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Separation of Eu(Ⅲ) with supported dispersion liquid membrane system containing D2EHPA as carrier and HNO_3 solution as stripping solution

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Journal of Rare Earths 2011年第1期29卷 7-14页

作者：裴亮王理明于国强 Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences School of Environment and Chemistry Engineering Xi'an Polytechnic University Faculty of Water Resources and Hydraulic Power Xi'an University of Technology

The Eu（III） separation in supported dispersion liquid membrane （SDLM）, with polyvinylidene fluoride membrane （PVDF） as the support and dispersion solution containing HNO3 solution as the stripping solution and Di（2-ethylhexyl） phosphoric acid （D2EHPA） dis- solved in kerosene as the membrane solution, was studied. The effects ofpH value, initial concentration of Eu（III） and different ionic strengths in the feed phase, volume ratio of membrane solution and stripping solution, concentration of HNO3 solution, concentration of carrier, different stripping agents in the dispersion phase on the separation of Eu（III） were also investigated, respectively. As a result, the optimum separation conditions of Eu（III） were obtained as the concentration of HNO3 solution was 4.00 mol/L, concentration of D2EHPA was 0.160 mol/L, and volume ratio of membrane solution to stripping solution was 30：30 in the dispersion phase, and pH value was 5.00 in the feed phase. Ionic strength had no obvious effect on the separation of Eu（III）. Under the optimum conditions studied, when initial concentration of Eu（III） was 1.00× 10^-4 mol/L, the separation rate of Eu（III） was up to 94.2% during the separation period of 35 min. The kinetic equation was developed in terms of the law of mass diffusion and the theory of interface chemistry. The results were in good agreement with the literature data.

关键词： supported dispersion liquid membrane Di(2-ethylhexyl) phosphoric acid europium(III) dispersion phase separation flux separation rate

Mating behavior induces changes of expression of Fos protein,plasma testosterone and androgen receptors in the accessory olfactory bulb (AOB) of the male mandarin vole Microtus mandarinus

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Current Zoology 2009年第4期55卷 288-295页

作者： Fengqin HE Fadao TAI College of Life sciences Shaanxi Normal University Xi＇an 710062 China Department of Life sciences Xi＇an University of Arts and Science Xi＇an 710065 China

In order to investigate the neuroendocrine mechanism of the mating behavior in the adult male mandarin voles Microtus mandarinus,the radioimmunoassay(RIA)and immunohistochemistry methods were used to investigate the differences in plasma testosterone(T)concentrations and distribution of T immunoreactive neurons(T-IRs),androgen receptor immunoreactive neurons(AR-IRs)and Fos protein immunoreactive neurons(Fos-IRs)in the accessory olfactory bulb(AOB)and the main olfactory bulb(MOB)following exposure to clean hard-wood shavings(control group),soiled bedding(exposure group)or contact with an estrous female(mating group).Results showed that plasma T concentration was significantly higher in the mating group than that in the exposure group,and both the mating group and the exposure group displayed significantly higher plasma T concentration than the control group.T-IRs,AR-IRs and Fos-IRs were investigated with the immunohistochemistry method in granule cell(GC)and mitral cell(MC)of the MOB and the AOB in the three *** were significantly more T-IRs,AR-IRs and Fos-IRs in MC and GC of the AOB in the mating group than that in the exposure group or the control group.T-IRs,AR-IRs and Fos-IRs did not show significant differences between the exposure group and the control ***,obvious differences in MC and GC of the MOB were not found among the three *** results confirm that both changes of T and AR in the AOB might be underlying mating behavior in the adult male mandarin voles.

关键词：野鼠类荷尔蒙 RIA 动物学

Channel Correlation Analysis by Exploiting Temporal-Spectral-Spatial Information

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Chinese Journal of Electronics 2015年第2期24卷 379-387页

作者： PANG Lihua ZHANG Yang LI Jiandong LIANG xiao WANG Qiaofeng LIU xilin School of Information Engineering Xi'an University of Science and Technology State Key Laboratory of Integrated Service Networks Xidian University National Mobile Communications Research Laboratory Southeast University Wireless Product Operation ZTE Corporation

This paper deals with the modeling, analysis, and measurement of a Small scale fading(SSF) mobile radio channel. The physics of SSF are first reviewed to reveal the generating mechanisms of channel selectivity.A stochastic channel model is then derived as a function of time, antenna array displacement and frequency, which falls in the category of tapped delay line model. Specifically,the taps can be represented as a combination of a possible line of sight or dominant reflected path and a Gaussian distributed component comprised of unresolvable scattered paths. After that, general analytical solutions are provided for the 3D temporal-spectral-spatial correlations of SSF via the exploitation of channel statistical properties. We show that this function can be expressed as the product of three low order temporal, spectral and spatial correlations individually under appropriate assumptions on the associated wireless propagation environment. This will definitely facilitate the derivations of the closed form expression regarding the correlation function of SSF. From engineering perspective, this analysis can be utilized to develop network correlation maps for example. Finally, out field measurement results verify the validity of our theoretical analysis.

关键词： Channel correlation Small scale fading Channel measurement Multipath propagation Parameter extraction

A new localization theory of adaptive machining of near-net-shape blades

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Chinese Journal of Aeronautics 2021年第6期34卷 18-32页

作者： Neng WAN xiaogang SHEN Zhiyong CHANG Zezhong C.CHEN Department of Mechanical Engineering Northwestern Polytechnical UniversityXi'an 710072China Department of Mechanical Industrial and Aerospace EngineeringConcordia UniversityMontrealQuebec H3G IMSCanada

In the fabrication of aero-engine blades,a great deal is gained when massive material removal is avoided at the end of the process,and as little as possible material is left on the blade *** to the uncertainty of pre-process,the billet shapes are ***,the near-net-shape billet doesn’t cover the blade design surface to be ***,blade localization is necessary for these billets before the *** conventional localization methods,the design surface’s location focused on guaranteeing enough material to be ***,because the to-becut surface is in near-net and free-form shape,it is difficult to find a valid localized surface model to generate the tool *** from the localized surface is taken as rigid in previous investigation,it is allowed to deviate from the design surface no more than the tolerance *** term of this principle,the tolerance band is utilized to promote localization ability.A series of optimization models with different priorities is established to avoid the abandonment expensive blade ***,with the experiments performed on the near-net-shape blades,the blade localization theory and the promotion of localization ability are verified.

关键词： Blade localization Curvature constraint Machining surface Near-net-shape blade Tolerance constraint

Microstructure and properties of ductile iron bars for plunger pump prepared by horizontal continuous casting process

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China Foundry 2019年第2期16卷 118-125页

作者： Chun-jie Xu Zhen Zhao Yu Lei Yong-hui Liu Zhong-ming Zhang Yan Li Dan Shechtman School of Materials science and Engineering Xi'an University of Technology xi'an Shechtman Nobel Prize New Materials Institute Shaanxi Huaan Continuous Casting Co. Ltd. Faculty of Materials science and Engineering Technion-Israel Insititue of Technology

Ductile iron bars(DIBs) with a diameter of 145 mm, used for plunger pump production, were made by the horizontal continuous casting(HCC). The microstructure of the samples cut at three locations with different distances away from the surface(~20 mm from the surface, half of the radius and the center of the HCCDIBs)were investigated. The mechanical properties were measured by tensile and torsion tests. Results show that after the spheroidization of graphite, the iron matrix incorporates the nodules of Format I, Size 8 close to the surface, Format I, Size 7 at the half of the radius from the surface, and Format II, Size 6 in the centre of the bar,according to the ASTM A247 standard. The content of pearlite in the matrix changes from 55%(~20 mm from the surface) to 70%(half of the radius) and 80%(the center of the HCCDIBs). The strengths in tension are 552, 607 and 486 MPa with the elongations of 12.5%, 10.5% and 5.8% in samples cut at these three locations from the surface to the centre, respectively. The strength in torsion is equal to 558, 551 and 471 MPa at corresponding torsion angles of 418°, 384° and 144° respectively to the same distance from the bar surface. Fracture in tension is manifested via crack propagation through the interface between graphite nodules and matrix(Mode I), while in torsion the fracture is caused by the shear of graphite nodules(Mode II). It is shown that the transition between two fracture modes is also dependent on the size of graphite nodule. Typically, fracture Mode I was observed for nodules of smaller diameter(less than 22.7 μm) and fracture Mode II was seen for nodules of greater diameter(more than 24.8 μm).

关键词： horizontal continuous casting ductile iron bars plunger pump tension and torsion properties microstructure

Deformation behaviors of four-layered U-shaped metallic bellows in hydroforming

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Chinese Journal of Aeronautics 2020年第12期33卷 3479-3494页

作者： Jing LIU Zhiyong LV Yang LIU Lanyun LI Key Laboratory of Materials Processing Engineering School of Material Science and EngineeringXi'an Shiyou UniversityXi'an 710065China Key Laboratory of Advanced Manufacture technology for Automobile Parts(Chongqing University of technology) Ministry of EducationChongqing 400054China Bime Bremen Institute of Mechanical EngineeringMAPEX Center for Materials and ProcessingUniversity of BremenBremen 28359Germany

Because of the complex constraint effects among layers in multi-layered metallic bellows hydroforming,the stress concentration and defects such as wrinkling and fracture may easily *** is a key to reveal the deformation behaviors in order to obtain a sound *** on the ABAQUS platform,a 3 D-FE model of the four-layered U-shaped metallic bellow hydroforming process is established and validated by *** stress and strain distributions,wall thickness variations and bellow profiles of each layer in the whole process,including bulging,folding and springback stages,are *** deformation behaviors of bellows under different forming conditions are *** is found that the wall thinning degrees of different layer vary after hydroforming,and is the largest for the inner layer and smallest for the outer *** folding stage,the wall thinning degree of the crown point increases lineally,and the difference among layers increases as the process *** displacements of the crown point decrease from the inner layer to the outer *** springback,the U-shaped cross section changes to a tongue shape,the change of convolution pitch is much larger than the change of convolution height,and the springback values of the inner layer are smaller than the outer *** increase in the internal pressure and die spacing cause the maximum wall thinning degree and springback *** changing of process parameters,bellows with deep convolution are easily encountered wall thinning during hydroforming and convolution distortion after *** research is helpful for precision forming of multi-layered bellows.

关键词： Deformation behaviors Four-layered U-shaped bellow Hydroforming Numerical simulation Springback

Propagation of shaped beam through uniaxially anisotropic chiral slab

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Chinese Physics B 2020年第11期29卷 380-385页

作者：王明军张佳琳张华永王梓涵 School of Automation and Information Engineering Xi’an University of TechnologyXi’an 710048China School of Electronics and Information Engineering Anhui UniversityHefei 230039China School of Chemistry and Chemical Engineering Anhui UniversityHefei 230039China School of Physics and Telecommunications Engineering Shaanxi University of TechnologyHanzhong 723001China

A general solution is obtained to a canonical problem of the reflection and refraction of an arbitrary shaped beam by using a uniaxially anisotropic chiral *** reflected,internal as well as refracted shaped beams are expanded in terms of cylindrical vector wave functions,and the expansion coefficients are determined by using the boundary conditions and method of moments *** two typical examples,the normalized field intensity distributions are evaluated for a fundamental Gaussian beam and Hermite-Gaussian beam,and some propagation properties,especially the negative refraction phenomenon,are discussed briefly.

关键词： shaped beam uniaxially anisotropic chiral slab reflection and refraction negative refraction phenomenon

Preparation and Characterization of Waterborne Polyurethane/Cellulose Nanocrystal Composite Membrane from Recycling Waste Paper

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Journal of Renewable Materials 2020年第6期8卷 631-645页

作者： xing Zhou xin Zhang Dong Wang Changqing Fang Wanqing Lei Zhigang Huang Yonghua Song xinyu He Yingwei Huang Faculty of Printing Packaging Engineering and Digital Media TechnologyXi’an University of TechnologyXi’an710048China School of Materials science and Mechanical Engineering Beijing Technology and Business UniversityBeijing100048China

Cellulose plays a key role in abundant organic natural materials meeting the increasing demand for green and biocompatible *** highly crystalline nanoscale component of cellulose nanocrystals has recently attracted great attention due to the versatile performance as filler or matrix in producing functional *** this work,we prepared the waterborne polyurethane via a prepolymer process,and obtained cellulose and cellulose nanocrystals from waste paper via a facile acid hydrolysis *** that,the cellulose nanocrystals were assembled into film and mixed with polyurethane to prepare flexible polyurethane/cellulose nanocrystals composite membrane with different soaking *** correlation between the bulk structure and applied properties including thermal resistance and mechanical property was investigated by using Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM),thermogravimetric analysis(TGA),differential scanning calorimetry(DSC)and folding *** structure analysis indicates that cellulose nanocrystals prepared from used paper have a quality similar to that of commercial ***,the cellulose nanocrystals have been mixed with polyurethane *** can significantly benefit to the thermal resistance and mechanical property of the cellulose nanocrystals *** polyurethane/cellulose nanocrystals composite membrane present good flexibility and may hold a significantly potential application as visual and flexible material.

关键词： Cellulose waterborne polyurethane membrane recycling

Effect of Cu content on microstructure and mechanical properties of in-situ β phases reinforced Ti/Zr-based bulk metallic glass matrix composite by selective laser melting(SLM)

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Journal of Materials science & technology 2021年第8期67卷 174-185页

作者： Xuehao Gao xin Lin Qiaodan Yan Zihong Wang xiaobin Yu Yinghui Zhou Yunlong Hu Weidong Huang State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an710072China Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design MUT ChinaNorthwestern Polytechnical UniversityXi'an710072China

In this study,non-toxic in-situβphases of reinforced Ti/Zr-based bulk metallic glass matrix composites(BMGCs)of(Ti_(0.65)Zr_(0.35))100-xCux(x=5,10,15 at.%)are fabricated via selective laser *** effect of Cu content on phase formation,microstructure,and mechanical properties is *** average volume fraction and width of theβphase decreases with increasing Cu content,while a more amorphous phase and the(Ti,Zr)_(2)Cu phase *** the center zone of the molten pool,theβphase grows in the direction of the temperature gradient,and the amorphous phase distributes among theβ*** occurs using:sphere morphology(for x=5),a more continuous elongated sphere and network morphology(for x=10),and network morphology(for x=15),*** the edge zone of the molten pool,due to the smaller cooling rate and the existence of a partially molten zone,theβphase becomes coarser,and an amorphous phase forms for more continuous ***,the hardness improves significantly with increasing Cu *** crack is found for x=*** the average volume fraction of theβphase for x=5 is about 90%,the compression yield strength is 1386±64 MPa,reaching to an average level of conventionally fabricated counterparts,due to finer microstructure,and twinning and martensitic transformation of theβphase.

关键词： Metallic glass Amorphous phase βPhase Bulk metallic glass matrix composites(BMGCs) Additive manufacturing(AM) Selective laser melting(SLM)