共查询到19条相似文献,搜索用时 609 毫秒
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陶瓷材料放气特性分析 总被引:2,自引:1,他引:1
利用自行研制的材料真空放气性能测试设备,对4种不同陶瓷材料样品在真空环境下的放气特性进行了测试,并对照各样品材料表明及断面扫描电镜的照片,进一步阐明了它们在高温条件下产生不同放气量的原因。 相似文献
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简介了测试扫屏放气性能的原理、装置、方法、数据处理过程与误差分析.应用研究表明,寿命初期(25 h内)的扫屏放气性能就能表征彩显管的真空质量,用它可判断或比较制屏工艺与材料(包括排气工艺与设备)的优劣,预估因真空因素导致失效的整管寿命水平.这种快速信息反馈方法,比"加速寿试"更能及时地反映工艺或材料变更对成品管带来的影响. 相似文献
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鉴别电真空用金属材料真空性能的好坏,对电真空器件的生产有直接帮助。通过分析金属高温出气的属性,研讨了一种比较实用的鉴别方法,提出了用材料的“本征放气量”和其对应的出气曲线作为衡量材料真空性能的标准,可以较全面地鉴别出材料的真空性能。 相似文献
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本文分析了微通道板(MCP)在烘烤和电子轰击下大量放气的机理,结合有关实验数据给出了放气成分及放气量的相对大小。指出:放出的这些气体不仅对光阴极有毒害,而且对MCP自身的次级电子发射性能还有不良影响,即降低次级电子产额。在此基础上提出了解决MCP大量放气的方法。 相似文献
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红外微型杜瓦真空退化特性研究综述 总被引:1,自引:0,他引:1
分析了导致真空失效的漏放气因素。通过超高灵敏度检漏技术,可以严格控制漏气对真空寿命的影响。用功率形式的放气模型 q(t)=q0(t/t0)-α描述了杜瓦真空夹层的放气率退化特性。用温度加速了杜瓦真空夹层内的真空退化进程。用阿列尼斯模型 q=q0exp(-E/RT)描述了温度对材料放气率的影响。根据理论分析和放气率实验,可确定出加速因子。 相似文献
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用四极滤质器对光电阴极碱源材料放气成分进行质谱分析,给出了分析结果,并对所放出有害气体给制备光电阴极带来的影响进行了讨论。 相似文献
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半球谐振陀螺是一种高精度长寿命的陀螺仪,具有小型化和轻量化的特点,最长具备连续工作15年的能力。随着半球陀螺的长时间工作,受材料放气和焊缝漏率的影响,真空度的下降对陀螺谐振子的精度影响逐渐增大,又因陀螺轻量化的要求,需要精确计算寿命期间的出气总量,以严格控制吸气剂的用量。该文分析了陀螺在工作过程中的出气类型,从材料放气、焊缝漏率、氢气渗透3个维度建立数学模型,得出工作过程中的出气总量,并建立陀螺流体模型,给出吸气剂的用量和初始工作条件。研究结果表明,对于吸气量大于4.12 Pa·L的半球陀螺,选用St172型吸气剂450 mg,可以满足长寿命工作的要求。本研究为半球谐振陀螺的长寿命真空保持提供理论。 相似文献
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《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2002,90(9):1604-1607
As part of an historical study of streetlighting in London (UK), the article examines how the gas discharge lamps of 1930 indicated the way ahead but were not the complete answer. They needed special circuits, with an inductance to control the current and usually some way of producing a high voltage to strike the arc, but the higher efficiency compared with filament lamps made that worthwhile. The real problems facing designers and manufacturers of discharge lamps were materials. They needed materials for the arc tube and for the electrodes that would resist chemical attack from the hot ionized gases in the tube. In any event, the high-pressure mercury lamp and the sodium lamp were developed almost simultaneously. Today these lamps dominate street lighting as well as flood light applications 相似文献
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就残余气体对微波电子管性能和寿命的影响进行了深入地研究。通过研究残余气体的成分,找到了减少各种气源漏气、渗气、放气的主要途径。在生产中,合理选材、优化工艺和加强质量控制,可以有效地减少残余气体,提高电子管寿命。 相似文献
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纳米粒子掺杂的液晶显示技术 总被引:1,自引:0,他引:1
液晶显示器需要快速响应来显示动态画面,纳米粒子掺杂技术能够改善液晶材料的特性,提高液晶显示器的光电性能。本文介绍了四种主要的掺杂纳米粒子类型:碳纳米管、金属纳米粒子、金属氧化物纳米粒子和铁电性纳米粒子。 相似文献
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Enhanced He-Ne gas laser stability has been achieved by constructing the mirror and gas discharge tube as an integral unit. The primary components are made from Corning ULE and 99JJW ultralow thermal expansion materials; ultrahigh-vacuum-type materials are used throughout. The ambient pressure sensitivity of these 6328-Å laser structures is 2.5 MHz/torr. Preliminary beat frequency measurements between two lasers, under pressure and temperature-controlled conditions, have yielded a beat frequency spectral width of the order of 2 kHz over an interval of 1 s. This result was achieved without the use of any elaborate sound or vibration isolation. Improved isolation reduced the spectral width to 100 Hz for a measurement duration of 0.02 s. The single-structure mirror-discharge tube has provided relative output power stabilities of better than 3 parts in 1000 over a period of 12 h. The frequency-modulation sensitivity is 1.2 kHz/μA of discharge current, from dc to 100 kHz. 相似文献
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Theory of long term gain growth in traveling wave tubes 总被引:1,自引:0,他引:1
The properties of the attenuator materials used in traveling wave tubes (TWT) are a major factor in determining the gain of the tube. Carbon is a commonly used attenuator material which is typically deposited on the dielectric rods used to support the helix slow wave structure in TWTs. The deposited carbon layers are susceptible to ion bombardment induced damage during operation and outgassing of the tube, which increases the electrical resistivity of the layer and reduces the rf loss in the tube. The total gain in the tube grows during this process until the bombardment ceases or the layer damage saturates. A simple theory is developed that relates this gain change to the gas evolved in the tube that results in the particle bombardment of the layers during operation. The model accurately describes the observed time dependent behavior of the gain, and the time constant for outgassing the tube is found for several tubes ranging from S to Ka band. The time constant increases significantly for smaller, high frequency tubes with a low conductance and poor pumping speeds. The model shows that stabilization of the gain occurs after several time constants have passed, which may take hundreds to thousands of hours 相似文献