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Journal of Iron and Steel Research International 2024年第2期31卷 501-518页

作者： Bao-sheng Liu Peng-fei Xu Shao-hua Zhang Yan-rui Li Li-ming Mou Jia-li Li Yue-zhong Zhang Pei-mao Fu Fa-cai Shi College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024ShanxiChina College of Chemical and Biological Engineering Taiyuan University of Science and TechnologyTaiyuan030024ShanxiChina Technical Center Taiyuan Iron and Steel(Group)Co.Ltd.Taiyuan030003ShanxiChina

The corrosion mechanism of 510L low alloy steel treated by acid-cleaned surface(ACS)and eco-pickled surface(EPS)techniques in three simulated solutions(S0:atmospheric environment;S1:soil environment;S2:industrial environment)and the influence of interaction between different corrosive anions on corrosion were *** results show that the total corrosion rates of samples in three simulated solutions were in order of S2>S0>S1,which is simultaneously correlated with initial corrosion dissolution processes as well as after the formation of corrosion ***3−will inhibit the initial corrosion owing to the formation of films,whereas HSO3−will accelerate the dissolutions of the matrix based on the synergistic action of HSO3−and Cl−.On the other hand,there is no significant difference in corrosion rates between the samples treated by ACS and EPS *** EPS technique that is safe,reusable and environmentally friendly can be further widely used in future work.

关键词： Corrosion mechanism Low alloy steel Simulated solution Surface technique Immersion time

Frequency Domain Fatigue Evaluation on SCR Girth-Weld Based on Structural Stress

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China Ocean Engineering 2024年第2期38卷 255-270页

作者： ZHANG long ZHAO Tian-feng College of Safety and Ocean Engineering China University of Petroleum(Beijing)Beijing 102249China

The Steel Catenary Riser(SCR)is a vital component for transporting oil and gas from the seabed to the floating *** harsh environmental conditions and complex platform motion make the SCR’s girth-weld prone to fatigue *** structural stress fatigue theory and Master S-N curve method provide accurate predictions for the fatigue damage on the welded joints,which demonstrate significant potential and compatibility in multi-axial and random fatigue ***,we propose a new frequency fatigue model subjected to welded joints of SCR under multiaxial stress,which fully integrates the mesh-insensitive structural stress and frequency domain random process and transforms the conventional welding fatigue technique of SCR into a spectrum analysis technique utilizing structural ***,a full-scale FE model of SCR with welds is established to obtain the modal structural stress of the girth weld and the frequency response function(FRF)of modal coordinate,and a biaxial fatigue evaluation about the girth weld of the SCR can be achieved by taking the effects of multi-load correlation and pipe-soil interaction into *** research results indicate that the frequency-domain fatigue results are aligned with the time-domain results,meeting the fatigue evaluation requirements of the SCR.

关键词： SCR girth weld random vibration self(cross)power spectrum structural stress method biaxial fatigue damage

Epidemiology and current management of cerebrovascular disease in China

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Journal of Geriatric Cardiology 2024年第5期21卷 465-474页

作者： sheng-Shou HU The Writing Committee of the Report on Cardiovascular Health and Diseases in China

The Annual Report on Cardiovascular Health and Diseases in China(2022)intricate landscape of cardiovascular health in *** connection with the previous section,this fifth section of the report continues the dissection on the manage-ment of cardiovascular diseases(CVD).Cerebrovascular disease is the leading cause of death and loss of healthy life among Chinese *** on the results of GBD 2019,from 1990 to 2019,the years of life lost due to premature death caused by stroke showed a decreasing trend,while the years lived with disability still increased *** present,national mortal-ity surveillance system can provide national and provincial representative annual death data on cerebrovascular disease,but the national representative data on some other important epidemiological indicators(such as incidence,prevalence,disability rate,and case fatality rate)are scarce in *** the construction of large cohort population and extension of follow-up time,re-search on stroke-related risk factors is increasing,providing a basis for the prevention and control of risk *** to limited large-scale population-based intervention studies,there is a lack of epidemiological evidence to transform into feasible interven-tion strategies and *** recent years,great progress in endovascular treatment for basilar-artery occlusion has been achieved in China,but there is still much room for improvement of guideline-based anticoagulant treatment and lipid-lowering treatment,as well as standardized diagnosis and treatment among patients with ischemic stroke.

关键词： prevention diagnosis Epidemiology

Designing Proportional-Integral Consensus Protocols for Second-Order Multi-Agent Systems Using Delayed and Memorized State Information

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 878-892页

作者： Honghai Wang Qing-long Han the College of Information Science and Engineering State Key Laboratory of Synthetical Automation for Process IndustriesNortheastern UniversityShenyang 110819China the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourneVIC 3122Australia

This paper is concerned with consensus of a secondorder linear time-invariant multi-agent system in the situation that there exists a communication delay among the agents in the network.A proportional-integral consensus protocol is designed by using delayed and memorized state *** the proportional-integral consensus protocol,the consensus problem of the multi-agent system is transformed into the problem of asymptotic stability of the corresponding linear time-invariant time-delay *** that the location of the eigenvalues of the corresponding characteristic function of the linear time-invariant time-delay system not only determines the stability of the system,but also plays a critical role in the dynamic performance of the *** this paper,based on recent results on the distribution of roots of quasi-polynomials,several necessary conditions for Hurwitz stability for a class of quasi-polynomials are first *** allowable regions of consensus protocol parameters are *** necessary and sufficient conditions for determining effective protocol parameters are *** designed protocol can achieve consensus and improve the dynamic performance of the second-order multi-agent ***,the effects of delays on consensus of systems of harmonic oscillators/double integrators under proportional-integral consensus protocols are ***,some results on proportional-integral consensus are derived for a class of high-order linear time-invariant multi-agent systems.

关键词： Consensus protocol Hurwitz stability multi-agent systems quasi-polynomials time delay

Performance and enhanced oil recovery efficiency of an acid-resistant polymer microspheres of anti-CO2 channeling in low-permeability reservoirs

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Petroleum Science 2024年第4期21卷 2420-2432页

作者： Hai-Zhuang Jiang Hong-Bin Yang Ruo-sheng Pan Zhen-Yu Ren Wan-Li Kang Jun-Yi Zhang Shi-long Pan Bauyrzhan Sarsenbekuly State Key Laboratory of Deep Oil and Gas China University of Petroleum (East China) School of Petroleum Engineering China University of Petroleum (East China) Oil and Gas Engineering Research Institute School of Energy and Petroleum Industry Kazakh-British Technical University

CO2flooding is a vital development method for enhanced oil recovery in low-permeability reservoirs,However,micro-fractures are developed in low-permeability reservoirs,which are essential oil flow channels but can also cause severe CO2gas channeling ***,anti-gas channeling is a necessary measure to improve the effect of *** kind of anti-gas channeling refers to the plugging of fractures in the deep formation to prevent CO2gas channeling,which is different from the wellbore *** microspheres have the characteristics of controllable deep plugging,which can achieve the profile control of low-permeability fractured *** acidic environments with supercritical CO2,traditional polymer microspheres have poor expandability and plugging *** on previous work,a systematic evaluation of the expansion performance,dispersion rheological properties,stability,deep migration,anti-CO2channeling and enhanced oil recovery ability of a novel acid-resistant polymer microsphere（DCNPM-A） was carried out under CQ oilifield conditions（salinity of85,000 mg/L,80℃,pH=3）.The results show that the DCNPM-A microsphere had a better expansion performance than the traditional microsphere,with a swelling rate of *** microsphere dispersion with a concentration of 0.1%-0.5% had the advantages of low viscosity,high dispersion and good injectability in the low permeability fractured *** the acidic environment of supercritical CO2,DCNPM-A microspheres showed excellent stability and could maintain strength for over 60 d with less *** core experiments,DCNPM-A microspheres exhibited delayed swelling characteristics and could effectively plug deep *** a plugging rate of 95%,the subsequent enhanced oil recovery of CO2flooding could reach 21.03%.The experimental results can provide a theoretical basis for anti-CO2channeling and enhanced oil recovery in low-permeability fractured reservoirs.

关键词： Low-permeability reservoir Anti-CO 2 channeling Polymer microsphere Acid resistance

On the half-quantized Hall conductance of massive surface electrons in magnetic topological insulator films

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 127-136页

作者： rui Chen Shun-Qing Shen Department of Physics The University of Hong KongHong Kong 999077China Department of Physics Hubei UniversityWuhan 430062China

In topological insulators,massive surface states resulting from local symmetry breaking were thought to exhibit a half-quantized Hall conductance,obtained from the low-energy effective model in an infinite Brillouin *** a lattice model,the surface band is composed of a combination of surface states and bulk *** massive surface states alone may not be enough to support an exact one-half quantized surface Hall conductance in a finite Brillouin zone and the whole surface band always gives an integer quantized Hall conductance as enforced by the TKNN *** explore this,we investigate the band structures of a lattice model describing the magnetic topological insulator film that supports the axion insulator,Chern insulator,and semi-magnetic topological insulator *** reveal that the gapped and gapless surface bands in the three phases are characterized by an integer-quantized Hall conductance and a half-quantized Hall conductance,*** propose an effective model to describe the three phases and show that the low-energy dispersion of the surface bands inherits from the surface Dirac *** gapped surface band manifests a nearly half-quantized Hall conductance at low energy near the center of Brillouin zone,but is compensated by another nearly half-quantized Hall conductance at high energy near the boundary of Brillouin zone because a single band can only have an integer-quantized Hall *** gapless band hosts a zero Hall conductance at low energy but is compensated by another half-quantized Hall conductance at high energy,and thus the half-quantized Hall conductance can only originate from the gapless ***,we calculate the layer-resolved Hall conductance of the *** conclusion suggests that the individual gapped surface band alone does not support the half-quantized surface Hall effect in a lattice model.

关键词： magnetic topological insulator Dirac equation half-quantized Hall conductance

Functional decoration on a regenerable bifunctional porous covalent organic framework probe for rapid detection and adsorption of copper ions

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Rare Metals 2024年第2期43卷 758-769页

作者： Yu-long Li Xi-Lang Jin Yi-Ting Ma Jing-rui Liu Fazal Raziq Peng-Yuan Zhu Zhi-Feng Deng Hong-Wei Zhou Wei-Xing Chen Wen-Huan Huang School of Materials and Chemical Engineering Xi’an Technological UniversityXi’an710021China Yulin Boyi-Jingking Research Institute of Industrial Technology Development Research Yulin719054China KAUST Catalysis Center King Abdullah University of Science and Technology23955-6900ThuwalKingdom of Saudi Arabia Key Laboratory of Chemical Additives for China National Light Industry College of Chemistry and Chemical EngineeringShaanxi University of Science and TechnologyXi’an710021China National and Local Joint Engineering Laboratory for Slag Comprehensive Utilization and Environmental Technology School of Materials Science and EngineeringShaanxi University of TechnologyHanzhong723001China

Developing fluorescence porous probe for detecting and eliminating Cu^(2+) contamination in water or biosystem is an essential research project that has attracted considerable ***,improving the fluorescence detecting efficiency while enhancing the adsorption capacity of the porous probe is of great ***,a bifunctional two-dimensional imine-based porous covalent organic framework(TTP-COF)probe was designed and synthesized from 1,3,5-tris(4-aminophenyl)benzene(TAPB)and 2,4,6-Triformylphloroglucinol(TP)***-COF displayed rapid detection of Cu^(2+)(limit of detection(LOD)=10 nmol·L^(−1) while achieving a high adsorption capacity of 214 mg·g^(−1)(pH=6)at room temperature with high reusability(>5 cycles).The key roles and contributions of highπ-conjugate and delocalized electrons in TABP and functional–OH groups in TP were *** importantly,the fluorescence quenching mechanism of TTP-COF was studied by density functional theory theoretical calculations,revealing the crucial role of intramolecular hydrogen bonds among C=N and–OH groups and the blocking of the excited state intramolecular proton transfer process in detecting process of Cu^(2+).

关键词： Covalent organic framework(COF) Excited-state intramolecular proton transfer(ESIPT) Copper ion detection Copper ion adsorption Renewability

Chinese herbal medicine decreases incidence of hepatocellular carcinoma in diabetes mellitus patients with regular insulin management

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 716-731页

作者： Hsiang-Chun Lai Ju-Chien Cheng Hei-Tung Yip long-Bin Jeng sheng-Teng Huang Graduate Institute of Chinese Medicine School of Chinese MedicineCollege of Chinese MedicineChina Medical UniversityTaichung 404328TaiwanChina Department of Medical Laboratory Science and Biotechnology China Medical UniversityTaichung 404TaiwanChina Management Office for Health Data China Medical University HospitalTaichung 404327TaiwanChina Organ Transplantation Center China Medical University HospitalTaichung 40447TaiwanChina Department of Chinese Medicine China Medical University HospitalSchool of Chinese MedicineChina Medical UniversityTaichung 40447TaiwanChina

BACKGROUND Type 2 diabetes mellitus(DM)is an independent risk factor for hepatocellular carcinoma(HCC),while insulin is a potent *** a new therapeutic modality for preventing insulin users from developing HCC is a critical goal for *** To investigate whether regular herbal medicine use can decrease HCC risk in DM patients with regular insulin *** We used data acquired from the Taiwan,Chinaese National Health Insurance research database between 2000 and *** identified patients with DM who were prescribed insulin for>3 *** herb user group was further defined as patients prescribed herbal medication for DM for>3 months per annum during RESULTS We initially enrolled 657144 DM patients with regular insulin use from 2000 to *** these,46849 patients had used a herbal treatment for DM,and 140547 patients were included as the matched control *** baseline variables were similar between the herb users and *** patients with regular herb use had a 12%decreased risk of HCC compared with the control group[adjusted hazard ratio(aHR)=0.88,95%CI=0.80–0.97].The cumulative incidence of HCC in the herb users was significantly lower than that of the *** with a herb use of>5 years cumulatively exhibited a protective effect against development of HCC(aHR=0.82,Plonger survival time than nonusers(aHR=0.78,P=0.0001).Additionally,we report the top 10 herbs and formulas in prescriptions and summarize the potential pharmacological effects of the *** analysis indicated that Astragalus propinquus(Huang Qi)plus Salvia miltiorrhiza Bunge(Dan Shen),and Astragalus propinquus(Huang Qi)plus Trichosanthes kirilowii Maxim.(Tian Hua Fen)were the most frequent combination of single ***,Ji sheng Shen Qi Wan plus Dan Shen was the most frequent combination of herbs and *** This large-scale retrospective cohort study reveals th

关键词： Hepatocellular carcinoma Diabetes mellitus Insulin Herb Taiwan,Chinaese National health insurance research database

Feedback processing in the primate brain and in AI systems

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Science China(Technological Sciences) 2024年第8期67卷 2297-2309页

作者： JIANG Yong HE sheng Institute of Biophysics Chinese Academy of SciencesBeijing 100101China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China University of Chinese Academy of Sciences Beijing 100049China

The primate brain and artificial intelligence(AI) can both be conceptualized as information processing systems, each with its own distinct biological and computational architectures. While there are parallels between them, their respective structural and functional connections show significant differences. In this paper, we examine the central role of feedback processing in both the primate brain and AI systems, which has been shown to be crucial in shaping neural processing. By reviewing the key features of feedback processes in the primate brain, which allows the brain to incorporate prior knowledge, contextual information, and taskdemands into early-stage processing, we highlight the divergence in goals and functions between biological and AI *** these differences is crucial for elucidating the cognitive capabilities of the primate brain and for addressing computational challenges in AI. In advocating “Cognition-Inspired-Computation”, we suggest that integrating insights from feedback processing in the primate brain into AI research will offer potentially significant improvements for the advancement of AI systems.

关键词： cognitive neuroscience artificial intelligence feedback processing attention learning

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Modified constitutive models for Inconel 718 considering current density and temperature in electrically assisted forming process

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Chinese Journal of Aeronautics 2024年第2期37卷 524-540页

作者： Xuan CUI rui ZHAO Min WAN School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Jiangxi 330000China

Electrically Assisted Forming(EAF)technology has obvious advantages in material *** develop an effective constitutive model considering electrical effects,room temperature and electrically assisted quasi-static uniaxial tensile tests were conducted using ultrathin nickelbased superalloy plates with a thickness of 0.25 *** research focused on the two most widely recognized effects:the Joule thermal and the electric athermal *** mechanism of current action can be divided into two scenarios:one considering the Joule thermal effect only,and the other considering both effects *** basic constitutive models,namely the Modified-Hollomon model and the Johnson-Cook(J-C)model,were selected to be optimized through the classification of two different situations,and four optimized constitutive models were *** was found that the J-C model with simultaneous consideration of the Joule thermal effect and electric athermal effect had the best prediction effect by comparing the results of these four ***,the accuracy of the optimization model was verified by finite element simulation of the electrically assisted stretching optimization *** results show that the constitutive model can effectively predict the temperature effect caused by the Joule heat effect and the athermal effect of current on the material.

关键词： Joule heating Elastoplasticity Plastic deformation Superalloys Constitutive models