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Chinese Journal of Structural Chemistry 2019年第12期38卷 2155-2160页

作者： WANG Xiu-Yan LI Cong ZOU Chun-Kai kan ruo-fei ZHANG Xiao-Xu XU Zhan-Lin Key Laboratory of Preparation and Applications of Environmental Friendly Materials Jilin Normal UniversitySiping 136000China Department of Chemistry Jilin Normal UniversitySiping 136000China

A new Co（Ⅱ） coordination polymer, [Co（1,4-chdc）（L）（H2O）]n（1）, was synthesized under hydrothermal condition（1,4-H2chdc = 1,4-cyclohexanedicarboxylic acid, L = 2-（4-fluoro-phenyl）-1 H-imidazo[4,5-f][1,10]phenanthroline）. Its crystal structure was determined by single-crystal X-ray diffraction. 1 crystallizes in triclinic, space group P1 with a = 8.790（5）, b = 10.486（5）, c = 13.305（5） ?, α = 87.391（5）, β = 82.925（5）, γ = 81.841（5）o, V = 1204.2（10） ?3, Z = 2, C27H23FN4O5Co, Mr = 561.42, Dc = 1.548 g/cm3, F（000） = 578, μ（Mo Ka） = 0.769 mm-1, R = 0.0415 and wR = 0.1043. In 1, each 1,4-chdc anion bridges two neighboring Co（Ⅱ） atoms to give a chain structure. The L ligands are attached on one side of the chain through chelating the Co（Ⅱ） atoms, and are stacked with those of an adjacent chain through π-π interactions, yielding a double-chain structure. The double-chain structures are linked into a supramolecular layer structure through N–H···O hydrogen-bonding interactions between the adjacent double-chain structures. Moreover, the thermal behavior of 1 was also studied.

关键词： cobalt coordination polymer 1,4-cyclohexanedicarboxylic acid π-πinteractions hydrogen bond thermal behavior

New triterpenoid saponins from the leaves of Ilex chinensis and their hepatoprotective activity

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Chinese Journal of Natural Medicines 2021年第5期19卷 376-384页

作者： SHAO Si-Yuan LI ruo-fei SUN Hua LI Shuai State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China

Seven new triterpenoid saponins,including five ursane-type saponins,ilexchinenosides R–V(1–5),and two oleananetype saponins,ilexchinenosides W–X(6–7),with four known triterpenoid saponins(8–11)were isolated from the leaves of Ilex *** structures were elucidated by comprehensive spectroscopic 1 D and 2 D NMR and HR-ESI-MS *** sugar moieties were determined by HPLC analysis compared with standards after hydrolysis and *** 1,2,4,9 and 10 exhibited potential hepatoprotective activity against N-acetyl-p-aminophenol(APAP)-induced Hep G2 cell injury in vitro.

关键词： Ilex chinensis Ursane and oleanane Triterpenoid saponins Hepatoprotective activity

Synthesis and electrochemical properties of 2,6-bis(6-aryl-[1,2,4]- triazolo[3,4-b][1,3,4]-thiadiazole-3-yl)pyridines

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Chinese Chemical Letters 2007年第5期18卷 505-508页

作者： Chun Xia Tan ruo fei Feng Xiao Xia Peng The College of Traditional Medicine of Gansu Lanzhou 730030 China Life Science ＆ Engineering College Northwest University for Nationalities Lanzhou 730030 China

By the condensation of 2,6-bis（4-amino-5-mercapto-[1,2,4]-triazoles-2）pyridine with aromatic acid in the presence of phosphorus oxychloride. Compounds of 2,6-bis（6-aryl-[1,2,4]-triazolo[3,4-b][1,3,4]-thiadiazole-3-yl）pyridines were synthesized. Their structures were confirmed by IR, ^1H NMR spectroscopies and elemental analysis. Their electrochemical behavior and cyclic voltammogram also were be studied. The results showed that they have high ionization potentials and good affinity.

关键词： Synthesis Triazolo-thiadiazoles Electrochemical properties

Multiuser beamforming based on max SINR for downlink spatial multiplexing MIMO

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 28-33页

作者： MA Peng-fei ZHENG kan WANG Wen-bo Wireless Signal Processing and Network Laboratory Beijing University ofPosts and Telecommunications Beijing 100876 China

In this article, a method based on max signal interference noise ratio（SINR） criterion is proposed, to mitigate the interuser interference for downlink multiuser spatial multiplexing multi-input multi-output（MIMO） systems. Unlike the zero forcing （ZF） scheme in which the SNR is decreased when the interference is eliminated completely, max SINR method makes a compromise between noise and interuser interference. When the number of substreams is larger than the difference between the number of base station antennas and the sum of interference mobile station antennas, the ZF is infeasible An existing coordinated TX-RX block diagonalization（COOR BD） method uses preprocessing at the receiver to cancel the interuser interference. However, it cannot obtain more receive diversity gain because of the preprocessing. Analysis and simulation show that the max SINR scheme has better performance than the ZF method. Moreover, when the ZF is infeasible, the max SINR scheme can obtain more receive diversity gain than COOR BD in the two-user case.

关键词： array signal processing beamforming MIMO systems spatial multiplexing

Preparation of AlN thin films for film bulk acoustic resonator application by radio frequency sputtering

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第3期10卷 464-470页

作者： kan LI Hao JIN De-miao WANG Yi-fei TANG Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

Aluminum nitride （AlN） thin films with high c-axis orientation have been prepared on a glass substrate with an Al bottom electrode by radio frequency （RF） reactive magnetron sputtering. Based on the analysis of Berg＇s hysteresis model, the improved sputtering system is realized without a hysteresis effect. A new control method for rapidly depositing highly c-axis oriented AlN thin films is proposed. The N2 concentration could be controlled by observing the changes in cathode voltage, to realize the optimum processing condition where the target could be fixed stably in the transition region, and both stoichiometric film composition and a high deposition rate could be obtained. Under a 500 W RF power of a target with a 6 cm diameter, a substrate temperature of 450 ℃, a target-substrate distance of 60 mm and a N2 concentration of 25%, AlN thin film with preferential （002） orientation was deposited at 2.3 μm/h which is a much higher rate than previously achieved. Through X-ray diffraction （XRD） analysis, the full width at half maximum （FWHM） of AlN （002） was shown to be about 0.28°, which shows the good crystallinity and crystal orientation of AlN thin film. With other parameters held constant, any increase or decrease in N2 concentration results in an increase in the FWHM of AlN.

关键词： Aluminum nitride (A1N) Piezoelectric thin film Radio frequency (RF) reactive sputtering Preferred orientation,Film bulk acoustic resonator (FBAR)

Single-cell analysis identifies phospholysine phosphohistidine inorganic pyrophosphate phosphatase as a target in ulcerative colitis

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World Journal of Gastroenterology 2023年第48期29卷 6222-6234页

作者： Yan-fei Wang ruo-Yu He Chan Xu Xiao-Ling Li Yan-fei Cao Department of Gastroenterology The Third Affiliated Hospital of Zhejiang Chinese Medical UniversityNo.219 Moganshan RoadXihu DistrictHangzhou 310005Zhejiang ProvinceChina Clinical laboratory The Third Affiliated Hospital of Zhejiang Chinese Medical UniversityNo.219 Moganshan RoadXihu DistrictHangzhou 310005Zhejiang ProvinceChina Elder Medicine Department The Third Affiliated Hospital of Zhejiang Chinese Medical UniversityNo.219 Moganshan RoadXihu DistrictHangzhou 310005Zhejiang ProvinceChina

BACKGROUND Ulcerative colitis(UC)is a chronic gastrointestinal disorder characterized by inflammation and ulceration,representing a significant predisposition to colorectal *** advances in single-cell RNA sequencing(scRNA-seq)technology offer a promising avenue for dissecting the complex cellular interactions and molecular signatures driving UC *** To utilize scRNA-seq technology to dissect the complex cellular interactions and molecular signatures that underlie UC *** In this research,we integrated and analyzed the scRNA-seq data from UC ***,we conducted mRNA and protein level assays as well as pathology-related staining tests on clinical patient *** In this study,we identified the sustained upregulation of inflammatory response pathways during UC progression,characterized the features of damaged endothelial cells in ***,we uncovered the downregulation of phospholysine phosphohistidine inorganic pyrophosphate phosphatase(LHPP)has a negative correlation with signal transducer and activator of transcription *** downregulation of LHPP in UC patient tissues and plasma suggests that LHPP may serve as a potential therapeutic target for *** paper highlights the importance of LHPP as a potential key target in UC and unveils its potential role in inflammation *** The findings suggest that LHPP may serve as a potential therapeutic target for UC,emphasizing its importance as a potential key target in UC and unveiling its role in inflammation regulation.

关键词： Ulcerative colitis Single-cell RNA sequencing Phospholysine phosphohistidine inorganic pyrophosphate phosphatase

A fast and efficient mesh segmentation method based on improved region growing

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Applied Mathematics(A Journal of Chinese Universities) 2014年第4期29卷 468-480页

作者： YANG fei ZHOU Fan WANG ruo-mei LIU Li LUO Xiao-nan School of Information Science and Technology Sun Yat-sen University National Engineering Research Center of Digital Life

Mesh segmentation is one of the important issues in digital geometry processing. Region growing method has been proven to be a efficient method for 3D mesh segmentation. However, in mesh segmentation, feature line extraction algorithm is computationally costly, and the over-segmentation problem still exists during region merging processing. In order to tackle these problems, a fast and efficient mesh segmentation method based on improved region growing is proposed in this paper. Firstly, the dihedral angle of each non-boundary edge is defined and computed simply, then the sharp edges are detected and feature lines are extracted. After region growing process is finished, an improved region merging method will be performed in two steps by considering some geometric criteria. The experiment results show the feature line extraction algorithm can obtain the same geometric information fast with less computational costs and the improved region merging method can solve over-segmentation well.

关键词： mesh segmentation feature line region growing dihedral angle.

Bayesian Reliability Modeling and Assessment Solution for NC Machine Tools under Small-sample Data

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Chinese Journal of Mechanical Engineering 2015年第6期28卷 1229-1239页

作者： YANG Zhaojun kan Yingnan CHEN fei XU Binbin CHEN Chuanhai YANG Chuangui College of Mechanical Science and Engineering Jilin University Key Laboratory of CNC Equipment Reliability Technique of Machinery Industry Jilin University

Although Markov chain Monte Carlo（MCMC） algorithms are accurate, many factors may cause instability when they are utilized in reliability analysis; such instability makes these algorithms unsuitable for widespread engineering applications. Thus, a reliability modeling and assessment solution aimed at small-sample data of numerical control（NC） machine tools is proposed on the basis of Bayes theories. An expert-judgment process of fusing multi-source prior information is developed to obtain the Weibull parameters＇ prior distributions and reduce the subjective bias of usual expert-judgment methods. The grid approximation method is applied to two-parameter Weibull distribution to derive the formulas for the parameters＇ posterior distributions and solve the calculation difficulty of high-dimensional integration. The method is then applied to the real data of a type of NC machine tool to implement a reliability assessment and obtain the mean time between failures（MTBF）. The relative error of the proposed method is 5.8020×10-4 compared with the MTBF obtained by the MCMC algorithm. This result indicates that the proposed method is as accurate as MCMC. The newly developed solution for reliability modeling and assessment of NC machine tools under small-sample data is easy, practical, and highly suitable for widespread application in the engineering field; in addition, the solution does not reduce accuracy.

关键词： NC machine tools reliability Bayes mean time between failures(MTBF) grid approximation Markov chain Monte Carlo(MCMC)

Study of ss-DNA Adsorption and Nano-mechanical Properties on Mica Substrate with Surface Forces Apparatus

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Chinese Journal of Mechanical Engineering 2018年第5期31卷 91-98页

作者： Gui-Bin Shen Ya-Jing kan Min-Hua Chen Yun-fei Chen Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments Southeast University Nanjing 211189 China School of Mechanical Engineering Southeast University Nanjing 211189 China

Many DNA?based devices need to build stable and controllable DNA films on surfaces. However, the most com?monly used method of film characterization, namely, the probe?like microscopes which may destroy the sample and substrate. Surface Forces Apparatus(SFA) technique, specializing in surface interaction studies, is introduced to investigate the e ects of DNA concentration on the formation of single?stranded DNA(ss?DNA) film. The result demonstrates that 50 ng/μL is the lowest concentration that ss?DNA construct a dense layer on mica. Besides, it is also indicated that at di erent DNA concentrations, ss?DNA exhibit diverse morphology: lying flat on surface at 50 ng/μL while forming bilayer or cross?link at 100 ng/μL, and these ss?DNA structures are stable enough due to the repeatabil?ity even under the load of 15 mN/m. At the same time, an obvious adhesion force is measured:/m at 100 ng/μL, respectively, which is attributed to the ion?correlation e ect. M-6.5 mN/m at 50 ng/μL and-5.3 mNoreover, the atomic force microscopy(AFM) images reveal the entire surface is covered with wormlike ss?DNA and the measured surface roughness(1.8±0.2 nm) also matches well with the film thickness by SFA. The desorption behaviors of ss?DNA layer from mica surface occur by adding sodium salt into gap bu er, which is mainly ascribed to the decreased ion?ion cor?relation force. This paper employing SFA and AFM techniques to characterize the DNA film with flexibility and stable mechanical ability achieved by ion bridging method, is helpful to fabricate the DNA?based devices in nanoscale.

关键词： Single?stranded DNA Adsorption Nano?mechanical properties Ion?correlation effect Surface forces apparatus

SP3-coupled global variance reduction method based on RMC code

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Nuclear Science and Techniques 2021年第11期32卷 42-51页

作者： Qing-Quan Pan Teng-fei Zhang Xiao-Jing Liu Hui He kan Wang School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Department of Engineering Physics Tsinghua UniversityBeijing 100084Chin

A global variance reduction(GVR)method based on the SPN method is ***,the global multi-group cross-sections are obtained by Monte Carlo(MC)global ***,the SP3 equation is solved to obtain the global flux ***,the global weight windows are approximated by the global flux distribution,and the GVR simulation is *** GVR method is implemented as an automatic process in the RMC *** SP3-coupled GVR method was tested on a modified version of C5 G7 benchmark with a thickened water *** results show that the SP3-coupled GVR method can improve the efficiency of MC criticality calculation.

关键词： RMC code Global homogenization Variance reduction SPN theory