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- The contribution fractions of electrons emitted by close collision to the total backward emission yield are 0.5, 0.55 and 0.42 for C, Cu and Al, respectively. 由于He+离子的电荷态是变化的，所以还研究了近程碰撞对总的背向电子发射产额的贡献比例，对C、Cu和Al其值分别是0.;5、0
- He lined out for home without a backward glance. 他头也不回，急忙往家里走去。
- The emission of visible light by a hot object. 白热光物体遇热发出可见光
- This part of the country is still backward. 这个国家的这个地区仍很落后。
- In some cities housing conditions went backward. 某些城市的住房条件越来越差。
- The teacher was patient with backward children. 那位老师对迟钝的学童十分耐心。
- He looked backward over his shoulder. 他回头向后看。
- The amount or rate of emission or ejection. 排放量流量、流速，或排出量，排出的速度
- She looked backward over her shoulder. 她回头往後看。
- backward emission 反向发射, 后向散射
- Sheila is very clever but rather backward in expressing her ideas. 希拉很聪明，然而在表达思想时却有些腼腆。
- Although he is clever, he is backward in giving his views. 他虽然很聪明，却不善发表他的意见。
- Frank was so backward that he hesitated to ask her to dance. 法兰克非常腼腆,不好意思请她跳舞。
- He had a firsthand taste of life in backward mountainous areas. 他直接体验过落後山区的生活。
- Emission and propagation of energy in the form of rays or waves. 发射以光线或波的形式发出和传播能量
- One set of provisions tightens emission standards. 一套使排放标准更加严格的规定。
- A backward flow of water, as from the action of oars. 反流，逆流向后流的水，如由浆的划动引起
- The backward man lacks black background. 落后的男子缺少黑色背景。
- A brief, sudden emission of air, vapor, or smoke. 一阵烟空气、蒸汽或烟雾短促而突然的散发
- An example is the emission of light from matter. 物质的发光即为一例。
