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排序方式: 共有141条查询结果,搜索用时 15 毫秒
81.
Journal of Thermal Analysis and Calorimetry - This paper deals with the numerical solution of a multi-reaction model for the complex thermal history. The effect of thermal and kinetic parameters is... 相似文献
82.
Attar Suraj R. Shinde Bipin Kamble Santosh B. 《Research on Chemical Intermediates》2020,46(10):4723-4748
Research on Chemical Intermediates - Mushroom-like mesoporous and hexagonal ZnO nanoparticles were synthesized from plant extract and chemical method respectively, by co-precipitation method in... 相似文献
83.
Time harmonic waves in a swelling porous elastic medium of infinite extent and consisting of solid, liquid and gas phases have been studied. Employing Eringen’s theory of swelling porous media, it has been shown that there exist three dilatational and two shear waves propagating with distinct velocities. The velocities of these waves are found to be frequency dependent and complex valued, showing that the waves are attenuating in nature. Here, the appearance of an additional shear wave is new and arises due to swelling phenomena of the medium, which disappears in the absence of swelling. The reflection phenomenon of an incident dilatational wave from a stress-free plane boundary of a porous elastic half-space has been investigated for two types of boundary surfaces: (i) surface having open pores and (ii) surface having sealed pores. Using appropriate boundary conditions for these boundary surfaces, the equations giving the reflection coefficients corresponding to various reflected waves are presented. Numerical computations are performed for a specific model consisting of sandstone, water and carbon dioxide as solid, liquid and gas phases, respectively, of the porous medium. The variations of phase speeds and their corresponding attenuation coefficients are depicted against frequency parameter for all the existing waves. The variations of reflection coefficients and corresponding energy ratios against the angle of incidence are also computed and depicted graphically. It has been shown that in a limiting case, Eringen’s theory of swelling porous media reduces to Tuncay and Corapcioglu theory of porous media containing two immiscible fluids. The various numerical results under these two theories have been compared graphically. 相似文献
84.
Euaggelos E. Zotos Wei Chen Md Sanam Suraj Rajiv Aggarwal Charanpreet Kaur 《Journal of Nonlinear Modeling and Analysis》2020,2(4):551-564
The scope of this work is to reveal, by means of numerical methods, the escape process in a Hamiltonian system with five exits which describes
the problem of rearrangement multichannel scattering. For determining the
influence of the energy on the nature of the orbits we classify starting conditions of orbits in planes of two dimensions. All the complex basins of escape,
associated with the five escape channels of the system, are illustrated by using
color-coded diagrams. The distribution of time of the escape is correlated with
the corresponding escape basins. The uncertainty (fractal) dimension along
with the (boundary) basin entropy are computed for quantifying the degree of
fractality of the dynamical system. 相似文献
85.
Hemalatha T Mala VV Manohar BM Nayeem M Subramaniam S Puvanakrishnan R 《Cryo letters》2006,27(5):311-318
Cryoinfarction in rats was carried out by placing the cooled probe directly on the midway of left anterior descending coronary artery. This caused damage to the blood vessel, hindering blood flow to the distal part of the left ventricle. Gross pathology showed around 26% infarction at 24 h. Histopathology revealed death of cardiomyocytes with blood vessel congestion at the end of 24 h, inflammatory infiltrate at 48 h, fibrotic scar by 96 h and collagen deposition by 192 h. Acute myocardial infarction biomarkers such as Cardiac Troponin T, Creatine Kinase MB and NT pro BNP were shown to be elevated by 4 h. ECG showed an ST segment elevation by 96 h. This cryoinfarction model was suitable to study changes taking place during acute myocardial infarction in humans. 相似文献
86.
Rajdeep Sarkar Vajinder Singh Suraj Kumar Y. Venkateswara Rao P. Ghosal T. K. Nandy 《哲学杂志》2019,99(10):1240-1258
The aim of this investigation is crystal structure determination of an intermetallic phase formed in a W-Ni-Co alloy during a heat-treatment carried out at a temperature of 800°C. This intermetallic phase is expected to play a critical role on the final microstructure (fine tungsten particles in an FCC matrix that is present in between large tungsten grains) and thereby, on the properties of the alloy. 92W-5.3Ni-2.7Co alloy was prepared through powder metallurgy route (liquid phase sintering) followed by heat-treatment at 800°C for 5?h. The intermetallic phase formed at this temperature was characterised using transmission and scanning electron microscopes. The intermetallic phase was found to have orthorhombic crystal structure with Pnam (62) space group as determined using automated diffraction tomography along with precession electron diffraction. Chemical analysis in TEM suggested that the intermetallic phase is based on stoichiometry (Co,Ni)2W. Orientation imaging of the phase was also carried out in TEM and EBSD to understand its evolution. Equiaxed or lath morphology of the intermetallic phase was found to depend on the crystallographic orientation relationship of the phase with the tungsten grains and the matrix phase. 相似文献
87.
88.
R. Thiagarajan V. Kalpagam U. S. Nandi 《Journal of polymer science. Part A, Polymer chemistry》1982,20(3):675-681
Polymerization of methyl methacrylate in the presence of a mixed ligand complex, [N,N′-ethylenebis(salicylideneiminato)](acetylacetonato)cobalt(III) in benzene was studied. The rate of polymerization was proportional to the square root of the concentration of the chelate and the monomer exponent was 1.67 and 1.69 at 60 and 70°C, respectively. The activation energy and the kinetic and transfer constants were evaluated. A free-radical mechanism has been proposed. 相似文献
89.
The mixed gas (Ar + N2) plasma has been generated by a 6 KW, 10.3 MHz radio frequency oscillator. The flame got extinguished if N2 exceeded more than 20% of Ar. The Boltzmann plot using spectral intensities of Ar I and NI lines in the wavelength range 4000–4510 Å have been used to determine the excitation temperature. The results show that excitation equilibrium between two species exist since the temperatures are found to be nearly same for both species. 相似文献
90.
Bajaj S. D. Mahodaya O. A. Tekade P. V. Patil V. B. Kukade Suraj D. 《Russian Journal of General Chemistry》2017,87(3):546-549
Russian Journal of General Chemistry - A simple and efficient method of one pot synthesis of 1,4-dihydropyridine by three components reaction of aromatic aldehydes with 1,3-dicarbonyl compound,... 相似文献