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- net density filter 纯光强过滤镜
- This paper analyses the relation between highway net density, population density and per capital GNP, and sets up a statistic model response the macro demand of national region highway-net. 分析了国家区域公路网密度与人口密度、人均GNP的关系，建立了国家区域公路网的宏观需求模型；
- net density of residential structures 居住建筑净密度
- Linear gradient neutral density filter 线性变密度中性滤光片
- Combined with density filtering technique to improve the smoothness of density field, the mesh-dependence phenomenon is overcome. 采用密度过滤技术进一步提高密度场的连续性和光滑性，从而消除了网格依赖性现象。
- Unsafe filters include color film, some non-silver black and white film, medical x-ray films with images on them, smoked glass, photographic neutral density filters and polarizing filters. 任何彩色负片、不含银的黑白负片、被烟熏黑的或用墨汁涂黑玻璃片、太阳眼镜、拍摄用中性减光滤镜、偏振镜、磁盘、光盘等，都是不安全的，肉眼看不见的光线（比如红外线）可能大量穿透这些物品，长时间观看会对眼睛造成很大伤害，因此请不要使用这些替代品进行观日。专业的日食观测镜请到专业可信赖的机构购买。
- He hit the tennis ball over the net. 他把网球打过了网。
- The ball glanced off the goal post into the net. 球撞到球门柱上斜飞入网。
- The net weight of this jar of coffee is 180 grams. 这瓶咖啡净重180克。
- If I lose my job, I've got no safety net. 我丢掉这份工作就无计可施了。
- The fish tangled in the mesh of the net has died. 那条卡在网眼上的鱼已经死了。
- Practise throwing the ball into the net. 练习投篮。
- She just tipped the ball over the net. 她刚好把球击过网。
- My fishing-line got fouled (up) in an old net. 我的钓丝跟旧鱼网缠在一起了。
- The density of population in this city is very high. 这个城市的人口密度非常高。
- The fishermen were hauling in the net. 渔夫们正在把网拉进珑。
- FFU have primary and hepa two pole filter net. FFU设有初、高效两极过滤网。
- His lawless hair was caught in a net. 他的一头乱发被网钩住了。
- The fish were caught in the meshes of the net. 鱼被网线钩住了。
- They dropped their net to the floor of the ocean. 他们把网下到海底。
