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991.
Wei Jin Chan P.C.H. Fung S.K.H. Ko P.K. 《Electron Devices, IEEE Transactions on》1999,46(6):1180-1185
Floating-body partially depleted (PD) SOI MOSFET's exhibit excess low-frequency noise. For the first time, the origin of the excess noise is identified to be the shot noise associated with impact ionization current and body-source diode current. The shot noise, normally negligible as compared with flicker noise, is amplified in the device through the floating-body effect (FEE). A physically-based noise model is proposed which predicts that the excess low-frequency noise shows a Lorentzian-like spectrum as verified by experimental data. The physical explanation is further supported by the coincidence of the characteristic frequency in noise spectrum and AC output impedance of the device 相似文献
992.
对用电子能量为1.7,0.5和0.4MeV的电子辐照和中子辐照后的n型6H-SiC样品进行低温光致发光研究.对于Ee≥0.5MeV电子辐照和中子辐照后的样品,首次发现了位于478.6/483.3/486.1n m的S1/S2/S3谱线.对样品进行热退火研究表明S1/S2/S3谱线在500℃下消失,而退火温度高于700℃时D1中心出现.考虑到产生C空位和Si空位所需的位移阈能以及热退火行为,说明S1/S2/S3为初级Si空位初级缺陷,而D1中心为二次缺陷. 相似文献
993.
994.
Shao Yong Zheng Sai Ho Yeung Wing Shing Chan Kim Fung Man Shu Hung Leung 《Microwave Theory and Techniques》2009,57(1):180-188
This paper presents, for the first time, the design of a size-reduced rectangular patch hybrid coupler. Different types of compact rectangular patch hybrid couplers with different ground plane patterns are described. For demonstration, two compact rectangular patch hybrid couplers are designed to operate at 3.5 GHz. They are measured to have 30.1% and 33.3% bandwidth with 67.3% and 72.3% size reduction compared with the optimized one without patterned ground plane. 相似文献
995.
Mei X.B. Yoshida W. Deal W.R. Liu P.H. Lee J. Uyeda J. Dang L. Wang J. Liu W. Li D. Barsky M. Kim Y.M. Lange M. Chin T.P. Radisic V. Gaier T. Fung A. Samoska L. Lai R. 《Electron Device Letters, IEEE》2007,28(6):470-472
rdquoWe report the first submillimeter-wave monolithic microwave integrated circuit (MMIC) amplifier with 4.4-dB measured gain at 308-GHz frequency, making it the highest frequency MMIC amplifier reported to date. In this letter, a 35-nm InP high-electron mobility transistor process has been successfully developed with a projected maximum available gain of greater than 7 dB at 300 GHz. The excellent dc and RF performance makes it suitable for applications at frequencies well into the millimeter-wave band and, for the first time, in the submillimeter- wave band as well. 相似文献
996.
997.
Mariano Venanzi Prof. Gianfranco Bocchinfuso Dr. Emanuela Gatto Dr. Antonio Palleschi Prof. Lorenzo Stella Prof. Fernando Formaggio Prof. Claudio Toniolo Prof. 《Chembiochem : a European journal of chemical biology》2009,10(1):91-97
The metal ion binding properties of two fluorescent analogues of trichogin GA IV, which is a natural undecapeptide showing significant antimicrobial activity, were studied by circular dichroism, time‐resolved optical spectroscopy, and molecular mechanics calculations. Binding of CaII and GdIII to the peptides investigated was shown to promote a structural transition from highly helical conformations to folded structures characterized by formation of a loop that embedded the metal ion. Time‐resolved spectroscopy revealed that peptide dynamics is also remarkably affected by ion binding: peptide‐backbone motions slowed down to the microsecond time scale. Finally, molecular mechanics calculations emphasized the role of the central Gly5‐Gly6 motif, which allowed for the twisting of the peptide segment that gave rise to the formation of the binding cavity. 相似文献
998.
Noelia Flores Marco Jorge Silva Colomer Renée Alicia Anschau Stella Carballo Jorge Antonio Hilbert 《International Journal of Hydrogen Energy》2010
In this work, the partial results of the potential production of energy, starting from the biomass and the development of the crops, directed to the production of bio-fuels (Colza and Topinamur) in the North irrigation oasis of Mendoza, Argentina within the National Program of Bio-energy developed by INTA is presented. 相似文献
999.
Samoska L. Deal W.R. Chattopadhyay G. Pukala D. Fung A. Gaier T. Soria M. Radisic V. Mei X. Lai R. 《Microwave Theory and Techniques》2008,56(6):1380-1388
In this paper, we report on the first demonstration of monolithically integrated waveguide transitions in a submillimeter-wave monolithic integrated circuit (S-MMIC) amplifier module. We designed the module for a targeted frequency range of 300-350 GHz, using WR2.2 for the input and output waveguides. The waveguide module utilizes radial -plane transitions from S-MMIC to waveguide. We designed back-to-back radial probe transitions separated by thru transmission lines to characterize the module, and have incorporated the radial -plane transitions with an S-MMIC amplifier, fabricated monolithically as a single chip. The chip makes use of an S-MMIC process and amplifier design from the Northrop Grumman Corporation, Redondo Beach, CA, using 35-nm gate-length InP transistors. The integrated module design eliminates the need for wire bonds in the RF signal path, and enables a drop-in approach for minimal assembly. The waveguide module includes a channel design, which optimizes the -plane probe bandwidth to compensate for an S-MMIC width, which is larger than the waveguide dimension, and is compatible with S-MMIC fabrication and design rules. This paper demonstrates for the first time that waveguide-based S-MMIC amplifier modules with integrated waveguide transitions can be successfully operated at submillimeter-wave frequencies. 相似文献
1000.
A comprehensive reactor analysis package is provided that will enable more accurate comparison of catalyst activity in various reactor types and reaction conditions. Conservation of mass was applied to formulate the performance equations for catalytic batch, plug flow, continuous stirred tank, and pulse reactors. The weight hourly space velocity was correlated with the conversion and the reaction rate in many integral forms. The apparent reaction rate constant can be obtained from kinetic data for each reactor type. 相似文献