Outgassing of internal materials is one of the main factors that cause vacuum deterioration of low-light-level image intensifiers and shorten their lifetime (especially storage lifetime). To perceive the attenuation mechanism of the vacuum degree of image intensifiers from the microscopic view, the outgassing characteristics of lead silicate glass used for the fabrication of microchannel plates (MCPs), which are the core components of image intensifiers, were numerically simulated by giant canonical Monte Carlo and molecular dynamics methods. A glass structure model of the third-generation MCPs was constructed, and the diffusion coefficients and molecular motion trajectories of hydrogen, carbon dioxide, carbon monoxide, water vapor, oxygen, and methane gases, together with their outgassing rates and cumulative outgassing amounts, were calculated based on the condensed-phase optimized molecular potentials for atomistic simulation studies force field. The calculation results show that the rising temperature of MCP glass augments the diffusion coefficients of these gases, which makes the outgassing rates increase in the initial stage but then decrease relatively quickly. Among these six kinds of gas molecules, hydrogen molecules have the largest skip distance and the highest diffusion coefficient because MCP glass can supply more effective diffusion paths for the gas molecules with a relatively small size. When an MCP glass lies in vacuum, first, the cumulative outgassing amounts of various gases from it increase rapidly and then gradually reach stable values, and the cumulative outgassing amount of hydrogen tends to reach a stable value faster than that of other gases due to its highest diffusion coefficient.

中文翻译：

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微通道平板玻璃除气特性数值模拟

内部材料放气是造成低照度图像增强器真空劣化并缩短其使用寿命（尤其是存储寿命）的主要因素之一。为了从微观角度感知像增强器真空度的衰减机理，利用巨正则数值模拟了用于制造像增强器核心部件微通道板（MCPs）的硅酸铅玻璃的除气特性。蒙特卡罗和分子动力学方法。构建了第三代MCPs的玻璃结构模型，分析了氢气、二氧化碳、一氧化碳、水蒸气、氧气和甲烷气体的扩散系数和分子运动轨迹，以及它们的放气速率和累积放气量，是基于凝聚相优化分子势计算的，用于原子模拟研究力场。计算结果表明，MCP玻璃的温度升高增加了这些气体的扩散系数，使脱气率在初始阶段增加，然后相对较快地下降。在这六种气体分子中，氢分子的跳跃距离最大，扩散系数也最高，因为MCP玻璃可以为较小尺寸的气体分子提供更有效的扩散路径。当MCP玻璃处于真空状态时，首先从其中释放出的各种气体的累积释气量迅速增加，然后逐渐达到稳定值，