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为满足惯性制导对高精度、高稳定度陀螺仪的需求,进行了对基于高色散谐振环结构的光纤陀螺原理研究.在一些高色散耦合谐振环结构中,其色散性质使其系统传递函数对相位微扰十分敏感,可以对萨格纳克相移起到放大作用,从而大大提高传感灵敏度.理论与仿真研究结果表明:多点耦合内切谐振环慢光结构系统能够同时满足实现高灵敏度转动传感所要求的“方向性条件”和“高群折射率(慢光)”两个基本条件,且具有进一步使群折射率比传统结构高出几个数量级的潜力.同时,由于该结构系统可使用定向耦合器来方便搭建,具有用来制作低成本、高灵敏度的光纤陀螺的潜力. 相似文献
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低温水相变制热系统与水源热泵机组相结合构成冰源热泵机组,采用TRNSYS软件对冰源热泵机组与地埋管地源热泵机组联合供暖系统的运行特性及能效进行仿真。水泵耗电量:低温水相变制热系统在供暖期并非始终保持满负荷的制冰状态,不同条件下平均含冰率均小于设定的峰值含冰率。在乙二醇溶液循环温差一定的条件下,冰浆循环泵耗电量随峰值含冰率增大呈下降趋势。乙二醇溶液泵耗电量随峰值含冰率的增大而增加。随着峰值含冰率的增大,乙二醇溶液泵耗电量在低乙二醇溶液循环温差下的上升趋势明显,在高乙二醇溶液循环温差下的上升趋势变缓。热泵机组耗电量:随着峰值含冰率增大,低温水相变制热系统承担了更多热负荷,冰源热泵机组耗电量呈上升趋势。峰值含冰率一定时,随着乙二醇溶液循环温差增大,冰源热泵机组耗电量呈下降趋势。地埋管地源热泵机组耗电量对峰值含冰率、乙二醇溶液循环温差的变化不敏感。机组能效比:与地埋管地源热泵机组相比,冰源热泵机组能效比受峰值含冰率、乙二醇溶液循环温差的影响更加明显。在低峰值含冰率下,比较高的乙二醇溶液循环温差对应较高的冰源热泵机组能效。在高峰值含冰率条件下,过低的乙二醇溶液循环温差不利于冰源热泵机组能效的提高... 相似文献
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The areal distribution of some elements in the rare earth bearing spheroidal phases in pure aluminium andAl-Mn alloys was studied by SIMS(secondary ion mass spectrometry).The results show that cerium,iron.silicon and hydrogen are significantly segregated in the phases.Thus the existence of hydrogen-rich rare earthbearing eompounds is confirmed.It indicates that the rare earths have a hydrogen fixation effect in aluminiumand aluminium alloys. 相似文献
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The effect of mischmetal addition on lead segregation in high lead bronze(grade ZQPb25-5)is studied inthis paper.The testing results confirm that 0.5 to 1.0% misehmetal addition can effectively prevent lead fromgravity and inverse segregation.The results of preventing lead from segregation respectively by mischmetal andnickel are also compared in the paper.The mischmetal addition in high lead bronze is distributed in the coppermatrix mainly in the form of a compound which promotes early precipitation and refinement of α-dendrites,thus restraining the Pb-rich melt from either sinking to the bottom or escaping to the surface layer of thecasting.As a result,the tendency of lead segregation is significantly decreased.Proper addition of mischmetalcan also improve the mechanical properties,especially the ductility of high lead bronze.In addition,the contentsof tin in high lead bronze can partially be substituted by mischmetal addition. 相似文献
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中央空调素有“建筑物之肺”的美称,如果这个“肺”长期得不到清洗,就会成为一个大污染源。目前,大连市已经出现空调清洗专业公司,有的公司还配备了管道清洁机器人。但大连市这一新兴行业正面临进退两难的窘境——很少有人愿意花钱清洗中央空调。 相似文献
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用碱性熔盐作为载体将Al_2O_3粒子较均匀地添加到铝合金熔体中是获得Al_2O_3粒子增强铝基复合材料的新方法。本文对比了熔盐种类、配比、加入方法及Al_2O_3粒子大小对其在铝基体中分布均匀性的影响,测定了Al_2O_3粒子强化铝基铸选复合材料的机械性能。 相似文献