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991.
DongJie Guo HaiTao Ding Haiju Wei Qingsong He Min Yu ZhenDong Dai 《中国科学E辑(英文版)》2009,52(10):3061-3070
This paper reports a new technique to fabricate an ion-exchange polymer-metal composite (IPMC) actuator. This technique is based on a hybrid organic-inorganic composite membrane. In the fabrication course, silica oxide particles, prepared from hydrolysis of tetraethyl orthosilicate in situ with sol-gel reaction, co-crystallize with perfluorosulfonate acid (PFSA) ionomer. Attenuated total reflectance fourier transform infrared spectroscopy (ATR-FTIR) analyses demonstrate that a highly water-saving hybrid mem... 相似文献
992.
Andre SULPICE Jean-Louis SOUBEYROUX Christophe VERWAERDE Gia Ky HOANG 《中国科学E辑(英文版)》2009,52(10):3071-3075
Two sets of internal-Sn Nb3Sn superconducting strands were fabricated through RRP method, one with 2 wt% of Ti alloyed in Sn core and the other just pure Sn. Four reaction temperatures of 650℃, 675℃, 700℃ and 725℃ and 128 h duration were applied for A15 phase formation heat treatment after Cu-Sn alloying procedure of 210℃/50 h + 340℃/25 h. For the heat-treated coil samples, transport non-Cu JC was examined through standard 4-probe technique and phase microstructure was observed by means of Field Emission Sc... 相似文献
993.
In order to restrain the mid-spatial frequency error in magnetorheological finishing (MRF) process, a novel part-random path is designed based on the theory of maximum entropy method (MEM). Using KDMRF-1000F polishing machine, one flat work piece (98 mm in diameter) is polished. The mid-spatial frequency error in the region using part-random path is much lower than that by using common raster path. After one MRF iteration (7.46 min), peak-to-valley (PV) is 0.062 wave (1 wave =632.8 nm), root-mean-square (RM... 相似文献
994.
Research on indoor experimentation of range SAL imaging system 总被引:1,自引:0,他引:1
GUO Liang XING MengDao ZHANG Long TANG Yu & BAO Zheng State Key Laboratory of Radar Signal Processing Xidian University Xi’an China Xi’an Polytechnic University Xi’an 《中国科学E辑(英文版)》2009,52(10):3098-3104
By means of advantages of both SAR and lidar, the combination of the techniques of (inverse) synthetic aperture and lidar makes it possible to obtain high resolution 2-D image. In this paper, an indoor experimental system of inverse synthetic aperture lidar imaging is given and a processing approach is presented. The given system is in the mode of lidar system with separated receiver and transmitter, which can effectively eliminate the jamming from the lens or/and the intersection between two optic fibers. ... 相似文献
995.
YUAN Jing HE ZhengJia ZI YanYang & LIU Han State Key Laboratory for Manufacturing Systems Engineering School of Mechanical Engineering Xi’an Jiaotong University Xi’an China Shanghai Baosteel Industry Inspection Corporation Baosteel Group Corporation Shanghai 《中国科学E辑(英文版)》2009,52(10):2801-2809
Fault diagnosis of rolling mills, especially the main drive gearbox, is of great importance to the high quality products and long-term safe operation. However, the useful fault information is usually submerged in heavy background noise under the severe condition. Thereby, a novel method based on multiwavelet sliding window neighboring coefficient denoising and optimal blind deconvolution is proposed for gearbox fault diagnosis in rolling mills. The emerging multiwavelets can seize the important signal proce... 相似文献
996.
ZhenXia Wang XinNian Li CuiLan Ren ZhenZhong Yong JianKang Zhu WenYun Luo XiaoMing Fang 《中国科学E辑(英文版)》2009,52(11):3215-3218
The experimental investigations on the interaction between Ag-nanocrystal particles (Ag-NCPs) and carbon nanotubes (CNTs)
in Ag-nanocrystal particles/carbon nanotubes (Ag-NCPs/CNTs) hybrid structures were reported. The growth of Ag-NCPs on multiwalled
carbon nanotubes (MWCNTs) was carried out by thermal evaporation deposition. High-resolution transmission electron microscopy
and X-ray diffraction analyses revealed that Ag-NCPs had the crystal lattice feature of face-centered cube (fcc). The growth
of Ag-NCPs on MWCNTs induced the cross-section deformation of MWCNT. The experimental results also showed that the synthesized
Ag-NCPs/CNTs hybrid structure appeared as quasi-one dimensional nanowires containing the Ag-NCP/CNT hetero-junction. There
was local cross-section deformation on MWCNTs at the interface of hetero-junction. These results involve the important topic
about fundamental and practical studies for structure of MNCPs on CNTs and also find clues to further research of Ag nanocrystal
growing on MWCNTs and related Ag-CNT interaction. 相似文献
997.
JuYing Wu ChengXi Zhou QingWen Zhu EnRong Li Ge Dai Long Ba YuHong Huang Jun Mei 《中国科学E辑(英文版)》2009,52(12):3497-3503
The ruthenium oxide nanoparticles with size less than 20 nm were fabricated by annealing the metallic ruthenium nanoparticles
in air, which were synthesized by using the thermal reduction in the polyol solution. The rutile structure of the ruthenium
oxide was proved by using transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The oxide has
good electron conductivity. The surface of the ruthenium oxide was modified by a vinyl silane coupling agent. The assembling
of the silane to the oxide surface was proved by Infrared (IR) absorption spectroscopy. By mixing the nanoparticles with poly(methylvinylsiloxane)
(PMVS) silicone rubber, a composite filled with dispersive conducting phase was fabricated. The temperature dependent conductivity
shows that the electron transportation through composite is mainly dominated by tunneling. The measurement of piezoresistance
shows that the composite at low strain has high piezoresistance repeatability. The 3D reconstruction images of the composite
filled with carbon black or ruthenium oxide show that the aggregation of the nanoparticles differs much for two composites.
The narrow distribution range of the particle size was thought to be the main factor for the high piezoresistance recurrence. 相似文献
998.
This paper presents a physically-based integrated hydrologic model that can simulate the rainfall-induced 2D surface water
flow, 3D variably saturated subsurface flow, upland soil erosion and transport, and contaminant transport in the surface-subsurface
system of a watershed. The model couples surface and subsurface flows based on the assumption of continuity conditions of
pressure head and exchange flux at the ground, considering infiltration and evapotranspiration. The upland rill/interrill
soil erosion and transport are simulated using a non-equilibrium transport model. Contaminant transport in the integrated
surface and subsurface domains is simulated using advection-diffusion equations with mass changes due to sediment sorption
and desorption and exchanges between two domains due to infiltration, diffusion, and bed change. The model requires no special
treatments at the interface of upland areas and streams and is suitable for wetland areas and agricultural watersheds with
shallow streams. 相似文献
999.
Irrigation practices greatly affect sustainable agriculture development. In this study, we investigated the effects of irrigation
efficiency on water flow and chemical transport in soils, which had significant impact on the environment. Field dye staining
experiments were conducted at different soils with various irrigation amount. Image analysis was conducted to study the heterogeneous
flow patterns and their relationships with the irrigation efficiency. Irrigation efficiency and its environmental effects
were evaluated using various indictors, including application efficiency, deep percolation ratio, storage efficiency, and
uniformity. Under the same irrigation condition, soil chemical distributions were more heterogeneous than soil water distributions.
The distributions were mainly affected by soil texture, initial soil water content, and irrigation amount. Storage efficiency,
irrigation uniformity, and deep percolation ratio increased with irrigation amount. Since the chemical distribution uniformity
was lower than the water uniformity, the amount of chemical leaching increased sharply with decrease of irrigation uniformity,
which resulted in high environmental risks of groundwater pollution. 相似文献
1000.
Earth pressure balance control for EPB shield 总被引:1,自引:0,他引:1
This paper mainly deals with the critical technology of earth pressure balance (EPB) control in shield tunneling. On the assumption that the conditioned soil in the working chamber of the shield is plasticized, a theoretical principle for EPB control is proposed. Dynamic equilibrium of intake volume and discharge volume generated by thrust and discharge is modeled theoretically to simulate the earth pressure variation during excavating. The thrust system and the screw conveyor system for earth pressure cont... 相似文献