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Effect of poly(ethylene glycol) molecular weight on CO_2/N_2 separation performance of poly(amide-12-b-ethylene oxide)/poly(ethylene glycol) blend membranes

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Journal of energy Chemistry 2019年第1期28卷 39-45页

作者： Shichao Feng Jizhong Ren Dan Zhao Hui Li Kaisheng Hua Xinxue Li Maicun Deng State Key laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences National laboratory for clean energy Dalian Institute of Chemical Physics Chinese Academy of Sciences

Membranes from block copolymer poly(amide-12-b-ethylene oxide)(Pebax1074) and its blends with different molecular weight poly(ethylene glycol)(PEG)(200, 400, 600, 1500, 4600 and 8000) were prepared. The thermal properties and structures of Pebax1074/PEG blend membranes were characterized by DSC and SEM, and the gas permeation properties of CO_2 and N_2 were also investigated at different temperatures. For Pebax1074/PEG blend membranes with low molecular weight PEG(MW≤ 600), higher gas permeabilities than Pebax1074 were achieved. The permeability increased with the increase of PEG molecular weight. The addition of low molecular weight PEG resulted in decrease in activation energy of permeation. For Pebax1074/PEG blend membranes with high molecular weight PEG(MW≥ 1500), due to the melt of PEO phase crystals, the gas permeation properties of blend membranes were temperaturedependent, which could be divided into crystalline region, transition region and amorphous region according to two different transition temperatures. PEG molecular weight and operation temperature determined different gas permeation properties of Pebax1074/PEG blend membranes in three regions. The activation energies of permeation in crystalline region were larger than those in amorphous region.

关键词： Poly(amide-12-b-ethylene oxide) Polyethylene glycol Blend membrane Carbon dioxide separation

Transferring and Bounding Single Photon in Waveguide Controlled by quantum Node Based on Atomic Ensemble

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Communications in Theoretical Physics 2009年第9期52卷 500-506页

作者： LU Jing DONG Hui KUANG Le-Man Key laboratory of Low-Dimensional quantum structures and quantum Control of Ministry of Education and Depart- ment of Physics Hunan Normal University Changsha 410081 China Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China

We study the scattering process of photons confined in a one-dimensional optical waveguide by a laser controlled atomic ensemble. The investigation leads to an alternative setup of quantum node controlling the coherent transfer of single photon in such one dimensional continuum. To exactly solve the effective scattering equations by using the discrete coordinate approach, we simulate the linear waveguide as a coupled resonator array at the high energy limit. We generally calculate the transmission eoet^cients and its vanishing at resonance reflects the good controllability of our scheme. We also show that there exist two bound states to describe the localize photons around the cavity.

关键词： one-dimensional waveguide single photon bound states

Exotic vector charmonium and its leptonic decay width

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Chinese Physics C 2016年第8期40卷 11-19页

作者：陈莹邱伟峰宫明桂龙成刘朝峰 Institute of High energy Physics Chinese Academy of Sciences Beijing 100049 China Theoretical Center for Science Facilities Chinese Academy of Sciences Beijing 100049 China Department of Physics and Synergetic Innovation Center for quantum Effects and Applications Hunan Normal University Changsha 410081 China Key laboratory of Low-Dimensional quantum structures and quantum Control of Ministry of Education Changsha 410081 China

We propose a novel type of interpolating field operator, which manifests the hybrid-like configuration that the charm quark-antiquark pair recoils against gluonie degrees of freedom. A heavy vector charmonium-like state with a mass of 4.33（2） GeV is disentangled from the conventional charmonium states in the quenched approximation. This state has affinity for the hybrid-like operators but couples less to the relevant quark bilinear operator. We also try to extract its leptonic decay constant and give a tentative upper limit that it is less than one tenth of that of J/ψ, which corresponds to a leptonic decay width about dozens of eV. The connection of this state with X（4260） is also discussed.

关键词： X(4260) hybrid charmonium leptonic decay constant

Cascaded electron transition in CuWO4/CdS/CDs heterostructure accelerating charge separation towards enhanced photocatalytic activity

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Chinese Chemical Letters 2020年第6期31卷 1516-1519页

作者： Yibo Chen Jing-Feng Li Pei-Yu Liao Ying-Shan Zeng Zhu Wang Zhao-Qing Liu School of Chemistry and Chemical Engineering Guangzhou Key Laboratory for Clean Energy and MaterialsGuangzhou UniversityGuangzhou 510006China

CuWO4,as an n-type oxide semiconductor with a bandgap of 2.2 eV,has stimulated enormous interest as a potential broad-spectrum-active photocatalyst for environmental pollution ***,rapid charge recombination greatly hinders its practical ***,we present a cascaded electron transition pathway in a ternary heterostructure consisting of CdS quantum dots,carbon dots(CDs)and CuWO4 hollow spheres,which proves to greatly facilitate the photogenerated electron-hole separation,and eventually boosts the degradation efficiency of phenol and congo red by 100%and 46%compared to bare *** enhanced performance of the CuWO4/CdS/CDs heterostructure mainly originates from the unidirectional electron migration from CdS to CuWO4 and then to the organics through *** work elucidates the electron transfer kinetics in multi-phase system and provides a new design paradigm for optimizing the properties of CuWO4 based photocatalysts.

关键词： Cascaded electron transition CuWO4 Hollow spheres Carbon dots Photocatalysis

Solids Acceleration Length in a Cold Dense Transport Bed

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Journal of Thermal Science 2012年第6期21卷 533-538页

作者： Yunhan Xiao Shengdian Wang Shaojun Yang Kai Zhao Xin Zeng Xiang XU Key laboratory of Advanced energy and Power Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100190 China Center for clean energy and Power Chinese Academy of Sciences Beijing 100190 China

The solids acceleration length was investigated in a cold dense transport bed （0.10 m-IDx17 m-height） with three kinds of Silica sand. The solids circulation rate （Gs） was up to 954 kg/（m2s）. The effects of operating conditions, particle properties, and riser structures on the solids acceleration length were investigated under high Gs conditions, with the effect of riser height non-negligible. The solids acceleration length increased with the increase of the riser height. Based on the experimental data, an empirical correlation was proposed to predict the solids acceleration length. Predictions of the correlation were in good agreement with the experimental data in this work and those from the literature over a wide range of Gs （18~954 kg/（m2s））.

关键词： dense transport bed gas-solid two-phase flow solids acceleration length

Application of machine learning in perovskite materials and devices:A review

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Journal of energy Chemistry 2024年第7期94卷 254-272页

作者： Ming Chen Zhenhua Yin Zhicheng Shan Xiaokai Zheng Lei Liu Zhonghua Dai Jun Zhang Shengzhong(Frank)Liu Zhuo Xu School of Electric Power Civil Engineering and ArchitectureCollege of Physics and Electronics EngineeringState Key Laboratory of Quantum Optics and Quantum Optics DevicesShanxiUniversityTaiyuan030006ShanxiChina Key laboratory of Applied Surface and Colloid Chemistry National Ministry of EducationShanxi Engineering Lab for Advanced Energy TechnologySchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an 710119ShaanxiChina State Key laboratory of Catalysis Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Metal-halide hybrid perovskite materials are excellent candidates for solar cells and photoelectric *** recent years,machine learning(ML)techniques have developed rapidly in many fields and provided ideas for material discovery and *** can be applied to discover new materials quickly and effectively,with significant savings in resources and time compared with traditional experiments and density functional theory(DFT)*** this review,we present the application of ML in per-ovskites and briefly review the recent works in the field of ML-assisted perovskite ***,the advantages of perovskites in solar cells and the merits of ML applied to perovskites are ***,the workflow of ML in perovskite design and some basic ML algorithms are ***,the applications of ML in predicting various properties of perovskite materials and devices are ***,we propose some prospects for the future development of this *** rapid devel-opment of ML technology will largely promote the process of materials science,and ML will become an increasingly popular method for predicting the target properties of materials and devices.

关键词： Machine learning Perovskite Materials design Bandgap engineering Stability Crystal structure

A possible explanation of the threshold enhancement in the process e^+e^-→∧■

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Chinese Physics C 2019年第11期43卷 49-57页

作者： Li-Ye Xiao Xin-Zhen Weng Xian-Hui Zhong Shi-Lin Zhu School of Physics and State Key laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Center of High energy Physics Peking UniversityBeijing 100871China Department of Physics Hunan Normal Universityand Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of EducationChangsha 410081China Synergetic Innovation Center for quantum Effects and Applications(SICQEA) Hunan Normal UniversityChangsha 410081China Collaborative Innovation Center of quantum Matter Beijing 100871China

Inspired by the recent measurement of the process e+e-→∧■,we calculate the mass spectrum of the 0 meson with the GI *** the excited vector strangeonium states ?（3 S,4 S,5 S,6 S） and ?（2 D,3 D,4 D,5 D）,we investigate the electronic decay width with the Van Royen-Weisskopf formula,and the partial widths of the ∧■,■,and■ decay modes with the extended quark-pair creation *** find that the electronic decay width of the D-wave vector strangeonium is about 3～8 times larger than of the S-wave vector *** 2232 Me V,the partial decay width of the ∧■ mode can be up to several MeV for ?（33 S1）,while the partial ∧■ decay width of ?（23 D1） is O(10-3) *** the threshold enhancement reported by the BESIII collaboration arises from the strangeonium meson,this state is very likely the ?（33 S1） *** also note that the ∧■ and∑+■partial decay widths of the states ?（33 D1） and ?（43 S1） are several MeV,which is sufficient to be observed in future experiments.

关键词： spectrum GI mode ΛΛ^-decay

Design of Supercapacitor Electrodes Using Molecular Dynamics Simulations

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Nano-Micro Letters 2018年第2期10卷 162-184页

作者： Zheng Bo Changwen Li Huachao Yang Kostya Ostrikov Jianhua Yan Kefa Cen State Key laboratory of clean energy Utilization College of Energy Engineering Zhejiang University School of Chemistry Physics and Mechanical EngineeringQueensland University of Technology Joint CSIRO-QUT Sustainable Processes and Devices laboratory

Electric double-layer capacitors(EDLCs) are advanced electrochemical devices for energy storage and have attracted strong interest due to their outstanding properties. Rational optimization of electrode–electrolyte interactions is of vital importance to enhance device performance for practical applications. Molecular dynamics(MD) simulations could provide theoretical guidelines for the optimal design of electrodes and the improvement of capacitive performances, e.g., energy density and power density. Here we discuss recent MD simulation studies on energy storage performance of electrode materials containing porous to nanostructures. The energy storage properties are related to the electrode structures, including electrode geometry and electrode modifications. Altering electrode geometry, i.e., pore size and surface topography,can influence EDL capacitance. We critically examine different types of electrode modifications, such as altering the arrangement of carbon atoms, doping heteroatoms and defects, which can change the quantum capacitance. The enhancement of power density can be achieved by the intensified ion dynamics and shortened ion *** control of the electrode morphology helps improve the ion dynamics by decreasing the ion diffusion pathway. Tuning the surface properties(e.g., the affinity between the electrode and the ions) can affect the ionpacking phenomena. Our critical analysis helps enhance the energy and power densities of EDLCs by modulating the corresponding electrode structures and surface properties.

关键词： Electric double-layer capacitors Molecular dynamics Porous structure Nanostructure

Even-odd-dependent optical transitions of zigzag monolayer black phosphorus nanoribbons

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Science China(Physics,Mechanics & Astronomy) 2021年第1期64卷 91-101页

作者： Pu Liu XianZhe Zhu XiaoYing Zhou GuangHui Zhou Kai Chang Department of Physics Key Laboratory for Low-Dimensional Structures and Quantum Manipulation(Ministry of Education)Synergetic Innovation Center for Quantum Effects and Applications of HunanHunan Normal UniversityChangsha410081China SKLSM Institute of SemiconductorsChinese Academy of SciencesBeijing100083China

We analytically study the electronic structure and optical properties of zigzag-edged phosphorene nanoribbons(ZPNRs) using the tight-binding Hamiltonian and Kubo formula. By directly solving the discrete Schrodinger equation, we obtain the energy spectra and wavefunctions for N-ZPNR(where N is the number of transverse zigzag atomic chains) and classify the eigenstates according to the lattice symmetry. Then, we obtain the optical transition selection rule of ZPNRs on the basis of symmetry analysis and analytical expressions of optical transition matrix elements. Under incident light that is linearly polarized along the ribbon, we determine that the optical transition selection rule for N-ZPNR with even-or odd-N is qualitatively different. Specifically, for even-N ZPNRs, the inter-(intra-) band selection rule is ?n =odd(even) because the parity of the wavefunction corresponding to the n-th subband in the conduction(valence) band is(-1)~n[(-1)~((n+1))] owing to the presence of C(2x) symmetry. However, the optical transitions between any subbands are possible owing to the absence of C(2x) symmetry. Our results provide a further understanding on the electronic states and optical properties of ZPNRs, which are useful for explaining the optical experiment data on ZPNR samples.

关键词： zigzag-edged phosphorene nanoribbons band structure light absorption selection rules