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Crystal Structure of a Linear Ag(I) Complex with Niflumic Acid and Its Fluorescent Property

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1387-1391页

作者： tan Yu-hui YANG Shao-Ping LI Qing-Song tan Yu-Li Department qf Pharmacy Gannan Medical University Ganzhou Jiangxi 341000 China Tianxin Hospital of Zhuzhou Zhuzou Hzman 412001 China

A novel Ag（1） complex AgH（Nifa）2 1 （C26H17AgF6N4O4, Mr = 671.31） was synthesized through hydrothermal reaction of Ag2SO4 and Niflumic acid （HNifa）, and characterized by single-crystal X-ray determination, IR and fluorescent spectra. Crystal data for 1： monoclinic, space group C2/c, with a = 9.5446（16）, b = 12.3203（16）, c = 21.056 （3） A, β = 98.075（2）°, V= 2451.5（6） A^3, T = 293（2） K, Z = 4, D,. = 1.819 g/cm^3, F（000） = 1336,μ = 0.912 mm^-1, S = 1.001, （△ρ）min = 0.849, the final R = 0.0391 and wR = 0.1286. The local geometry around the central metal AgO） ion is linear. Two carboxylic acids of neighboring ligands sharing one hydrogen atom by two hydrogen bonds result in the formation of an infinite hydrogen-bonded chain. Solid-state fluorescence of I at room temperature shows that the maximal emission peak occurs in 439 nm.

关键词： niflumic acid silver(Ⅰ) complex hydrothermal synthesis fluorescence

Strong invariance principle for a counterbalanced random walk

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 370-380页

作者： tan hui-qun HU Zhi-shui DONG Liang International Institute of Finance School of ManagementUniversity of Science and Technology of ChinaHefei 230026China Center for Basic Teaching and Experiment Nanjing University of Science and TechnologyJiangyin 214443China

We study a counterbalanced random walkS_(n)=X_(1)+…+X_(n),which is a discrete time non-Markovian process andX_(n) are given recursively as *** n≥2,X_(n) is a new independent sample from some fixed law̸=0 with a fixed probability p,andX_(n)=−X_(v(n))with probability 1−p,where v(n)is a uniform random variable on{1;…;n−1}.We apply martingale method to obtain a strong invariance principle forS_(n).

关键词： random walk martingale invariance principle

Deformation and Motion of a Red Blood Cell in a Shear Flow Simulated by a Lattice Boltzmann Model

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Communications in Theoretical Physics 2009年第6期51卷 1117-1120页

作者： SHI Juan QIU Bing tan hui-Li School of Information and Communication Engineering Guilin University of Electronic Technology Guilin 541004 China College of Physics and Electronic Engineering Guangxi Normal University Guilin 541004 China

A lattice Boltzmann model is presented to simulate the deformation and motions of a red blood cell （RBC） in a shear flow. The curvatures of the membrane of a static RBC with different chemical potentiM drops calculated by our model agree with those computed by a shooting method very well. Our simulation results show that in a shear flow, biconcave RBC becomes highly flattened and undergoes tank-treading motion. With intrinsically parallel dynamics, this lattice Boltzmann method is expected to find wide applications to both single and multi-vesicles suspension as well as complex open membranes in various fluid flows for a wide range of Reynolds numbers.

关键词： red blood cells biconcave lattice Boltzmann method

Seismic wave input method for three-dimensional soil-structure dynamic interaction analysis based on the substructure of artificial boundaries

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Earthquake Engineering and Engineering Vibration 2019年第4期18卷 747-758页

作者： Liu Jingbo tan hui Bao Xin Wang Dongyang Li Shutao Department of Civil Engineering Tsinghua University

The method of inputting the seismic wave determines the accuracy of the simulation of soil-structure dynamic interaction. The wave method is a commonly used approach for seismic wave input, which converts the incident wave into equivalent loads on the cutoff boundaries. The wave method has high precision, but the implementation is complicated, especially for three-dimensional models. By deducing another form of equivalent input seismic loads in the fi nite element model, a new seismic wave input method is proposed. In the new method, by imposing the displacements of the free wave fi eld on the nodes of the substructure composed of elements that contain artifi cial boundaries, the equivalent input seismic loads are obtained through dynamic analysis of the substructure. Subsequently, the equivalent input seismic loads are imposed on the artifi cial boundary nodes to complete the seismic wave input and perform seismic analysis of the soil-structure dynamic interaction model. Compared with the wave method, the new method is simplifi ed by avoiding the complex processes of calculating the equivalent input seismic loads. The validity of the new method is verifi ed by the dynamic analysis numerical examples of the homogeneous and layered half space under vertical and oblique incident seismic waves.

关键词： soil-structure dynamic interaction seismic wave input wave method equivalent input seismic loads substructure of artifi cial boundaries

Theoretical analysis of JMC effect on stress wave transmission and reflection

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International Journal of Minerals,Metallurgy and Materials 2018年第11期25卷 1237-1245页

作者： Xin Chen Mei-feng Cai Jian-chuan Li Wen-hui tan Beijing Key Laboratory of Urban Underground Space Engineering University of Science and Technology Beijing Civil and Resource Engineering School University of Science and Technology Beijing Institute of Underground Space Technology School of Civil EngineeringSoutheast University

Taking the joint matching coefficient(JMC) which represents the contact area ratio of the joint in rock masses as the key parameter, a one-dimensional contacted interface model(CIM-JMC) was established in this study to describe the wave propagation across a single joint. According to this model, the reflected and transmitted waves at the joint were obtained, and the energy coefficients of reflection and transmission were calculated. Compared with the modified Split Hopkinson pressure bar(SHPB) experiment, it was validated by taking the incident wave of the SHPB test as the input condition in the CIM-JMC, and the reflected and transmitted waves across the joint were calculated by the model. The effects of four sets of JMCs(0.81, 0.64, 0.49, and 0.36) on the transmission and reflection of the stress wave propagation across the joint were analyzed and compared with the experimental results. It demonstrated that the values of CIM-JMC could represent both the transmission and reflection of the stress wave accurately when JMC > 0.5, but could relatively accurately represent the reflection rather than the transmission when JMC 0.5.

关键词： joint matching coefficient stress wave transmission reflection energy coefficient rock dynamics

Ga-based liquid metal as an extreme pressure lubricant for steel-ceramic pairs

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Science China(Technological Sciences) 2022年第5期65卷 1107-1115页

作者： YANG DongSheng CHEN WenYuan CHEN Jiao SUN QiChun tan hui CHENG Jun State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China

Extreme pressure lubrication is a crucial engineering problem for many mechanical ***,an extraordinary and novel functional material,Ga-based liquid metal(GLM),is found to be a promising extreme pressure lubricant for steel-ceramic sliding pairs and bears applied load above 1500 N.A Ga-rich metallic tribofilm forms on the frictional interface during sliding,providing good lubricity and bearing *** addition,the lubrication performance of GLM strongly depends on its composition and the contacting *** Ga-In-Sn alloy has superior lubrication to binary Ga-In *** lubrication is more effective on the interfaces of AISI52100/Si_(3)N_(4)than on those of AISI52100/SiC sliding pairs.

关键词： liquid metal sliding wear tribochemistry boundary lubrication

Audio Segmentation via the Similarity Measure of Audio Feature Vectors

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Wuhan University Journal of Natural Sciences 2005年第5期10卷 833-837页

作者： CHEN Gang tan hui CHEN Xin-meng School of Computer Wuhan University Wuhan 430072 Hubei China

A formula to compute the similarity between two audio feature vectors is proposed, which can map arbitrary pair of vectors with equivalent dimension to [0,1）. To fulfill the task of audio segmentation, a self-similarity matrix is computed to reveal the inner structure of an audio clip to be segmented. As the final result must be consistent with the subjective evaluation and be adaptive to some special applications, a set of weights is adopted, which can be modified through relevance feedback techniques. Experiments show that satisfactory result can be achieved via the algorithm proposed in this paper.

关键词： audio segmentation abrupt change detection overall error similarity measure self-similarity matrix relevance feedback

Nitrogenation of Amides via C–C and C–N Bond Cleavage

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CCS Chemistry 2023年第5期5卷 1061-1068页

作者： Ming-hui Zhu Zengrui Cheng Jialiang Wei hui tan Ning Jiao State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191 State Key Laboratory of Organometallic Chemistry Sciences Chinese Academy of SciencesShanghai 200032

Amides are among the fundamental chemicals in organic *** to other carbonyl functional groups,the transformation of amide is relatively difficult and remains a *** traditional deconstruction transformations of amides to other functional products are usually limited to twisted or electronically activated ***,we describe a direct nitrogenation approach to convert amides into *** chemistry provides a novel amide transformation pathway via both C–C and C–N bond ***,the simple,readily available,and inexpensive inorganic salt NaNO2 is successfully employed as a nitrogen source in this organic N-incorporation *** of this study are demonstrated through the latestage modification of drug and natural product derivatives.

关键词： amide activation C–C cleavage C–N cleavage nitrogenation nitriles synthesis

Photoinduced C--C Bond Cleavage and Oxidation of CycloketoximeEsters

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Chinese Journal of Chemistry 2018年第11期36卷 995-999页

作者： Binlin Zhao hui tan Cheng Chen Ning Jiao Zhuangzhi Shi State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Nanjing University Nanjing Jiangsu 210093 China State Key Laboratory of Natural and Biomimetic Drugs School of Phar-maceutical Sciences Peking University Xue Yuan Road 38 Beijing100191 China

A novel structural reorganization of cycloketoxime esters beyond the traditional Beckmann rearrangement process has been established to build cyano‐containing ketones in the presence of photocatalyst. This novel transformation is remarkable with selective C—C bond cleavage and an oxidation process enabled by DMSO used as the solvent, oxidant, and oxygen source avoiding acid, base and toxic cyanide salts as the cyano source. Further applications in late‐stage modification of complex and chiral molecules have also been reported.

关键词： C—C activation radical cycloketoxime oxygenation photocatalysis DMSO