Numerical modelling for scattering of waves in three-dimensional cracked material

In this paper, a mathematical model is proposed for the problem of the scattering of plane waves in a three-dimensional cracked materials. Instead of obtaining closed-form solutions as in conventional theoretical analysis methods, this approach, called the Equivalent Nodal Force (ENF) method formulates the mechanical effects of cracks as an equivalent nodal force in a numerical procedure, and physically translates cracked material into an equivalent continuous one. Several mechanical relations between waves and cracks are evident from this method. Also the results of several numerical calculations are presented and these are compared with those obtained by the conventional methods.     

位置灵敏探测器数据采集的软件设计

介绍了一个基于Windows操作系统的数据采集软件，该软件用于使用重心法确定的位置信息的位置灵敏探测器，具有方便的人机交互界面，使用专用驱动程序采集数据。     

Thermodynamic Analysis of Various Dehumidifying Dryers for Wood

Typical methods of dehumidification of air circulating in the dehumidifying driers (indirect and direct cooler and partial exchange of the air) were analysed. Energy aspect of cooler operation was evaluated. The method for minimization of unit thermal energy consumption in a dehumidifying drier by the optimal selection of the cooler point was also given. Methods of the heat recovery of heat conveyed in a cooler lending to save energy (heat regeneration. expansion and compression of the air, a dehumidifier) were analysed. It was indicated that introduction of dehumidifiers into contemporary wood driers caused significant improvement of energy aspects of their operation     

Phase equilibria in InAsSbP quaternary alloys grown by liquid phase epitaxy

The quaternary alloy InAs_1−x−ySb_xP_y, lattice-matched to InAs, is a promising material for the production of infrared light sources for the detection of gases in the 2–4 μm region of the spectrum. In this work, thermodynamic phase equilibrium calculations have been carried out to determine the compositions required for liquid phase epitaxial growth and the extent of the miscibility gap in the solid material. For high band gap materials, the desired growth temperature is found to be intermediate between a low temperature required to grow P-rich solids and higher temperatures required to avoidspinodal decomposition. Conventional LPE growth at an intermediate temperature of 583°C is found to produce good material with high luminescence efficiency and excellent optical characteristics. Problems with phosphorus loss from the melt are also discussed and lower growth temperatures are found to considerably reduce this problem. Growth in the metastable region between the binodal and spinodal lines has been achieved with the production of phosphorus-rich solids with concentrations up to y = 0.445.     

沈阳太平洋广场空调冷热源方案比较

对一幢１１．５万ｍ＾２的四星级综合建筑的空调冷热源不同的蓄冷和取冷比较了四种方案，论证了其中直燃型溴化锂吸收式冷热水机组供冷供暖、小型燃油锅炉供蒸汽的方案最为合理。     

含氮化合物废气选择性催化氧化技术研究进展

通过对当前含氮化合物废气治理技术的对比分析,总结选择性催化氧化的相关技术优势。根据对含氮化合物的种类及来源分析,介绍氨气、腈类、胺类及其他含氮化合物的催化净化技术。重点总结催化剂的种类、研发进展和在实际使用中可能遇到的问题,同时展望含氮化合物废气选择性催化氧化技术的研发方向。     

The effect of pre-wetting on dynamic contact angles

A roll-coating experimental system is used to study the effect of pre-wetting on dynamic contact angles, the interfacial displacement depth, and the associated phenomenon of air entrainment. The system consists of a roll, which is horizontally rotating in a liquid pool. The dynamic contact angle is recorded by a macrophotography system. The test liquids are glycerol solutions with viscosities in the range 104 < μ < 748 mPa · s. The value of (μV/ρg)^0.5 is taken as the characteristic length to be used in the dimensionless relationships which correlate experimental measurements. The effect of base layer entry angle into the liquid pool on the dynamic contact angles and other flow parameters is studied. Comparison is made with measurements in dry tape-coating and other pre-wet roll–coating systems.     

氢/空气火焰在半开口有障碍管道中的传播特性

针对氢／空气混合物，通过实验研究了其预混火焰在半开口管道中的火焰传播加速现象。结果表明，火焰传播状态随着氢气当量比的变化而发生改变。当氢／空气混合物被点燃后，由于障碍物的扰动，火焰在管道中不断加速传播，并最终到达一准稳态传播。在氢气当量比0．34附近时，火焰速度发生跃变。当氢气当量比足够大时，火焰传播由爆燃态转变为爆轰态。在本实验条件下，爆燃转准爆轰的临界条件是d/λ=2.6(d是圆环形障碍物内径，λ是爆轰格胞尺度）。障碍物阻塞比的变化对最大火焰速度和压力提升的影响不明显。     

Boundary trend of α1/(α1 +α2) phase region at lower Cu side in Al-Zn-Cu system

The range of miscibility gap above 300 ℃ at low Cu side in Al-Cu-Zn ternary system was obtained by EPMA of the designed alloys and diffusion-couples treated for equilibrium. The results about the boundary trend of the α1 / (α1 α2 ) phase region was obtained. The α1 / (α1 α2 ) boundary moves towards the lower Zn side with the increase of Cu content. The results are opposite to traditional phase diagrams obtained by experiments, but consistent with recent thermodynamic calculations.     

某医院净化手术部空调设计

介绍了各净化间的设计参数，送、回、排风系统和自控系统的设计，以及运行情况。探讨了基于手术部湿度优先控制模式下的新风系统的设计及控制。