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Sun G.F.,Nanjing Southeast University | Sun G.F.,Jiangsu University | Zhou R.,Jiangsu University | Zhang Y.K.,Nanjing Southeast University | And 4 more authors.
Optics and Laser Technology | Year: 2014

Wear resistant layers on nodular cast iron chains with C-B-W-Cr powders were fabricated by laser surface alloying (LSA). Microstructure, phases and lattice parameters, were investigated by means of optical microscopy, scanning electron microscopy, transmission electron microscopy and X-ray diffractometry. Micro-, nano-hardness and elastic modulus were measured with a Vickers microhardness tester and a nano-indendation tester. Lubricant sliding wear performance was performed on a ball-on-disk apparatus in ambient air using the straight line reciprocating wear form. Results indicate that microstructure of the alloyed layers changes from hyper-eutectic to hypo-eutectic, varing with laser specific energy. Nano-grain size and micro-hardness decrease while martensite lattice parameters increase with laser specific energy. Existence of graphite in the substrate increases the carbon content in the retained austenite to 1.59 wt%. Nano-hardness and elastic modulus of the alloyed layers are close. Friction and wear properties of the layers are improved by LSA compared with the substrate. Wear mechanism of them is illustrated. © 2014 Elsevier Ltd. Source


Zhang Y.,Chuzhou University | Deng J.,Chuzhou University | Wang J.,Chuzhou University | Wang Y.,Zilang Vocational Technical College | Ni S.,Chuzhou University
Zhongguo Xitu Xuebao/Journal of the Chinese Rare Earth Society | Year: 2012

The Yb3+/Er3+ co-doped Na(Y1.5Na0.5)F6 one dimensional nanorods were synthesized by a facile hydrothermal method. The X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence spectra were used to characterize the as-prepared samples. The cell parameter of the nanocrystals is a=b=0.600 nm, c=0.352 nm. Under 980 nm excitation, intense upconversion emissions from red to ultraviolet were observed. The red, green and near-ultraviolet emission bands were attributed to the 4F9/2→4I15/2, (2H11/2, 4S3/2)→4 I15/2 and (2G11/2/2 H9/2)→4I15/2 transition of Er3+, respectively. In terms of the experiment results, the upconversion mechanisms were also discussed. Source


Zhang Y.Y.,Chuzhou University | Wang Y.,Zilang Vocational Technical College | Deng J.Q.,Chuzhou University | Wang J.,Chuzhou University | Ni S.C.,Chuzhou University
Optics Communications | Year: 2014

Nanocrystals of up-conversion (UC) phosphor Yb3+/Tm3+ co-doped NaYF4 are prepared by a facile hydrothermal method using oleic acid as a stabilizing agent. The as-prepared nanocrystals are of hexagonal phase, and have tube-like morphology and strong ultraviolet (UV) and blue UC fluorescence intensity, which have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and luminescence spectroscopy. The effect of Yb3+ concentration on the UC emission properties is also analyzed. Our results reveal that the intensity of emission peaks can be controlled by varying the Yb3+ concentration and these NaYF 4 nanotubes are highly efficient host material. The as-prepared NaYF4 nanotubes show potential applications in UV compact solid state lasers and multi-channel fluorescent label. © 2013 Elsevier B.V. Source


Li Z.N.,Zilang Vocational Technical College | Zhou L.,Shanghai JiaoTong University
Advanced Materials Research | Year: 2013

In the paper, researched a fault diagnosis system which is used in the ICM (Intelligent Coiling Machine)successfully, it is a kind of fault diagnosis system that uses compactwavelet neural network wavelet neural network as the intelligent core and has the PFA(Principal Factor Analysis) pretreatment function. Through innovative designing and carefully plotted monitoring ways and methods in the system, as a result the fault diagnosis rate of accuracy is high, fault-tolerant ability is strong, the processing speed is quick, and the system work safely and reliably.It has achieved the anticipated goal and the effect. © (2013) Trans Tech Publications, Switzerland. Source


Li Z.N.,Zilang Vocational Technical College | Huang T.,Wuhan University of Technology
Applied Mechanics and Materials | Year: 2013

Using ultrahigh pressure of narrow vein reverse corona cracking method to generate high concentrations (electron density of 1011m-3 to1012 m-3) at low temperature (< 100 degrees C) plasma energy (energy 16 to 18 electron volts), purifying harmful ingredient of automobile tail gas on the automobile exhaust in the modern engineering, electrical, magnetic, optical, chemistry and other disciplines of the combination of research topic, also is the purification of automobile exhaust gas of a new idea, new method, new device, not only has very important academic value, but also has very important practical significance in engineering. This study has been made of high voltage pulse generator developed important level sex achievement. © (2013) Trans Tech Publications, Switzerland. Source

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