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91.
The synthesis of series of dysprosium-doped lithium manganese oxide in the general formula LiDy x Mn2?x O4 (x?=?0.0, 0.05, 0.1, 0.15, and 0.2) using double stage coprecipitation method followed by microwave heat treatment is reported. The characterization results of X-ray diffraction and infrared spectroscopy have illustrated the cubic structure for all the compounds. The lattice parameter has been observed to decrease with dysprosium doping. The influence of doping in elastic property of the samples has been studied with infrared spectroscopy. The grain size of the LiDy0.05Mn1.95O4 has been observed to be less than 1???m. The Image J software has been used to further analyze the micrographs. The initial capacity of the samples are observed to decrease with Dy3+ doping, but the capacity retention after 50 cycles for Dy 0.05, 0.1, 0.15, and 0.2 samples are reported as 95.4%, 93.2%, 91.3%, and 87.7%, respectively. The electrochemical impedance spectra has been performed to analyze the effectiveness of Dy3+ ion doping and the act of Dy doping has been observed to reduce the charge transfer resistance and increase the Li ion diffusion coefficient. 相似文献
92.
Cecchet F Lis D Caudano Y Mani AA Peremans A Champagne B Guthmuller J 《J Phys Condens Matter》2012,24(12):124110
93.
Using pyronin B and crystal violet dye mixture, the characteristics of energy transfer distributed feedback dye laser (ETDFDL) pumped by 532 nm Nd:YAG laser were investigated. The characteristics of donor DFDL and acceptor DFDL as well as the dependence of their pulse widths and output powers on pump power and acceptor concentrations were studied. The output energy of DFDL was measured at the emission peaks of donor and acceptor dyes for different pump powers and acceptor concentrations, and tunability was observed from 570 to 645 nm using prism dye cell arrangement. 相似文献
94.
Abbati Maria Cristina Manià Alessandro Provenzi Edoardo 《Letters in Mathematical Physics》2001,57(1):69-81
We construct the loop transform in the case of Abelian gauge theories as a unitary operator given by the inductive limit of Fourier transforms on tori. We also show that its range, i.e. the space of kinematical states of the quantum loop representation, is the Hilbert space of square integrable complex valued functions on the group of hoops. 相似文献
95.
96.
Active health monitoring in a rotating cracked shaft using active magnetic bearings as force actuators 总被引:1,自引:0,他引:1
We consider the active health monitoring of rotordynamic systems in the presence of breathing shaft cracks. The shaft is assumed to be supported by conventional bearings and an active magnetic bearing (AMB) is used in a mid-shaft or outboard location as an actuator to apply specified, time-dependent forcing on the system. These forces, if properly chosen, induce a combination resonance that can be used to identify the magnitude of the time-dependent stiffness arising from the breathing mode of the shaft crack. 相似文献
97.
We consider a group of automorphisms of a compact convex set X. Using simplical measure techniques we find a decomposition of points of X into “G-primary” points. The decomposition of Guichardet and Kastler for quasi-invariant states of a separable C1- algebra is generalized. 相似文献
98.
Vimal Chandra Srivastava Indra Deo Mall Indra Mani Mishra 《Colloids and surfaces. A, Physicochemical and engineering aspects》2008,312(2-3):172-184
The present study reports the competitive adsorptive removal of cadmium (Cd(II)) and zinc (Zn(II)) ions from binary systems using rice husk ash (RHA), a waste obtained from the rice husk-fired furnaces, as an adsorbent. The initial pH (pH0) affects significantly the capacity of RHA for adsorbing the metallic ions in the aqueous solution. The pH0 ≈ 6.0 is found to be the optimum for the removal of Cd(II) and Zn(II) ions by RHA. The single ion equilibrium adsorption from the binary solution is better represented by the non-competitive Redlich–Peterson (R–P) and the Freundlich models than by Langmuir model in the initial metal concentration range of 10–100 mg/l. The adsorption of Zn(II) ion is more than that of Cd(II) ion, and this trend is in agreement with the single-component adsorption data. The equilibrium metal removal decreases with increasing concentrations of the other metal ion and the combined effect of Cd(II) and Zn(II) ions on RHA is generally found to be antagonistic. Non-modified Langmuir, modified Langmuir, extended-Langmuir, extended-Freundlich, Sheindorf–Rebuhn–Sheintuch (SRS), non-modified R–P and modified R–P adsorption models were tested to find the most appropriate competitive adsorption isotherm for the binary adsorption of Cd(II) and Zn(II) ions onto RHA by minimizing the Marquardt's percent standard deviation (MPSD) error function. The extended-Freundlich model satisfactorily represents the adsorption equilibrium data of Cd(II) and Zn(II) ions onto RHA. 相似文献
99.
N. Nair M. R. A. Pillai R. S. Mani S. Naik M. Desai P. Upadhye M. P. Colaco 《Journal of Radioanalytical and Nuclear Chemistry》1988,122(1):129-135
A single reagent radioimmunoassay for thyroxine in blood samples absorbed on filter paper for the mass screening of neonatal hypothyroidism is described. Blood samples were collected by pricking the heel of newborn babies (3 days old) and pressing Whatman 3 filter paper against the wound. 6 mm diameter blood spots were punched out at the time of assay and incubated with 0.4 ml of a preincubated antigen-antibody complex for six hours at 37 °C. 1 ml of 22% polyethylene glycol is used for the precipitation of antigen-antibody complex. The assay has a sensitivity of 2.2 ng/ml. 500 samples collected from newborns were analyzed in the assay and gave a mean of 117.6±31.9 ng/ml. 相似文献
100.
Raj Gandhi Subhendra Mohanty Tarun Souradeep S Agarwalla K Bhattacharya B Brahmachari R Crittenden S Goswami P Ghoshal M Lindner H S Mani S Mitra S Pascoli S Panda R Rangarajan S Ray T Roy Choudhury R Saha S Sarkar A Srivastava R Sheth S Uma Sankar U Yajnik 《Pramana》2006,67(4):735-742
The working group on astroparticle and neutrino physics at WHEPP-9 covered a wide range of topics. The main topics were neutrino
physics at INO, neutrino astronomy and recent constraints on dark energy coming from cosmological observations of large scale
structure and CMB anisotropy. 相似文献