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排序方式: 共有410条查询结果,搜索用时 12 毫秒
21.
C Prabhakar G Madhusudhan K Sahadev CM Reddy MR Sarma GO Reddy R Chakrabarti CS Rao TD Kumar R Rajagopalan 《Canadian Metallurgical Quarterly》1998,8(19):2725-2730
Novel compounds having a dual pharmacophore were synthesised and evaluated for their insulin sensitiser and anti-inflammatory properties in different animal models. 相似文献
22.
J. B. Belavadi N. Rajagopalan P. S. Desikan U. Sen 《Journal of Applied Electrochemistry》1982,12(5):501-503
The four-component magnesium cell electrolyte containing MgCl2, CaCl2, NaCl and KCl has been converted to a quasi-ternary system by keeping the proportion of NaCl and KCl in the mixture equimolecular. The triangular phase diagram has been drawn depicting the fusibility isotherms of the system. It has been possible to obtain complete liquid mixtures at temperatures as low as 400° C by suitably adjusting the proportions of the four components of the molten salt mixture. 相似文献
23.
Experimental studies of particle deposition from liquid suspensions of monodispersed particles flowing past single spherical collectors were carried out and compared with theoretical results based on trajectory calculations. The experimental observations indicate the significant effect of particle flocculation and thus suggest the importance of sedimentation as a collection mechanism. The agreement between the theoretical results and the experimental data is good when the surface force interactions are favorable for collection. However, when the electrokinetic repulsion dominates in the neighborhood of the collector, the rate of collection drops rapidly, although not to zero as predicted by theory. 相似文献
24.
25.
Rajagopalan S. Aller J. M. Restrepo J. A. Habetler T. G. Harley R. G. 《Industry Applications, IEEE Transactions on》2006,42(6):1464-1477
There are several applications where the motor is operating in continuous nonstationary operating conditions. Actuators and servo motors in the aerospace and transportation industries are examples of this kind of operation. Detection of faults in such applications is, however, challenging because of the need for complex signal processing techniques. Two novel methods using windowed Fourier ridges and Wigner-Ville-based distributions are proposed for the detection of rotor faults in brushless dc motors operating under continuous nonstationarity. Experimental results are presented to validate the concepts and illustrate the ability of the proposed algorithms to track and identify rotor faults. The proposed algorithms are also implemented on a digital signal processor to study their usefulness for commercial implementation 相似文献
26.
Silicon - Non liner optical single crystals of bis(thiourea) lead chloride (BTLC), belonging to the semi-organic material category, have been prepared by a slow solvent evaporation process. The... 相似文献
27.
Devendrasinh Darbar M.R. Anilkumar Vijayaraghavan Rajagopalan Indranil Bhattacharya Hendry Izaac Elim T. Ramakrishnappa F.I. Ezema Rajan Jose M.V. Reddy 《Ceramics International》2018,44(5):4630-4639
Optimization of electrodes for charge storage with appropriate processing conditions places significant challenges in the developments for high performance charge storage devices. In this article, metal cobaltite spinels of formula MCo2O4 (where M = Mn, Zn, Fe, Ni and Co) are synthesized by oxalate decomposition method followed by calcination at three typical temperatures, viz. 350, 550, and 750 °C and examined their performance variation when used as anodes in lithium ion batteries. Phase and structure of the materials are studied by powder x-ray diffraction (XRD) technique. Single phase MnCo2O4,ZnCo2O4 and Co3O4 are obtained for all different temperatures 350 °C, 550 °C and 750 °C; whereas FeCo2O4 and NiCo2O4 contained their constituent binary phases even after repeated calcination. Morphologies of the materials are studied via scanning electron microscopy (SEM): needle-shaped particles of MnCo2O4 and ZnCo2O4, submicron sized particles of FeCo2O4 and agglomerated submicron particle of NiCo2O4 are observed. Galvanostatic cycling has been conducted in the voltage range 0.005–3.0 V vs. Li at a current density of 60 mA g?1 up to 50 cycles to study their Li storage capabilities. Highest observed charge capacities are: MnCo2O4 – 365 mA h g?1 (750 °C); ZnCo2O4 – 516 mA h g?1 (550 °C); FeCo2O4 – 480 mA h g?1 (550 °C); NiCo2O4 – 384 mA h g?1 (750 °C); and Co3O4 – 675 mA h g?1 (350 °C). The Co3O4 showed the highest reversible capacity of 675 mA h g?1; the NiO present in NiCo2O4 acts as a buffer layer that results in improved cycling stability; the ZnCo2O4 with long needle-like shows good cycling stability. 相似文献
28.
A structural study on MFCl (M=Ca, Sr, Ba) and BaFX (X=Br, I) 总被引:1,自引:0,他引:1
G Kalpana B Palanivel K Venkatasubramaniam M Rajagopalan 《Bulletin of Materials Science》1997,20(4):461-465
Here we present the electronic band structure calculations of CaFCl, SrFCl, BaFCl, BaFBr and BaFI performed using tight binding
linear muffin-tin orbital method. The calculated ground state properties namely the lattice parameters, bulk moduli and the
pressure-volume relations were found to be in good agreement with the experimental values. The electronic band structure of
these compounds were calculated at ambient as well as in the high pressure region. The band gap values of these insulating
systems were calculated and compared with available experimental values. At high pressure these compounds exhibit the interesting
phenomenon of band overlap metallization. 相似文献
29.
30.
A methodology is presented for the minimum cost optimization of prestressed concrete solid and voided slabs. Apart from the rationale imparted to the design process, the method is shown to yield considerable savings in prestressing steel and therefore savings in energy. Computer programs developed for the implementation of the methodology have facilitated the speedy running of the procedure a myriad of times over a wide range of design parameters such as span, live load, material and erection cost ratios, concrete and strand strengths, prestress effectiveness etc. Qualitative and quantitative conclusions regarding the behavioural characteristics of the parameters and the manner of their interplay in the optimal picture are advanced. 相似文献