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Mudanjiang, China

Zhu Y.-R.,Anhui University of Technology | Yin L.-C.,Mudanjiang Normal College | Yi T.-F.,Anhui University of Technology | Liu H.,Harbin Institute of Technology | And 2 more authors.
Journal of Alloys and Compounds | Year: 2013

Submicron-sized Li4Ti5O12 anode was synthesized through a two-step solid-state reaction. The relationship between the structural properties, electrochemical performance discharged to 0 V and lithium-ion intercalation kinetics was discussed using the experiments as well as the first-principles calculations. Structural analyses reveal that Li 4Ti5O12 synthesized by the two-step solid-state method has high phase purity. Scanning electron microscopy (SEM) shows that Li4Ti5O12 has a homogeneous size distribution in the range of 0.4-0.6 μm. The initial discharge capacity of Li 4Ti5O12 is 234.6 mA h g-1 at 0.5 C rate between 0 and 2.5 V, and it is close to the theoretical capacity value. The high structure stability of Li4Ti5O12 is related to the strong covalent bonding characteristic between Ti and O according to the first-principles calculation. Electrochemical impedance spectroscopy (EIS) indicates that the charge transfer resistance of the Li4Ti 5O12/Li cell evidently decreases with increasing of the temperature, and the apparent activation energies of Li4Ti 5O12 electrode on the lithium diffusion process and the charge transfer are calculated to be 19.05 and 22.48 kJ mol-1, respectively. © 2012 Elsevier B.V. All rights reserved. Source

Cai X.,Mudanjiang Normal College
Acta Crystallographica Section E: Structure Reports Online | Year: 2011

In the centrosymmetric binuclear title compound, [Ni2(C 15H8O7)2(H2O) 6], the NiII ion is in a distorted octahedral coordination geometry with O6 donors, three from three water molecules, the others from three carboxylate groups of two ligands. Extensive O-H⋯ ⋯ ⋯O hydrogen bonding connects the molecules into a three-dimensional supramolecular structure. Source

Xu H.,Mudanjiang Normal College
Applied Mechanics and Materials | Year: 2011

In this paper, a novel class of Cohen-Grossberg neural networks with inverse Hö lder neuron activation functions is presented. By employing the Brouwer degree properties and linear matrix inequality techniques, the existence and uniqueness of equilibrium point for such Cohen-Grossberg neural networks are investigated. By constructing appropriate Lyapunov functions and using Lyapunov diagonally stable matrices, a sufficient condition which is used to checked the global exponential stability of a unique equilibrium point is established. A numerical example is given to demonstrate the effectiveness of the theoretical results. © (2011) Trans Tech Publications, Switzerland. Source

Wang H.,Mudanjiang Normal College
Advanced Materials Research | Year: 2011

This paper discusses the development of "Double-qualified" teachers, and put forward several proposals to draw on the existing experience. They are the study in the German dual system, the teachers' access system, the training mode, the assessment mechanism, and the circumstances to construct double-qualified teaching staff and so on. This work has important significance to cultivate high-quality teacher and meet the urgent need of higher vocational schools. © (2011) Trans Tech Publications, Switzerland. Source

Zheng Y.,Mudanjiang Normal College
Applied Mechanics and Materials | Year: 2012

In this paper, a new dopant of P3N5 (phosphorus nitride) was doped into the diamond growth cell to grow diamond crystals by temperature gradient growth method (TGM) under high pressure and high temperature (HPHT). The experiments were performed at a fixed pressure of about 6.0 GPa and temperatures of 1600-1650 K. The gained diamond crystals were characterized by infrared (IR) absorption spectroscopy, micro-Raman spectroscopy and X-ray photoelectron spectroscopy (XPS), respectively. IR measurements demonstrated that, nitrogen atom was indeed doped into diamond crystals, and the diamond crystals with perfect shape containing nitrogen concentration ranging from 461 atomic parts per million (ppm) to 2186 atomic ppm were successfully synthesized. Nitrogen atoms present in diamond crystal were predominantly in isolated form accompanied by a small amount of nitrogen pairs. Micro-Raman spectra implied that crystalline quality deteriorated with nitrogen concentration gradually increased in diamond-growing environment. The XPS spectra revealed that only a few of phosphorus impurities about tens of ppm level were incorporated into a diamond crystal which was heavily doped with P3N5. This study will promote the application of doping diamonds in micro-electronics field and other fields. © (2012) Trans Tech Publications, Switzerland. Source

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