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Expanding the unknown function in a small perturbation parameter and using a successive expansion in a Taylor series for the water particle path and the period of a particle motion, the third order asymptotic expressions for the Lagrangian particle trajectories and the period of particle motion can be derived directly in Lagrangian form.

藉由一系列连续的Taylor级数展开，於考量波动场中各流体质点之运动轨迹与运动周期下，将已知的Eulerian解转换成完全未知的Lagrangian形式解。

The study shows that in the radial direction the dynamic forces acting on the particle balance on the particle itself; there is not a so-called trajectory of the particle in which the composition of forces acting on the particles is zero, but there is a trajectory of the particle in which the radial slip velocity of particle is zero, the tra...

通过对固体颗粒的运动和受力分析发现固体颗粒在沉降过程中径向合力几乎处处为零，不存在所谓的径向合力为零的一个平衡轨迹面，但存在着一个径向沉降速度为零的轨迹面，这一轨迹面就是平衡轨迹面法所要寻找的；首次推导出了该轨迹面半径与固体颗粒直径、水力旋流器自身几何参数以及操作参数之间的定量表达式。

The kinematics parameters were firstly presented by establishing the mechanical model of relation between the vibration screen and particle to deduce periodicity condition of particle motion,then disturbing function of particle motion for periodic motion was educed by using Poincaré mapping method,and studied motion characteristics of particle in vibration screening in terms of numerical analysis.

利用振动筛与颗粒之间关系的运动学模型，导出颗粒运动的周期性条件；然后利用Poincaré映射方法，推导出颗粒的运动对周期运动的扰动方程；最后对振动筛分过程中颗粒运动特性进行了数值计算研究，得出了筛面上颗粒运动是经周期分叉和概周期分叉通向混沌的演化过程。

Based on the model of DLA, this paper simulates the process of aggregation's growth for random walk particles from local area on two-dimension Euclidean plane. The aggregation is confined to Euclidean circular plane for large enough particle walking area and far enough partial source distance. The centre of the Euclidean circular plane is on the line between the particle source's symmetric centre and the seed particle, and is more closer to the particle source than the seed particle. Though the rate of aggregation growth is different in different directions, the whole aggregation shows fractal structure.

以DLA模型为基础，模拟研究了在二维欧几里德平面上由局部区域内产生随机运动粒子的聚集生长过程，发现对于足够大的粒子运动区域和足够远的粒子源距离，凝聚集团大体上被限制在欧氏圆形面内，圆心在粒子源对称中心和种粒子的连线上，且比种粒子更加接近粒子源；凝聚集团朝各个方向的平均生长速率虽然不同，但整体仍呈分形结构。

This project studies the scale-dependent deformation behavior of the metal matrix composite, the void nucleation and void growth mechanisms at the micron/submicron scale. The main results are:(1) In prophase, growth and coalescence of the void embedded in the graded matrix are analyzed in detailed;(2) Based on the infinite solid model containing a micro-void, coupling effects of the void shape and the void size on the void growth are studied carefully, the results show that it seems to exist a critical equivalent void radius, which is associated with the material length. When radius of a microvoid is close to or smaller than the critical void radius, the micro-void growth rate is essentially eliminated;(3) The coupling effects of the particle shape and size on the mesoscopic stress fields within the particle and matrix are also investigated by introducing the conception of inclusion/matrix interfacial energy. The results show that the stress concentration factors within the particle and on the matrix/particle interface are also strongly size-dependent,so the void nucleation mechanism is size-dependent.(4) By employing a specific orthogonal curve coordinate frame and a 'kernel function' conception, a 'unified method'solving the spheriodal and spherical void problems is suggested; by this unified method, size-dependent plastic potentials of the porous materials containing the spheriodal or spherical voids are obtained, which extend the traditional Gurson model for the spherical void and GLD model for the spheriodal voids to the micron scale.(5) Based on the RVE model containing the spheriodal or spherical particles, the influences of the particle shape and size on the size-dependent mechanical behavior of metal matrix composite are studied.

中文摘要：本项目对金属基复合材料在微细观尺度下的尺度相关变形行为、孔洞形核及长大的机理和模型进行了研究，取得了如下主要结果：1）在前期研究中，探讨了基体的梯度分布对孔洞长大和聚合的影响；2）基于含孔洞的无限大体模型，探讨了孔洞形状和孔洞尺寸对其长大的耦合作用，结果表明：可能存在一个与材料特征长度相关的临界孔洞尺寸，当椭球孔洞的等效半径小于临界孔洞半径时，孔洞的长大受到明显抑制；3）通过引入基体/夹杂界面能的概念，分析了夹杂尺寸、夹杂形状对材料细观应力场的耦合影响，结果表明：颗粒内部和界面上的应力集中因子强烈地依赖于夹杂的尺寸和形状，因此，孔洞的形核机理是尺寸相关的；4）采用一种特殊的正交曲线坐标系和引入"核函数"的概念，"统一"地得到了含椭球和球形孔洞的材料的尺寸相关塑性势，它将传统的Gurson球形孔洞模型和GLD椭球孔洞模型推广到微尺度范围；5）基于含椭球和球形夹杂的体胞模型，初步研究了夹杂形状、夹杂尺寸对金属基复合材料尺寸相关力学行为的影响。

That shows time has a close relationship with matters which contain life. Learned from biology, we know the differences to distinguish living being and the rest is: the matter micro particle contained living being has the capability to regenerate; in other words, the special species matter micro particle of living being can regenerate 2 or 3 even more micro particle containing life. On the contrary, although the non living being micro particle changes continuously, the micro particle can not regenerate 2 or 3 even more counterparts.

这就说明了时间同含有生命现象的物质有着密切的关系，而生物和非生物区别又在何处；我们从生物学中知道：它们的区别是：含有生命现象的物质微粒能够有再生的变化能力，也就是说一个以本种形式存在的含有生命现象的物质微粒能够变成两个、三个以至更多个同样的含有生命现象的物质微粒，而非生物的物质微粒虽然是在不停的发生变化，非生物的物质微粒却不能变成两个、三个以至更多个不含有生命现象的物质微粒的。

A novel ultrastable particle-stabilized foam slurry was prepared by alumina particles modified by the short amphiphiles to make them partially lyophobic and to initiate direct foaming with vigorous stirring.

采用短链两亲分子戊酸修饰氧化铝颗粒，使其部分具有的疏水性，在机械搅拌的作用下，形成了粒子稳定型泡沫(particle-stabilized foam)，制备了一种新型的超稳定陶瓷泡沫浆料。

The mainly conclusions in our research are as flowing: tungsten trioxide powders with 100 nm primary particle are obtained by spray drying,calcination and wet milling process, and an average size of quadric particle composed of agglomerated particles is 0.64 μm; tungtsen powders with 39 nm grain size and 60 -100 nm primary particle are produced directly from previous tungsten trioxide using one step reduction in hydrogen at 700℃, and an average size of quadric particle of tungsten powder is 2.91 μm; tungsten trioxide and copper tungstate compound powders with 100 nm - 200 nm primary particle are produced using ammonia metatungsten and copper nitrate as raw materials by spray drying,calcination and wet milling process;the compound powders are transformed completely into tungsten and copper compound powders by reduction in hydrogen at 700℃,in which tungsten grain size is 59 nm and copper grain size is 51 nm; primary particle size of compound powders is 80 - 120 nm,and an average size of agglomerated quadric particle is 1.86 μm; tungsten nitride powders with 35 nm grain size are prepared from tungsten trioxide powders by nitrogen treatment thoroughly in pure ammonia at 650℃, and an average size of agglomerated quadric particle is 0.64 μm in normal temperature.

研究结果表明：采用喷雾干燥—焙烧—球磨工艺可以制备出粒度约为100nm的WO_3粉体，它们在团聚后形成的二次颗粒平均粒度为0.64μm；采用一步直接氢还原方法可在700℃下从上述WO_3粉体制备出晶粒尺寸为39nm的、一次颗粒粒度为60-100nm的W粉体，其二次颗粒的平均粒度为2.91μm；以偏钨酸铵、硝酸铜为原料，采用喷雾干燥—焙烧—球磨工艺可制备出一次粒度为100-200nm的WO_3和CuWO_4混合粉体；采用氢还原工艺可在700℃下将这种粉体完全转变为W、Cu复合粉体，其中W的平均晶粒粒尺寸为59nm，Cu的平均晶粒尺寸为51nm；复合粉体的一次颗粒尺寸为80-120nm，在常温下团聚后形成的二次平均粒度为1.86μm；采用纯氨氮化工艺可以在650℃下由WO_3粉体制得WN，其晶粒尺度为35nm，在常温下团聚后的二次平均粒度为6.4μm。

When switching on the machine, the material is conveyed into the grading unit by the feeding devices. The material is separated into fine particle and coarse particle here, the qualified fine particle is released directly from the air pipe; the coarse particle enters the grinding chamber, grinded under high speed strike of the hitting block and then is transferred by the air pipe to the worm grading device. The satisfied particle is released with the exhaust air from the exhaust pipe and is collected as final product.

粉碎时，待粉碎物料由送料装置均匀送到分级室，在这里进行预先分级，原料中的合格颗粒经分级后从排气管排出，粗颗粒进入粉碎室，在冲击锤块的高速冲击和研磨作用下被粉碎，粉碎后的物料经进气管进入的上升气流作用下输送到蜗轮分级机进行先分级，合格颗粒经分级后从排气管随尾气一起排出后收集为产品，粗颗粒再次返回粉碎室继续粉碎。

Flow characteristics of flow field in the header of platefin heat exchanger were investigated by means of particle image velocimetry and a series of velocity vector and streamline graphs of different crosssections before and after the header improvement were achieved.

利用Particle Image Velocimetry粒子图像测速仪对板翅式换热器入口结构改进前后的流场进行了实验测试，获得了入口结构内部不同剖面处的流场速度矢量和流线分布图。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。