AuSn焊料组分对半导体激光器件性能的影响

为了提高半导体激光器件的可靠性,研究了AlN过渡热沉上AuSn焊料不同配比对半导体激光器器件性能的影响。利用MOCVD 生长975 nm芯片,通过对半导体激光器器件表面形貌、空洞、光谱特性、热阻特性以及寿命测试,Au组分比重低于72%的AlN过渡热沉封装器件表面颜色明显不同于组分相对较高的,空洞较多,平均波长红移约5 nm,在寿命试验中过早失效,最终得出AuSn焊料中Au组分比重最好大于72%,小于80%,才能保证封装器件焊接质量,为实际生产和使用提供了指导意义。     

倒立式三视场施密特望远镜关键技术研究

研制了基于三分区镜的倒立式三视场施密特型望远镜，对其关键技术进行了分析。利用正三棱锥的几何对称性，推导了3个视场的视轴夹角与分区镜面夹角之间的关系式，设计了用于实现多视场观测功能的三分区镜；通过有限元法分析了倒立式施密特望远镜主镜重力形变对像质的影响，阐述了检测光路关键参数对施密特修正镜加工误差的影响程度，采用蒙特卡罗法对该光学系统的杂散光进行了分析。最后对整个光学系统进行了实验检测，检测结果表明：实际研制的三分区镜镜面之间的夹角为133.08°，可同时对相互垂直的3个视场进行观测；该望远镜光学系统的PV=0.614λ，RMS=0.105λ(λ=632.8 nm)。该系统可用于地球空间姿态测量，拓展了施密特望远镜的应用范围。     

Molecular dynamics simulation of interaction between nanorod and phospholipid molecules bilayer

Natural and artificially prepared nanorods' surfaces have proved to have good bactericidal effect and self-cleaning property. In order to investigate whether nanorods can kill the enveloped virus, like destroying bacterial cell, we study the interaction between nanorods and virus envelope by establishing the models of nanorods with different sizes as well as the planar membrane and vesicle under the Dry Martini force field of molecular dynamics simulation. The results show that owing to the van der Waals attraction between nanorods and the tail hydrocarbon chain groups of phospholipid molecules, the phospholipid molecules on virus envelope are adsorbed to nanorods on a large scale. This process will increase the surface tension of lipid membrane and reduce the order of lipid molecules, resulting in irreparable damage to planar lipid membrane. Nanorods with different diameters have different effects on vesicle envelope, the larger the diameter of nanorod, the weaker the van der Waals effect on the unit cross-sectional area is and the smaller the degree of vesicle deformation. There is synergy between the nanorods in the nanorod array, which can enhance the speed and scale of lipid adsorption. The vesicle adsorbed in the array are difficult to desorb, and even if desorbed, vesicle will be seriously damaged. The deformation rate of the vesicle adsorbed in the nanorod array exceeds 100%, implying that the nanorod array has a strong destructive effect on the vesicle. This preliminarily proves the feasibility of nanorod array on a surface against enveloped virus, and provides a reference for the design of corresponding nanorods surface.     

磷钼杂多酸对纤维素水解产物分布及水解过程的影响

本文用自制玉米秸秆纤维素作为原料，以Wells Dawson型磷钼杂多酸H₆P₂Mo₁₈O₆₂(Phosphomolybdic acid, PMA)作为催化剂，在水热条件下降解纤维素，考察反应温度、反应时间、料液比和催化剂用量对纤维素转化率及液化产物分布的影响，并探究PMA在水解过程中发挥的机理作用，得到最佳反应条件：反应温度220℃,反应时间60 min,料液比1∶50,催化剂用量1 g,此条件下羟基乙酸、乳酸、甲酸和乙酰丙酸产率分别达到13.69%、4.15%、4.83%和4.34%。结果表明，PMA在纤维素水解实验中表现出很大的潜力，可作为非均相固体酸催化剂用于羟基乙酸生产。     

里德伯原子辅助光力系统的完美光力诱导透明及慢光效应

光力诱导透明是典型的量子相消干涉效应,在量子光学和量子信息处理当中具有广泛的应用.本文在里德伯原子系综镶嵌的复合光力学系统中考察了光力诱导透明现象以及由此产生的慢光效应.当考虑非旋转波近似的情况下,可以获得完美的光力诱导透明,即非常狭窄的理想透明窗口.在可分辨边带条件下,微腔品质越高,完美透明窗口中的慢光效应越明显.特别地,与其他原子相比,在实现超慢光方面里德伯原子的长寿命体现了其优越性.     

Nonreciprocal Phonon Laser in an Asymmetric Cavity with an Atomic Ensemble

Phonon lasers, as a novel kind of lasers for generating coherent sound oscillation, has attracted extensive attention. Here, we theoretically propose a nonreciprocal phonon laser in a hybrid optomechanical system, which is composed of an asymmetric Fabry–Pérot cavity, an ensemble of N identical two-level atoms, and a mechanical oscillator. The effective driving amplitude related to driving direction leads to an obvious difference in mechanical gain and threshold power, bringing about a nonrecipr...     

鼻黏膜纤毛显微内窥镜光学系统设计

为了实现从前鼻孔进镜对鼻黏膜表面进行直接显微成像，从而进行无创性观察和测量在体鼻纤毛运动，设计了一种能够分辨鼻纤毛，并且带有30°视向角的变倍硬性显微内窥镜。所设计的硬性内窥镜系统物方数值孔径为0.15，分辨率为272 lp/mm，工作距离为3.00 mm，视向角为30°，物面高度为0.40 mm，系统总长度为205.62 mm，物方口径为4.65 mm，放大倍率为6×～10×。此鼻黏膜纤毛显微内窥镜将可以避免取材造成的纤毛功能损害和受试者痛苦，极大地提高纤毛相关疾病的临床诊断能力，成为助益纤毛领域科研和临床工作的重要突破。