超宽连续谱产生的实验研究

本文首次报道了利用强激光先后连续泵浦两种不同的光纤，产生了带宽为１００ｎｍ的宽带连续辐射谱的方法，并解释了实验结果。     

关于长方矩阵的Г-Drazin逆和柱心-幂零分解

1引言及准备在[1]中,R．E．Cline和T．N．E．Greville讨论了长方矩阵的带W权Drazin逆．本文在上述研究的基础上研究讨论长方矩阵的更加广泛的带权Drazin逆,用[2]中的术语称之为Г-Drazin逆．这些理论在约束线性方程理论、人口增长模型和最优化控制等方面有     

Experimental investigation of interparticle collision in the upper dilute zone of a cold CFB riser

Interparticle collision plays an important role in the mechanics of gas–solid two-phase flows. The paper presents direct measurements of collision rate as well as collision properties of spherical glass beads with sizes of 500 ± 50 μm in the upper dilute zone of a cold pilot-scale CFB riser, by using a high-speed imaging system. The recording rate of the high-speed digital camera is as high as 5000 fps with a resolution of 640 × 480. A large number of particle movement images at a height of 3.54 m above the distributor plates were taken. Manual inspection and automatic methods based on digital image processing algorithms were carried out to analyze particle image sequences. The experimental results show that the measured particle collision rate is proportional both to the particles’ average relative translational velocity and the square of the particle number density, which coincides with the collision theory derived according to the analogy of kinetic theory of gases. But the theoretical model is found to overestimate the real collision rates, and a coefficient a of 0.33 may be used to correct this discrepancy. The possible reasons for this discrepancy are also discussed. The measurement results of collision properties based on more than 50 particle collision events agrees well with Walton’s hard-sphere collision model. The three collision parameters, i.e., the average coefficient of friction μ, the normal and tangential coefficients of restitution e and β₀, for the glass beads used are measured to be 0.175 ± 0.005, 0.96 ± 0.02, and 0.43 ± 0.09, respectively.     

气固两相流动的湍流脉动扩散数学模型及其应用

本文提出了气固两相流动的湍流扩展数学模型，本模型用k-ε双方程模型求解气相湍流场，并根据气流脉动的频谱、能谱曲线提出了随机富工级数来模拟气相脉动速度，用拉氏方法描述颗粒的运动，故称为脉动频谱随机颗粒轨道模型。本文还给出了本模型在气固多相射流和流化床内应用的实例。     

利用可调谐半导体激光光谱技术对含尘气体中NH3的测量

利用可调谐半导体激光吸收光谱技术（TDLAS）并结合波长调制，在近红外波段1531.7nm处对常温常压下的NH₃进行浓度测量.在10m的长程吸收池内得到了25×10^-6的浓度信号，并且在25×10^-6—400×10^-6浓度范围内二次谐波信号与浓度具有良好的线性关系.讨论了粉尘颗粒对于二次谐波信号的干扰，并提出了利用激光强度线性拟合解决颗粒对气体测量干扰的方法. 关键词： 可调谐半导体吸收光谱 波长调制 3浓度测量')" href="#">NH₃浓度测量 颗粒影响     

Lower bound limit analysis of three-dimensional elastoplastic structures by boundary element method

IntroductionThelimitanalysisofstructuresisoneofthemostpracticalandusefulbranchesinplasticity .Ithasimportantapplicationbackgroundforproblemssuchasthedeterminationofloadcarryingcapacityandplasticformingofmetal.Thepurposeofthelimitanalysisofstructuresistoprovidereliabletheoreticalbasesforengineeringdesignandsafetyassessment.Asasimplifiedmethodforelastoplasticproblems,limitanalysisneednotrequirethehistoryofloadandcancomputethelimitloadsdirectlyinsteadofelastoplasticincrementalcomputationwhichisus…     

Preparation of slightly crosslinked monodisperse poly(maleic anhydride-cyclohexyl vinyl ether-divinylbenzene)functional microspheres with anhydride groups via precipitation polymerization

Slightly crosslinked monodisperse poly（maleic anhydride-cyclohexyl vinyl ether-divinylbenzene）（MA-CHVE-DVB） microspheres were prepared via precipitation polymerization while using 2,2-azobisisobutyronitrile as an initiator in a mixture of methyl ethyl ketone and n-heptane without any stabilizer.The number-average diameter of the resultant poly（MA-CHVE-DVB） microspheres ranged from 0.478 to 1.386 μm with a polydispersity index of 1.00 to 1.02 that depended on the feed ratios of the MA/CHVE/DVB monomers.The introduction of one electron donor monomer cyclohexyl vinyl ether strongly affected the yield,size,and morphology of these slightly crosslinked microspheres.Quinolinetype chelating resins were obtained after combining the poly（MA-CHVE-DVB） with 8-hydroxyquinoline;the adsorption properties of these materials were measured through their ability to remove Cu²⁺ ions from water.The poly（MA-CHVE-DVB） microspheres with low degrees of crosslinldng provided more effective functional groups and therefore better ion removal capabilities.These slightly crosslinked microspheres may have applications in water treatment as well as in sensing and drug delivery.     

固支及简支圆板在均布侧压作用下的弹脆塑性承载能力分析

圆板是工程中常见的一种结构形式。本文采用弹脆塑性木构模型，对弹塑性载荷作用下固支圆板的弯曲作了详细的分析研究，得出了对应材料残余强度系数不同取值范围的图板的承载能力解析表达式。文中对加载过程中屈服面的变化情况作了探讨。文未还给出了相应的简支圆板的弹脆塑性承载能力表达式。     

考虑摩擦作用闭合裂纹应力强度因子计算的边界元分区算法

本文采用边界元分区算法研究考虑摩擦的闭合裂纹问题,简单裂纹系问题及非均匀介质中裂纹问题.在裂纹尖端采用了1/4面力奇异单元,并对相应的奇异积分给出了数值处理.对于复杂载荷下裂纹面计算给出了增量迭代算法,并采用方程减缩技术使迭代仅在裂纹上进行.计算实例表明方法是可行的.