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排序方式: 共有93条查询结果,搜索用时 15 毫秒
11.
Mediterranean Journal of Mathematics - In this paper, we introduce the k-generalized Stockwell transform on $${\mathbb {R}}$$ . We investigate for this transform the main theorems of Harmonic... 相似文献
12.
Nonlinear Dynamics - Reduced-order models (ROM) of structurally dominated fluid flows have significant applications in science and engineering, such as design, control, and optimization.... 相似文献
13.
Hussain Imtiaz Ma Xiaofeng Wu Linlin Luo Zhenyang 《Cellulose (London, England)》2022,29(10):5725-5743
Cellulose - Self-healing hydrogels that mimic human skin and have numerous senses of external tension and temperature are a current topic in science. However, getting skin-compatible performance... 相似文献
14.
Ashok B. Bhise Dattatray J. Late Bhaskar R. Sathe Mahendra A. More Imtiaz S. Mulla Vijayamohanan K. Pillai Dilip S. Joag 《Solid State Sciences》2009,11(6):1114-1117
Tin oxide submicronwires doped with Fe element were prepared by the thermal evaporation method. Morphological and structural characterizations revealed wires with sub micron size and crystalline in nature. The field electron emission from the single Fe:SnO2 wire was carried out in conventional field emission microscope. The Fowler–Nordheim plot obtained from I–V characteristics of the wire showed a linear behavior typical that of metal. The field enhancement factor estimated from the slope of the F–N plot is 7455 cm?1, indicating that the field emission is from nanometric features of the emitter. A current density of 10 A/cm2 has been obtained at an applied field of 4.845 × 103 V/μm. The field emission current–time record at a current level of 1 μA for more than 3 h duration is promising for various field emissions based applications. 相似文献
15.
Longitudinal and transverse structure functions in decaying nearly homogeneous and isotropic turbulence
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Streamwise evolution of longitudinal and transverse velocity structure functions in a decaying homogeneous and nearly isotropic turbulence is reported for Reynolds numbers Reλ up to 720. First, two theoretical relations between longitudinal and transverse structure functions are examined in the light of recently derived relations and the results show that the low-order transverse structure functions can be well approximated by longitudinal ones within the sub-inertial range. Reconstruction of fourth-order transverse structure functions with a recently proposed relation by Grauer et al. is comparatively less valid than the relation already proposed by Antonia et al. Secondly, extended self-similarity methods are used to measure the scaling exponents up to order eight and the streamwise evolution of scaling exponents is explored. The scaling exponents of longitudinal structure functions are, at first location, close to Zybin’s model, and at the fourth location, close to She–Leveque model. No obvious trend is found for the streamwise evolution of longitudinal scaling exponents, whereas, on the contrary, transverse scaling exponents become slightly smaller with the development of a steamwise direction. Finally, the stremwise variation of the order-dependent isotropy ratio indicates the turbulence at the last location is closer to isotropic than the other three locations. 相似文献
16.
The properties of ion acoustic double layer (IADL) structures in bi-ion plasma with electron trapping are investigated by using the quasi-potential analysis. The κ-distributed trapped electrons number density expression is truncated to some finite order of the electrostatic potential. By utilizing the reductive perturbation method, a modified Schamel equation which describes the evolution of the slow electron acoustic double layer (SEADL) with the modified speed due to the presence of bi-ion species is investigated. The Sagdeev-like potential has been derived which accounts for the effect of the electron trapping and superthermality in a bi-ion plasma. It is found that the superthermality index, the trapping efficiency of electrons, and ion to electron temperature ratio are the inhibiting parameters for the amplitude of the slow electron acoustic double layers (SEADLs). However, the enhanced population of the cold ions is found to play a supportive role for the low frequency DLs in bi-ion plasmas. The illustrations have been presented with the help of the bi-ion plasma parameters in the Earth's ionosphere F-region. 相似文献
17.
Imtiaz Maria Shahid Fiza Hayat Tasawar Alsaedi Ahmed 《Journal of Thermal Analysis and Calorimetry》2020,140(5):2461-2470
Journal of Thermal Analysis and Calorimetry - The present paper explores non-Fourier heat flux theory for Jeffrey fluid flow subject to a rotating disk. The current analysis is executed in the... 相似文献
18.
Karm Hans Masood Parvez Sumera Mahboob Imtiaz‐ud‐Din Muhammad Mazhar Saqib Ali 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(11):m559-m562
The central Ge atoms in the structures of 3‐(2‐fluorophenyl)‐3‐(triphenylgermyl)propionic acid, [Ge(C6H5)3(C9H8FO2)], 3‐(2‐tolyl)‐3‐(tri‐4‐tolylgermyl)propionic acid, [Ge(C7H7)3(C10H11O2)], and 3‐(4‐tolyl)‐3‐(tribenzylgermyl)propionic acid, [Ge(C7H7)3(C10H11O2)], are four‐coordinate with slightly distorted tetrahedral geometry. The Ge—Csp3 distances [1.970 (3)–1.997 (3) Å] are significantly longer than the Ge—Caromatic distances [1.940 (3)–1.959 (2) Å]. In all three structures, the molecules form dimeric pairs about inversion centres through strong hydrogen‐bonding interactions between carboxylic acid groups. 相似文献
19.
M. Afzal Javed Hanif Imtiaz Hanif Riaz Qadeer M. Saleem 《Journal of Radioanalytical and Nuclear Chemistry》1990,139(2):203-214
The samples were introduced into the XRF spectrometer in ordinary flat bottom polyethylene bottles for the estimation of Zr or Hf in presence of one another in solution. By using high voltage (50 kV) and high current (50 mA) least limits of detection obtained were an order of magnitude better than other conventional analytical techniques. Relations of intensity to concentration in various concentration ranges have been determined and the results are compared with those of other analytical techniques. 相似文献
20.
Dr. Raheela Naz Prof. Qinglei Liu Dr. Waseem Abbas Dr. Muhammad Imtiaz Dr. Imran Zada Dr. Javed Ahmad Dr. Tengfei Li Prof. Jiajun Gu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(70):16054-16062
A new ternary composite of 1T-molybdenum disulfide, hexagonal tungsten trioxide, and reduced graphene oxide (M-W-rGO) is synthesized by using a one-pot hydrothermal process. The synergetic effect of 1T-MoS2 and hexa-WO3 nanoflowers improves the electrochemical performance for supercapacitors by inducing additional active sites and hexagonal tunnels, respectively, which lead to high storage capacity and easy transfer of electrolyte ions. The ternary M-W-rGO composite has a high specific capacitance of 836 F g−1 at 1 A g−1, which is nearly twice that of binary composites of M-rGO and W-rGO with high capacitance retention of 86.35 % after 3000 cycles at a high current density of 5 A g−1. This study provides a new ternary composite that can be used as an electrode material for high-performance supercapacitors. 相似文献