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排序方式: 共有104条查询结果,搜索用时 31 毫秒
51.
Ali A. Orouji S.E. Jamali Mahabadi P. Keshavarzi 《Superlattices and Microstructures》2011,50(5):449-460
In this paper for the first time, a partial silicon-on-insulator (PSOI) lateral double-diffused metal-oxide-semiconductor-field-effect-transistor (LDMOSFET) is proposed with a novel trench which improves breakdown voltage. The introduced trench in the partial buried oxide enhances peak of the electric field and is positioned in the drain side of the drift region to maximize breakdown voltage. We demonstrate that the electric field is modified by producing two additional electric field peaks, which decrease the common peaks near the drain and gate junctions in the trench-partial-silicon-on-insulator (T-PSOI) structure. Hence, a more uniform electric field is obtained. Two dimensional (2D) simulations show that the breakdown voltage of T-PSOI is nearly 64% higher in comparison with partial silicon on insulator (PSOI) structure and alleviate self heating effect approximately 9% and 15% in comparison with its conventional PSOI (C-PSOI) and conventional SOI (C-SOI) counterparts respectively. In addition the current of the T-PSOI, C-PSOI, conventional SOI (C-SOI), and fully depleted conventional SOI (FC-SOI) structures are 90, 82, 74, and 44 μA, respectively for a drain–source voltage VDS = 30 V and gate–source voltage VGS = 10 V. 相似文献
52.
The magnetic properties of tetragonal structure of stoichiometric NiMn alloy is investigated using density functional theory within the local spin density approximation. The system studied here, is a free standing film. The effect of thickness and epitaxial strain on the magnetic and structural properties is examined. It is found that while the magnetic moments of Mn surface atoms vary depending on the number of layers being odd (3.60 ) or even (3.55 ) the magnitude of the magnetic moment for surface Ni atoms is constant (0.11 ). By applying epitaxial strain on the slabs, it was observed, for the first time, that the magnetic phase of NiMn films changes from “A-type-like” ferrimagnetic for compressive strains to “G-type-like” ferrimagnetic for tensile strains. 相似文献
53.
Muhammad Rizwan Yasaman Ganjkhani Vahideh Farzam Rad Maasoomeh Bazzar Muhammad Yar Rosiyah Yahya Ali-Reza Moradi 《Surface and interface analysis : SIA》2020,52(4):132-139
In this paper, we show that laser speckle pattern provides useful information toward revealing discrimination between nanofibers and membranes. Chitosan materials particularly organosoluble chitosan derivatives have a number of applications. The surface characteristics of these materials are very critical for specific applications. The analysis of laser speckles, both numerical and graphical, includes information about the surface structure. The development of digital electronics brought the ease of image processing and has opened new perspectives for a spectrum of laser speckle analysis (LASCA) applications. Our results show reasonable differences between the LASCA parameters of nanofibers and membranes. The methodology may be considered as a quantitative assessment tool for similar samples. 相似文献
54.
Shahrajabian Hamzeh Bagherzadeh Seyed Amin Moghri Mehdi Karimi Vahid Jamali Mehdi 《Journal of Thermal Analysis and Calorimetry》2021,144(6):2099-2107
Journal of Thermal Analysis and Calorimetry - Doing experiments in order to determine mechanical properties of nanocomposites costs a lot. Therefore, finding the ways by which the properties of the... 相似文献
55.
A. Jamali 《Journal of Applied Mathematics and Computing》1998,5(2):351-359
In this paper we describe the results of computations to find symmetric presentations based on minimal conjugate generating pairs for the 32 non-abelian simple groups of order less than one million. 相似文献
56.
57.
A general method for the construction of trifluoromethylated 2‐quinolinones has been established herein by using a trifluoromethylative ring expansion of isatin with trifluorodiazoethane. The strategy provides a platform for the rapid synthesis of a wide range of substituted 3‐hydroxy‐4‐trifluoromethyl‐2‐quinolinones. This operationally simple and robust Ag‐catalyzed protocol successfully transforms isatin ketimines to 3‐amino‐4‐trifluoromethylquinolinones in excellent yields. The utility of this novel method is further illustrated by the conversion of the products into various synthetically and medicinally relevant molecules. 相似文献
58.
59.
G.R. Jahanshahloo F. Hosseinzadeh Lotfi N. Shoja A. Gholam Abri M. Fallah Jelodar Kamran Jamali Firouzabadi 《Mathematical and Computer Modelling》2011,53(5-6):587-596
One important issue in DEA which has been studied by many DEA researchers is the sensitivity of the results of an analysis to perturbations in the data.This paper develops a procedure for performing a sensitivity analysis of the inefficient decision making units (DMUs). The procedure yields an exact “Necessary Change Region” in which the efficiency score of a specific inefficient DMU changes to a defined efficiency score.In what follows, we identify a new frontier, and prove the efficiency score of each arbitrary unit on it which is defined as the efficiency score. 相似文献
60.
In this paper we give 2-generator 3-relation presentations for the simple groups PSU(3,5) of order 126000 and the Mathieu group M22Zof order 443520. We also give a 2-generator 2-relation presentation for the Janko group J1of order 175560. This proves that these three simple groups are efficient. 相似文献