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Carbonaceous aerogel and CoNiAl-LDH@CA nanocomposites derived from biomass for high performance pseudo-supercapacitor

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Science Bulletin 2017年第12期62卷 841-845页

作者： Sidi zhang Jian Liu Peipei Huang hao Wang Changyan Cao Weiguo Song Beijing National Laboratory for Molecular Sciences Key Laboratory of Molecular Nanostructure and NanotechnologyCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China The Academy of Military Economics Student Brigade Wuhan 430035China

Conversion of waste biomass to valuable carbonaceous material is a sustainable and environmental benign method for energy and reduction of greenhouse gas emission. Herein, a two-step hydrothermal method was developed to fabricate high performance electrode material from pomelo peels. In the first step, the pomelo peels were transformed to carbonaceous aerogel （CA）, which constructed of three- dimensional, sponge-like brown monolith with hierarchical pores, low-density （0.032 g]cm3） and excel- lent mechanical flexibility. Then, the cobalt nickel aluminum layered double hydroxide （CoNiAI-LDH） was in situ loaded on the surface of CA to form exquisite core-shell structure （CoNiAI-LDH@CA） through the second hydrothermal step. When used as an electrode material for supercapacitor, CoNiA1-LDHOCA exhibited high specific capacitances of 1,134f/g at 1A/g and 902fig at 10A/g, respectively. furthermore, they displayed an excellent cycling stability without an obvious capacitance decrease after 4,000 cycles.

关键词： BiomassCarbonaceous aerogelLayered double hydroxideSupercapacitor

Statefinder diagnostic and constraints on the Palatini f(R) gravity theories

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Research in Astronomy and Astrophysics 2018年第3期18卷 11-26页

作者： Shu-Lei Cao Song Li hao-Ran Yu Tong-Jie zhang Department of Astronomy Beijing Normal University Department of Physics Capital Normal University Tsung-Dao Lee Institute Shanghai Jiao Tong University School of Information Management School of Physics and Electric InformationShandong Provincial Key Laboratory of BiophysicsDezhou University

We focus on a series of f(R) gravity theories in Palatini formalism to investigate the probabilities of producing late-time acceleration for the flat friedmann-Robertson-Walker(fRW) *** apply a statefinder diagnostic to these cosmological models for chosen series of parameters to see if they can be distinguished from one another. The diagnostic involves the statefinder pair{r,s},where r is derived from the scale factor a and its higher derivatives with respect to the cosmic time t,and s is expressed by r and the deceleration parameter q. In conclusion,we find that although two types of f(R) theories:(i) f(R) = R + αR~m-βR-nand(ii) f(R) = R + α lnR-β can lead to late-time acceleration,their evolutionary trajectories in the r-s and r-q planes reveal different evolutionary properties,which certainly justify the merits of the statefinder diagnostic. Additionally,we utilize the observational Hubble parameter data(OHD) to constrain these models of f(R) gravity. As a result,except for m = n = 1/2 in case(i),α = 0 in case(i) and case(ii) allow the ΛCDM model to exist in the 1σ confidence region. After applying the statefinder diagnostic to the best-fit models,we find that all the best-fit models are capable of going through the deceleration/acceleration transition stage with a late-time acceleration epoch,and all these models turn to the de Sitter point({r,s}={1,0}) in the future. Also,the evolutionary differences between these models are distinct,especially in the r-s plane,which makes the statefinder diagnostic more reliable in discriminating cosmological models.

关键词： dark energy cosmology:miscellaneous methods:data analysis

Uniquely identifying topological order based on boundary-bulk duality and anyon condensation

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National Science Review 2023年第3期10卷 117-126页

作者： Yong-Ju Hai Ze zhang hao Zheng Liang Kong Jiansheng Wu Dapeng Yu Shenzhen Institute for Quantum Science and Engineering Southern University of Science and Technology Department of Physics Southern University of Science and Technology International Quantum Academy Guangdong Provincial Key Laboratory of Quantum Science and Engineering

Topological order is a new quantum phase that is beyond Landau’ s symmetry-bre aking *** defining features include robust degenerate ground states,long-range entanglement and *** was known that R and f matrices,which characterize the fusion-braiding properties of anyons,can be used to uniquely identify topological *** this article,we explore an essential question:how can the R and f matrices be experimentally measured?We show that the braidings,*** R matrices,can be completely determined by the half braidings of boundary excitations due to the boundary-bulk duality and the anyon *** f matrices can also be measured by comparing the quantum states involving the fusion of three anyons in two different *** we provide a model-independent experimental protocol to uniquely identify topological *** using quantum simulations based on a toric code model with boundaries encoded in three-and four-qubit systems and state-of-the-art technology,we obtain the first experimental measurement of R and f matrices by means of an NMR quantum computer at room temperature.

关键词： topological order R matrix f matrix bulk-boundary duality anyon condensation

Meridional movement of northern and southern equatorial ionization anomaly crests in the East-Asian sector during 2002-2003SSW

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Science China Earth Sciences 2017年第4期60卷 776-785页

作者： MO XiaoHua zhang DongHe Larisa GONCHARENKO zhang ShunRong hao YongQiang XIAO Zuo PEI JiaZheng Akimasa YOSHIKAWA CHAU HaDuyen College of Science Guangxi University for Nationalities Department of Geophysics Peking University Haystack Observatory Massachusetts Institute of Technology School of Automation Wuhan University of Technology Earth and Planetary Sciences International Center for Space WeatherKyushu University Hanoi Institute of Geophysics Vietnamese Academy of Science and Technology

The present paper investigates the asymmetrical variability of the location of the north and the south equatorial ionization anomaly(EIA) crests in the East-Asian sector,along with their association with simultaneous observations of equatorial electrojet(EEJ) strength,geomagnetic activity index,and solar flux index during the 2002-2003 sudden stratospheric wanning(SSW) *** of these observations indicates the existence of a large-scale quasi 16-day periodic meridional movement in both EIA crests,and also reveals a strong correlation between the quasi 16-day oscillation in geomagnetic latitudes of the EIA crest and EEJ *** latitude of the northern/southern EIA crest and the EEJ strength indicate that obvious synchronous periodic oscillations were in-phase in the northern and southern hemisphere when the SSW *** addition,it is also found that both the EIA crest location and amplitude of the periodic movement of the EIA locations exhibit hemispheric *** amplitude of the periodic movement of the EIA location in the southern hemisphere is larger than that of the northern hemisphere,and the southern EIA crest is further off from the equator than the north *** these asymmetries requires a combination of mechanisms that involve at least trans-equator meridional winds and the position of a sub-solar point;however,potential disturbances in neutral winds associated with the SSW may additionally complicate the equatorial ionospheric dynamics.

关键词： Active experiments Ionosphere f1-region Electric fields

Observational study of daytime ionospheric irregularities associated with typhoon

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Science China(Technological Sciences) 2012年第5期55卷 1302-1304页

作者： XIAO SalGuan SHI JianKui zhang DongHe hao YongQiang HUANG WeiQuan State Key Laboratory of Space Weather Center for Space Science and Applied ResearchChinese Academy of SciencesBeijing 100190China Department of Geophysics Peking UniversityBeijing 100871China

Spread-f is a manifestation of ionospheric irregularities and generally takes place at nighttime. However, it can also be ob- served seldom at daytime, It is recognized that acoustic gravity waves （AGWs） play an important role in triggering plasma instability which results in spread-f in the ionosphere. The typhoon is a main source of the AGWs. In this paper, two cases of ionospheric daytime spread-f in the period of typhoon were analyzed. One case was on July 29, 1988 and the other was on August 01, 1989. The results showed the following： 1） There were some wave-like disturbances appearing in the Hf Doppler records firstly, consequently the Doppler echo traces became scattered, which indicated that the ionospheric spread-f was triggered; 2） the blurred echo traces in the both two cases appeared in the morning （08：30-11：30 Beijing time） and lasted for more than two hours; 3） with the blurred echoes gradually weakening, the traveling ionospheric disturbances （TIDs） still ex- isted and became clearer; 4） the frequency shifts in the two of the radio wave in the ionosphere moved downwards. spread-f during the typhoon period in Asian region. cases were both positive, implying the effective reflecting surface These results provide good observational evidence for daytime

关键词： ionospheric irregularity spread-f daytime typhoon

Crystal Structure of Dimethylamine 3,5-Dinitrobenzoic Acid Organic Adduct

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Chinese Journal of Structural Chemistry 2006年第8期25卷 1011-1013页

作者： ZHU Jun zhang Yun CHEN hao CHE Yun-Xia ZHENG Ji-Min Department of Chemistry Nankai University lianjin 300071 China

The title adduct （C9H11N3O6, Mr= 257.21） was synthesized and it crystallizes in orthorhombic, space group P212121 with a = 5.8835（19）, b =9.517（3）, c = 20.399（6） A, V= 1142.2（6） ,A^3 Z = 4, Dc= 1.496 g/cm^3, f（000） = 536,μ（MoKα） = 0.128 mm^-1, the final R = 0.0396 and wR = 0.0800 for 1047 observed reflections with I 〉 2σ（I）. The compound is a 1：1 adduct of dimethylamine and 3,5-dinitrobenzoic acid which are linked by hydrogen bonds to form a two-dimensional network. The dimethylamine is protonated at the nitrogen atom with the proton from the carboxyl of 3,5- dinitrobenzoic acid.

关键词： dimethylamine 3,5-dinitrobenzoic acid hydrogen bond crystal structure nonlinear optical

On the robustness of EEG tensor completion methods

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Science China(Technological Sciences) 2021年第9期64卷 1828-1842页

作者： DUAN feng JIA hao zhang ZhiWen fENG fan TAN Ying DAI YangYang CICHOCKI Andrzej YANG ZhengLu CAIAfA Cesar f. SUN Zhe SOLE-CASALS Jordi College of Artificial Intelligence Nankai UniversityTianjin 300350China Skolkowo Institute of Science and Technology Moscow 121205Russia College of Computer Science Hangzhou Dianzi UniversityHangzhou 310018China Department of Informatics Nicolaus Copernicus UniversityTorun 87-100Poland Systems Research Institute Polish Academy of SciencesWarsaw 01-447Poland College of Computer Science Nankai UniversityTianjin 300350China Instituto Argentino de Radioastronom´ıa IAR-CCT La Plata CONICET/CIC-PBA/UNLPVilla Elisa 1894Argentina Computational Engineering Applications Unit Head Office for Information Systems and CybersecurityRIKENWako-Shi 351-0106Japan Department of Psychiatry University of CambridgeCambridge CB28AHUK Data and Signal Processing Research Group University of Vic-Central University of CataloniaCatalonia 08500Spain

During the acquisition of electroencephalographic(EEG) signals, data may be missing or corrupted by noise and artifacts. To reconstruct the incomplete data, EEG signals are firstly converted into a three-order tensor(multi-dimensional data) of shape time × channel × trial. Then, the missing data can be efficiently recovered by applying a tensor completion method(TCM).However, there is not a unique way to organize channels and trials in a tensor, and different numbers of channels are available depending on the EEG setting used, which may affect the quality of the tensor completion results. The main goal of this paper is to evaluate the robustness of EEG completion methods with several designed parameters such as the ordering of channels and trials, the number of channels, and the amount of missing data. In this work, the results of completing missing data by several TCMs were compared. To emulate different scenarios of missing data, three different patterns of missing data were ***, the amount of missing data on completion effects was analyzed, including the time lengths of missing data and the number of channels or trials affected by missing data. Secondly, the numerical stability of the completion methods was analyzed by shuffling the indices along channels or trials in the EEG data tensor. finally, the way that the number of electrodes of EEG tensors influences completion effects was assessed by changing the number of channels. Among all the applied TCMs, the simultaneous tensor decomposition and completion(STDC) method achieves the best performance in providing stable results when the amount of missing data or the electrode number of EEG tensors is changed. In other words, STDC proves to be an excellent choice of TCM, since permutations of trials or channels have almost no influence on the complete results. The STDC method can efficiently complete the missing EEG signals. The designed simulations can be regarded as a procedure to validate whether or

关键词： electroencephalogram corrupted data missing data tensor completion tensor decomposition

Caterpillar-like 3D graphene nanoscrolls@CNTs hybrids decorated with Co-doped MoSe_(2)nanosheets for electrocatalytic hydrogen evolution

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Journal of Materials Science & Technology 2023年第5期136卷 43-53页

作者： hao Luo Hongfei Gao Xudong zhang fan Yang Chen Liu Kewei Xu Dagang Guo State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Center for High Performance Computing Network Information CenterXi’an Jiaotong UniversityXi’an 710049China

Hydrogen is a clean and flexible energy carrier that has the promising to satisfy urgent demands of the energy crisis and environmental *** hydrogen evolution reaction(HER),a critical half-reaction in water splitting,is one of the greenest and most common methods to obtain high-purity *** preeminent activity and stability electrocatalysts for hydrogen precipitation reac-tion(HER)to reduce energy consumption is of great essential.3D carbon-based materials have attracted widespread concern as the potential scaffolds of highly active and durable electrocatalysts for *** boost the HER activity and prolong the lifespan of electrocatalysts,multifarious 3D carbon architectures make an appearance to be engineered for accelerating electronic/mass transfer and maximizing the expo-sure of active ***,we designed and fabricated high-performance electrocatalysts based on a spe-cial caterpillar-like 3D graphene nanoscrolls@CNTs(GNS@CNTs)scaffold decorated with Co-doped MoSe_(2)nanosheets for *** the caterpillar-like hierarchical structure,CNTs were seamlessly co-bonded and dilated the interlayer and outer spacing of GNS through CVD growth technology,and nickel nanoparticles were covered by the CNTs *** advantage of the plentiful hierarchical pore,larger specific surface area,and higher chemical stability of the caterpillar-like structure,the catalysts exhibited enhanced elec-trocatalytic properties than some existing data *** functional theory calculations showed that the encapsulated nickel nanoparticle could tune the electronic structure of the outer anchored Co-doped MoSe_(2)and optimize itsG of H∗adsorption by electron traversing effect and doping *** indicate that caterpillar-like GNS@CNT is an ideal scaffold f or anchoring actives substance and is suit-able for high-efficient *** study provides new insights for designing hierarchical carbon composite nanostructures for catalysts,sensors,

关键词： Electron traversing effect 3D graphene Graphene nanoscrolls CNT MoSe_(2),Hydrogen evolution reaction

Superior Pseudocapacitive Storage of a Novel Ni3Si2/ NiOOH/Graphene Nanostructure for an All‑Solid‑State Supercapacitor

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Nano-Micro Letters 2021年第1期13卷 15-28页

作者： Jing Ning Maoyang Xia Dong Wang Xin feng Hong Zhou Jincheng zhang Yue hao The State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology Xidian UniversityXi’an 710071People’s Republic of China Shaanxi Joint Key Laboratory of Graphene Xidian UniversityXi’an 710071People’s Republic of China

Recent developments in the synthesis of graphene-based structures focus on continuous improvement of porous nanostructures,doping of thin films,and mechanisms for the construction of threedimensional ***,we synthesize creeper-like Ni3Si2/NiOOH/graphene nanostructures via low-pressure all-solid meltingreconstruction chemical vapor *** a carbon-rich atmosphere,high-energy atoms bombard the Ni and Si surface,and reduce the free energy in the thermodynamic equilibrium of solid Ni–Si particles,considerably catalyzing the growth of Ni–Si *** controlling the carbon source content,a Ni3Si2 single crystal with high crystallinity and good homogeneity is stably *** measurements indicate that the nanostructures exhibit an ultrahigh specific capacity of 835.3 C g^−1(1193.28 f g^−1)at 1 A g^−1;when integrated as an all-solidstate supercapacitor,it provides a remarkable energy density as high as 25.9 Wh kg^−1 at 750 W kg^−1,which can be attributed to the freestanding Ni3Si2/graphene skeleton providing a large specific area and NiOOH inhibits insulation on the electrode surface in an alkaline solution,thereby accelerating the electron exchange *** growth of the high-performance composite nanostructure is simple and controllable,enabling the large-scale production and application of microenergy storage devices.

关键词： Pseudocapacitive storage Creeper-like Ni3Si2 NiOOH Graphene All-solid-state supercapacitors