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Impacts of climate change in Portugal:common Perception of causes and consequences in Forest Development

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Research in Ecology 2019年第2期1卷 24-30页

作者： L.J.R.nunes c.I.R.meireles c.J.Pinto Gomes n.m.c.almeida ribeiro IcAAm-Instituto de ciências Agrárias e Ambientais mediterrânicas Universidade deÉvora7000-083ÉvoraPortugal Departamento da Paisagem Ambiente e OrdenamentoUniversidade deÉvora7000-671ÉvoraPortugal Departamento de Fitotecnia Universidade deÉvora7000-083ÉvoraPortugal

Presently the world faces what most likely will be the greatest challenge humanity has ever *** change is a phenomenon,or rather a set of phenomena,that directly influences the daily lives of human populations all over the ***,this influence normally negative also affects ecosystems,with emphasis on agroforestry systems,of which human populations are directly dependent on food and in a large number of primary raw *** is with this premise as a starting point that this work makes an analysis on the current state of climate change in Portugal,since,being a country of mediterranean climate influence,it should be one of the territories where changes will be felt with more intensity and *** this work,the current position on energy production in Portugal regarding Green House Gases(GHGs)emissions and the evolution prospects for the near future,namely in the perspective of the impacts caused on forest resources,are discussed.

关键词： climate change Forest management Renewable energies Green House Gases(GHGs)

Langmuir-Schaefer Film Investigation and Density Functional Theory Band Gap calculations of calix[n]arene-Para-Aminobenzoic Acid for Drug nanosensor Application

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Journal of Wuhan University of Technology(materials Science) 2024年第5期39卷 1311-1318页

作者： WOnG Yeong Yi F L Supian A Radzwan m musa n F n Abd Karim Department of Physics Sultan Idris Education UniversityTanjong Malim 35900Malaysia Department of chemistry Sultan Idris Education UniversityTanjong Malim 35900Malaysia

calix[n]arenes was utilized to detect PABA,the primary sunscreen *** study investigates the interaction of calix[4]arene(c4),calix[6]arene(c6),and PABA using the Langmuir method and first-principle density functional theory(DFT).Using the Langmuir-Schaefer(LS)technique,an ultrathin film composed of calix[n]arenes and their complexes with PABA was deposited on various *** on the Langmuir study,the PABA molecule was bonded to the lower rims of both c4 and c6 with the host-guest ratio of 1:*** of the LS films formed were then characterized by ultravioletvisible spectroscopy(UV-Vis),Fourier-transform infrared spectroscopy(FTIR)and carbon,hydrogen,nitrogen,sulfur elemental analyzer(cHnS).The band gap reduction obtained in the DFT study denotes the charge transfer interaction with promising reactivity between the calix[n]arenes and *** sensing of PABA by c4 and c6 is successful based on the formation of bonding between them due to the hosts’effective trapping *** outcomes of this study could be applied to drug delivery systems for future pharmaceutical and medical applications.

关键词： calix[n]arenes band gap density functional theory Langmuir-Schaefer PABA sensor

Single atom cu-n-c catalysts for the electro-reduction of cO_(2) to cO assessed by rotating ring-disc electrode

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Journal of Energy chemistry 2024年第1期88卷 169-182,I0004页

作者： S.Pérez-Rodríguez m.Gutiérrez-Roa c.Giménez-Rubio D.Ríos-Ruiz P.Arévalo-cid m.V.martínez-Huerta A.Zitolo m.J.Lázaro D.Sebastián Instituto de carboquímica(cSIc) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de catálisis y Petroleoquímica(cSIc) Marie Curie 228049 MadridSpain Synchrotron SOLEIL L’Orme des MerisiersDépartementale 12891190France

The electrochemical cO_(2) reduction reaction(cO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(cu-n-c) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient cO_(2)RR. The electrocatalytic performance of cu-n-c materials is assessed by a rotating ring-disc electrode(RRDE), technique still rarely explored for cO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized cu-nc catalysts are found to be active and highly cO selective at low overpotentials(from -0.6 to -0.8 V ***) in 0.1 m KHcO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing cu-n_(4) moieties exhibits a cO_(2)-to-cO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/cO ratio of 1.8. These results demonstrate that RRDE configuration can be used as a feasible approach for identifying electrolysis products from cO_(2)RR.

关键词： cu-n-c carbon xerogel Rotating ring disc electrode carbon dioxide reduction reaction carbon monoxide

Empirical model for fusion cross sections of ca-induced reactions

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chinese Physics c 2024年第3期48卷 126-132页

作者： Reddi Rani.L n.Sowmya K.n Sridhar H c.manjunatha m.m.Armstrong Arasu Department of Physics St.Joseph's College(Autonomous)Affiliated to Bharathidasan UniversityTiruchirappalli620002TNIndia Department of Physics Govt.First.Grade CollegeChikkaballapur-562101KarnatakaIndia Department of Physics Govt.First.Grade CollegeMalur-563160KarnatakaIndia Department of Physics Govt.First.Grade CollegeDevanahalli-562110KarnatakaIndia

A new empirical formula for the astrophysical S-factor has been suggested as a function of the coulomb interaction parameter,center of mass energy,and barrier *** 22 fusion reactions with ^(40,48)ca as projectiles were considered for different targets,leading to compound nuclei with atomic and mass numbers varying between 40≤Z≤≤Z≤112 and 88≤A≤27888≤A≤278,*** fusion cross-sections have been estimated using the geometric factor,the Gamow-Sommerfield factor,and the empirical formula for the *** study's findings showed better agreement with those of available experiments when compared to Wong's *** present work leads to a smaller standard deviation value than Wong's formula when used to correlate the experimental data of calcium-induced fusion ***'s formula provides a good approximation of fusion cross-sections when the center of mass energy is below the fusion barrier when compared to above the fusion barrier.

关键词： fusion cross-sections Wong formula Gamow-Sommerfield-factor Geometric-factor S-factor

Assessing trends in wildland-urban interface fire research through text mining: a comprehensive analysis of published literature

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Journal of Forestry Research 2024年第4期35卷 102-114页

作者： Hafsae Lamsaf Asmae Lamsaf mounir A.Kerroum miguel almeida ADAI–Associação para o Desenvolvimento da Aerodinâmica Industrial Rua Pedro Hispano n.º123030‑289 CoimbraPortugal Laboratory of Research in computer Science Faculty of SciencesIbn Tofail UniversityKenitraMorocco

Research on fires at the wildland-urban inter-face(WUI)has generated significant insights and advance-ments across various fields of ***,agri-culture,and social sciences have played prominent roles in understanding the impacts of fires in the environment,in protecting communities,and addressing management *** study aimed to create a database using a text mining technique for global researchers interested in WUI-projects and highlighting the interest of countries in this ***’s-Keywords analysis emphasized the dominance of fire science-related terms,especially related to WUI,and identified keyword clusters related to the WUI fire-risk-assessment-system-“exposure”,“danger”,and“vulnerability”within wildfire *** over the past decade showcase shifting research interests with a growing focus on WUI fires,while regional variations highlighted that the“exposure”keyword cluster received greater atten-tion in the southern Europe and South ***,vulnerability keywords have relatively a lower representation across all *** analysis underscores the interdisci-plinary nature of WUI research and emphasizes the need for targeted approaches to address the unique challenges of the wildland-urban ***,this study provides valu-able insights for researchers and serves as a foundation for further collaboration in this field through the understanding of the trends over recent years and in different regions.

关键词： WUI Text mining Wildfires Fire science State of the art Scientific publications

Liquid crystal immunosensors for the selective detection of Escherichia coli with a fast analysis tool

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Photonics Research 2024年第7期12卷 1564-1573页

作者： SAnDRO c.OLIVEIRA mARIA S.SOARES BÁRBARA V.GOnÇALVES AnDREIA c.m.RODRIGUES AmADEU m.V.m.SOARES RITA G.SOBRAL nUnO F.SAnTOS JAn nEDOmA PEDRO L.almeida cARLOS mARQUES cIcEcO-Aveiro Institute of materials Physics DepartmentUniversity of Aveiro3810-193 AveiroPortugal i3n Physics DepartmentUniversity of Aveiro3810-193 AveiroPortugal Associate Laboratory i4HB-Institute for Health and Bioeconomy School of Sciences and TechnologyNOVA University of Lisbon1099-085 LisbonPortugal cESAm-centre for Environmental and marine Studies and Department of Biology University of Aveiro3810-193 AveiroPortugal Department of Telecommunications VSB-Technical University of OstravaOstrava 70800Czech Republic i3n-cEnImAT School of Sciences and TechnologyNOVA University of Lisbon1099-085 LisbonPortugal UnIRE ISELPolytechnic Institute of Lisbon1549-020 LisbonPortugal Department of Physics VSB-Technical University of OstravaOstrava 70800Czech Republic

The consumption of contaminated food may cause serious illnesses,and traditional methods to detect Escherichia coli are still associated with long waiting times and high costs given the necessity to transport samples to specialized *** is a need to develop new technologies that allow cheap,fast,and direct monitoring at the site of ***,in this work,we developed optical immunosensors for the selective detection of ***,based on liquid crystal technology,whose molecules can align in different manners depending on the boundary conditions (such as substrates) as well as the environment that they *** glass substrate was functionalized with *** antibody using cysteamine as an intermediate,and a vertical alignment was imposed on the liquid crystal molecules by using DmOAP during *** presence of bacteria disrupts the alignment of the liquid crystal molecules,changing the intensity of light emerging between cross polarizers,measured using a polarized optical microscope and a *** was possible to detect *** in suspensions in the concentration range from 2.8 cells/mL to 2.8×10^(9) cells∕*** was also evaluated,and the sensors were used to analyze contaminated water samples.A prototype was developed to allow faster,in-situ,and easier analysis avoiding bulky instruments.

关键词： crystal alignment analysis

magnetic,dielectric and electrical modulus of ce^(3+) doped cobalt-magnesium ferrite nanoparticles

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Journal of Rare Earths 2024年第2期42卷 373-382,I0005页

作者： n.m.Basfer Hanaa Almaghamsi Department of Physics Umm AL-Qura UniversityMakkahSaudi Arabia Physics Department College of Science and ArtKing Abdulaziz UniversityPOB344Rabigh291Saudi Arabi

In this work,the magnetic,dielectric properties and electric modulus of ce^(3+) substituted cobaltmagnesium(co_(0.7)mg_(0.3)ce_(x)Fe_(2-x)O_4)(labeled as cmcF) ferrite nanoparticles were investigated in *** magnetization decreases from 50.05 to 34.87 emu/g for further substituting ce^(3+) ***,coercivity increases from 738.22 Gs for the cmcFO sample to 912.10 Gs for the cmcF2 sample,then decreases monotonically to 762.1 Gs for the cmcF5 *** cerium content and particle size play important roles in controlling the magnetization and coercivity of the cmcF *** cmcF nanoferrites are suitable for microwave applications since their high-frequency response ranges from 7.72 to 11.07 *** cmcF nanoferrites' dielectric parameter dispersion exhibits normal *** pristine co-mg nanoferrite only has ε' value of 28.25,but the nanoferrite mcmF2 has ε' value of365.03,with an enhancing ratio of 1192%.The conduction mechanism of the mcmF nanoferrites was determined by fitting the σ_(ac) results via the Jonscher power *** 653 K,large polaron tunnelling is thought to be responsible for this conduction process,which is followed by electron barrier hopping at higher ***-cole diagrams at different temperatures,assuring the contributions of the grains and their boundaries at lower temperatures(653 K) and only the grains at higher *** on our results,the cmcF nanoferrites hold magnetic and semiconducting nature,which can be used in magnetic devices and dielectrics in lower-frequencies or conductors in higher-frequencies.

关键词： nanoferrites Rare earth ions magnetic properties Dielectric parameters Impedance spectroscopy

Early Phases of Star Formation: Testing chemical Tools

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Research in Astronomy and Astrophysics 2024年第1期24卷 96-118页

作者： n.c.martinez S.Paron cOnIcET-Universidad de Buenos Aires.Instituto de Astronomía y Física del Espacio Ciudad Universitaria(C1428EGA)Ciudad Autónoma de Buenos AiresArgentina

Star-forming processes strongly influence the ISm ***,many high-quality databases are available at millimeter *** them,it is possible to carry out studies that review and deepen previous *** these studies involve large samples of sources,it is preferred to use direct tools to study the molecular *** the aim of testing these tools such as the use of the Hcn/Hnc ratio as a thermometer,and the use of H^(13)cO^(+),Hc_(3)n,n_(2)H^(+) and c_(2)H as "chemical clocks," we present a molecular line study toward 55 sources representing massive young stellar objects at different evolutionary stages:infrared dark clouds(IRDcs),highmass protostellar objects(HmPOs),hot molecular cores(Hmcs) and ultracompact H II *** found that the use of the Hcn/Hnc ratio as a universal thermometer in the ISm should be taken with care because the Hcn optical depth is a big issue that can affect the ***,this tool should be utilized only after a careful analysis of the Hcn spectrum,checking that no line,neither the main nor the hyperfine ones,presents absorption *** point out that the analysis of the emission of H^(13)cO^(+),Hc_(3)n,n_(2)H^(+) and c_(2)H could be useful to trace and distinguish regions among IRDcs,HmPOs and *** molecular line widths of these four species increase from the IRDc to the Hmc stage,which can be a consequence of the gas dynamics related to the starforming processes taking place in the molecular *** results not only contribute with more statistics,acting as a probe of such chemical tools,useful to obtain information in large samples of sources,but also complement previous works through the analysis of other types of sources.

关键词： stars:formation ISm:molecules ISm:clouds

Imprints of a gravitational wave through the weak field deflection of photons

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chinese Physics c 2024年第8期48卷 240-245页

作者： Reggie c.Pantig Ali Övgün Physics Department Mapúa University658 Muralla St.IntramurosManila 1002Philippines Physics Department Eastern Mediterranean UniversityFamagusta99628 North Cyprusvia Mersin 10Turkiye

In this study,we investigate the novel phenomenon of gravitational lensing experienced by gravitational waves traveling past a Schwarzschild black hole perturbed by a specific,first-order,polar gravitational *** apply the Gauss-Bonnet theorem,finding a topological contribution to the deflection of light rays passing near the black *** demonstrate that the deflection angle can be determined by analyzing a region entirely outside the path of the light ray,leading to a calculation based solely on the parameters of the perturbing wave(Legendre polynomial order,l;frequency,σ).This approach offers a unique perspective on gravitational lensing and expands our understanding of black hole interactions with gravitational waves.

关键词： supermassive black holes gravitational waves chaos weak deflection angle Gauss-Bonnet theorem