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61.
Savita Khare Priti Shrivastava Rajendra Chokhare Jagat Singh Kirar Swati Parashar 《Journal of Porous Materials》2017,24(4):855-866
Metal–salen intercalated α-zirconium phosphate, abbreviated as {α-ZrP·M(Salen), where M = Fe(III) and Mn(II)} was synthesized insitu by the flexible ligand method. The structure of resulting compounds was characterized by BET surface area, powder X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray analysis, X-ray photoelectron spectroscopy, thermogravimetric analysis and UV–visible spectroscopy. The catalytic activity of α-ZrP·M(Salen) was tested for the oxidation of cyclohexane using dry tert-butylhydroperoxide as an oxidant. In the oxidation reaction, cyclohexane was oxidized to cyclohexanol (A), cyclohexanone (K) and some unidentified products. It was found that the reactivity of α-ZrP·Fe(Salen) is greater than α-ZrP·Mn(Salen) in the oxidation reaction. Influence of various reaction parameters viz. reaction temperature, catalyst concentration, substrate to oxidant molar ratio was studied using α-ZrP·Fe(Salen) catalyst to obtain maximum conversion (29.30%) of cyclohexane. The catalyst was reused for five cycles without significant loss of catalytic activity. 相似文献
62.
Swanand M. Bhagwat 《传热工程》2013,34(18):1485-1494
The specific objective of this work is to develop an empirical model to predict the existence of stratified flow in horizontal and downward inclined gas-liquid two-phase flow. The proposed model is in nondimensional form and attempts to emulate the qualitative trend of the Taitel and Dukler mechanistic model. The key advantage of the proposed method is that it is explicit in nature and, unlike Taitel and Dukler, it does not require use of a graphical or iterative solution. The empirical parameters used in the proposed model account for the effect of pipe diameter, pipe orientation, and the liquid density on the transition line between stratified and nonstratified flow. The accuracy of the proposed model is verified against the flow visualization data collected from more than 16 data sources consisting of 8 fluid combinations, pipe diameter in a range of 8.9 to 300 mm, liquid density in a range of 780 to 1420 kg/m3, and all downward pipe inclinations including horizontal. 相似文献
63.
Various design criteria have been set for Rotating Biological Contactor (RBC) for treating urinal wastewater. The aim of treating urinal wastewater is to remove odour and color from it so that it can be recycled for flushing. In the present paper, significance of RBC system for treating urinal wastewater has also been elaborated. The setting up of design criteria is based on the assumption that the rate of nitrification is zero-order with respect to total Kjeldhal nitrogen concentration. Principles of bioprocess involved in wastewater treatment have also been described in relation to the composition of human urine. 相似文献
64.
Malagi Archana Vadiraj Das Chandan J. Khare Kedar Calamante Fernando Mehndiratta Amit 《Magma (New York, N.Y.)》2019,32(5):519-527
Magnetic Resonance Materials in Physics, Biology and Medicine - To investigate the effect of number and combination of b values used on the accuracy of estimated Intravoxel Incoherent Motion (IVIM)... 相似文献
65.
In the present paper charging and discharging transient currents in polyvinyl formal (PVF) were measured as a function of
temperatures (40–80°C), poling fields (90 ×103−9.0 × 104 V/cm) and electrode combinations (Al-Al, Au-Al, Zn-Al, Bi-Al, Cu-Al and Ag-Al). The current-time characteristics have different
values of slope lying between 0.42–0.56 and 1.42–1.63. The polarization is considered to be due to dipolar reorientation associated
with structural motions and space charge relaxations due to trapping of injected charge carriers in energetically distributed
traps. 相似文献
66.
H.S. Khare 《Polymer》2010,51(3):719-9825
The materials science community has identified nanoparticle dispersion as a primary challenge area for the advancement of polymer nanocomposites technology. Although nanoparticle dispersion can significantly impact important engineering properties, it is not itself a quantifiable property; qualitative TEM image assessments remain as the ‘gold standard’ for dispersion characterization. While numerous quantitative dispersion analyses have been proposed, they have often proven cumbersome, system specific and unreflective of the proposed benefits of nanoparticle reinforcement. No single quantitative method has been adopted by the community to date and inferences about processing and dispersion effects generally require subjective analysis. This paper presents a quantitative dispersion characterization method which 1) makes use of standard TEM dispersion images; 2) directly reflects proposed nanoscale reinforcement mechanisms; 3) outputs a single performance metric. By quantitatively isolating dispersion effects, this technique may help to link disparate studies in the literature while providing defensible quantitative insights into nanoscale reinforcement mechanisms. 相似文献
67.
In present investigation, chemometric tools, principal component analysis (PCA) and Hierarchical clustering analysis (HCA) are used to get the linkage between the coal properties and kinetics of pyrolysis. Thermo gravimetric analysis (TGA) of 10 perhydrous Indian coals was done. Devolatilization of these coals showed five independent reactions. Kinetic parameters were calculated for individual reaction. Activation energy and weight loss of each reaction has been analyzed as a function of coal properties (moisture, volatile matter, ash, fixed carbon, carbon, hydrogen, nitrogen and sulfur). By applying chemometric, was extracted information about the linkage between activation energies of each reaction and coal properties. The mathematical treatment of data has provided conclusions on properties of coal and kinetic parameters. 相似文献
68.
Multimedia Tools and Applications - In this study, we present a method for human activity recognition in video sequences. Human activities are often described by a holistic feature vector... 相似文献
69.
M. Kumar G. K. Gupta O. P. Modi B. K. Prasad A. K. Khare M. Sharma 《Canadian Metallurgical Quarterly》2017,56(1):58-66
The present work compares the properties of the Cu–TiB2 composites prepared by varying the mechanical milling conditions. The Cu–TiB2 composites were processed using Cu–TiB2 powders combined milling, a powder mixture consisting of separately milled Cu & TiB2 and a powder mixture prepared by the combination of separate and combined milling. The hardness and flexural strength of the combined milled powders were found to be maximum, despite of their lower sintered density. The separately milled powders achieved excellent electrical properties combined with moderate hardness and flexural strength. The properties of composites processed using the combination of separate and combined milling laid in between the two conditions of combined and separate milling. 相似文献
70.
U. Bhunia J. Pradhan A. Roy V. Khare U. Panda A. De S. Bandopadhaya T. Bhattacharyya S. Thakur M. Das S. Saha C. Mallik R.K. Bhandari 《低温学》2012,52(12):719-724
Our centre has taken up a project of development of superconducting magnetic energy storage (SMES) technology to have better power quality for its accelerator program. In the first phase, a prototype cryostable coil has been designed, fabricated and commissioned in a standard bath cryostat. The various parameters of the magnet coil have been determined in order to maximize stored energy taking into consideration the constraints like geometry, maximum current limit etc. Winding tension (Pre-stress) of 13.6 MPa is maintained to keep radial stress compressive in all possible scenarios (i.e. during cool-down, excitation, etc.). Mylar is used for turn to turn insulation while 1 mm thick glass epoxy based picket fences (G-10) are placed symmetrically azimuthally for layer to layer insulation as well as to ensure passage of liquid helium inside the winding.Cryostability of the conductor implies more copper to superconductor ratio and is desired as far as stability of the coil is concerned. Cryostability, however may degrade when helium vapor is trapped in between two layers. Therefore, quench behavior of the magnet along with protection system has also been studied and implemented. This paper describes issues related to design study, fabrication and also cryogenic test results of the coil. 相似文献