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81.
Due to challenges with relentless scaling of conventional bulk complementary metal-oxide- semiconductor (CMOS) devices, non-conventional CMOS devices have been of great interest to scale metaboxide-semiconductor field effect transistors (MOSFETs) to the 32nm gate length and below effectively. Among non-conventional CMOS devices, quadruple-gate (QG) MOSFETs have been gaining interest because they are sup- posed to provide excellent electrostatic controllability for ultra-large-scale integration (ULSI) applications. A number of attempts have been made to analyze QG MOSFETs analytically with a great amount of success. Sharma et al. have presented an an- alytical threshold voltage model for QG MOSFETs using an isomorphic polynomial function for solv- ing the 3D Poisson equation. Chiang has presented a number of models of scaling length,threshold voltage and subthreshold current for QG MOS- FETs adopting a concept of the so-called equivalent number of gates (ENGs). 相似文献
82.
An all-fiber optical laser pulse multi-pass stretcher using a chirped fiber Bragg grating (CFBG) is demonstrated. Pulses from a 1 053-nm mode-locked fiber seed oscillator are stretched by multiple passing through a chirped fiber grating set in a fiber regenerative amplifier structure. We stretch the pulse from 16 ps to 1.855 ns after it transmits seven loops in the stretcher. The main factors that affect the stretching results are discussed. 相似文献
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N.V. Rama Rao R. Gopalan M. Manivel Raja V. Chandrasekaran D. Chakravarty R. Sundaresan R. Ranganathan K. Hono 《Journal of magnetism and magnetic materials》2007
SmCo5+x wt% Fe (x=0, 5 and 10) nanocomposite powders were synthesized by mechanical milling and were consolidated into bulk shape by spark plasma sintering (SPS) technique. The evolution of structure and magnetic properties were systematically investigated in milled powders as well as in SPS samples. A maximum coercivity of 8.9 kOe was achieved in spark plasma sintered SmCo5+5 wt% Fe sample. The exchange spring interaction between the hard and soft magnetic phases was evaluated using δM–H measurements and the analysis revealed that the SPS sample containing 5 wt% Fe had a stronger exchange coupling between the magnetic phases than that of the sample with10 wt% Fe. 相似文献
86.
Nirmal Kumar Sarkar Joydeep Choudhury Srinivasa Rao Karumuri Ramendu Bhattacharjee 《Molecular physics》2013,111(5):693-702
Using the Lie algebraic method the vibrational energy levels of HCCF and HCCD are calculated for 102 and 110 vibrational bands, respectively, using the local Hamiltonian. A comparative study is made between the two. Better results are obtained than those published earlier from local mode analysis. 相似文献
87.
Abstract ESR spectra of γ-irradiated frozen aqueous solutions of a number of organic compounds such as alcohols, ether, acetone and tetrahydrofurans have been examined in the presence and absence of mineral acids such as H2SO4. The presence of the acid is found to cause an intensification of the organic radical ESR spectra as compared with the acid free solutions. Also, the presence of the organic compounds in frozen aqueous H2SO4 suppresses the formation of both H-atoms and SO4 ? radical ions. These results have been explained on the basis of reactions of the electrons and holes, or excitons, primarily formed by the action of radiation on the substrate ice. 相似文献
88.
Abstract In this study, the molecular weights of the polymer from vinyl benzoate has been reported for different dose rates and different temperatures. The mol.wt. remains around 4000. With increasing dose, the molecular weight increases to about 14,000. The degrees of polymerization and the kinetic chain lengths calculated from the experimentally determined G R values have been compared which show that the kinetic chain length is larger than the D ? Pn. From a plot of the (D ? Pn)?1 vs. R p , an intercept is obtained which is equal to 3.25 × 10?2 which is higher than obtained in conventional polymerization. By examining the effect of temperature on mol.wt., the dependence of R p on dose rate and the absence of induction period it has been concluded that chain transfer occurs to impurities that are generated during radiolysis. 相似文献
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