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Log-behavior of Two Sequences Related to the Elliptic Integrals

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Acta Mathematicae Applicatae Sinica 2020年第3期36卷 590-602页

作者： Brian Yi SUN James jing-yu zhao Department of Mathematics and System Science Xinjiang UniversityUrumqi 830046China School of Mathematics Tianjin UniversityTianjin 300350China

Two interesting sequences arose in the study of the series expansions of the complete elliptic integrals,which are called the Catalan-Larcombe-French sequence{Pn}n≥0 and the Fennessey-Larcombe-French sequence{Vn}n≥0 *** this paper,we first establish some criteria for determining log-behavior of a sequence based on its three-term *** we prove the log-convexity of{Vn^2-V(n-1)V(n+1)}n≥2 and{n!Vn}n≥1,the ratio log-concavity of{Pn}n≥0 and the sequence{An}n≥0 of Apéry numbers,and the ratio log-convexity of{Vn}n≥1.

关键词： the Catalan-Larcombe-French sequence the Fennessey-Larcombe-French sequence Apéry numbers log-concave log-convex three-term recurrence

Adsorption and Diffusion of Hydrogen Atom on Low-index Ag Planes

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Chinese Journal of Structural Chemistry 2005年第10期24卷 1217-1223页

作者： ZHANG jing DIAO zhao-yu WANG Ze-Xin Department of Chemistry Shandong Normal University Jinan 250014 China

The 5-parameter Morse potential （5-MP） of the interaction between H atom and Ag surfaces has been constructed. The adsorption and diffusion of H on Ag low-index surfaces are investigated with 5-MP in detail. The characteristics of critical points are obtained. The theoretical results show that H atom can only adsorb at the three-fold site on Ag（111 ）; the quasi-3-fold site and long-bridge site are stable adsorption sites on Ag（110） surface for the H atom, and at low coverage hydrogen predominantly occupies the quasi-3-fold site. This work predicts that the four-fold hollow site is the most stable adsorption state for H atom on Ag（100）. The results of this work are approved by the experimental and theoretical results.

关键词： H-Ag system 5-MP adsorption vibration low-index surfaces

Adsorption and Vibration of Cl Atoms on Ni Low-index Surfaces

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Chemical Research in Chinese Universities 2006年第4期22卷 488-492页

作者： ZHANG jing DIAO zhao-yu WANG Ze-xin Department of Chemistry Shandong Normal University Jinan 250014 P. R. China

The 5-parameter Morse potential（5-MP） of the interactions between Cl atoms and Ni surfaces was constructed. The adsorption and diffusion of Cl atoms on Ni low index-surfaces were investigated with 5-MP in detail. All the critical characteristics of the system, such as adsorption site, adsorption geometry, binding energy, eigenvalues for vibration, etc. were obtained. The calculated results show that chlorine atoms are likely to be adsorbed on the high symmetry- sites. Cl atoms locate on the four-fold hollow sites of the intact Ni（100） surface, while they tend to occupy threefold sites on the Ni（ 111 ） surface. The four-fold hollow sites are the most stable adsorption sites on the Ni （110） surface for Cl, although the three-fold sites and the long-bridge sites are stable adsorption sites on the Ni（110） surface for the atoms of the first and second periods. For the Cl-Ni surface adsorption system, the surface binding energy of a Cl atom is relevant to the coarse degree of the cluster surface, and the binding energies have an order of Ni （ 111 ）〈 Ni（100）〈Ni（100）.

关键词： Cl-Ni system 5-MP Surface adsorption Surface vibration

Filling the gaps in icosahedral superatomic metal clusters

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National Science Review 2024年第7期11卷 168-176页

作者： Wei-Miao He Jia-Hua Hu yu-Jia Cui jing Li yu-Bing Si Shuai-Bo Wang yu-jing zhao Zhan Zhou Lu-Fang Ma Shuang-Quan Zang College of Chemistry Zhengzhou University School of Science Xuchang University College of Chemistry and Chemical Engineering Henan Key Laboratory of Function-Oriented Porous MaterialsLuoyang Normal University

Chemically modified superatoms have emerged as promising candidates in the new periodic table, in which Au13and its doped M_nAu13-nhave been widely studied. However, their important counterpart, Ag13artificial element, has not yet been synthesized. In this work, we report the synthesis of Ag13nanoclusters using strong chelating ability and rigid ligands, that fills the gaps in the icosahedral superatomic metal clusters. After further doping Ag13template with different degrees of Au atoms, we gained insight into the evolution of their optical properties. Theoretical calculations show that the kernel metal doping can modulate the transition of the excited-state electronic structure, and the electron transfer process changes from local excitation（LE） to charge transfer（CT） to LE. This study not only enriches the families of artificial superatoms, but also contributes to the understanding of the electronic states of superatomic clusters.

关键词： icosahedral superatomic metal clusters analog clusters photoluminescence alloying near-infrared quantum yield

Zircon U-Pb geochronologic,geochemical and Sr-Nd-Pb isotope characteristics of the Beidaban granites in the North Qilian Orogenic Belt:Petrogenesis and tectonic implications

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Acta Geochimica 2024年第6期43卷 1087-1104页

作者： Tao Yang Zhi-yuan Sun Ming-liang Wang Xiao-qiang Zhu jing-yu zhao The First Institute of Geology and Mineral Exploration Gansu Provincial Bureau of Geology and Mineral ExplorationTianshui 741020China School of Resources and Civil Engineering Suzhou UniversitySuzhou 234000China School of Geography and Tourism Anhui Normal UniversityWuhu 241000China

The tectonic evolution and crustal accretion process of the North Qilian Orogenic Belt(NQOB)are still under debate because of a lack of integrated constraints,especially the identifi cation of the tectonic transition from arc to initial *** we present results from zircon U-Pb geochronology,whole-rock geochemistry,and Sr-Nd-Pb isotope geochemistry of the Beidaban granites to provide crucial information for geodynamic evolution of *** U-Pb dating yields an age of 468±10 Ma for the Beidaban granites and most of the Beidaban samples contain amphibole,are potassium-rich,and have A/CNK values ranging from 0.7 to 0.9,illustrating that the Middle Ordovician Beidaban granites are K-rich,metaluminous,calc-alkaline *** geochemical characteristics indicate that the Beidaban granites are transitional I/S-type granitoids that formed in an arc *** isotopic compositions of initial(87 Sr/86 Sr)i values ranging from 0.70545 to 0.71082(0.70842 on average)andεNd(t)values ranging from−10.9 to−6.7(−8.8 on average)with two-stage Nd model ages(T DM2)of 1.74-2.08 Ga suggest that the Beidaban granites originated from Paleoproterozoic crustal *** addition,the initial Pb isotopic compositions(^(206)Pb/^(204)Pb=19.14-20.26;^(207)Pb/^(204)Pb=15.71-15.77;^(208)Pb/^(204)Pb=37.70-38.26)and geochemical features,such as high Th/Ta(17.43-30.12)and Rb/Nb(6.01-15.49)values,suggest that the Beidaban granite magma source involved recycled crustal components with igneous *** on these results in combination with previously published geochronological and geochemical data from other early Paleozoic igneous rocks,we suggest that the timing of the tectonic transition from arc to the initial collision to the fi nal closure of the North Qilian Ocean can be constrained to the Middle-Late Ordovician(ca.468–450 Ma).

关键词： Granitoids Zircon U-Pb dating Sr-Nd-Pb-isotopes Petrogenesis North Qilian Orogenic Belt

Inhibitory effect of oxymatrine on serum hepatitis B virus DNA in HBV transgenic mice

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World Journal of Gastroenterology 2004年第8期10卷 1176-1179页

作者： Lun-GenLu Min-DeZeng Yi-MinMao jing-yuanFang yu-LinSong zhao-HuiShen Ai-PingCao ShanghaiInstituteofDigestiveDisease RenjiHospitalShanghaiSecondMedicalUniversityShanghai200001China

AIM:To study the inhibitory effect of oxymatrine on serum hepatitis B virus (HBV) DNA in HBV transgenic mice. METHODS:HBV transgenic mice model was established by microinjection,and identified by HBV DNA integration and *** mice with replicating HBV were divided into 3 groups,and injected with normal saline (group A,n=9),50 mglkg (group B,n=8) and 100 mg/kg (group C,n=9) oxymatrine intraperitoneally once a day for 30d,*** of serum HBV DNA in HBV transgenic mice was performed by competitive polymerase chain reaction (PCR) in combination with DNA hybridization quantitative detection technique before and after treatment. RESULTS:Compared with pre-treatment,the serum HBV DNA in group A (F=1.04,P=0.9612) and group B (F=1.13, P=0.8739) had no changes after ***,in group C serum HBV DNA was significantly decreased (F=13.97, P=0.0012).The serum HBV DNA after treatment was lower in group C than in groups B and A (F=8.65,P=0.0068; F=12.35,P=0.0018;respectively).The serum HBV DNA after treatment was lower in group B than in group A,but there was no statistical significance (F=1.43,P=0.652). CONCLUSION:Oxymatrine has inhibitory effects on serum HBV DNA in HBV transgenic mice.

关键词：氧化苦参碱血清学检查药理作用乙型病毒性肝炎转基因技术动物模型

STRUCTURE ASSIGNMENT FOR EPIMERIC THYMIDINE-3'-YL BENZOIN PHOSPHATES

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Chinese Chemical Letters 1995年第7期6卷 577-580页

作者： Xin CHEN, yu Ping FENG, Nan jing ZHANG, yu Fen zhao (Bio-organic Phosphorus Chemistry Laboratory, Department of Chemistry Tsinghua University, Beijing 100084) Tsing Hua Univ Dept Chem Bioorgan Phosphorus Chem Lab Beijing 100084 Peoples R China

Reaction of Oxyphosphorane (1) with thvmidine (2) followed .by hydrolysis under mild conditions afforded TMP, TpT and thymidine-3'-yl benzoin phosphates(3). The structures of 3 were determined by 31P, 1H. 13C,NMR and mass spectral data. and 31P-1H COSY experiments. The possible formation mechanism of 3 was also discussed.

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Geomagnetic field absenee reduces adult body weight of a migratory insect by disrupt!ng feeding behavior and appetite regulation

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Insect Science 2021年第1期28卷 251-260页

作者： Gui-Jun Wan Shou-Lin Jiang Ming Zhang jing-yu zhao Ying-Chao Zhang Wei-Dong Pan Gregory A.Sword Fa-Jun Chen Department of Entomology Nanjing Agricultural UniversityNanjingChina Beijing Key Laboratory of Bioelectromagetics Institute of Electrical EngineeringChinese Academy of SciencesBeijingChina Department of Entomology Texas A&M UniversityCollege StationTXU.S.A.

The geomagnetic field(GMF)is well documented for its essential role as a cue used in animal orientation or *** evidence indicates that the absence of GMF(mimicked by the near-zero magnetic field,NZMF)can trigger stress-like responses such as reduced body weight,as we have previously shown in the brown planthopper,Nilaparvata *** this study,we found that consistent with the significantly decreased body weight of newly emerged female(—14.67%)and male(—13.17%)adult ***,the duration of the phloem ingestion feeding waveform was significantly reduced by 32.02%in 5th instar nymphs reared under the NZMF versus ***,5th instar nymphs that exhibited reduced feeding had significantly higher glucose levels(+16.98%and+20.05%;24 h and 48 h after molting),which are associated with food aversion,and expression patterns of their appetite-related neuropeptide genes(neuropeptide F,dow regulated overall;short neuropeptide F,dowregulated overall;adipokinetic hormone up-regulated overall;and adipokinetic hormone receptor,down-regulated overall)were also altered under the absence of GMF in a manner consistent with diminishing ***,the expressions of the potential magnetosensor croptochromes(Crys)were found significantly altered under the absence of GMF,indicating the likely upstream signaling of the Cry-mediated magnetoreception *** findings support the hypothesis that strong changes in GMF intensity can reduce adult body weight through affecting insect feeding behavior and underlying regulatory processes including appetite *** results highlight that GMF could be necessary for the maintenanee of energy homeostasis in insects.

关键词： appetite body weight feeding behavior geomagnetic field magnetoreception Nilaparvata lugens

Oxygen vacancies enriched Ir/WOx catalysts for the directly chem-catalytic conversion of cellulose to ethanol

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Tungsten 2025年第1期7卷 88-99页

作者： yu-jing Weng zhao-Ying Ding Ying-Chao Li yuan-Feng Wu yuan-Yang Xu Rui Chen Xiao-Lei zhao Hai-Yong Wang Da-Lei Zhang yu-Long Zhang Henan Key Laboratory of Coal Green Conversion and International Joint Laboratory of Coal Clean Utilization College of Chemistry and Chemical Engineering Henan Polytechnic University Key Laboratory of Renewable Energy Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Liaoning Institute of Energy Technology

Tungsten and its oxides are highly versatile catalysts with unique properties that hold great promise for a wide array of applications,including biological pathways and chemical *** chemo-catalysis of cellulose to ethanol presents a promising avenue for ethanol synthesis with the potential for enhanced efficiency compared to conventional methods,offering a sustainable and carbon-neutral alternative to existing petrochemical and biological ***,Ir/WOxcatalysts enriched with oxygen vacancies were meticulously prepared and demonstrated remarkable catalytic performance in converting cellulose to ethanol directly in the presence of tungstic *** catalyst achieved a high ethanol yield of 66.5%under optimal reaction conditions,approaching the theoretical yield limit of traditional ethanol *** results revealed the presence of oxygen defects,Bronsted/Lewis acidity,and Ir nanoclusters on the catalyst surface,working synergistically to facilitate the cascade catalysis of cellulose hydrolysis,sugar retro-aldol condensation reaction,and C2 intermediate hydrodeoxygenation to *** situ Fourier transform infrared spectrometer analysis confirmed the catalyst's ability to enhance the adsorption and activation of ethylene glycol for ethanol *** manipulating subtle structural features,this study offers a fresh perspective on tungsten group catalyst design and underscores the importance of synergistic effects among catalytic sites for the efficient production of ethanol from cellulose.

关键词： Cellulosic ethanol Chem-catalysis Hydrogenolysis Retro-aldol condensation Tungsten