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Organo-electroreduction enables arylcarboxylation of styrenes

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Science China Chemistry 2024年第11期67卷 3825-3832页

作者： Yanwei wang qian wang Zile Zhu Weikang Qi Youai Qiu State Key Laboratory and Institute of Elemento-Organic Chemistry Frontiers Science Center for New Organic Matter Haihe Laboratory of Sustainable Chemical Transformations College of Chemistry Nankai University

Electroreduction offers an alternative to generate high active intermediates from electrophiles(halides, alkenes, etc.) in organic synthesis. However, it still remains challenge to enable the transformations in controlled fashion for substrates with similar reduction potentials. Herein, an electroreductive arylcarboxylation of styrenes with aryl halides and CO2promoted by an organomediator has been developed. The reaction exhibits the remarkable reactivity control between styrenes and aryl halides bearing very similar reduction potentials, which is enabled by the addition of a simple organic mediator. The mediated process for different kinds of aryl halides(iodides and bromides) could be achieved by simply tuning the electronic effect of the skeleton of naphthalene. This protocol displays a broad substrate scope and the extension to late-stage modification of biorelevant molecules and their derivatives showed a bright prospect. Moreover, density functional theory(DFT) calculations and mechanistic studies have been conducted and provide solid support to rationalize the selectivity and reactivity control observed.

关键词： CO2 utilization reductive organo-mediator carboxylation electroreduction aryl halides

Boring holes in Au nanoplates by active surface etching

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Nano Research 2024年第9期17卷 8610-8617页

作者： Haiyang Hu Yuntao wang qian wang Xudong Peng An Su Hong wang Hongyu Chen Institute of Advanced Synthesis(IAS)and School of Chemistry and Molecular Engineering Jiangsu National Synergetic Innovation Centre for Advanced MaterialsNanjing Tech UniversityNanjing 211816China Department of Environmental Science and Engineering University of Science and Technology of ChinaHefei 230026China Department of Chemistry School of Science and Key Laboratory for Quantum Materials of Zhejiang ProvinceResearch Center for Industries of the FutureWestlake UniversityHangzhou 310030China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China

In contrast to the conventional etching that makes nanoparticles rounder and our previous sharpening etching mode that causes serrated edges,here,we developed a new boring etching mode that targets the faces of Au nanoplates to make *** critical factors are the pre-incubation step with the ligand 2-mercapto-5-benzimidazolecarboxylic acid(MBIA)and the subsequent removal of excess ligands in the ***,etching is focused onto the few sites with initial loss of ligands,which cannot be quickly *** choice of ligand MBIA is also of importance,as it carries negative charge and repels each *** inability of forming a dense layer probably plays a critical role in the site-selectivity for faces,because ligands at the higher curvature edges and corners are expected to have less *** etching results from the comproportionation reaction between Au3+and Au0 in the nanoplates,where Br-coordination to Au and the extra stabilization from cetyltrimethylammonium bromide(CTAB)are *** believe that the ability of boring holes is an important tool for future synthetic designs.

关键词： Au nanoplates active surface etching boring etching mode cetyltrimethylammonium bromide(CTAB)passivation holes

USP45 acts as an oncogene to regulate the proliferation of esophageal cancer cells

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Genes & Diseases 2024年第5期11卷 44-47页

作者： Kai Li qian wang Hua Bian Zhang Zhongjing College of Chinese Medicine Henan Key Laboratory of Zhang Zhongjing Formulae and Herbs for ImmunoregulationNanyang Institute of TechnologyNanyangHenan 473004China College of Orthopaedics and Traumatology Henan University of Chinese MedicineZhengzhouHenan 450046China

Deubiquitinases(DUBs)are a class of enzymes that are able to reverse the process of ubiquitination.1 Extensive research has revealed that there are more than 100 DUBs found in humans,which are classified into seven main families:ubiquitin-specific proteases(USPs),ubiquitin carboxyl-terminal hydrolases,the Machado-Joseph disease domain superfamily,the otubain/ovarian tumor-domain containing proteins,the ZUFSP(Zinc finger with UFM1-specific peptidase domain protein)family,the JAB1/MPN/MOV34 proteases,and the novel motif interacting with ubiquitin-containing DUB *** DUBs are cysteine proteases,except the JAB1/MPN/MOV34 proteases,which are Zn^(2+) metalloproteases.

关键词： esophageal cancer Zinc

Recent Advances in Photochemical/Electrochemical Carboxylation of Olefins with CO_(2)

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Chinese Journal of Chemistry 2024年第18期42卷 2249-2266页

作者： qian wang Yanwei wang Min Liu Ganghui Chu Youai Qiu Xinjiang Laboratory of Native Medicinal and Edible Plant Resources Chemistry College of Chemistry and Environmental ScienceKashiUniversityKashiXinjiang844000China state Key Laboratory and Institute of Elemento-Organic Chemistry Frontiers Science Centerfor New Organic MatterCollege of Chemistry NankaiUniversity94WeijinRoadTianjin300071China

CO_(2) is an abundant,nontoxic,and renewable C1 feedstock in synthetic *** carboxylation of readily available olefins incorporating CO_(2) is regarded as a promising strategy to access high value-added carboxylic acids as well as CO_(2) ***,due to the thermodynamic stability and kinetic inertness of CO_(2) and the difficulty in controlling the regioselectivity,the carboxylation of olefins with CO_(2) still remains ***-type functionalization with olefins represented a powerful protocol and enabled the development of novel transformations in this *** recently,the advance of new technology,such as photoredox catalysis and the renaissance of electrochemistry in organic synthesis,offered access to unique chemical reactivities of radical precursors and provided new solutions to the functionalization of olefins.

关键词： CO_(2) Carboxylation Olefins Photocatalysis Electrocatalysis Radical Reduction Difunctionalization

Joined AZ31B Magnesium Alloys with Ag Interlayer by Ultrasonic-Induced Transient Liquid Phase Bonding in Air

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1177-1185页

作者： qian wang Peng Yu Haoran Lin Chongzhi Guo Xiaoqiang Hu Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341119China School of Rare Earths University of Science and Technology of ChinaHefei230026China Shenyang 7D New Materials Equipment Co.LTD. Shenyang110076China Shenyang National Laboratory of Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

AZ31B magnesium alloys are commonly used in lightweight structures of automobile and aerospace *** this work,the ultrasonic-induced transient liquid phase bonding technique is deployed to joint AZ31B magnesium alloys at 490℃ with Ag interlayer in the *** effect of ultrasonic vibration on microstructure and mechanical properties of welding seam is *** vibration duration increases,the width of the welding seam increases firstly and then *** the ultrasound vibration sustained for one second,the eutectic reaction occurred in the contacting interface between Ag interlayer and the base metal AZ31B,resulting in formation of liquid phase and metallurgical *** the ultrasound vibration sustained for seven second,the width of the welding seam increased to a maximum of about 303.1μm and the average shear bond strength of the welding joint attained the peak value of about 66.87 *** the ultrasound vibration sustained over seven seconds,the liquid phase is gradually squeezed out and the width of the welding seam decreases.α-Mg and AgMg_(3) can be observed in the welding *** analysis shows thatα-Mg has a certain strengthening *** whole process of appearance,growth and integration ofα-Mg is analyzed.

关键词： Ultrasonic bonding Magnesium alloy Silver Microstructure Intermetallic compound

SwiftTheft: A Time-Efficient Model Extraction Attack Framework Against Cloud-Based Deep Neural Networks

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Chinese Journal of Electronics 2024年第1期33卷 90-100页

作者： Wenbin YANG Xueluan GONG Yanjiao CHEN qian wang Jianshuo DONG School of Cyber Science and Engineering Wuhan University School of Computer Science Wuhan University College of Electrical Engineering Zhejiang University

With the rise of artificial intelligence and cloud computing, machine-learning-as-a-service platforms,such as Google, Amazon, and IBM, have emerged to provide sophisticated tasks for cloud applications. These proprietary models are vulnerable to model extraction attacks due to their commercial value. In this paper, we propose a time-efficient model extraction attack framework called Swift Theft that aims to steal the functionality of cloud-based deep neural network models. We distinguish Swift Theft from the existing works with a novel distribution estimation algorithm and reference model settings, finding the most informative query samples without querying the victim model. The selected query samples can be applied to various cloud models with a one-time selection. We evaluate our proposed method through extensive experiments on three victim models and six datasets, with up to 16 models for each dataset. Compared to the existing attacks, Swift Theft increases agreement(i.e., similarity) by 8% while consuming 98% less selecting time.

关键词： Performance evaluation Cloud computing Analytical models Computational modeling Estimation Artificial neural networks Artificial intelligence

V-MOF-derived V_(2)O_(5) nanoparticles-modified carbon fiber cloth-based dendrite-free anode for high-performance lithium metal batteries

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Chinese Journal of Chemical Engineering 2024年第7期71卷 13-23页

作者： Tao Wei Mengting wang Yanyan Zhou Xingtong Guo Sijia wang Ye Liu Cheng Sun qian wang School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China

At present,commercial Li-ion batteries are hardly to satisfy the growing demand for high energy density,for this purpose,lithium metal batteries have attracted worldwide attention in recent ***,its practical applications are hindered by the formation of Li dendrites and volume effect during Li plating/stripping process,which leads to a lot of safety ***,we first employed MOF-derived V_(2)O_(5) nanoparticles to decorate the carbon fiber cloth(CFC)backbone to acquire a lithiophilic 3D porous conductive framework(CFC@V_(2)O_(5)).Subsequently,the CFC@V_(2)O_(5) skeleton was permeated with molten Li to prepare CFC@V_(2)O_(5)@Li composite *** CFC@V_(2)O_(5)@Li composite anode can be stably cycled for more than 1650 h at high current density(5 mA·cm^(-2))and areal capacity(5 mA·h·cm^(–2)).The prepared full cell can initially maintain a high capacity of about 143 mA·h·g^(-1) even at a high current density of 5 C,and can still maintain 114 mA·h·g^(-1) after 1000 cycles.

关键词： Three-dimensional(3D)conductive frameworks Lithium metal anode Lithiophilic material MOF-derived materials Prestoring lithium

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Fairness in machine learning: definition, testing,debugging, and application

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Science China(Information Sciences) 2024年第9期67卷 41-61页

作者： Xuanqi GAO Chao SHEN Weipeng JIANG Chenhao LIN qian LI qian wang Qi LI Xiaohong GUAN Faculty of Electronic and Information Engineering Xi'an Jiaotong University School of Cyber Science and Engineering Wuhan University Institute for Network Sciences and Cyberspace Tsinghua University

In recent years, artificial intelligence technology has been widely used in many fields, such as computer vision, natural language processing and autonomous driving. Machine learning algorithms, as the core technique of AI, have significantly facilitated people's lives. However, underlying fairness issues in machine learning systems can pose risks to individual fairness and social security. Studying fairness definitions, sources of problems, and testing and debugging methods of fairness can help ensure the fairness of machine learning systems and promote the wide application of artificial intelligence technology in various fields. This paper introduces relevant definitions of machine learning fairness and analyzes the sources of fairness problems. Besides, it provides guidance on fairness testing and debugging methods and summarizes popular datasets. This paper also discusses the technical advancements in machine learning fairness and highlights future challenges in this area.

关键词： artificial intelligence security machine learning security machine learning fairness model testing model debugging

Controlling molecular assembly on time scale:Time-dependent multicolor fluorescence for information encryption

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Chinese Chemical Letters 2024年第7期35卷 336-340页

作者： Zixi Zou Jingyuan wang Yian Sun qian wang Da-Hui Qu Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Dynamic assembly on time scale is common in biological systems but rare for artificial materials,especially for smart luminescent *** molecular assembly in a spatio-temporal manner and resulting in white-light-including multicolor fluorescence with time-dynamic features remains ***,controlling molecular assembly on time scale is achieved by integrating a pH-responsive motif to a transient alkaline solution which is fabricated by activators(NaOH)and deactivators(esters),leading to automatic assembly on time scale and time-dependent multicolor fluorescence changing from blue to white and *** kinetics of the assembly process is dependent on the ester hydrolysis process,which can be controlled by varying ester concentrations,temperature,initial pH,stirring rate and ester *** dynamic fluorescent system can be further developed for intelligent fluorescent materials such as fluorescent ink,three-dimension(3D)codes and even four-dimension(4D)codes,exhibiting a promising potential for information encryption.

关键词： Supramolecular chemistry Multicolor fluorescence White light emission Time-dependent fluorescence Information encryption

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