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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

Nano-effect enhanced cooperative luminescence of Yb^(3+) clusters in bulk materials

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Journal of Rare Earths 2024年第3期42卷 473-478,I0002页

作者： Daguang Li Jiahao Cui Yanhui Dong Hao Cui Dan Zhao weiping Qin state Key Laboratory on Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun130012China

In order to improve the multi-ion cooperative transition, we proposed and exploited a novel nanoscale effect, namely the nanoshell effect in bulk materials. Based on the effect, an optimal material structure was designed by coating the surfaces of Ca F_(2):Yb^(3+)micron size particles with ZrO_(2). An about 2 times higher intensity of cooperative luminescence is observed upon laser excitation at 980 nm. Dynamical analysis exhibits that the novel effect plays a key role in improving the performance of cooperative transitions. Our results also suggest that the nanoshell effect in bulk materials is likely to be significant in some special cases, which have not been reported yet in the literature.

关键词： Yb^(3+)cluster ZrO_(2) Nanoshell Enhancement Cooperative luminescence Rare earths

Joint Transmit and Reflective Beamforming Design for Active IRS-Aided SWIPT Systems

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Chinese Journal of Electronics 2024年第2期33卷 536-548页

作者： weiping SHI Qingqing WU Di WU Feng SHU Jiangzhou WANG School of Electronic and Optical Engineering Nanjing University of Science and Technology Department of Electronic Engineering Shanghai Jiao Tong University School of Information and Communication Engineering Hainan University Department of Automation Shanghai Jiao Tong University School of Engineering University of Kent

To further improve the performance of passive intelligent reflecting surface(IRS)-assisted communication systems and mitigate the serious path loss due to “double-fading ” of IRS-assisted links, an active IRS-aided simultaneous wireless information and power transfer(SWIPT) system is investigated. This paper jointly optimizes the transmit beamforming at the base station(BS) and the phase shifts at the active IRS in order to maximize the power collected by the energy harvesting receiver under both perfect and imperfect channel state information(CSI)states, subject to the signal-to-interference-noise ratio constraint of the information decoding receiver, and the power constraints of the BS/IRS. Under perfect CSI, the alternating optimization algorithm is utilized for obtaining the transmit beamforming at the BS and the phase shifts at the active IRS. For each subproblem, we first transform nonconvex objective function and constraints into convex ones by performing a first-order Taylor expansion. Then, each subproblem is solved by using the interior point method. Given that obtaining perfect CSI is impractical, two robust beamforming designs are proposed for imperfect CSI case. Under the bounded CSI error model, we first transform the non-convex optimization problem into two semidefinite programming subproblems, and then solve each subproblem based on S-procedure and sequential rank-one constraint relaxation(SROCR) techniques. Under the stochastic CSI error model, the alternating optimization method is applied in an iterative manner based on Bernstein-type inequality and SROCR technique. Simulation results show that both robust and non-robust schemes for active IRS-assisted SWIPT systems can achieve extremely superior performance over conventional passive IRS-assisted systems under the same overall power budget.

关键词： Wireless communication Semidefinite programming Array signal processing Simulation Stochastic processes Transforms Receivers

A review of ^(17)O isotopic labeling techniques for solid-state NMR structural studies of metal oxides in lithium-ion batteries

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Magnetic Resonance Letters 2024年第2期4卷 46-53页

作者： Xiaoli Xia Lei Zhu weiping Tang Luming Peng Junchao Chen School of Chemistry and Chemical Engineering Shanghai Jiao Tong University800 Dongchuan RoadShanghai200240China Key Laboratory of Mesoscopic Chemistry of Ministry of Education and Collaborative Innovation Center of Chemistry for Life Sciences School of Chemistry and Chemical EngineeringNanjing University163 Xianlin RoadNanjing210023China state Key Laboratory of Space Power-Sources Technology Shanghai Institute of Space Power-SourcesShanghai200245China

Recent advances in utilizing ^(17)O isotopic labeling methods for solid-state nuclear magnetic resonance(NMR)investigations of metal oxides for lithium-ion batteries have yielded extensive insights into their structural and dynamic ***,we commence with a brief introduction to recent research on lithium-ion battery oxide materials studied using ^(17)O solid-state NMR *** we delve into a review of ^(17)O isotopic labeling methods for tagging oxygen sites in both the bulk and surfaces of metal *** last,the unresolved problems and the future research directions for advancing the ^(17)O labeling technique are discussed.

关键词： ^(17)O solid-state NMR ^(17)O isotopic labeling methods Bulk and surfaces of metal oxides DFT calculation

Ce6 nanoassemblies:Molecular mechanism and strategies for combinational anticancer therapy Special Collection:Aggregation-Induced Processes and Functions

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Aggregate 2024年第1期5卷 130-147页

作者： Yuwei Liu Shuting Xu Qingyang Lyu Yi Huang weiping Wang state Key Laboratory of Pharmaceutical Biotechnology The University of Hong KongHong KongChina Department of Pharmacology and Pharmacy Li Ka Shing Faculty of MedicineThe University of Hong KongHong KongChina Laboratory of Molecular Engineering and Nanomedicine Dr.Li Dak-Sum Research CentreThe University of Hong KongHong KongChina

Nowadays,cancer has become the leading cause of death worldwide,driving the need for effective therapeutics to improve patient *** therapy(PDT)has been widely applied as an antitumor modality,owing to its minimal invasiveness,localized tumor damage,and high safety ***,its efficacy is limited by poor stability of photosensitizers,inadequate tumor accumulation,and a complex tumor *** overcome these challenges,extensive endeavors have been made to explore the co-assembly of the widely used photosensitizer chlorin e6(Ce6)with various functional small molecules to enhance pharmacodynamic *** review provides a comprehensive overview of current studies on Ce6-based nanoparticles for effective PDT and precise delivery of functional *** self-assembly mechanism will be discussed in detail,with a focus on potential strategies for combinational therapy with PDT.

关键词： cancer treatment carrier-free chlorin e6(Ce6) light nanomedicine photodynamic therapy(PDT) selfassembly

Mechanical properties of steel mesh in anchor-mesh support for rocky tunnels

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Journal of Mountain Science 2024年第10期21卷 3487-3502页

作者： SUN Keguo JIA Jinglong XU weiping ZHANG Yu WANG Jinjin WANG Yichao LIU Yongkui Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSchool of Civil EngineeringSouthwest Jiaotong UniversityChengdu 610031China state Key Laboratory of Intelligent Geotechnics and Tunnelling Chengdu 610031China Chengdu Rail Transit Group Co. Ltd.Chengdu 610036China China Railway 14th Bureau Group 2nd Engineering Corporation Limited China Railway Construction Corporation LimitedTaian 271000China

Underground geotechnical engineering encounters persistent challenges in ensuring the stability and safety of surrounding rock structures, particularly within rocky tunnels. Rock reinforcement techniques, including the use of steel mesh, are critical to achieving this goal. However, there exists a knowledge gap regarding the comprehensive understanding of the mechanical behavior and failure mechanisms exhibited by steel mesh under diverse loading conditions. This study thoroughly explored the steel mesh's performance throughout the entire loading-failure process, innovating with detailed analysis and modeling techniques. By integrating advanced numerical modeling with laboratory experiments, the study examines the influence of varying reinforcement levels and geometric parameters on the steel mesh strength and deformation characteristics. Sensitivity analysis, employing gray correlation theory, identifies the key factors affecting the mesh performance, while a BP (Backpropagation) neural network model predicts maximum vertical deformation with high accuracy. The findings underscore the critical role of steel diameter and mesh spacing in optimizing peak load capacity, displacement, and energy absorption, offering practical guidelines for design improvements. The use of a Bayesian Regularization (BR) algorithm further enhances the predictive accuracy compared to traditional methods. This research provides new insights into optimizing steel mesh design for underground applications, offering an innovative approach to enhancing structural safety in geotechnical projects.

关键词： Tunnel Steel mesh BP neural network Anchor-mesh support Rock reinforcement technique

Black phosphorus quantum dots induce myocardial inflammatory responses and metabolic disorders in mice

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Journal of Environmental Sciences 2024年第3期137卷 53-64页

作者： Chao Shen Xiaoyan Ding Jinpeng Ruan Fengkai Ruan weiping Hu Jiyi Huang Chengyong He Yi Yu Zhenghong Zuo Department of Nephrology State Key Laboratory of Cellular Stress BiologySchool of Life SciencesFaculty of Medicine and Life SciencesFujian Clinical Research Center for Chronic Glomerular DiseaseThe First Affiliated Hospital of Xiamen UniversitySchool of MedicineXiamen UniversityXiamen 361102China

As an ultrasmall derivative of black phosphorus(BP)sheets,BP quantum dots(BP-QDs)have been effectively used in many ***,information on the cardiotoxicity induced by BP-QDs remains *** aimed to evaluate BP-QD-induced cardiac toxicity in *** examination of heart tissue sections was *** sequencing,real-time quantitative PCR(RT–qPCR),western blotting,and enzyme-linked immunosorbent assay(ELISA)assays were used to detect the m RNA and/or protein expression of proinfammatory cytokines,nuclear factor kappa B(NF-κB),phosphatidylinositol3 kinase-protein kinase B(PI3K-AKT),peroxisome proliferator-activated receptor gamma(PPARγ),and glucose/lipid metabolism pathway-related *** found that heart weight and heart/body weight index(HBI)were significantly reduced in mice after intragastric administration of 0.1 or 1 mg/kg BP-QDs for 28 *** addition,obvious infammatory cell infiltration and increased cardiomyocyte diameter were observed in the BP-QD-treated *** expression of proinfammatory cytokines and genes related to the NF-κB signaling pathway further confirmed that BP-QD exposure induced infammatory *** addition,BP-QD treatment also affected the PI3K-AKT,PPARγ,thermogenesis,oxidative phosphorylation,and cardiac muscle contraction signaling *** expression of genes related to glucose/lipid metabolism signaling pathways was dramatically affected by BP-QD exposure,and the effect was primarily mediated by the PPAR signaling *** study provides new insights into the toxicity of BP-QDs to human health.

关键词： BP-QDs Cardiac toxicity Infammatory responses NF-κB signaling pathway PPARγsignaling pathway Glucose/lipid metabolism

Process analytical technologies and self-optimization algorithms in automated pharmaceutical continuous manufacturing

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Chinese Chemical Letters 2024年第3期35卷 87-95页

作者： Peiwen Liu Hui Jin Yan Chen Derong Wang Haohui Yan Mingzhao Wu Fang Zhao weiping Zhu state Key Laboratory of Bioreactor Engineering Shanghai Key Laboratory of Chemical BiologySchool of PharmacyEast China University of Science and TechnologyShanghai 200237China state Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China Engineering Research Center of Pharmaceutical Process Chemistry Ministry of EducationSchool of PharmacyEast China University of Science and TechnologyShanghai 200237China

The pharmaceutical industry is now paying increased attention to continuous *** the revolution to continuous and automated manufacturing is deepening in most of the top pharma companies in the world,the advancement of automated pharmaceutical continuous manufacturing in China is relatively slow due to some key challenges including the lack of knowledge on the related technologies and shortage of qualified *** this review,emphasis is given to two of the crucial technologies in automated pharmaceutical continuous manufacturing,i.e.,process analytical technology(PAT)and self-optimizing *** work published in recent 5 years employing advanced PAT tools and self-optimization algorithms is introduced,which represents the great progress that has been made in automated pharmaceutical continuous manufacturing.

关键词： Pharmaceutical continuous manufacturing Automation Process analytical technology Self-optimization algorithm

Multistep continuous flow synthesis of Erlotinib

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Chinese Chemical Letters 2024年第4期35卷 371-375页

作者： Hui Jin Qin Cai Peiwen Liu Yan Chen Derong Wang weiping Zhu Yufang Xu Xuhong Qian state Key Laboratory of Bioreactor Engineering Shanghai Key Laboratory of Chemical BiologySchool of PharmacyEast China University of Science and TechnologyShanghai 200237China

Erlotinib is an orally administered, highly effective, specific epidermal growth factor receptor tyrosine kinase inhibitor, used to treat non-small cell lung cancer and pancreatic cancer. The traditional synthetic methods for Erlotinib exhibit long reaction time and safety concern. Herein, we describe a novel five-step route for the synthesis of Erlotinib in flow. These five steps comprise etherification, nitration, reduction,addition and cyclization reactions. All steps were optimized and converted to continuous flow process,which drastically reduces the reaction time and considerably improves the process safety as well as the total yield. Enabled by five continuous flow units, Erlotinib is efficiently afforded with an E-factor of 38,an overall yield of 83%, and a total residence time of 25.1 min. Majority steps in this process have been optimized for quantitative conversion, which offers the possibility of telescoping the entire process.

关键词： Erlotinib Continuous flow synthesis Microchannel flow reactor Process optimization Continuous nitration Continuous hydrogenation