BUBBLE TEMPERATURE MEASUREMENTS ON THE BINARY MIXTURES OF 1,4-DIMETHYLBENZENE WITH ISO -, SEC -, AND TERT - BUTANOLS AT 95 kPa

Bubble temperatures at 95 kPa over the entire composition range were measured for the three binary systems formed by 1,4-dimethylbenzene with iso-, sec-, and tert- butanols. A Swietoslawski-type ebulliometer was used for the measurements. The composition versus temperature measurements are well represented by the Wilson model.     

Ozonation Kinetics of Acid Red 27 Azo Dye: A Novel Methodology Based on Artificial Neural Networks for the Determination of Dynamic Kinetic Constants in Bubble Column Reactors

A procedure for the determination of initial parameter values for quadratically convergent optimization methods is proposed using artificial neural networks coupled with a non-stationary gas-liquid reaction model. The evaluation of the regression and the mean squared error coefficients of the neural network during its training process allow the parameter sensitivity analysis of the gas-liquid model. This analysis examines how many and which parameters of the model will be available depending on the observable information of the mathematical model. Numerical simulations show the relevance of the initial values and the non-linearity of the objective function. The methodology has been applied to the study of the reaction of the azo-dye Acid Red 27 with ozone in acid media. The rate constant is in the order of (1.6 ± 0.1) 10³ M^?1 s^?1 under the experimental conditions.     

Power‐law conductivity in polythiophene/copper(II) acetylacetonate composites

This paper reports the charge transport mechanism of polythiophene (PT) matrix composites having various concentrations of copper(II) acetylacetonate. Characterization and structural analyses of the samples were carried out via Fourier transform infrared spectroscopy, atomic absorption spectroscopy, differential scanning calorimetry, thermogravimetric analysis and scanning electron microscopy (SEM). The alternating current electrical properties were investigated as a function of temperature. The change of free energy of adsorption calculated from the Langmuir adsorption isotherm showed that metal ions were electrostatically adsorbed onto polymer chains. Significant morphological changes were observed from SEM images of PT depending on doping process which in turn affected the thermal degradation of PT. The charge transport mechanism determined from a power law showed that there was one frequency‐dependent conductivity region for PT, while there were two regions for the composites in contrast to studies reported in the literature. © 2013 Society of Chemical Industry     

梯形轨枕竖向振动模态分析

梯形轨枕轨道作为一种新型的轨道结构,是基于纵枕轨道理论的基础研制的,在很多方面弥补了传统横向轨枕的不足,但其自身特点还有待进一步研究。已有的研究大多集中在静力方面,高速列车的发展引发的种种问题使得动力问题越来越突出。为了充分了解梯形轨枕的动力特性,并为进一步分析梯形轨枕轨道打下基础,论文对梯形轨枕的竖向振动模态进行分析,得到了其固有频率和振型,分析结果表明梯形轨枕具有整体性和传递性的特点。     

频差3～40MHz的HeNe双频激光器

报道了自行研制的3－40MHz频差的双频激光器。用两种方法成功地得到3－40MHz的频差：第一种方法是将寻常光（o光）２和非寻常光（e光）２在空间分离,使其各自使用各自行进进路径上的放大Ｎe原子介质;第二种方法是对双折射双频激光器外加横向磁场,将放大Ｎe原子介质分成两类,一类只放大o光,另一类只放大e光。     

CHARACTERISTICS OF MICROCUTTING FORCE VARIATION IN ULTRAPRECISION DIAMOND TURNING

An investigation of the characteristics of microcutting forces in diamond turning of crystalline materials is presented. The characteristics of the cutting forces were extracted and analyzed using statistical and spectrum analysis methods. A series of cutting experiments were done on a copper alloy and copper single crystals with different crystallographic orientations. Experimental results indicate that there exists a dominant frequency component and a periodicity of fluctuation of the cutting forces per workpiece revolution in the diamond turning of a single crystal material. The periodicity is closely related to the crystallographic orientation of the material being cut. As the depth of cut increases, the influence of crystallographic orientation of the single-crystal materials on microcutting forces is found to be more pronounced. Moreover, the cutting force ratio between the mean thrust force and the mean cutting force is found to vary with the depth of cut, and a large ratio was observed at a small depth of cut. These findings help to explain quantitatively the periodic fluctuations of microcutting forces (and hence the materials-induced vibration) in ultraprecision diamond turning, which are not encountered in conventional machining.     

球平面开放腔设计与Q值测量

本文介绍了设计及测试球平面准光学开放腔(准光腔)的过程,对腔内稳定振荡场分布、菲涅尔数进行了细致分析,阐述了球平面准光腔的设计制作要点,介绍了用于介质测试的准光腔扫频测量系统,并采用标量网络分析仪(SNA)对准光腔进行了品质因数测定.     

Experimental studies on the instabilities of viscous fingering in a Hele-Shaw cell

When air is injected into silicone oil contained in a horizontal Hele-Shaw cell, a single air bubble forms and grows showing various interesting phenomena. In this study the effects of the bubble front velocity, air injection velocity at a nozzle, fluid properties and cell depth on the stability of the growing bubble were investigated experimentally. By using the modified capillary number involving the aspect ratio, we obtained the onset conditions of the unstable bubble. Also, the bubble width was analyzed both quantitatively and qualitatively. Before the bubble experiences splitting, the bubble front velocity is almost proportional to the air injection velocity. Therefore the latter velocity may be used in a practical sense.     

应用地震道的F-LOG分析技术研究裂缝-孔隙性气藏

根据不同岩石对地震波不同频率分量衰减的差异,作者提出一种新的地震道分析技术,称为拟频率测井,用F-LOG表示。在地震道频谱分析的基础上,提取一个表征高频分量衰减程度(较低频分量而言)的参数,叫高衰指数。为了消除不相干因素的影响,计算中采用比值表示,故所得高衰指数只表示相对大小。 F-LOG是由地震道上每个样点值的高衰指数组成,它的相对高值表示对应的地层是岩石相对柔软、疏松或含油气情况。因此,利用这种F-LOG曲线有可能对储层的变化作出预测。文中讨论了F-LOG的层位标定、对比和提高分辨率的具体方法。采用本方法对四川盆地的乐平统生物礁的裂缝-孔隙性气藏;阳新统灰岩的裂缝-溶洞性气藏及中三叠统白云岩的裂缝-针孔性气藏开展了试验,获得了良好的效果。     

衍射光学束匀滑器件性能的空间频谱分析

采用空间频谱方法分析了衍射光学束匀滑器件的焦面光强分布 ,重新定义了光能利用率及顶部不均匀性两个参数 ,由于其定义的溯源性 ,能够真实准确地评价束匀滑器件的设计性能。最后 ,采用这两个参数对精细化设计前后的衍射光学束匀滑器件性能进行了对比 ,结果证明了精细化设计的有效性