Silver nanoparticles were prepared by pulsed wire discharge (PWD) using silver wire in deionized water at various relative energy (K) from 10 to 98, which is ratio of the charged energy of the capacitor in the electri...
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Silver nanoparticles were prepared by pulsed wire discharge (PWD) using silver wire in deionized water at various relative energy (K) from 10 to 98, which is ratio of the charged energy of the capacitor in the electrical circuit to the vaporization energy of the wire. From energy deposition calculated by the measured voltage and current waveforms, deposited energy of the wire was increased with increasing K. From X-ray diffraction (XRD) analysis, prepared nanoparticles were phase identified as silver. From transmission electron microscopy observations, the shape of prepared silver nanoparticles were spherical and the median particle diameter (D50) and the geometric standard deviation (σg) were calculated from the particle distribution. D50 was decreased from 34 to 19 nm with increasing K. The particle size in prepared by PWD in liquid media can be controlled by K.
Highly oriented titanate nanotube (TNT) film was successfully synthesized by a simple electrophoretic deposition (EPD) method without any hard templates and surfactants. This oriented films adequately utilized the exc...
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Highly oriented titanate nanotube (TNT) film was successfully synthesized by a simple electrophoretic deposition (EPD) method without any hard templates and surfactants. This oriented films adequately utilized the excellent properties of ID nanomaterials such as single crystal semiconductor architectures, large surface area, and superior charge transport, which lead to higher photocatalytic activity. We believe that this versatile method can be extent to fabricate other ordered ID nanomaterials films. [ABSTRACT FROM AUTHOR]
Recently, indoor positioning technology based on received signal strength in wireless networks are becoming more and more attractive. In this paper, we firstly introduced the experimental testbed in a typical office b...
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Recently, indoor positioning technology based on received signal strength in wireless networks are becoming more and more attractive. In this paper, we firstly introduced the experimental testbed in a typical office building. Then, we proposed the mechanism to improve the positioning accuracy by using five different filtering methods because of harsh multi-path environment and all kinds of disturbance in indoor areas. Thirdly, the experimental parameters of five filtering methods, called Limit Filter, Threshold Filter, Max Filter, MA Filter and Kalman Filter, were optimized and analyzed. Finally, we summarized the five filtering methods, and compared the performance of Limit Filter, Threshold Filter and Max Filter in detail. Experimental results demonstrated that the proposed Limit Filter andThreshold Filter can increase the accuracy in 3 meters of 91% to 98%.
A novel method based on radio frequency magnetron sputtering tailored to the deposition of low residual stress and adherent c-BN thin films on silicon substrates was developed. In this study, the effect of noble gas (...
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A novel method based on radio frequency magnetron sputtering tailored to the deposition of low residual stress and adherent c-BN thin films on silicon substrates was developed. In this study, the effect of noble gas (Kr, Ar, Ne and He) added in Ar gas during sputtering on the residual stress and the c-BN content has been investigated. As a result, it was found that the residual stress of c-BN thin film decreased with increasing the helium gas flow rate within argon gas.
A novel indoor positioning system based on received signal strength (RSS) in wireless networks with high accuracy is presented in this paper. The three improvement mechanisms, called signal strength filter, user locat...
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A novel indoor positioning system based on received signal strength (RSS) in wireless networks with high accuracy is presented in this paper. The three improvement mechanisms, called signal strength filter, user location filter and path tracking assistance, are employed to improve the positioning accuracy of the system. The comprehensive performance of the proposed system is analyzed in detail and compared with the Radar system. Experimental results demonstrate that the proposed system in this paper can improve 80% accuracy in 3 meters of Radar system to 93% in typical office building testbed. Therefore, the indoor positioning system presented in this paper has the advantages of high accuracy, low cost and easy expansibility, and it can be used to locate people and assets in the fields of logistics, healthcare, and manufacturing.
A research focus on semi-solid metal processing is the preparation of semi-solid slurry with non-dendritic microstructure. During the past several decades, people tended to obtain the non-dendritic structure by stirri...
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In present paper a new niobate materials Ba5LixTixNb10-xO30 were synthesized by doping Li+ in the system BaO- TiO2- Nb2O5 in millimeter wave field. X-ray diffraction (XRD) quantitative and scanning transition spectros...
In present paper a new niobate materials Ba5LixTixNb10-xO30 were synthesized by doping Li+ in the system BaO- TiO2- Nb2O5 in millimeter wave field. X-ray diffraction (XRD) quantitative and scanning transition spectroscopy (SEM) analysis were employed to study crystal structure and microstructure of reaction products. It was found that pure products could be obtained at temperature 900°, 8 min which is lower comparing with that by conventional method. The XRD data shown the crystal belongs to tetragonal tungsten bronze structure with space group P4bm. The grain size synthesized in millimeter wave field had smaller size, narrower distribution, better sinter-ability, and without hard agglomeration comparing whit that obtaining from conventional synthesis. At lower temperature Ba5LiTiNb9O30 is a tetragonal ferroelectric phase.
A high performance thermosetting epoxy resin crosslinkable at room temperature was obtained via directly moulding diglycidyl ether of bisphenol A（DGEBA） and flexibleα,ω-bisamino（n-alkylene）phenyl terminated poly...
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A high performance thermosetting epoxy resin crosslinkable at room temperature was obtained via directly moulding diglycidyl ether of bisphenol A（DGEBA） and flexibleα,ω-bisamino（n-alkylene）phenyl terminated poly（ethylene glycol）.The influences of the n-alkylene inserted in aminophenyl of flexible amino-terminated polythers（ATPE） on the mechanical properties,fractographs and curing kinetics of the ATPE-DGEBA cured products were *** results show that the insertion of n-alkylene group into the aminophenyl group of the ATPE,on one hand,can significantly increase the strain relaxation rate and decrease glass transition temperature of the ATPE-DGEBA cured products,resulting in slight decrease of the Young’s modulus and tensile strength,and significant increase of the toughness and elongation of the ATPE-DGEBA cured *** the other hand,it can remarkably enhance the reactivity of amine with epoxy,much accelerating the curing rate of the ATPE-DGEBA *** activation energy of DGEBA cured by BAPTPE,BAMPTPE and BAEPTPE was 53.1,28.5 and 25.4 kJ·mol;,*** as-obtained ATPE-DGEBA cured products are homogeneous, transparent,and show excellent mechanical properties including tensile strength and *** they are promising to have important applications in structure adhesives,casting bulk materials,functional coatings,cryogenic engineering, damping and sound absorbing materials.
作者：
Pan YongJun潘勇军Xie HongQuan陈勇Chen Yong崔丽College of Material Science and Engineering
Wuhan Textile University Wuhan 430074 China 武汉纺织大学材料科学与工程学院 武汉 430073 Department of Chemistry Huazhong University of Science and Technology Wuhan 430074China 武汉理工大学复合材料国家重点实验室 武汉 430070 State key laboratory of advanced technology for materials synthesis and processingWuhan University of Technology Wuhan 430070 China
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