小型撬装式BOG再液化装置的研发及性能测试

以最新研制的大功率回热式脉管制冷机为核心,建立了一台小型撬装式BOG(Boiled off Gas)再液化实验装置。与传统的BOG再液化装置相比,该装置具有结构紧凑、操作简单、经济效益好等优点。通过测试实验,0.4MPa时,在9400W的电机功率下,该装置制冷功率达到267W@86K;对制冷机冷头和冷屏进行改进后,在8450W的电机功率下,该装置在0.3MPa时的制冷功率达到430W@83K。实验结果表明:对制冷机冷头和冷屏进行优化后,装置的有效制冷功率大幅提高。     

Observation of insulating–insulating monoclinic structural transition in macro‐sized VO2 single crystals [Phys. Status Solidi RRL 5, No. 3, R107–R109 (2011)]

In our article, we reported the observation of monoclinic M2 to M1 structural phase transition in VO₂ single crystal near the temperature of ～49 °C. However, the re‐examination of Laue patterns reveals that previously defined monoclinic M1 and M2 phases can be interpreted as monoclinic M2 and triclinic T phases instead. Careful experimental geometry calibration and further refinement of the lattice parameter ratios and angles show that monoclinic M2 and triclinic T phases fit better with the experimental data. On the other hand, our previous misidentification of the insulating phases does NOT affect the conclusions of our article. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)     

阻性管道消声器消声量方程的一个新算法

将阻性管道消声器消声量特征方程（组）转化为常微分方程（组），由此给出消声量计算的一个新方法。该方法毋需迭代因而不存在计算稳定性问题，计算量小，初值的迭取也很简单，适合于扁矩形、任意矩形及圆形等各种截面管道消声器，尤其对多变量、考虑平均流影响的情形更为有效。     

空间光学遥感器热试验外热流模拟及程控实现

以某太阳同步轨道空间光学遥感器为例,阐述了空间外热流分析计算、热平衡试验外热流模拟以及外热流程控加载的全过程.首先,总结了空间光学遥感器外热流模拟的完整流程.其次,简要介绍了太阳辐射、地球反照、地球红外辐射三种空间外热流的计算方法.然后,对该空间遥感器进行了空间综合吸收外热流计算,获得了阳照区及阴影区外热流平均值.最后,确定了热平衡试验外热流的模拟方法和策略,利用LabVIEW语言编写了程控电源开环控制程序,实现了热试验外热流的准确加载.试验结果表明,外热流值加载偏差在±2.5%以内,满足热平衡试验要求.     

Room temperature single-frequency output at 2118 nm from a diode-pumped Tm,Ho:YAP laser

A diode end-pumped single-frequency Tm, Ho:YAP laser at room temperature was reported. We demonstrated a single-frequency Tm, Ho:YAP laser at 2118.09 nm wavelength with output power up to 57 mW using two Fabry-Perot intracavity etalons. The optical conversion efficiency is 2.0% and the slope efficiency is 12.7%. The measured full width at half maximum linewidth was <7.5 pm limited by the resolution of the scanning Fabry-Perot etalon used to make the measurement. The wavelength was demonstrated to be stable to about 2 pm over 40 s time periods limited by the temperature stability of the laser. The single-longitudinal-mode (SLM) laser can be used as a seed laser for coherent wind measurements and differential absorption LIDAR systems.     

Agitation-free multiphoton microscopy of oblique planes

The scanning two-photon fluorescence microscope produces optically sectioned images from the focal plane. It is sometimes desirable to acquire images from other planes of the specimen that are inclined with respect to the focal plane. In this Letter, we discuss the issues concerned with acquiring such images together with the effects of the inclination angle on image resolution and sectioning strength. To obtain images from oblique planes at high speed, a two-photon system was built wherein a novel optical system is used to provide aberration-free scanning.     

Mechanism of local stress release in armchair single-wall zinc oxide nanotube under tensile loading

The deformation mechanism of zinc oxide (ZnO) nanotube has been first examined by molecular dynamics. The result demonstrated that ZnO nanotubes relax it excess strain via the phase transformation from an armchair structure to a fourfold-coordinated structure, then to a zigzag structure, which is started by a slip deformation. In contrast to carbon, silicon carbide, and boron nitride nanotubes, they relax it local stress via the transformation of the Stone?CWales transformation. After yielding, the 8-4 dislocation loops are found and the numbers of 8-4 dislocation loops grow up, which relax the tensile strain at the necking region and leads the work hardening. Finally, the nanotube is broken down by crack deformation at the interface between different phases.