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A seven-crystal spectrometer for high-energy resolution X-ray spectroscopy at Shanghai Synchrotron Radiation Facility

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Nuclear Science and Techniques 2024年第9期35卷 82-91页

作者： Bing-Bao Mei liang-xin wang Song-Qi Gu Xiao-Zhi Su Shuo Zhang Yao Wei Jing-Yuan Ma Zheng Jiang Fei Song Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201800China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China

A Johann-type X-ray spectrometer was successfully developed at the hard X-ray branch(in-vacuum undulator with a 24-mm periodic length)of the energy material beamline(E-line)at the Shanghai Synchrotron Radiation Facility(SSRF).This spectrometer was utilized to implement X-ray emission spectroscopy(XES),high-energy resolution fluorescence-detected X-ray absorption spectroscopy(HERFD-XAS),and resonant inelastic X-ray *** spherically bent crystals were positioned on the respective vertical 500-mm-diameter Rowland circles,adopting an area detector to increase the solid angle to 1.75%of 4πsr,facilitating the study of low-concentrate systems under complex reaction *** under the atmosphere pressure,the spectrometer covers the energy region from 3.5 to 18 keV,with the Bragg angle ranging from 73°to 86°during vertical *** offers a promised energy resolution of sub-eV(XES)and super-eV(HERFD-XAS).Generally,these comprehensive core-level spectroscopy methods based on hard X-rays at the E-line with an extremely high photon flux can meet the crucial requirements of a green energy ***,they provide substantial support for scientific advances in fundamental research.

关键词： X-ray emission spectroscopy High-energy-resolution X-ray spectrometer Johann geometry Energy materials SSRF

Corrosion behaviors of zinc and Zn-Ni alloy compositionally modulated multilayer coatings

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Journal of University of Science and Technology Beijing 2005年第6期12卷 545-552页

作者： Jingyin Fei Guozheng liang Wenli xin Weikang wang Jianghong Liu Department of Applied Chemistry Northwestern Polytechnical University Xi＇an 710072 China

Zinc and Zn-Ni alloy compositionally modulated multilayer （CMM） coatings were electrodeposited from dual baths. The coated samples were evaluated in terms of surface appearance, surface and cross-sectional morphologies, as well as corrosion resistance. The results obtained from the salt spray test show that the zinc and Zn-Ni alloy CMM coatings are more corrosion-resistant than the monolithic coatings of zinc or Zn-Ni alloy alone with a similar thickness. The corrosion potential measurement and anodic polarisation tests were undertaken to examine the probable corrosion mechanisms of zinc and Zn-Ni alloy CMM coatings. Analysis on the micrographic features of zinc and Zn-Ni alloy CMM coatings after the corrosion test explains the probable reasons why the Zn-Ni/Zn CMM coatings have a better protective performance. Surface morphologies and compositional analysis of the remaining coating material of Zn-Ni alloy deposit after the corrosion test confirms the dezincification mechanism of the Zn-Ni alloy deposit during the corrosion process.

关键词： electrodeposition Zn-Ni alloy compositionally modulated multilayer coatings

Comparison of Characteristics of Sol-Gel and Precipitation Synthesis of Nanosized ZnO Powders

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稀有金属材料与工程 2006年第A3期35卷 506-507页

作者： Xiaoping liang Shaobo xin Xiaohui wang Yajin Liu Tianjin Municipal Key Lab of Fiber Modification and Functional Fiber Tianjin Polytechnic University Tianjin 300160 China

Zinc oxide nanosized powders with different sizes and morphologies were obtained by the sol-gel method and the precipitation method,*** effects of the sintering temperature on the characteristics of nanosized ZnO powders were *** particles were characterized by XRD and *** results show that the powders prepared by both methods are of hexagon crystalline,and the average diameter of the particles prepared by the sol-gel method is smaller than that by the precipitation method.

关键词： nanosized ZnO sol-gel precipitation

Revealing the Role of Defect in 3D Graphene-Based Photocatalytic Composite for Efficient Elimination of Antibiotic and Heavy Metal Combined Pollution

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Energy & Environmental Materials 2024年第3期7卷 164-174页

作者： xin wang Jingzhe Zhang Hui wang Mengjun liang Qiang wang Fuming Chen Research Institute of Frontier Science Southwest Jiaotong UniversityChengdu 610031China Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials School of Electronics and Information EngineeringSouth China Normal UniversityFoshan 528225China School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China Hubei Key Laboratory for High-Efficiency Utilization of Solar Energy and Operation Control of Energy Storage System Hubei University of TechnologyWuhan 430068China MOE Key Laboratory of Thermo-Fluid Science and Engineering School of Energy and Power EngineeringXi'an Jiaotong UniversityXi'an 710049China

Defect engineering can give birth to novel properties for adsorption and photocatalysis in the control of antibiotics and heavy metal combined pollution with photocatalytic ***,the role of defects and the process mechanism are complicated and ***,TiO_(2)/CN/3DC was fabricated and defects were introduced into the tripartite structure with separate O_(2)plasma treatment for the single *** find that defect engineering can improve the photocatalytic activity,attributing to the increase of the contribution from h^(+)and *** contrast to TiO_(2)/CN/3DC with a photocatalytic tetracycline removal rate of 75.2%,the removal rate of TC with D-TiO_(2)/CN/3DC has increased to 88.5%.Moreover,the reactive sites of tetracycline can be increased by adsorbing on the defective *** defect construction on TiO_(2)shows the advantages in tetracycline degradation and Cu^(2+)adsorption,but also suffers significant inhibition for the tetracycline degradation in a tetracycline/Cu^(2+)combined *** contrast,the defect construction on graphene can achieve the cooperative removal of tetracycline and Cu^(2+).These findings can provide new insights into water treatment strategies with defect engineering.

关键词： 3D graphene Cu defect photocatalytic composite tetracycline

DUSP2 deletion with CRISPR/Cas9 promotes Mauthner cell axonal regeneration at the early stage of zebrafish

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Neural Regeneration Research 2023年第3期18卷 577-581页

作者： Guo-Jian Shao xin-liang wang Mei-Li Wei Da-Long Ren Bing Hu School of Life Sciences Division of Biomedical SciencesUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina Anhui Province Key Laboratory of Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding College of Animal Science and TechnologyAnhui Agricultural UniversityHefeiAnhui ProvinceChina

Axon regeneration of central neurons is a complex process that is tightly regulated by multiple extrinsic and intrinsic *** expression levels of distinct genes are changed after central neural system(CNS)injury and affect axon regeneration.A previous study identified dusp2 as an upregulated gene in zebrafish with spinal cord ***,we found that dual specificity phosphatase 2(DUSP2)is a negative regulator of axon regeneration of the Mauthner cell(M-cell).DUSP2 is a phosphatase that mediates the dephosphorylation of *** this study,we knocked out dusp2 by CRISPR/Cas9 and found that M-cell axons of dusp2(-/-)zebrafish had a better regeneration at the early stage after birth(within 8 days after birth),while those of dusp2^(+/-)zebrafish did *** of DUSP2 in Tg(Tol 056)zebrafish by single-cell electroporation retarded the regeneration of M-cell *** blotting results showed that DUSP2 knockout slightly increased the levels of phosphorylated *** findings suggest that knocking out DUSP2 promoted the regeneration of zebrafish M-cell axons,possibly through enhancing JNK phosphorylation.

关键词： axon regeneration central nervous system CRISPR/Cas9 DUSP2 JNK Mauthner cell single-cell electroporation spinal cord injury two-photon axotomy zebrafish

Multiple Nanoparticles Coupling Strategy for Enhancing Optical Filter Performance of Spectral Splitter Used in Photovoltaic/Thermal System

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Journal of Thermal Science 2024年第1期33卷 368-382页

作者： liang Huaxu HUANG xin wang Fuqiang CHENG Ziming DONG Yan School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China School of New Energy Harbin Institute of Technology at WeihaiWeihai 264209China School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore

Selective absorptive nanofluid can pre-absorb certain sunlight wavelength that cannot be used by PV and transmits remaining sunlight to the surface of PV,which can decouple PV from the thermal receiver *** order to improve the harvesting of electricity and high-temperature thermal nanofluid,it is important to design an optimal optical filter window(transmit sunlight with wavelengths of 732-1067 nm to the surface of the photovoltaic cell and absorb the remaining sunlight).However,designing optimal optical filter is facing following challenges:(1) inherently narrow selective absorptivity property of single nanoparticle;(2) simplified numerical calculation method calculating transmittance;(3) ignoring the shape of the *** this study,the idea of using multiple nanoparticles coupling effect to design an optical filter is proposed,which can superimpose the narrow absorption bandwidth of different nanoparticles to obtain a wide absorption bandwidth of the whole *** addition,an improved transmission method considering light-matter interaction at air/vessel and liquid/vessel interfaces is adopted to compute the *** results calculated by improved transmission method are more accurate than widely used traditional Lambert-Beer law,which is verified by experimental ***,the effect of nanoparticle shape on spectral transmittance is also investigated,which shows that spiny Ag can approximately extend absorbance from 400 nm to 600 nm compared to nanosphere ***,the results show that optical filter efficiency of nanofluids with multiple nanoparticles coupling(Ag,spiny Ag,ZnO,ITO) can reached up to 35%.

关键词： solar energy PV/T nanofluid optimal optical filter radiative transfer spectral splitting

Formation and transformation of metastable LPSO building blocks clusters in Mg-Gd-Y-Zn-Zr alloys by spinodal decomposition and heterogeneous nucleation

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Journal of Magnesium and Alloys 2024年第2期12卷 673-686页

作者： xin Zhao Zhong Yang Jiachen Zhang Minxian liang Liying wang School of Materials Science and Chemical Engineering Xi’an Technological UniversityXi’an 710021China Xi’an Tianli Metal Composite Material Co.Ltd. Xi’an 710299China

To study the formation and transformation mechanism of long-period stacked ordered(LPSO)structures,a systematic atomic scale analysis was conducted for the structural evolution of long-period stacked ordered(LPSO)structures in the Mg-Gd-Y-Zn-Zr alloy annealed at 300℃~500℃.Various types of metastable LPSO building block clusters were found to exist in alloy structures at different temperatures,which precipitate during the solidification and homogenization *** stability of Zn/Y clusters is explained by the first principles of density functional *** LPSO structure is distinguished by the arrangement of its different Zn/Y enriched LPSO structural units,which comprises local fcc stacking sequences upon a tightly packed *** presence of solute atoms causes local lattice distortion,thereby enabling the rearrangement of Mg atoms in the different configurations in the local lattice,and local HCP-FCC transitions occur between Mg and Zn atoms occupying the nearest neighbor *** finding indicates that LPSO structures can generate necessary Schockley partial dislocations on specific slip surfaces,providing direct evidence of the transition from 18R to *** of the LPSO,devoid of any defects and non-coherent interfaces,was observed separately from other precipitated *** a result,the precipitation sequence of LPSO in the solidification stage was as follows:Zn/Ycluster+Mg layers→various metastable LPSO building block clusters→18R/24R LPSO;whereas the precipitation sequence of LPSO during homogenization treatment was observed to be as follows:18R LPSO→various metastable LPSO building block clusters→14H *** these,14H LPSO was found to be the most thermodynamically stable structure.

关键词： LPSO Spinodal decomposition Homogenization treatment Clusters Phase transformation

Time Evolution and Squeezing of Degenerate and Non-degenerate Coupled Parametric Down-Conversion with Driving Term

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Communications in Theoretical Physics 2009年第3期51卷 514-518页

作者： LI Jiang-Fan FANG Jia-Yuan XIAO Fu-liang LIU xin-Hai wang Cheng-Zhi School of Physics and Electronic Science Changsha University of Science and Technology Changsha 410076 China

By properly selecting the time-dependent unitary transformation for the linear combination of the number operators, we construct a time-dependent invariant and derive the corresponding auxiliary equations for the degenerate and non-degenerate coupled parametric down-conversion system with driving term. By means of this invariant and the Lewis-Riesenfeld quantum invariant theory, we obtain closed formulae of the quantum state and the evolution operator of the system. We show that the time evolution of the quantum system directly leads to production of various generalized one- and two-mode combination squeezed states, and the squeezed effect is independent of the driving term of the Hamiltonian. In some special cases, the current solution can reduce to the results of the previous works.

关键词： coupled parametric down-conversion time evolution Lewis-Riesenfeld invariant theory Schrodinger equation squeezed states

Realizing the purification and grain refinement of Mg-Gd-Y alloy by one-step flux refining

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Journal of Materials Science & Technology 2024年第6期173卷 202-217页

作者： xin Tong Guohua Wu Ming Sun Qiman wang liang Zhang Wencai Liu National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China

In the conventional melt preparation of magnesium rare-earth(Mg-RE)alloys,the repeated heating/cooling process involved in grain refinement and flux refining usually prolongs the preparation period and aggravates melt *** this work,the purification and grain refinement of Mg-9Gd-3Y(GW93)alloy was simultaneously realized by one-step refining at 740℃ by using a self-developed compound *** results show that,only after holding for 10 min,the inclusion content of the alloy is reduced by 81%to 0.29%,while the grain size is reduced by 84%to 119μm.A physical model depicting the interactions between compound flux and alloy melt was proposed based on thermodynamic calculation and microstructure *** grain refinement mechanism has been analyzed by considering the presence of Zr particle(Zr_(p))and Zr solute(Zr_(s)).In addition,the generated RECl_(3) was found to be readily absorbed by the flux,decreasing the surface tension and promoting the purification efficacy of the flux,which plays an important role in the promoted elongation of the as-cast Mg-9Gd-3Y-0.5Zr(GW93K)*** work presents a unique prospect in simplifying the melt preparation of Mg-RE alloy with a promoted quality.

关键词： Mg-Gd-Y-Zr alloy Purification Grain refinement Compound flux Settling behavior