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91.
G. Murali Dhar B. N. Srinivas M. S. Rana Manoj Kumar S. K. Maity 《Catalysis Today》2003,86(1-4):45-60
Support effects form important aspect of hydrodesulfurization (HDS) studies and mixed oxide supports received maximum attention in the last two decades. This review will focus attention on studies on mixed oxide supported Mo and W catalysts. For convenience of discussion, these are divided into Al2O3 containing mixed oxide supports, TiO2 containing mixed oxide supports, ZrO2 containing mixed oxide supports and other mixed oxide supports containing all the rest. TiO2 containing mixed oxides received maximum attention, especially TiO2–Al2O3 supported catalysts. A brief discussion about their prospects for application to ultradeep desulfurization is also included. An overview of the available literature with emphasis on research carried out in our laboratory form the contents of this publication. 相似文献
92.
Mathematical models of thermomechanical processes which are based on the laws of rational thermodynamics of irreversible processes are treated. Singular features of the unsteady-state behavior of a continuous medium are demonstrated within different models, such as a medium with internal parameters of state, a medium with memory, and a medium of the velocity type. 相似文献
93.
I. I. Abramov I. A. Goncharenko S. A. Ignatenko A. V. Korolev E. G. Novik A. I. Rogachev 《Russian Microelectronics》2003,32(2):97-104
The concept and structure of the NANODEV simulation software are described. NANODEV deals with nanoelectronic devices that exploit single-electron tunneling, resonant tunneling, or quantum interference. It can use both simplified and sophisticated models and enables one to evaluate a wide variety of devices and configurations. The capabilities of NANODEV are illustrated by examples. 相似文献
94.
Can digital rights management be standardized? 总被引:1,自引:0,他引:1
With increasing use of the Internet as a content-distribution platform, mere interoperability of the codec is no longer sufficient if content owners are not prepared to distribute their content online for fear of piracy. Therefore, one also needs interoperability in the area of managing and protecting related intellectual property rights. To provide interoperability of digital rights management (DRM) systems to protect the content rather than the distribution channel, MPEG has embarked on developing intellectual property management and protection (IPMP) specifications targeted at the content itself that are natively built into its standards. It is the hope that such standards will allow for interoperability of content commerce systems, giving consumers more choice, while providing rights holders with the tools to effectively protect their assets and to develop complex and attractive business offering to tempt consumers. While it remains uncertain whether standardization is in fact the right vehicle to provide the e-content market with an impetus to grow, it appears that MPEG is working on a set of specifications with relatively good chances of helping to achieve this goal. 相似文献
95.
Passaro V.M.N. Armenise M.N. Nesheva D. Savatinova I.T. Pun E.Y.B. 《Lightwave Technology, Journal of》2002,20(1):71-77
Proton-exchanged planar waveguides have been fabricated on Z-cut and X-cut lithium niobate crystals by using a new proton source formed by a mixture of benzoic and adipic acids. Waveguide index profiles and optical characteristics have been obtained at different values of the adipic-benzoic acid concentration ratio. The samples have been structurally characterized by Raman and infrared (IR) absorption spectroscopy and double-crystal X-ray diffraction. Good quality samples have been fabricated by using 30 mol% ratio dilution, showing very low scattering levels (<0.1 dB/cm), relatively high electrooptic coefficient (r33=0.88 pm/V), and low relative percentage of interstitial protons (26%). The main factor limiting the waveguide optical properties is the substitutional-interstitial proton ratio, which can be easily controlled to produce good quality waveguides. A demonstration of the repeatability of the exchange process in the acid mixture is also provided 相似文献
96.
97.
Martinez-Munoz D. Rosa-Zurera M. Cruz-Roldan F. Lopez-Ferreras F. Ruiz-Reyes N. 《Electronics letters》2002,38(16):932-933
The problem of computing, in a subband audio coder, the maximum quantisation noise power that can be injected in each band to ensure transparent coding when low selectivity filter banks are used, is addressed. A low complexity strategy, taking into account the frequency responses of the synthesis filter bank, is proposed for achieving an overall distortion due to quantisation noise always below the masking threshold (provided by a psycho-acoustic model) for any length prototype filters. 相似文献
98.
Mine K. Kubota N. Morimoto F. Sanada M. Zhang Qi 《Electromagnetic Compatibility, IEEE Transactions on》1994,36(3):253-255
This short paper discusses the method of effectively canceling equal status normal mode noise not only on a sensor line but also on a transmission line of an optical instrument using a sensor with a sensordummy resistance 相似文献
99.
Younan N.H. Cox B.I. Taylor C.D. Prather W.D. 《Electromagnetic Compatibility, IEEE Transactions on》1994,36(4):394-398
Efficient numerical solution techniques have been developed and used to examine the electromagnetic fields that can be developed in the working volume of the CW Ellipticus antenna operated at frequencies from 100 kHz to 1 GHz. An exponentially tapered transition section is designed to obtain the desired illumination pattern in the working volume. The input transition section is needed for impedance matching and to drive efficiently the Ellipticus antenna. A parametric study is performed to ascertain the performance of the Ellipticus antenna for frequencies up to 1 GHz 相似文献
100.
1/f noise sources 总被引:2,自引:0,他引:2
This survey deals with 1/f noise in homogeneous semiconductor samples. A distinction is made between mobility noise and number noise. It is shown that there always is mobility noise with an α value with a magnitude in the order of 10-4. Damaging the crystal has a strong influence on α, α may increase by orders of magnitude. Some theoretical models are briefly discussed none of them can explain all experimental results. The α values of several semiconductors are given. These values can be used in calculations of 1/f noise in devices 相似文献