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131.
We considered the magnetohydrodynamic (MHD) free convective flow of an incompressible electrically conducting viscous fluid past an infinite vertical permeable porous plate with a uniform transverse magnetic field, heat source and chemical reaction in a rotating frame taking Hall current effects into account. The momentum equations for the fluid flow during absorbent medium are controlled by the Brinkman model. Through the undisturbed state, both the plate and fluid are in a rigid body rotation by the uniform angular velocity perpendicular to an infinite vertical plate. The perpendicular surface is subject to the homogeneous invariable suction at a right angle to it and the heat on the surface varies about a non-zero unvarying average whereas the warmth of complimentary flow is invariable. The systematic solutions of the velocity, temperature, and concentration distributions are acquired systematically by utilizing the perturbation method. The velocity expressions consist of steady-state and fluctuating situations. It is revealed that the steady part of the velocity field has a three-layer characteristic while the oscillatory part of the fluid field exhibits a multi-layer characteristic. The influence of various governing flow parameters on the velocity, temperature, and concentration are analyzed graphically. We also discuss computational results for the skin friction, Nusselt number, and Sherwood number in the tabular forms. 相似文献
132.
In this research, we utilise a multi-method braided approach for a real-world health care intervention in rural India. We first use action research to conceptually underpin the role of self-help groups, disease profiles and appropriate interventions in health care behaviour change and improvement. Action research is then coupled with a non-linear integer-programming-based simulation to determine how health care resources need to be distributed over time, disease type and groups. The action research provides specific research questions and distributional forms needed for the optimisation analysis, while the non-linear integer-programming simulation provides specific recommendations on where and when to distribute resources. External validity of the study is ensured by the adoption of recommendations in the field as part of the action research. Findings from this research have important policy implications. For example, it identifies the value of continuous embedded interventions as opposed to periodic ones and the importance of flexibility in terms of which community groups and disease types to serve over time. This research also provides an important bridge between the operations research, health care in developing nations, organisational theory and humanitarian operations bodies of knowledge. 相似文献
133.
Abdul Malek Tiju Thomas Edamana Prasad 《International Journal of Hydrogen Energy》2018,43(24):10878-10886
Reaction of Al metal with water is a well-known technique for large scale production of hydrogen. However, this method suffers from kinetic limitations due to formation of a passivation layer on Al, preventing optimal operations. Using high resolution Scanning Kelvin Probe Force Microscopy (SKPFM), we show the origin of formation of 'nano-galvanic couple' on in situ formed nano-aluminum amalgam surfaces in a water splitting system; passivation based limitations are completely bypassed in this approach. Furthermore, they offer an opportunity to beneficiate and recover mercury in contaminated water. The nano-galvanic corrosion due to substantial lateral variation in surface contact potential is responsible for the observed high throughput of hydrogen production (720 mL/min per 0.5 g Al salt). It may be noted that this process fares better than in situ prepared nano-Al based hydrogen production, wherein 600 mL/min of hydrogen is obtained for 0.5 g Al salt. Investigations using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) provide evidence for passivation-bypassed hydrolysis and favourable kinetics for in situ derived nano-AlHg hydrolytic agents (when compared to nano-Al). This study, to the best of our knowledge, reports the first direct proof of nano-galvanic couple formation on in-situ prepared nanoaluminum amalgam surface; paving a direct way to overcome the long standing passivation problem in Al hydrolysis. It is found that the hydrogen production rate and standard deviation (SD) of the contact potential of nanoaluminum amalgam are directly related to the rate of addition of the reducing agent, offering an opportunity for kinetic control for the in situ hydrolytic process. 相似文献
134.
Babak Ghorbani Krishna Vijayaraghavan 《International Journal of Hydrogen Energy》2018,43(20):9733-9748
In the current study, a single cell of a planar SOFC is firstly modeled in 3D using commercial SOFC module of ANSYS Fluent and the results are validated against the experimental investigations in the literature. Many researchers have used ANSYS Fluent for simulating solid oxide fuel cells. However, there is a huge gap in the literature on explaining the detailed procedure that should be followed in order to use this software effectively. A thorough step-by-step approach is presented to provide a deep insight into the software. Thereafter, a simplified quasi-2D method with infinitely shorter computational time is developed and the results are compared with the 3D model. It is found that the reduced model is capable of being utilized as an alternate method for both online diagnosis and designing active control strategies. 相似文献
135.
136.
This paper examines the anticorrosion characteristics of three different benzimidazole derivatives towards mild steel in 0.5?M hydrochloric acid at temperature ranges from 303 to 323?K. The benzimidazole derivatives used for the screening studies are 2-(2-methyl-1H-benzimidazol-1-yl) acethydrazide (EMBAH), 2-(2-ethyl-1H-benzimidazol-1-yl) acethydrazide (EEBAH) and 2-(2-propyl-1H-benzimidazol-1-yl) acethydrazide (EPBAH). The corrosion inhibition was investigated by weight loss, electrochemical impedance spectroscopy and potentiodynamic polarization studies. The adsorption interaction between metal and inhibitor followed Langmuir adsorption isotherm. The Gibb’s free energy values clarify the spontaneous nature of adsorption process. The temperature dependence of inhibition efficiency was explained by considering thermodynamic parameters of adsorption and kinetic parameters of corrosion. These inhibitors showed good efficiency at lower as well as moderately higher temperatures. Quantum chemical calculations were done using DFT at the B3LYP/6-31G1 level to study the electronic properties of the molecules for correlating the inhibitive effect and molecular structure. 相似文献
137.
Wireless Personal Communications - The advancements of technology in the field of communication made WSN based IoT attractive and applicable to various areas. It is comprised IoT nodes that work on... 相似文献
138.
Bharat Kumar Reddy Sanapalli Shivaramakrishnan Balasubramanian Jawahar Natarajan Uday Krishna Baruah 《Drug development and industrial pharmacy》2018,44(10):1650-1658
5-Aminosalicylic acid (5-ASA) is an aminosalicylate anti-inflammatory drug, which is also known as mesalazine or mesalamine. Currently employed in treating inflammatory bowel disease, ulcerative colitis, inflamed anus or rectum, and maintain remission in Crohn's disease. Evidence from the researchers highlighted its significant re-epithelization in allergic asthma, aphthous, and gastric ulcerative conditions. The objective of the study was to formulate the pluronic lecithin organogel (PLO) containing 5-ASA and evaluate its wound-healing ability in a full thickness excision wound rat model. The data obtained from in silico docking studies revealed 5-ASA is having an affinity towards the transforming growth factor-beta (TGF-β) specifically towards beta1. Among various formulations prepared (F1 to F8), F1, and F6 have shown a maximum in vitro drug release with optimum pH and viscosity. From MTT assay it was found that selected PLO formulations showed no toxicity and enhanced cell proliferation in HaCaT cell lines. In vivo wound-healing studies in albino Wistar rats has revealed that PLO accelerates wound closure and reepithelization to the statistically significant level on day 3 (p?.05) in comparison with untreated wounds. In conclusion, the overall results suggest that 5-ASA PLO gel is a potential therapeutic option for the treatments of wounds, however, further studies are highly warrened to determine the various mechanisms of 5-ASA in regulating the cell migration and reepithelization in wound healing to outspread its use in clinics. 相似文献
139.
Microsystem Technologies - In the current paper, a new temperature sensor with improved temperature inaccuracy and with very low power consumption has been designed for avionic industry. The... 相似文献
140.
The objective of this research was to study the performance and emission characteristics of using waste plastic pyrolysis oil in diesel engine without any engine modification. The engine used in this study is a four-stroke single-cylinder naturally aspirated diesel engine (compression ignition). In the present work, the engine fuelled with blends of diesel fuel (DF) with plastic oil in the ratio of 90:10 (blend10%), 80:20 (blend20%), 70:30 (blend30%), and 50:50 (blend50%) are experimentally measured the efficiencies and emissions, analysed the performance, and compared results with that of DF. 相似文献