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91.
This article scrutinizes the features of viscous dissipation in the stagnation point flow past through a linearly stretched Riga wall by implementing Cattaneo-Christov heat flux model. Viscous dissipation is carried out in Cattaneo-Christov diffusion analysis for the first time in this letter. As a result of Cattaneo-Christov model, some extra terms of viscous dissipation are appeared in the energy equation. These extra terms of viscous dissipation are missing in the literature. On the utilization of suitable transformations, the equations governing the problem are reduced under the boundary layer approximation into the non-linear and dimensionless ordinary differential equations. Convergent approach is utilized to solve the dimensionless governing equations. The solution thus acquired is used to highlight the effects of emerging parameters on velocity distribution and fluid's temperature through the graphs. Features of the drag force (or skin friction co-efficient) are graphically interpreted. It is noticed that the presence of modified Hartman number helps to reduce the fluid's temperature but enhances the velocity profile. Further an enlargement in the value of thermal time relaxation parameter helps to decrease the temperature distribution. 相似文献
92.
Nanosecond pulse generation in an erbium-doped fiber laser (EDFL) passively mode-locked by a silver nanoparticle(SNP)-based saturable absorber(SA) is experimentally demonstrated. The SA is fabricated by depositing a nanosized SNP layer onto the surface of polyvinyl alcohol film through the thermal evaporation process. By inserting the SA into an EDFL cavity, stable mode-locked operation is achieved at 1561.5 nm with the maximum pulse energy up to 52.3 nJ. The laser operates at a pulse repetition frequency of 1.0 MHz with a pulse width of 202 ns. These results suggest that SNPs could be developed as an effective SA for mode-locking pulse generation. 相似文献
93.
94.
A unified higher-order dual for a nondifferentiable minimax programming problem is formulated. Weak, strong and strict converse
duality theorems are discussed involving generalized higher-order (F,α,ρ,d)-Type I functions.
The research of second author was supported by the Department of Atomic Energy, Government of India, under the NBHM Post Doctoral
Fellowship Program 40/9/2005-R&D II/2398. 相似文献
95.
Solid polymer electrolyte films based on poly(vinyl chloride)-lithium triflate (PVC-LiCF3SO3) have been prepared by the solution-cast technique in various concentrations. The film with the highest conductivity was
used to prepare plasticised polymer electrolyte films by using poly(ethlene glycol) (PEG) of different molecular weights,
i.e., 200, 400 and 600 gmol−1. These films were prepared to study the effects of addition of low molecular weights PEG on the lithium ionic conduction
of the PVC based polymer electrolyte. The films were characterised by electrochemical impedance spectroscopy (EIS) and Fourier
transform infrared-spectroscopy (FTIR). Results indicate that the molecular weight has an inverse effect on the conductivity
and this has been accounted for by FTIR.
Paper presented at the International Conference on Functional Materials and Devices 2005, Kuala Lumpur, Malaysia, June 6 –
8, 2005. 相似文献
96.
Zhengjun Liu Jingmin Dai Xiaoyi Zhao Xiaogang Sun Shutian Liu Muhammad Ashfaq Ahmad 《Optics and Lasers in Engineering》2009,47(11):1250-1253
A simple but effective scheme to generate dark hollow beams is proposed by use of phase-only filtering and optical Fourier transform. A Gaussian beam of fundamental mode is modulated by a pre-designed phase mask, which is a piecewise modification of an axicon lens, and followed by a Fourier transform to generate an ideal dark hollow beam at the focal plane. This method has an advantage that the total energy of the beam is conserved under paraxial approximation. Numerical calculations are provided to show the validity of the proposed scheme. 相似文献
97.
In this paper, an algorithm based on the regularization and integral mean value methods, to handle the ill-posed multi-dimensional Fredholm equations, is introduced. The application of this algorithm is based on the transforming the first kind equation to a second kind equation by the regularization method. Then, by converting the first kind to a second kind, the integral mean value method is employed to handle the resulting Fredholm integral equations of the second kind. The efficiency of the approach will be shown by applying the procedure on some examples. 相似文献
98.
Jabbar A Tufail M Arshed W Bhatti AS Ahmad SS Akhter P Dilband M 《Isotopes in environmental and health studies》2010,46(4):495-505
In Rechna Doab, samples of the most common vegetation, perennial grass Desmostachya bipinnata (dab), were collected along with soil samples from 29 sites. Natural radioactivity of 22?Ra, 232Th/22?Ac and ??K was measured by using high purity germanium-based gamma ray spectrometer. Activity concentration levels of 22?Ra, 232Th/22?Ac and ??K in soil were found to be 46.8 ± 6.2 (36.0-57.6), 61.4 ± 5.9 (48.2-73.2) and 644.8 ± 73.9 (537.7-868.4) Bq kg?1 (dry mass), respectively, and those in vegetation were 2.74 ± 1.70 (1.00-6.39), 2.24 ± 0.59 (1.56-2.61) and 172.72±113.37 (53.14-469.24) Bq kg?1 (dry mass), respectively. The measured values of the activity concentration in vegetation are comparable with some other international data. Calculated soil to vegetation transfer factors of 22?Ra, 22?Ac and ??K were 0.06 ± 0.03 (0.02-0.14), 0.04 ± 0.01 (0.03-0.04) and 0.26 ± 0.16 (0.09-0.69). The mean outdoor absorbed dose rate in air for the area under study was determined as 8.22 nGy h?1 and the mean indoor absorbed dose rate in air was 11.52 nGy h?1. The total annual effective dose to the general public from the vegetation was found to be (0.02-0.16) mSv, which is below the recommended limit value of 1 mSv y?1 for the general public. The dab vegetation under study was found to be radiologically safe for the population and environment. 相似文献
99.
Rami Ahmad El-Nabulsi 《理论物理通讯》2019,71(7):831-836
We discuss a particular four-dimensional cosmology based on non-minimal scalar tensor theories characterized by a supersymmetric loop corrected potential and a Hubble parameter defined as a function of the scalar field. Power-law solutions are obtained in the FRW background giving rise to acceleratedly expanding universe characterized by a scale factor and a scalar field depending both on the non-minimal coupling parameter $\xi$. Based on SNeIa data and on Hubble data X-ray gas mass fraction measurements, we find $0.116<\xi <0.225$ which results on a universe dominated by vacuum energy. 相似文献
100.
Nasim Ahmed Syed Alwee Aljunid R. Badlishah Ahmad Hilal A. Fadhil Mohd Abdur Rashid 《Optical Review》2012,19(1):1-6
The bit-error rate (BER) performance of the spectral amplitude coding-optical code division multiple access (SACOCDMA) system
has been investigated by using NAND subtraction detection technique with enhanced double weight (EDW) code. The EDW code is
the enhanced version of double weight (DW) code family where the code weight is any odd number and greater than one with ideal
cross-correlation. In order to evaluate the performance of the system, we used mathematical analysis extensively along with
the simulation experiment. The evaluation results obtained using the NAND subtraction detection technique was compared with
those obtained using the complementary detection technique for the same number of active users. The comparison results revealed
that the BER performance of the system using NAND subtraction detection technique has greatly been improved as compared to
the complementary technique. 相似文献