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961.
Graded gate oxide process involves a two-step synthesis of growing an oxide at a temperature above the viscoelastic temperature (TVE ) onto a pregrown low temperature thermally grown SiO2 layer to form a composite graded SiO2 structure. The cooling rate is carefully modulated near TVE~925°C to enhance growth induced stress relaxation. The pregrown SiO2 layer provides grading and is a sink for stress accommodation for the final high temperature SiO2 forming the interface. Both grading and modulated cooling generate a strain-free and planar Si/SiO2 interface. Such an interface delivers significant enhancement in all aspects of device reliability and performance. These oxides are of very high-quality, robust, and manufacturable with a process capability index, Cpk>1.5. Graded gate oxide is already in the primary path of our 0.16 μm and 0.12 μm technologies 相似文献
962.
The effects of coincidence window and measuring volume size on two-component laser velocimeter measurement of turbulence
in an isothermal liquid flow through a concentric annular channel were studied. Three different coincidence windows (100–500 μs)
and three different measuring volume sizes (diameter, 5–9 wall units; spanwise length, 24–91 wall units) were used in a flow
of Reynolds number 31,500 and data density spanning the high end of intermediate to the low end of high (3–6). While no significant
effects of the coincidence window and measuring volume size were found on the time-mean velocity and turbulence intensities,
the streamwise Reynolds shear stress measured near a wall was found to be markedly affected by both. The smallest feasible
measuring volume along with an appropriate coincidence window provides good measurement of the shear stress.
Received: 8 September 1999/Accepted: 11 July 2000 相似文献
963.
Pinaki Roy 《Czechoslovak Journal of Physics》1984,34(6):516-519
Conclusion In the present article we have considered two supersymmetric non-abelian gauge theories in the presence of an external magnetic field. In has been shown that the effect of the magnetic field breaks suppersymmetry at the one-loop level; however, if supersymmetry is already broken spontaneously at the tree level, then the magnetic field effect does not restore it at the one-loop level. These facts could be used in SUSY GUT models (which are used to describe the early universe), to study phase transition in those models. 相似文献
964.
By studying the backward production data for meson resonances we investigate the dual properties of baryon-Reggeised antibaryon elastic scattering. We find strong support for the duality prediction that meson resonances in the baryon antibaryon channel should be dual to an exotic trajectory. 相似文献
965.
Conformationally rigid aromatic amino acids as potential building blocks for abiotic foldamers 总被引:1,自引:0,他引:1
Ramesh VV Roy A Vijayadas KN Kendhale AM Prabhakaran P Gonnade R Puranik VG Sanjayan GJ 《Organic & biomolecular chemistry》2011,9(2):367-369
This communication describes the development of conformationally constrained unnatural aromatic amino acids, constructed on rigid backbone wherein the carboxyl and amino groups project in two dimensions (planes) on the aromatic framework. Such a feature offers the possibility of design and development of conformationally ordered synthetic oligomers with intriguing structural architectures distinct from those classically observed. Furthermore, such amino acids will have the potential to extend the conformational space available for foldamer design with diverse backbone conformation and structural architectures. 相似文献
966.
967.
968.
We define the Lie algebrac(n) of centrosymmetric matrices. It generates a noncompact and nonsemisimple local Lie group with the unusual property that expc(n) c(n). The group contains an invariant subgroup of Lorentz boost/ dilation transformations. Forn even, these form a subgroup of the conformal group of the Lorentzian metric with signature (– + – + – +). 相似文献
969.
Abstract. The respiration rates and respiratory control ratios of isolated bean mitochondria have been measured following exposure to 0, 150, 300 and 900 J/m2 of far UV radiation (190–300 nm) from a mercury vapour light source with 90% total radiant intensity at 254 nm. Loss of respiratory control occurred at 150 J/m2 and inhibition of respiration was significant at the highest exposure dosage. The uptake of both 45 Ca and 85 Sr have been measured following a 10min incubation of isolated mitochondria with 2 m M cation. Significant decreases in cation accumulation were observed following exposure to 900 J/m2 . The effect seemed to be associated with loss of active transport of the ions as a result of respiratory uncoupling or reduced electron transport. There was no significant effect of storage on respiration or ion transport nor was there any indirect effect of irradiated suspending medium on mitochondria. 相似文献
970.
D.Roy Mahapatra 《Journal of sound and vibration》2003,268(3):429-463
A spectral finite element model (SFEM) for analysis of coupled broadband wave propagation in composite tubular structure is presented. Wave motions in terms of three translational and three rotational degrees of freedom at tube cross-section are considered based on first order shear flexible cylindrical bending, torsion and secondary warping. Solutions are obtained in wavenumber space by solving the coupled wave equation in 3-D. An efficient and fully automated computational strategy is developed to obtain the wavenumbers of coupled wave modes, spectral element shape function, strain-displacement matrix and the exact dynamic stiffness matrix. The formulation emphasizes on a compact matrix methodology to handle large-scale computational model of built-up network of such cylindrical waveguides. Thickness and frequency limits for application of the element is discussed. Performance of the element is compared with analytical solution based on membrane shell kinematics. A map of the distribution of vibrational modes in wavelength and time scales is presented. Effect of fiber angle on natural frequencies, phase and group dispersions are also discussed. Numerical simulations show the ease with which dynamic responses can be obtained efficiently. Parametric studies on a clamped-free graphite-epoxy composite tube under short-impulse load are carried out to obtain the effect of various composite configurations and tube geometries on the response. 相似文献