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多模态PET/MRI影像组学鉴定帕金森病和多系统萎缩

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国际医学放射学杂志 2024年第2期 251-251页

作者： J.J.Sun c.cong X.P.Li w.c.zhou R.X.Xia H.Liu 侯唯姝

摘要目的基于多模态PET/MRI影像组学和临床特征建立鉴别帕金森病（PD）与多系统萎缩（MSA）的机器学习模型。方法纳入119例病人（PD 81例，MSA 38例）行脑PET/

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DIELEcTRIc PROPERTIES OF NANO Si/c/N cOMPOSITE POwDER AND NANO Sic POwDER AT HIGH FREQUENcIES AND MIcROSTRUcTURE cHARAcTERIZATION

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 1136-1141页

作者： D.L.Zhao, H.S.Zhao and w.c.zhou State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072,china

The dielectric properties of nano Si/c/N composite powder and nano Sic powder at high frequencies have been studied. The nano Si/c/N composite powder and nano Sic powder were synthesized from hexamethyldisilazane ((Me 3Si) 2NH) (Me:cH 3) and SiH 4 c 2H 2 respectively by a laser induced gas phase reaction. The complex permittivities of the nano Si/c/N composite powder and nano Sic powder were measured between 8 2GHz and 12 4GHz. The real and imaginary parts of the complex permittivities of nano Si/c/N composite powder are much higher than those of nano Sic powder. The Sic microcrystalline in the nano Si/c/N composite powder dissolved a great deal of nitrogen. The local structure around Si atoms changed by introducing N into Sic. carbon atoms around Si were substituted by N atoms. So charged defects and quasi free electrons moved in response to the electric field, diffusion or polarization current resulted from the field propagation. The high ε″and loss factor tgδ(ε″/ε′) of Si/c/N composite powder were due to the dielectric relaxation.

关键词： nano Si/c/N composite powder nano Sic powder dielectric properties microstructure

THE EFFEcT OF MELTING TEMPERATURE ON THE PROPERTIES OF PbBr _2-Pbcl_2-P_2O_5 GLASSES

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 1153-1158页

作者： H.S.Zhao,w.c.zhou, D.L.Zhao and D.M.Zhu State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072,china

A series of PbBr 2 Pbcl 2 P 2O 5 glasses have been prepared and characterized to research the effect of melting temperature on the properties of glasses. The glass forming regions have been explored and the stability of the glasses against crystallization studied. The density, characteristic temperatures, chemical analysis compositions, and infrared absorption spectra of the glasses were measured. Results show that the PbBr 2 Pbcl 2 P 2O 5 ternary system melted at 530～540℃ has a broader glass forming region which extended to the side of PbBr2 than that melted at 450～470℃. The glass transition temperature is more than 200℃ and the density is more than 5 5 g·cm 3 . Both the chemical analysis composition and the infrared absorption spectra of some glasses melted at 530～540℃ show that the decomposition of NH 4H 2PO 4 is more complete than that of glasses melted at 450～470℃.

关键词： phosphate glasses melting temperature property

STUDY ON c-FIBER-REINFORcED cELSIAN-MATRIX cOMPOSITES

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 1094-1098页

作者： X.w.Yin, L.F.cheng,L.T.Zhang, w.c.zhou and Y.D.Xu State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi′an 710072, china

Strong, tough, and almost fully dense c fiber reinforced celsian matrix composites have been fabricated by impregnation of the fiber tows with the matrix slurry, winding on a drum, drying, stacking the prepreg tapes in the desired orientation, and hot pressing. The monoclinic celsian phase in the matrix was produced in situ, during hot pressing, from amphosous BAS. The unidirectional composites having ≈20 vol% of fibers exhibited graceful failure with extensive fiber pullout in three point bend tests at room temperature. Values of ultimate flexural strength and fracture toughness were 379MPa and 8 3MPa·m 1/2 , respectively.

关键词： barium aluminosilicate celsian composite sol gel carbon fiber

Efficient guiding and focusing of intense laser pulse using periodic thin slits

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Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu T.w.Huang K.Jiang c.N.wu H.Peng P.c.hen R.Li H.B.Zhuo c.T.zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material Technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

Reversed charge transfer induced by nickel in Fe-Ni/Mo_(2)c@nitrogen-doped carbon nanobox for promoted reversible oxygen electrocatalysis

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Journal of Energy chemistry 2024年第1期88卷 202-212,I0005页

作者： Zhicheng Nie Lei Zhang Qiliang Zhu Zhifan Ke Yingtang zhou Thomas wågberg Guangzhi Hu School of Materials Science and Engineering Anhui University of Science and TechnologyHuainan 232001AnhuiChina Institute for Ecological Research and Pollution control of Plateau Lakes School of Ecology and Environmental ScienceYunnan UniversityKunming 650504YunnanChina National Engineering Research center for Marine Aquaculture Marine Science and Technology CollegeZhejiang Ocean UniversityZhoushan 316004ZhejiangChina Department of Physics UmeåUniversityUmeåS-90187Sweden

The interaction between metal and support is critical in oxygen catalysis as it governs the charge transfer between these two entities,influences the electronic structures of the supported metal,affects the adsorption energies of reaction intermediates,and ultimately impacts the catalytic *** this study,we discovered a unique charge transfer reversal phenomenon in a metal/carbon nanohybrid ***,electrons were transferred from the metal-based species to N-doped carbon,while the carbon support reciprocally donated electrons to the metal domain upon the introduction of *** led to the exceptional electrocatalytic performances of the resulting Ni-Fe/Mo_(2)c@nitrogen-doped carbon catalyst,with a half-wave potential of 0.91 V towards oxygen reduction reaction(ORR)and a low overpotential of 290 m V at 10 mA cm^(-2)towards oxygen evolution reaction(OER)under alkaline ***,the Fe-Ni/Mo_(2)c@carbon heterojunction catalyst demonstrated high specific capacity(794 mA h g_(Zn)~(-1))and excellent cycling stability(200 h)in a Zn-air *** calculations revealed that Mo_(2)c effectively inhibited charge transfer from Fe to the support,while secondary doping of Ni induced a charge transfer reversal,resulting in electron accumulation in the Fe-Ni alloy *** local electronic structure modulation significantly reduced energy barriers in the oxygen catalysis process,enhancing the catalytic efficiency of both ORR and ***,our findings underscore the potential of manipulating charge transfer reversal between the metal and support as a promising strategy for developing highly-active and durable bi-functional oxygen electrodes.

关键词： Metal-support interaction charge transfer reversal Oxygen reduction reaction Oxygen evolution reaction Zinc-air battery

The preface: Interplay of topological and magnetic orders in the Mn-Bi-Te family

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National Science Review 2024年第2期11卷 6-7页

作者： Fu-chun Zhang Hai-zhou Lu X.c.Xie Kavli Institute for Theoretical Sciences University of Chinese Academy of Sciences Department of Physics Southern University of Science and Technology (SUSTech) International center for Quantum Materials School of Physics Peking University

The discovery and synthesis of MnBi2Te4in 2013 initially garnered little attention [1]. Yet, the revelation of its topological properties in 2019 [2–6] sparked a surge of research into the MnBiTe family. These extensive studies are primarily driven by two objectives:the realization of a high-temperature quantum anomalous Hall effect （QAHE） and the exploration of exotic phases born from the interplay of topological and magnetic orders,

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Spatial distributions of soil nutrients affected by land use,topography and their interactions,in the Loess Plateau of china

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International Soil and water conservation Research 2024年第1期12卷 227-239页

作者： wenxin zhou changjia Li wenwu Zhao Lindsay c.Stringer Bojie Fu State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijingChina Institute of Land Surface System and Sustainable Development Faculty of Geographical ScienceBeijing Normal UniversityBeijingChina Department of Environment and Geography University of YorkYorkUK York Environmental Sustainability Institute University of YorkYorkUK

Soil nutrient availability and their spatial distributions are strongly related to land use and landscape *** study aims to address the knowledge gap regarding the interaction between these factors and the underlying *** selected five land uses(grassland with Artemisia gmelinii,woodland with Robinia pseudoacacia,shrubland with caragana korshinskii and Hippophae rhamnoides,and apple orchard with Malus pumila)and nine slope positions across hillslopes in the Loess Plateau,china,to investigate their combined effects on the contents and stocks of soil organic carbon(SOc),total nitrogen(TN)and total phosphorus(TP).Parametric and non-parametric statistical tests were conducted to determine the significant differences in the means or the medians of the soil nutrient *** showed that the SOc and TN contents of shrubland with caragana korshinskii were statistically significantly greater than those of the grassland(pc and TN contents generally decreased from the upper slope to the middle slope,and to the foot slope for the grassland,woodland and shrublands,and on the contrary,an increasing trend from the upper slope,to the middle slope,and to the foot slope was identified for the apple *** study highlights that land use,slope position and their interaction have significant effects on the spatial distributions of soil *** provides essential empirical evidence for the identification of the optimal vegetation type and slope positions in land management and vegetation restoration activities.

关键词： Soil organic carbon Total nitrogen Total phosphorus Slope position Vegetation restoration

Progress on the antiferromagnetic topological insulator MnBi2Te4

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National Science Review 2024年第2期11卷 33-49页

作者： Shuai Li Tianyu Liu chang Liu Yayu wang Hai-zhou Lu X.c.Xie Department of Physics Harbin Institute of Technology Shenzhen Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology(SUSTech) Quantum Science center of Guangdong-Hong Kong-Macao Greater Bay Area(Guangdong) Shenzhen Key Laboratory of Quantum Science and Engineering International Quantum Academy Beijing Academy of Quantum Information Sciences Beijing Key Laboratory of Optoelectronic Functional Materials&Micro-Nano Devices Department of Physics Renmin University of China State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua University Frontier Science center for Quantum Information Hefei National Laboratory International center for Quantum Materials School of Physics Peking University Institute for Nanoelectronic Devices and Quantum computing Fudan University

Topological materials, which feature robust surface and/or edge states, have now been a research focus in condensed maTher physics. They represent a new class of materials exhibiting nontrivial topological phases,and provide a platform for exploring exotic transport phenomena, such as the quantum anomalous Hall effect and the quantum spin Hall effect. Recently, magnetic topological materials have attracted considerable interests due to the possibility to study the interplay between topological and magnetic *** particular, the quantum anomalous Hall and axion insulator phases can be realized in topological insulators with magnetic order. MnBi2Te4, as the first intrinsic antiferromagnetic topological insulator discovered, allows the examination of existing theoretical predictions; it has been extensively studied, and many new discoveries have been made. Here we review the progress made on MnBi2Te4from both experimental and theoretical aspects. The bulk crystal and magnetic structures are surveyed first, followed by a review of theoretical calculations and experimental probes on the band structure and surface states, and a discussion of various exotic phases that can be realized in MnBi2Te4. The properties of MnBi2Te4thin films and the corresponding transport studies are then reviewed, with an emphasis on the edge state transport. Possible future research directions in this field are also discussed.

关键词： MnBi2Te4 magnetic topological insulator antiferromagnetic quantum anomalous Hall effect axion insulator