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Soil resilience assessment using soil profile descriptions and Analytic Hierarchy Process in Mediterranean mountains considering diverse fire occurrences

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Journal of Mountain Science 2024年第8期21卷 2517-2532页

作者： Jesús RODRIGO-COMINO departamento de Análisis Geográfico Regional y Geografía física Facultad de Filosofía y LetrasCampus Universitario de CartujaUniversidad de GranadaGranada 18071Spain

Wildfires are complex natural phenomena that exert significant impacts on landscapes,societies,and *** the concept of resilience is crucial in mitigating its possible negative impacts,as it involves preparing for,responding to,and recovering from *** research aims to demonstrate the utility of in situ soil profile description in assessing land use resilience using an Analytic Hierarchy Process(AHP)through an expert panel *** study examines a catchment located in the Balearic Islands,considering two fire occurrences(once and twice),comparing abandoned agricultural terraces and natural *** results demonstrated that the priority ranking of variables to assess soil profile resilience against wildfires,determined by a panel of 10 experts,identified horizon depth(25.1%),slope inclination(21.5%),and hydrological connectivity(16.6%)as the most crucial *** variables,such as number and size of roots,structure of pedal soil material,size class structure,and rock fragments,also contributed to resilience but to a lesser extent,with scores ranging from 5.7%to 9.6%.Analyzing the priorities established by the experts using AHP,the results showed that the least resilient soil horizon was H1 of the control hillslope,especially under high and low connectivity processes,which aligned with the loss of superficial soil horizons after one and two *** showed greater changes in resilience after occurring wildfires compared to terraces,with the most significant alterations occurring after the second wildfire *** study addresses a significant knowledge gap in the field by highlighting the interconnectedness of wildfires,resilience,and land use,providing insights into land management strategies for wildfire-prone regions.

关键词： Soil profiles Soil geography Wildfires AHP Land management Expert panel survey

Low-power SiPM readout BETA ASIC for space applications

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Nuclear Science and Techniques 2024年第3期35卷 153-169页

作者： Anand Sanmukh Sergio Gómez Albert Comerma Joan Mauricio Rafel Manera Andreu Sanuy Daniel Guberman Roger Catala Albert Espinya Marina Orta Oscar de la Torre David Gascon departament de física Quàntica i Astrofísica(fQA) Institut de Ciències del Cosmos(ICCUB)Universitat de Barcelona(UB)08028 BarcelonaSpain Institut d’Estudis Espacials de Catalunya(IEEC) 08034 BarcelonaSpain Electronics department Serra Hunter fellow at Polytechnic University of Catalonia(UPC)08019 BarcelonaSpain

The BETA application-specific integrated circuit(ASIC)is a fully programmable chip designed to amplify,shape and digitize the signal of up to 64 Silicon photomultiplier(SiPM)channels,with a power consumption of approximately~1 mW/*** to its dual-path gain,the BETA chip is capable of resolving single photoelectrons(phes)with a signal-to-noise ratio(SNR)>5 while simultaneously achieving a dynamic range of~4000 ***,BETA can provide a cost-effective solution for the readout of SiPMs in space missions and other applications with a maximum rate below 10 *** this study,we describe the key characteristics of the BETA ASIC and present an evaluation of the performance of its 16-channel version,which is implemented using 130 nm *** ASIC also contains two discriminators that can provide trigger signals with a time jitter down to 400 ps fWHM for 10 *** linearity error of the charge gain measurement was less than 2%for a dynamic range as large as 15 bits.

关键词： Radiation detectors Silicon photomultipliers Photon sensors front-end electronics Mixed-mode ASICs Space technology

Stress tensors and quantification of fracture patterns to analyze connectivity and potential fluid flow in a mesa landform of the Northern Andes

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Journal of Mountain Science 2024年第1期21卷 271-291页

作者： GARCÍA-ARIAS Sergio VELANDIA francisco ALVAREZ Angélica SANABRIA-GÓMEZ JoséD TARAZONA Yessenia VARGAS María Camila Escuela de Geología Universidad Industrial de SantanderCra.27 Calle 9BucaramangaColombia Escuela de física Universidad Industrial de SantanderCra.27 Calle 9BucaramangaColombia

This work applies stress tensors inversions and quantification of fracture patterns along the Mesa de Los Santos, in the Eastern Cordillera of Colombia, to better understand the potential fluid flow. It thus contributes to the conceptual hydrogeological model. The area was subdivided into three blocks, separated by the NW Potreros and the Los Santos faults, having minor inner faults of different orientations. This separation facilitates the analysis of the fractures measured in the field, which in general show high dip angles and a conjugate geometry in the northern block, tension fractures(Mode I) in the central block, and a random distribution in the southwestern block. WinTensor treatment of slickensides yielded a maximum horizontal stress(SHmax) of 111o, which coincides with the WNW-ESE tensor observed from the conjugate and tension joints. We then used frac Pa Q to generate interpolation maps of fracture intensity and density. The maps show the highest values in the central block and the lowest in the northern block,where the precipitation is higher, causing intensive rock weathering and homogenization of the fracture planes. Although the highest values of connectivity by line are found to the south of the mesa, we suggest the possibility of greater flow from the recharge zone(NE) along bedding planes and open NW-SE fractures.

关键词： Mesa de Los Santos Colombia Win-Tensor fracPaQ Strike-slip faults fractured aquifers

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

Experimental implementation of phase triplicator gratings in a spatial light modulator

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Chinese Optics Letters 2024年第2期22卷 64-69页

作者：高尚 María del Mar Sánchez-López Ignacio Moreno Instituto de Bioingeniería Universidad Miguel HernándezElche 03202Spain departamento de física Aplicada Universidad Miguel HernándezElche 03202Spain departamento de Ciencia de Materiales Óptica y Tec.Electr´onicaUniversidad Miguel HernándezElche 03202Spain

In this work,we compare different methods for implementing a triplicator,a phase grating that generates three equiintense diffraction *** design with optimal efficiency features a continuous phase profile,which cannot be easily reproduced,and is typically affected by *** compare its performance with binary and sinusoidal phase *** also analyze the effect of quantizing the phase ***,a random approach is adopted to eliminate the additional harmonic *** all cases,a liquid-crystal-on-silicon spatial light modulator is employed to experimentally verify and compare the different approaches.

关键词： diffraction gratings phase modulation triplicator spatial light modulators

Observation about the Classical Electromagnetic Gauge Transformation and Its Quantum Correspondence

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Journal of Modern Physics 2024年第4期15卷 474-479页

作者： Gustavo V. López Jorge A. Lizarraga departamento de física Universidad de Guadalajara Guadalajara Mexico

Using the Landau and symmetric gauges for the vector potential of a constant magnetic field and the quantum problem of a charged particle moving on a flat surface, we show the classical electromagnetic gauge transformation does not correspond to a one-dimensional unitary group transformation U(1) of the wave function for the quantum case. In addition, with the re-examination of the relation between the magnetic field B and its vector potential A, we found that, in order to have a consistent formulation of the dynamics of the charged particle with both expressions, we must have that B=∇×A if and only if B≠0.

关键词： Gauge Transformation Harmonic Oscillator Quantum Hall Effect Electromagnetic Potentials

Metal-modulated epitaxy of Mg-doped Al_(0.80)In_(0.20)N-based layer for application as the electron blocking layer in deep ultraviolet light-emitting diodes

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Journal of Semiconductors 2024年第5期45卷 80-89页

作者： Horacio Irán Solís-Cisneros Carlos Alberto Hernández-Gutiérrez Enrique Campos-González Máximo López-López Optomechatronics Group Tecnológico Nacional de México Campus Tuxtla Gutiérrezcarretera Panamericana 1080C.P.29050Tuxtla GutiérrezChiapasMéxico departamento de física Instituto Nacional de Investigaciones NuclearesCarretera México-Toluca s/nC.P.52750La Marquesa OcoyoacacMéxico departamento de física Centro de Investigación y estudios Avanzados del Instituto Politécnico NacionalAv.Instituto Politécnico Nacional 2508San Pedro ZacatencoGustavo A.Madero07360 Ciudad de MéxicoCDMXMéxico

This work reports the growth and characterization of p-AlInN layers doped with Mg by plasma-assisted molecular beam epitaxy(PAMBE).AlInN was grown with an Al molar fraction of 0.80 by metal-modulated epitaxy(MME)with a thickness of 180 nm on Si(111)substrates using AlN as buffer *** substrate temperatures were used to enhance the incorporation of indium atoms into the alloy without clustering,as confirmed by X-ray diffraction(XRD).Cathodoluminescence measurements revealed ultraviolet(UV)range ***,Hall effect measurements indicated a maximum hole mobility of 146 cm^(2)/(V∙s),corresponding to a free hole concentration of 1.23×10^(19)cm^(−3).The samples were analyzed by X-ray photoelectron spectroscopy(XPS)estimating the alloy composition and extracting the fermi level by valence band ***-doped AlInN layers were studied for use as the electron-blocking layer(EBL)in LED *** varied the Al composition in the EBL from 0.84 to 0.96 molar fraction to assess its theoretical effects on electroluminescence,carrier concentration,and electric field,using SILVACO *** results from this study highlight the importance and capability of producing high-quality Mg-doped p-AlInN layers through *** simulations suggest that an Al content of 0.86 is optimal for achieving desired outcomes in electroluminescence,carrier concentration,and electric field.

关键词： metal-modulated epitaxy AlInN DUV-LED EBL simulation

High CO_(2)permeation using a new Ce_(0.85)Gd_(0.15)O_(2-δ)-LaNiO_(3)composite ceramic–carbonate dual-phase membrane

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Journal of Environmental Sciences 2024年第6期140卷 219-229页

作者： Daniela González-Varela Jfrancisco Gómez-García Gustavo Tavizon Heriberto Pfeiffer Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCd.UniversitariaDel.CoyoacánCP 04510Ciudad de MéxicoMéxico departamento de física y Química Teórica Facultad de QuímicaUniversidad Nacional Autónoma de MéxicoCd.UniversitariaDel.CoyoacánCP 04510Ciudad de MéxicoMéxico 不详

This work shows the synthesis,characterization and evaluation of dense-ceramic membranes made of Ce_(0.85)Gd_(0.15)O_(2-δ)-LaNiO_(3)(CG-LN)composites,where the fluorite-perovskite ratio(CG:LN)was varied as follows:75:25,80:20 and 85:15 wt.%.Supports were initially characterized by XRD,SEM and electrical conductivity(using vacuum and oxygen atmospheres),to determine the composition,microstructural and ionic-electronic conductivity ***,supports were infiltrated with an eutectic carbonates mixture,producing the corresponding dense dual-phase membranes,in which CO_(2)permeation tests were ***,CO_(2)permeation experiments were performed from 900 to 700℃,in the presence and absence of oxygen(flowed in the sweep membrane side).Results showed that these composites possess high CO_(2)permeation properties,where the O_(2)addition significantly improves the ionic conduction on the sweep membrane ***,the GC80-LN20 composition presented the best results due to the following physicochemical characteristics:high electronic and ionic conductivity,appropriate porosity,interconnected porous channels,as well as thermal and chemical stabilities between the composite support and carbonate phases.

关键词： CO_(2)permeation Doped CeO_(2) LaNiO_(3) Impedance Ceramic carbonate membrane

Close Major-merger Pairs at z=0: Star-forming Galaxies with Pseudobulges

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Research in Astronomy and Astrophysics 2024年第5期24卷 35-60页

作者：何川徐聪 Ute Lisenfeld 戴昱方陶陶黄家声王炜余清正 Chinese Academy of Sciences South America Center for Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China departamento de física Teórica y del Cosmos Universidad de Granada18071 GranadaSpain Instituto Carlos I de física Téorica y Computacional Facultad de Ciencias18071 GranadaSpain department of Astronomy Xiamen UniversityXiamen 361005China CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

We present a study of star-forming galaxies (SfGs) with pseudobulges (bulges with Sérsic index n2σ) mean of specific star formation rate (sSfR) enhancement (sSfR_(enh)=0.33±0.07 versus sSfR_(enh)=0.12±0.06) and br... 详细信息

We present a study of star-forming galaxies (SfGs) with pseudobulges (bulges with Sérsic index nfrom new aperture photometries in the optical and near-infrared bands (aperture size of 7 kpc) and from the literature,we find that the mean Age of central stellar populations in Spirals with pseudobulges is consistent with that of disky galaxies and is nearly constant against the bulge-to-total ratio (B/T).Paired Spirals have a slightly lower fraction of pure disk galaxies (B/T≤0.1) than their counterparts in the control *** to SfGs with classical bulges,those with pseudobulges have a higher (>2σ) mean of specific star formation rate (sSfR) enhancement (sSfR_(enh)=0.33±0.07 versus sSfR_(enh)=0.12±0.06) and broader scatter (by~1 dex).The eight SfGs that have the highest sSfR_(enh)in the sample all have pseudobulges.A majority (69%) of paired SfGs with strong enhancement (having sSfR more than5 times the median of the control galaxies) have *** Spitzer data show that the pseudobulges in these galaxies are tightly linked to nuclear/circum-nuclear *** SfGs in S+S and in S+E pairs have significantly (>3σ) different sSfR enhancement,with the means of sSfR_(enh)=0.45±0.08 and-0.04±*** find a decrease in the sSfR enhancements with the density of the environment for SfGs with *** a high fraction (5/11) of pseudobulge SfGs in S+E pairs are in rich groups/clusters (loca density N_(1Mpc)≥7),the dense environment might be the cause for their low s SfR_(enh).

关键词： galaxies evolution-galaxies interactions-galaxies star formation-galaxies structure-galaxies bulges-galaxies photometry