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61.
William E Acree Jr Michael H Abraham 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2006,81(8):1441-1446
The contentions made in an earlier paper [J Chem Technol Biotechnol 80 : 133–137 (2005)] that the coefficients of the Abraham solvation equation do not provide meaningful information on the molecular properties of ionic liquid solvents is refuted. The objections noted in the earlier paper disappear when the solvation equation model is correctly applied to the experimental data. It is further shown that the coefficients of the Abraham solvation equations can be used to characterize ionic liquids and can be used to select solvents for the solubility of gaseous solutes. Copyright © 2006 Society of Chemical Industry 相似文献
62.
A Review of Wavelets for Digital Wireless Communication 总被引:2,自引:1,他引:1
Wavelets have been favorably applied in almost all aspects of digital wireless communication systems including data compression, source and channel coding, signal denoising, channel modeling and design of transceivers. The main property of wavelets in these applications is in their flexibility and ability to characterize signals accurately. In this paper recent trends and developments in the use of wavelets in wireless communications are reviewed. Major applications of wavelets in wireless channel modeling, interference mitigation, denoising, OFDM modulation, multiple access, Ultra Wideband communications, cognitive radio and wireless networks are surveyed. The confluence of information and communication technologies and the possibility of ubiquitous connectivity have posed a challenge to developing technologies and architectures capable of handling large volumes of data under severe resource constraints such as power and bandwidth. Wavelets are uniquely qualified to address this challenge. The flexibility and adaptation provided by wavelets have made wavelet technology a strong candidate for future wireless communication.
Madan Kumar Lakshmanan was born in Chennai, India, in 1979. He received the B.E. (with distinction) in electrical engineering from the University of Madras, Chennai, India, in 2000. He joined the Indian Software firm, Polaris Software Labs Ltd., in 2000 where he wrote software for Telecommunication applications. At Polaris, he was awarded the “On The Spot Of Excellence Award” for his efforts. In 2003, he moved to the Indian Institute of Technology-Madras, to develop and establish a wireless communications network for rural connectivity. In 2004, he was awarded the Royal Dutch/Shell Chevning scholarship to pursue a Master degree in Telecommunications at the Delft University of Technology (TUDelft). At TUDelft he is affiliated to the International Research Center for Telecommunications-Transmission and Radar (IRCTR) where he is undertaking research in the field of wavelets applications in Wireless Communications.
Homayoun Nikookar received his Ph.D. in Electrical Engineering from Delft University of Technology (TUDelft), The Netherlands, in 1995. From 1995 to 1998 he was a postdoc researcher at the International Research Center for Telecommunications-Transmission and Radar, TUDelft, where since 1999 he has been an Assistant Professor. Dr. Nikookar has done research on different areas of wireless communications, including wireless channel modeling, UWB, MIMO, multicarrier transmission, Wavelet-based OFDM and CDMA. He is a senior member of the IEEE. 相似文献
63.
This research was an investigation of children's performance on a task that requires memory binding. In Experiments 1 and 2, 4-year-olds, 6-year-olds, and adults viewed complex pictures and were tested on memory for isolated parts in the pictures and on the part combinations (combination condition). The results suggested improvement in memory for the combinations between the ages of 4 and 6 years but not in memory for the isolated parts. In Experiments 2 and 3, the authors also examined the developmental relationship between performance in the combination condition and free recall of a naturalistic event, finding preliminary evidence that performance on a memory task that requires binding is positively related to performance in episodic memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
64.
ABSTRACT: The thermal evolution behavior of the organic free radicals induced in irradiated black pepper was studied by electron spin resonance spectroscopy. To analyze the time-dependent evolution process, we used the theory of transient phenomena, that is, an ordinal differential equation, as well as the nonlinear least squares numerical method. We found that the radical evolution that occurred in the irradiated pepper obeys a single exponential function and yields a unique time constant. The evolution of the organic free radical undergoes a simple reaction process of a single radical species. 相似文献
65.
66.
针对显色剂-过渡金属元素-过氧化氢体系,用分光光度法间接测定羟自由基。通过大量试验,确定了三苯甲烷类酸性酚醌吡喃类为有效显色剂,并确定了溴邻苯三酚红-亚铁离子-过氧化氢体系测定羟自由基的最佳条件,首次推测出其最可能的反应机理为:亚铁离子催化过氧化氢产生羟自由基,羟自由基氧化溴邻苯三酚红上的羰基碳氧双键,破坏其显色的共轭结构,使其褪色,此法可作为筛选羟自由基清除剂的有效方法。 相似文献
67.
F. R. Perioto M. E. T. Alvarez W. A. Araujo M. R. Wolf‐Maciel R. Maciel Filho 《应用聚合物科学杂志》2008,110(6):3544-3551
A new calculation procedure for free‐volume parameters is considered in this work by using viscosity prediction methods and the Levenberg‐Marquardt calculation scheme. All parameters used in the Vrentas–Duda free‐volume theory can be estimated from pure component properties. The prediction results are compared with experimental data for some polymer/solvent systems. The diffusion coefficient calculated by Vrentas–Duda theory can be used in the modeling of membrane separation processes. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
68.
69.
This paper deals with the thermal analysis of carbon nanotube (CNT) based composites by meshless element free Galerkin method.
Cylindrical representative volume element (cylindrical RVE) has been chosen to evaluate the thermal properties of nano-composites
using multi-domain and simplified approaches. The values of temperature have been calculated at different points and plotted
against RVE length and RVE radius. A sensitivity analysis of RVE as well as CNT dimensions has been carried out in detail.
The present computations show that the equivalent thermal conductivity is a function of CNT length, CNT radius, RVE length
and RVE radius. Based on present numerical simulations, an approximate formula is proposed to calculate the equivalent thermal
conductivity of nano-composites. The results obtained by simplified approach have been found in good agreement with those
obtained by multi-domain approach. 相似文献
70.
为了解决上游围堰防渗及绕坝渗漏问题,确定最优防渗方案,对炳灵水电站右岸松动体防渗帷幕的防渗方案进行了三维有限元渗流计算,并对右岸松动体帷幕的防渗范围和灌浆排数进行了敏感性分析。通过多种防渗方案的计算,对右岸松动体的防渗方案做了相应优化,建议了满足设计要求的防渗方案。 相似文献