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Ligand-Enabled Ni-Catalyzed Enantioselective Hydroarylation of Styrenes and 1,3-Dienes with Arylboronic Acids

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CCS Chemistry 2019年第4期1卷 328-334页

作者： Xin-Yang lv chao fan Li-Jun Xiao Jian-Hua Xie Qi-Lin Zhou State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071China

We report an enantioselective hydroarylation reaction of styrenes and 1,3-dienes with arylboronic acids catalyzed by nickel complexes bearing chiral spiro amino phosphine *** reaction serves as an efficient,straightf orward,and mild method for the preparation of enantio enriched 1,1-diarylalkanes,which are important building blocks for the synthesis of many biologically active *** redox neutral reaction uses only catalytic amounts of the reagents and is,therefore,atom economical and environmentally benign.

关键词： nickel catalyst enantioselective hydroarylation alkene organoboron chiral spiro aminophosphine

Highly Sensitive Ammonia Gas Sensors at Room Temperature Based on the Catalytic Mechanism of N,C Coordinated Ni Single-Atom Active Center

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Nano-Micro Letters 2024年第12期16卷 515-531页

作者： Wenjing Quan Jia Shi Min Zeng Wen lv Xiyu Chen chao fan Yongwei Zhang Zhou Liu Xiaolu Huang Jianhua Yang Nantao Hu Tao Wang Zhi Yang National Key Laboratory of Advanced Micro and Nano Manufacture Technology Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Department of Micro/Nano Electronics School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Shanghai Key Laboratory of Intelligent Sensing and Detection Technology School of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237People’s Republic of China

Significant challenges are posed by the limitations of gas sensing mechanisms for trace-level detection of ammonia(NH3).In this study,we propose to exploit single-atom catalytic activation and targeted adsorption properties to achieve highly sensitive and selective NH3 gas ***,Ni singleatom active sites based on N,C coordination(Ni-N-C)were interfacially confined on the surface of two-dimensional(2D)MXene nanosheets(Ni-N-C/Ti_(3)C_(2)Tx),and a fully flexible gas sensor(MNPE-Ni-N-C/Ti_(3)C_(2)Tx)was *** sensor demonstrates a remarkable response value to 5 ppm NH3(27.3%),excellent selectivity for NH3,and a low theoretical detection limit of 12.1 *** analysis by density functional calculation reveals that the Ni single-atom center with N,C coordination exhibits specific targeted adsorption properties for ***,its catalytic activation effect effectively reduces the Gibbs free energy of the sensing elemental reaction,while its electronic structure promotes the spill-over effect of reactive oxygen species at the gas-solid *** sensor has a dual-channel sensing mechanism of both chemical and electronic sensitization,which facilitates efficient electron transfer to the 2D MXene conductive network,resulting in the formation of the NH3 gas molecule sensing ***,the passivation of MXene edge defects by a conjugated hydrogen bond network enhances the long-term stability of MXene-based electrodes under high humidity *** work achieves highly sensitive room-temperature NH3 gas detection based on the catalytic mechanism of Ni single-atom active center with N,C coordination,which provides a novel gas sensing mechanism for room-temperature trace gas detection research.

关键词： Gas sensor Single atom Catalytic activation Targeted adsorption End-sealing passivation

Visualization study on atomization characteristics and heat transfer performance of R1336mzz flash spray cooling

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Science China(Technological Sciences) 2021年第10期64卷 2099-2109页

作者： ZHANG ZhiWei HU DingHua LI Qiang LIU chao ZHOU fan MIIT Key Laboratory of Thermal Control of Electronic Equipment Nanjing University of Science and TechnologyNanjing 210094China

Visualization experiments are carried out to investigate the atomization characteristics of R1336mzz flash spray *** influences of superheat,spray distance,and nozzle orifice diameter on spray cooling performance are analyzed *** the superheat increases,finer droplets and thinner liquid film are observed;this is helpful to improve the two-phase heat transfer *** atomization angle under high superheat is also observed for flash spray cooling,and it benefits for reducing the spray *** can be found that when the inlet superheat is 19.8℃ and the spray distance is 6 mm,the critical heat flux(CHF)reaches 251 W/cm^(2) and the maximum heat transfer coefficient(HTC)reaches 37.4 kW/(m^(2)℃),which are 55%and 11.6%higher than those when the inlet subcooling is 6.9℃ and the spray distance is 12 mm,*** flash spray reduces the spray distance,which benefits for designing compact spray cooling *** addition,the nozzle orifice diameter has great influence on the cooling performance of flash spray,and the choice of the nozzle depends on the *** study provides a physical insight into the heat transfer enhancement in flash spray cooling.

关键词： flash spray cooling superheat spray distance nozzle diameter R1336mzz critical heat flux

PPy-Encapsulated Na_(2)Li_(2)Ti_(6)O_(14) Composites as High-Performance Anodes for Li-Ion Battery

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Acta Metallurgica Sinica(English Letters) 2022年第11期35卷 1873-1881页

作者： fan-fan Wang Nan Zhang Ze-Chen lv Yan-Rong Zhu Jun-Hong Zhang Ting-Feng Yi School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Shandong Provincial Key Laboratory of Chemical Energy Storageand Novel Cell Technology Collegeof Chemistry and Chemical EngineeringLiaocheng UniversityLiaocheng 252059China School of Resources and Materials Northeastern University atQinhuangdaoQinhuangdao 066004China KeyLaboratory of Dielectric and Electrolyte Functional Material Hebei Province Qinhuangdao 066004China

Na_(2)Li_(2)Ti_(6)O_(14) as a reliable anode material is becoming a hopeful candidate for Li-ion ***,the pristine Na_(2)Li_(2)Ti_(6)O_(14) usually suffer from bad rate performance and poor cycling stability under high current due to limited diffusion kinetics and poor electrical ***,the PPy-coated Na_(2)Li_(2)Ti_(6)O_(14) composites are successfully obtained via the solid-state method and followed by chemical oxidation process in the first *** results of tests prove that the Na_(2)Li_(2)Ti_(6)O_(14)@PPy composites have better electrochemical performance than the bare Na_(2)Li_(2)Ti_(6)O_(14) because of the excellent electrical conductivity and the special macromolecular architecture of *** particular,the Na_(2) Li_(2) Ti_(6) O_(14) @PPy(4 wt%)exhibits excellent charge capacities of about 223.2,218.0,200.8,184.3 and 172.6 mAh g^(-1) at 50,100,200,300 and500 mA g^(-1),respectively,revealing the best rate capability of all electrode *** Na_(2)Li_(2)Ti_(6)O_(14)@PPy(4 wt%)not only has the highest charge capacity under 0.5 mA g^(-1),but also has the highest capacity retention of 85.12%among all samples after 100 ***,the PPy coating is known as a promising way to improve the electrochemical property of Na_(2)Li_(2)Ti_(6)O_(14).The PPy-coated Na_(2)Li_(2)Ti_(6)O_(14) demonstrates the great prospect as promising negative materials for Li-ion batteries.

关键词： Li-ion battery Anode material Na_(2)Li_(2)Ti_(6)O_(14) PPy coating Electrochemical property

Discovery of Kaempferol,a Novel ADAM10 Inhibitor,as a Potential Treatment for Staphylococcus aureus Infection

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Engineering 2023年第9期28卷 206-221页

作者： Tingting Wang Jianfeng Wang Xiangzhu Xu fan Jiang Hongfa lv Qinghui Qi Can Zhang Qianghua lv Xuming Deng Department of Respiratory Medicine Center for Pathogen Biology and Infectious Diseases&Key Laboratory of Organ Regeneration and Transplantation of the Ministry of EducationState Key Laboratory for Zoonotic DiseasesThe First Hospital of Jilin UniversityChangchun 130021China State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases&Key Laboratory of Zoonosis Research Ministry of EducationInstitute of ZoonosisCollege of Veterinary MedicineJilin UniversityChangchun 130062China Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education School of Life SciencesJilin UniversityChangchun 130012China Key Laboratory of Livestock and Poultry Multi-omics of MARA&Shandong Key Laboratory of Animal Disease Control and Breeding Institute of Animal Science and Veterinary MedicineShandong Academy of Agricultural SciencesJinan 250100China

Host-directed therapy(HDT)is an emerging novel approach for treating multidrug-resistant Staphylococcus aureus(***)*** as the indispensable specific cellular receptor for a-toxin(Hla),a-disintegrin and metalloproteinase 10(ADAM10)is exploited to accelerate *** infection through diverse *** extraordinary contribution of ADAM10 to *** pathogenesis renders it an attractive HDT target for combating *** *** study is the first to demonstrate the indispensable role of ADAM10 in ***-induced necroptosis,and it enhances our knowledge of the role of ADAM10 in *** *** a fluorogenic substrate assay,we further identified kaempferol as a potent ADAM10 inhibitor that effectively protected mice from *** infection by suppressing Hla-mediated barrier disruption and ***,our work presents a novel hostdirected therapeutic strategy for using the promising candidate kaempferol to treat *** infection and other diseases relevant to the disordered upregulation of ADAM10.

关键词： Host-directed therapy Kaempferol ADAM10 inhibitor Staphylococcus aureus infection Barrier disruption Necroptosis

Three‑dimensional Modeling and Simulation of Muscle Tissue Puncture Process

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Chinese Journal of Mechanical Engineering 2022年第3期35卷 174-186页

作者： Zongkai lv Qinghua Song fan Gao Zhanqiang Liu Yi Wan Yonghang Jiang School of Mechanical Engineering Shandong UniversityJinan 250061China Key Laboratory of High Efficiency and Clean Mechanical Manufacture Ministry of EducationShandong UniversityJinan 250061China National Demonstration Center for Experimental Mechanical Engineering Education Shandong UniversityJinan 250061China Centre for Precision Manufacturing Department of DesignManufacturing and Engineering ManagementUniversity of StrathclydeGlasgow G40NTUK

Needle biopsy is an essential part of modern clinical *** puncture accuracy and sampling success rate of puncture surgery can be effectively improved through virtual *** are few three-dimensional puncture(3D)models,which have little significance for surgical guidance under complicated conditions and restrict the development of virtual *** this paper,a 3D simulation of the muscle tissue puncture process is ***,the mechanical properties of muscle tissue are *** Mooney-Rivlin(M-R)model is selected by considering the fitting accuracy and calculation ***,an accurate 3D dynamic puncture model is *** failure criterion is used to define the breaking characteristics of the muscle,and the bilinear cohesion model defines the breaking *** with different puncture speeds are carried out through the built in vitro puncture *** experimental results are compared with the simulation *** experimental and simulated reaction force curves are highly consistent,which verifies the accuracy of the ***,the model under different parameters is *** simulation results of varying puncture depths and puncture speeds are *** 3D puncture model can provide more accurate model support for virtual surgery and help improve the success rate of puncture surgery.

关键词： Puncture biopsy Muscle soft tissue 3D Puncture Simulation

Global Complexity Bound of the Inexact Levenberg–Marquardt Method

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Journal of the Operations Research Society of China 2018年第3期6卷 417-428页

作者： Jian-chao Huang Jin-Yan fan School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240China School of Mathematical Sciences MOE-LSCShanghai Jiao Tong UniversityShanghai 200240China

In this paper,we investigate the global complexity bound for the inexact Levenberg–Marquardt method,where the Jacobian may be perturbed and the solution is possibly not *** reasonable assumptions,we show that the global complexity bound is O(ε^(−2)),which is the same as the exact *** also show that it can be reduced to O(lgε^(−1))under some regularity assumption.

关键词： Global complexity bound Inexact Levenberg–Marquardt method Nonlinear equations

Probabilistic Top-k Query:Model and Application on Web Traffic Analysis

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China Communications 2016年第6期13卷 123-137页

作者： Xiaolin Gui Jun Liu Qiujian lv chao Dong Zhenming Lei Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and TelecommunicationsBeijing100876China Agricultural Bank of China Beijing 100161 China

Top-k ranking of websites according to traffic volume is important for Internet Service Providers(ISPs) to understand network status and optimize network resources. However, the ranking result always has a big deviation with actual rank for the existence of unknown web traffic, which cannot be identified accurately under current techniques. In this paper, we introduce a novel method to approximate the actual rank. This method associates unknown web traffic with websites according to statistical probabilities. Then, we construct a probabilistic top-k query model to rank websites. We conduct several experiments by using real HTTP traffic traces collected from a commercial ISP covering an entire city in northern China. Experimental results show that the proposed techniques can reduce the deviation existing between the ground truth and the ranking results vastly. In addition, we find that the websites providing video service have higher ratio of unknown IP as well as higher ratio of unknown traffic than the websites providing text web page service. Specifically, we find that the top-3 video websites have more than 90% of unknown web traffic. All these findings are helpful for ISPs understanding network status and deploying Content Distributed Network(CDN).

关键词： top-k query traffic model temporal bipartite graph uncertain data unknown traffic

Trend and Factors of Population Fertility Changes From the Perspective of Economics and Education——China,1949-2020

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China CDC weekly 2021年第28期3卷 599-603,I0002页

作者： Yiran Wang Huiyun fan chao Guo Institute of Population Research Peking UniversityBeijingChina APEC Health Science Academy(HeSAY) Peking UniversityBeijingChina

Summary What is already known on this topic?Diverse social factors such as economic development,policy,culture,and special historical events could affect population fertility *** present,the influence of social factors on fertility is still *** the diversification of population characteristics,the crossgroup robustness of the classical theories and research conclusions are broken.

关键词： Population fertility policy