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111.
Resonant oscillations of a plate in an electrically conducting rotating Johnson-Segalman fluid 总被引:1,自引:0,他引:1
An analysis of hydromagnetic flow is examined in a semi-infinite expanse of electrically conducting rotating Johnson-Segalman fluid bounded by nonconducting plate in the presence of a transverse magnetic field and the governing equations are modeled first time. The structure of the velocity distribution and the associated hydromagnetic boundary layers are investigated including the case of resonant oscillations. It is shown that unlike the hydrodynamic situation for the case of resonance, the hydromagnetic steady solution satisfies the boundary condition at infinity. The inherent difficulty involved in the hydrodynamic resonance case has been resolved in the presence analysis. 相似文献
112.
The influence of Hall currents and rotation on the oscillatory flows of an infinite plate is investigated. Exact solutions for the two problems are obtained.The fluid considered is a homogeneous Oldroyd-B. During the mathematical analysis it is found that governing differential equation for steady flow in an Oldroyd-B fluid is identical to that of viscous fluid. Further, it is observed that in absence of the strength of transverse magnetic field (B0) the solution in resonance case does not satisfy the boundary condition at infinity. Physical significance of mathematical results is also discussed. 相似文献
113.
Ahmad Faraz Mohammad Faizan Fareen Sami Husna Siddiqui John Pichtel Shamsul Hayat 《IET nanobiotechnology / IET》2019,13(4):345
Nanotechnology is an emerging field of science that applies particles between 1 and 100 nm in size for a range of practical uses. Nano‐technological discoveries have opened novel applications in biotechnology and agriculture. Many reactions involving nanoparticles (NPs) are more efficient compared to those of their respective bulk materials. NPs obtained from plant material, denoted as biogenic or phytosynthesised NPs, are preferred over chemically synthesised NPs due to their low toxicity, rapid reactions and cost‐effective production. NPs impart both positive and negative impacts on plant growth and development. NPs exhibit their unique actions as a function of their size, reactivity, surface area and concentration. An insight into NP biosynthesis and translocation within the plant system will shed some light on the roles and mechanisms of NP‐mediated regulation of plant metabolism. This review is a step towards that goal.Inspec keywords: nanofabrication, nanoparticles, nanobiotechnology, particle size, reviews, botany, biochemistryOther keywords: chemically synthesised NPs, low toxicity, rapid reactions, cost‐effective production, positive impacts, plant growth, translocation, plant system, plant metabolism, nanotechnological discoveries, biotechnology, agriculture, plant material, biogenic NPs, phytosynthesised NPs, bulk materials, nanoparticles, biosynthesis, surface area, review, size 1.0 nm to 100.0 nm 相似文献
114.
T. Hayat Z. Iqbal M. Sajid K. Vajravelu 《International Communications in Heat and Mass Transfer》2008
A mathematical model for flow and heat transfer has been presented for Johnson–Segalman fluid in a pipe. Employing homotopy analysis method, the developed equations are solved analytically. The velocity and temperature fields are obtained. The dependence of the flow quantities on the material properties and Brinkman number is determined. 相似文献
115.
Dhakal S. Hayat M.M. Pezoa J.E. 《Parallel and Distributed Systems, IEEE Transactions on》2007,18(4):474-484
A regeneration-theory approach is undertaken to analytically characterize the average overall completion time in a distributed system. The approach considers the heterogeneity in the processing rates of the nodes as well as the randomness in the delays imposed by the communication medium. The optimal one-shot load balancing policy is developed and subsequently extended to develop an autonomous and distributed load-balancing policy that can dynamically reallocate incoming external loads at each node. This adaptive and dynamic load balancing policy is implemented and evaluated in a two-node distributed system. The performance of the proposed dynamic load-balancing policy is compared to that of static policies as well as existing dynamic load-balancing policies by considering the average completion time per task and the system processing rate in the presence of random arrivals of the external loads 相似文献
116.
Summary We obtain a new exact power law solution for the pipe flow of a third-grade fluid. Moreover, we provide general analytical
expressions from which all previous known solutions can be constructed. 相似文献
117.
S Keating T de Witte S Suciu R Willemze M Hayat B Labar L Resegotti PR Ferrini F Caronia M Dardenne G Solbu MC Petti ML Vegna F Mandelli RA Zittoun 《Canadian Metallurgical Quarterly》1998,102(5):1344-1353
To determine whether patients with a HLA-identical sibling donor have a better outcome than patients without a donor, an analysis on the basis of intention-to-treat principles was performed within the framework of the EORTC-GIMEMA randomized phase III AML 8A trial. Patients in complete remission (CR) received one intensive consolidation course. Patients with a histocompatible sibling donor were then allocated allogeneic bone marrow transplantation (alloBMT), the patients without a donor were randomized between autologous BMT (ABMT) and a second intensive consolidation (IC2). 831 patients <46 years old and alive >8 weeks from diagnosis were included. HLA typing was performed in 672 patients. AlloBMT was performed during CR1 in 180 (61%) out of 295 patients with a donor. Another 38 patients were allografted: five in resistant disease, 14 during relapse and 19 in CR2. ABMT was performed in 130 (34%) out of 377 patients without a donor in CR1, in six (2%) patients during relapse and in 38 (10%) patients during CR2. The disease-free survival (DFS) from CR for patients with a donor was significantly longer than for patients without a donor (46% v 33% at 6 years; P=0.01, RR 0.78, 95% confidence interval 0.63-0.96). The overall survival from diagnosis for patients with a donor was longer, but not statistically significant, than for patients without a donor (48% v 40% at 6 years; logrank P=0.24). When patients were stratified according to prognostic risk groups, the same trend in favour of patients with a donor was seen for survival duration and the DFS remained significantly longer for this group of patients. 相似文献
118.
119.
Summary An exact solution of the unsteady flow of a second-order fluid due to non-coaxial rotations of a porous disk and a fluid at infinity in the presence of a uniform transverse magnetic field is investigated. It is once again shown that for uniform suction or uniform injection at the disk an asymptotic profile exists for the velocity distribution. The effects of the magnetic field, the material parameters of the second-order fluid, suction and injection on the velocity distribution are studied. Further, from the solution of a rigid disk, it is found that for parameter >.01, a non-Newtonian effect is present in the velocity field. However, for <.01 the velocity field becomes a Newtonian one. 相似文献
120.
Summary An analysis is carried out to study the flow characteristics in an elastico-viscous fluid (Walters' liquid-B model) over a
stretching sheet with partial slip. The flow is generated due to linear stretching of the sheet. Using suitable similarity
transformations on the highly non-linear partial differential equations we derive exact analytical solution with appropriate
boundary conditions. The important finding in this communication is the effect of partial slip on the velocity and skin friction
coefficient. 相似文献