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Photoredox-catalyzed C-glycosylation of peptides with glycosyl bromides

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Chinese Chemical Letters 2024年第6期35卷 263-267页

作者： Chen Li Ziyuan Zhao Shouyun yu State Key Laboratory of Analytical Chemistry for Life Science Jiangsu Key Laboratory of Advanced Organic MaterialsChemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Glycosyl radicals,produced under mild photoredox conditions,show unique utility in the preparation of C-linked *** herein report the construction of C-glycosidic bonds on α,β-dehydroalanine(DHA)of peptides with easily available glycosyl bromides as glycosyl radical precursors under highly anomeric control,leading to C-glycosylation modifications of *** method not only has outstanding functional group compatibility,but also is feasible in near-physiological conditions(pH~7 and temperature T≤37℃ in aqueous media).

关键词： Glycosylation C-Glycosides Glycopeptides Dehydroalanine Photoredox catalysis

User Purchase Intention Prediction Based on Improved Deep Forest

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 661-677页

作者： Yifan Zhang Qiancheng yu Lisi Zhang School of Computer Science and Engineering North Minzu UniversityYinchuan750030China Laboratory of Graphics and Images of the State Ethnic Affairs Commission North Minzu UniversityYinchuan750030China

Widely used deep neural networks currently face limitations in achieving optimal performance for purchase intention prediction due to constraints on data volume and hyperparameter *** address this issue,based on the deep forest algorithm and further integrating evolutionary ensemble learning methods,this paper proposes a novel Deep Adaptive Evolutionary Ensemble(DAEE)*** model introduces model diversity into the cascade layer,allowing it to adaptively adjust its structure to accommodate complex and evolving purchasing behavior ***,this paper optimizes the methods of obtaining feature vectors,enhancement vectors,and prediction results within the deep forest algorithm to enhance the model’s predictive *** demonstrate that the improved deep forest model not only possesses higher robustness but also shows an increase of 5.02%in AUC value compared to the baseline ***,its training runtime speed is 6 times faster than that of deep models,and compared to other improved models,its accuracy has been enhanced by 0.9%.

关键词： Purchase prediction deep forest differential evolution algorithm evolutionary ensemble learning model selection

Probing the electric double layer structure at nitrogen-doped graphite electrodes by constant-potential molecular dynamics simulations

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Journal of Energy Chemistry 2024年第6期93卷 299-305,I0008页

作者： Legeng yu Nan Yao yu-Chen Gao Zhong-Heng Fu Bo Jiang Ruiping Li Cheng Tang Xiang Chen Tsinghua Center for Green Chemical Engineering Electrification(CCEE) Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China National Materials Corrosion and Protection Data Center University of Science and Technology BeijingBeijing 100083China Ordos Carbon Neutral Research and Application Co. Ltd.Ordos 017010Inner Mongoli1China Institute for Carbon Neutrality Tsinghua UniversityBeijing 100084China Center for Next-Generation Energy Materials and School of Chemical Engineering Sungkyunkwan University2066 Seobu-roJangan-guSuwon-siGyeonggi-do 16419Republic of Korea

Electric double layer(EDL)is a critical topic in electrochemistry and largely determines the working performance of lithium ***,atomic insights into the EDL structures on heteroatom-modified graphite anodes and EDL evolution with electrode potential are very ***,a constant-potential molecular dynamics(CPMD)method is proposed to probe the EDL structure under working conditions,taking N-doped graphite electrodes and carbonate electrolytes as an *** interface model was developed,incorporating the electrode potential and atom *** a result,an insightful atomic scenario for the EDL structure under varied electrode potentials has been established,which unveils the important role of doping sites in regulating both the EDL structures and the following electrochemical reactions at the atomic ***,the negatively charged N atoms repel the anions and adsorb Li~+at high and low potentials,*** preferential adsorption suggests that Ndoped graphite can promote Li~+desolvation and regulate the location of Li~+*** CPMD method not only unveils the mysterious function of N-doping from the viewpoint of EDL at the atomic level but also applies to probe the interfacial structure on other complicated electrodes.

关键词： Lithium batteries Graphite N-doping Electric double layer Molecular dynamics Constant potential method Electrode potential

Mean field game of optimal relative investment with jump risk

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Science China Mathematics 2024年第5期67卷 1159-1188页

作者： Lijun Bo Shihua Wang Xiang yu School of Mathematics and Statistics Xidian UniversityXi'an 710126China School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026China Department of Applied Mathematics The Hong Kong Polytechnic UniversityHong KongChina

In this paper,we study the n-player game and the mean field game under the constant relative risk aversion relative performance on terminal wealth,in which the interaction occurs by peer *** the model with n agents,the price dynamics of underlying risky assets depend on a common noise and contagious jump risk modeled by a multi-dimensional nonlinear Hawkes *** a continuum of agents,we formulate the mean field game problem and characterize a deterministic mean field equilibrium in an analytical form under some conditions,allowing us to investigate some impacts of model parameters in the limiting model and discuss some financial ***,based on the mean field equilibrium,we construct an approximate Nash equilibrium for the n-player game when n is sufficiently *** explicit order of the approximation error is also derived.

关键词： relative performance contagious jump risk mean field game with jumps mean field equilibrium approximate Nash equilibrium

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Establishment and validation of an adherence prediction system for lifestyle interventions in non-alcoholic fatty liver disease

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World Journal of Gastroenterology 2024年第10期30卷 1393-1404页

作者： Ming-Hui Zeng Qi-yu Shi Liang Xu yu-Qiang Mi Clinical School of the Second People’s Hospital Tianjin Medical UniversityTianjin 300192China Department of Gastroenterology Cangzhou People’s HospitalCangzhou 061000Hebei ProvinceChina Department of Hepatology Tianjin Second People’s HospitalTianjin 300192China Tianjin Research Institute of Liver Diseases Tianjin 300192China

BACKGROUND Non-alcoholic fatty liver disease(NAFLD)is the most common liver disease worldwide,affecting about 1/4th of the global population and causing a huge global economic *** date,no drugs have been approved for the treatment of NAFLD,making the correction of unhealthy lifestyles the principle method of *** patients with poor adherence to lifestyle correction and attempting to improve their adherence are therefore very *** To develop and validate a scale that can rapidly assess the adherence of patients with NAFLD to lifestyle *** The Exercise and Diet Adherence Scale(EDAS)was designed based on com-pilation using the Delphi method,and its reliability was subsequently *** and laboratory indicators were measured,and patients completed the EDAS questionnaire at baseline and after 6 *** efficacy of the EDAS was evaluated in the initial ***,the efficacy of the EDAS was internally verified in a validation *** The EDAS consisted of 33 items in six dimensions,with a total of 165 *** EDAS score correlated significantly with daily number of exercise and daily reduction in calorie intake(P500 kacl/d),(sensitivity/specificity was 100.0%/75.8%),while patients score below 97 could nearly rule out the possibility of daily exercise(sensitivity/specificity was 89.5%/44.4%).Total EDAS scores≥116,97-115,and<97 points were indicative of good,average,and poor adherence,respectively,to diet and exercise *** The EDAS can reliably assess the adherence of patients with NAFLD to lifestyle interventions and have clinical application in this population.

关键词： Fatty liver Lifestyle intervention Behavioral change Patient adherence Compliance

Analysis of mechanical strengths of extreme line casing joint considering geometric, material, and contact nonlinearities

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Petroleum Science 2024年第3期21卷 1992-2004页

作者： Ji-yun Zhang Chi Peng Jian-Hong Fu Quan Cao yu Su Jian-yun Pang Zi-Qiang yu Petroleum Engineering School Southwest Petroleum UniversityChengdu610500SichuanChina Engineering Technology Research Institute of CNPC Southwest Oil and Gas Field Company Chengdu610017SichuanChina

To address the challenges associated with difficult casing running,limited annular space,and poor cementing quality in the completion of ultra-deep wells,the extreme line casing offers an effective solution over conventional ***,due to its smaller size,the joint strength of extreme line casing is reduced,which may cause failure when running in the *** address this issue,this study focuses on the CST-ZTΦ139.7 mm×7.72 mm extreme line casing and employs the elastic-plastic mechanics to establish a comprehensive analysis of the casing joint,taking into account the influence of geometric and material nonlinearities.A finite element model is developed to analyze the forces and deformations of the extreme line casing joint under axial tension and external collapse *** model investigates the stress distribution of each thread tooth subjected to various tensile forces and external ***,the tensile strength and crushing strength of the extreme line casing joint are determined through both analytical and experimental *** findings reveal that,under axial tensile load,the bearing surface of each thread tooth experiences uneven stress,with relatively high equivalent stress at the root of each thread *** end thread teeth are valuable spots for *** is observed that the critical fracture axial load of thread decreases linearly with the increase of thread tooth *** external pressure,the circumferential stress is highest at the small end of the external thread,leading to yield *** tensile strength of the joint obtained from the finite element model exhibits a relative error of less than 7%compared to the analytical and experimental values,proving the reliability of the finite element *** tensile strength of the joint is 3091.9 k ***,in terms of anti-collapse capability,the joints demonstrate higher resistance to collapse compared to the casing body,which is consistent with the test resul

关键词： Extreme line casing Elastic-plastic mechanics Finite element analysis Tensile strength Collapse strength

Free amino group-directed C(sp^(2))-H arylation ofα-amino-β-aryl esters by palladium catalysis

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Chinese Chemical Letters 2024年第2期35卷 358-360页

作者： yue Gao yu Du Weiping Su State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China University of Chinese Academy of Sciences Beijing 100049China

Native amino-directed palladium-catalyzed C(sp^(3))-H activation/functionalization has been developed for modification ofα-amino acids and *** a palladium(Ⅱ)-catalyzed C(sp^(2))-H arylation ofα-amino-β-aryl esters has been disclosed,using the native amino as the directing group.A variety of chiralα-amino-β-aryl esters can be functionalized to give the corresponding ortho-substituted mono-and di-arylated products.

关键词： Native amino-directed Palladium catalyst C(sp^(2))-H arylation α-Amino-β-aryl ester Chiralα-amino acid

Selective synthesis and physical properties of a bismacrocycle:Cycloparaphenylene-pillar[5]arene

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Chinese Chemical Letters 2024年第3期35卷 273-276页

作者： yu Zhou Guilin Zhuang Pingwu Du Key Laboratory of Precision and Intelligent Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleCAS Key Laboratory of Materials for Energy ConversionDepartment of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China College of Chemical Engineering Zhejiang University of TechnologyHangzhou 310032China

Macrocyclic materials have attracted much attention due to their particular chemical and physical *** we report the precise synthesis and characterization of a new bismacrocycle structure base on cycloparaphenylene(CPP)and pillar[5]arene,named cycloparaphenylene-pillar[5]arenes(CPPn[5]).The bismacrocycle was fully characterized by NMR and *** photophysical properties of CPPn[5]were investigated by UV–vis,and the maximum absorption peak was located at 331 nm,which was consistent with density functional theory(DFT)*** fluorescence spectrum was further studied and the emission peak was maximized at 458 *** computational results indicate the strain energy of CPPn[5]is 27.80 kcal/mol and the HOMO-LUMO gap is 3.39 eV Notably,CPPn[5]showed interesting supramolecular properties.

关键词： Pillararene Cycloparaphenylene Bismacrocycles Supramolecular chemistry

Robust tantalum tuned perovskite oxygen electrode for reversible protonic ceramic electrochemical cells

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Rare Metals 2024年第7期43卷 3055-3065页

作者： yu-Shi Feng yu Shen Fang Wang Chuan Tian Qin-Yi Hu Qian Duan Jing-Wei Li Di Bao School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China Zhongshan Institute of Changchun University of Science and Technology Zhongshan528437China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of SciencesChangchun 130022China Key Laboratory of Preparation and Applications of Environmental Friendly Materials Ministry of EducationJilin Normal UniversityChangchun 130103China

Perovskite oxides with diverse composition and structure have exhibited grand advances in boosting the oxygen reduction and evolution reaction(ORR/OER),which are essential for the reversible protonic ceramic electrochemical cell(R-PCEC)toward the sustainable hydrogen production and ***,enhancement of their activity and stability remains ***,we develop the Ta-regulated BaCo_(0.7)Fe_(0.3)O_(3-δ)perovskite oxygen electrode(Ba(Co_(0.7)Fe_(0.3))_(1-x)Ta_xO_(3-δ))with abundant oxygen defects and achieve the simultaneous enhancement in the electrocatalytic activity and stability toward ORR and ***-fabricated R-PCEC with(Ba(Co_(0.7)Fe_(0.3))_(0.9)Ta_(0.1)O_(3-δ))(BCFT10)oxygen electrode performs high power density of 1.47 W·cm^(-2)at 650℃in fuel cell mode,and the current density is up to-2.11 A·cm^(-2)at 1.4 V at 650℃in electrolysis mode,as well as the good stability in both the fuel cell and electrolysis ***,the cell also demonstrates a stable cycling operation between fuel cell and electrolysis mode,suggesting a great potential of BCFT10 as oxygen electrode material for R-PCECs.

关键词： Reversible protonic ceramic electrochemical cells Perovskite oxide Oxygen electrode Ta element doping Oxygen defects