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在不改变任何设备、只部分换用AQ - 1型氨合成触媒的情况下 ,使合成氨生产能力提高了 10 % ,吨氨电耗和能耗均有所下降 ,取得了令人满意的效果。 相似文献
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The 500 MHz 5-cell superconducting RF(SRF) cavity was designed aiming to be a candidate cavity for high current accelerators. A copper prototype cavity and a niobium cavity were fabricated at SINAP in 2012. In order to ensure these cavities get the desired frequency and a good field flatness higher than 98%, frequency control was implemented in the manufacturing process and pre-tuning has been done using a simple pre-tuning frame based on the bead-pull pre-tuning method. Then, TM010-π mode frequency within 5 kHz from the target frequency was achieved and the field flatness reached 98.9% on the copper prototype cavity. Finally, the same procedure was applied to the niobium cavity to obtain a field flatness better than 98% which benefited the cavity performance in the vertical testing. 相似文献
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卫星导航系统安全防护对导航以及武器装备具有极其重要的意义。首先介绍了卫星导航系统安全防护的定义、描述和研究内容;然后根据系统工程思想,给出了研究卫星导航系统安全防护问题的一般思路;接着给出了一个综合考虑干扰策略、攻击水平、防护水平、作战场景等安全防护因素的数学模型;最后通过算例分析了接收机的安全防护。实验结论显示,相对于敌方攻击水平的防护水平是影响我方作战效用的关键因素,不同作战任务场景对安全防护的要求是不同的,攻击策略对作战效能的影响取决于相应防护水平的强弱。 相似文献
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上海光源是第三代同步辐射光源。在上海光源的二期工程中,超导三次谐波腔将用于拉伸束团长度,提升束流托歇克寿命。三次谐波腔工作在被动模式下,谐波腔工作频率(约1.5 GHz)为主腔工作频率(约500 MHz)的三倍。为实现谐波腔高频系统的调谐控制,需要对1.5 GHz信号进行下变频处理,便于后端对信号采样处理。本文介绍了三种下变频的方案,将1.5 GHz射频信号降频为31.25 MHz中频信号,分析了各个方案的特点和影响下变频结果的因素。测试结果显示:三种变频方案在不同的动态范围具有良好的线性,均已满足谐波腔控制需求。其中基于倍频器的变频模块为最优方案,其线性动态区间大于70 dB,同时产生的中频信号的相位噪声最低,最终将在谐波腔的控制系统中采用。 相似文献
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Surface preparation is an important processing in production procedures of superconducting niobium cavities,deciding whether the performance of the niobium cavities can meet the specifications. A series of surface preparation methods and relevant apparatuses have been constructed at Shanghai Institute of Applied Physics(SINAP) and the standard procedures of cavity processing were established and successfully applied to different types of cavities. With standard surface preparation procedures on the 500 MHz 5-cell niobium cavity, the cavity accelerating voltage at T = 4.2 K reached 7.5 MV while its quality factor was still higher than 1 × 109.The accelerating gradient of the IMP-HWR010 cavity reached 4.9 MV/m with the quality factor of better than3 × 108 at 4.2 K. 相似文献