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Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

Science China Chemistry 2025年

作者： Shuai Zhang Pei-Zhi Liu Yan-Bo Li Qi Zhang Jun-Zhao Xiao yi-Fan wang Tian-Yu Wei Jia-Wei Jiang Ye wang Qian Peng Liang yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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RF Optimizer Model for Predicting Compressive Strength of Recycled Concrete

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 215-223页

作者： LIU Lin wang Liuyan wang Hui SUN Huayue School of Civil Engineering and Architecture Shenyang UniversityShenyang 110000China

Traditional machine learning(ML)encounters the challenge of parameter adjustment when predicting the compressive strength of reclaimed *** address this issue,we introduce two optimized hybrid models:the Bayesian optimization model(B-RF)and the optimal model(Stacking model).These models are applied to a data set comprising 438 observations with five input variables,with the aim of predicting the compressive strength of reclaimed ***,we evaluate the performance of the optimized models in comparison to traditional machine learning models,such as support vector regression(SVR),decision tree(DT),and random forest(RF).The results reveal that the Stacking model exhibits superior predictive performance,with evaluation indices including R2=0.825,MAE=2.818 and MSE=14.265,surpassing the traditional ***,we also performed a characteristic importance analysis on the input variables,and we concluded that cement had the greatest influence on the compressive strength of reclaimed concrete,followed by ***,the Stacking model can be recommended as a compressive strength prediction tool to partially replace laboratory compressive strength testing,resulting in time and cost savings.

关键词： machine learning recycled concrete compressive strength

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新时代高校师德失范行为惩戒的法治化构造

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黑龙江高教研究 2025年第1期43卷 15-21页

作者：王羿程中国人民公安大学北京100038

高校师德失范行为惩戒既是新时代师德师风建设的核心部分,更是推进教育治理现代化的关键命题。当前高校师德失范行为惩戒面临两个方面困境:一是制度层面的供给不足;二是在实施机制中存在参与通道不畅、教师权利的实效性救济困难等问题... 详细信息

高校师德失范行为惩戒既是新时代师德师风建设的核心部分,更是推进教育治理现代化的关键命题。当前高校师德失范行为惩戒面临两个方面困境:一是制度层面的供给不足;二是在实施机制中存在参与通道不畅、教师权利的实效性救济困难等问题。应当明确,法治既是新时代教育治理现代化的基本目标与重要内容,也是高校教育治理现代化的基本路径,更是高校进行师德失范行为惩戒必须遵循的基本模式。通过法治化的建构路径,于静态维度准确界定惩戒的启动条件,划定惩戒的适用范围;于动态维度畅通多元主体的利益诉求表达通道。进而,在实践维度强化高校自主化、专业化实施师德失范行为惩戒的能力,在中国式现代化的时代格局下,有力推进高校教育治理现代化。

关键词：教育治理现代化师德失范行为惩戒制度困境法治化建构阶层化构造

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Multi-Stage Voltage Control Optimization Strategy for Distribution Networks Considering Active-Reactive Co-Regulation of Electric Vehicles

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Energy Engineering 2025年第1期122卷 221-242页

作者： Shukang Lyu Fei Zeng Huachun Han HuiyuMiao yi Pan Xiaodong Yuan Electric Power Research Institute State Grid Jiangsu Electric Power Co.Ltd.Nanjing211103China

The high proportion of uncertain distributed power sources and the access to large-scale random electric vehicle(EV)charging resources further aggravate the voltage fluctuation of the distribution network,and the existing research has not deeply explored the EV active-reactive synergistic regulating characteristics,and failed to realize themulti-timescale synergistic control with other regulatingmeans,For this reason,this paper proposes amultilevel linkage coordinated optimization strategy to reduce the voltage deviation of the distribution ***,a capacitor bank reactive power compensation voltage control model and a distributed photovoltaic(PV)activereactive power regulationmodel are ***,an external characteristicmodel of EVactive-reactive power regulation is developed considering the four-quadrant operational characteristics of the *** optimization model of the distribution network is then constructed considering the time-series coupling constraints of multiple types of voltage regulators.A multi-timescale control strategy is proposed by considering the impact of voltage regulators on active-reactive EV energy consumption and PV energy ***,a four-stage voltage control optimization strategy is proposed for various types of voltage regulators with multiple time ***-objective optimization is solved with the improvedDrosophila algorithmto realize the power fluctuation control of the distribution network and themulti-stage voltage control *** results validate that the proposed voltage control optimization strategy achieves the coordinated control of decentralized voltage control resources in the distribution *** effectively reduces the voltage deviation of the distribution network while ensuring the energy demand of EV users and enhancing the stability and economic efficiency of the distribution network.

关键词： Electric vehicle(EV) distribution network multi-stage optimization active-reactive power regulation voltage control

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复杂误差的仿真及其应用

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系统仿真学报 2003年第6期15卷 780-782页

作者：易东云王正明童丽国防科技大学数学与系统科学系湖南长沙410073

提出采用最优节点的样条函数模型对复杂误差建立数学模型,该模型通过最优节点个数和节点距的自适应调整,精确分离复杂误差数据中的次低频误差和随机误差,对次低频误差通过样条参数的统计模型实现,对随机误差采用自回归模型实现,并综合... 详细信息

提出采用最优节点的样条函数模型对复杂误差建立数学模型,该模型通过最优节点个数和节点距的自适应调整,精确分离复杂误差数据中的次低频误差和随机误差,对次低频误差通过样条参数的统计模型实现,对随机误差采用自回归模型实现,并综合得到复杂误差数据的仿真。最后,利用该仿真模型讨论了复杂误差对数据融合系统输出精度的影响。

关键词：复杂误差样余函数仿真精度

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AI-Enhanced Secure Data Aggregation for Smart Grids with Privacy Preservation

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Computers, Materials & Continua 2025年第1期82卷 799-816页

作者： Congcong wang Chen wang Wenying Zheng Wei Gu School of Software Nanjing University of Information Science and TechnologyNanjing210044China School of Information Science and Engineering Zhejiang Sci-Tech UniversityHangzhou310018China State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025China School of Computer Science and Technology(School of Artificial Intelligence) Zhejiang Sci-Tech UniversityHangzhou310018China School of Computer Science(School of Cyber Science and Engineering) Nanjing University of Information Science and TechnologyNanjing210044China

As smart grid technology rapidly advances,the vast amount of user data collected by smart meter presents significant challenges in data security and privacy *** research emphasizes data security and user privacy concerns within smart ***,existing methods struggle with efficiency and security when processing large-scale *** efficient data processing with stringent privacy protection during data aggregation in smart grids remains an urgent *** paper proposes an AI-based multi-type data aggregation method designed to enhance aggregation efficiency and security by standardizing and normalizing various data *** approach optimizes data preprocessing,integrates Long Short-Term Memory(LSTM)networks for handling time-series data,and employs homomorphic encryption to safeguard user *** also explores the application of Boneh Lynn Shacham(BLS)signatures for user *** proposed scheme’s efficiency,security,and privacy protection capabilities are validated through rigorous security proofs and experimental analysis.

关键词： Smart grid data security privacy protection artificial intelligence data aggregation

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[Progress in applications of ambient ionization mass spectrometry for lipids identification]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 22-32页

作者： Xiao-Rong wang yi-Yan yin Jin Ouyang Na Na Key Laboratory of Radiopharmaceuticals Ministry of Education College of Chemistry Beijing Normal University Beijing 100875 China. Department of Chemistry College of Arts and Sciences Beijing Normal University Zhuhai 519087 China.

Lipids are indispensable components of living organisms and play pivotal roles in cell-membrane fluidity, energy provision, and neurotransmitter transmission and transport. Lipids can act as potential biomarkers of diseases given their abilities to indicate cell-growth status. For example, the lipid-metabolism processes of cancer cells are distinct from those of normal cells owing to their rapid proliferation and adaptation to ever-changing biological environments. As a result, the ability to rapidly detect, identify, and monitor lipid components is critical for tracking life-related processes and may enhance cancer diagnosis and treatment efficacy. Mass spectrometry (MS) is regarded to be among the most efficient methods for directly obtaining molecular-structural information, and is distinctly advantageous for identifying lipids. Recent years have witnessed the emergence of ambient mass spectrometry (AMS), which enables direct analyte sampling and ionization without the need for sample preprocessing. These characteristics endow AMS with special advantages for identifying and monitoring lipids. Furthermore, the ongoing development of soft ionization technologies has led to the widespread use of AMS for the detection of complex and diverse lipid molecules. Electrospray ionization (ESI) is a gentle ionization method that can be used to detect medium-to-high-polarity compounds and provide detailed chemical information for lipids by producing a fine mist of charged droplets from a liquid sample. Consequently, a series of ESI-based ionization methods have been developed for fabricating different AMS systems capable of rapidly detecting lipids in a simple manner. For example, desorption electrospray ionization (DESI) is among the most extensively employed ambient ionization techniques, and has been used to detect a wide range of samples, including solids, liquids, and gases. DESI involves spraying a charged solvent onto the surface of a sample, after which the solvent is

关键词： ambient mass spectrometry (AMS) ionization techniques lipid lipid fine structure tandem mass spectrometry (MS/MS)

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Wafer‑Scale Vertical 1D GaN Nanorods/2D MoS_(2)/PEDOT:PSS for Piezophototronic Effect‑Enhanced Self‑Powered Flexible Photodetectors

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Nano-Micro Letters 2025年第3期17卷 102-116页

作者： Xin Tang Hongsheng Jiang Zhengliang Lin Xuan wang Wenliang wang Guoqiang Li State Key Laboratory of Luminescent Materials and Devices South China University of TechnologyGuangzhou 510640People’s Republic of China Department of Electronic Materials School of Materials Science and EngineeringSouth China University of TechnologyGuangzhou 510640People’s Republic of China

van der Waals(vdW)heterostructures constructed by lowdimensional(0D,1D,and 2D)materials are emerging as one of the most appealing systems in next-generation flexible ***,hand-stacked vdW-type photodetectors are not compatible with large-areaarray fabrication and show unimpressive performance in self-powered ***,vertical 1D GaN nanorods arrays(NRAs)/2D MoS_(2)/PEDOT:PSS in wafer scale have been proposed for self-powered flexible photodetectors arrays *** as-integrated device without external bias under weak UV illumination exhibits a competitive responsivity of 1.47 A W^(−1)and a high detectivity of 1.2×10^(11)Jones,as well as a fast response speed of 54/71μs,thanks to the strong light absorption of GaN NRAs and the efficient photogenerated carrier separation in type-II ***,the strain-tunable photodetection performances of device have been ***,the device at−0.78%strain and zero bias reveals a significantly enhanced photoresponse with a responsivity of 2.47 A W^(−1),a detectivity of 2.6×10^(11)Jones,and response times of 40/45μs,which are superior to the state-of-the-art self-powered flexible *** work presents a valuable avenue to prepare tunable vdWs heterostructures for self-powered flexible photodetection,which performs well in flexible sensors.

关键词： Vertical nanorod arrays van der Waals heterostructure Piezophototronic effect Self-powered photodetection Flexible sensors

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Silk damping in scalar-induced gravitational waves: a novel probe for new physics

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 79-85页

作者： Yan-Heng Yu Sai wang Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences School of Physics University of Chinese Academy of Sciences

Silk damping is well known in the study of cosmic microwave background（CMB） and accounts for suppression of the angular power spectrum of CMB on large angular multipoles. In this article, we study the effect of Silk damping on the scalar-induced gravitational waves（SIGWs）. Resulting from the dissipation of cosmic fluid, the Silk damping notably suppresses the energydensity spectrum of SIGWs on scales comparable to a diffusion scale at the decoupling time of weakly-interacting particles. The effect offers a novel observable for probing the underlying particle interaction, especially for those mediated by heavy gauge bosons beyond the standard model of particles. We anticipate that pulsar timing arrays are sensitive to gauge bosons with mass ～10～3-10～4 GeV, while space-and ground-based interferometers to those with mass ～10～7-1012GeV, leading to essential complements to on-going and future experiments of high-energy physics.

关键词： scalar-induced gravitational waves Silk damping new physics

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Mechanism of inflammatory response and therapeutic effects of stem cells in ischemic stroke:current evidence and future perspectives

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Neural Regeneration Research 2025年第1期20卷 67-81页

作者： Yubo wang Tingli Yuan Tianjie Lyu Ling Zhang Meng wang Zhiying He Yongjun wang Zixiao Li Vascular Neurology Department of NeurologyBeijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Shanghai Engineering Research Center of Stem Cells Translational Medicine ShanghaiChina National Center for Healthcare Quality Management in Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Institute for Regenerative Medicine Shanghai East HospitalSchool of Life Sciences and TechnologyTongji UniversityShanghaiChina Chinese Institute for Brain Research BeijingChina Research Unit of Artificial Intelligence in Cerebrovascular Disease Chinese Academy of Medical SciencesBeijingChina Beijing Engineering Research Center of Digital Healthcare for Neurological Diseases BeijingChina

Ischemic stroke is a leading cause of death and disability worldwide,with an increasing trend and tendency for onset at a younger ***,in particular,bears a high burden of stroke *** recent years,the inflammatory response after stroke has become a research hotspot:understanding the role of inflammatory response in tissue damage and repair following ischemic stroke is an important direction for its *** review summarizes several major cells involved in the inflammatory response following ischemic stroke,including microglia,neutrophils,monocytes,lymphocytes,and ***,we have also highlighted the recent progress in various treatments for ischemic stroke,particularly in the field of stem cell ***,understanding the complex interactions between inflammation and ischemic stroke can provide valuable insights for developing treatment strategies and improving patient *** cell therapy may potentially become an important component of ischemic stroke treatment.

关键词： cell therapy immune cell inflammatory ischemic stroke stem cell

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