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91.
Journal of Materials Science: Materials in Electronics - Natural muscovite (nM) exhibiting magnetic vortex states are ball milled into fine powder and mixed in different relative ratios (weight %)...  相似文献   
92.
In this paper, analytical model for threshold voltage is derived for fully depleted Triple material Surrounding gate (TMSG) SOI MOSFET. Three gate material of different work functions are introduced in the SOI MOSFET structure to reduce the short channel effects. The two dimensional Poisson equation is solved and based on parabolic approximation method, the model for threshold voltage is developed. The threshold voltage is analyzed for device parameters such as gate length ratios, oxide thickness, silicon thickness, doping concentration. The results of the analytical model values are validated using MEDICI simulation.  相似文献   
93.
The ability of Campylobacter jejuni ATCC 11168 to survive on beef and pork stored under chilled, vacuum packaged and retail display conditions were examined. In addition, the effect of natural microflora on commercial beef and pork on the survival of C. jejuni under these storage conditions was examined. When sterile cores of beef and pork were inoculated with ∼105 to 106 cfu cm−2C. jejuni, and were stored under aerobic or vacuum packaged conditions at −1.5 or 4 °C, its numbers dropped significantly and C. jejuni could not be enumerated by direct plating after 21 d of the 6 wks study. In contrast, survival of C. jejuni on commercial vacuum packaged beef and pork was significantly enhanced, resulting in only 1 log cfu cm−2 reduction at the end of 6 wks. During 7 d of display in a retail case, numbers of C. jejuni dropped quickly, but could be enumerated by direct plating even after the 7 d. The presence of high numbers of inoculated C. jejuni on beef and pork had no significant effect on the natural microflora numbers compared to uninoculated controls when the meat was stored either in vacuum or in a retail display case. These results show that natural microflora on vacuum packaged meat afford enhanced survival of C. jejuni present on the surfaces of both beef and pork when stored at refrigeration temperatures. Hence, strict hygienic practices or the implementation of decontamination technologies are recommended to ensure safety of meat with respect to this pathogen.  相似文献   
94.
95.
Describes a 256-word × 32-bit 4-read, 4-write ported register file for 6-GHz operation in 1.2-V 130-nm technology. The local bitline uses a pseudostatic technique for aggressive bitline active leakage reduction/tolerance to enable 16 bitcells/bitline, low-Vt usage, and 50% keeper downsizing. Gate-source underdrive of -V cc on read-select transistors is established without additional supply/bias voltages or gate-oxide overstress. 8% faster read performance and 36% higher dc noise robustness is achieved compared to dual-Vt bitline scheme optimized for high performance. Device-level measurements in the 130-nm technology show 703× bitline active leakage reduction, enabling continued Vt scaling and robust bitline scalability beyond 130-nm generation. Sustained performance and robustness benefit of the pseudostatic technique against conventional dynamic bitline with keeper-upsizing is also presented  相似文献   
96.
Polypropylene–maleic anhydride (PP–MA) graft copolymers were produced from isotactic homopolymer polypropylene (molecular weight > 150,000) utilizing the technique of solid phase graft copolymerization. A high degree of graft (about 8–10%) was achieved on 150 mesh (U.S. Standard Sieve) samples using this process. This free-radical-initiated, catalyst-aided grafting process was effective at low temperatures (100–120°C), atmospheric pressure, and low residence times (60 min). The powder was mixed in a low shear, fixed speed, continuous mixer where the ingredients were added in stages to effect the reaction. The interfacial agent was used to etch the polymer to provide sites for the reaction. The powder was removed from the reactor on completion of the reaction. This process can be further applied to graft other reactive monomers on polypropylene (PP).  相似文献   
97.
An overview of the theory, properties, and potential applications of compound slots is given. Methods for analyzing compound slots are discussed. Scattering properties of the compound slot are examined, covering resonance and the equivalent circuit model, resonant length scattering in the main waveguide, the aperture electric field, and off-resonant characteristics. Array characteristics are also considered, including external mutual coupling, internal higher order mode coupling, and some factors to consider in designing array configurations. Problems remaining to be solved are indicated  相似文献   
98.
This paper presents a powerful method for analysing antennas which can be considered principally two-dimensional (2-D) or cylindrical, except for some three-dimensional (3-D) physical or equivalent sources, e.g., dipoles or slots. It is shown by Fourier transform techniques that such antennas can be analyzed as 2-D problems with harmonic longitudinal field variation. The radiation pattern can often be determined directly from a finite set of such 2-D solutions, each one obtained by any method, e.g., the moment method. The mutual interaction between the cylindrical scatterer and the sources must be calculated to determine the exact current distribution on the sources and their impedances or admittances. This is facilitated by performing an inverse Fourier transform of an infinite spectrum of the numerical 2-D solutions followed by a moment method solution in the spatial domain to satisfy the boundary conditions on the 3-D equivalent sources themselves. The inverse Fourier transform is simplified by the use of asymptote extraction. The method is in itself a hybrid technique as one method is used to solve the harmonic 2-D problem, and the other to solve for the source currents  相似文献   
99.
The singular nature of the UTD (uniform geometrical theory of diffraction) subreflector scattered field at the vicinity of the main reflector edge (for a high-grain antenna design) is investigated. It is shown that the singularity in the UTD edge-diffracted and slope-diffracted fields is due to the reflection distance parameter approaching infinity in the transition functions. While the GO (geometrical optics) and UTD edge-diffracted fields exhibit singularities of the same order, the edge slope-diffracted field singularity is more significant and is substantial for greater subreflector edge tapers. The diffraction analysis of such a subreflector in the vicinity of the main reflector edge has been carried out efficiently and accurately by a stationary phase evaluation of the φ-integral, whereas the &thetas;-integral is carried out numerically. Computational results from UTD and PO (physical optics) analysis of a 34-m ground station dual-shaped reflector confirm the analytical formulations for both circularly symmetric and offset asymmetric subreflectors. It is concluded that the proposed PO&thetas;GOφ technique can be used to study the spillover or noise temperature characteristics of a high-grain reflector antenna efficiently and accurately  相似文献   
100.
This letter reports on 1.5-V single work-function W/WN/n/sup +/-poly gate CMOS transistors for high-performance stand-alone dynamic random access memory (DRAM) and low-cost low-leakage embedded DRAM applications. At V/sub dd/ Of 1.5-V and 25/spl deg/C, drive currents of 634 /spl mu/A//spl mu/m for 90-nm L/sub gate/ NMOS and 208 /spl mu/A-/spl mu/m for 110-nm L/sub gate/ buried-channel PMOS are achieved at 25 pA//spl mu/m off-state leakage. Device performance of this single work function technology is comparable to published low leakage 1.5-V dual work-function technologies and 25% better than previously reported 1.8-V single work-function technology. Data illustrating hot-carrier immunity of these devices under high electric fields is also presented. Scalability of single work-function CMOS device design for the 90-nm DRAM generation is demonstrated.  相似文献   
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