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Chinese Chemical Letters 2024年第3期35卷 523-527页

作者： Pengfei Tan Chuanhui Zhu Jinjin Yang Shuang zhao Tao Xia mei-huan zhao Tao Han Zheng Deng Man-Rong Li Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-sen UniversityGuangzhou 510006China School of Science and Engineering The Chinese University of Hong KongShenzhen 518172China Institute of Physics Chinese Academy of SciencesBeijing 100190China School of Science Hainan UniversityHaikou 570228China

The intricate correlation between multiple degrees of freedom and physical properties is a fascinating area in solid state chemistry and condensed matter ***,we report a quantum-magnetic system BaNi_(2)V_(2)O_(8)(BNVO),in which the spin correlation was modulated by unusual oxidation state,leading to different magnetic *** BNVO was modified with topochemical reduction(TR)to yield TR-BNVO with partially reduced valance state of Ni^(+)in the two-dimensional NiO_(6)-honeycomb ***,the antiferromagnetic order is suppressed by the introduction of locally interposed Ni^(+)and oxygen vacancies,resulting in a ferromagnetic ground state with the transition temperature up to 710 K.A positive magnetoresistance(7.5%)was observed in the TR-BNVO at 40 K under 7 *** findings show that topological reduction is a powerful approach to engineer low-dimensional materials and accelerate the discovery of new quantum magnetism.

关键词： Layered honeycomb oxide Topochemical reduction Oxygen vacancies Ferromagnetism Magnetoresistance

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Calibration of local chemical pressure by optical probe

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National Science Review 2023年第9期10卷 258-269页

作者： Xiao Zhou mei-huan zhao Shan-Ming Yao Hongliang Dong Yonggang Wang Bin Chen Xianran Xing Man-Rong Li Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-sen University Center for High Pressure Science and Technology Advanced Research School of Materials Science and Engineering Peking University Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Solid State Chemistry University of Science and Technology Beijing School of Science Hainan University

Chemical stabilization of a high-pressure metastable state is a major challenge for the development of advanced *** chemical pressure(Pchem) can effectively simulate the effect of physical pressure(Pphy)) experimental calibration of the pressure passed to local structural motifs,denoted as local chemical pressure(Pchem-△) which significantly governs the function of solid materials,remains absent due to the challenge of probing *** we establish an innovative methodology to experimentally calibrate the Pchem-△and build a bridge between Pchemand Pphyvia an optical probe ***-selective Bi3+-traced REVO4(RE=Y,Gd) is adopted as a prototype to introduce Bi3+optical probes and on-site sense of the Pchem-△experienced by the *** cell compression of RE0.9gBi0.02VO4under Pphyis chemically simulated by smaller-ion substitution(Sc3+→RE3+) in *** consistent red shift(△λ) of the emission spectra of Bi3+,which is dominated by locally pressure-induced REO8dodecahedral variation in RE0.98Bi0.02VO4(Pphy) and RE0.98-xScxBi0.02VO4(Pchem-△),respectively,is evidence of their similar pressure-dependent local structure *** innovative △λ-based experimental calibration of Pchem-△in the crystal-field dimension portrays the anisotropic transmission of Pchemto the local structure and builds a bridge between Pchem-△and Pphyto guide a new perspective for affordable and practical interception of metastable states.

关键词： chemical pressure high pressure ion substitution optical parameter spectra shift pressure calibration

Differential Evolution Hemivariational Inequalities with Anti-periodic Conditions

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1143-1160页

作者： Jing zhao Chun mei GAN Zhen Hai LIU School of Mathematics and Quantitative Economics Guangxi University of Finance and EconomicsNanning 530003P.R.China Guangxi Colleges and Universities Key Laboratory of Optimization Control and Engineering Calculation Guangxi Minzu UniversityNanning 530006P.R.China

The goal of this paper is to deal with a new dynamic system called a differential evolution hemivariational inequality(DEHVI)which couples an abstract parabolic evolution hemivariational inequality and a nonlinear differential equation in a Banach ***,by apply ing surjectivity result for pseudomonotone multivalued mappins and the properties of Clarke's subgradient,we show the nonempty of the solution set for the parabolic hemivariational ***,some topological properties of the solution set are established such as boundedness,closedness and ***,we explore the upper semicontinuity of the solution ***,we prove the solution set of the system(DEHVI)is nonempty and the set of all trajectories of(DEHVI)is weakly compact in C(I,X).

关键词： Differential parabolic hemivariational inequality Clarke subdifferential hyperbolicparabolic system parabolic-parabolic system existence result

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Fluorescent carbon dots synthesized in solid phase and air for application in LEDs

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Nano Research 2024年第9期17卷 8495-8503页

作者： Wei-Jie Zheng zhao-Nan Sun Yi-Ming Wang huan-Ming Xiong Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200438China

Carbon dots(CDs)have been widely adopted as optical materials because of their excellent luminescent ***,most of the reported synthetic methods are conducted in solvents,especially hydrothermal/solvothermal reactions,leading to intractable problems such as toxic and flammable solvents,complex and inseparable by-products,and dangerously high pressures and ***-phase synthesis of CDs in air is an effective solution to overcome the above issues,but solid reactions always result in uncontrolled growth and agglomeration of *** this study,some inorganic salts are selected as catalysts for synthesizing CDs in solid states and air,which also play as dispersants to hinder CDs *** the meantime,some aromatic derivatives containing hydroxyl and amino groups are chosen as carbon sources,ground with the optimized catalyst,and then heated together in *** production yields are affected by the reaction time and reactant ratio,while the graphitization degrees of the CDs are determined by the reaction *** IG/ID value of their Raman spectra increases from 0.59 to 0.85,and the particle size decreases from 2.5 to 1.4 nm when the synthesis temperature is increased from 200 to 280℃.The as-prepared CDs show emission peaks ranging from 366 to 606 nm,with the photoluminescence(PL)quantum yield up to 53%.Their emission color variation mainly results from different carbon sources,which can be ascribed to the differences in the element composition,functional groups,and graphitic nitrogen content of these *** dispersing CDs of different concentrations into polyvinyl alcohol(PVA)and combining them with blue LEDs,cold,standard,and warm white light emitting devices(WLEDs)are prepared,with a color rendering index(CRI)up to *** the as-prepared CDs have antioxidant ability at high temperature,the as-prepared WLEDs have long lifespans,remaining the effective white luminescence after 72 h continuous work.

关键词： carbon dot solid-phase synthesis white LED photoluminescence inorganic salt catalysis

FedAdaSS: Federated Learning with Adaptive Parameter Server Selection Based on Elastic Cloud Resources

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 609-629页

作者： Yuwei Xu Baokang zhao huan Zhou Jinshu Su School of Computer National University of Defense TechnologyChangsha410000China

The rapid expansion of artificial intelligence(AI)applications has raised significant concerns about user privacy,prompting the development of privacy-preserving machine learning(ML)paradigms such as federated learning(FL).FL enables the distributed training of ML models,keeping data on local devices and thus addressing the privacy concerns of ***,challenges arise from the heterogeneous nature of mobile client devices,partial engagement of training,and non-independent identically distributed(non-IID)data distribution,leading to performance degradation and optimization objective bias in FL *** the development of 5G/6G networks and the integration of cloud computing edge computing resources,globally distributed cloud computing resources can be effectively utilized to optimize the FL *** the specific parameters of the server through the selection mechanism,it does not increase the monetary cost and reduces the network latency overhead,but also balances the objectives of communication optimization and low engagement mitigation that cannot be achieved simultaneously in a single-server framework of existing *** this paper,we propose the FedAdaSS algorithm,an adaptive parameter server selection mechanism designed to optimize the training efficiency in each round of FL training by selecting the most appropriate server as the parameter *** approach leverages the flexibility of cloud resource computing power,and allows organizers to strategically select servers for data broadcasting and aggregation,thus improving training performance while maintaining cost *** FedAdaSS algorithm estimates the utility of client systems and servers and incorporates an adaptive random reshuffling strategy that selects the optimal server in each round of the training *** analysis confirms the convergence of FedAdaSS under strong convexity and L-smooth assumptions,and comparative experiments within the FLSim framework demonstra

关键词： Machine learning systems federated learning server selection artificial intelligence of things non-IID data

Pressure-Induced Intermetallic Charge Transfer and Semiconductor- Metal Transition in Two-Dimensional AgRuO_(3)

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CCS Chemistry 2023年第4期5卷 934-946页

作者： Chuanhui Zhu Jinjin Yang Pengfei Shan mei-huan zhao Shuang zhao Cuiying Pei Bowen Zhang Zheng Deng Mark Croft Yanpeng Qi Lihong Yang Yonggang Wang Xiaojun Kuang Long Jiang Dao-Xin Yao Jin-Guang Cheng Man-Rong Li Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-sen UniversityGuangzhou 510275 Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190 School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210 College of Chemistry and Bioengineering Guilin University of TechnologyGuilin 541004 Department of Physics and Astronomy RutgersThe State University of New JerseyPiscatawayNJ 08854 ShanghaiTech Laboratory for Topological Physics ShanghaiTech UniversityShanghai 201210 Shanghai Key Laboratory of High-Resolution Electron Microscopy ShanghaiTech UniversityShanghai 201210 Center for High Pressure Science and Technology Advanced Research(HPSTAR) Beijing 100094 Guangdong Key Laboratory of Magnetoelectric Physics and Devices School of PhysicsSun Yat-sen UniversityGuangzhou 510275

The intricate correlation between charge degrees of freedom and physical properties is a fascinating area of research in solid state chemistry and condensed matter ***,we report on the pressureinduced successive charge transfer and accompanied resistive evolution in honeycomb layered ruthenate AgRuO_(3).Structural revisiting and spectroscopic analyses affirm the ilmenite type R-3 structure with mixed valence cations as Ag^(+1/+2)Ru^(+4/+5)O_(3) at ambient ***-situ pressure-and temperature-dependent resistance variation reveals a successive insulatormetal-insulator transition upon pressing,accompanied by unprecedented charge transfer between Ag and Ru under applied pressure,and a further structural phase transition in the insulator region at higher *** phenomena are also corroborated by in-situ pressure-dependent Raman spectra,synchrotron X-ray diffraction,bond valence sums,and electronic structure calculations,emphasizing the dominated rare Ag2+,and near zero thermal expansion in the ab-plane in the metallic zone mostly due to the Jahn-Teller effect of d9-Ag2+.The multiple electronic instabilities in AgRuO_(3) may offer new possibilities toward novel and unconventionally physical and chemical behaviors in strongly correlated honeycomb lattices.

关键词： intermetallic charge transfer semiconductor-metal transition honeycomb layered ruthenates high pressure

Evaluation of the value of combined detection of tumor markers CA724,carcinoembryonic antigen,CA242,and CA19-9 in gastric cancer

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1737-1744页

作者： Chong-mei Zhou Shao-Hua zhao Department of Clinical Laboratory Henan Provincial People's HospitalZhengzhou 450003Henan ProvinceChina

BACKGROUND Gastric cancer is a global health concern that poses a significant threat to human *** To detecting serum changes in carcinoembryonic antigen(CEA),carbohydrate antigens(CA)724,CA242,and CA19-9 expression among patients with gastric *** Eighty patients diagnosed with gastric cancer between January 2020 and January 2023 were included in the observation group,while 80 patients with benign gastric diseases were included in the control *** groups were tested for tumor markers(CA724,CEA,CA242,and CA19-9].Tumor marker indicators(CA724,CEA,CA242,and CA19-9)were compared between the two groups,assessing positive rates of tumor markers across various stages in the observation ***,single and combined detection of various tumor markers were *** The sensitivity,specificity,accuracy,positive predictive value,and negative predictive value observed for the combined detection of CA724,CEA,CA242,and CA19-9 were higher than those of CA724,CEA,CA242,and CA19-9 ***,the combined detection of CA724,CEA,CA242,and CA19-9 has a high diagnostic accuracy and could reduce the occurrence of missed or misdiagnosed cases,facilitating the early diagnosis and treatment of *** CA724,CEA,CA242,and CA19-9 serum levels in gastric cancer patients significantly surpassed those in non-gastric cancer patients(P<0.05).Their combined detection can improve the diagnostic accuracy for gastric cancer,warranting clinical promotion.

关键词： Biomarkers Serum Gastric cancer Diagnostic value

Will the State-owned Capital Transfer Policy Enhance the Sustainability of the Urban Employee Basic Pension Insurance Fund in China?

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China & World Economy 2024年第3期32卷 98-129页

作者： Jia Wang huan Liu mei Li Han Li School of Economics Xiamen UniversityChina School of Economics and Management Nanjing Agricultural UniversityChina School of Economics and Management Wuhan UniversityChina

To analyze the efect of the state-owned capital transfer policy on the sustainability of China's urban employee basic pension insurance fund(CUEBPIF),this study develops an actuarial model for pension *** results reveal the following:(i)Without policy intervention,the CUEBPIF would face a deficit in 2027 and a cumulative shortfall of RMB207.44 trillion by 2050,and the proportion of fiscal subsidies for the CUEBPIF in the total fiscal expenditure would increase to 12.86 percent in 2050.(i)Based on a delayed retirement policy,the transfer of 10 percent of state-owned capital can delay the onset of the fund deficit by 6 years,and the accumulated shortfall in 2050 would fall to RMB39.42 trillion,and the proportion of fiscal subsidies would decrease by I1.77 percentage points.(ii)The state-owned capital transfer policy can improve the sustainability of the CUEBPIF and reduce the burden of enterprise social security contributions when the transfer ratio increases to 20 percent.

关键词： burden of enterprise social security contributions delayed retirement policy state-owned capital transfer policy sustainability of basic pension insurance fund

A regression approach for seismic first-break picking

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Petroleum Science 2024年第3期21卷 1584-1596页

作者： huan Yuan San-Yi Yuan Jie Wu Wen-Jing Sang Yu-He zhao CNPC Key Laboratory of Geophysical Exploration China University of Petroleum(Beijing)Beijing 102249China Research Institute of Petroleum Exploration&Development—Northwest(NWGI) Key Laboratory of reservoir characterization of CNPCPetroChinaLanzhou 730020GansuChina

The picking efficiency of seismic first breaks(FBs)has been greatly accelerated by deep learning(DL)***,the picking accuracy and efficiency of DL methods still face huge challenges in low signal-to-noise ratio(SNR)*** address this issue,we propose a regression approach to pick FBs based on bidirectional long short-term memory(Bi LSTM)neural network by learning the implicit Eikonal equation of 3D inhomogeneous media with rugged topography in the target *** employ a regressive model that represents the relationships among the elevation of shots,offset and the elevation of receivers with their seismic traveltime to predict the unknown FBs,from common-shot gathers with sparsely distributed *** from image segmentation methods which automatically extract image features and classify FBs from seismic data,the proposed method can learn the inner relationship between field geometry and *** addition,the predicted results by the regressive model are continuous values of FBs rather than the discrete ones of the binary *** picking results of synthetic data shows that the proposed method has low dependence on label data,and can obtain reliable and similar predicted results using two types of label data with large *** picking results of9380 shots for 3D seismic data generated by vibroseis indicate that the proposed method can still accurately predict FBs in low SNR *** subsequent stacked profiles further illustrate the reliability and effectiveness of the proposed *** results of model data and field seismic data demonstrate that the proposed regression method is a robust first-break picker with high potential for field application.

关键词： First-break picking Low signal-to-noiseratio Regression BiLSTM Traveltime Geometry Noisy seismic data

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Improving the mechanical properties and inhibiting strain softening behavior of the biodegradable Zn-0.06Mg alloy via ECAP plus rolling processing

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Progress in Natural Science:Materials International 2024年第1期34卷 45-55页

作者： Chengwei Ji Aibin Ma Jinghua Jiang Dan Song huan Liu Liwen zhao Xuefei Fang College of Mechanics and Materials Hohai University Suqian Institute Hohai University

The practical application of micro-alloying Zn–Mg alloys is limited due to their poor mechanical properties and evident strain softening behavior. Therefore, this paper proposed the utilization of ECAP plus rolling processing as an innovative approach to potentially address these limitations. Herein, effects of ECAP and rolling processing on the microstructures, mechanical properties and strain softening behavior were investigated. It was found that the grain refinement achieved through 1-pass ECAP and 8-pass ECAP processing differed significantly, and subsequent rolling processing can further regulate grain size and dislocation distribution. The 1-pass ECAP plus cold rolling(1p-CR), 1-pass ECAP plus hot-cold rolling(1p-HC), and 8-pass ECAP plus hot-cold rolling(8p-HC) processed alloys exhibited heterostructure characterized by fine grains encircling coarse grains. Additionally, regions with high density dislocations were uniformly distributed alongside regions with low density dislocations. This unique microstructure promoted the accumulation and interaction of dislocation during deformation, resulting in the inhibition of strain softening behavior while maintaining high strength and high elongation. Therefore, the 1p-CR, 1p-HC, and 8p-HC alloys demonstrated excellent formability and mechanical stability while meeting the required mechanical properties for implant materials, which highlight their significant potential for practical applications.

关键词： Zn-Mg alloys ECAP Rolling Mechanical properties Strain softening behavior