直热式阴极

In electronics, a vacuum tube or thermionic valve or just valve, is a device generally used to amplify, switch or otherwise modify, a signal by controlling the movement of electrons in an evacuated space.

真空管是一种电子设备，由抽真空的容器组成，它具有发射电子的阴极（旁热式是由灯丝加热，直热式则灯丝就是阴极）和工作时通常加上高压的阳极。阴极和阳极之间，自阴极算起，第一个电极称为栅极，再增加一个电极则称为帘栅极。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。