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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

A review on the parasitic isopod genus notophryxus ***,1883(Crustacea:isopoda),and first report of notophryxus globularis ***,1885 from Lakshadweep Sea(Amini island)

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Acta Oceanologica Sinica 2024年第8期43卷 142-153页

作者： Mukkattu nazar Suhaana Jaime Gómez-gutiérrez Paravanparambil Rajakumar Jayachandran Punnakkal Hari Praved Sivasankaran Bijoy nandan Department of marine Biology Microbiology and BiochemistrySchool of Marine SciencesCochin University of Science and TechnologyKochi-Kerala 682016India Departamento de Plancton y Ecología marina Centro Interdisciplinario de Ciencias MarinasInstituto Politécnico NacionalLa Paz B.C.S.23096Mexico Applied Research Centre for Environment and marine Studies King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia

isopod crustaceans of the family Dajidae are exclusively marine *** genus notophryxus ***,1883 currently includes nine nominal species,which are very rarely reported as the chances for encountering these specimens are *** comprehension of the taxonomy,biology,ecology,and life cycle of species belonging to the notophryxus genus is notably *** nominal species of notophryxus genus are reviewed here to obtain a comprehensive and integrative taxonomic understanding of this genus,in an attempt to address the *** paper also documents the rediscovery of an ectoparasitic isopod from the genus notophryxus in indian waters,after 55 *** isopod specimens obtained from the outer reefs of Amini island in the Lakshadweep archipelago,Southeastern Arabian Sea,display morphological congruence to notophryxus globularis ***,*** only previous report on this species dates back to 1885 from ***'description of *** as an ectoparasite on the euphausiid Thysanoessa gregaria ***,1883 in the north *** discovery represents a range extension of *** from the north Pacific to the Arabian *** cryptoniscid larvae and three adult females of ***(with dwarf males)were found attached to four adult mysid specimens of Siriella aequiremis Hansen,*** present study provides an improved diagnosis of *** with the aid of light microscopy images and line drawings which was not given in the original ***,1885 *** research also provides a concise description of cryptoniscid larvae from the same sampling location and same host which is most likely to be *** larvae.

关键词： Dajiidae Mysid cryptoniscan larvae Southeastern Arabian Sea notophryxus

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

Roller Screw and Threaded Chain Speed Reducer: An Experimental Evaluation

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Modern Mechanical Engineering 2024年第1期14卷 1-11页

作者： Filiberto gutiérrez instituto de ingeniería Universidad Nacional Autónoma de México Mexico City Mexico

We are developing a speed reducer that can be considered a transformation of a worm gear reducer: the worm is replaced by an inverted roller screw, and the gear is replaced by a threaded chain drive. This configuration lessens wear, increases load capacity, and improves efficiency. The threaded chain consists of nut-shaped links. This paper presents the results of tests carried out on a prototype with a reduction ratio of 46.

关键词： Speed Reducer inverted Roller Screw Chain Drive Threaded Chain Drive

THE SUMERiAn TERM u_(8)/ud_(5)/ab_(2)/eme_(3)/_(6)sila_(4)/maš_(2)/amar du_(3)(-a)

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Journal of Ancient Civilizations 2024年第1期39卷 1-28,123页

作者： marcos Such-gutiérrez Facultad de Filosofía y Letras Universidad Autónoma de Madrid

The aim of the present article is twofold:firstly,to prove that the expression animal+young du_(3)(-a),which is basically documented in texts from the 3rd millennium BC,refers to a dam that has just given birth,and se... 详细信息

关键词： 3rd millennium BC female animal+young du_(3)(-a) livestock newborn suckling animal UrⅢperiod

The Effect of Water and Salt Stress on Paspalum dilatatum,a Constituent of Pampas natural Grasslands

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Phyton-international Journal of Experimental Botany 2024年第8期93卷 2009-2018页

作者： Claudia A.Porcelli Gerardo Rubio Flavio H.gutiérrez Boem Raul S.Lavado Departamento de Química Facultad de AgronomíaUniversidad de Buenos AiresBuenos AiresC1417DSEArgentina instituto de investigaciones en Biociencias Agricolas y Ambientales(inBA) Facultad de AgronomíaUniversidad de Buenos AiresBuenos AiresC1417DSEArgentina

The effects of the salt stress on plant growth are usually increased by the water *** studied the impact of both stresses in simultaneous pulses of drought and salinity on Paspalum *** forage species is native to South America,spread in grasslands in many tropical,subtropical,and temperate areas of the world,and very common in grasslands of the Flooding Pampas of *** what happens in *** compared a pot experiment,a non-stressed control against water stress for a month(midpoint between field capacity and wilting point),and two saline stresses(moderate,6 d·Sm^(−1)and strong,12 d·Sm^(−1)),also for a *** biomass(green leaf;non-leaf green material,and dry material)and roots were harvested,weighed,and analyzed for nitrogen,phosphorus,and *** biomass of all components significantly decreased when both stresses were *** plus strong saline stress reduced by half the total biomasses,compared to the *** proportion of aerial biomass/root biomass ratio as well as aerial green component/dry materials ratio tend to decrease when subjected to both *** concentration in plants was not significantly affected,but phosphorus concentration increased in aerial biomass components,from 0.10 to 0.18 mg·kg^(−1)between the extreme treatments,but did not change in *** concentration in plants increased(i.e.,in green leave sodium(na)increased from 0.27 to 2.01 mg·kg^(−1)between the extreme treatments),whereas other cations either did not change or decreased,affecting the ratios between *** performance allows us to infer that the na accumulation of *** behaves in an intermediate range,compared to very tolerant to salts or non-salt tolerant species of the Paspalum *** agreement,when salts were applied in the form of a pulse,*** tolerated higher salinity than that found by other authors for the same species,using continuous salinity.

关键词： Dallis grass salinity drought sodium in plants phosphorus in plants potassium/sodium ratio

Clinical features of chronic kidney disease in dogs with the serological presence of Leptospira spp.,Ehrlichia canis,and Anaplasma phagocytophilum

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Animal Diseases 2024年第3期4卷 224-230页

作者： Claire A.Vázquez‑Manzanilla maría F.Cárdenas‑marrufo Eduardo gutiérrez‑Blanco Matilde Jiménez‑Coello nelly R.Pech‑Sosa Antonio Ortega‑Pacheco Departamento de Salud Animal y Medicina Preventiva Facultad de Medicina Veterinaria y ZootecniaCampus de Ciencias Biológicas y AgropecuariasUniversidad Autónoma de YucatánMéridaYucatán 97100México Unidad interinstitucional de investigación Clínica y Epidemiológica Facultad de MedicinaUniversidad Autónoma de YucatánMéridaYucatán 97000México

Chronic kidney disease is commonly diagnosed in dogs,and clinical signs may be aggravated when infected agents are *** this case report,33 dogs with chronic kidney disease were clinically evaluated and serologically tested for Leptospira spp.,Ehrlichia canis,and Anaplasma *** seroprevalence for Leptospira *** 39.4%.The most frequent serovars found were Pyrogenes,Canicola,Bratislava and Australis,with serological titers between 1:100 to 1:*** signs included fever,depression,decreased body condition,vomiting and hema‑*** laboratory fndings were anemia,leukocytosis,thrombocytopenia,increased liver enzymes,urea and creatinine,hyperbilirubinemia and *** leptospira seronegative dogs were positive for one or both monitored homoparasites(i.e.,*** and ***);only three leptospira seropositive dogs were positive for one or both *** also suggest that endemic hemoparasites of dogs should be moni‑tored in dogs with a kidney condition for a better clinical picture of the patients and therapeutic approach.

关键词： Anaplasma Chronic kidney disease Dog Ehrlichia Leptospira

Brillouin expanded time-domain analysis based on dual optical frequency combs

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Light(Science & Applications) 2024年第8期13卷 1534-1544页

作者： Jae Hyeong Youn Kwang Yong Song Sonia martin-Lopez Miguel Gonzalez-Herraez maría R.Fernández-ruiz Dept.of Physics Chung-Ang UniversitySeoulKorea Dept.of Electronics Universidad de AlcaláMadridSpain

Brillouin Optical Time-Domain Analysis(BOTDA)is a widely-used distributed optical fiber sensing technology employing pulse-modulated pump waves for local information retrieval of the Brillouin gain or loss *** spatial resolution of BOTDA systems is intrinsically linked to pulse duration,so high-resolution measurements demand high electronic bandwidths inversely proportional to the *** paper introduces Brillouin Expanded Time-Domain Analysis(BETDA)as a modified BOTDA system,simultaneously achieving high spatial resolution and low detection *** two optical frequency combs(OFCs)with different frequency intervals as pump and probe,local Brillouin gain spectra are recorded by their spectral beating traces in an expanded time domain.A 2-cm-long hotspot located in a 230m single-mode fiber is successfully measured in the time domain with a detection bandwidth of less than 100 kHz using dual OFCs with tailored spectral phase,line spacing,and bandwidth.

关键词： pump optical fiber

Calibration of the DEM sliding friction and rolling friction parameters of a cohesionless bulk material

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Particuology 2024年第9期92卷 126-139页

作者： Jonatan marín Pérez Tugrul Comlekci Yevgen Gorash Donald MacKenzie University of Strathclyde 75 Montrose StreetG11XJGlasgowUnited Kingdom

The discrete element method(DEM)has become a valuable tool for understanding the mechanical behaviour of granular assemblies,however,the accuracy of the DEM simulations depends on several interaction parameters such as the sliding friction and rolling friction ***,these parameters are estimated using bulk calibration approach(BCA)where the draw down test has been suggested as an effective way to approach these *** test provides up to four bulk criteria,the angle of repose,shear angle,mass flow rate and the mass loss which are used to narrow down the possible ***,there is still more research needed around it to fully understand how this methodology *** experimental and numerical study was carried out using the draw down test to assess the influence of different mass flow rates and particle shapes on DEM parameters for a cohesionless bulk *** is concluded that use of multi-sphere particles and three aperture sizes in the draw down test to calibrate the sliding and rolling friction parameters of a cohesionless bulk material can converge to a small feasible region in which a single combination of the friction coefficients can be *** calibrated sliding and rolling friction coefficients were validated using multi-sphere particles,where the maximum deviation was 5.9%from the experimental values.

关键词： Discrete element method Calibration Draw down Sliding friction Rolling friction Particle shape