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41.
Commercialization of Li–S in present scenario is obstructed by poor performance of cathode and its compatibility with electrolyte used. Here in this work, in order to improve the electrochemical performance all solid state Li–S battery, solid electrolyte (SE) formed by composition of lithium sulfide (Li2S) and phosphorus pentasulfide (P2S5) combinedly called LPS is used. The modified carbon in the form of graphene oxide (GO) and reduced graphene oxide (rGO) as additive is used to provide better electron conduction pathway. High conductivity of the order 10−4 S cm−1 of prepared LPS overcomes the major drawback of insulating nature of sulfur. The coin cells are fabricated by using above mentioned material as a cathode material, LPS as SE, and lithium foil as anode. The prepared nanocomposites are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) to study structural and morphological properties. Energy dispersive X-ray spectroscopy (EDS) images of the cathode surface confirms the uniform spreading of material. The electrochemical performance of coin cell is studied by Galvanostatic charge-discharge plot at 0.1 C to check the compatibility of composite and electrolyte prepared. The cells having additive material GO and rGO with host sulfur show better results as compared to the cell having pristine sulfur.  相似文献   
42.
X-ray absorption spectroscopy studies of the polycrystalline SrRu0.5Mn0.5O3 have been performed at Ru, Mn-L2,3 edges. The 2p-->t2g related peak at the Ru-L2 edge is more intense than the Ru-L3 edge and a shift of the 2p-->eg related peak by approximately 0.8 eV to higher energy than that of the Ru(IV) compound, SrRuO3 is observed. In combination with a crystal field multiplet calculation approach, a possible anomalous change in the spectral features is explained based on the existence of a redox ionic pair involving Ru(IV)/Ru(v)<-->Mn(III)/Mn(IV).  相似文献   
43.
We demonstrate a cladding-pumped single-mode plane-polarized ytterbium-doped fiber laser generating 633 W of continuous-wave output power at 1.1 microm with 67% slope efficiency and a polarization extinction ratio better than 16 dB. The laser is end pumped through both fiber ends and shows no evidence of roll-over, even at the highest output power, which is limited only by the available pump power.  相似文献   
44.
We present a single-frequency, single-mode, plane-polarized ytterbium-doped all-fiber master oscillator power amplifier source at 1060 nm generating 264 W of continuous-wave output power. The final-stage amplifier operated with a high gain of 19 dB and a high conversion efficiency of 68%. There was no evidence of rollover from stimulated Brillouin scattering even at the highest output power, and the maximum output was limited only by the available pump power.  相似文献   
45.
We have constructed a class of plane symmetric macro models in Barber's second self-creation theory, when the source of the gravitational field is a macro matter field representing perfect fluid and satisfying the gamma-law equation of state p=(-1), where =4/3 and 3/2. The solutions of the field equations are derived and their physical aspects are studied.  相似文献   
46.
In this article, the novel (G /G)-expansion method is successfully applied to construct the abundant travelling wave solutions to the KdV–mKdV equation with the aid of symbolic computation. This equation is one of the most popular equation in soliton physics and appear in many practical scenarios like thermal pulse, wave propagation of bound particle, etc. The method is reliable and useful, and gives more general exact travelling wave solutions than the existing methods. The solutions obtained are in the form of hyperbolic, trigonometric and rational functions including solitary, singular and periodic solutions which have many potential applications in physical science and engineering. Many of these solutions are new and some have already been constructed. Additionally, the constraint conditions, for the existence of the solutions are also listed.  相似文献   
47.
We investigate certain classes of normal completely positive (CP) maps on the hyperfinite II1 factorA. Using the representation theory of a suitable irrational rotation algebra, we propose some computable invariants for such CP maps. Dedicated to Professor K B Sinha  相似文献   
48.
P. K. Sahu  N. Otuka  M. Isse  Y. Nara  A. Ohnishi 《Pramana》2006,66(5):809-816
We analyze the spectra of pions and protons in heavy-ion collisions at relativistic energies from 2 A GeV to 65+65 A GeV by using a jet-implemented hadron-string cascade model. In this energy region, hadron transverse mass spectra first show softening until SPS energies, and re-hardening may emerge at RHIC energies. Since hadronic matter is expected to show only softening at higher energy densities, this re-hardening of spectra can be interpreted as a good signature of the quark-gluon plasma formation  相似文献   
49.
Influence of radiation dose in the range of 0.5–2.0 MGy of60Co -rays on the isothermal decomposition of sodium bromate at 633.0 K shows that irradiation increases the initial gas evolution {ie37-1}, shortens the induction period (I), enhances the rate of reaction in the accelerating and decay stages. The data fit well the Prout-Tompkins relationship, indicating that nucleation occurs in a chain branching manner during the process. The fraction decomposed, , increases with increasing radiation dose.  相似文献   
50.
The structural phase transition and electronic properties at ambient (B 1-phase) and high pressure (B 2-phase) of heavy rare earth monoantimonides (RESb; RE?=?Ho, Er, and Tm) have been studied theoretically using the self-consistent tight binding linear muffin tin orbital method. These compounds show metallic behavior under ambient condition and undergo a structural phase transition to the B 2 phase at high pressure. We predict a structural phase transition from the B 1 to B 2 phase in the pressure range 30.0–35.0?GPa. Apart from this, the ground state properties, such as lattice parameter and bulk modulus are calculated and compared with the available theoretical and experimental results.  相似文献   
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