查询词典 particle accelerator

The main research work of this paper are focused on following areas:(1) Based on review of the theory and methods on measurements of particle fields, a new idea for obtaining particle size and velocity distribution within a spray through imaging the particle field with a laser light sheet was put forward;(2) A DPIV (Digital Particle Image Velocimetry) system, is fit for velocity measurements of low speed flows, was developed and expended to particle size distribution measurement;(3) An arithmetic for particle velocity field reconstruction was developed, and the velocity distribution of water mist was also obtained;(4) A software system for particle analysis, which based on image geometry emend, de-noise and image partition was developed, the parameters such as particle size distribution, mean diameter, number of particles, minimum and maximum diameter can be got with this system;(5) A water mist system was developed and its characteristics, such as droplet velocity, size distribution, number of droplets and spray cone angle under different conditions were obtained from experiments with PIVS;(6) The measurement results of water mist characteristics with PIVS were compared and analyzed with the simply simulated results, and in addition, in order to verify the accuracy of PIVS, some experiments were conducted with the standard particles, such as glass-ball with known mean diameter of 50μm and 115μm, metallic coated tracing particle with mean diameter of 12μm;(7) Some experimental studies on interaction of water mist with liquid pool fires were conducted.

本论文的主要工作包括以下几个方面：（1）在对粒子场测量的相关理论和具体方法进行综述分析的基础上，提出了通过采用激光片光对粒子场进行成像以获取其粒径和速度等参数分布的新思路；（2）研制了适宜于低速流动速度场测量的DPIV(Digital Particle Image Velocimetry)系统，并使其实现了对粒子场粒径分布的测量功能；（3）研制了基于粒子运动轨迹的速度场重建算法，获取了细水雾雾场的速度分布；（4）研制了基于几何校正、去噪、图象分割等图象处理方法的"粒度分析软件系统"，该系统既可分析给出粒子场的粒径分布直方图和平均粒径，还可给出粒子的数目以及最大、最小粒径等信息；（5）建立了一细水雾发生系统，并应用上述方法对不同压力条件下细水雾系统的雾场特性（如速度分布、雾滴粒径分布、雾滴的数目、喷雾张角以及雾化长度等）进行了实验测量研究；（6）对细水雾特性参数的PIVS测量结果与计算机简单模拟计算结果进行了定性比较分析，并利用平均粒径为50μm和115μm的玻璃球以及12μm的标准示踪粒子对PIVS系统的粒径和速度测量结果进行了实验验证，同时对其局限性进行了分析讨论；（7）对不同工况条件下细水雾与油池火相互作用的过程进行了模拟实验研究。

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。

Some technical problems arose during the debugging of the accelerator. The ion source did not produce arc. The accelerator tube cracked. The control system was out of order. The transporting capacity of the charge belt degraded. The corresponding reasons were analyzed and some measures were adopted to solve the problems. The drawing voltage was raised to its predetermined position after the ion source produced arc and should be reduced to zero before turning off the accelerator. Transition flange was lathed and the accelerator tube was re-assembled. The control equipment at high voltage was shielded. TVS diodes were installed at the input and output ends.

调试中出现了离子源不起弧、加速管破裂、控制系统失灵和输电带输电能力降低等技术问题，分析了出现这些问题的原因，然后分别采取了相应的措施加以解决：变换工作流程，在每次关机前先把引出电压降为零，开机时等离子源起弧后再把引出电压升到预定值；对过渡法兰进行车加工，重新封装；对高压端的控制设备采取屏蔽措施，在输入、输出端使用TVS二极管，对控制软件进行抗干扰设计；对绝缘气体进行循环干燥等。

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。

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。

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。

Intelligence power: the driver steps down the accelerator pedal to intelligence power switch and continue to step it down with bigger force when the vehicle needs accelerating and overpassing other vehicles, the accelerator pedal will press down the intelligence switch when the accelerator exceeds the normal full accelerated position; now the engine will emit higher power than rated power in a short time, so the vehicle will get a stronger acceleration.

智能动力：当车辆需要加速超车时，司机踩下油门踏板至智能动力开关，并继续以较大的力往下踩时，油门超越正常的全油门位置，将智能开关压下，此时发动机会短时地发出比标定功率更高的功率，车辆因而获得更加强劲的加速性。

The first hydromagnetic accelerator and second hydromagnetic accelerator can be run in accelerator mode and power generator mode according to the requirements.

第一和第二磁流体加速器可根据需要运行在加速器模式和发电机模式。

Putt your way through 36 fun-filled holes of minigolf on 3D designed courses with elevated greens, bunkers, bridges and water hazards, among other crazy obstacles.

您的推杆方式，通过36个有趣的填孔迷你的三维设计的课程，以提升绿党，掩体，桥梁和水的危害，除其他疯狂的障碍。

Some participles can be used either as attributes or as predicatives.

有些分词既可当定语用，也可当表语用。