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Intrinsically asymmetric atomic character regulates piezoelectricity in two-dimensional materials

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Frontiers of physics 2024年第3期19卷 153-162页

作者： yun-qin Li Qi-Wen He dai-Song Tang Xiao Shang Xiao-Chun Wang School of Physics Science and Information Technology Liaocheng UniversityLiaocheng 252000China Key Laboratory of Polar Materials and Devices Ministry of EducationDepartment of ElectronicsEast China Normal UniversityShanghai 200241China Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China

Decreasing of layer thickness causes the decrease of polarization until it disappears due to the existence of depolarization ***,the search for strong piezoelectric materials is highly desirable for multifunctional ultra-thin piezoelectric ***,we propose a common strategy for achieving strong piezoelectric materials through the electronic asymmetry induced by the intrinsically asymmetric atomic character of different chalcogen ***,in the tetrahedral lattice structures,for example,M4X3Y3(M=Pd/Ni,X/Y=S,Se or Te,X≠Y)monolayers are proved to display excellent out-of-plane ***4Se3Te3 possesses the largest piezoelectric coefficient d33 of 61.57 pm/V,which is much larger than that of most 2D *** the electronic asymmetry further increases the out-of-plane piezoelectricity of Janus M4X3Y3 ***,the out-of-plane piezoelectricity is positively correlated with the ratio of electronegativity difference(Red)and the electric dipole moment(P).This work provides alternative materials for energy harvesting nano-devices or self-energized wearable devices,and supplies a valuable guideline for predicting 2D materials with strong out-of-plane piezoelectricity.

关键词： piezoelectricity intrinsically asymmetric atomic character ratio of electronegativity difference electric dipole moment first-principles calculations

Effect of the vortical structures on the hydrodynamic performance of a pitching hydrofoil

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Journal of Hydrodynamics 2024年第2期36卷 406-420页

作者： Rui Yuan Hui-yun Hao qin Wu yun-qing Liu Biao Huang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China

The objective is to study the vortical structural behaviors of a transient pitching hydrofoil and their effects on the hydrodynamic performance. The pitching motion of the hydrofoil is set to pitch up with an almost constant rate from 5° to 15° and then back to 5°, with the Reynolds number 4.4×10^(5) and the frequency 2 Hz. The results show that the main coherent structures around the pitching hydrofoil include small-scale laminar separation bubble (LSB), large-scale second vortex (SV) and trailing edge vortex (TEV) which are all vortical. The relationship between the vortical structure and the lift is investigated with the finite-domain impulse theory. It indicates that the major part of the lift is contributed by the LSB, whereas the shedding and the formation of the SV and TEV cause the fluctuation of the lift. The proper orthogonal decomposition (POD) method is applied to capture the most energetic modes, revealing that the LSB mode occupies a large amount of energy in the flow field. The dynamic mode decomposition (DMD) method accurately extracts the dominant frequency and modal characteristics, with the first mode corresponding to the mean flow, the second mode corresponding to the LSB structure and the third and fourth modes corresponding to the vortex shedding.

关键词： Hydrodynamics vortical structures finite-domain impulse theory proper orthogonal decomposition(POD) dynamic mode decomposition(DMD) Pitching hydrofoil

Effect of streamlined nose length on aerodynamic performance of high-speed train with a speed of 400 km/h

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第7期25卷 525-540页

作者： Nianxun LI Tian LI Zhiyuan dai Deng qin Jiye ZHANG State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu 610031China

The streamlined nose length(SNL)plays a crucial role in determining the aerodynamic performance of high-speed *** appropriate SNL can not only effectively reduce the magnitude of aerodynamic drag and lift forces,but also improve the performance of the high-speed train in tunnel passing and crosswind *** this study,a numerical simulation of the aerodynamic performance of high-speed trains at a speed of 400 km/h,with varying SNLs,is conducted using the k-ωshear stress transport(SST)turbulence *** different SNLs include 6.0,7.0,8.0,9.0,9.8,12.0,15.0,and 18.0 *** order to validate the accuracy of the numerical simulation,its results are compared with wind tunnel test data obtained from the *** simulation is carried out using compressible and incompressible gases to determine the effect of gas compressibility on *** impact of SNL on the aerodynamic performance of the trains is analyzed in terms of aerodynamic forces,velocity,and pressure *** comparison to the original train,the train with a 6.0 m SNL experienced a 10.8%increase in overall aerodynamic ***,the lift forces on the head and tail cars increased by 35.7%and 75.5%,*** the other hand,the train with an 18.0 m SNL exhibited a 16.5%decrease in aerodynamic ***,the lift forces on the head and tail cars decreased by 21.9%and 49.7%,*** aerodynamic drag force of the entire train varies linearly with the SNL,while the aerodynamic lift of the tail car follows a quadratic function in relation to the SNL.

关键词： Streamlined nose length(SNL) High-speed train Aerodynamic performance Numerical simulation Flow structures

Effect of liquid surface depression size on discharge characteristics and chemical distribution in the plasma-liquid anode system

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Plasma Science and Technology 2024年第9期26卷 17-31页

作者： yun LING Dong dai Jiaxin CHANG Buang WANG School of Electric Power South China University of TechnologyGuangzhou 510641People’s Republic of China University of Richmond Richmond 23173United States of America

Atmospheric pressure plasma-liquid interactions exist in a variety of applications,including wastewater treatment,wound sterilization,and *** practice,the phenomenon of liquid surface depression will inevitably *** applied gas will cause a depression on the liquid surface,which will undoubtedly affect the plasma generation and further affect the application ***,the effect of liquid surface deformation on the plasma is still *** this work,numerical models are developed to reveal the mechanism of liquid surface depressions affecting plasma discharge characteristics and the consequential distribution of plasma species,and further study the influence of liquid surface depressions of different sizes generated by different helium flow rates on the *** show that the liquid surface deformation changes the initial spatial electric field,resulting in the rearrangement of electrons on the liquid *** charges deposited on the liquid surface further increase the degree of distortion of the electric ***,the electric field and electron distribution affected by the liquid surface depression significantly influence the generation and distribution of active species,which determines the practical effectiveness of the relevant *** work explores the phenomenon of liquid surface depression,which has been neglected in previous related work,and contributes to further understanding of plasma-liquid interactions,providing better theoretical guidance for related applications and technologies.

关键词： plasma-liquid interaction deformation of the liquid surface liquid anode species fluxes

Current Immunotherapy Strategies for Rheumatoid Arthritis:The Immunoengineering and Delivery Systems

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Research 2024年第3期2023卷 169-189页

作者： Chenyu Zhang Peixiang Ma An qin Liao Wang Kerong dai Yuanyuan Liu Jie Zhao Zuyan Lu School of Medicine Shanghai UniversityShanghaiChina Clinical and Translational Research Center for 3D Printing Technology Shanghai Ninth People's HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Shanghai Key Laboratory of Orthopedic Implants Department of Orthopedic SurgeryShanghai Ninth People's HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Shanghai Frontiers Science Center of Degeneration and Regeneration in Skeletal System ShanghaiChina.

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease accompanied by persistent multiarticular synovitis and cartilage degradation. The present clinical treatments are limited to disease-modifying anti-rheumatic drugs (DMARDs) and aims to relieve pain and control the inflammation of RA. Despite considerable advances in the research of RA, the employment of current clinical procedure is enormous, hindered by systemic side effect, frequent administration, tolerance from long-lasting administration, and high costs. Emerging immunoengineering-based strategies, such as multiple immune-active nanotechnologies via mechanism-based immunology approaches, have been developed to improve specific targeting and to reduce adverse reactions for RA treatments. Here, we review recent studies in immunoengineering for the treatment of RA. The prospect of future immunoengineering treatment for RA has also been discussed.

关键词： drugs Rheumatoid treatment

Consensus on glycemic management for patients with coronary heart disease and type 2 diabetes

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Journal of Geriatric Cardiology 2024年第7期21卷 689-702页

作者： Li-Nong JI yun-dai CHEN Jing LIU Xiang-Hai ZHOU Cardiovascular Subcommittee of Chinese International Exchange and Promotion Association for Medical and Healthcare Peking University People's Hospital Chinese PLA General Hospital

The prevalence of patients with coronary heart disease(CHD)and diabetes mellitus is notably high,posing sig-nificant residual cardiovascular risks even after routine interventions such as antihypertensive,lipid-lowering,and antithrombot-ic *** studies have demonstrated that certain glucose-lowering medications confer cardiovascular benefits for pa-tients with type 2 ***,a survey indicates that cardiologists may not be fully acquainted with the optimal screen-ing timing,indicators,and diagnostic criteria for type 2 diabetes,and there is insufficient awareness and a low rate of prescrip-tion of novel glucose-lowering medications with proven cardiovascular efficacy,such as glucagon-like peptide-1 receptor agon-ists(GLP-1 RAs)and sodium-glucose co-transporter-2 inhibitors(SGLT-2i).In this context,based on domestic and international guidelines or consensus and the latest evidence-based evidence,this consensus aims to standardize the glycemic management for patients with acute coronary syndrome,chronic coronary syndrome,and perioperative management for percutaneous coronary *** highlights the key points of screening and diagnosis of type 2 diabetes,and the comprehensive management of cardiovascular risk in patients with *** consensus elaborates on the principles and algorithms of glycemic management for CHD patients,without involving acute complications of diabetes,clarifies the clinical practice of glucose-lowering medications with cardiovascular benefits,and promotes the standardized use of these medications in cardiovascular and other related spe-cialty ***,it addresses the glucose-lowering treatment to comprehensively reduce cardiovascular risks.

关键词： coronary patients routine

Human immunodeficiency virus-associated dementia complex with positive 14-3-3 protein in cerebrospinal fluid:A case report

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World Journal of Clinical Cases 2024年第12期12卷 2065-2073页

作者： yun-Sen He Xiao-Hong qin Min Feng qin-Jiang Huang Meng-Jun Zhang Li-Li Guo Ming-Bin Bao Ye Tao Hong-Yuan dai Bo Wu Department of Neurosurgery Sichuan Lansheng Brain Hospital&Shanghai Lansheng Brain Hospital Investment Co.Ltd.Chengdu 610036Sichuan ProvinceChina Department of Psychiatry Sichuan Provincial Center for Mental HealthChengdu 610072Sichuan ProvinceChina Department of Geriatrics Municipal People’s Hospital in LuzhouLuzhou 646000Sichuan ProvinceChina Department of Neurosurgery Wenjiang District People’s Hospital of ChengduChengdu 611100Sichuan ProvinceChina Department of Neurosurgery Sichuan Provincial People's HospitalUniversity of Electronic Science and Technology of China ChengduChengdu 610072Sichuan ProvinceChina Department of Neurology Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610072Sichuan ProvinceChina

BACKGROUND Human immunodeficiency virus(HIV)-associated dementia(HAD)is a subcortical form of dementia characterized by memory deficits and psychomotor ***,HAD often presents with symptoms similar to those of Creutzfeldt-Jakob disease(CJD),particularly in patients with acquired immune deficiency syndrome(AIDS).CASE SUMMARY We report the case of a 54-year-old male who exhibited cognitive dysfunction and secondary behavioral changes following HIV infection and suspected prion *** patient was diagnosed with HIV during hospitalization and his cerebrospinal fluid tested positive for 14-3-3 *** electroencephalogram showed a borderline-abnormal periodic triphasic wave ***-enhanced magnetic resonance imaging revealed moderate encephalatrophy and ***,symptomatic treatment and administration of amantadine were pursued for presumed CJD,but the patient’s condition continued to *** contrast,the patient’s condition improved following anti-HIV *** individual is also the only patient with this prognosis to have survived over 4 ***,the diagnosis was revised to *** In the diagnostic process of rapidly progressive dementia,it is crucial to rule out as many potential causes as possible and to consider an autopsy to diminish diagnostic *** 14-3-3 protein should not be regarded as the definitive marker for *** laboratory screening for infectious diseases is essential to enhance diagnostic precision,especially in AIDS patients with potential ***,a trial of diagnostic treatment may be considered when additional testing is not feasible.

关键词： HIV-associated dementia Cognitive dysfunction Creutzfeld-Jakob disease Rapidly progressive dementia Case report

Covalently Bonded Ni Sites in Black Phosphorene with Electron Redistribution for Efficient Metal‑Lightweighted Water Electrolysis

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Nano-Micro Letters 2024年第6期16卷 233-245页

作者： Wenfang Zhai Ya Chen Yaoda Liu Yuanyuan Ma Paranthaman Vijayakumar Yuanbin qin Yongquan Qu Zhengfei dai State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049People’s Republic of China School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710072People’s Republic of China SSN Research Centre SSN College of EngineeringChennaiTamil Nadu 603110India

The metal-lightweighted electrocatalysts for water splitting are highly desired for sustainable and economic hydrogen energy deployments,but *** this work,a low-content Ni-functionalized approach triggers the high capability of black phosphorene(BP)with hydrogen and oxygen evolution reaction(HER/OER)*** a facile in situ electro-exfoliation route,the ionized Ni sites are covalently functionalized in BP nanosheets with electron redistribution and controllable metal *** is found that the as-fabricated Ni-BP electrocatalysts can drive the water splitting with much enhanced HER and OER *** 1.0 M KOH electrolyte,the optimized 1.5 wt%Nifunctionalized BP nanosheets have readily achieved low overpotentials of 136 mV for HER and 230 mV for OER at 10 mA cm^(−2).Moreover,the covalently bonding between Ni and P has also strengthened the catalytic stability of the Ni-functionalized BP electrocatalyst,stably delivering the overall water splitting for 50 h at 20 mA cm^(−2).Theoretical calculations have revealed that Ni–P covalent binding can regulate the electronic structure and optimize the reaction energy barrier to improve the catalytic activity *** work confirms that Ni-functionalized BP is a suitable candidate for electrocatalytic overall water splitting,and provides effective strategies for constructing metal-lightweighted economic electrocatalysts.

关键词： Black phosphorus Water electrolysis Electrocatalyst Electron redistribution Covalent functionalization

Global and regional soil organic carbon estimates:Magnitudes and uncertainties

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Pedosphere 2024年第4期34卷 685-698页

作者： Ziqi LIN Yongjiu dai Umakant MISHRA Guocheng WANG Wei SHANGGUAN Wen ZHANG Zhangcai qin School of Atmospheric Sciences Guangdong Province Key Laboratory for Climate Change and Natural Disaster StudiesSun Yat-sen UniversityZhuhai 519082China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China Computational Biology&Biophysics Sandia National LaboratoriesLivermore CA 94550USA Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Globally,soil is the largest terrestrial carbon(C)*** quantification of soil organic C(SOC)stocks in existing global observation-based estimates avails accurate predictions in carbon-climate feedbacks and future climate *** investigated the magnitudes and distributions of global and regional SOC estimates(i.e.,density and stocks)based on five widely used global gridded SOC datasets,a regional permafrost dataset developed in 2021(UM2021),and a global-scale soil profile database(World Soil Information Service)reporting measurements of a series of physical and chemical edaphic *** five global gridded SOC datasets were the Harmonized World Soil Database(HWSD),World Inventory of Soil Emission Potentials at 30 arc-second resolution(WISE30sec),Global Soil Dataset for Earth System Models(GSDE),Global Gridded Soil Information at 250-m resolution(SoilGrids250m),and Global Soil Organic Carbon Map(GSOCmap).Our analyses showed that the magnitude and distribution of SOC varied widely among datasets,with certain datasets showing region-specific *** the global scale,SOC stocks at the top 30 and 100 cm were estimated to be 828(range:577–1171)and 1873(range:1086–2678)Pg C,*** estimates from GSDE,GSOCmap,and WISE30sec were comparable,and those of SoilGrids250m and HWSD were at the upper and lower *** spatial SOC distribution varied greatly among datasets,especially in the northern circumpolar and Tibetan Plateau permafrost ***,UM2021 and WISE30sec performed well in the northern circumpolar permafrost regions,and GSDE performed well in *** estimates of SOC by different datasets also showed large variabilities across different soil layers and *** discrepancies were generally smaller for the 0–30 cm soil than the 0–100 cm *** datasets demonstrated relatively higher agreement in grasslands,croplands,and shrublands/savannas than in other biomes(e.g.,wetlands).The users should be mindful of the gaps b

关键词： biome carbon cycle Earth System Models permafrost region soil dataset soil map