A method of estimating the standard gibbs free energy of formation

Standard Gibbs free energy of formation (ΔG_f⁰), an important property needed in design calculations has been estimated using molar refraction, R_M. The linear relationships derived between ΔG_f⁰ and R_M tested with the data on 8 series of hydrocarbons at 228 compounds yielded average deviations comparable to the methods cited in recent literature. The method can be used as an alternative to the existing ones, because of its simplicity combined with reasonable accuracy.     

无间隙原子钢的微观结构特征和塑性应变比

采用Ｘ射线衍射的ＯＤＦ和ＬＰ分析技术，ＳＥＭ电子通道花样和蚀坑技术观测，研究了超深冲无间隙原子钢板的微观结构特征。结果表明：控制化学成分、保证基体纯净、优选工艺参数，促进强的γ－〈１１１〉∥Ｎ．Ｄ纤维织构的形成是获得优异成型性的关键。用ＣＭＴＰ方法，由ＯＤＦ织构数据从理论计算了塑性应变比（ｒ），表明ｒｍ值高达３．１８。文中讨论了再结晶织构形成机制。     

ATM技术在校园网中的实时性应用

讨论了ＡＴＭ论坛关于局域网仿真技术的基本思想及其协议体系的工作过程，并介绍了利用局域网仿真技术在校园网中应用ＡＴＭ技术实现视频传输的方法。     

Multiresolution coding techniques for digital television: A review

Multiresolution decompositions for video coding are reviewed. Both nonrecursive and recursive coding schemes are considered. In nonrecursive schemes, it is shown that pyramid structures have certain advantages over subband or wavelet techniques, and a specific spatiotemporal pyramid coding of HDTV is discussed in some detail. It is shown that recursive, DPCM like schemes will incur a slight loss of optimality due to a restricted form of prediction if multiresolution decomposition with compatible decoding is required. Compatibility and transmission issues are also discussed. Multiresolution transmission for digital broadcast TV is introduced. This, when combined with multiresolution source coding, achieves spectrum efficiency, robustness and graceful degradation under channel impairments.Invited PaperWork supported in part by the National Science Foundation under grants ECD-88-11111, MIP-90-14189 and Bell Communications Research.Work supported by the National Science Foundation under grants ECD-88-11111. K.M. Uz is now with David Sarnoff Research Center in Princeton, NJ 08543.     

Improvement of the methods of reproducing and transferring the dimensions of the unit of sound pressure in an aqueous medium under free-field conditions

Methods of reducing the predominant components of uncertainty in standards of sound pressure in an aqueous medium in a free field, and also methods of increasing the accuracy when the dimensions of the unit of a physical quantity are transferred by the means employed in natural measurements are reviewed. __________ Translated from Izmeritel’naya Tekhnika, No. 8, pp. 59–63, August, 2007.     

超越离合器内星轮对数螺旋楔合面的设计

通过对采用平面楔合面内星轮的超越离合器的受力及磨损对其使用可靠性影响的分析，从而提出了用对数螺旋楔合而代替平面楔合面的设计方案，并对两种方案进行了比较。     

Activity measurement of the constituents in molten Fe–B and Fe–B–C alloys

The distribution ratios of Fe and B between molten Fe–B alloy and molten Ag were measured at temperatures between 1573 and 1923 K. Also, distribution ratios of Fe and B between molten Fe–B–C_satd. alloys and molten Ag were measured at 1873 K. It was found that the excess Gibbs free energy of mixing in molten Fe–B and Fe–B–C alloys can be expressed by utilizing the Redlich–Kister polynomial. The activity curves of the elements in molten Fe–B alloy and Fe–B–C alloy were estimated.     

Silver electrodeposition from air and water-stable ionic liquid: An environmentally friendly alternative to cyanide baths

The influence of temperature on the kinetics and the morphology of silver deposits obtained from an air and water-stable ionic liquid (the 1-butyl-3-methyl imidazolium tetrafluoroborate) was studied by means of cyclic voltammetry and chronoamperometry. The nucleation and growth mechanisms have been investigated and the effect of temperature evaluated up to 200 °C. Dense, pure and very thin (about 0.3 μm) silver coatings, with decorative properties, have been obtained on commercial copper electrodes at different temperatures. The characterization of the deposits morphology has been performed by visual investigation and SEM microscopy. Data about thickness were acquired by Calotest® measurements. The deposits result constituted by pure silver as determined by combination of EDX microanalysis and Auger Electron Spectroscopy (AES). The deposition method promises to be a new, environmentally friendly, method for silver electrodeposition which is the reason for the absence of cyanide and volatile toxic solvents in the electroplating bath.     

微重力落塔电磁悬吊、释放技术研究

论述了微重力落塔电磁悬吊、释放、提升机构的关键技术,电磁释放过程的特性分析以及微重力落塔实际试验的情况。分析说明:悬吊、释放性能的好坏决定了试验落舱的微重力水平,也是微重力落塔试验能否成功的关键技术。     

一种视频信号压缩编码方法的研究

文章采用自适应预测编码加熵编码的复合编码方法，对视频信号进行压缩编码。计算机模拟结果表明，压缩比为3.5：1（2.25bits／Pixel）时可获得良好的图像质量，因此，可实现在PCM三次群信道上传输一路彩色电视信号。