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Holographic topological semimetals

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Science China(Physics,Mechanics & Astronomy) 2020年第5期63卷 6-30页

作者： Karl Landsteiner Yan Liu Ya-wen sun Instiuto de Fisica Teorica UAM/CSIC C/Nicolas Cabrera 13-15Campus CantoblancoCantoblanco 28049Spain Center for Gravitational Physics Department of Space ScienceBeihang UniversityBejing 100191China Key Laboratory of Space Environment Monitoring and Information Processing Ministry of Indusry and Information Technology.Beijing 100191China School of Physics&CAS Center for Excllence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100049China Kavli Institute for Theoretical Sciences University of Chinese Academy of SciencesBeijing 100049China

The holographic duality allows to construct and study models of strongly coupled quantum matter via dual gravitational *** general such models are characterized by the absence of quasiparticles, hydrodynamic behavior and Planckian dissipation times. One particular interesting class of quantum materials are ungapped topological semimetals which have many interesting properties from Hall transport to topologically protected edge states. We review the application of the holographic duality to this type of quantum matter including the construction of holographic Weyl semimetals, nodal line semimetals, quantum phase transition to trivial states(ungapped and gapped), the holographic dual of Fermi arcs and how new unexpected transport properties,such as Hall viscosities arise. The holographic models promise to lead to new insights into the properties of this type of quantum matter.

关键词： gauge/gravity duality topological semimetal Weyl semimetal anomaly

Synthesis of a novel illite@carbon nanocomposite adsorbent for removal of Cr(Ⅵ)from wastewater

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Journal of Environmental Sciences 2017年第7期29卷 62-71页

作者： Gaofeng Wang Shan Wang wen sun Zhiming sun Shuilin Zheng School of Chemical and Environmental Engineering China University of Mining and Technolooy(Beijing)Beijing 100083China

A novel illite@carbon（I@C） nanocomposite adsorbent has been synthesized via a facile hydrothermal carbonization process（HTC） using glucose as carbonaceous source and illite as the *** morphology,microstructure and surface properties of the prepared nanocomposite adsorbent were analyzed by FESEM,TGA,XRD,FT-IR and Zeta potential *** experiments were carried out on the adsorption of Cr（Ⅵ） to determine the adsorption properties of the *** adsorption of Cr（Ⅵ） onto the I@C nanocomposite was well described by the pseudo-second-order kinetic model and Langmuir *** with the illite and carbon material（SC） separately,the prepared I@C nanocomposite adsorbent exhibited enhanced adsorption performance for Cr（Ⅵ） with a maximum adsorption capacity of 149.25 mg/g,which was higher than that of most reported *** addition,the adsorption process was spontaneous and endothermic based on the adsorption thermodynamics *** adsorption of Cr（Ⅵ） by I@C was highly p H-dependent and the optimum adsorption occurred at p H *** Zeta potential analysis results indicated that the electrostatic interactions between anionic Cr（Ⅵ） and the positively charged surface of the adsorbent might be critical to the adsorption *** study demonstrated that the I@C nanocomposite should be a promising candidate for a low-cost,environmental friendly and highly efficient adsorbent for the removal of toxic Cr（Ⅵ） from wastewater.

关键词： Illite Carbon Nanocomposite Adsorption Cr(Ⅵ)

On the global smooth solutions of 3D incompressible Hall-MHD equations

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 319-327页

作者： YUE Gao-cheng sun wen-da School of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 211106China

The present paper is devoted to the well-posedness issue for the 3D incompressible Hall-MHD system obtained from kinetic models. Our analysis strongly relies on the use of the Fourier analysis. We establish the global existence of smooth solutions for a class of large initial data, this result implies the initial velocity and magnetic field can be arbitrarily large.

关键词： 3D Hall-MHD well-posedness Fourier analysis

Edge Caching in Blockchain Empowered 6G

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China Communications 2021年第1期18卷 1-17页

作者： wen sun Sheng Li Yan Zhang School of Cybersecurity Northwestern Polytechnical UniversityXi’an 710072China School of Cyber Engineering Xidian UniversityXi’an 710071China University of Oslo Oslo 0316Norway

The sixth generation(6G)of wireless cellular networks is expected to incorporate the latest developments in network infrastructure and emerging advances in *** the age of 6G,edge caching technology will evolve towards intelligence,dynamics,and ***,the security problems of edge caching,including data tampering and eavesdropping,are seldomly considered in most *** this paper,we consider the two-hop edge caching where the blockchain and physical layer security technologies are adopted to prevent data from being tampered with and *** design blockchain-based framework to guarantee the reliability of important data such as the frequency of contents and jointly optimize content caching probability and redundancy rate to maximize the secure transmission *** simulation shows that our optimization scheme can significantly improve the secure transmission probability of edge cache network,whether facing the threat of independent eavesdropping or joint eavesdropping.

关键词： blockchain 6G edge caching physical layer security

Synthesis and Crystal Structure of S-(+)-N′-Tertbutylaminocarbonyl-N-[3-methyl-2-(4-chlorophenyl)butyryl] Thiourea

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Chinese Journal of Structural Chemistry 2007年第2期26卷 153-156页

作者： sun Chuan-wen ZHANG Xiao-Dong Bio-X Life Science Research Center Shanghai Jiaotong University Shanghai 200030 China

The title compound S-（＋）-N＇-tertbutylaminocarbonyl-N-[3-methyl-2-（4-chlorophenyl）butyryl] thiourea has been synthesized and its crystal structure was determined by singlecrystal X-ray diffraction analysis. There exist intramolecular N（2）-H（2A）…O（1）, C（17）-H（17A）… O（2） and N（3）-H（3A）…S（1） hydrogen bonds as well as intermolecular N-H…O interaction between the carbonyl and amidogen groups. Crystallographic data： CITH24ClN3O2S, Mr = 369.90, monoclinic, space group C2/c with a = 22.9922（19）, b = 14.4844（12）, c = 12.4618（11） A, β = 92.608（2）°, V = 4145.8（6） ]k3, Z = 8, Dc = 1.185 g/cm^3, F（000） = 1568, g（MoKa） = 0.298 mm^-1, R = 0.0578 and wR = 0.1308.

关键词： crystal structure S-(+)-3-methyl-2-(4-chlorophenyl)butyryl thiourea antiviral activity

Relationship between chloride diffusivity and pore structure of hardened cement paste

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第5期12卷 360-367页

作者： Guo-wen sun Wei sun Yun-sheng ZHANG Zhi-yong LIU Jiangsu Key Laboratory of Construction Materials.Southeast University Nanjing 211189china

Based on effective media theory, a predictive model, relating chloride diffusivity to the capillary pores, gel pores, tortuosity factor, and pore size distribution of hardened cement, is proposed. To verify the proposed model, the diffusion coefficient of chloride ions, the degree of hydration, and peak radius of capillary pores of cement paste specimens were measured. The predicted results for chloride diffusivity were compared with published data. The results showed that the predicted chloride diffusivity of hardened cement paste was in good agreement with the experimental results. The effect of the evolution of pore structures in cement paste on chloride diffusivity could be deduced simultaneously using the proposed model.

关键词： Hardened cement paste Chloride diffusivity Porosity Tortuosity factor Constrictivity Key words: Hardened cement paste, Chloride diffusivity, Porosity, Tortuosity factor, Conslrictivity

Rhodium-Catalyzed N-Arylation Addition of Arylboronic Acids to Ketimines

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Chinese Journal of Chemistry 2024年第18期42卷 2243-2248页

作者： Xue-Wei Qian Xing-wen sun Department of Chemistry Fudan University220 Handan RoadShanghai 200433China

Herein,we report rhodium catalyzed N-arylation via addition of arylboronic acids to electron-deficientα-iminoesters which can be prepared in high efficiency by using easily accessible B-carbonyl *** reaction is highly regiospecific to achieve the N-aryl addition efficiently with up to 99%yield under mild *** corresponding product can be further efficiently converted into indoles andaseries of other important building blocks.

关键词： Rhodium catalyzed N-Arylation addition Amines Umpolung Indole C-C coupling

Insights into bishemicyanines with long emission wavelengths and high sensitivity in viscous environments

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Chinese Chemical Letters 2020年第6期31卷 1402-1405,F0002页

作者： Jianfang Cao wen sun Jiangli Fan State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024China School of Chemical and Environmental Engineering Liaoning University of TechnologyJinzhou 121001China

A systematic spectral analysis was presented for bishemicyanine dyes(Hsd and D2)and monohemicyanine dyes(Hs and DSMI).The bishemicyanine dyes displayed long emission wavelengths,large Stokes shifts,low background quantum yields in aqueous solutions and high sensitivity in viscous *** understanding of the structure-property relationships could benefit the design of improved *** studies on these dyes revealed the three conjugated forms of bishemicyanines are in equilibrium due to two positive charges and a branched bulk *** possessed obviously lower rotating energy barrier of C-C bond rotation compared to the monohemicyanine ***,the synergetic effects of the rotation about theφ4 bond,φ5 bond andφ7 bond of the bishemicyanines(Hsd and D2)lead to lower fluorescence quantum yields in a free state and larger fluorescence quantum yield enhancements in viscous environment compared to that of monohemicyanine dyes(Hs and DSMI).The results demonstrate a foundation for interpretation of the behavior of the dyes,thus providing guidelines for future of new bishemicyanine fluorophores with specific applications.

关键词： Bishemicyanine dyes Long emission wavelength Low background quantum yield Rotating energy barrier Density functional calculations

Effect of nourishing Yin and purging fire Chinese herbal mixture on delaying light-induced premature puberty in rats

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Journal of Traditional Chinese Medicine 2024年第1期44卷 95-102页

作者： sun Yanyan XUE Yuanyuan sun wen WANG Yonghong YU Jian Department of Traditional Chinese Medicine Children's Hospital of Fudan UniversityShanghai 201102China Department of Pediatrics Zibo Central HospitalZibo 255000China

OBJECTIVE:To elucidate the mechanism of the nourishing Yin and purging fire Chinese herbal mixture(NYPF)in delaying light-induced premature puberty in ***:Twenty-one days old female SpragueDawley rats were randomly assigned to normal group(N),long light exposure group(L),NYPF and normal saline group(NS).Rats in the L,NYPF and NS groups were exposed to 16 h:350 lux light/8 h:dark,while rats in the N group were exposed to 12 h:50 lux light/12 h:*** and normal saline was administered to the rats in the NYPF group or NS group,respectively,from day *** rats in every group were sacrificed at 9 *** day 28(P28),on the day when rat's vulva opened in the L group(L-VO),on the day when the first estrous interphase occurred in rats of L group(L-E1),and on the day when the second estrous interphase occurred in rats of L group(L-E2),***:On day 34,all rats in the L group,80%of rats in the NS group,40%of rats in the N group,and 20%of rats in the NYPF group showed complete opening of the *** P28,m RNA level of hypothalamic kisspeptin(Kiss-1)in the L group was significantly higher than that in the N group(P<0.05).The rats in the L and NS groups had significantly lower hypothalamic argininephenylalanine-amide(RFamide)-related peptide 3(RFRP-3)m RNA levels than those in the N group(P<0.05),whereas RFRP-3 m RNA level was significantly higher in the NYPF group than that in the L group(P<0.05).At L-VO,the ovarian index of the L and NS groups was significantly higher than that of the N group(P<0.05)and estradiol(E2)level of the NYPF group was significantly lower than that of the N and NS groups(P<0.05);hypothalamic Kiss-1 m RNA level in the L and NS groups was significantly higher than that in the N and NYPF groups(P<0.05),whereas hypothalamic RFRP-3 m RNA level in the L,NYPF,and NS groups was significantly lower than that in the N group(P<0.05).At L-E1,E2 level of the L and NS groups was significantly higher than that of the N group(P<0.01),wher

关键词： light puberty precocious kisspeptins RFRP-3 melatonin Nourishing Yin and Purging Fire