掺铬镁橄榄石作为1.06μm激光可饱和吸收体的研究

采用Cr4 :Mg2SiO4作为可饱和吸收体,实现脉冲式平凸非稳腔Nd:YAG激光器的被动调Q运转,得到脉宽34ns、输出能量13.8mJ的激光脉冲。在合适的实验条件下,也观察到被动锁模现象。实验上比较了激光器的不同腔结构和参数对调Q激光脉冲宽度和能量的影响,并给予合理的理论解释。     

对风力发电场稳态时不同等值模型的研究

对风电场稳态情况下建立不同的降阶等值模型进行了讨论,利用对风力发电机电气参数的有效等值进行实例仿真,验证了这些等值的正确性,为含风电的电力系统提供了参考。     

Secure quantum report with authentication based on six-particle cluster state and entanglement swapping

A novel high-efficient secure quantum report with authentication based on six-particle cluster state and entanglement swapping is proposed.In our protocol,using N groups of six-particle cluster state,the legitimate users Bob and Charlie send their secret reports to their boss(Alice),who operates sixteen kinds of unitary operations after receiving the reports.Here,entanglement swapping of cluster states and maximum entanglement state measurement are employed by the communicators.It has been proved that our protocol has high level guarantees and honesty,and the scheme is secure not only against the intercept-and-resend attack but also against disturbance attack.     

耐磨陶瓷复合技术在风机转子上的应用

为解决排粉风机叶轮的磨损问题，探讨了采用陶瓷-金属复合制造技术的可行性，介绍了复合层胶粘剂的性能校核及选用，对实际运行效果进行了分析，得出了其使用寿命比原来的喷焊或堆焊工艺提高了5倍以上的结论。     

A multiphase mesostructure mechanics approach to the study of the fracture-damage behavior of concrete

A multiphase mesostructure mechanical model is proposed to study the deformation and failure process of concrete considering its heterogeneity at the meso scopic level.Herein,concrete is taken as a type of three-component composite material composed of mortar matrix,aggregates and interfaces on the meso-scale.First,an efficient approach to the disposition of aggregates of concrete and a state matrix method to generate mesh coordinates for aggregates are proposed.Secondly,based on the nonlinear continuum dam...     

A multiphase mesostructure mechanics approach to the study of the fracture-damage behavior of concrete

A multiphase mesostructure mechanical model is proposed to study the deformation and failure process of concrete considering its heterogeneity at the meso scopic level. Herein, concrete is taken as a type of three-component composite material composed of mortar matrix, aggregates and interfaces on the meso-scale. First, an efficient approach to the disposition of aggregates of concrete and a state matrix method to generate mesh coordinates for aggregates are proposed. Secondly, based on the nonlinear continuum damage mechanics, a meso-scale finite element model is presented with damage softening stress-strain relationship for describing the mechanical behavior of different components of concrete. In this method, heterogeneities of each component in the concrete are considered by assuming the material properties of three components conform to the Weibull distribution law. Finally, based on this multiphase meso-mechanics model, a simulation analysis of fracture behavior of a rock-fill concrete (RFC) beam is accomplished. The study includes experimental tests for determining basic mechanical parameters of three components of RFC and four-point flexural beam tests for verification of the model. It is preliminarily shown that the numerical model is applicable to studying failure mechanisms and process of concrete type material.

     

空调系统运行方式对单室火灾发展的影响

以某高层建筑的单室空调房间为研究对象，利用计算流体软件PHOENICS，分别对空调系统、排烟系统、兼用系统等空调系统的不同运行工况下单室火灾发展过程进行了数值模拟计算；分析火灾后空调、防排烟兼用系统对单室空调房间火灾发展，以及对室内人员疏散产生的影响．模拟计算的结果证明了兼用系统火灾后在排烟、降温、减压、增加疏散时间等方面的实用性和可行性．