一、蒸发:使含有不挥发物质的溶液沸腾汽化并移出蒸气,从而使溶液中溶质浓度提高的单元操作 称为蒸发。所采用的设备称为蒸发器。蒸发是在液、固相之间进行,化学工业中以蒸发水溶液为 主,蒸发以流体输送为基础仍遵循传热基本规律。(蒸发效果是从溶液中分离出部分溶剂一传质过 程;实质上是传热壁面一侧的蒸汽冷凝与另一侧的溶液沸腾间的传热过程一传热。物理上的蒸发: 在溶液表面发生的气化现象

2.1 scalar and vector quantities 1. scalar Physical concepts that require only one numerical quantity for their complete specification are scalar quantities. 2. vector Vector quantities require for their complete specification a positive quantity, called the magnitude of the vector and the direction otice:Not all things with a magnitude and direction are vectors

Chapter 3 Kinematics I: rectilinear motion Motion implies change, and it is change make life-and physics-visible and interesting. Kinematics is the theory about the description of motion. Physical theories are creations of the human intellect; they must be invented rather than discovered

1.熟悉同步电动机的结构; 2.熟悉工作原理,理解电枢反应的物理意义; 3.掌握电压方程、相量图、矩角特性和功角特性 4.了解同步电动机的异步起动方法

一、引起磁通量变化的原因 1、稳恒磁场中的导体运动,或者回路面积变化、取向变化等动生电动势 2、导体不动,磁场变化感生电动势

What is FBG? An in-fibre Bragg grating is constructed by varying the refractive index of the core lengthwise along the fibre. Light of the specified wavelength traveling along the fibre is reflected from the grating back in the direction from which it came. Wavelengths which are not selected are passed through with little or no attenuation

一、有界空间中的电磁波 1.无界空间中横电磁波(TEM波) TEM波:电场和磁场在垂直传播方向上振动的电磁波。平面电磁波在无界空间中传播时就是典型的TEM波

2电流和静磁场 一、电荷守恒定律 1、电流强度和电流密度(矢量) 单位时间通过空间任意曲面的电量(单位:安培)大小:单位时间垂直通过单位面积的电量方向:沿导体内一点电荷流动的方向

What needed? to combine signals and/or to split them multiple ways up to 1000X1000 for WDM LANS three important characteristics Return Loss the amount of power that is reflected and thus lost Insertion LoSs the amount of signal lost in the total transit through the device Excess Loss additional loss of a device

一.用势描述电磁场 本节使用最普遍的电磁场方程引入矢势然后讨论 电磁辐射问题(仅讨论均匀介质)