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Experimental and Theoretical Study of Reactions between Manganese Oxide Cluster Cations and Hydrogen Sulfide

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Chinese Journal of Chemical Physics 2013年第6期26卷 679-686,I0003,I0004页

作者： Mei-ye Jia Sheng-gui He mao-fa ge Beijing National Laboratory for Molecular Sciences (BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Manganese oxide cluster cations Mnm180n＋ were prepared by laser ablation and reacted with hydrogen sulfide （H2S） in a fast flow reactor under thermal collision conditions. A time-of-flight mass spectrometer was used to detect the cluster distributions before and after the interactions with H2S. The experiments suggest that oxygen-for-sulfur （O/S） ex- change reaction to release water took place in the reactor for most of the manganese oxide cluster cations： MnmlSOn＋＋H2S→Mnm18On-1S＋＋H218O. Density functional theory cal- culations were performed for reaction mechanisms of Mn202＋＋H2S, Mn203＋＋H2S, and Mn204＋＋H2S. The computational results indicate these O/S exchange reactions are both thermodynamically and kinetically favorable, thus in good agreement with the experimental observations. The O/S exchange reactions identified in this gas-phase cluster study parallel similar behavior of related condensed phase reaction systems.

关键词： Cluster Oxygen-for-sulfur exchange Reaction mechanism Mass spectrometry Density functional theory

Area Operators on Bergman Spaces

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1161-1176页

作者： Xiao Fen LV Jordi PAU mao fa WANG Department of Mathematics Huzhou UniversityHuzhou 313000P.R.China Departament de Matemàtiques i Informàtica Universitat de Barcelona08007 BarcelonaCataloniaSpain School of Mathematics and Statistics Wuhan UniversityWuhan 430072P.R.China

We completely characterize the boundedness of area operators from the Bergman spaces A_(α)^(p)(Bn)to the Lebesgue spaces L^(q)(S_(n))for all 0 详细信息

We completely characterize the boundedness of area operators from the Bergman spaces A_(α)^(p)(Bn)to the Lebesgue spaces L^(q)(S_(n))for all 0

关键词： Area operator Bergman space tent space area formula

Evaluation of microRNA expression profiles in human sperm frozen using permeable cryoprotectant-free droplet vitrification and conventional methods

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Asian Journal of Andrology 2024年第4期26卷 366-376页

作者： Li-Xin Zhang Jing mao Yan-Dong Zhou Guang-Yao mao Run-fa Guo Hong-Shan ge Xia Chen Department of Histology and Embryology Medical SchoolNantong UniversityNantong 226001China Department of Reproductive Medicine The Affiliated Taizhou People’s Hospital of Nanjing Medical UniversityTaizhou School of Clinical MedicineNanjing Medical UniversityTaizhou 225300China.

For sperm cryopreservation,the conventional method,which requires glycerol,has been used for a long *** addition,the permeable cryoprotectant-free vitrification method has been continuously *** the differences of cryopreservation effects between the two methods have being studied,differences in microRNA(miRNA)profiles between them remain *** this study,we investigated the differences in miRNA expression profiles among conventional freezing sperm,droplet vitrification freezing sperm and fresh human *** also analyzed the differences between these methods in terms of differentially expressed miRNAs(DEmiRs)related to early embryonic development and paternal *** results showed no significant differences between the cryopreservation methods in terms of sperm motility ratio,plasma membrane integrity,DNA integrity,mitochondrial membrane potential,acrosome integrity,and ultrastructural ***,sperm miRNA-sequencing showed differences between the two methods in terms of the numbers of DEmiRs(28 and 19 with vitrification using a nonpermeable cryoprotectant and the conventional method,respectively)in postthaw and fresh sperm *** related to early embryonic development and paternal epigenetics mainly included common DEmiRs between the *** results showed that the differences between conventional freezing and droplet vitrification were minimal in terms of miRNA expression related to embryonic development and *** in sperm miRNA expression due to freezing are not always detrimental to embryonic *** study compared differences in miRNA expression profiles before and after cryopreservation between cryopreservation by conventional and vitrification *** offers a new perspective to evaluate various methods of sperm cryopreservation.

关键词： cryopreservation cryoprotectant-free vitrification early embryonic development paternal epigenetic inheritance sperm miRNAs sucrose

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

Preparation and Structure-Property Regulation Mechanism of Reversible Thermochromic Polydiacetylene

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Chinese Journal of Polymer Science 2024年第8期42卷 1111-1121页

作者： Zhi-Qing ge Shuo Yan Zu-Xiong Pan Shan Lei Xuan-Zhi mao Chu Zhao Mo-Zhen Wang Xue-Wu ge Key Laboratory of Precision and Intelligent Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China Marshall Laboratory of Biomedical Engineering International Cancer CenterLaboratory of Evolutionary Theranostics(LET)School of Biomedical EngineeringShenzhen University Medical SchoolShenzhen UniversityShenzhen 518055China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

The thermochromic mechanism and the structure-property regulation principle of reversible thermochromic polydiacetylene(PDA)materials have always been a challenging *** this work,a series of diacetylene monomers(m-PCDA)containing phenyl and amide or carboxyl groups were synthesized from 10,12-pentacosadiynoic acid(PCDA)through the esterification or amidation *** effects of the number and the distribution of the functional groups in m-PCDA molecules on their solid-state polymerization capability,and the thermochromic mechanism of their corresponding polymers(m-PDA)were investigated and discussed in *** results show that the m-PCDA monomers containing both benzene ring and groups that can form hydrogen bonding interactions have strong intermolecular interaction,and are easy to carry out the solid phase polymerization under 254-nm UV irradiation to obtain the corresponding new thermochromic m-PDA *** thermochromic behavior of m-PDA depends on its melting *** initial color-change temperature(blue to red)is determined by the onset melting tem perature,and the temperature range in which reversible color recovery can be achieved by repeat heating-cooling treatment is determined by its melting *** to the proposed thermochromic mechanism of PDA,various new PDA materials with precise thermochromic temperatu res and reversible thermochromic temperature ra nges can be designed and synthesized through the appropriate introduction of benzene ring and groups that can form hydrogen bonding interactions into the molecular structure of linear diacetylene *** work provides a perspective to the precise molecular structure design and the property regulation of the reversible thermochromic PDA materials.

关键词： Polydiacetylene Thermochromism Hydrogen bonding Chemical modification

Optimization of the co-closing law of guide vanes and blades for bulb turbines based on CFD

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Journal of Hydrodynamics 2024年第2期36卷 363-377页

作者： Hui Liu Yun-fa Lin Yong-guang Cheng Song Xue mao-jia Tang Jian Zhang Jia-yi fan State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan430072China Dongfang Electric Machinery Co. Ltd.Deyang618000China

The load rejection transient process of bulb turbine units is critical to safety of hydropower stations,and determining appropriate closing laws of guide vanes(GVs)and runner blades(RBs)for this process is of *** this study,we proposed a procedure to optimize the co-closing law of GVs and RBs by using computational fluid dynamics(CFD),combined with the design of experiment(DOE)method,approximation model,and genetic optimization *** sensitivity of closing law parameters on the histories of head,speed,and thrust was analyzed,and a two-stage GVs’closing law associating with a linear RBs’closing law was *** results show that GVs dominate the transient characteristics by controlling the change of *** GVs’first-stage closing speed while shortening first-stage closing time can not only significantly reduce the maximum rotational speed but also suppress the water hammer pressure;slowing GVs’second-stage closing speed is conducive to controlling the maximum reverse axial *** directly affect the runner *** RBs’closing speed can further reduce the rotational speed and the maximum reverse axial *** safety margin of each control parameter,flow patterns,and pressure pulsations of a practical hydropower station were all improved after optimization,demonstrating the effectiveness of this method.

关键词： Bulb turbine load rejection transient process double regulation closing law optimization computational fluid dynamics(CFD)

The coupling control of biological precursors and environmental factors onβ-carotane enrichment in alkaline lacustrine source rocks:A case study from the Fengcheng formation in the western Junggar Basin,NW China

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Petroleum Science 2024年第2期21卷 836-854页

作者： mao-Guo Hou Ming Zha Hua Liu Hai-Lei Liu Jiang-Xiu Qu Ablimit Imin Xiu-Jian Ding Zhong-fa Jiang School of geosciences China University of PetroleumQingdaoShandong266580China Research Institute of Exploration and Development Xinjiang Petroleum Administration BureauKaramayXinjiang834000China

The organic-rich mudstones and dolostones of the Permian Fengcheng Formation(Fm.)are typically alkaline lacustrine source rocks,which are typified by impressively abundantβ-*** β-carotane has been well acknowledged as an effective indicator of biological sources or depositional ***,the specific biological sources of β-carotane and the coupling control of biological sources and environmental factors on the enrichment of β-carotane in the Fengcheng *** *** on a comprehensive investigation of the bulk,molecular geochemistry,and organic petrology of sedimentary rocks and the biochemistry of phytoplankton in modern alkaline lakes,we proposed a new understanding of the biological precursors of β-carotane and elucidated the enrichment mechanism of β-carotane in the Fengcheng *** results show that the biological precursors crucially control the enrichment of β-carotane in the Fengcheng *** haloalkaliphilic cyanobacteria are the primary biological sources of β-carotane,which is suggested by a good positive correlation between the 2-methylhopane index,7-+8-methyl heptadecanes/C_(max),C_(29%),and β-carotane/C_(max)in sedimentary rocks and the predominance of cyanobacteria with abundantβ-carotene in modern alkaline *** enrichment of β-carotane requires the reducing condition,and the paleoredox state that affects the enrichment of β-carotane appears to have a *** paleoclimate conditions do not considerably impact the enrichment of β-carotane,but they have some influence on the water's paleosalinity by affecting evaporation and *** it does not directly affect the enrichment of β-carotane in the Fengcheng Fm.,paleosalinity does have an impact on the cyanobacterial precursor supply and the preservation conditions.

关键词： β-carotane enrichment Cyanobacterial input Environmental impact Alkaline lacustrine source rocks The Fengcheng formation

Electronic structure of 4,4′-dipyridyidisuifide

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Electronic structure of 4,4′-dipyridyidisuifide

Differentiated self-assembly through orthogonal noncovalent interactions towards the synthesis of two-dimensional woven supramolecular polymers

中国化学会第五届全国结构化学学术会议

作者： Lin Du mao-fa ge Beijing National Laboratory for Molecular Sciences (BNLMS),Institute of Chemistry,Chinese Academy of Sciences,Beijing 100080.

＜正＞In recent years,coordination polymers with the ligand of 4,4′-dipyridyldisulfide（4DPDS） have been extensively developed[1].Because sulfur and amine spacers give the ligand a bent structure,the corresponding coordination polymers are structurally more complicated than those contain linear ***,both sulfur and amine moiety has the ability of coordination, which could also result in complicated structures of the *** electronic structure of

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来源： cnki会议评论

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Chinese Chemical Letters 2024年第5期35卷 179-182页

作者： Zhenzhu Wang Chenglong Liu Yunpeng ge Wencan Li Chenyang Zhang Bing Yang Shizhong mao Zeyuan Dong State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China Center for Supramolecular Chemical Biology Jilin UniversityChangchun 130012China

Molecular weaving is a powerful approach to make molecularly woven materials that have showed unprecedented characteristics and properties intrinsically distinct to those of non-woven *** here report a facile and efficient approach for the synthesis of 2D woven supramolecular polymers by differentiated self-assembly through orthogonal noncovalent ***,the difference in binding strength of two orthogonal noncovalent interactions can be used to control the process of molecular ***,single-layered 2D woven supramolecular polymers were synthesized and fully characterized by various *** study demonstrates a controllable method for molecular weaving,and will significantly hasten the development of molecularly woven materials.

关键词： Differentiated self-assembly Double-stranded helix Molecular weaving Supramolecular chemistry Two-dimensional polymer