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Macrobioerosion and Microbioerosion in Marine Molluscan Shells from Holocene and Modern Beaches (39°-40°S, South of Buenos Aires Province, Argentina) 被引量:1
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作者 Melisa P. CHARO Jose L. CAVALLOTTO Guillermo ACENOLAZA 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第4期1215-1230,共16页
The marine sediments of the area of Verde Peninsula - Jabali Island (39°28'S/62°19%V-40°28' S/62°11'W) Holocene in age (3-2 ky), and modern beaches contain a significant amount of bioeroded ... The marine sediments of the area of Verde Peninsula - Jabali Island (39°28'S/62°19%V-40°28' S/62°11'W) Holocene in age (3-2 ky), and modern beaches contain a significant amount of bioeroded mollusc shells. Fifteen sites were analyzed, in which 20.11% of the mollusc shells (2168 valves) presented bioerosion traces, in 54 species (30 bivalves and 24 gastropods). Fourteen ichnogenera were reported: Entobia, Maeandropolydora, Iramena, Caulostrepsis, Pennatichnus, Pinaceocladichnus, Trypanites, and Gastrochaenolites (Domichnia), Gnathichnus and Radulichnus (Pascichnia), Finichnus and Centrichnus (Fixichnia), Oichnus (Praedicnia) (macrobioerosion), y Semidendrina (microbioerosion), the latter is first reported in mollusc shells in Argentina. Eleven ichnospecies were identified Finichnus peristroma, Maeandropolydora sulcans, Gnathichnus pentax, Pinaceocladichnus onubensis, Caulostrepsis taeniola, Centrichnus eccentricus, Radulichnus inopinatus, Oichnus simplex, Oichnus paraboloides, Oichnus gradatus, and Gastrochaenolites torpedo (lithic remains). The dominant ichnogenera in the Holocene deposits are Iramena, Entobia and Oichnus. The same ichnogenera are constant with different abundance in the modern beaches, and increasing representation of Pinaceocladichnus and Pennatichnus. The dominant ichnofacies in the Holocene deposits is Trypanites, revealing a benthonic marine community composed of cheilostome bryzoans, clionaid sponges, predator gastropods, regular echinoids, polychaete annelids, bivalves, thallophytas and fungi. Generally, the area was described as a sublittoral, low-energy, stable environment with high rate of oxygenation, and sandy bottoms, with rocky bottoms at Villalonga locality. 展开更多
关键词 molluscan BIOEROSION HOLOCENE south of Buenos aires Province
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Impact of Climate Change and Variability on Wheat and Corn Production in Buenos Aires, Argentina
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作者 Maria Pol Jacqueline Binyamin 《American Journal of Climate Change》 2014年第2期145-152,共8页
From the Global Historical Climate Network (GHCN-V3), monthly mean summer (DJF) temperature (1856-2012) and total precipitation (1861-2012) are analyzed in correlation with four climate modes and sunspot number to bet... From the Global Historical Climate Network (GHCN-V3), monthly mean summer (DJF) temperature (1856-2012) and total precipitation (1861-2012) are analyzed in correlation with four climate modes and sunspot number to better understand the role of teleconnections on Buenos Aires’ (Argentina) climate. A general increase in temperature and precipitation was observed. Temperature has increased by about 1.8°C and precipitation has increased by about 300 mm in the past century and a half. Indices of Arctic Oscillation (AO), Pacific North American (PNA), Antarctic Oscillation (AAO), and El Nino-Southern Oscillation (ENSO) are evaluated to study their effects on wheat and corn production and export. AO and PNA show strong relationships with precipitation and temperature received. AAO and ENSO show strong negative correlations with precipitation patterns and weak correlations with temperature. Sunspot Number shows a positive correlation with temperature. ENSO phases are strongly linked with the wheat and corn production and export;during El Nino Buenos Aires tends to experience extremely wet summer weather, causing soggy fields and extremely dry summer weather during La Nina causing drought. Both of these conditions result in reducing wheat and corn production and export. 展开更多
关键词 Climate Change of Buenos aires TELECONNECTIONS PNA AO SUNSPOT Number AAO ENSO WHEAT Corn Production and Export
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Patient Safety in the Use of Mechanical Restraints: Regulatory Compliance among Hospitals in the City of Buenos Aires and Proposal for Its Improvement
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作者 Martín Javier Mazzoglio y Nabar Sergio Giordano +3 位作者 Edgardo Knopoff Lorena Onofrio Oscar Agustín Porta Romina Rodríguez 《Open Journal of Emergency Medicine》 2024年第2期33-39,共7页
Introduction: Mechanical or physical restraint is an exceptional therapeutic resource to immobilize a subject and thus guarantee the safety of the patient and/or third parties in the face of high-risk behaviors, but i... Introduction: Mechanical or physical restraint is an exceptional therapeutic resource to immobilize a subject and thus guarantee the safety of the patient and/or third parties in the face of high-risk behaviors, but it entails multiple crossings (bioethical, philosophical, medical, psychological, legal). Framed in the so-called “safety culture” developed by the WHO, based on the Protocol for its implementation of the CABA and attentive to its frequent use in CABA by different hospital services (medical clinic, geriatrics, intensive care and medical guards) we consider it necessary its study in terms of compliance with the risks it entails and its management. Objectives: Identify regulatory compliance with the GCABA Mechanical restraint (MR) Protocol from a patient safety perspective, as well as describe the clinical and medicolegal aspects, and propose the usefulness of a tool for its management and control. Methodology: Observational, descriptive, transversal and prospective work through the analysis of Clinical Records with indication of MR using a rubric-type form. 177 cases were analyzed between September-November 2023 from three hospitals of the Government of the City of Buenos Aires, statistical parameters were applied and graphs were made. Results: Only 12.99% complied with the Protocol. In the mental health specialized hospital compliance was almost 5 times greater than in the general one, and in the emergency services compliance was 12 times greater than in Inpatient services. We found that the start or end time of MR was not recorded and only 43% described the causes/justifications for the indication (mostly in Emergency and Specialized hospitals), with the MR average time being shorter in Emergency. Conclusions: Only 1.3 out of 10 patients reliably completed the Protocol and it was mostly in the mental health specialized hospital and the emergency services. The results show non-compliance behavior in the application and management of the risk that the use of mechanical restraints entails, being causes for criminal litigation. We consider that the checklists are useful to complete the Protocol and thus provide security to patients and professionals. 展开更多
关键词 Mechanical Containment Patient Safety Injuries in Custody Buenos aires City Check List
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Health Effects of Climate and Air Pollution in Buenos Aires: A First Time Series Analysis
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作者 Rosana Abrutzky Laura Dawidowski +1 位作者 Patricia Matus Patricia Romero Lankao 《Journal of Environmental Protection》 2012年第3期262-271,共10页
Background: The impact of urban air pollution and temperature changes over health is a growing concern for epidemiologists all over the world and particularly for developing countries where fewer studies have been per... Background: The impact of urban air pollution and temperature changes over health is a growing concern for epidemiologists all over the world and particularly for developing countries where fewer studies have been performed. Aim: The main goal of this paper is to analyze the short term effects of changes in temperature and atmospheric carbon monoxide on daily mortality in Buenos Aires, Argentina. Methods: We conducted a time series study focused on three age groups, gender, and cardiovascular and respiratory mortality, with lags up to four days and temporal variables as modifiers. Results: Temperature correlates positively with total mortality for summer months, with a RR = 1.0184 (95%, CI 1.0139, 1.0229) on the same day for each 1℃ increase. In winter this relationship reverses, as 1?C temperature increase exhibit a protective effect with a RR = 0.9894 (95%, CI 0.9864, 0.9924) at the 3 day lag. Carbon monoxide correlates always positively with mortality, with a RR = 1.0369 (95%, CI 1.0206, 1.0534) for each 1 ppm increase, on the previous day. Conclusions: Climate and pollution parameters measured in Buenos Aires City exhibit a correlation with health outcomes. The impacts of temperature and carbon monoxide vary with age and gender, being elderly the most susceptible subgroup. One day after an increase in CO of 1 ppm, about 4% extra deaths can be expected. The correlation found between increases in CO and mortality for greater lags may be ascribed to the role of CO as a chemical marker of urban air pollution, indicating the co-presence of other pollutants. 展开更多
关键词 Health Air POLLUTION CLIMATE VARIABILITY Carbon MONOXIDE EPIDEMIOLOGY
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AIRES智能实时地震处理系统在稀疏台网下的应用:以2025年定日地震为例
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作者 夏登科 房立华 +5 位作者 蒋策 范莉苹 李君 吕帅 李帅 索朗占堆 《地球科学》 2026年第1期1-13,共13页
2025年1月7日西藏定日发生MW7.1地震,造成严重人员伤亡.利用定日地震周边12个固定台站与震后布设的6个流动台站数据,应用AIRES(Artificial Intelligence Real-time Earthquake processing System)智能实时地震处理系统对余震序列进行处... 2025年1月7日西藏定日发生MW7.1地震,造成严重人员伤亡.利用定日地震周边12个固定台站与震后布设的6个流动台站数据,应用AIRES(Artificial Intelligence Real-time Earthquake processing System)智能实时地震处理系统对余震序列进行处理,评估AIRES在稀疏台网下的应用效果.AIRES基于深度学习算法,自动从实时波形中完成地震检测、震相到时拾取、事件关联及震源参数反演.与人工目录对比表明,AIRES检测余震11242次,是人工目录的2.53倍,完备震级降至ML1.5;两个目录的平均震中差异为4.69 km、平均震源深度差异为5.71 km、平均震级差为-0.02.定日地震的余震分布在南北向长度约80 km,东西向宽度约30 km的区域内,并具有明显的分段和拐折特征.研究表明,在台网稀疏场景下,AIRES仍能保持稳健的检测能力与定位精度,可为密集地震序列实时监测和地震应急提供技术支撑. 展开更多
关键词 定日地震 aires 稀疏台网 余震序列 地震检测 地震学
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Environmental Regulation, Respiratory Diseases,and Medical Costs 被引量:2
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作者 Xiao Lei Lin Zhou Wentao Hu 《China & World Economy》 2026年第1期198-223,共26页
China implemented its Action Plan of Air Pollution Prevention and Control(APAPPC)in 2013 as a major step in national air-quality management.This study treated the APAPPC as a quasi-experiment,drawing on the Grossman a... China implemented its Action Plan of Air Pollution Prevention and Control(APAPPC)in 2013 as a major step in national air-quality management.This study treated the APAPPC as a quasi-experiment,drawing on the Grossman and Cropper models,to examine how air pollution affected individual health capital and medical service demand.Using panel data from the China Health and Retirement Longitudinal Study for 2011,2013,2015,and 2018,the analysis applied a Heckman two-stage model and difference-in-differences estimation to identify the policy's effects on medical expenditure.The results showed that the APAPPC significantly reduced annual health spending,with stronger effects among women,older adults,and rural residents.The mechanism analysis indicated that the reduction in respiratory diseases played a key role.This study provides evidence that supports further airpollution control in China and offers useful insights for other developing countries. 展开更多
关键词 Action Plan of Air Pollution Prevention and Control environmental regulation medical costs respiratory diseases
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Cross-flow boosts ultrafast-charging
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作者 Tuoya Naren Libao Chen Qichun Zhang 《Science China Materials》 2026年第3期1801-1802,共2页
With the advances of our society,the application scope of energy storage technologies has expanded dramatically,spanning diverse scenarios.These include electric air vehicles(EAVs)that require instantaneous high-power... With the advances of our society,the application scope of energy storage technologies has expanded dramatically,spanning diverse scenarios.These include electric air vehicles(EAVs)that require instantaneous high-power bursts for takeoff and maneuvering,portable medical devices demanding rapid rechargeability,and grid-connected energy storage systems that must swiftly respond to load fluctuations[1]. 展开更多
关键词 medical devices ultrafast charging energy storage electric air vehicles energy storage technologies electric air vehicles eavs cross flow portable medical devices
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Collaboration of GTCC-Powered CAES with Residual Compression Heat for Gas Turbine Inlet Air Heating
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作者 Cheng Yang Hanjie Qi Qing Yin 《Energy Engineering》 2026年第2期548-577,共30页
In order to enhance the off-peak performance of gas turbine combined cycle(GTCC)units,a novel collaborative power generation system(CPG)was proposed.During off-peak operation periods,the remaining power of the GTCC wa... In order to enhance the off-peak performance of gas turbine combined cycle(GTCC)units,a novel collaborative power generation system(CPG)was proposed.During off-peak operation periods,the remaining power of the GTCC was used to drive the adiabatic compressed air energy storage(ACAES),while the intake air of the GTCC was heated by the compression heat of theACAES.Based on a 67.3MW GTCC,under specific demand load distribution,a CPG system and a benchmark system(BS)were designed,both of which used 9.388% of the GTCC output power to drive the ACAES.The performance of the CPG and the BS without intake air heating was compared.The results show that the load rate of the GTCC in the CPG system during off-peak periods is significantly enhanced,and the average operating efficiency of the GTCC is increased by 1.19 percentage points.However,in the BS system,due to the single collaborativemethod of load shifting,the GTCC operative efficiency is almost increased by 1.00 percentage points under different ambient temperatures.In a roundtrip cycle at an ambient temperature of 288.15K,the systemefficiency of the CPG reaches 0.5010,which is 0.62 percentage points higher than the operative efficiency of 0.4948 in the standalone GTCC;while the system efficiency of the BS is slightly inferior to that of the standalone GTCC.The findings confirm the technical feasibility and performance improvement of the ACAES-GTCC collaborative power generation system. 展开更多
关键词 Gas turbine combined cycle adiabatic compressed air energy storage compressor inlet air heating collaborative power generation system system performance
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Associations of indoor airborne microbiome with systemic inflammation in the context of indoor particulate matter pollution and the metabolic mechanisms
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作者 Yetong Zhao Luyi Li +8 位作者 Wenlou Zhang Shan Liu Wanzhou Wang Xuezhao Ji Di Yang Lifang Zhao Zhihong Zhang Xinbiao Guo Furong Deng 《Journal of Environmental Sciences》 2026年第1期187-198,共12页
Microorganisms constitute an essential component in the indoor environment,which is closely related to hu-man health.However,there is limited evidence regarding the associations between indoor airborne microbiome and ... Microorganisms constitute an essential component in the indoor environment,which is closely related to hu-man health.However,there is limited evidence regarding the associations between indoor airborne microbiome and systemic inflammation,as well as whether this association is modified by indoor particulate matter and the underlying mechanisms.In this prospective repeated-measure study among 66 participants,indoor airborne mi-crobiome was characterized using amplicon sequencing and qPCR.Indoor fine particulate matter(PM_(2.5))and inhalable particulate matter(PM10)were measured.Systemic inflammatory biomarkers were assessed,including white blood cell(WBC),neutrophil(NEUT),monocyte,eosinophil counts,and their proportions.Targeted serum amino acid metabolomics were conducted to explore the underlying mechanisms.Linear mixed-effect models re-vealed that bacterial and fungal Simpson diversity were significantly associated with decreased WBC and NEUT.For example,for each interquartile range increase in the bacterial Simpson diversity,WBC and NEUT changed by-4.53%(95%CI:-8.25%,-0.66%)and-5.95%(95%CI:-11.3%,-0.27%),respectively.Notably,increased inflammatory risks of airborne microbial exposure were observed when indoor PM_(2.5) and PM10 levels were below the WHO air quality guidelines.Mediation analyses indicated that dopamine metabolism partially mediated the anti-inflammatory effects of fungal diversity exposure.Overall,our study indicated protection from a diverse indoor microbial environment on cardiovascular health and proposed an underlying mechanism through amino acid metabolism.Additionally,health risks associated with microbial exposure deserve more attention in con-texts of low indoor particulate matter pollution.Further research is necessary to fully disentangle the complex relationships between indoor microbiome,air pollutants,and human health. 展开更多
关键词 Indoor air BIOAEROSOLS MICROBIOME Particulate matter Systemic inflammation Amino acid metabolism
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Assessing the feasibility and environmental benefits of electrifying construction machinery in Beijing,China
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作者 Huawei Yi Yangyang Cui +6 位作者 Han Li Guanghan Huang Kaiyun Liu Linzhen Qu Jing Yan Lei Nie Yifeng Xue 《Journal of Environmental Sciences》 2026年第1期374-382,共9页
Oil-fired construction machinery(OCM)is a major source of urban air pollutants and CO_(2) emissions,and elec-trification is a crucial pathway for improving air quality and achieving China’s dual carbon goals;however,... Oil-fired construction machinery(OCM)is a major source of urban air pollutants and CO_(2) emissions,and elec-trification is a crucial pathway for improving air quality and achieving China’s dual carbon goals;however,its feasibility has not been fully explored.This study uses data envelopment analysis and the analytic hierarchy process to establish a development potential index,covering technical efficiency,economic cost,application sce-narios,and charging time and range,with an empirical analysis conducted in Beijing.The findings indicated the high feasibility of replacing OCM with electric alternatives,especially within the low-power range.Based on 2023 registered coding dat1,it is projected that by 2030,electrification could reduce regional average con-centrations of CO,NO_(x),PM_(2.5) and VOCs by 12.2%to 56.4%and reduce CO_(2) by 11.7%to 56.9%.Owing to economic considerations,small-and medium-sized machinery are particularly feasible for electrification.Key recommendations include prioritizing the electrification of forklifts,lifting platforms,and small-sized machinery in high-emission areas,particularly in central urban districts.Policies such as carbon taxes,carbon markets,and performance grading systems are suggested to incentivize electrification,along with expanding high-emission restriction zones and improving energy infrastructure to support widespread electrification. 展开更多
关键词 Construction machinery ELECTRIFICATION Data envelopment analysis Analytic hierarchy process Air pollution
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Numerical Analysis and Geometric Assessment of Air Layer Distribution in a Ventilated Planing Hull in Calm Water
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作者 Massimiliano Chillemi Filippo Cucinotta Felice Sfravara 《哈尔滨工程大学学报(英文版)》 2026年第1期46-62,共17页
The issue of resistance reduction through hull ventilation is of particular interest in contemporary research.This paper presents multiphase computational fluid dynamics(CFD)simulations with 2-DOF motion of a planing ... The issue of resistance reduction through hull ventilation is of particular interest in contemporary research.This paper presents multiphase computational fluid dynamics(CFD)simulations with 2-DOF motion of a planing hull.The original hull was modified by introducing a step to allow air ventilation.Following an assessment of the hull performance,a simulation campaign in calm water was conducted to characterize the hull at various forward speeds and air insufflation rates for a defined single step geometry.Geometric analysis of the air layer thickness beneath the hull for each simulated condition was performed using a novel method for visualizing local air thickness.Additionally,two new parameters were introduced to understand the influence of spray rails on the air volume beneath the hull and to indicate the primary direction of ventilated air escape.A validation campaign and an assessment of uncertainty of the simulation has been conducted.The features offered by the CFD methodology include the evaluation of the air layer thickness as a function of hull velocity and injection flow rate and the air volume distribution beneath the hull.The air injection velocity can be adjusted across various operating conditions,thereby preventing performance or efficiency loss during navigation.Based on these findings,the study highlights the benefits of air insufflation in reducing hull resistance for high-speed planing vessels.This work lays a robust foundation for future research and new promising topics,as the exploration of air insufflation continues to be a topic of contemporary interest within naval architecture and hydrodynamics. 展开更多
关键词 Computational fluid dynamics Air cavity ships Planing hull HYDRODYNAMICS Maritime sustainability
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A Comparative Review of the Experimental Mitigation Methods of the S-Shaped Diffusers in the Aeroengine Intakes
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作者 Hussain H.Al-Kayiem Safaa M.Ali +1 位作者 Sundus S.Al-Azawiey Raed A.Jessam 《Energy Engineering》 2026年第2期68-103,共36页
Gas Turbines are among the most important energy systems for aviation and thermal-based power generation.The performance of gas turbine intakes with S-shaped diffusers is vulnerable to flow separation,reversal flow,an... Gas Turbines are among the most important energy systems for aviation and thermal-based power generation.The performance of gas turbine intakes with S-shaped diffusers is vulnerable to flow separation,reversal flow,and pressure distortion,mainly in aggressive S-shaped diffusers.Severalmethods,including vortex generators and energy promoters,have been proposed and investigated both experimentally and numerically.This paper compiles a review of experimental investigations that have been performed and reported to mitigate flow separation and restore system performance.The operational principles,classifications,design geometries,and performance parameters of Sshaped diffusers are presented to facilitate the analysis and understanding of the influence of each mitigation method on flowenhancement in S-shaped diffusers.Theinfluencing design parameters on the performance of the S-shaped diffuser and the findings achieved by various experimental investigations are discussed and compared.The review concludes that reducing the intake length reduces the size and weight of the gas turbine,leading to a higher power-to-weight ratio.However,the main challenge in shortening the S-shaped diffusers is the flow separation in the high-curvature section,which must be prevented to maintain high performance.Prevention can be achieved through flow control methods,which are categorized into passive and aggressive methods.The static pressure recovery coefficient,total pressure loss coefficient,ideal static pressure coefficient,distortion coefficient,and skin friction coefficient are the primary performance evaluation and comparison parameters between the experimentally investigated mitigation methods.The new trend in S-shaped diffuser studies includes the integration of computational and data-driven methods. 展开更多
关键词 Active flow control AEROENGINE air intake distortion coefficient gas turbine passive flow control pressure recovery S-shaped diffuser
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Self-Activating Integrated Carbon-Based Air Cathodes With In Situ Oxygen Functionalization for Durable and High-Performance Metal-Air Batteries
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作者 Funing Bian Yuexi Chen +3 位作者 Hongfei Zhang Junfang Cheng Shulin Gao Sujuan Hu 《Carbon Energy》 2026年第1期176-186,共11页
Carbon-based air cathodes offer low cost,high electrical conductivity,and structural tunability.However,they suffer from limited catalytic activity and inefficient gas transport,and they typically rely on noble metal ... Carbon-based air cathodes offer low cost,high electrical conductivity,and structural tunability.However,they suffer from limited catalytic activity and inefficient gas transport,and they typically rely on noble metal additives or complex multilayer configurations.To tackle these issues,this study devised a self-activated integrated carbon-based air cathode.By integrating in situ catalytic site construction with structural optimization,the strategy not only induces the formation of oxygen functional groups(─C─OH,─C═O,─COOH),hierarchical pores,and uniformly distributed active sites,but also establishes a favorable electronic and mass-transport environment.Furthermore,the roll-pressing-based integrated design streamlines electrode construction,reinforces interfacial bonding,and significantly enhances mechanical stability.Density functional theory(DFT)calculations show that oxygen functional groups initiate hydrogen bonding interaction and promote charge enrichment,which improves the activity of the cathode and facilitates intermediate adsorption/desorption in oxygen reduction and evolution reactions processes.As a result,the integrated air cathode-based rechargeable zinc-air batteries(RZABs)achieve a high specific capacity of 811 mAh g^(-1).It also performs well in quasi-solid-state RZABs and silicon-air batteries systems across a wide temperature range,demonstrating strong adaptability and application potential.This study provides a scalable and cost-effective design strategy for high-performance carbon-based air cathodes,offering new insights into advancing durable and practical metal-air energy systems. 展开更多
关键词 integrated air cathode metal-air batteries ORR/OER oxygen functional group engineering SELF-ACTIVATION
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OptimizationDesign and Numerical Simulation of Variable Tube Diameter Heat Exchanger for Split Air Conditioning Indoor Unit
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作者 Zheming Cheng Xinping Ou Yang +2 位作者 Leren Tao Zihao Wang Ke Sun 《Frontiers in Heat and Mass Transfer》 2026年第1期288-313,共26页
Energy shortage has become one of themost concerning issues in the world today,and improving energy utilization efficiency is a key area of research for experts and scholars worldwide.Small-diameter heat exchangers of... Energy shortage has become one of themost concerning issues in the world today,and improving energy utilization efficiency is a key area of research for experts and scholars worldwide.Small-diameter heat exchangers offer advantages such as reduced material usage,lower refrigerant charge,and compact structure.However,they also face challenges,including increased refrigerant pressure drop and smaller heat transfer area inside the tubes.This paper combines the advantages and disadvantages of both small and large-diameter tubes and proposes a combined-diameter heat exchanger,consisting of large and small diameters,for use in the indoor units of split-type air conditioners.There are relatively few studies in this area.In this paper,A theoretical and numerical computation method is employed to establish a theoretical-numerical calculation model,and its reliability is verified through experiments.Using this model,the optimal combined diameters and flow path design for a combined-diameter heat exchanger using R32 as the working fluid are derived.The results show that the heat transfer performance of all combined diameter configurations improves by 2.79%to 8.26%compared to the baseline design,with the coefficient of performance(COP)increasing from 4.15 to 4.27~4.5.These designs can save copper material,but at the cost of an increase in pressure drop by 66.86%to 131.84%.The scheme IIIH,using R32,is the optimal combined-diameter and flow path configuration that balances both heat transfer performance and economic cost. 展开更多
关键词 Split air condition variable tube diameter enhanced heat transfer numerical simulation structural design optimization
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Stochastic assessment of residual fatigue life of railway axles considering relevant critical factors
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作者 Dušan Tichoň Tomáš Vojtek +6 位作者 Pavol Dlhý Pavel Pokorný Luboš Náhlík Alfonso Fernández-Canteli Rostislav Fajkoš Ondřej Peter Pavel Hutař 《Railway Engineering Science》 2026年第1期1-24,共24页
Statistical distribution of residual fatigue life(RFL)of railway axles under given loading was computed using the Monte Carlo method by considering random variation of the selected input parameters.Experimental data f... Statistical distribution of residual fatigue life(RFL)of railway axles under given loading was computed using the Monte Carlo method by considering random variation of the selected input parameters.Experimental data for the EA4T railway axle steel,the loading spectrum,the press fit loading and the residual stress induced by surface hardening were considered in the crack propagation simulations.Usually,the material properties measured by tensile tests are considered to be the most informative source of material data.Under fatigue loading,however,the crack growth rates near the threshold are the most critical data.Two important influencing factors on these crack growth rates are presented:first,the air humidity and,second,the near-surface residual stress.The typical variation of these parameters in operation may change the RFL by one or two orders of magnitude.Experimentally obtained crack growth thresholds and residual stress profiles are highly affected by the used methodology.Therefore,the obtained input data may be located anywhere within a large scatter,while the experimenters are completely unaware of it.This can lead to dangerously non-conservative situations,e.g.when the thresholds are measured in a laboratory under humid air conditions and then applied to predictions of RFLs of axles operated in winter in low air humidity.This is significant for the topic of inspection interval optimisation.The results of experiments done on real 1:1 railway axles were close to the most frequent value found in the histogram of the numerically computed RFLs. 展开更多
关键词 Residual fatigue life Railway axles Fatigue crack Growth threshold Air humidity Monte Carlo method
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Designing an air electrode for dual ceramic cells using an ionic Lewis acid strength polarization distribution strategy
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作者 Ying Zhang Yibei Wang +8 位作者 Zhilin Liu Yaowen Wang Zhen Wang Youcheng Xiao Bingbing Niu Xiyang Wang Guntae Kim Wenquan Wang Tianmin He 《Journal of Energy Chemistry》 2026年第1期505-516,I0012,共13页
Ceramic cells promise ideal energy conversion and storage devices,making the development of efficient and robust air electrodes crucial for their application.In this study,a Ba_(0.4)Sr_(0.5)Cs_(0.1)Co_(0.7)Fe_(0.2)Nb_... Ceramic cells promise ideal energy conversion and storage devices,making the development of efficient and robust air electrodes crucial for their application.In this study,a Ba_(0.4)Sr_(0.5)Cs_(0.1)Co_(0.7)Fe_(0.2)Nb_(0.1)O_(3−δ)(BSCCFN)air electrode,based on Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3−δ)(BSCF),is designed using a perovskite A-B-site ionic Lewis acid strength(ISA)polarization distribution strategy and is successfully applied in both oxygen-ion conducting solid oxide fuel cells(O-SOFCs)and proton-conducting reversible protonic ceramic cells(R-PCCs).When BSCCFN is used as the air electrode in O-SOFCs,a peak power density(PPD)of 1.45 W cm^(−2)is achieved at 650°C,whereas in R-PCCs,a PPD of 1.13 W cm^(−2)and a current density of−1.8 A cm^(−2)at 1.3 V are achieved at the same temperature and show stable reversibility over 100 h.Experimental measurements and theoretical calculations demonstrate that low-ISA Cs+doping accelerates the reaction kinetics of both oxygen ions and protons,while high-ISA Nb^(5+)doping enhances electrode stability.The synergistic effect of Cs^(+)and Nb^(5+)co-doping in the BSCCFN electrode lies in the ISA polarization distribution,which weakens the Co/Fe–O bond covalency,thereby promoting oxygen vacancy formation and facilitating the conduction of oxygen ions and protons. 展开更多
关键词 Air electrode Ceramic cell Electrochemical performance lonic Lewis acid strength polarization distribution Co/Fe-O bond
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Transmission pathways and potential source regions for atmospheric fine particulate matter and ozone in Urumqi
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作者 Aifang Gao Wanting Sun +4 位作者 Xi You Chenglong Liao Baojun Zhang Mengyue Wang Hongliang Zhang 《Journal of Environmental Sciences》 2026年第1期683-693,共11页
To understand the transmission paths and potential source areas of fine particulate matter(PM_(2.5))and ozone(O_(3))in Urumqi,using the monitoring data from 2020 to 2022,the pollution characteristics and the transmiss... To understand the transmission paths and potential source areas of fine particulate matter(PM_(2.5))and ozone(O_(3))in Urumqi,using the monitoring data from 2020 to 2022,the pollution characteristics and the transmission paths of PM_(2.5) and O_(3) were studied.Based on the MeteoInfo software,the potential source areas and concentration contributions via the weighted potential source contribution function(WPSCF)and the weighted concentration weighted trajectory(WCWT)were analyzed.Besides,trajectory distribution at different starting heights were compared.The results of the backward trajectory(500 m)showed that the PM_(2.5) and O_(3) clustering trajectories were mainly derived from the northwest and passed through Yining/Ili and Tacheng.The air flow proportion of PM_(2.5) pollution was 44.83%in winter.With the highest pollution concentration(119.2μg/m^(3)),the pollution airflow proportion of O_(3) was 30.52%in summer.According to an analysis of the pressure profile,the atmospheric pressure was below 850 hPa in winter,indicating that the near-surface air mass had a substantial impact on PM_(2.5) concentrations,whereas in summer the pressure for O_(3) rose above 750 hP1,leading to higher pollutant concentrations.The WPSCF/WCWT results of PM_(2.5) demonstrated that the largest potential areas were identified in winter and were mainly distributed in Bozhou,Kuitun,and Shihezi(west of Urumqi,cultivated land/grassland),while the largest potential areas of O_(3) were distributed in Changji(east of Urumqi,barren land)and Turpan(southeast of Urumqi,grassland)in summer.The study indicates that the government should implement stricter measures to control regional transmission and air pollution. 展开更多
关键词 URUMQI Air pollution PM_(2.5)and O_(3) Potential sourceanalysis Backward trajectory
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Residential greenness,air pollution,and incident age-related macular degeneration:A prospective cohort study
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作者 Jiali Wang Yinyan Gao +2 位作者 Yijuan Lin Irene X.Y.Wu Fang Xiao 《Journal of Environmental Sciences》 2026年第1期242-249,共8页
Existing evidence suggests residential greenness is beneficial to human,while no research to date explored the associations of greenness with age-related macular degeneration(AMD).To evaluate the association of greenn... Existing evidence suggests residential greenness is beneficial to human,while no research to date explored the associations of greenness with age-related macular degeneration(AMD).To evaluate the association of greenness with AMD,modification and mediation effect of air pollution,we conducted this prospective study.We con-structed weighted quantile sum(WQS)index as co-exposure to nitrogen oxides(NO_(x)),particulate matter<2.5μm(PM_(2.5)),particulate matter<10μm(PM10).Stratified Cox regression models were applied to test the effect of exposure.Effect modification of air pollution was assessed.Stratified Cox models through the indirect method and Aalen additive risk models were used in mediation analysis.Over median follow-up of 11.67 years,4596 AMD events were ascertained.Hazard ratios(HRs)and 95%confidence intervals(95%CIs)of incident AMD for pollution per interquartile range(IQR)increment were 1.10(1.04–1.16)for nitrogen dioxide(NO_(2)),1.09(1.03–1.15)for NO_(x),1.14(1.05–1.24)for PM_(2.5),1.13(1.05–1.21)for PM10.The HR(95%CI)of AMD associated with greenness 1000 m buffer per IQR increment was 0.91(0.86–0.97),300 m buffer was 0.94(0.89–0.99).The as-sociation between greenness 1000 m and AMD was 28.59%,44.77%,35.59%,32.31%and 27.08%mediated by the decreased WQS index,NO_(2),NO_(x),PM_(2.5) and PM10,respectively.Increased greenness was associated with lower AMD incidence,and air pollution partly mediate it,which implies that interventions aimed at improving air quality and increasing greenness could have a dual benefit in mitigating AMD risk. 展开更多
关键词 Age-related macular degeneration(AMD) Residential greenness Ambient air pollution Mediation effect Prospective cohort study
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Long-range masked autoencoder for pre-extraction of trajectory features in within-visual-range maneuver recognition
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作者 Feilong Jiang Hutao Cui +2 位作者 Yuqing Li Minqiang Xu Rixin Wang 《Defence Technology(防务技术)》 2026年第1期301-315,共15页
In the field of intelligent air combat,real-time and accurate recognition of within-visual-range(WVR)maneuver actions serves as the foundational cornerstone for constructing autonomous decision-making systems.However,... In the field of intelligent air combat,real-time and accurate recognition of within-visual-range(WVR)maneuver actions serves as the foundational cornerstone for constructing autonomous decision-making systems.However,existing methods face two major challenges:traditional feature engineering suffers from insufficient effective dimensionality in the feature space due to kinematic coupling,making it difficult to distinguish essential differences between maneuvers,while end-to-end deep learning models lack controllability in implicit feature learning and fail to model high-order long-range temporal dependencies.This paper proposes a trajectory feature pre-extraction method based on a Long-range Masked Autoencoder(LMAE),incorporating three key innovations:(1)Random Fragment High-ratio Masking(RFH-Mask),which enforces the model to learn long-range temporal correlations by masking 80%of trajectory data while retaining continuous fragments;(2)Kalman Filter-Guided Objective Function(KFG-OF),integrating trajectory continuity constraints to align the feature space with kinematic principles;and(3)Two-stage Decoupled Architecture,enabling efficient and controllable feature learning through unsupervised pre-training and frozen-feature transfer.Experimental results demonstrate that LMAE significantly improves the average recognition accuracy for 20-class maneuvers compared to traditional end-to-end models,while significantly accelerating convergence speed.The contributions of this work lie in:introducing high-masking-rate autoencoders into low-informationdensity trajectory analysis,proposing a feature engineering framework with enhanced controllability and efficiency,and providing a novel technical pathway for intelligent air combat decision-making systems. 展开更多
关键词 Within-visual-range maneuver recognition Trajectory feature pre-extraction Long-range masked autoencoder Kalman filter constraints Intelligent air combat
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