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Spin coating of TPB film on acrylic substrate and measurement of its wavelength shifting efficiency

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Nuclear Science and Techniques 2020年第3期31卷 57-65页

作者： Hang Yang zi-feng Xu Jian Tang Yi Zhang School of Physics Sun Yat-sen UniversityGuangzhou 510275China School of Chemistry Sun Yat-sen UniversityGuangzhou 510275China

Scintillation light from a liquid noble gas during a neutrino or dark matter experiment lies typically within the vacuum ultraviolet region and might be strongly absorbed by surrounding materials such as light guides or *** butadiene(TPB)is a fluorescent material,acts as a wavelength shifter,and can turn UV light into visible light at a peak wavelength of approximately 425 nm,enabling the light signals to be easily detected during physics *** with a traditional TPB coating method using vapor deposition,we propose an alternative technique applying a spin-coating procedure to facilitate the development of neutrino and dark matter *** article introduces a method to fabricate a TPB film on an acrylic substrate by using a spincoating method,reports the measurements of the sample film thickness and roughness,demonstrates the reemission spectrum,and quantifies the wavelength shifting efficiency.

关键词： Wavelength shifter Tetraphenyl butadiene Spin-coating method

Eigenstates of Laser-Assisted Scattering in a Noninertial Frame

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Communications in Theoretical Physics 2005年第6X期44卷 1002-1006页

作者： feng zi-Min LI Shu-Min Department of Modern Physics University of Science and Technology of China P.O. Box 4 Hefei 230026 China

In a rotating noninertial frame, we investigate the eigenstates of the time-dependent problem for electronnucleus scattering assisted by a circularly polarized laser field. Numerical results of probability distribution, quantum potential, and current density are discussed. An approximate expression of scattering cross section for low laser frequency is given.

关键词： noninertial frame laser field scattering eigenstate

Diffusion and catalyst efficiency in hierarchical zeolite catalysts

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National Science Review 2020年第11期7卷 1726-1742页

作者： Peng Peng Xiong-Hou Gao zi-feng Yan Svetlana Mintova State Key Laboratory of Heavy Oil Processing China University of Petroleum Laboratory of Catalysis and Spectrochemistry (LCS) Normandy University National Graduate School of Engineering of Caen (ENSICAEN)University of Caen (UNICAEN) French National Center for Scientific Research (CNRS) Petrochemical Research Institute China National Petroleum Company

The preparation of hierarchical zeolites with reduced diffusion limitation and enhanced catalyst efficiency has become a vital focus in the field of zeolites and porous materials chemistry within the past decades. This review will focus on the diffusion and catalyst efficiency of hierarchical zeolites and industrial catalysts. The benefits of diffusion and catalyst efficiency at two levels of hierarchies (zeolitic component level and industrial catalyst level) from a chemical reaction engineering point of view will be analysed. At zeolitic component level, three types of mesopores based on the strategies applied toward enhancing the catalyst effectiveness factor are presented:(i)‘functional mesopores’(raising effective diffusivity);(ii)‘auxiliary mesopores’(decreasing diffusion length); and (iii)‘integrated mesopores’(a combination thereof). At industrial catalyst level, location and interconnectivity among the constitutive components are *** hierarchical pore interconnectivity in multi-component zeolite based industrial catalysts is exemplified by fluid catalytic cracking and bi-functional hydroisomerization catalysts. The rational design of industrial zeolite catalysts at both hierarchical zeolitic component and catalyst body levels can be fully comprehended using the advanced in situ and/or operando spectroscopic, microscopic and diffraction techniques.

关键词： diffusion effectiveness factor pore connectivity hierarchical zeolite industrial catalyst advanced characterization

A TVD-WAF-based hybrid finite volume and finite difference scheme for nonlinearly dispersive wave equations

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Water Science and Engineering 2015年第3期8卷 239-247页

作者： Jing Yin Jia-wen Sun zi-feng Jiao National Marine Environment Monitoring Center State Oceanic Administration State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology

A total variation diminishing-weighted average flux （TVD-WAF）-based hybrid numerical scheme for the enhanced version of nonlinearly dispersive Boussinesq-type equations was developed. The one-dimensional governing equations were rewritten in the conservative form and then discretized on a uniform grid. The finite volume method was used to discretize the flux term while the remaining terms were approximated with the finite difference method. The second-order TVD-WAF method was employed in conjunction with the Harten-Lax-van Leer （HLL） Riemann solver to calculate the numerical flux, and the variables at the cell interface for the local Riemann problem were reconstructed via the fourth- order monotone upstream-centered scheme for conservation laws （MUSCL）. The time marching scheme based on the third-order TVD Runge- Kutta method was used to obtain numerical solutions. The model was validated through a series of numerical tests, in which wave breaking and a moving shoreline were treated. The good agreement between the computed results, documented analytical solutions, and experimental data demonstrates the correct discretization of the governing equations and high accuracy of the proposed scheme, and also conforms the advantages of the proposed shock-capturing scheme for the enhanced version of the Boussinesq model, including the convenience in the treatment of wave breaking and moving shorelines and without the need for a numerical filter.

关键词： Hybrid scheme Finite volume method (FVM) Finite difference method (FDM) Total variation diminishing-weighted average flux (TVD-WAF) Boussinesq-type equations Nonlinear shallow water equations (NSWEs)

Abstracts of Main Essays

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哲学研究 2011年第11期 128-128,F0003页

作者： feng zi-yi 不详

On Deepening the Research on the Law of the Social Horizontal Development feng zi-yi The further development of globalization makes it urgent to deepen the research on the law of social hori- zontal development. Historical development of human society has experienced periods of isolation, multi-cen- ter, and globalization, while the truly horizontal development began from modernity. This kind of development is driven mainly by the logic of capital. The transforming process of capital, from dominating the whole process of economic development toward all aspects of social life, and from dominating nations toward the whole world, is also the logical process of capital pursuing itself and the process of social horizontal and wholly development as well. Horizontal and vertical developments of the society are interacting always. Researching on the law of social horizontal development is important for us to adapt to the historical trend consciously, to grasp the logic of capital rationally and to choose the right road of development.

关键词：英文摘要内容介绍编辑工作期刊

Preparation and Acid Catalytic Activity of TiO2 Grafted Silica MCM-41 with Sulfate Treatment

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Chinese Journal of Chemical Physics 2008年第1期21卷 21-26页

作者： Dai-shi Guo zi-feng Ma Chun-sheng Yin Qi-zhong Jiang Department of Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China School of Environmental Science and Engineering Shanghai Jiao Tong University Shanghai 200240China

TiO2 grafted silica MCM-41 catalyst with and without sulfate treatment were prepared. The structural and acid properties of these materials were investigated by XRD, N2 adsorption-desorption, element analysis, thermal analysis, Raman and FTIR measurements. Their acid-catalytic activities were evaluated using the cyclization reaction of pseudoionone. It was found that the obtained materials possess well-ordered mesostructure, and the grafted TiO2 components were in highly dispersed amorphous form. T/MCM41 without sulfation contained only Lewis acid sites, while Brφnsted and Lewis acidities were remarkably improved for the sulfated materials ST/MCM41 and d-ST/MCM41. T/MCM-41 was not active for the cyclization reaction of pseudoionone, but ST/MCM-41 and d-ST/MCM-41 possessed favorable catalytic activities. The catalytic performance of ST/MCM-41 was comparable with that of the commercial solid acid catalyst of Amberlyst-15, and better than that of d-ST/MCM-41, although the latter underwent a second TiO2 grafting process and accordingly had higher Ti and S content. The specific surface structure of Si-O-Ti-O-S=O in ST/MCM-41 and the bilateral induction effect of Si and S=O on Si-O-Ti bonds were speculated to account for its higher acid catalytic activity.

关键词： TiO2 grafting Sulfate treatment Silica MCM-41 Acid catalytic activity Cyclization of pseudoionone

Crystal Structure of Hydrochlorate of 1,1'-Bis[(4-pyridylamino)carbonyl]ferrocene

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Chinese Journal of Structural Chemistry 2005年第8期24卷 901-904页

作者： LI Gang LI zi-feng HOU Hong-Wei ZHU Yu Department of Chemistry Zhengzhou University ChinaHenan 450052

The hydrochlorate of 1,1＇-bis[（4-pyridylamino）carbonyl]ferrocene （C23H23O3N4ClFe,Mr = 494.75） was structurally characterized by means of X-ray single-crystal diffraction. It crystallizes in triclinic, space group P/ with a = 9.5299（19）, b = 12.792（3）, c = 9.2644（19） A°, a =91.56（3）,β = 101.97（3）,γ= 74.71（3）°, V = 1065.2（4） ,A°^3, Z = 2, Dc = 1.542 g/cm^3, F（000） = 512,μ（MoKa） = 0.868 mm ^-1, T = 291（2） K, the final R = 0.0596 and wR = 0.1531 for 2842 observed reflections with 1 〉 2σ（I）. Interestingly, two 1,1 ＇- bis[（4-pyridylamino）carbonyl]ferrocenes （4-BPFA） join shoulder-to-shoulder through intermolecular hydrogen bonds N-H……N, forming an unexpected macrocycle with dimensions of 3.385 ,A°× 15.778 A°.

关键词： synthesis crystal structure ferrocenyl compound

Baeyer-Villiger oxidation of ketones with hydrogen peroxide catalyzed by Sn-aniline complex

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Chinese Chemical Letters 2007年第1期18卷 4-6页

作者： Qing Hua Zhang Shou feng Wang zi Qiang Lei Key Laboratory of Polymer Materials of Gansu Province College of Chemistry and Chemical Engineering Northwest Normal University Lanzhou 730070 China

Sn-aniline complex was prepared by a simple procedure. Cyclic and acyclic ketones were oxidized into lactones or esters with very high selectivity and yield with 30% hydrogen peroxide in the presence of Sn-aniline com... 详细信息

关键词： Baeyer-Villiger oxidation Sn-aniline complex Ketone oxidation Hydrogen peroxide

Evolution of Er^(3+) Distribution in the Oxyfluoride Glass Ceramics with Heating

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Chinese Journal of Structural Chemistry 2007年第3期26卷 303-308页

作者： MA En CHEN Da-Qin HU Zhong-Jian LIU feng HUANG zi-Xiang BAO feng WANG Yuan-Sheng State Key Laboratory of Structural Chemistry Fujian Institute of Research on theStructure of Matter Chinese Academy of Sciences Fuzhou Fujian 350002 China

The distribution characteristics of Er^3＋ ions doped in the oxyfluoride glass ceramics containing LaF3 nanocrystals heat-treated at 650 ℃ for different durations were investigated. The results of the integral absorption cross-section analysis demonstrated that the partition fraction of Er^3＋ in LaF3 nanocrystals increases with prolonging of heating time, The anomalous phenomena of Er^3＋ emissions in the up-and the down-conversion fluorescence spectra are well explained based on the calculated results.

关键词： oxyfluoride glass ceramics rare earth nanocrystal up-conversion integral absorption cross-section