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Phase engineering of Ni-Mn binary layered oxide cathodes for sodiumion batteries

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Journal of Energy Chemistry 2024年第4期91卷 501-511页

作者： Feifei Hong xin Zhou Xiaohong Liu Guilin feng heng Zhang Weifeng Fan Bin Zhang Meihua Zuo Wangyan xing Ping Zhang Hua Yan Wei Xiang College of Materials and Chemistry&Chemical Engineering Chengdu University of TechnologyChengdu 610059SichuanChina College of Chemical Engineering Sichuan UniversityChengdu 610065SichuanChina Research Institute for Electronic Science(RIES)and Division of Information Science and Technology Graduate School of Information Science and TechnologyHokkaido UniversityN20W10SapporoHokkaido 001-0020Japan School of Materials Science and Engineering Suzhou University of Science and TechnologySuzhou 215009JiangsuChina Yibin Libode New Materials Co. Ltd.Yibin 644200SichuanChina Engineering Research Center of the Ministry of Education for Advanced Battery Materials School of Metallurgy and EnvironmentCentral South UniversityChangsha 410083HunanChina

Nickel-manganese binary layered oxides with high working potential and low cost are potential candidates for sodium-ion batteries,but their electrochemical properties are highly related to compositional *** composite materials with various phase structures of P3,P2/P3,P2,P2/O3,and P2/P3/O3 were synthesized by manipulating the sodium content and calcination conditions,leading to the construction of a synthetic phase diagram for Na_(x)Ni_(0.25)Mn_(0.75)O_(2)(0.45≤x≤1.1).Then,we compared the electrochemical characteristics and structural evolution during the desodiation/sodiation process of P2,P2/P3,P2/03,and P2/P3/O3-Na_(x)Ni_(0.25)Mn_(0.75)O_(2).Among them,P2/P3-Na0.75Ni0.25Mn0.75O2exhibits the best rate capability of 90.9 mA h g^(-1)at 5 C,with an initial discharge capacity of 142.62 mA h g^(-1)at 0.1 C and a capacity retention rate of 78.25%after 100 cycles at 1 C in the voltage range of 2-4.3 *** observed superior sodium storage performance of P2/P3 hybrids compared to other composite phases can be attributed to the enhanced Na^(+)transfer dynamic,reduction of the Jahn-teller effect,and improved reaction reversibility induced by the synergistic effect of P2 and P3 *** systematic research and exploration of phases in Na_(x)Ni_(0.25)Mn_(0.75)O_(2)provide new sights into high-performance nickel-manganese binary layered oxide for sodium-ion batteries.

关键词： Phase engineering Ni-Mn layered oxide Cathode Sodium-ion batteries

NHC-derived carbon-centered luminescent radicals with shortwavelength emission via suppression of Kasha's rule

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Science China Chemistry 2024年第8期67卷 2679-2685页

作者： Can Chen xin Li xinhua Ouyang Ying-feng Han Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China College of Material Engineering Fujian Agriculture and Forestry University Fuzhou 350108China

Luminescent organic radicals have garnered increasing attention owing to their versatile applications in sensing, imaging, and organic light-emitting diodes(OLEDs), attributed to their unique emission properties originating from the doublet spin ***, the natural narrow bandgap of organic free radicals typically limits their emission to the long-wavelength *** luminescent organic radicals with short-wavelength emission remains a significant challenge. Herein, a series of carbon-centered radicals with short-wavelength emission(383–476 nm) by combining N-heterocyclic carbenes with various polycyclic aromatic hydrocarbons(PAHs)(2-naphthyl, 2a~Ⅰ and 2b~Ⅰ;2-phenanthryl, 2a~Ⅱand 2b~Ⅱ;2-anthryl, 2a~Ⅲand 2b~Ⅲ;3-phenanthryl, 2a~Ⅳand 2b~Ⅳ). Theoretical calculations reveal that the introduction of PAHs significantly increases the ΔE_(D2-D1) in 2a^(Ⅰ–Ⅲ)and 2b^(Ⅰ–Ⅲ)compared to that in phenyl-derived radical congeners. Consequently, the internal transition from D2 to D1 is impeded, leading to a high yield of D2 emission and a suppressed Kasha's rule, thereby overcoming the limitations imposed by their narrow bandgap. For 2a~Ⅳ and 2b~Ⅳ, despite a moderately large ΔED2-D1value, the ΔED3-D1value exceeds 1 e V, indicating that their emission likely originates from the D3 state. Furthermore, we utilized 2a~Ⅲand 2b~Ⅲ as emissive materials in OLEDs,resulting in blue emissions with external quantum efficiencies of 7.5% and 6.5%, respectively.

关键词： N-heterocyclic carbenes luminescent organic molecules carbon-centered radicals short-wavelength emission

Health diagnosis of ultrahigh arch dam performance using heterogeneous spatial panel vector model

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Water Science and Engineering 2024年第2期17卷 177-186页

作者： Er-feng Zhao xin Li Chong-shi Gu The National Key Laboratory of Water Disaster Prevention Hohai UniversityNanjing 210098China NationalEngineering Research Centerof Water Resources Eficient Utilization and Engineering Safety Hohai UniversityNanjing 20098China

Currently,more than ten ultrahigh arch dams have been constructed or are being constructed in *** control is essential to long-term operation of these *** study employed the flexibility coefficient and plastic complementary energy norm to assess the structural safety of arch dams.A comprehensive analysis was conducted,focusing on differences among conventional methods in characterizing the structural behavior of the Xiaowan arch dam in ***,the spatiotemporal characteristics of the measured performance of the Xiaowan dam were explored,including periodicity,convergence,and time-effect *** findings revealed the governing mechanism of main ***,a heterogeneous spatial panel vector model was developed,considering both common factors and specific factors affecting the safety and performance of arch *** model aims to comprehensively illustrate spatial heterogeneity between the entire structure and local regions,introducing a specific effect quantity to characterize local deformation ***,the proposed model was applied to the Xiaowan arch dam,accurately quantifying the spatiotemporal heterogeneity of dam ***,the spatiotemporal distri-bution characteristics of environmental load effects on different parts of the dam were reasonably *** of the model prediction enhances its credibility,leading to the formulation of health diagnosis criteria for future long-term operation of the Xiaowan *** findings not only enhance the predictive ability and timely control of ultrahigh arch dams'performance but also provide a crucial basis for assessing the effectiveness of engineering treatment measures.

关键词： Ultrahigh arch dam Structural performance Deformation behavior Diagnosis criterion Panel data model

A program logic for obstruction-freedom

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Frontiers of Computer Science 2024年第06期18卷 1-16页

作者： LI Zhao-Hui feng xin-Yu School of Computer Science and Technology University of Science and Technology of China Department of Computer Science and Technology Nanjing University State Key Laboratory for Novel Software Technology Nanjing University

Though obstruction-free progress property is weaker than other non-blocking properties including lock-freedom and wait-freedom, it has advantages that have led to the use of obstruction-free implementations for software transactional memory (STM) and in anonymous and fault-tolerant distributed computing. However, existing work can only verify obstruction-freedom of specific data structures (e.g., STM and list-based algorithms).In this paper, to fill this gap, we propose a program logic that can formally verify obstruction-freedom of practical implementations, as well as verify linearizability, a safety property, at the same time. We also propose informal principles to extend a logic for verifying linearizability to verifying obstruction-freedom. With this approach, the existing proof for linearizability can be reused directly to construct the proof for both linearizability and ***, we have successfully applied our logic to verifying a practical obstruction-free double-ended queue implementation in the first classic paper that has proposed the definition of obstruction-freedom.

关键词： verification program logic progress properties obstruction-freedom concurrent objects

Research on IPFS Image Copyright ProtectionMethod Based on Blockchain

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Computers, Materials and Continua 2024年第1期81卷 663-684页

作者： Cong, xin feng, Lanjin Zi, Lingling College of Computer and Information Science Chongqing Normal University Chongqing 401331 China

In the digital information age, distributed file storage technologies like the InterPlanetary File System (IPFS) have gained considerable traction as a means of storing and disseminating media content. Despite the advantages of decentralized storage, the proliferation of decentralized technologies has highlighted the need to address the issue of file ownership. The aim of this paper is to address the critical issues of source verification and digital copyright protection for IPFS image files. To this end, an innovative approach is proposed that integrates blockchain, digital signature, and blindwatermarking. Blockchain technology functions as a decentralized and tamper-resistant ledger, recording and verifying the source information of files, thereby establishing credible evidence of file origin. A digital signature serves to authenticate the identity and integrity of the individual responsible for uploading the file, ensuring data security. Furthermore, blind watermarking is employed to embed invisible information within images, thereby safeguarding digital copyrights and enabling file traceability. To further optimize the efficiency of file retrieval within IPFS, a dual-layerDistributedHash Table (DHT) indexing structure is proposed. This structure divides file index information into a global index layer and a local index layer, significantly reducing retrieval time and network overhead. The feasibility of the proposed approach is demonstrated through practical examples, providing an effective solution to the copyright protection issues associated with IPFS image files. © 2024 The Authors.

关键词： Blockchain

Hydrochemical characteristics and the ecological effect of algal carbonic anhydrase in carbon cycle in the Taiyuan section of Fenhe River

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Journal of Oceanology and Limnology 2024年第5期42卷 1507-1524页

作者： Jing YANG xin LI Shulian XIE Jia feng Shanxi Key Laboratory of Yuncheng Salt Lake Ecological Protection and Resource Utilization College of Life SciencesYuncheng UniversityYuncheng 044000China School of Life Science Shanxi UniversityTaiyuan 030006China

Water scarcity and pollution pose a threat to the sustainable development of cities and ***,it is crucial to analyze the hydrochemical characteristics and carbon dynamics of waterdeficient *** the Taiyuan section of Fenhe River as the research object,we systematically explored the hydrochemical characteristics of surface water and its evolutionary processes,as well as the ecological effect of algal carbonic anhydrase in carbon cycle using the hydrochemical evolution method and correlation *** ternary diagram demonstrates that the main water chemical type in Fenhe River was SO^(2-)_(4)·Cl^(-)-Na^(+).The Gibbs and end-member diagrams of each ion display that the chemical composition of surface water was mainly controlled by silicate *** chemical ions originated mainly from dissolution of some minerals,such as plagioclase,halite,dolomite,calcite,and *** diatoms had a lower CO_(2)requirement because they exhibited a higher abundance at a lower partial pressure of CO_(2)(p CO_(2)).However,high CO_(2)concentration had a positive effect on cyanobacteria,which reduced the active transport of HCO_(3)^(-),saved the energy needed for this part of active transport,and indirectly improved the overall photosynthetic efficiency of *** anhydrase(CA)activity was significantly negatively correlated with p CO_(2)and positively correlated with HCO_(3)^(-)concentration,indicating that CA in water promoted the conversion of CO_(2)to HCO_(3)^(-).The HCO_(3)^(-)generated from this process continued to participate in the erosion of silicate rocks,sequestering CO_(2)in the form of Ca CO_(3),which has a non-negligible impact on the carbon sink in the Fenhe *** consequences may have important implications for the biogeochemical cycling occurring in urban water.

关键词： hydrochemistry inorganic carbon phytoplankton community carbonic anhydrase Fenhe River

No more free lunch:The increasing popularity of machine learning and financial market efficiency

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Economic and Political Studies 2024年第1期12卷 34-57页

作者： Jian feng xin Liu Faculty of Business and Economics The University of Hong KongHong Kong SARChina School of Finance Renmin University of ChinaBeijingChina

In this paper,we show that the increasing popularity of machine learning improves market *** analysing the performance of a set of popular machine learning-based investment strategies,we find that profits from these strategies experience significant declines since the wide adoption of machine learning techniques,especially for profits based on the more preferred method of neural *** declines mainly come from long *** the‘machine learning’Google search index as a proxy for machine learning-based trading intensity,we find that returns from the neural networks-based long–short and long-only strategies are weaker following high levels of machine learning intensity,while no relation is found between machine learning intensity and the short-only neural networks-based strategy.

关键词： Machine learning market efficiency mispricing neural networks arbitraging activities

Left atrial area index predicts adverse cardiovascular events in patients with unstable angina pectoris

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Journal of Geriatric Cardiology 2016年第8期13卷 652-657页

作者： Yi-Fan LI Wei-Hong LI Zhao-Ping LI xin-heng feng Wei-Xian XU Shao-Min CHEN Wei GAO Department of Cardiology Peking University Third Hospital Beijing China Department of Pediatric Cardiology Guangdong Cardiovascular institute Guangdong General Hospital GuangzhouChina.

Background The left atrial size has been considered as a useful marker of adverse cardiovascular outcomes. However, it is not well known whether left atrial area index （LAAI） has predictive value for prognosis in patients with unstable angina pectoris （UAP）. This study was aimed to assess the association between LAAI and outcomes in UAP patients. Methods We enrolled a total of 391 in-hospital patients diag- nosed as UAP. Clinical and echocardiographic data at baseline were collected. The patients were followed for the development of ad- verse cardiovascular （CV） events, including hospital readmission for angina pectoris, acute myocardial infarction （AMI）, congestive heart failure （CHF）, stroke and all-cause mortality. Results During a mean follow-up time of 26.3±8.6 months, 98 adverse CV events occurred （84 hospital readmission for angina pectoris, four AMI, four CHF, one stroke and five all-cause mortality）. In a multivariate Cox model, LAAI [OR： 1.140, 95% CI： 1.01±1.279, P = 0.026], diastolic blood pressure （OR： 0.976, 95% CI： 0.956-0.996, P = 0.020） and pulse pressure （OR 1.020, 95% CI： 1.007-1.034, P = 0.004） were independent predictors for adverse CV events in UAP patients. Conclusions LAAI is a predictor of adverse CV events independent of clinical and other echocardiographic parameters in UAP patients.

关键词： Adverse cardiovascular events Left atrial area index Prognostic factor Unstable angina pectoris

Risk Factors of Depression Screened by Two-Sample Mendelian Randomization Analysis:A Systematic Review

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Biomedical and Environmental Sciences 2024年第1期37卷 85-95页

作者： WANG Han Lin XUE Yan feng CUI Bao Qiu LIU Hong SHEN xin xin Shandong Provincial Research Center for Bioinformatic Engineering and Technique School of Life SciencesShandong University of TechnologyZibo 255049ShandongChina Shanxi Province Cancer Hospital/Shanxi Hospital Affiliated to Cancer Hospital Chinese Academy of Medical Sciences/Cancer Hospital Affiliated to Shanxi Medical UniversityTaiyuan 030013ShanxiChina State Key Laboratory of Infectious Disease Prevention and Control National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China

Objective This study explored the potentially modifiable factors for depression and major depressive disorder(MDD)from the MR-Base database and further evaluated the associations between drug targets with *** We analyzed two-sample of Mendelian randomization(2SMR)using genetic variant depression(n=113,154)and MDD(n=208,811)from Genome-Wide Association Studies(GWAS).Separate calculations were performed with modifiable risk factors from MR-Base for 1,001 *** MR analysis was performed by screening drug targets with MDD in the DrugBank database to explore the therapeutic targets for *** variance weighted(IVW),fixed-effect inverse variance weighted(FE-IVW),MR-Egger,weighted median,and weighted mode were used for complementary *** The potential causal relationship between modifiable risk factors and depression contained 459 results for depression and 424 for ***,the associations between drug targets and MDD showed that SLC6A4,GRIN2A,GRIN2C,SCN10A,and IL1B expression are associated with an increased risk of *** contrast,ADRB1,CHRNA3,HTR3A,GSTP1,and GABRG2 genes are candidate protective factors against *** This study identified the risk factors causally associated with depression and MDD,and estimated 10 drug targets with significant impact on MDD,providing essential information for formulating strategies to prevent and treat depression.

关键词： Risk factors Drug targets Depression Major depressive disorder Two-sample Mendelian randomization