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Tungsten 2025年第1期 80-87页

作者： Fang-Qian Wang Yin Zhang wei-wei Wang Mei-Qian Fu Hong-Bing Mo wei-Dong yu Chao Liu Jun Yan College of Chemistry and Chemical Engineering Central South University Junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

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Preliminary studies of constructing a tissue-engineered lamellar corneal graft by culturing mesenchymal stem cells onto decellularized corneal matrix

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International Journal of Ophthalmology(English edition) 2021年第1期14卷 10-18页

作者： yu-Jie Cen De-Bo You wei Wang yun Feng Department of Ophthalmology Peking University Third HospitalBeijing 100191China Beijing Key Laboratory of Restoration of Damaged Ocular Nerve Peking University Third HospitalBeijing 100191China

AIM:To construct a competent corneal lamellar substitute in order to alleviate the shortage of human corneal ***:Rabbit mesenchymal stem cells(MSCs)were isolated from bone marrow and identified by flow cytometric,osteogenic and adipogenic *** decellularized corneal matrix(XDCM)was generated from dog *** were seeded and cultured on XDCM to construct the tissueengineered ***-transplantation biocompatibility of engineered corneal graft were tested by animal *** were divided into two groups then underwent lamellar keratoplasty(LK)with different corneal grafts:1)XDCM group(n=5):XDCM;2)XDCM-MSCs groups(n=4):tissue-engineered cornea made up with XDCM and *** ocular surface recovery procedure was observed while corneal transparency,neovascularization and epithelium defection were measured and *** vivo on focal exam was performed 3 mo ***:Rabbit MSCs were isolated and *** cytometry demonstrated isolated cells were CD90 positive and CD34,CD45 *** and adipogenic induction verified their multipotent ***-XDCM grafts were constructed and *** vivo transplantation showed the neovascularization in XDCMMSC group was much less than that in XDCM group ***-transplant 3-month confocal test showed less nerve regeneration and bigger cell-absent area in XDCM-MSC ***:This study present a novel corneal tissue-engineered graft that could reduce post-operatively neovascularization and remain transparency,meanwhile shows that co-transplantation of MSCs may help increase corneal transplantation successful rate and enlarge the source range of corneal substitute to overcome cornea donor shortage.

关键词： mesenchymal stem cells xenogenic decellularized corneal matrix acellular corneal matrix neovascularization tissue-engineered cornea

Synthesis of Alkoxysilanes Bearing β-Diketone Group through Hydrosilylation

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Chinese Chemical Letters 2002年第2期13卷 121-122页

作者： yuan YAO wei HUANG Ying HUANG yun Zhao yu The Center of Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing 100080

Alkoxysilane bearing diketone group was synthesized by hydrosilylation of 3-allyl acetylacetone. It was indicated by the 1H NMR spectrum that the C=O group does not interfere with the synthesis.

关键词： Tydrosilylation alkoxysilane b-diketone.

Software Defect Prediction Method Based on Stable Learning

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Computers, Materials & Continua 2024年第1期78卷 65-84页

作者： Xin Fan Jingen Mao Liangjue Lian Li yu wei Zheng yun Ge College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing210012China School of Software Nanchang Hangkong UniversityNanchang330029China Software Testing and Evaluation Center Nanchang Hangkong UniversityNanchang330029China

The purpose of software defect prediction is to identify defect-prone code modules to assist software quality assurance teams with the appropriate allocation of resources and *** previous software defect prediction studies,transfer learning was effective in solving the problem of inconsistent project data ***,target projects often lack sufficient data,which affects the performance of the transfer learning *** addition,the presence of uncorrelated features between projects can decrease the prediction accuracy of the transfer learning *** address these problems,this article propose a software defect prediction method based on stable learning(SDP-SL)that combines code visualization techniques and residual *** method first transforms code files into code images using code visualization techniques and then constructs a defect prediction model based on these code *** the model training process,target project data are not required as prior *** the principles of stable learning,this paper dynamically adjusted the weights of source project samples to eliminate dependencies between features,thereby capturing the“invariance mechanism”within the *** approach explores the genuine relationship between code defect features and labels,thereby enhancing defect prediction *** evaluate the performance of SDP-SL,this article conducted comparative experiments on 10 open-source projects in the PROMISE *** experimental results demonstrated that in terms of the F-measure,the proposed SDP-SL method outperformed other within-project defect prediction methods by 2.11%-44.03%.In cross-project defect prediction,the SDP-SL method provided an improvement of 5.89%-25.46% in prediction performance compared to other cross-project defect prediction ***,SDP-SL can effectively enhance within-and cross-project defect predictions.

关键词： Software defect prediction code visualization stable learning sample reweight residual network

Social bots and mass media manipulated public opinion through dual opinion climate

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Chinese Physics B 2022年第1期31卷 686-691页

作者： Chun Cheng yun Luo Chang-bin yu wei-ping Ding School of Information Science and Technology Nantong UniversityNantong 226019China School of Computer Science and Technology Zhejiang UniversityHangzhou 310024China School of Engineering Westlake UniversityHangzhou 310024China

Opinion dynamics models based on the multi-agent method commonly assume that interactions between individuals in a social network result in changes in their ***,formation of public opinion in a social network is a macroscopic statistical result of opinions of all expressive individuals(corresponding to silent individuals).Therefore,public opinion can be manipulated not only by changing individuals'opinions,but also by changing their states of expression(or silence)which can be interpreted as the phenomenon"spiral of silence"in social *** on this theory,we establish a"dual opinion climate"model,involving social bots and mass media through a multi-agent method,to describe mechanism for manipulation of public opinion in social *** find that both social bots(as local variables)and mass media(as a global variable)can interfere with the formation of public opinion,cause a significant superposition effect when they act in the same direction,and inhibit each other when they act in opposite directions.

关键词： public opinion social bots mass media spiral of silence

Petrography and origin of the Lower Ordovician microbial carbonates in the Songzi Area of Hubei Province,middle Yangtze region,China

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Petroleum Science 2019年第5期16卷 956-971页

作者： Chuan-Tao Xiao Guo-Qi wei Zhen-yu Song yun-Peng Xiao wei Yang Man Dong yun-Fei Huang Da Gao Geosciences School of Yangtze University Wuhan 430100HubeiChina Research Institute of Petroleum Exploration and Development PetroChinaLangfang 065007HebeiChina

This study is the first systematic assessment of the Lower Ordovician microbial carbonates in Songzi,Hubei Province,*** paper divides the microbial carbonates into two types according to growth patterns,namely nongranular and *** nongranular types include stromatolites,thrombolites,dendrolites,leiolites and laminites;the granular types are mainly oncolites and may include a small amount of microbiogenic *** to their geometric features,the stromatolites can be divided into four types:stratiform,wavy,columnar and ***,dipyramidal columnar stromatolites are identified for the first time and represent a new type of columnar *** thrombolites are divided into three types:speckled,reticulated and *** grazing gastropod Ecculiomphalus and traces of bioturbation are observed in the speckled and reticulated *** paper considers these two kinds of thrombolites to represent bioturbated *** findings not only fill gaps in the field of domestic Ordovician bioturbated thrombolites but also provide new information for the study of *** on the analysis of the sedimentary characteristics of microbialites,the depositional environments of the various types of microbialites are described,and the distribution patterns of their depositional environments are *** relationship between the development of microbialites and the evolution and radiation of metazoans during the Early to Middle Ordovician is *** with the correspondence between the stepwise and rapid radiation of metazoans and the abrupt reduction in the number of microbialites between the late Early Ordovician and the early Middle Ordovician,fossils of benthonic grazing gastropods(Ecculiomphalus)were found in the stromatolites and thrombolite of the study *** is believed that the gradual reduction in microbialites was related to the rapid increase in the abundance of *** not only graze

关键词： Microbial carbonate Stromatolites Thrombolites Oncolite Lower Ordovician Songzi Area

Testing the distance-duality relation with data from galaxy clusters and type Ia supernovae

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Research in Astronomy and Astrophysics 2011年第8期11卷 895-901页

作者： Xiang-yun Fu Pu-Xun Wu Hong-wei yu Zheng-Xiang Li Institute of Physics Hunan University of Science and Technology Xiangtan 411201 China Center for Nonlinear Science and Department of Physics Ningbo University Ningbo 315211 China Department of Physics and Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education Hunan Normal University Changsha 410081 China

We test the distance-duality （DD） relation by combining the angular diameter distance DA provided by two galaxy cluster samples compiled by De Filippis et al. （the elliptical β model） and Bonamente et al. （the spherical β model）, and the luminosity distance DL from Constitution and Union2 type Ia supernova （SNe Ia） datasets. To obtain DL associated with the observed DA at the same redshift, we smooth the noise of the SNe Ia in a model-independent way, obtain the evolutionary curve of DL and, finally, test the DD relation. We find that the elliptical β model, when compared with the SNe Ia from the Constitution compilation, is only consistent with the DD relation at the 3σ confidence level （CL）, while the spherical β model is incompatible with the DD relation at the 3σ CL. For the Union2 compilation, the De Filippis and Bonamente samples are marginally compatible with the validity of the DD relation at the 1σ and 2σ CLs, respectively.

关键词： galaxies: distances and redshifts -- galaxies: clusters: general -- super- novae: general

A new C_(21) steroid glycoside from Marsdenia tenacissima

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Chinese Chemical Letters 2008年第4期19卷 444-446页

作者： Jing Liu Zhi Bin yu yun Hua Ye Ya wei Zhou Bescholar Research Center of Peking University Beijing 100084China The Key Laboratory of Bioorganic Chemistry and Molecular Engineering Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

A new C21 steroid glycoside,11α-O-tigloyl-12-β-O-acetyl tenacigenin B 3-O-β-D-glucopyranosyl-（1→4）-β-D-glucopyr- anosyl-（1→4）-3-O-methyl-6-deoxy-β-D-allopyranosyl-（1→4）-β-D-oleandropyranoside（1）,named tenacissoside N was isolated from the stems of Marsdenia *** structure of the glycoside was identified by HR-ESI-MS and NMR spectra.

关键词： Marsdenia tenacissima Tenacissoside N

Multi-domain equivalent method for prediction of elastic modulus of complex fractured rock mass

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Journal of Mountain Science 2023年第3期20卷 859-872页

作者： JIAO Feng-yu WANG Hui-dong LI Tuo CHEN yun MA Guo-wei School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China Tianjin Key Laboratory of Prefabricated Building and Intelligent Construction Hebei University of TechnologyTianjin 300401China

Reliable estimation of deformation and failure behaviors of fractured rock mass is important for practical engineering *** study proposes a multi-domain equivalent method for fracture network to estimate the deformation properties of complex fractured rock *** comprehends both the advantages of the discrete fracture network model and the equivalent continuum model to capture the features of discontinuities explicitly while reducing computational *** complex fracture network is stochastically split into a number of subfracture networks according to the domain,length or *** analytical solution is derived to infer theoretically the relationship between the elastic moduli of the original complex fractured rock mass and the split subfractured rock masses by introducing a correction term based on the deformation superposition *** simulations are conducted to determine the elastic moduli of split subfractured rock masses using universal distinct element code(UDEC),while the elastic modulus of the original model is estimated based on the currently proposed analytical *** results show that the estimation accuracy with the current domainbased splitting model is far superior compared to those with the other two splitting ***,the estimation method of elastic modulus of complex fractured rock mass based on domain splitting mode of fracture network is identified as the multi-domain equivalent method proposed in this *** reliability of this method is evaluated,and its high computational efficiency is demonstrated through exemplification with regard to different geometric configurations for stochastically artificial discrete fracture *** proposed multi-domain equivalent method constructs the theoretical framework except for the regression analysis hypothesis compared to the density-reduced model equivalent method.

关键词： Fractured rock masses Discrete fracture network Rock mass deformability Multi-domain equivalent method

The Consistency of LSE Estimators in Partial Linear Regression Models under Mixing Random Errors

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1244-1272页

作者： yun Bao YAO yu Tan LÜ Chao LU wei WANG Xue Jun WANG School of Mathematical Sciences Anhui UniversityHefei 230601P.R.China School of Big Data and Artificial Intelligence Chizhou UniversityChizhou 247000P.R.China School of Big Data and Statistics Anhui UniversityHefei 230601P.R.China

In this paper,we consider the partial linear regression model y_(i)=x_(i)β^(*)+g(ti)+ε_(i),i=1,2,...,n,where(x_(i),ti)are known fixed design points,g(·)is an unknown function,andβ^(*)is an unknown parameter to be estimated,random errorsε_(i)are(α,β)-mix_(i)ng random *** p-th(p>1)mean consistency,strong consistency and complete consistency for least squares estimators ofβ^(*)and g(·)are investigated under some mild *** addition,a numerical simulation is carried out to study the finite sample performance of the theoretical ***,a real data analysis is provided to further verify the effect of the model.

关键词： (α,β)-mixing random variables partial linear regression model least squares estimator consistency