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Influence of biomass burning on ozone levels in the Megalopolis of Central Mexico during the COVID-19 lockdown

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j.urnal of Environmental Sciences 2024年第9期143卷 99-115页

作者： Victor Almanza Luis Gerardo Ruiz-Suárez Ricardo Torres-j.rdón Agustín García-Reynoso Iván Y.hernández-Paniagua Institute for Atmospheric Sciences and Climate Change National Autonomous University of MexicoCoyoacan 04510Mexico CityMexico

The massive reductions in anthropogenic emissions resulting from the COVID-19 lockdown provided a unique opportunity to evaluate the effect of mitigation measures aiming to abate air *** Mexico,the total lockdown period took place during the dry-hot season when biomass burning activity is ***,we investigate the role of biomass burning emissions on regional ozone levels in the Megalopolis of Central *** studied period covers the lockdown phases 2 and 3,and the first month of the New *** applied a factor separation technique and process analysis to estimate the pure and synergistic contributions of emission reductions under lockdown and that from biomass burning to daily ozone maximum concentrations in 7 metropolitan areas of different states in the *** results revealed that biomass burning plumes likely masked the effect of massive reductions from mobile emissions,impacted the PBL development during phase 3 and favored transition and mixed NO_(x)-limited and VOC-limited regional *** contributed to increased ozone production in the middle to lower PBL by changing the regional background levels which potentially could bias high ozone production efficiency *** the Megalopolis contribution to economic and societal development at national scale,our study suggests that ozone mitigation measures during the dry-hot season targeting mainly mobile emissions will likely be offset by biomass burning plumes.A regional and synergic policy aiming to control biomass burning would help to reduce the occurrence of high ozone levels in Central Mexico with the co-benefit of tackling short-lived climate pollutants.

关键词： COVID-19 Mexico Megalopolis Ozone Factor Separation Process Analysis

Appraisal of Surface Modified AISI 316 L Stainless Steels by Plasma and Solid Nitriding Techniques

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Materials Sciences and Applications 2020年第7期11卷 462-473页

作者： R. Guardian I. Rosales-Cadena j. L. Valle-Mata j. pereyra-hernández O. Ocampo Center of Research in Engineering and Applied Science CIICAp - UAEM. Cuernavaca Mexico

AISI 316 L stainless steels type was surface modified by ion and solid nitriding treatment. It was demonstrated that a surface activation pretreatment in samples based in acid mixture accompanied with NH4NO3 solution inside the container, can produce an efficient nitrogen diffusion process. As compared with ion nitriding treatment (20%N2-80%H2), the samples were treated with solid nitriding technique, using Fe4KCN based compound at the same time and temperature (6 h and 500°C respectively). Superficial layers with a depth of 45 μm average were obtained with six hours treatment. Hardness surface values of two surface treatments present an increased value of approximately three times with respect to the matrix sample. Wear evaluation indicated low regimes of weight losses for both treatments. Oxidative-adhesive result is to be the predominant operating wear mechanism. Positive results were obtained in solid nitriding technique as compared with the expensive ion nitriding technique.

关键词： Surface Modification Hardness Mechanical Properties Wear

Synthesis and Characterization of Heat Treated Cu-Al alloys for Energy Applications

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j.urnal of Materials Science and Chemical Engineering 2019年第11期7卷 22-30页

作者： j. pereyra-hernández O. Ocampo R. A. Falcon-Castrej.n I. Rosales-Cadena j. A. Ruiz-Ochoa Centro de Investigación en Ingeniería y Ciencias Aplicadas UAEM Chamilpa Cuernavaca Morelos México Facultad de Ciencias de la Ingeniería y Tecnología UABC Tijuana Baja California México

Three alloys with different atomic percent (at. %) Cu-Al were designed and synthetized, using an electromagnetic induction furnace system. Alloys were designed in a substitutional way, varying the Al content respect to Cu, from 10 to 50 at. %. Microstructure changes from dendritic structure to equiaxed grains depending the heat treatment. Hardness test evaluation has shown values in the order of 700 kg/mm2 which represents an increment of 600 percent, while compression tests have shown an important strengthening increment. Besides, electrical resistivity test was carried out, in order to analyze a future application in an electrochemical system, obtaining an improvement three times more in comparison with the unalloyed sample. Strengthening results were interpreted in terms of defects generation, caused by the thermal treatments.

关键词： Solid Solution Mechanical Properties Heat Treatments Electrical Properties

Optical magnetic field enhancement using ultrafast azimuthally polarized laser beams and tailored metallic nanoantennas

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Photonics Research 2024年第5期12卷 1078-1092页

作者： RODRIGO MARTIN-hernAndez LORENZ GRUNEWALD LUIS SANCHEZ-TEj.RINA LUIS PLAj. ENRIQUECONEj.RO j.RQUE CARLOS hernAndez-GARCIA SEBASTIAN MAI Grupo de Investigacion en Aplicaciones del Laser y Fotonica Departamento de Fisica AplicadaUniversidad de SalamancaE-37008 SalamancaSpain Unidad de Excelencia en Luz y Materia Estructuradas(LUMES) Universidad de SalamancaE-37008 SalamancaSpain Institute of Theoretical Chemistry Faculty of ChemistryUniversity of Vienna1090 ViennaAustria Vienna Doctoral School in Chemistry(DoSChem) Faculty of ChemistryUniversity of Vienna1090 ViennaAustria Departamento de Electricidad y Electrónica Universidad de Valladolid47011 ValladolidSpain

*** *** thank Valentina Shumakova,Elizaveta Gangrskaia,Alessandra Bellissimo,Audrius Pugzlys,and Andrius Baltu?ka for fruitful discussions and computational support by the Vienna Scientific Cluster(VSC 4).The authors thankfully acknowledge the computer resources at MareNostrum and SCAYLE,and the technical support provided by Barcelona Supercomputing Center(RES-FI-2022-3-0041).R.M.-H.,L.S.-T.,L.P.,E.C.j.,and C.H.-*** funding from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation program(Grant Agreement No.851201)and support from Ministerio de Ciencia e Innovación(PID2022-142340NB-I00,PID2019-106910GB-I00).This research was funded in whole or in part by the Austrian Science Fund(FWF)(10.55776/ZK91).For open access purposes,the author has applied a CC BY public copyright license to any author accepted manuscript version arising from this submission.

关键词： metallic polarized discussions

Timing and Spectral Analysis of the Black Hole X-Ray Binary MAXI j.803-298 with Insight-HXMT Data

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Research in Astronomy and Astrophysics 2024年第6期24卷 209-224页

作者： Ying-Chen Xu j.n-Lu Qu MMéndez Rui-Can Ma Long j. Liang Zhang Yue Huang Qing-Cui Bu Li-Ming Song Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China Kapteyn Astronomical Institute University of GroningenP.O.BOX 8009700 AV GroningenThe Netherlands Dongguan Neutron Science Center Dongguan 523808China School of Physics and Astronomy Sun Yat-Sen UniversityZhuhai 519082China Institut für Astronomie und Astrophysik Kepler Center for Astro and Particle PhysicsEberhard Karls UniversitätSand 1D-72076 TübingenGermany

We present a comprehensive analysis of the 2021 outburst of MAXI j.803–298 utilizing observations of the Insight-Hard X-ray Modulation Telescope(Insight-HXMT)spanning from the low hard state to the high soft *** the Insight-HXMT data set,compared to the previous work,we identify a more prolonged presence of typeC quasi-periodic oscillations(QPOs)with centroid frequencies ranging from~0.16 to 6.3 Hz,which present correlations with the hardness ratio and the photon index of the Comptonized *** QPO frequencies less than~2 Hz,the QPO phase lags are hard(photons of 10–19 keV arrive later than those of 1–4 keV),while at higher frequencies,the lags become soft at and above~4 ***,the spectra in all Insight-HXMT observations consist of a multi-color blackbody component and a Comptonized component,as commonly observed in classical black hole X-ray *** analyze state transitions and the evolution of accretion geometry in this *** fitted inner disk radius increases abnormally during the low hard state,hypothesized to result from the corona condensing onto the inner ***,two significant drops in flux are observed during the soft intermediate state,maybe implying changes in the corona/j.t and the disk,respectively.

关键词： X-rays:binaries accretion accretion disks stars:black holes

Efficiency and effectiveness of systems for the treatment of domestic wastewater based on subsurface flow constructed wetlands in j.rabacoa, Dominican Republic

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Water Science and Engineering 2024年第2期17卷 118-128页

作者： Yvelisse Pérez Enmanuel Vargas Daniel Garcia-Cortes William hernandez Humberto Checo Ulises j.uregui-Haza Area de Ciencias Basicas y Ambientales Instituto Tecnologico de Santo Domingo(INTEC)Avenida de Los Proceres 49Los Jardines del NorteSanto Domingo 10602Dominican Republic Ministry of Environment and Natural Resources Calle Cayetano Germosen esq.Ave.LuperonEl PedregalSanto Domingo 11107Dominican Republic Plan Yaque Calle Estela Geraldino 14 AltosJarabacoa 41000Dominican Republic Institute of Technologies and Applied Sciences University of HavanaHavana 10400Cuba

Constructed wetlands(CwW)are well known nature-based systems for water *** study evaluated the efficiency and effectiveness of seven domestic wastewater treatment systems based on horizontal flow CWs in j.rabacoa,the Dominican *** results showed that the CWs were efficient in reducing the degree of contamination of wastewater to levels below the Dominican wastewater discharge standards for parameters such as the 5-day biochemical oxygen demand(BOD5)and chemical oxygen demand,but not for the removal of phosphorus and fecal *** addition,a horizontal flow subsurface wetland in the peri-urban area El Dorado was evaluated in terms of the performance of wastewater treatment in tropical climatic *** concentrations of heavy metals,such as zinc,copper,chromium,and iron,were found to decrease in the effluent of the wetland,and the concentrations for nickel and manganese tended to *** levels of heavy metals in the effluent were lower than the limit values of the Dominican wastewater discharge *** construction cost of these facilities was around 200 USD per population equivalent,similar to the cost in other countries in the same *** study suggested some solutions to the improved performance of CWs:selection of a microbial flora that guarantees the reduction of nitrates and nitrites to molecular nitrogen,use of endemic plants that bioaccumulate heavy metals,combination of constructed wetlands with filtration on activated carbon,and inclusion of water purification processes that allow to evaluate the reuse of treated water.

关键词： Domestic wastewater Constructed wetland BOD COD Pathogens Heavy metals

Bismuth-based halide double perovskite Cs_(2)KBiCl_(6): Disorder and luminescence

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Chinese Chemical Letters 2024年第5期35卷 504-508页

作者： Pan Liu Yanming Sun Alberto j.Fernández-Carrión Bowen Zhang Hui Fu Lunhua He Xing Ming Congling Yin Xiaoj.n Kuang MOE Key Laboratory of New Processing Technology for Nonferrous Metal and Materials Guangxi Key Laboratory of Optic and Electronic Materials and DevicesCollege of Materials Science and EngineeringGuilin University of TechnologyGuilin 541004China Analytical Instrumentation Center College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Spallation Neutron Source Science Center Dongguan 523803China Chinese Academic of Science Institute of PhysicsBeijing National Laboratory for Condensed Matter PhysicsBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China College of Science Guilin University of TechnologyGuilin 541004China College of Chemistry and Bioengineering Guilin University of TechnologyGuilin 541004China

A new bismuth-based halide double perovskite Cs_(2)KBiCl_(6) was isolated successfully through solid-state reactions and investigated using X-ray and neutron *** than an ordered structure,the crystal structure consists of shifted Cs,K,Bi,and Cl sites from the ideal positions with fractional occupancy in compensation,leading to variable local coordination of Cs^(+)ions,as revealed by^(133)Cs solid-state nuclear magnetic resonance ***_(2)KBiCl_(6) displays volume hysteresis at 5-298 K range upon heating and *** Cs_(2)KBiCl_(6) has a direct bandgap of 3.35(2)eV and red-shift luminescence of around 600 nm upon Mn doping compared with the Na *** stabilization of disordered structure in Cs_(2)KBiCl_(6) is related to two factors including the large-sized K^(+)cation which prefers to coordinate with more than six Cl^(-),and the Bi^(3+)with 6s^(2) lone pair which has a preference for a local asymmetric *** findings could have general application and help to understand the structure and property of halide perovskites.

关键词： Halide perovskite Double perovskite Luminescence Disordered structure Direct bandgap

Editorial for the Special Issue on Emerging Technology and Advanced Application of Nondestructive Detection for Power Equipment

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Chinese j.urnal of Electrical Engineering 2024年第1期10卷 1-2页

作者： Li j. Mei H. Li S. Tianj.n University China Tsinghua Shenzhen International Graduate School China Lanzhou j.aotong University China

The rapid development of clean and renewable energy technologies represented by wind and solar energy,as well as the continuous growth of load demand,have put forward higher requirements for the safe operation of the power *** performance of power equipment based on traditional dielectric materials is often limited by various defects generated during molding,transportation,assembly,and operation,which cannot meet the reliability requirements of power systems in the new *** detection is an essential technical method in industrial development,which can detect and evaluate the defect and damage status of in-service equipment,key components,and materials without damaging the obj.ct.

关键词： service Application operation

Annual variation of adult survival of a south-temperate House Wren population in Argentina

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Avian Research 2024年第2期15卷 229-237页

作者： Gustavo j.Fernandez Mariana E.Carro Paulo E.Llambías Grupo de Investigacion en Ecofisiología de Fauna Silvestre INIBIOMA-CONICETAsentamiento Universitario San Martín de los Andes(AUSMA)Universidad Nacional Del ComahuePasaje de la Paz 235(8370)San Martín de los AndesNeuquenArgentina Grupo de Investigacion de Biología de Aves IADIZA CCT-MendozaUniversidad Nacional de CuyoAvenida RuizLeal s/n Parque General San Martin5500MendozaArgentina

Identifying factors affecting the survival of individuals is essential for understanding the evolution of life-history traits and population *** numerous studies on this subj.ct in north-temperate environments,there is a lack of equivalent studies at similar latitudes in the ***,we used a 14-year dataset of capture,banding,and resighting to estimate the annual variation in the apparent adult survival probability of a south-temperate population of House Wrens(Troglodytes aedon bonariae).We evaluated temporal variation in sur-vival and the effect of environmental(climatic)and demographic variables(adult abundance,total number of fledglings produced during each breeding season)on survival *** found that the probability of adult survival decreased as the abundance of breeding adults *** density-dependent effect could be related to the resident lifestyle of southern House Wrens,which could determine an intense competition for territories and resources that ultimately would affect their survival.

关键词： Annual variation Cj. Density-dependence Survival Troglodytes aedon bonariae