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1.
Sodium alginate was graft-copolymerized with ethyl acrylate using ceric ammonium nitrate as an initiator. In order to optimize the conditions for grafting, the concentrations of nitric acid, initiator and monomer together with temperature, time and amount of substrate were varied. The kinetic scheme of free radical graft copolymerization has been proposed and the equations relating the values of rate of polymerization, rate of graft copolymerization and rate of homopolymerization are also suggested. The experimental results agree very well with the proposed kinetic scheme. 相似文献
2.
Aman Singh Jaydip Chandrakant Mehta Divya Anand Pinku Nath Babita Pandey Aditya Khamparia 《Expert Systems》2021,38(1)
In real world, the automatic detection of liver disease is a challenging problem among medical practitioners. The intent of this work is to propose an intelligent hybrid approach for the diagnosis of hepatitis disease. The diagnosis is performed with the combination of k‐means clustering and improved ensemble‐driven learning. To avoid clinical experience and to reduce the evaluation time, ensemble learning is deployed, which constructs a set of hypotheses by using multiple learners to solve a liver disease problem. The performance analysis of the proposed integrated hybrid system is compared in terms of accuracy, true positive rate, precision, f‐measure, kappa statistic, mean absolute error, and root mean squared error. Simulation results showed that the enhanced k‐means clustering and improved ensemble learning with enhanced adaptive boosting, bagged decision tree, and J48 decision tree‐based intelligent hybrid approach achieved better prediction outcomes than other existing individual and integrated methods. 相似文献
3.
Chandrakant Parlikar Md Zafir Alam Dipak K. Das 《Transactions of the Indian Institute of Metals》2014,67(2):203-208
The effect of prior oxidation, for various durations up to 2,000 h in air at 650 °C, on the room temperature tensile properties of uncoated and Al3Ti diffusion aluminide coated near α Ti alloy, Titan 29A, has been evaluated. The tensile properties of the uncoated alloy deteriorated with oxidation. Oxidation for just 100 h caused 11–13 % decrease in yield strength (YS) and ultimate tensile strength (UTS) of the alloy. The uncoated alloy exhibited brittle fracture within the elastic regime at significantly lower stress after oxidation for 2,000 h. On the other hand, the strength of the coated alloy remained unaffected even after 2,000 h of oxidation and the YS and UTS was similar to that of the un-oxidized alloy. The ductility of the coated alloy, however, decreased with the increase in oxidation duration. Such differences in the tensile behavior of the uncoated and coated alloy can be ascribed to the beneficial effect of the Al3Ti diffusion aluminide coating in preventing surface embrittlement in the alloy during oxidation. 相似文献
4.
A two-dimensional, mesoscale model of the atmosphere that incorporates hydrodynamic, thermodynamic, and microphysical processes has been applied to simulate the impact on regional weather of a solar thermal electric conversion (STEC) installation in southern Spain. The STEC plant is conceptualized to occupy an area of 1,000 km2 with heliostats covering 25 per cent of the total power plant area. It is assumed to use wet natural draft cooling towers for dissipating waste heat into the atmosphere.The 2-D model is applied to a STEC facility that covers a distance of 32 km in the horizontal with heliostats installed in the middle over a distance of 8 km. The model has been integrated for 9 hr of real time for both typical summer and winter conditions.The results of integration for summer indicate that a STEC installation of the above size has considerable potential for modifying regional weather. Clouds formed after 5 hr of real-time integration and persisted until the end of the integration; rainfall also occurred. In contrast, clouds did not form until 7 hr of real-time integration without the installation and were more sporadic and transient; rainfall was much less.The results for winter conditions do not show any cloud formation after 9 hr of real-time integration. This difference between summer and winter cases is attributed to the very strong winds used as initial conditions for the winter simulation. 相似文献
5.
Parlikar T.A. Chang W.S. Qiu Y.H. Seeman M.D. Perreault D.J. Kassakian J.G. Keim T.A. 《Mechatronics, IEEE/ASME Transactions on》2005,10(5):482-494
In conventional internal combustion engines, engine valve displacements are fixed relative to crankshaft position. If these valves were actuated as a variable function of crankshaft angle, significant improvements in fuel economy could be achieved. To this end, a new type of electromagnetic valve drive system (EMVD) for internal combustion engines was more recently proposed. This EMVD incorporates a disk cam with a very desirable nonlinear profile which that functions as a nonlinear mechanical transformer. Modeling and simulation results showed significant advantages of this EMVD over previously designed electromagnetic engine valve drives. In this articles, we describe an experimental implementation of the proposed EMVD, which was developed to confirm these benefits. The EMVD apparatus was designed, constructed, and integrated into a computer-controlled experimental test stand. The experimental results confirm the benefits of using a nonlinear mechanical transformer in a motordriven engine-valve spring system, as seen in the small average power consumption and low valve seating velocity. In addition, a valve transition time sufficient for 6000-rpm engine operation was achieved. The results also suggest ways to improve the EMVD apparatus in the future. 相似文献
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7.
Jerzy Kujawski Chandrakant S. Desai Czeslaw Miedzialowski 《Computers & Structures》1989,32(6):1319-1323
Inelastic dynamic response of building walls made of reinforced concrete is considered by using various explicit and implicit algorithms. The numerical examples show the computational efficiency of algorithms for different low and high walls. 相似文献
8.
Sagar M. Mane Pravin M. Tirmali Snehal L. Kadam Dadasaheb J. Salunkhe Chandrakant B. Kolekar 《应用陶瓷进展》2017,116(6):325-332
0.5[(Ba0.7Ca0.3)TiO3]–0.5[Ba(Zr0.2Ti0.8)O3] lead-free ceramics were synthesised by coprecipitation method and sintered by fast microwave sintering (MWS) and by conventional sintering (CS) at 1200°C. After being sintered with the two different methods, the materials were characterised for structural, microstructural, frequency and temperature-dependent dielectric properties, Raman spectroscopy, and ferroelectric measurements. Results are compared and discussed in the present paper. X-ray diffraction confirms the presence of the tetragonal and rhombohedral phases in the composites sintered by both methods. The ferroelectric to paraelectric transition temperature (Tc) is increased in microwave-sintered composite. Diffuse constant (γ) values show BCT–BZT ceramics to be neither normal ferroelectrics nor relaxor ferroelectrics. Raman spectra confirm phase transition in the ceramic samples. Saturation polarisation (Ps) values are 7.62 and 4.28?µC?cm?2 and nearly equal remanant polarisation (Pr) values were observed for BCT–BZT composite sintered with MWS and CS, respectively. 相似文献
9.
Pragati A. Shinde Vaibhav C. Lokhande Amar M. Patil Taeksoo Ji Chandrakant D. Lokhande 《International Journal of Hydrogen Energy》2018,43(5):2869-2880
In present study, new strategy is employed to build composite nanostructure and asymmetric configuration to enhance the capacitive performance of supercapacitor device. The WO3-MnO2 composite with mesoporous structure is prepared by single-step hydrothermal method and used to gain superior electrochemical performance in asymmetric configuration. A binder-free and additive-less WO3-MnO2 composite electrode exhibits high specific capacitance of 609 F g?1 at a scan rate of 5 mV s?1. The flexible asymmetric supercapacitor device with WO3-MnO2 as a positive electrode and WO3 as a negative electrode demonstrates stable operating potential window of 1.4 V with specific capacitance of 103 F g?1 at a scan rate of 5 mV s?1 and energy density of 24.13 Wh kg?1 at power density of 915 W kg?1. Furthermore, WO3-MnO2//WO3 device exhibits good cycle life with capacity retention of 95% after 2500 cycles and excellent mechanical flexibility. These results reveal the potential of WO3-MnO2 composite electrode for fabrication of high-performance supercapacitors. 相似文献
10.
Chandrakant V. Sharma J. R. Trivedi S. K. Chaudhury 《Transactions of the Indian Institute of Metals》2017,70(10):2651-2660
Recovery of Mn in steel making process depends on various processing parameters such as temperature, flow rate ratio of oxygen and argon gas in AOD process, carbon content, slag basicity, and V-ratio, Si content etc. The effect of these process parameters on Mn recovery in Mn-based stainless steel production is studied and optimized to maximize Mn recovery. It is observed that highest Mn recovery is achieved when slag basicity is maintained in the range of 1.7–1.8 and V-ratio is kept at 1.5. Further, it is noted that at high temperature, recovery of Mn is less because loss of Mn due to oxidation increases exponentially with the increase in temperature. Maximum Mn recovery is observed at 1585 °C bath temperature. Reduction of MnO with coke forms CO2 gas and free Mn in the melt. To maximize recovery of Mn in stainless steel, it is of paramount importance that oxidation of Mn is reduced and reduction of MnO is accelerated. Oxidation of Mn is minimized by reducing the flow rate of oxygen and reduction of MnO is accelerated by adding adequate amount of coke to the molten charge. 相似文献