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Acta Mathematica Sinica,English Series 2024年第6期40卷 1521-1532页

作者： peng cheng li Dong He PEI Xin ZHAO School of Mathematics and Statistics Northeast Normal UniversityChangchun 130024P.R.China Department of Mathematics Harbin Institute of TechnologyWeihai 264209P.R.China School of Mathematics and Statistics Qingdao UniversityQingdao 266071P.R.China

In this paper,we define the evolute and focal surface of a spacelike framed curve with lightlike components in Minkowski *** is a generalization of the previous results of regular spacelike curves,since singularities are allowed in the original spacelike curves studied by spacelike framed curves with lightlike ***,we show a new geometric invariant to characterise singularities of the focal ***,the classification theorem and recognition theorem for the singularities of the focal surface in generic are also given.

关键词： Evolutes focal surfaces spacelike framed curves singularities

Effect of ceramic work rolls on surface roughness of rolled SUS304 ultra-thin strips

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Journal of Iron and Steel Research(International) 2024年第7期31卷 1704-1718页

作者： peng-cheng li Tao Wang Chen-chen Zhao Qi liu Qing-xue Huang College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment of Ministry of Education Taiyuan University of TechnologyTaiyuan 030024ShanxiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment Taiyuan University of TechnologyTaiyuan 030024ShanxiChina

Surface morphology and roughness are important parameters of surface quality of cold-rolled ultra-thin strip *** order to study the effect of Si_(3)N_(4) ceramic work rolls on the surface roughness of SUS304 ultra-thin strip,ABAQUS finite element model calculation,3D laser profilometry,and other methods were adopted based on the physical characteristics of Si_(3)N_(4) ceramic roll and 9Cr2MoV steel roll,like anti-flattening performance and oil *** surface morphology and roughness of SUS304 ultra-thin strip rolled by different material work rolls under oil lubrication conditions were *** results showed that under the rolling force of 10 kN,the maximum flattening amount of Si_(3)N_(4) ceramic roll was reduced by 35.14%compared to that of 9Cr2MoV steel *** reduction rate of SUS304 ultra-thin strip rolled by ceramic roll was 34.19%,while that rolled by steel roll was only 22%;Si_(3)N_(4) ceramic roll can further increase the number of alternating convex peaks and concave valleys in the rolled thin strip,reduce the profile steepness,reduce surface roughness,and enhance the planarization effect of surface micro-convex bodies,with improving surface quality and surface ***,the mechanism of Si_(3)N_(4) ceramic roll significantly improving the surface roughness of rolled SUS304 ultra-thin strip was proposed.

关键词： Ceramic work roll-Steel roll SUS304 ultra-thin strip Reduction Surface roughness

Polymer-on-HOF: a new strategy for fabricating “armour-plated” HOFs to sequester radioactive anions

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Science China Chemistry 2024年第9期67卷 2958-2967页

作者： Hai-Ruo li Shitao Wu Xuezhuo Jing Zhengyi Di Kun liu Lu Wang cheng-peng li Zhong liu Miao Du College of Chemistry Tianjin Key Laboratory of Structure and Performance for Functional Molecules Tianjin Normal University Shanghai Key Laboratory of High-Resolution Electron Microscopy School of Physical Science and Technology Shanghai Tech University Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Provincial Key Laboratory of Resources and Chemistry of Salt Lakes Qinghai Institute of Salt Lakes Chinese Academy of Sciences College of Material and Chemical Engineering Institute of New Energy Science and Technology School of Future Hydrogen Energy Technology Zhengzhou University of Light Industry

The development of hydrogen-bonded organic frameworks（HOFs） faces significant constraints, primarily attributed to their fragile architectures and limited functionalization capabilities. To overcome these limitations, this work presents a new polymeron-HOF strategy by covalently tethering armor-like polymers onto the surface of HOFs. The application of this approach not only bolsters the stability of HOFs, but also facilitates the customization of their functional expansion in radionuclide sequestration. The optimized HOF-polymer materials display extraordinary ability in radionuclide sequestration, achieving uptake of I–(0.699 g g–1), IO3–(0.285 g g–1) and ReO4–(1.616 g g–1, setting a world record), fast adsorption kinetics（～100% removal within 45 s）, and exceptional regeneration capability（>30 cycles） under continuous flow conditions. These outstanding performances benefit from the internal porous channels and surface imidazolium polymer coatings of HOFs, as proved by density functional theory calculation and molecular dynamics simulations. This work paves the way for the rational design of HOF-based hybrid materials tailored to versatile applications.

关键词： hydrogen-bonded organic frameworks (HOFs) post-synthetic modification radionuclide sequestration

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Rapid progress of an iris metastasis from esophageal cancer:a case report and review of literature

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1557-1567页

作者： Meng Xie Xing-Hua Wang Jun-Jie Yang Zi-Xuan Su Jia-Hui Huang peng-cheng li Fa-Gang Jiang Department of Ophthalmology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina

This case report details a rare instance of rapid iris metastasis from esophageal cancer in a 59-year-old man.A literature review was conducted to explore recent advances in detecting,diagnosing,and treating intraocular metastatic *** emission tomographycomputed tomography played a crucial role in identifying primary sites and systemic *** treatment combined with systemic therapy effectively reduced tumor size,preserved useful vision,and improved the patient’s survival rate.A comparison was made of the characteristics of iris metastases from esophageal cancer and lung cancer,including age,gender,tumor characteristics,and *** challenges associated with diagnosis and treatment are discussed,highlighting the implications for clinical practice.

关键词： iris metastasis esophageal cancer positron emission tomography-computed tomography review

Prognostic significance of oligodendrocyte transcription factor 2 expression in glioma patients:A systematic review and metaanalys

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World Journal of Clinical Cases 2024年第25期12卷 5739-5748页

作者： peng-cheng li De-Bo Yun Ya-Xin Huang Qian-Yi Huang Department of Neurosurgery The Affiliated Nanchong Central Hospital of North Sichuan Medical CollegeNanchong 637000Sichuan ProvinceChina Department of Transfusion The Affiliated Nanchong Central Hospital of North Sichuan Medical CollegeNanchong 637000Sichuan ProvinceChina

BACKGROUND Gliomas are the most common primary central nervous system *** recent advances in the diagnosis and treatment of gliomas,patient prognosis remains ***,it is imperative to identify novel diagnostic biomarkers and therapeutic targets of glioma to effectively improve treatment *** To investigate the association between oligodendrocyte transcription factor 2(Olig2)expression and the outcomes of glioma *** The PubMed,Embase,Cochrane library,and China National Knowledge Infrastructure databases were searched for studies(published up to October 2023)that investigated the relationship between Olig2 expression and prognosis of glioma *** quality of the studies was assessed using the Newcastle Ottawa *** analyses were performed using Stata Version 12.0 *** A total of 1205 glioma patients from six studies were included in the *** Olig2 expression was associated with better outcomes in glioma patients[hazard ratio(HR):0.81;95%(confidence interval)CI:0.51-1.27;P=0.000].Furthermore,the results of subgroup meta-analysis showed that high expression of Olig2 was associated with poor overall survival in European patients(HR:1.34;95%CI:0.79-2.27)and better prognosis in Asian patients(HR:0.43;95%CI:0.22-0.84).The sensitivity analysis showed that no single study had a significant effect on pooled HR,and there was also no indication of publication bias according to the Egger’s and Begger’s P value test or funnel plot *** High Olig2 expression may have a positive impact on the prognosis of glioma patients,and should be investigated further as a prognostic biomarker and therapeutic target for glioma.

关键词： Glioma Oligodendrocyte transcription factor 2 Prognosis Biomarker Meta-analysis

Recent Progress in Covalent Organic Frameworks(COFs) for Electrocatalysis

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Chinese Journal of Structural Chemistry 2022年第11期41卷 84-99页

作者： Cha li Zining Qiu Hongming Sun Yijie Yang cheng-peng li College of Chemistry Tianjin Key Laboratory of Structure and Performance for Functional MoleculesTianjin Normal UniversityTianjin 300387China

Electrocatalysis provides various technologies for energy storage and conversion,which is an important part of realizing sustainable clean energy for the ***,as emerging porous crystalline polymers,possess high specific surface areas,tunable pore structures,high crystallinity and tailorable *** features endow COFs with abundant active sites and fast electron transport channels,making them potentially efficient *** recent years,COF-based electrocatalysts have been widely developed for hydrogen evolution reaction(HER),hydrogen oxidation reaction(HOR),oxygen evolution reaction(OER),oxygen reduction reaction(ORR),nitrogen reduction reaction(NRR)and carbon dioxide reduction reaction(CO_(2)RR).In this review,design strategies of COF-based electrocatalysts are briefly summarized,including applying COF as supports,introducing active metals in COF,constructing two-dimensional conductive COF,formation of COF-based hybrid and pyrolysis of COF to obtain carbon ***,the recent research progress in COF-derived catalysts for specific electrocatalytic reactions is introduced ***,the outlook and challenges of future applications of COFs in electrocatalysis are highlighted.

关键词： covalent organic frameworks electrocatalyst catalytic performance catalytic kinetics energy conversion

Synthesis of Diverse 1,4-(Azaindole)[60] fullerenes via Transition- Metal Free Three-Component Coupling Reaction of Azaindoles, C_(60), and Bromoalkanes/Triphenylamines

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Chinese Journal of Chemistry 2023年第22期41卷 2975-2980页

作者： Xinmin Huang Zi-Zheng liu Jia-Qi cheng cheng-Yu Cao peng-cheng li Jun Xuan Fei li Department of Chemistry Anhui UniversityKey Laboratory of Structure and Functional Regulation of Hybrid Materials(Anhui University)Ministry of EducationAnhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials and Key Laboratory of Functional Inorganic Materials of Anhui ProvinceHefeiAnhui 230601China Department of Chemistry University of Science and Technology of ChinaHefeiAnhui 230026China

A transition-metal free three-component coupling reaction of azaindoles,C_(60),and bromoalkanes/triphenylamines has been developed to provide an efficient access to diverse azaindole functionalized 1,4-C_(60) *** prot... 详细信息

关键词： Azaindoles Fullerenes 1,4-(Azaindole)fullerenes Transition-metal free Cross-coupling

Effects of sequential decay on collective flows and nuclear stopping power in heavy-ion collisions at intermediate energies

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Nuclear Science and Techniques 2023年第4期34卷 175-184页

作者： Kui Xiao peng-cheng li Yong-Jia Wang Fu-Hu liu Qing-Feng li State Key Laboratory of Quantum Optics and Quantum Optics Devices and Collaborative Innovation Center of Extreme Optics Institute of Theoretical PhysicsShanxi UniversityTaiyuan 030006China School of Science Huzhou UniversityHuzhou 313000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Institut für Theoretische Physik Goethe Universität FrankfurtFrankfurt am Main 60438Germany Institute of Modern Physics Chinese Academy of ScienceLanzhou 730000China

In this study, the rapidity distribution, collective flows, and nuclear stopping power in ^(197)Au+^(197)Au collisions at intermediate energies were investigated using the ultrarelativistic quantum molecular dynamics(UrQMD) model with GEMINI++ code. The UrQMD model was adopted to simulate the dynamic evolution of heavy-ion collisions, whereas the GEMINI++ code was used to simulate the decay of primary fragments produced by UrQMD. The calculated results were compared with the INDRA and FOPI experimental data. It was found that the rapidity distribution, collective flows, and nuclear stopping power were affected to a certain extent by the decay of primary fragments, especially at lower beam energies. Furthermore, the experimental data of the collective flows and nuclear stopping power at the investigated beam energies were better reproduced when the sequential decay effect was included.

关键词： Heavy-ion collisions Sequential decay effect Collective flow Nuclear stopping power

Recent Advances in C_(2) Gases Separation and Purification by Metal-Organic Frameworks

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Chinese Journal of Structural Chemistry 2022年第11期41卷 31-44页

作者： Zhengyi Di Xinjing Zheng Yu Qi Heng Yuan cheng-peng li College of Chemistry Tianjin Key Laboratory of Structure and Performance for Functional MoleculesTianjin Normal UniversityTianjin 300387China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002.China

Separation of C_(2) gases(C_(2)H_(2)/C_(2)H_(4),C_(2)H_(6)/C_(2)H_(4) and C_(2)H_(2)/CO_(2))mixtures is one of the most important and energy-demanding processes in chemical *** separation methods(fine distillation separation and selective catalytic hydrogenation separation)have the shortages of high energy consumption and inefficient use of resources,affecting the achievement of peak carbon dioxide emissions and carbon neutrality *** based on adsorption is considered as one of the best ways to achieve low-energy ***,it is of great importance to synthesize materials that enable the effective separation and purification of C_(2) gases under mild *** an emerging class of porous materials,metal-organic frameworks(MOFs)show great promise in the field of gas separation and purification due to their ultra-high specific surface area,easily modifiable pore surfaces,structural designability and ***,we summarize recent research advances by use of MOFs sorbents for the separation and purification of C_(2) gases,including C_(2)H_(2)/C_(2)H_(4),C_(2)H_(6)/C_(2)H_(4) and C_(2)H_(2)/CO_(2).Relationship between structures and separation mechanism is also ***,challenges and possible research directions related to the further exploration are also discussed.

关键词： MOFs adsorption and separation C_(2)gas design and synthesis pore size

Unsupervised construction of health indicator for rotating machinery via multi-criterion feature selection and attentive variational autoencoder

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Science China(Technological Sciences) 2024年第5期67卷 1524-1537页

作者： li XinYu cheng ChangMing peng ZhiKe State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai200240China School of Mechanical Engineering Ningxia UniversityYinchuan750021China

Health indicator(HI)construction is a crucial task in degradation evaluation and facilitates the prognostic and health management(PHM)of rotating *** interference from artificial labeling,the HI construction approaches in an unsupervised manner have attracted substantial ***,current unsupervised methods generally struggle with two problems:(1)ignorance of both redundancy between features and global variability of features during the feature selection process;(2)inadequate utilization of information from different sampling *** tackle these problems,this work develops a novel unsupervised approach for HI construction that integrates multi-criterion feature selection and the Attentive Variational Autoencoder(Attentive VAE).Explicitly,a multi-criterion feature selection(Mc FS)algorithm together with an elaborately designed metric is proposed to determine a superior feature subset,considering the relevance,the redundancy,and the global variability of features ***,for the adequate utilization of the information from distinct sampling moments,a deep learning model named Attentive VAE is *** Attentive VAE is solely fed with the selected features in the health state for model training and the HI is derived through the reconstruction error to reveal the degradation degree of *** case studies based on genuine experimental datasets are involved to quantitatively evaluate the superiority of the developed approach,demonstrating its superiority over other unsupervised methods for characterizing degradation *** effectiveness of both the Mc FS algorithm and the Attentive VAE is verified by ablation experiments,respectively.

关键词： health indicator(HI) unsupervised learning multi-criterion feature selection global variability attention mechanism