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理论仿真和实验制备了AlGaInAs/InP材料1.55 μm小发散角量子阱激光器。为了扩展近场光场并减小内损耗,将一个非对称模式扩展层插入到外延结构的下盖层当中。仿真结果表明,该模式扩展层除了少量增加激光器阈值电流以外,在不影响激光器其它性能的情况下能显著减小激光器的垂直远场发散角。实验结果与理论仿真高度吻合。成功制备出脊宽4 μm,腔长1000 μm的脊波导小发散角激光器。在端面未镀膜的情况下,该激光器阈值电流为56 mA,输出功率为17.38 mw@120 mA,斜率效率可以达到0.272 W/A。实验测得垂直远场发散角为29.6°,相比较传统激光器减小了约35.3%。 相似文献
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介绍了煤和废塑料共液化的机理、工艺条件以及近期的研究结果,并为今后的深入研究提供了思路。 相似文献
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The coupling cavity theory is used to analyze the impact of high side mode suppression ratio (SMSR) on fiber grating external cavity semiconductor lasers (FGECSL). The high SMSR and high stable frequency FGECSLs were obtained by experiment. The center wavelength is 974 nm, SMSR is 45 dB, the center wavelength change rate reaches 3.08 ppm/℃ in the temperature range of -20 to 80 ℃. 相似文献
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就工程资料的管理、收集、归档各环节存在的一些普遍问题,通过分析问题产生的原因,提出了相应的解决措施。提出工程资料真实、准确、完整、规范,才能确保工程质量有据可查。 相似文献
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工程变更管理是施工过程合同管理的重要内容,工程变更常伴随着合同价格的调整,是合同双方利益的焦点,因此,合理确定并及时处理好工程变更,可以减少不必要的纠纷,保证合同的顺利实施。 相似文献
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中国发展进入中国特色社会主义新时代,更加经济发展的质量,因此在现行国家政策和社会的要求下,企业越来越重视生产安全问题,意识到安全是第一要务。随着社会的发展,企业不仅需要为国家经济发展做出贡献,承担经济责任,还需要承担相应的政治责任和社会责任,三种责任应该是相辅相成、互为一体的,因此在企业内推行安全文化是大势所趋,要让每名员工树立较高的安全意识,在生产过程中首先要保障自身安全。本文将基于基层HSE管理体系构建的必要性,探讨HSE管理体系的推进策略。 相似文献
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用高低温循环加速试验评估光源模块长期贮存寿命的研究 总被引:1,自引:0,他引:1
Light source modules are the most crucial and fragile devices that affect the life and reliability of the interferometric fiber optic gyroscope (IFOG). While the light emitting chips were stable in most cases, the module packaging proved to be less satisfactory. In long-term storage or the working environment, the ambient temperature changes constantly and thus the packaging and coupling performance of light source modules are more likely to degrade slowly due to different materials with different coefficients of thermal expansion in the bonding interface. A constant temperature accelerated life test cannot evaluate the impact of temperature variation on the performance of a module package, so the temperature cycling accelerated life test was studied. The main failure mechanism affecting light source modules is package failure due to solder fatigue failure including a fiber coupling shift, loss of cooling efficiency and thermal resistor degradation, so the Norris-Landzberg model was used to model solder fatigue life and determine the activation energy related to solder fatigue failure mechanism. By analyzing the test data, activation energy was determined and then the mean life of light source modules in different storage environments with a continuously changing temperature was simulated, which has provided direct reference data for the storage life prediction of IFOG. 相似文献
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