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991.
R. N. Mulik L. P. Deshmukh V. B. Patil 《Journal of Materials Science: Materials in Electronics》2004,15(6):335-340
An electrochemical solar cell behavior of a mixed type n-Cd1–x
Pb
x
Se (0x0.5) thin film electrode is presented in this paper. A series of the electrodes were prepared for the values of x in the above range and the electrochemical cells of the configuration n-Cd1–x
Pb
x
Se/K4Fe(CN)6/C were fabricated. The current–voltage and capacitance–voltage characteristics of the as-fabricated cells in dark were examined to understand nature of the charge transfer process across the electrode/electrolyte interface. These cells were then illuminated with a light of 20 mW cm–2 intensity and the power output curves were obtained and analyzed. Both open circuit voltage (Voc) and short circuit current (Isc) found boosted enhancing the power conversion efficiency (%) from 0.065% to 0.28% at x=0.1. The flat band potentials (Vfb) were also determined for these cells and it is found to attain a maximum value at x=0.1. The other cell parameters were estimated and showed improvement in the overall performance of a cell. Attempts were made to explain the observed results through modified electrode properties. 相似文献
992.
Charanya G Patil KM Narayanamurthy VB Parivalavan R Visvanathan K 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》2004,218(6):431-443
This paper presents details of the study undertaken to find the effects of foot sole hardness, thickness and footwear on walking-foot pressure distribution parameters (power ratio (PR)) in diabetic neuropathy. The foot sole hardness is characterized by Shore level. PR represents the ratio of high-frequency power to the total power in the power spectrum of the walking-foot pressure image distribution obtained from the optical pedobarograph. Spatial frequency distributions in the walking-foot pressure images were analysed to calculate the PR in each of the foot sole areas at different levels of foot sole sensation loss and mechanical and geometrical properties. The results show that the increase in PR in the upper foot sole Shore ranges (30-40) is 1.2-2.5 times the corresponding increase in lower Shore ranges (20-30) for some foot sole areas, implying a higher possibility of development of plantar ulcers when combined with deterioration of foot sole sensation. Plantar ulcers are found in feet with foot sole Shore values of 30, a sensation level of 45 mN and PR of 35; for Shore values of 40, sensation levels of 100 mN, with PR 52; and for Shore values above 40, sensation level > 100 mN with PR 58. Providing microcellular rubber insole footwear based on optimum hardness and thickness was found to be helpful in healing plantar ulcers in three to four weeks. Wearing preventive footwear for six months reduced hardness of the foot sole and PR values to near-normal values. 相似文献
993.
Adolescent antecedents of high-risk driving behavior into young adulthood: substance use and parental influences 总被引:1,自引:0,他引:1
Driver history data, in combination with previously collected tenth-grade questionnaire data, for 4403 subjects were analyzed by Poisson regression models to identify the significant substance use and parental characteristics predicting subsequent high-risk driving of new drivers (starting at age 16) through age 23-24 years. Substance use (cigarettes, marijuana, and alcohol) reported at age 15 was shown to be an important predictor of subsequent excess risk of serious offenses and serious crashes for both men and women. In addition, negative parental influences (lenient attitudes toward young people's drinking; low monitoring, nurturance, family connectedness), were also demonstrated to increase the risk of serious offenses and serious crashes for both men and women. 相似文献
994.
Arun Kumar Singh Chauhan Vinay Gupta K. Sreenivas 《Materials Science and Engineering: B》2006,130(1-3):81-88
Synthesis of Ca doped PbTiO3 powder by a chemically derived sol–gel process is described. Crystallization characteristics of different compositions Pb1−xCaxTiO3 (PCT) with varying calcium (Ca) content in the range x = 0–0.45 has been investigated by DTA/TGA, X-ray diffraction and scanning electron microscopy. The crystallization temperature is found to decrease with increasing calcium content. X-ray diffraction reveals a tetragonal structure for PCT compositions with x ≤ 0.35, and a cubic structure for x = 0.45. Dielectric properties on sintered ceramics prepared with fine sol–gel derived powders have been measured. The dielectric constant is found to increase with increasing Ca content, and the dielectric loss decreases continuously. Sol–gel derived Pb1−xCaxTiO3 ceramics with x = 0.45 after poling exhibit infinite electromechanical anisotropy (kt/kp) with a high d33 = 80 pC/N, ′ = 298 and low dielectric loss (tan δ = 0.0041). 相似文献
995.
Liquid phase acylation of benzene by acyl chloride (e.g., benzoyl chloride, butyryl chloride or phenyl acetyl chloride) over InCl3, GaCl3 and ZnCl2 supported on commercial clays (viz. montmorillonite-K10, montmorillonite-KSF and kaolin) or high silica mesoporous MCM-41 at 80°C has been investigated. The Mont.-K10 and Si-MCM-41 supported InCl3 and GaCl3 catalysts showed high activity in the acyation of benzene by benzoyl chloride even in the presence of moisture in the reaction mixture. The redox function of the supported InCl3, GaCl3 or ZnCl2 catalysts seems to play a very important role in the acylation process. 相似文献
996.
Arun Sharma Suman Chakraborty 《International Journal of Heat and Mass Transfer》2008,51(19-20):4875-4885
Analytical solutions are obtained for the temperature and Nusselt number distribution in the thermal entrance region of a parallel plate microchannel under the combined action of pressure-driven and electroosmotic transport mechanisms, by taking into account the effects of viscous dissipation, Joule heating and axial conduction simultaneously, in the framework of an extended Graetz problem. Step changes in wall temperature are considered to represent physically conceivable thermal entrance conditions. The solution of the temperature distributions at the various channel sections essentially involves the determination of a set of eigenvalues and eigenfunctions corresponding to a Sturm Liouiville problem with non self-adjoint operators. The resultant eigenfunctions are non orthogonal in nature, and are obtained in the forms of hypergeometric functions. Parametric variations on the effects of the relative strengths of the pressure gradients and the electric field, ratio of the rate of heat generation to the rate of wall heat transfer, and the Peclet number are analyzed in details, in terms of their influences on the temperature field as well as the Nusselt number distribution. 相似文献
997.
Properties of spray deposited titanium dioxide thin films and their application in photoelectrocatalysis 总被引:1,自引:0,他引:1
P.S. Shinde S.B. Sadale P.S. Patil P.N. Bhosale A. Brüger M. Neumann-Spallart C.H. Bhosale 《Solar Energy Materials & Solar Cells》2008,92(3):283-290
Thin films of titanium dioxide were deposited onto optically transparent, electrically conducting substrates (fluorine doped tin oxide on glass). The two oxide layers, SnO2 and TiO2, were deposited sequentially by spray pyrolysis. TiO2 films of up to 800 nm thickness were prepared by varying the quantity of sprayed solution (titanyl acetylacetonate in methanol), at a growth rate of 0.15 nm/s.The effect of film thickness on the structural, optical and photoelectrochemical properties of TiO2 films was studied. Scanning electron microscopy showed that the polycrystalline anatase films were compact. The grain size increased up to 1100 nm with increase in film thickness, whereas the crystallite size remained constant (40 nm) as shown by X-ray diffraction. The films had a transmittance of more than 70% in the visible region.Junctions of the semiconducting films with aqueous electrolytes were rectifying and photoactive. Films of 330 or 600 nm were thick enough to exhibit maximum photoelectrochemical response for light of a wavelength of 313 or 365 nm, respectively. Under depletion conditions, an IPCE (incident photon to current conversion efficiency) of 0.8 for a 330 nm thick film at 313 nm was obtained.Oxalic acid degradation under UVA light and under sunlight, applying electrical bias, was demonstrated using these electrodes. 相似文献
998.
Vibhor Jain Basanta Kumar Rajbongshi Arun Tej Mallajosyula Gitalee Bhattacharjya S Sundar Kumar Iyer Gurunath Ramanathan 《Solar Energy Materials & Solar Cells》2008,92(9):1043-1046
Organic solar cells were fabricated with two new imidazolin-5-one molecules as active layers. The use of imidazolin-5-ones, derivatives of a biomolecule chromophore, for photovoltaic applications is particularly attractive due to its biodegradable nature and tunable properties. Single-layer devices with two analogues of imidazolin-5-ones were prepared and characterized. Devices fabricated with one of the molecules as the active layer showed a maximum Jsc of 0.52 μA cm−2 and Voc of 0.68 V at an incident power of 20.32 mW cm−2, while the other set of devices showed a maximum Jsc of 0.63 μA cm−2 and Voc of 0.57 V at the same incident power. 相似文献
999.
P. S. Patil P. R. Patil S. S. Kamble S. H. Pawar 《Solar Energy Materials & Solar Cells》2000,60(2):143-153
Tungsten oxide (WO3) thin films are prepared by using a simple and inexpensive solution thermolysis technique. Thin film samples of different thickness are obtained by varying quantity of ammonium tungstate solution sprayed onto the preheated conducting glass substrate. A simple three-electrode cell has been formed to study the electrochemical and electrochromic properties. The electrochemical parameters of the cell such as anodic peak current, anodic peak potential, threshold voltage, amount of H+ ions intercalated into and deintercalated out of the WO3 samples are calculated. The effect of film thickness on these parameters are studied. The extent of electrochromism and reversibility of the colouration/bleaching processes of various WO3 samples are described. The colouration efficiencies at 633 nm are calculated. The maximum colouration efficiency obtained for thicker film, is 56 cm2/C. The samples were found to be stable in 0.05N H2SO4 electrolyte up to 1×103 colour/bleach cycles. 相似文献
1000.
A. N. Patil M. G. Patil K. K. Patankar V. L. Mathe R. P. Mahajan S. A. Patil 《Bulletin of Materials Science》2000,23(5):447-452
The dielectric properties (dielectric constant and loss) for the system Cu
x
Fe3−x
O4 with x = 1.0, 0.8, 0.6, 0.4 and 0.2, were studied in the temperature range 300 ∼ 800 K and also in the frequency range 1
kHz ∼ 1 MHz. A.c. conductivity was derived from dielectric constant and loss tangent data. The conduction in this system is
interpreted as due to small polaron hopping. The dielectric relaxation was observed for the compositions with tetragonal structure
whereas normal behaviour was observed for cubic structure. 相似文献