BC) recognized the need for a conducting medium and stated that the means of propagation depended on the properties of the material.
亚里士多德(384BC- 322bc)认识到传播媒介的重要性，并指出声传播的方式取决于材料的特性。
The model of wave propagation in functionally graded material (FGM) is introduced to soil medium, and the concept of functionally graded soil medium is brought forward.
研究了将功能梯度材料中应力波传播的计算模型应用到土介质中，提出了梯度土介质的概念。
Fracture mechanism, initiation and propagation of cracks, and the control method of cracks in rock like brittle material under dynamic load are described in this paper.
本文主要论述了动荷载作用下岩石等脆性材料的断裂破坏机理、裂纹形成与扩展以及裂纹的止裂与控制等内容。
The propagation characteristics of vibrational energy flow in circular cylindrical shell with finite region of material discontinuity are investigated by wave motion approach.
运用结构振动的波动方法对有限长的材料不连续区域在圆柱壳中的能量流传播特性进行了研究。
Therefore the study of interaction of stress waves with cracks will greatly contribute to the interpretation of blasting mechanism, the stress wave propagation and the dynamic behaviour of material.
因此，研究应力波与裂隙的相互作用，对于研究岩石爆破机理、应力波传播规律以及波的反演——材料的动态特性等有着十分重要的意义。
The results showed that for the same material and the same iodine concentration, the rate of crack propagation increased with increasing temperature.
结果表明：对于同种材料在相同的碘浓度下，随着温度的升高，裂纹的扩展速率加快。
Based on status in quo of the interface crack propagation of the isotropic bi - material, the exiting problems and the tendency of the research are proposed.
在对各向同性双材料界面裂纹扩展研究现状进行综述的基础上，提出了目前研究存在的问题以及今后的研究趋势。
The study were carried out to improve the detonation propagation reliability of nonel tube by means of composition of the mixed powdered explosive designed and tube material designed.
通过采用混合药粉配方设计和导爆管管材设计等技术手段开展了提高导爆管传爆可靠性的研究。
In addition, the crack propagation and fatigue damage of CSP under wind load in the case of the material which have initial crack have been analyzed using fracture mechanics method.
此外，还运用断裂力学方法分析了材料有初始裂纹的管道在风荷载作用下的裂纹扩展及疲劳损伤。
The energy release rate for crack propagation depends only on the stress intensity factor and the material constants.
电导通裂纹模型中的静电场对裂纹尖端扩展的能量释放率不作贡献。
The study work is focused on the effect of temperature upon mechanical properties, creep, initiation and propagation of fatigue crack for the valve material.
着重温度对气门材料的力学性能、蠕变和疲劳裂纹形成与扩张的影响等问题进行分析和研究。
It is a brittle material and heterogeneous discontinuous body. The process of its failure is one of initiation of inner cracks of the rock followed by their propagation, connection and link up.
它是一种非均质不连续体的脆性材料，其破坏过程是在水力或机械作用下，岩石内部裂纹的产生、扩展、合并和贯通的过程。
The main course of fatigue fracture is due to existence of the inclusion in the material. The inclusion induce crack initiation, the crack propagation and the axe fracture in the circle stress.
疲劳断裂的主要原因是在材料中存在的夹杂物诱发裂纹源，在循环应力的作用下裂纹扩展导致断裂。
These lasers have potential applications in laser cooling, directional energy transmission, material processing, and atmospheric propagation and so on.
这类激光在激光冷却、定向能量传输、材料处理和大气传输等方面有广泛的应用前景。
The study took the L. regale seedling progeny for material, which aims at providing fundamental references for rational utilization in landscaping and seedling propagation of L. regale Wilson.
本研究以岷江百合实生后代为材料，旨在为岷江百合实生繁殖、实生后代在园林中的应用以及百合育种工作提供理论基础。
As brittle material, the cutting process is complexity, it is in general discontinuous and it is caused by the growth and propagation of the microcracks in Indus trial ceramics.
作为典型的高硬度脆性材料，其切削复杂，切削过程是一个不连续的过程，而内部微裂纹扩展是导致断裂和产生切屑原因。
In vitro propagation of garlic was studied by using regular varieties as material and B5 as the basal medium.
以常规大蒜栽培品种为试材，B5为基本培养基，研究了利用脱毒大蒜萌生幼苗的离体繁殖技术。
From the view point of material selection, we analyzed their dynamic fracture toughness and crack propagation resistance.
从选材角度对比分析了几种铝合金的动态断裂韧性及裂纹扩展阻力。
Concrete is not a ideal elastic material, and laws of wave propagation are not same with different wavelength.
混凝土并非理想弹性体，不同测试方法中波的传播规律是不同的。
And then a concept of critical intrinsic zone of crack propagation is introduced, crack propagation happens when the tress or strain status of the zone reaches to the material critical rupture value.
认为裂纹顶端存在一个决定裂纹扩展本征区，裂纹扩展是因为本征区的应力应变状态或损伤状态达到材料的断裂韧性才发生的。
Q-P process significantly improve crack initiation and propagation resistance of 300M steel, and extend the uniform plastic deformation stage of the material, and finally put off the necking creation.
Q-P工艺明显提高了300M钢抗裂纹形成和扩展的能力，延长了材料的均匀塑形变形阶段，推迟缩颈发生。
The major phenomena that affect propagation through fiber are material absorption, dispersion, and nonlinear x(3) effects associated with fused-silica.
熔石英中的材料吸收、色散和三阶非线性效应是光纤中影响光传输的主要因素。
The major phenomena that affect propagation through fiber are material absorption, dispersion, and nonlinear x(3) effects associated with fused-silica.
熔石英中的材料吸收、色散和三阶非线性效应是光纤中影响光传输的主要因素。
应用推荐