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Acute and chronic excitotoxicity in ischemic stroke and late-onset Alzheimer's disease

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neural Regeneration Research 2025年第7期20卷 1981-1988页

作者： Shan Ping Yu Emily Choi Michael qJiang Ling Wei Department of Anesthesiology Emory University School of MedicineAtlantaGAUSA Center for Visual and neurocognitive Rehabilitation Atlanta Veterans Affairs Medical CenterDecaturGAUSA

Stroke and Alzheimer's disease are common neurological disorders and often occur in the same *** comorbidity of the two neurological disorders represents a grave health threat to older *** review presents a brief background of the development of novel concepts and their clinical *** activity of glutamatergic n-methyl-D-aspartate receptors and n-methyl-D-aspartate receptor-mediated Ca^(2+)influx is critical for neuronal *** ischemic insult induces prompt and excessive glutamate release and drastic increases of intracellular Ca^(2+)mainly via n-methyl-D-aspartate receptors,particularly of those at the extrasynaptic *** Ca^(2+)-evoked neuronal cell death in the ischemic core is dominated by necrosis within a few hours and days known as acute ***,mild but sustained Ca^(2+)increases under neurodegenerative conditions such as in the distant penumbra of the ischemic brain and early stages of Alzheimer's disease are not immediately toxic,but gradually set off deteriorating Ca^(2+)-dependent signals and neuronal cell loss mostly because of activation of programmed cell death *** on the Ca^(2+)hypothesis of Alzheimer's disease and recent advances,this Ca^(2+)-activated“silent”degenerative excitotoxicity evolves from years to decades and is recognized as a unique slow and chronic *** n-methyl-D-aspartate receptor subunit Glun3A,primarily at the extrasynaptic site,serves as a gatekeeper for the n-methyl-D-aspartate receptor activity and is neuroprotective against both acute and chronic *** stroke and Alzheimer's disease,therefore,share an n-methyl-D-aspartate receptor-and Ca^(2+)-mediated mechanism,although with much different time *** is thus proposed that early interventions to control Ca^(2+)homeostasis at the preclinical stage are pivotal for individuals who are susceptible to sporadic late-onset Alzheimer's disease and Alzheimer's disease-related

关键词： Ca^(2+)hypothesis cognitive deficits hyperactivity late-onset Alzheimer's disease neurodegeneration n-methyl-D-aspartate receptors n-methyl-D-aspartate receptor subunits pathogenesis preventive treatment

Semi-clathrate hydrate based carbon dioxide capture and separation techniques

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Frontiers of Environmental Science & Engineering 2023年第12期17卷 1-29页

作者： Lijuan Gu hailong Lu Beijing International Center for Gas Hydrate School of Earth and Space SciencesPeking UniversityBeijing 100871China national Engineering Research Center for Gas Hydrate Exploration and Development Guangzhou 511466China

CO_(2)is considered as the main contributor to global warming,and hydrate enclathration is an efficient way for carbon capture and separation(CCS).Semi-clathrate hydrate(SCH)is a type of clathrate hydrate capable of encaging CO_(2)molecules under mild temperature and pressure *** has numerous unique advantages,including high thermal stability,selective absorption of gas molecules with proper size and recyclable,making it a promising candidate for *** SCH based CCS technology is in the developing stage and great efforts have to be conducted to improve the performance that is determined by their thermodynamical and structural *** review summarizes and compares the thermodynamic and structural properties of SCH and quaternary salt hydrates with gas mixtures to be captured and *** on the description of the physical properties of SCH and hydrate of quaternary salts with gas mixture,the CO_(2)capture and separation from fuel gas,flue gas and biogas with SCH are *** review focuses on the use of tetra-nbutyl ammonium halide and tetra-n-butyl phosphonium halide,which are the current application *** review aims to provide guidance for the future applications of SCH.

关键词： Semi-clathrate hydrate Tetra-n-butyl ammonium halide Tetra-n-butyl phosphonium halide Structure Thermodynamical properties CO_(2) capture and separation

Mixed-mode fast-slow oscillations in the frequency switching Duffing system with a 1:n frequency ratio

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Applied Mathematics and Mechanics(English Edition) 2024年第12期45卷 2131-2146页

作者： Shiping JIAnG Xiujing HAn hailong YU School of Physics Nanjing University of Science&TechnologyNanjing 210094China Faculty of Civil Engineering and Mechanics Jiangsu UniversityZhenjiang 212013Jiangsu ProvinceChina School of Energy and Power Engineering Nanjing University of Science&TechnologyNanjing 210094China

Sliding fast-slow oscillations are interesting oscillation patterns discovered recently in the Duffing system with frequency *** oscillations have been obtained with a fixed 1:2 low frequency ratio in the previous *** present paper aims to explore composite fast-slow dynamics when the frequency ratio is *** a result,a novel route to composite fast-slow dynamics is *** find that,when presented with variable frequency ratios in a 1:n fashion,the sliding fast-slow oscillations may turn into the ones characterized by the fact that the clusters of large-amplitude oscillations of relaxational type are exhibited in each period of the oscillations,and hence the mixedmode fast-slow *** on whether the transition of the trajectory is from the upper subsystem via the fold bifurcation or not,these interesting oscillations are divided into two classes,both of which are investigated *** study shows that,when the frequency ratio n is increased from n=3,newly created boundary equilibrium bifurcation points may appear on the original sliding boundary line,which is divided into smaller parts,showing sliding and downward crossing dynamical *** is the root cause of the clusters,showing large-amplitude oscillations of relaxational type,resulting in the formation of mixed-mode fast-slow ***,a novel route to composite fast-slow dynamics by frequency switching is ***,the effects of the forcing on the mixed-mode fast-slow oscillations are *** magnitude of the forcing frequency may have some effects on the number of large-amplitude oscillations in the *** magnitude of the forcing amplitude determines whether the fast-slow characteristics can be produced.

关键词： sliding fast-slow dynamics mixed-mode fast-slow oscillation fold bifurcation frequency switching Duffing system

Isothermal oxidation behavior of nb-bearing austenitic cast steels at 950℃

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International Journal of Minerals,Metallurgy and Materials 2022年第4期29卷 814-824页

作者： hailong Zhao Longfei Li qiang Feng Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China

The oxidation behaviors of three austenitic cast steels with different morphologies of primary carbides at 950℃ in air were investigated using scanning electron microscopy,energy dispersive spectroscopy,and focused ion beam/transmission electron *** oxidation kinetics followed a logarithmic law,and the oxidation rate can be significantly decreased as long as a continuous silica layer formed at the scale/substrate *** the local Si concentration was inadequate,internal oxidation occurred beneath the oxide *** spallation of oxides during cooling can be inhibited with the formation of internal oxidation,owing to the reduced mismatch stress between the oxide scale and the ***“Chinese-script”primary nb(C,n)was superior to the dispersed primary nb(C,n)in suppressing the oxidation penetration in the interdendritic region by supplying a high density of quick-diffusion Cr *** addition,the innermost and outermost oxidation layers were enriched with Cr,whereas the Cr evaporation in the outermost layer was significant when the water vapor concentration in the environment was high *** findings further the understanding regarding the oxidation behavior of austenitic cast steels and will promote the alloy development for exhaust components.

关键词： austenitic cast steels isothermal oxidation primary nb(C,n) internal oxidation Cr depletion

Eastern equatorial Pacific SST seasonal cycle in global climate models: from CMIP5 to CMIP6

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Acta Oceanologica Sinica 2020年第7期39卷 50-60页

作者： Zhenya Song hailong Liu Xingrong Chen First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China School of Oceanography Shanghai Jiaotong UniversityShanghai 200240China national Marine Environmental Forecasting Center Ministry of Natural ResourcesBeijing 100081China

The sea surface temperature(SST)seasonal cycle in the eastern equatorial Pacific(EEP)plays an important role in the El nino–Southern Oscillation(EnSO)***,the reasonable simulation of SST seasonal cycle in the EEP is still a challenge for climate *** this paper,we evaluated the performance of 17 CMIP6 climate models in simulating the seasonal cycle in the EEP and compared them with 43 CMIP5 climate *** general,only CESM2 and SAM0-UnICOn are able to successfully capture the annual mean SST characteristics,and the results showed that CMIP6 models have no fundamental improvement in the model annual mean *** the seasonal cycle,14 out of 17 climate models are able to represent the major characteristics of the observed SST annual *** spring,12 models capture the 1–2 months leading the eastern equatorial Pacific region 1(EP1;5°S–5°n,110°–85°W)against the eastern equatorial Pacific region 2(EP2;5°S–5°n,140°–110°W).In autumn,only two models,GISS-E2-G and SAM0-UnICOn,correctly show that the EP1 and EP2 SSTs vary in *** the CMIP6 MME SST simulation in EP1,both the cold bias along the equator in the warm phase and the warm bias in the cold phase lead to a weaker annual SST cycle in the CGCMs,which is similar to the CMIP5 ***,both the seasonal cold bias and warm bias are considerably decreased for CMIP6,which leads the annual SST cycle to more closely reflect the *** the CMIP6 MME SST simulation in EP2,the amplitude is similar to the observed value due to the quasi-constant cold bias throughout the year,although the cold bias is clearly improved after August compared with CMIP5 ***,although SAM0-UnICOn successfully captured the seasonal cycle characteristics in the EEP and the improvement from CMIP5 to CMIP6 in simulating EEP SST is clear,the fundamental climate models simulated biases still exist.

关键词： CMIP5 CMIP6 eastern equatorial Pacific SST seasonal cycle

Origins of Terrestrial Organic Matter in Surface Sediments of the East China Sea Shelf

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Journal of Ocean University of China 2017年第5期16卷 793-802页

作者： ZHAnG hailong XInG Lei ZHAO Meixun Key Laboratory of Marine Chemistry Theory and Technology(Ocean University of China) Ministry of Education/Qingdao Collaborative Innovation Center of Marine Science and TechnologyQingdao 266100P.R.China Institute of Marine Organic Geochemistry Ocean University of ChinaQingdao 266100P.R.China

Terrestrial organic matter(TOM) is an important component of marine sedimentary OM, and revealing the origins and transport mechanisms of TOM to the East China Sea(ECS) is important for understanding regional carbon cycle. A novel approach combining molecular proxies and compound-specific carbon isotopes is used to quantitatively constrain the origins and transport mechanisms of TOM in surface sediments from the ECS shelf. The content of terrestrial biomarkers of(C_(27)+C_(29)+C_(31)) n-alkanes(52 to 580 ng g^(-1)) revealed a seaward decreasing trend, the δ^(13)CTOC values(-20.6‰ to-22.7‰) were more negative near the coast, and the TMBR(terrestrial and marine biomarker ratio) values(0.06 to 0.40) also revealed a seaward decreasing trend. These proxies all indicated more TOM(up to 48%) deposition in the coastal areas. The Alkane Index, the ratio of C_(29)/(C_(29)+C_(31)) n-alkanes indicated a higher proportion of grass vegetation in the coastal area; While the δ13C values of C_(29) n-alkane(-_(29).3‰ to-33.8‰) indicated that terrestrial plant in the sediments of the ECS shelf were mainly derived from C_3 plants. Cluster analysis afforded detailed estimates of different-sourced TOM contributions and transport mechanisms. TOM in the Zhejiang-Fujian coastal area was mostly delivered by the Changjiang River, and characterized by higher %TOM(up to 48%), higher %C_3 plant OM(68%-85%) and higher grass plant OM(56%-61%); TOM in the mid-shelf area was mostly transported by aerosols, and characterized by low %TOM(less than 17%), slightly lower C_3 plant OM(56%-72%) and lower grass plant OM(49%-55%).

关键词： alkanes coastal terrestrial shelf sedimentary mostly aerosols vegetation quantitatively decreasing

Synthesis of new Squarains Used as Organic Electroluminescent Materials

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Chinese Chemical Letters 1997年第5期8卷 403-406页

作者： Liu, n Lu, ZY Xie, MG Jiang, q SICHUAn UnIV DEPT CHEMCHENGDU 610064PEOPLES R CHINA

Two types of eight kinds of new squarains were designed and synthesized. Their structures were elucidated by IR,nMR,MS and elementary analysis. Their luminescent properties were determined,which indicated that they ca... 详细信息

关键词： OC Cl

Synthesis and Properties of Layered Oxides LiCo_(1-x)ni_xO_2

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Journal of Materials Science & Technology 1997年第5期13卷 405-408页

作者： Lin, q Chen, n Ye, W Liu, RM Luo, JS GEn RES InST nOnFERROUS MET BEIJING 100088PEOPLES R CHINA

The mechanism of LiCo1－xnixO2(x=0, 0.5, 1) synthesis from carbonates or hydrates was studied by thermogravimetric analysis and X-ray diffraction to identify the medium and final products. The synthesis process from carbonates can be divided into two steps. Below 300℃cobalt carbonate and/or nickel carbonate decompose forming oxides. Over 300℃ Li2CO3 decomposes and reacts with Co and/or ni oxides gradually, as a result Co++ and/or ni++ areoxidized to Co+++ and/or ni+++, finally LiCo1-xnixO2 forms. The proportion of cobalt tonickel in the starting mixture and atmosphere during synthesis affects the structure of ***1-xnixO2(x≤0.5) can be synthesized in air or oxygen and characterized by solid solutionof LiCoO2 and LiniO2. LiniO2 can be obtained only from hydrates and in oxygen *** and LiCo0.5ni0.5O2 have higher first charge capacity than that of LiCoO2. Their discharge capacity reaches a level with that of LiCoO2 and has reasonable reversibility.

关键词： Lithium batteries

Magnetohydrodynamic flows tuning in a conduit with multiple channels under a magnetic field applied perpendicular to the plane of flow

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Journal of Hydrodynamics 2017年第2期29卷 332-343页

作者： Y.Luo C.n.Kim M.q.Zhu Department of Mechanical Engineering Graduate SchoolKyung Hee UniversityYong-inKorea Department of Mechanical Engineering College of EngineeringKyung Hee UniversityYong-inKorea

In this study, three-dimensional liquid-metal magnetohydrodynamic flows in a conduit with multiple channels under a uniform magnetic field are numerically investigated. The geometry of the conduit is of a four-parallel-channels system including one inflow channel and three outflow channels. The liquid-metal flows into the inflow channel, then turns through 180° in the transi- tion segment, finally flows into three different outflow channels. This kind of channel system can induce counter flow and co-flow, which is rarely investigated before though the conceptual designs of duct flow in the blanket have suggested this type of flow. A structured grid system is chosen after a series of mesh independence tests in the present study. The axial velocity in the side layer near the first partitioning wall, located between the inflow channel and the first outflow channel, is the highest with the lowest electric potential formed therein. The pressure almost linearly decreases in the main flow direction, except in the transition segment. Moreover, the pressure gradient in the first outflow channel is the largest among the three outflow channels. The interdependency of the current, fluid velocity, pressure, electric potential is examined in order to describe the electromagnetic characteristics of the liquid-metal flows.

关键词： Liquid-metal magnetohydrodynamics multiple channels