一定尺寸的

This indicates that all the solids and liquids with a certain size can be acoustically levitated on the earth in principle.

这不仅证实了本文所提出的单轴式声悬浮优化设计理论，同时还表明，声悬浮原则上可以在地面条件下悬浮起一定尺寸的任何固体和液体。

The problem of the error accumulation ,three different kinds of linear size marking form is analysed here.

分析了尺寸公差法标注尺寸的三种形式，它们都存在不同程度的误差积累，在一定条件下采用位置度注法，可以解决尺寸标注中的误差积累问

Classical Top-Hat transform only uses structure element in one size and can not effectively extract objects in the image, because only part of objects may have a high response for a given structure element size and a lower response for the rest.

经典的Top-Hat变换用唯一尺寸的结构元素对图像进行处理，并不能有效地提取目标，图像上面的结构或目标不一定对那个尺寸的结构元素敏感。

A twist drill is designed to drill a hole which has a particular size.

麻花钻用来钻削具有一定尺寸的孔。

Similarly, if the strong shear, which could suppress all the scattering in the quiescent two phase region, stopped, the follow-up phase separation also displayed characteristics of anisotropism and relaxation, In this dissertation, the transposed"butterfly'and"streakpattern were observed for the first time within the shear-history-influenced phase separation, which is found closely relevant to the anisotropical relaxation behavior of macromolecules. 5. The phase separation kinetics of PS/PVME under oscillatory shear was further studied on the base of that done under simple shear. It is found that, under specific temperature and strain amplitude, the occurrence of phase separation is strongly contingent on oscillatory frequency and only intermediate frequency could effectively induce phase separation; If all considered oscillatory shear could stimulate phase separation, a fixed frequency can maintain specific most probable phase size and higher frequency yields smaller phase, which makes a higher elasticity but weaker stress relaxation; Furthermore, higher frequency can produces stronger compulsory oscillation on the MPPS but won't change the mean of the MPPS. Under given frequency and strain amplitude, the phase separation kinetics dramatically depends on the phase angle of oscillation and the phase separation corresponding to different phase angle follows different dynamical process.

在简单剪切场下相分离动力学研究的基础上进一步对振动剪切场下PS／PVME的相分离动力力学进行了尝试性的研究，发现：在一定温度和振幅条件下，相分离的发生强烈的依赖于振动频率，只有中等频率的振动剪切才能有效地促进相分离的发生；在都能使相分离发生的前提下，一定频率的剪切能够使体系维持一定的最可几相尺寸，较高频率的剪切导致体系形成的相区尺寸较小，因而体系的弹性效应较强而应力松弛效应较弱；同时，更高频率的剪切对最可几相尺寸的强迫振动效应越强，但不会使最可几相尺寸的平均值发生改变；在一定的振幅和频率条件下，相分离的动力学过程会强烈地依赖于相位角，不同相位角对应的相分离遵循不同的动力学过程但机理一样。

Changes in Xc for different pulp cellulose fibers are not the same during the ultrasonic treatment. Crystallization and decrystallization may both exist during the treatment at the conditions of lower-intensity ultrasonic wave. After treatment with ultrasonic Xc of MBKP cellulose is decreased and that of EBKP is increased. The changes of Xc of different pulp cellulose are more closely correlated to the fibers' morphology size and the cavitation state. The maximum Xc of 84% is obtained when BEKP cellulose is treated under the conditions of ultrasonic frequency f=23-25kHz, power=400w, and treatment time t=720s.

不同原料来源的纤维素纤维，由于形态尺寸和超分子结构的差异，经超声波处理后超分子结构表现出不同的变化规律；超声波处理过程中，结晶和消晶两种作用同时存在；超声波功率对纤维素的结晶度有较大的影响，对晶体尺寸有一定程度的影响，但结晶度Xc与超声功率没有线性关系；在频率为23-25kHz，功率为400W条件下，对桉木漂白浆纤维进行超声波处理，可获得高结晶度（84%）的纤维素样品。

And the possibility of using this mothod to measure the grain size on line was discussed.

实验结果表明，这种方法操作简单，能够准确测量在一定尺寸范围内的板材的晶粒尺寸，并与背散射电子衍射结果进行了比较，探索了用X射线面探测器衍射系统在工业上进行金属板材晶粒尺寸在线检测的可行性。

The intensity of the ultrasonic wave will increase when the ultrasonic wave is focused by the sound lens in rock stratum.

然而 ，这种方法要受到两个因素的制约：一是增大超声换能器的功率，必然要增大超声换能器的尺寸，这在本身尺寸就很小的油井中是有一定限度的；二是当超声换能器辐射出的超声波的强度过大时，在超声换能器的周围要发生强烈的空化现象，产生大量的气泡，这些气泡将对超声波产生强烈的散射作用，导致超声波的衰减，反而降低超声波在岩层中的传播距离[1] 。

GHz ridge－loaded helical groove slow wave structure with a 20kV electron beam are given and the investigations of the effect of the ridge dimensions and electron beam parameters on the small signal gain are carried out. It is indicated from the calculation results that this type of structure is suitable for use as s SWS of high power, high gain but narrow passband millimeter TWT, of which the 3dB gain bandwidth is 3.4%. In order to increase the bandwidth, the reduction of the ridge gap or the increase of the electron beam current in an allowable range may be useful.

GHz的脊棱加载慢波结构的具体尺寸，并对此结构中小信号增益随脊尺寸的变化情况及电子注参数对其影响进行了研究，计算结果表明：此结构适宜于作为高增益窄带毫米波大功率行波管的慢波线，其3dB增益带宽为3.4%，为了展宽其工作带宽，可以适当减小间隙宽度，也可在一定范围内提高电子注电流。

Wheat straw, thermosetting resin, alcohol ,etc, were selected as raw materials and Zncl2, K2CO3,(NH4)2HPO4 and Na2B4O7·10H2O as additives. All these components were mixed uniformly according to the proportion and hot-pressed to sample with the dimension. The samples were put into the vacuum furnace and sintered in the atmosphere of nitrogen ,and the termination temperature was 300℃, 400℃, 500℃, 600℃, 700℃ and 800℃, respectively, and woodceramics were prepared and the effects of the additive on the ratio of remaining carbon were investigated.

试验选取了麦秸、热固型酚醛树脂、酒精等为原料，氯化锌、碳酸钾、磷酸氢二氨以及硼砂等为阻燃剂，按照一定的比例混合均匀并热压成一定尺寸的坯体，再将坯体在氮气保护下按两种升温模式分别烧结至300℃、400℃、500℃、600℃、700℃和800℃，制备出各温度点下的木质陶瓷，观察分析了阻燃剂对其残碳率的影响。

The basic concept of FOP can be summarized as to further optimize effective prescription according to the standard of curative effects and with the aid of modern science and technology and theories of traditional Chinese medicine.

其基本内涵可概括为：以确有疗效的中药复方为研究对象，以现代科学技术和传统中医药理论为技术支持，以该复方所治病证的药效响应为评价标准，以优化重组疗效更优的新复方为研究目的。

Ever since our world has been a world, native forests have been indiscriminately exploited by man.

自从我们的世界一直是世界原生森林被任意剥削人。