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Metal-organic frameworks with dinuclear metal centers for synergistically boosting CO2 photoreduction

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Science China Chemistry 2025年第01期 201-208页

作者： Hui-Feng Wang Wen-Jie Shi Yu-Xin Yang Bao-xia dong Tong-Bu Lu Di-Chang Zhong School of Chemistry and Chemical Engineering Yangzhou University Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and Engineering Tianjin University of Technology

Dinuclear metal synergistic catalysis （DMSC） has been proved powerful in boosting CO2reduction,while this has not been achieved in heterogeneous catalysts with long-range order *** this study,we,by introduction of metal catalytic centers into an indium-based metal-organic framework （MOF）,obtained a series of isostructural In-MOFs,including three MOFs with mononuclear metal catalytic center （M-In）,three MOFs with dinuclear homometallic catalytic centers （MM-In）,and three MOFs with dinuclear heterometallic catalytic centers (MM’-In,M/M’=Co（II）,Ni（II）,Zn（II）).It was found that all these MOFs can serve as catalysts for photochemical CO2reduction to *** with M-In,the catalytic activities of MM-In were obviously enhanced,and that of MM’-In was further significantly *** example,the CO yield of Co Zn-In reaches a record value of 12,700μmol g-1h-1,which is 4.0,8.1,9.4,and 18.6-fold higher than that of Co Co-In,Zn Zn-In,Co-In,and Zn-In,***,the catalytic activities of Co Ni-In and Ni Zn-In also show different fold increase than those of corresponding dinuclear homometallic and mononuclear metallic *** results of control experiments and theoretical calculation reveal that the higher catalytic activities of MM-In over M-In can be ascribed to the DMSC effect,and the higher catalytic activity of MM’-In over MM-In can be ascribed to the strengthened DMSC *** work reveals the relationship between DMSC effect and bimetal centers in CO2reduction,which provides new insights into the DMSC and paves a new way to design highly active catalysts for photochemical CO2reduction.

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Single foggy image restoration based on spatial correlation analysis of dark channel prior

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Journal of Systems Engineering and Electronics 2014年第4期25卷 688-696页

作者： Yan Tian dong xia Yiping Xu National Key Laboratory of Science and Technology on Multi-spectral Information Processing Huazhong University of Science and Technology

Focusing on the degradation of foggy images, a restora- tion approach from a single image based on spatial correlation of dark channel prior is proposed. Firstly, the transmission of each pixel is estimated by the spatial correlation of dark channel prior. Secondly, a degradation model is utilized to restore the foggy image. Thirdly, the final recovered image, with enhanced contrast, is obtained by performing a post-processing technique based on just-noticeable difference. Experimental results demonstrate that the information of a foggy image can be recovered perfectly by the proposed method, even in the case of the abrupt depth changing scene.

关键词： foggy image image restoration dark channel prior,spatial correlation.

Quick estimation of the D_(pb) for predicting the strength of chemical bond in situ

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Chinese Chemical Letters 2013年第10期24卷 912-916页

作者： xia Du dong-xia Zhao Zhong-Zhi Yang Chemistry and Chemical Engineering Faculty Liaoning Normal University

An approximate method has been established to calculate the depth of the potential acting on an electron in a molecule at the saddle point along a chemical bond, denoted by Dpb. It is a new indicator which can be used for predicting the strength of a chemical bond. In this work, as a practical application for demonstrating this method, we calculated the Dpb of deoxyribonucleosides and ribonucleosides along all C-H and N-H chemical bonds using the method. The results are in fair agreement with those results of previously reported experimental and theoretical observations,

关键词： Bond strength Dpb Deoxyribouncleosides Ribonucleosides

Soil Microbial and Enzymatic Activities Across a Chronosequence of Chinese Pine Plantation Development on the Loess Plateau of China

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Pedosphere 2012年第1期22卷 1-12页

作者： YUAN Bing-Cheng YUE dong-xia School of Real Estate Beijing Normal University Zhuhai CampusZhuhai 519087(China) MOE Key Laboratory of Western China's Environmental System Lanzhou UniversityLanzhou 730000(China)

Successional and seasonal effects on soil microbial and enzymatic properties were studied in Chinese pine （Pinus tabulaeformis） plantations in an age sequence of 3-, 7-, 13-, 21- and 28-year-old in northern Ziwuling region in the middle of Loess Plateau, China. The results indicated that plantation age and season affected soil microbial and enzymatic parameters significantly. Soil organic C, total N, microbial biomass C, microbial quotient, basal respiration, dehydrogenase, N-α-benzoyl-L-argininamide （BAA）-protease, urease and β-glucosidase increased quickly and tended to be highest at PF21 （21-year plantation）, thereafter they remained nearly at a constant level, whereas the metabolic quotient （qCO2） showed an initial increase and then decreased gradually. Measures of these soil properties showed significant seasonal fluctuations except for organic C and total N, which were found to be relatively stable throughout the study period, and the seasonal distributions were autumn 〉 spring 〉 summer 〉 winter for microbial biomass C, microbial quotient, dehydrogenase, and β-glucosidase; autumn 〉 summer 〉 spring 〉 winter for BAA-protease and urease; and summer 〉 autumn 〉 spring 〉 winter for basal respiration and qCO2. Significant season x age interaction was observed for biomass C, basal respiration, dehydrogenase and BAA-protease.

关键词： dehydrogenase metabolic quotient microbial biomass seasonality soil basal respiration

Propagation of polarized photons through a cavity withan anisotropic metamaterial

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Frontiers of physics 2016年第6期11卷 167-173页

作者： Yun-xia dong Jing-Jiang You School of Electrical and Electronic Engineering North China Electric Power University Beijing 102206 China

We present a theoretical study of the propagation properties of polarized photons passing through the cavity with an anisotropic metamaterial. We find that the resonant peaks of transmission appear for photons polarized in a certain direction corresponding to a negative element of the permittivity tensor. This indicates the potential for applying such cavity structures as filters for photons with certain polarizations. The resonant peak of transmission for photons having a given frequency can be achieved by adjusting the thicknesses of the air and metamaterial. If the frequency of the incident photons and the thickness of the metamaterial are fixed, the cavity structure can be used as a photon switch controlled by the thickness of the air. The effect of the absorption is considered, and the result shows that the transmission peak always appears, even for metamaterials with large absorption. Finally, the polarization manipulation of such structures is explored.

关键词： anisotropic metamaterial polarized photon cavity structure

Moments of the maximum of normed partial sums of ρ^--mixing random variables

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Applied Mathematics(A Journal of Chinese Universities) 2009年第3期24卷 355-360页

作者： LIU xiang-dong LIU Jin-xia Dept. of Statist. Jinan Univ. Guangzhou 510630 China

Let {Xn,n ≥ 1} be a sequence of identically distributed ρ^--mixing random variables and set Sn =∑i^n=1 Xi,n ≥ 1,the suffcient and necessary conditions for the existence of moments of supn≥1 ｜Sn/n^1/r｜^p（0 〈 r... 详细信息

关键词： moment of supremum of normed partial sum ρ^--mixing random variable

A decadal abruption of midwinter storm tracks over North Pacific from 1951 to 2010

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Atmospheric and Oceanic Science Letters 2016年第4期9卷 235-245页

作者： YANG dong-xia Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences

Based on 60-year （1951-2010） reanalysis data of the National Oceanic and Atmospheric Administration and extended reconstructed sea surface temperatures, a detailed investigation was conducted to explore the midwinter storm track changes over the North Pacific. The root- mean-square （rms） of subweekly （2.5-6 days） transient of 300 hPa geopotential height field was calculated to represent the storm track. A decadal abruption occurred in 1982/1983, according to the Mann-Kendall test result. The first two Empirical Orthogonal Function （EOF） spatial patterns of the North Pacific storm track during P1 （1955-1982） and P2 （1983-2010） revealed opposite results：The EOF1 during P1 and the EOF2 during P2 revealed changes of intensity of the midwinter storm track in the North Pacific, whereas the EOF2 during P1 and the EOF1 during P2 exhibited a southward/northward shift of its central axis. In addition, pronounced differences in the thermal influence of the ocean on the storm track during P1 and P2 existed. A strong and sustained ENSO signal contributed to a storm track variation through the westerly jet from1955 to 1982, as the storm track was observed to strengthen and shift equatorward during El Ni6o events. From 1983 to 2010, an apparent sea temperature frontal zone at approximately 40°N and the associated near-surface baroclinicity resulted in the organization of a prominent mid-latitude storm track throughout the depth of the troposphere.

关键词： Storm track midwinter EOF ENSO oceanic front baroclinicity

Corrosion inhibition of stainless steel by a sulfate-reducing bacteria biofilm in seawater

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International Journal of Minerals,Metallurgy and Materials 2012年第8期19卷 717-725页

作者： Fu-shao Li Mao-zhong An dong-xia Duan School of Chemistry and Chemical Engineering Qujing Normal University Qujing 655011 China State Key Laboratory for Marine Corrosion and Protection Qingdao 266071 China Chemical Engineering School Harbin Institute of Technology Harbin 150001 China

Corrosion inhibition of stainless steel due to a sulfate-reducing bacteria （SRB） biofilm in seawater was studied. By atomic force microscopy, a layer of fish-scale-like biofilm was found to form as stainless steel coupons were exposed to the culture media with SRB, and this biofilm grew more and more compact. As a result, coupons＇ surface under the biofilm turned irregular less slowly than that exposed to the sterilized culture media. Then, physicoelectric characteristics of the electrode/biofilrn/solution interface were investigated by electro- chemical impedance spectroscopy （EIS）, and the coverage of the biofilm as well as the relative irregularity of coupons＇ surface was also re- corded by EIS spectra.. Finally, anodic cyclic polarization results further demonstrated the protective property of the biofilm. Therefore, in es- timation of SRB-implicated corrosion of stainless steel, not only the detrimental SRB metabolites but also the protective SRB biofilm as well should be taken into account.

关键词： stainless steel corrosion prevention microbiology microorganisms biofilms electrochemistry

Period ratios for standing kink and sausage modes in magnetized structures with siphon flow on the Sun

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Research in Astronomy and Astrophysics 2016年第6期16卷 69-84页

作者： Hui Yu Shao-xia Chen Bo Li Li-dong xia Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong University

Standing oscillations with multiple periods have been found in a number of atmospheric struc- tures on the Sun. The ratio of the period of the fundamental to twice the one of its first overtone, P1/2192, is important in applications of solar magneto-seismology. We examine how field-aligned flows impact P1/2P2 of standing modes in solar magnetic cylinders. For coronal loops, the flow effects are significant for both fast kink and sausage modes. For kink modes, they reduce P1/2P2 by up to 17% relative to the static case even when the density contrast between the loop and its surroundings approaches infinity. For sausage modes, the reduction in P1/2P2 due to flow is typically ≤ 5.5% compared with the static case. However, the threshold aspect ratio, only above which can trapped sausage modes be supported, may increase dramatically with the flow magnitude. For photospheric tubes, the flow effect on P1/2P2 is not as strong. However, when applied to sausage modes, introducing field-aligned flows offers more possibilities in interpreting the multiple peri- ods that have recently been measured. We conclude that field-aligned flows should be taken into account to help better understand what causes the departure of P1/2P2 from unity.

关键词： magnetohydrodynamics (MHD) -- Sun: corona -- Sun: magnetic fields -- waves