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The discovery of a quantum Griffiths singularity in superconducting films

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National Science Review 2016年第4期3卷 395-396页

作者： nan-Lin Wang International center for Quantum Materials School of PhysicsPeking University

More than 40 years ago,Robert B Griffiths proposed that phase transitions can be dramatically changed by a disorder effect and,in particular,that it is possible for the dynamical critical exponent to diverge[1].Since that time,this theory has been applied to quantum phase transitions(QPTs)and has been developed into the concept of the quantum Griffiths ***,the primary

关键词： very SMT The discovery of a quantum Griffiths singularity in superconducting films

Effects of building aspect ratio,diurnal heating scenario,and wind speed on reactive pollutant dispersion in urban street canyons

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Journal of Environmental Sciences 2012年第12期24卷 2091-2103页

作者： Nelson y.O.Tong Dennis y.c.Leung Department of Mechanical Engineering The University of Hong Kong

A photochemistry coupled computational fluid dynamics （cFD） based numerical model has been developed to model the reactive pollutant dispersion within urban street canyons, particularly integrating the interrelationship among diurnal heating scenario （solar radiation affections in nighttime, daytime, and sun-rise/set）, wind speed, building aspect ratio （building-height-to-street-width）, and dispersion of reactive gases, specifically nitric oxide （NO）, nitrogen dioxide （NO2） and ozone （O3） such that a higher standard of air quality in metropolitan cities can be achieved. Validation has been done with both experimental and numerical results on flow and temperature fields in a street canyon with bottom heating, which justifies the accuracy of the current model. The model was applied to idealized street canyons of different aspect ratios from 0.5 to 8 with two different ambient wind speeds under different diurnal heating scenarios to estimate the influences of different aforementioned parameters on the chemical evolution of NO, NO2 and 03. Detailed analyses of vertical profiles of pollutant concentrations showed that different diurnal heating scenarios could substantially affect the reactive gases exchange between the street canyon and air aloft, followed by respective dispersion and reaction. Higher building aspect ratio and stronger ambient wind speed were revealed to be, in general, responsible for enhanced entrainment of 03 concentrations into the street canyons along windward walls under all diurnal heating scenarios. comparatively, particular attention can be paid on the windward wall heating and nighttime uniform surface heating scenarios.

关键词： photochemistry reactive pollutant dispersion building aspect ratio diurnal heating scenario wind speed urban streetcanyon

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语言文字视角下“五谷”的文化内涵

语文教学之友 2025年第1期44卷 6-8页

作者：张亚南廊坊师范学院文学院

“五谷”代表中国古代农业文明的丰富成果,也蕴含深厚的人文精神。通过对文献中“五谷”含义的系统梳理,认为解释为黍、稷、麦、菽、稻最合理。语文教学中加深学生对“五谷”文化内涵的认识,有助于学生更好地理解古诗文,增进对中国传统... 详细信息

“五谷”代表中国古代农业文明的丰富成果,也蕴含深厚的人文精神。通过对文献中“五谷”含义的系统梳理,认为解释为黍、稷、麦、菽、稻最合理。语文教学中加深学生对“五谷”文化内涵的认识,有助于学生更好地理解古诗文,增进对中国传统文化的认同,培养民族自豪感和文化自信。

关键词：五谷黍稷麦稻菽

Boosting charge extraction and efficiency of inverted perovskite solar cells through coordinating group modification at the buffer layer/cathode interface

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nano Research 2025年第1期18卷 415-423页

作者： Zhiqing Liang Ziqiu Ren Ziyu Wang nan yan Ling Li Bo Zhang yanlin Song college of chemistry Zhengzhou UniversityZhengzhou 450052China Key Laboratory of Applied Surface and colloid chemistry Ministry of Education Shaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy Technology School of Materials Science and EngineeringShaanxi Normal UniversityXi’an 710119China Key Laboratory of Green Printing Institute of ChemistryChinese Academy of Sciences(ICCAS)Beijing Engineering Research Center of Nanomaterials for Green Printing TechnologyNational Laboratory for Molecular Sciences(BNLMS)Beijing 100190China

In inverted perovskite solar cells (PScs),effective modification of the interface between the metalcathode and electron transport layer (ETL) is crucial forachieving high performance and stability. Herein, sulfonatedbathocuproine, commonly known as disodium bathocuproinedisulfonate (BcDS), was employed as a cathode buffer layerto address the interfacial issues at the [6,6]-phenyl-c61-butyricacid methyl ester (PcBM)/Ag interface. BcDS possesses theability to form coordinate bonds with Ag electrodes. Theutilization of the BcDS buffer layer enhanced the chargeextraction capability at the cathode interface whilesimultaneously achieving interfacial defect passivation,improving interfacial contact and increasing the built-in electricfield. consequently, a power conversion efficiency (PcE) of25.06% was achieved. Furthermore, owing to the excellent filmforminguniformity of BcDS on PcBM, the stability of thedevice was also improved. After storage in dry air for morethan 2000 h, the device maintained 96% of its initial efficiency. This work underscores the remarkable potential of tailoringcoordination groups to enhance charge extraction efficiency at the ETL-cathode interface, unveiling a promising newfrontier in buffer layer development and performance optimization strategies for PScs.

关键词： perovskite solar cells buffer layer bathocuproine disulfonate coordination group modification electron transport layer(ETL)-cathode interface

Effect of phase-separated patterns on the formation of core-shell structure

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Journal of Materials Science & Technology 2020年第3期38卷 64-72页

作者： yinli Peng nan Wang MOE Key Laboratory of Materials Physics and chemistry under Extraordinary conditions School of Natural and Applied SciencesNorthwestern Polytechnical UniversityXi’an710072China

Revealing the mechanisms of self-organized core-shell(c-S)structure in immiscible systems has drawn considerable attentions,however,the further and fundamental understanding from the point of view of phase-separated pattern remains extremely *** this work,by realizing two phase-separated patterns in transparent immiscible system,namely nucleation-growth and spinodal decomposition,their effects on radius of minority-phase droplet(MPD)were examined,and subsequently the effect on c-S structure was further *** was found that compared with MPDs produced via nucleation-growth,the MPDs via spinodal decomposition are much larger and easier to form a c-S *** is mainly because the larger MPDs can migrate faster and are earlier to reach the sample’s *** addition,two pathways of core formation were observed during the formation of c-S structure:one evolves from a ringlike structure in the phase separation of spinodal decomposition;the other derives from the collision of numerous MPD at sample’s *** a difference is ascribed to the combination of different growth kinetics and the volume fractions of *** findings might provide an in-depth insight into the c-S structure formation in immiscible systems.

关键词： Phase separation Immiscible system Nucleation Spinodal decomposition core-shell structure

MEcHANIcAL PROPERTIES OF Ti_3Sic_2 AT HIGH TEMPERATURE

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 465-470页

作者： y.W.Bao y.c.Zhou Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 ChinaShenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

creep and stress relaxation behavior, the elastic modulus and fracture toughness of machinable Ti3Sic2 at various temperatures from 20 to 1250℃ were investigated by means of three-point bending tests. The experiments were performed respectively at: (i) fixed stress and changed temperatures, and (ii) fixed temperature and changed stresses. A creep resistance parameter that represents the probability of creep deformation in a given condition was defined as a function of both applied stress and the threshold stress, varying in a range from 0 to 1. Elastic modulus at high temperatures was measured through comparing relative slopes of loading curves in cyclic loading curve. The fracture toughness measured by SENB method showed a stable value in the range of 25-1000℃, but over 1000℃, it declined abruptly from -6.7MPa·m1/2 to -2.0MPa·m1/2 at 1200℃.

关键词： high-temperature Ti3Sic2 creep stress relaxation fracture toughness

Mechanical formula for the plastic limit pressure of stent during expansion

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Acta Mechanica Sinica 2009年第6期25卷 795-801页

作者： Jie yang nan Huang School of Mechanics and Engineering Southwest Jiaotong University 610031 Chengdu China School of Material Science and Engineering Southwest Jiaotong University 610031 Chengdu China

The mechanics of cardiovascular stents during the process of expansion are very important for stent function and safety. In general, finite element method （FEM） or experi- ments are major methods used to ascertain mechanical prop- erties of the stent. In this paper, we develop a theoretical model of the tubular stent, derive formulas for the axial forces and moments on the stent end, and propose formu- las for the plastic limit pressure vs. the stent＇s radius during expansion. Examples covering different geometrical param- eters and material parameters are provided, and the plastic limit pressures calculated by FEM and the present method are compared, proving that the present formulas are acceptable and meaningful for the design and innovation of the stent.

关键词： Stent. Expansion . Inter forcePlastic limit pressure . FEM

Microstructure,phase composition and wear resistance of low valence electron concentration Al_(x)cocrFeNiSi high-entropy alloys prepared by vacuum arc melting

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Journal of Iron and Steel Research International 2021年第2期28卷 181-189页

作者： Bing-qian Jin nan-nan Zhang yue Zhang De-yuan Li Department of Material Science and Engineering Shenyang University of TechnologyShenyang 110870LiaoningChina Provincial Key Laboratory of Advanced Welding Technology and Automation Shenyang 110870LiaoningChina

The low valence electron concentration(VEc)Al_(x)cocrFeNiSi(x=0.5,1.0,1.5 and 2.0)high-entropy alloys(HEAs)were designed by the fundamental properties of the constituent elements and prepared by vacuum arc melting *** effects of Al addition on the crystal structure and microstructure were *** microhardness and wear property were also *** results showed that the microstructure transformed from dendritic crystal to equiaxed *** was found that Fcc phase gradually decreased with the increasing Al content and disappeared until in a composition of 1.0 in Al_(x)cocrFeNiSi *** Fcc phase was found with continuously adding Al,while the phase fraction of Bcc increased from 85.0% to 91.8%,and VEc decreased from 7.00 to *** microhardness was increased gradually from 598 up to 909 HV with addition of Al from 0.5 to *** was the same of the compressive strength results,which improved from 1200 to 1920 *** wear coefficient and mass loss were in line with mechanical properties evolution,which was attributed to the microstructure transformation into equiaxed crystal and the increase in Bcc phase.

关键词： High-entropy alloy Valence electron concentration Microstructure Phase assemblage Wear resistance

A FRAMEWORK FOR REAL-VALUED cIPHER SySTEMS

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Journal of Systems Science & complexity 2007年第4期20卷 486-491页

作者： Zhaozhi ZHANG nan JIANG Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China college of computer Science and Technology Beijing University of Technology Beijing 100022 China

Most cipher systems designed thus far are binary-valued or integer-valued cipher systems. Their security relies on the assumption that one-way functions exist. Though the existence of one-way functions has not been proved yet, most cryptographic researchers believe that one-way functions exist. In addition, many candidates for one-way functions have been proposed. Therefore, the key step for developing real-valued cipher systems is to define real one-way functions and to propose candidates for them. In this paper, based on computational complexity theory over the real field, we give two definitions of real one-way functions; one is for digital one-way functions and the other is for general one-way functions. candidates for these two classes of one-way functions are also proposed. Moreover, we present two examples to demonstrate that the candidates for both digital one-way functions and general one-way functions can be applied to construct secure real-valued cipher systems.

关键词： computational complexity theory digital one-way function general one-way function real-valued cipher system.