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1.
Journal of Computational Electronics - Power-delay-product optimal design of repeater size and number design for both horizontal and vertical multilayer graphene nanoribbon (MLGNR) interconnects is... 相似文献
2.
The AISI 420 martensitic stainless steel was surface-hardened by a pulsed Nd:YAG laser. The influences of process parameters (laser pulse energy, duration time and travel speed) on the depth and hardness of laser treated area and its corrosion behavior were Investigated. In the optimum process parameters, maximum hardness (490 VHN) in the laser surface treated area was achieved. The pitting corrosion behavior was studied by potentiodynamic polarization technique in 3.5% NaCl solution at 25 °C. Metallographical and electrochemical corrosion studies illustrated beneficial effects of laser surface hardening by refining the microstructure and enhancing the pitting corrosion resistance of the martensitic stainless steel. The pitting corrosion resistance of laser surface treated samples in 3.5% NaCl solution depends on the overlap ratio clearly. The pitting potential (Epp) decreased significantly by increasing the ratio of pulse overlapping. 相似文献
3.
Mohammadreza Mahmoudi Sungjin Kim Arif M. Arifuzzaman Tomonori Saito Corson L. Cramer Majid Minary-Jolandan 《International Journal of Applied Ceramic Technology》2022,19(2):939-948
Preceramic polymer resins are attractive for the 3D printing of net-shaped ceramic components. Recently various processes have been demonstrated for 3D printing of polymer-derived ceramics (PDCs). Ultimately in these processes, the process outcomes strongly depend on the process parameters. In particular, for PDCs the ceramic density, and ceramic yield are affected by the catalyst concentration and cross-linking duration. Here, we use thermal analysis and FTIR to quantify the interrelation of the process parameters on the process outcome for polysilazanes and demonstrate 3D printing of PDC components based on the best-identified process parameters. The results of this work can be used as guidelines for future additive manufacturing of PDCs. 相似文献
4.
Mina Shahi Amir Houshang Mahmoudi Farhad Talebi 《International Communications in Heat and Mass Transfer》2010
In this paper, 3-dimensional numerical simulation of steady natural convective flow and heat transfer are studied in a single-ended tube with non-uniform heat input. Apart from some other applications, it serves as a simplified model of the single-ended evacuated solar tube of a water-in-glass evacuated tube solar water heater. It is assumed that the sealed end of tube to be adiabatic and also the tube opening to be subjected to copper–water nanofluid. Governing equations are derived based on the conceptual model in the cylindrical coordinate system. The governing equations have been then approximated by means of a fully implicit finite volume control method (FVM), using SIMPLE algorithm on the collocated arrangement. The study has been carried out for solid volume fraction 0 ≤ φ ≤ 0.05 and maximum heat flux 100 ≤ qm ≤ 700. Considering that the driven flow in the tube is influenced by the dimensions and the inclination angle of the solar tube, the flow patterns and temperature distributions are presented on different cross sectional planes and longitudinal sections, when the tube is positioned at different orientations. 相似文献
5.
Hadadian Nejad Yousefi Hossein Seifi Kavian Yousef Mahmoudi Alimorad 《浙江大学学报:C卷英文版》2019,20(9):1266-1276
Frontiers of Information Technology & Electronic Engineering - Rapid developments in information and communication technology in recent years have posed a significant challenge in wireless... 相似文献
6.
7.
The single-photon strong coupling in the deep-resolved sideband of the optomechanical system induces photon blockade (PB) effect. For the PB cavity, an initial mechanical coherent state evolves into superposition of phonon cat states entangled with the cavity Fock states. Measurement of the cavity photon number states produces phonon even and odd cat states. The information leakage effect of two photon states on the fidelity of cat states is calculated, it is shown that for low average phonon number this effect is negligible and decreases by increasing the two photon cavity state. The Lindblad equation is solved numerically to obtain the environmental effects on the fidelity of cat states. 相似文献
8.
One of the major problems associated with HCCI combustion engine application is lack of direct control for combustion timing. A proposed solution for combustion timing control is using a binary fuel blend in which two fuels with different auto-ignition characteristics are blended at various ratios on a cycle-by-cycle basis.The aim of this research is to investigate the exergy analysis of HCCI combustion when a blended fuel, which consists of n-heptane and natural gas, is used. In order to accomplish this task, a single-zone combustion model has been developed, which performs combustion computations using a complete chemical kinetics mechanism.The study was carried out with different percentages of natural gas in blended fuels and EGR (exhaust gas recirculation) ranging from about 45 to 85 percent and 0 to 40 percent, respectively. The results reveal that, when mass percentage of natural gas increases, exergy destruction is decreased increasing the second-law efficiency. Introducing EGR into the intake charge of dual fuel HCCI engine up to some stage (optimum value) enhances the second-law performance of the engine in spite of a reduction in work. 相似文献
9.
M. T. Shervani-Tabar N. Mobadersany S. M. S. Mahmoudi A. Rezaee-Barmi 《Journal of Engineering Mathematics》2011,71(4):349-366
The hydrodynamic behavior of the fluid around a cavitation bubble located above a rigid boundary is investigated numerically.
The liquid around the cavitation bubble is assumed to be incompressible, inviscid and irrotatational and surface tension is
assumed to be negligible. Boundary-integral-equation and finite-difference methods are employed to study the problem. Three
cases are investigated: (1) when the Bjerknes force is negligible in comparison with the buoyancy force, (2) when the buoyancy
force is negligible in comparison with the Bjerknes force, (3) when the Bjerknes attraction force through the rigid surface
and the buoyancy force are comparable. It is shown that during the collapse phase in the third case, an annular liquid jet
develops around the bubble, causing it to take the shape of an hour-glass. This phenomenon is called necking which is followed
by splitting the bubble into two parts. Features to note are the large lateral pressures and the high relative velocities
of the fluid particles near the annular liquid jet of the bubble. This large lateral pressure may be the cause of bubble collapse.
The velocity field of the liquid domain around the two parts of the cavitation bubble after splitting shows that a stagnation
point exists between the two parts of the bubble. Because of the unsteady nature of the problem, the stagnation point and
the point of maximum pressure do not coincide. 相似文献
10.
M. Zarrebini M. R. Mahmoudi M. A. El‐Bakary H. M. El‐Dessouky C. A. Lawrence 《应用聚合物科学杂志》2010,115(5):2892-2897
Melt spinning and pump speed conditions are described for five samples of staple polypropylene PP fibers of different fineness. The influence of fiber fineness or denier on the physical characteristics of staple PP fibers spun at different pump speeds was studied. Optical anisotropy was measured using two‐beam interference microscopy. Enthalpy and degree of crystallinity were measured using differential scanning calorimetry technique for studied fibers. The relation between the fiber diameter, crimp ratio, tenacity, and degree of orientation with the fiber denier are given. A selection of microinterferograms of fibers is given for illustration. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献