Search

The thermal management system of battery pack was investigated based on the combination of two different phase change materials OM35 and Paraffin wax coupled with forced air cooling to maintain the...

Flax fiber-containing polypropylene-based polymer matrix composites (PMCs) with different lignite fly ash (LFA) contents were synthesized using the formula (80 − x) PP − 20 F – x LFA (where x = 0, ...

Fixed displacement gerotor oil pumps are widely used in the IC engine lubrication system due to their simple geometry and low cost. As the future focuses on decreasing the power consumption of oil ...

A numerical investigation is carried out to analyze forced convection heat transfer in magnetohydrodynamic (MHD) flow past a circular cylinder by considering the penetration of magnetic field insid...

When a truck undergoes acceleration, braking, turning, etc., sloshing of the fuel occurs in the tank. Sloshing can be defined as a non-linear or irregular motion of free surface of fuel inside the ...

As fossil fuels are depleting gradually with the course of time there is a need for developing innovative products that can extract maximum potential that the system can deliver. One of the key are...

Purpose: To analyze the diagnostic predictive ability of clinical variables.Methods: Demographic and clinical variables of 172 serologically proven leptospiral uveitis patients were compared with 200 controls of non-leptospiral uveitis. Multiple logistic regression analysis identified diagnostic predictors. A receiver operating characteristic curve tested the performance of the model.Results: Of all variables, male gender, farming as an occupation, and clinical features such as non-granulomatous panuveitis, hypopyon, and vitreous infiltration in the absence of retinochoroiditis constituted the predictive parameters, with the sensitivity and specificity of 86% and 90.7%, respectively.Conclusions: Multiple logistic analysis detected clinically diagnostic predictors that can assist primary care ophthalmologists. Clinical diagnosis can further be confirmed by serology at tertiary care centers.

The increasing demand on energy due to population growth and rising of living standards has led to considerable use of fossil fuels which has in turn, had an adverse impact on environmental pollution and depletion of fossil fuels in Internal Combustion (IC) engine sector. Alternative fuel blend evaluation in IC engine fuel technologies is a very important strategic decision involving decisions balancing within a number of criteria and opinions from different decision maker of IC engine experts. The selection of appropriate source of biodiesel and proper blending of biodiesel plays a major role in alternate energy production. This paper describes an application of hybrid Multi Criteria Decision Making (MCDM) technique for the selection of optimum biodiesel blend in the IC engine. The proposed model, Analytical Network Process (ANP) is integrated with Technique for Order Performance by Similarity to Ideal Solution (TOPSIS) to evaluate the optimum blend. Here the ANP is used to determine the relative...

CuInGaS2 (CIGS) thin films were fabricated by DC magnetron sputtering by varying the sputtering power (70, 90, 110 and 130 W). The X-ray diffraction revealed the formation of tetragonal structure with (1 1 2) preferential orientation. The film prepared at 90 W has better crystallinity with minimum dislocation density and strain. From the scanning electron microscopy analysis, it was found to be a denser and larger in grain formation. The elemental quantification and stoichiometric ratio of the CIGS films were confirmed by energy-dispersive spectra. The optical band gap was found using Tauc plot, and it varied from 1.20 to 1.52 eV. The transport conduction mechanism involved in CIGS films was identified from DC four-probe method. Raman studies reveal that all the films composed of CH and CA ordering. The solar cell measurements indicate that high power conversion efficiency (η) of 0.29% and short-circuit current density of (Jsc) of 4.51 mA/cm2 obtained for the film deposited at 90 W.

This paper studies the influence of an induced magnetic field on the forced convective heat transfer from an isothermal sphere in the presence of an applied magnetic field. Irrespective of the choice of magnetic Reynolds number, the induced magnetic field is also taken into consideration and, therefore, we have solved the full-magnetohydrodynamic equations in (ψ-ω-A) formulation. We have used a higher order numerical scheme with compact stencil in spherical polar coordinates for discretization. We have observed that the application of magnetic field on the flow has a twofold effect. Firstly the recirculation bubble vanishes, and secondly it alters the heat transfer coefficient. In particular, the heat transfer gets enhanced near the top of the sphere, while in the upstream and downstream regions, it diminishes. We have also found that the magnetic Reynolds number aids in the reduction of heat transfer. Our results on the heat transfer coefficient in the liquid sodium flow problem concur with the available...

Steady, laminar flow of an incompressible fluid with mixed convection over an isothermal circular cylinder is considered. The governing full nonlinear Navier–Stokes equations with energy equation are solved by using a high-accuracy finite difference scheme in cylindrical polar coordinates. The results are discussed in detail for 5 ≤ Re ≤ 40, 0.7 ≤ Pr ≤ 7, and 0 ≤ Ri ≤ 4 and the results are in agreement with the experimental and other computed data. An increase in the mixed convection parameter leads to reduction of the drag coefficient. The fluid with higher Pr generates vortices that destabilize the flow. The local Nu for the mixed convection cases are higher than the pure forced convection counterparts. The normalized mean Nusselt number (Nm) does not significantly change for flows with very small Richardson numbers. However, for larger Ri, it increases linearly with Ri.

A simple, modified, cold spray process was developed in which hydroxyapatite powder was coated onto pure magnesium substrates preheated to 350 or 550°C and ground to either 240 or 2000 grit surface roughness, with stand-off distances of 20 or 40 mm. The procedure was repeated five and 10 times. The hydroxyapatite coatings did not show any phase changes. Atomic force microscopy revealed a uniform coating topography, and scanning electron microscopy revealed good bonding between the coated layers and the substrates. As the p values were

To describe the clinical and histopathological features of post viper bite anterior segment ischemia.Seven patients with ocular complications following viper bite referred to uveitis clinic had slit-lamp examination, intraocular pressure (IOP) measurement, and fundus evaluation. Iris and fundus fluorescein angiography was performed on 2 patients. Histopathological examination was performed on iris tissues collected during cataract surgery.Strikingly similar clinical findings were noted, including circumpupillary superficial iris atrophy, mid dilated fixed pupil, marked pigment dispersion, low IOP, and cataract. All clinical signs were noted only in the anterior segment; the posterior segment was normal. Histopathology of iris revealed atrophy of iris stroma, necrotic iris pigment epithelium, and infiltration of T lymphocytes and fibrous membrane. Poor visual outcome was noted in patients with low IOP.Viper bite victims presented with clinical and histopathological signs of anterior segment ischemia and secondary inflammatory signs mimicking uveitis.

In this study, we developed an effective technology for the extraction of sericin from the cocoons of Bombyx mori silk worms. Sericin was extracted with ice cold ethanol to obtain crude extract. Sericin extract was coated onto cotton fabric by a pad–dry–cure method. FTIR characterization of the sericin-coated cotton fabric showed distinct amide peaks. The test organisms that were used in the study to assess the antimicrobial activity of sericin were Escherichia coli and Staphylococcus aureus according to AATCC standard. The antimicrobial activity of the sericin thus extracted was assessed by both qualitative (agar diffusion and parallel streak method) and quantitative (percentage reduction test) methods. An inhibition zone of 28 mm and 30 mm for E. coli and S. aureus by agar diffusion method and a zone of 40 mm and 42 mm for E. coli and S. aureus by parallel streak method were obtained. Quantitative assessment by percentage reduction test showed a reduction percentage of 89.4% and 81% for S. aureus and E....

Results from three-dimensional (3D) unsteady numerical simulations of turbulent, bluff-body, stabilized, lean, premixed combustion are reported. Shear stress transport (SST) k model has been used for modeling turbulence, while a detailed 43-step mechanism has been used for modeling the methane, air chemistry. Turbulence chemistry interaction has been modeled using the eddy dissipation concept. Calculation has been done with buoyancy effects included to account for the effect of buoyancy on the predicted results. The three dimensionality of the flame is clearly demonstrated through velocity and temperature profiles. The intensity of turbulence is greatly enhanced by the flame, which is located at the shear layer, and thus the role of the flame as a turbulence generator is highlighted. The shear layer separates the cold reactants and the hot products, and is thus highly strained. The spectral analysis of time histories of pressure and velocity reveal that the lowest and highest dominant frequencies correspond to the vortex shedding mode and instability mode, respectively. Predicted numerical results [both mean as well as root mean square (RMS) values] are compared with the experimental data reported by Nandula et al. (S. P. Nandula, R. W. Pitz, R. S. Barlow, and G. J. Fiechtner, Rayleigh/Raman/LIF Measurements in a Turbulent Lean Premixed Combustor, AIAA-96-0937, 1996). � 2012 Copyright Taylor and Francis Group, LLC.

Electrochromic thin films of molybdenum oxide (MoO3) were prepared on transparent conducting oxide substrates, i.e. fluorine doped tin oxide coated (FTO or SnO2:F) glass substrates by electron beam evaporation technique using pure MoO3 (99.99%) pellets at various substrate temperatures (i.e. Tsub=room temperature (30°C), 100 and 200°C) under the vacuum of 1 × 10−5 mbar. The room temperature prepared films were further annealed Tanne at 200 and 300°C for about one hour in the vacuum environment. The electrochemical nature of the films was studied by the cyclic voltammetry technique using a three electrode electrochemical cell in 0·1M LiClO4.PC electrolyte. The performance of the films was also tested by making electrochromic cells. The films produced at higher substrate temperature show lesser modulation in the visible spectrum, compared with the films produced at lower temperatures. A maximum colouration efficiency of 66 cm2 C−1 was observed in the infrared region for the films prepared at room te...

In the present paper, the authors report on the electrochromic properties of electron beam evaporated tungsten oxide (WO3) thin films at different electrolytes. The authors observe the better electrochromic performance for the as deposited room temperature prepared films than the higher substrate temperature prepared films and annealed films. In addition, the less reversible coloration was observed for the heavier ion (K+) intercalation/deintercalation than the lighter one (Li+), which may be due to the effect of microstructure of the films, and ion mobility. The possible role of electrochromic performance in the mechanism of film crystallinity has been discussed.

CdS and CdZnS films were successfully deposited on glass/indium tin oxide (ITO) substrates from an aqueous solution. The ratio of Cd/Zn has been identified by auger electron spectroscopy (AES). The deposited films have been confirmed by X-ray diffraction (XRD) and were found to crystallise in the hexagonal crystal system. The surface of the as deposited and annealed films was analysed using SEM. The improvement of crystallinity was confirmed by Raman spectroscopy and XRD. Photoelectrochemical studies were carried out by fabricating a PEC cell of configuration CdS/0·1M Na2SO4/ITO and the physical parameters were studied. Current–voltage measurements were performed. The results of the present investigation are discussed in detail.

The present work is concerned with tungsten oxide (WO3) thin films, which feature strongly in electrochromic applications. The films were deposited on glass substrates and fluorine doped tin oxide (FTO) coated glass substrates by the electron beam evaporation technique using a WO3 target. The elemental analysis of the films was performed by particle induced X-ray emission (PIXE) spectroscopy, and the surface morphology of the films was studied using atomic force microscopy (AFM). To the best of our knowledge, this is the first time that PIXE has been used for the analysis of elements present in electron beam evaporated WO3 films. In this study, PIXE was applied to confirm the presence of constituent element in the films. Atomic force microscopic studies revealed that the deposited WO3 films are homogeneous, crack-free surfaces with uniform spherical nanograins. These characterisation studies were carried out for the films prepared on different substrates, and at different deposition temperatures ...

To investigate the dose-dependent effects of gamma radiation on rat Leydig cell luteinizing hormone (LH) receptor expression, signal transduction and steroidogenesis.Leydig cells isolated from testicles of adult male albino rats were cultured and exposed to different doses (2, 4, 6, 8 and 10 Gy) of fractioned gamma radiation for three days. Normal as well as irradiated cells were used for the quantification of cell surface LH receptor or LH/cyclic adenosine monophosphate (cAMP) stimulation test or total ribonucleic acid (RNA) isolation to study the LH receptor messenger RNA (mRNA) expression by reverse transcriptase polymerase chain reaction (RT-PCR).Radiation was found to have dose-dependent effects on rat Leydig cell surface LH receptor, basal and LH-stimulated cAMP production, basal, LH and cAMP-stimulated steroidogenesis. Lower doses (2 and 4 Gy) of radiation did not induce any change, whereas higher doses (6, 8 and 10 Gy) of radiation exposure diminished the above said parameters significantly. In spite of the low level of cell surface LH receptors following higher doses of radiation exposure, its mRNA level was not altered under any dose level.From these observations, it is concluded that gamma radiation has dose-dependent inhibitory effects on Leydig cell LH signal transduction and steroidogenesis. Decreased cell surface LH receptor following higher doses of radiation exposure is not coupled with altered LH receptor mRNA level.

Thin films of molybdenum oxide (MoO3) were deposited by a physical vapour deposition method, i.e.the electron beam evaporation technique, using Corning 7059 microscopic glass and SnO2:F as substrates. The effects of annealing temperature on the structural, surface morphological and optical properties of the films were studied and the results are discussed in detail.

Biomaterials play a key role in the medical devices and implants used for diagnostic or therapeutic purposes. Among these, the ceramic materials, though not occupying the leading role like polymers...

The pitting corrosion resistance of AISI 304 stainless steel (SS), which was laser melted in both nitrogen and argon atmosphere, was studied using the potentiodynamic anodic polarisation method. An attempt was made to introduce nitrogen onto the surface layers by melting in nitrogen atmosphere and argon atmosphere using a continuous wave CO2 laser as the heat source at a power output of 3·06 kW at the laser head. The pitting corrosion resistance was determined by measuring the critical pitting potential during anodic polarisation. Secondary ion mass spectrometry (SIMS) was carried out on the laser melted surface to characterise the chemical composition. It was found that the pitting corrosion resistance of 304 SS was improved when laser surface melting was carried out in argon and was improved further when melting was carried out in nitrogen atmosphere. However, the improvement in pitting corrosion resistance in laser melted material was observed only in the reabraded condition and the pitting cor...

A theoretical prediction model is presented to estimate the in-flight velocity, temperature, and size of a ceramic particle traversing through a plasma flame. The model accounts for the various phenomena that can influence the transport rate calculations in plasma spraying operations, which typically involve very fine particles (

In recent years, the use of plasma-sprayed protective coatings has gained increasing acceptance for prolonging the service life of critical components exposed to aggressive environments during normal operation. This paper is aimed at providing an overview of the current state-of-the-art of the plasma coating technology. It includes a brief discussion of the various important aspects associated with the development of reliable protective coatings as well as their evaluation, and outlines some noteworthy advances made in the field of plasma spray materials and equipment in the past few years. The various factors influencing the coating quality are identified and the wide-ranging utility of plasma-sprayed coatings is also highlighted.

Plasma-sprayed coatings are used in a wide range of engineering applications to combat oxidation, corrosion and wear. The plasma spraying process is ideally suited for refractory materials, but there are a number of process variables that need be controlled to obtain dense coatings. In spite of the considerable progress made in the theoretical understanding of this complex process, there is a need for a simple method to evaluate the interaction between the plasma flame and the powder particles that fonn the coatings. As reported in the literature, this involves metallographic observation of the powders collected from the plasma. In this paper, the results of such a study are presented. It is shown that this method is effective in detennining the extent of melting and the relative velocity of both metallic and ceramic powders.

MCrAlY coatings (M = Ni, Co, Fe alone or in combination) are currently used to protect gas turbine blades and vanes from oxidation and hot corrosion. The coatings are required to be fully dense and well bonded to the substrate. They are formed either by electron beam evaporation or by low pressure plasma spraying. Another possible route is to form them by normal atmospheric plasma spraying, followed by remelting with a laser to remove porosity and other defects. The feasibility of this approach has been investigated by melting plasma sprayed NiCoCr AIY coatings on a Nimonic 75 substrate. This work focuses mainly on the effect of various laser processing parameters on the structure of remelted layers. Preliminary data on the hot corrosion properties of the laser melted coatings are also presented.