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Frontiers of Materials Science 2016年第2期10卷 168-177页

作者： C. Selene CORIA-MONROY Merida SOTELO-LERMA Hailin HU instituto de energias renovables Universidad Nacional Autonoma de Mexico (UNAM) Priv. Xochicalco S/N 62580 Temixco Morelos Mexico Universidad de Sonora Blvd. Luis Encinas y Rosales S/N Col. Centro Hermosillo Sonora Mexico

CdSe is a widely researched material for photovoltaic applications. One of the most important parameters of the synthesis is the pH value, since it determines the kinetics and the mechanism of the reaction and in consequence, the optical and morphological properties of the products. We present the synthesis of CdSe in solution with strict control of pH and the comparison of ammonia and KOH as alkaline sources and diluted HCI as acid medium. CdSe formation was monitored with photoluminescence emission spectra （main peak in 490 nm, bandgap of CdSe nanoparticles）. XRD patterns indicated that CdSe nanoparticles are mainly of cubic structure for ammonia and HCI, but the hexagonal planes appear with KOH. Product yield decreases with pH and also decreases with KOH at constant pH value since ammonia has a double function, as complexing agent and alkaline source. Changes in morphology were observed in SEM images as well with the different alkaline source. The effect of alkaline sources on photovoltaic performance of hybrid organic solar cells with CdSe and poly（3-hexylthio- phene） as active layers was clearly observed, indicating the importance of synthesis conditions on optoelectronic properties of promising semiconductor nanomaterials for solar cell applications.

关键词： CdSe optical properties morphological properties hybrid solar cells

New discriminant-function-based multidimensional discrimination of mid-ocean ridge and oceanic plateau

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Geoscience Frontiers 2020年第5期11卷 1681-1693页

作者： Surendra P.Verma Lorena Diaz-Gonzalez instituto de energias renovables Universidad Nacional Autonoma de MexicoPriv.Xochicalco S/no.Col.CentroApartado Postal 34TemixcoMor62580Mexico Centro de Investigacion en Ciencias Universidad Autonoma de Estado de MorelosCuernavacaMorelos62209Mexico

From a compilation of geochemical data for the discrimination of the tectonic settings of mid-ocean ridge(MOR;3730 samples)and oceanic plateau(OP;3656 samples),we present two new discriminant functions and diagrams obtained from censored multivariate discordant outlier-free datasets.Ten different sets of data(original concentrations as well as isometric log-ratio transformed(ilr)variables;all 10 major(M)elements as well as all 10 major and 6 trace elements MT)were used to evaluate the quality of discrimination from linear discriminant analysis(LDA)and canonical analysis.Two selected multidimensional models ilrM(9 ilr transformed variables of multi-normally distributed 10 major elements)and ilrMT(15 ilr transformed variables of multi-normally distributed combined 10 major and 6 trace elements),considered as the best or most representative(total of5650 samples for ilrM and 2858 for ilrMT),provided percent success values,respectively,of 80.9%for the MOR and 81.1%for the OP(ilrM)and 88.5%for the MOR and 90.1%for the OP(ilrMT).Both processes(log-ratio transformation and multi-normality)rendered the percent success values similar for both groups(MOR and OP).The respective discriminant functions were successfully used for four tests from known tectonic settings and four application cases(two for ophiolites and two for Precambrian rocks),documenting thus the utility of the new discrimination procedure for the MOR and OP tectonic settings.Furthermore,we showed that our multidimensional procedure is robust against analytical errors or uncertainties,as well as post-emplacement compositional changes caused by element mobility from both low or high temperature alteration.The robustness against the gain or loss of a single element at a time was also documented,from which the ilrMT model was evaluated as more robust than the ilrM model.A new online computer program MOROPdisc was written in Java Framework ZK,which is freely available for use at our web portal http://tlaloc.***.unam.mx.

关键词： MORB Multivariate discordant outliers Log-ratio transformation Multidimensional discrimination Analytical uncertainties Post-emplacement changes

Physical activation of graphene: An effective, simple and clean procedure for obtaining microporous graphene for high-performance Li/S batteries

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Nano Research 2019年第4期12卷 759-766页

作者： Almudena Benitez Alvaro Caballero Julian Morales Jusef Hassoun Enrique Rodriguez-Castellon Jesus Canales-Vazquez Dpto. Quimica Inorganica e Ingenieria Qutmica Instituto de Quimica Fina y Nanoquimica Universidad de Cordoba 14071 Cordoba Spain departm ent of Chemical and Pharmaceutical Sciences University of Ferrara Via Fossato di Mortara 17 44121 Ferrara Italy Dpto. de Quimica Inorganica Cristalografia y Mineralogia Facultad de Ciencias Universidad de Malaga 29071 Malaga Spain instituto de energias renovables Universidad de Castilla-La Mancha Paseo de La Investigacion 1 Albacete 02071 Spain

Graphe ne nano sheets are a promising scaffold to accommodate S for achievi ng high performa nee Li/S battery. Nano sheet activation is used as a viable strategy to induce a micropore system and further improve the battery performance. Accordingly, chemical activation methods dominate despite the need of multiple stages, which slow down the process in addition to making them tiresome. Here, a three-dimensional (3D) N-doped graphene specimen was physically activated with CO2, a clean and single step process, and used for the preparation of a sulfur composite (A-3DNG/S). The A-3DNG/S composite exhibited outstanding electrochemical properties such as an excellent rate capability (1,000 mAh·g^-1 at 2C), high reversible capacity and cycling stability (average capacity ~ 800 mAh·g^-1 at 1C after 200 cycles), values which exceed those measured in chemically activated graphene. Therefore, these results support the use of physical activation as a simple and efficient alternative to improve the performance of carbons as an S host for high-performance Li-S batteries.

关键词： physical activation 3D-graphene solvothermal microwave synthesis Li-S battery

Small-signal Model for Dual-active-bridge Converter Considering Total Elimination of Reactive Current

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Journal of Modern Power Systems and Clean Energy 2021年第2期9卷 450-458页

作者： Juan Ramon Rodriguez-Rodriguez Nadia Maria Salgado-Herrera Jacinto Torres-Jimenez Nestor Gonzalez-Cabrera David Granados-Lieberman Martin Valtierra-Rodriguez the Universidad Nacional Autonoma de Mexico Facultad de IngenieriaDepto.Energia Electri-ca.Av.Universidad 3000Col.UNAM CUCoyoacanCDMXMexico the instituto de energias renovables Universidad Nacional Autonoma de MexicoPriv.Xochicalco s/nCol.Centro.TemixcoMorelosMexico the instituto Tec-nologico Superior de Irapuato Carretera Irapuato-Silao km 12.5.IrapuatoGuanajuatoMexico the Universidad Autonoma de Queretaro Campus San Juan del RioRio Moctezuma 249San Juan del RioQueretaroMexico

Emerging technologies such as electric vehicles,solid-state transformers,and DC transformers are implemented using the closed-loop bi-directional dual-active-bridge(DAB)converter.In this context,it is necessary to have average models that provide an efficient way of tuning the proportional integral(PI)compensator parameters for large-and small-signal applications.We present a novel small-signal model(SSM)for DAB converter with a single closed-loop PI controller and the total elimination of reactive current(IQ=0).The method applies a modulation technique for IQ=0 and introduces a composite function in the controller while reducing the original nonlinear switching model,which allows to decrease the order of the transfer function and analyze the closed-loop operation.The proposed SSM is analyzed using different response time,load,and DC voltage changes.The simulation and experimental results demonstrate the ease of implementation and effectiveness of the proposed model with respect to other SSM techniques.

关键词： Small-signal model(SSM) dual-active-bridge(DAB)converter reactive current elimination proportional integral(PI)control

Polariton polarization rectifier

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Light(Science & Applications) 2019年第1期8卷 505-514页

作者： Evgeny S.Sedov Yuri G.Rubo Alexey V.Kavokin Westlake University 18 Shilongshan RoadHangzhou 310024 Zhejiang ProvinceChina Institute of Natural Sciences Westlake Institute for Advanced Study18 Shilongshan RoadHangzhou 310024 Zhejiang ProvinceChina Vladimir State University Gorky str.87Vladimir 600000Russia instituto de energias renovables Universidad Nacional Autonoma de Mexico62580 TemixcoMORMexico Spin Optics Laboratory Saint Petersburg State University1 UlianovskayaSt.Petersburg 198504Russia

We propose a novel photonic device,the polariton polarization rectifier,intended to transform polariton pulses with arbitrary polarization into linearly polarized pulses with controllable orientation of the polarization plane.It is based on the interplay between the orbital motion of the polariton wave packet and the dynamics of the polariton pseudospin governed by the spatially dependent effective magnetic field.The latter is controlled by the TE-TM splitting in a harmonic trap.We show that the unpolarized polariton pulse acquires linear polarization in the course of propagation in a harmonic trap.This gives the considered structure an extra function as a linear polarizer of polariton pulses.

关键词： field polarized harmonic

Wind Energy Generation Potential in Union Hidalgo, Mexico： A Preliminary Study

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Journal of Energy and Power Engineering 2011年第2期5卷 149-154页

作者： J.R. Dorrego O. Lastres A. Nunez G. Hernfindez U. Miranda R. Saldana instituto de Estudio de la Energia de la Universidad del ISTMO Tehuantepec Oaxaca Alkxico Centro de Investigacion en Energia UNAM Temixeo Morelos Mexico Gerencia de energias No Conveneionales Instituto de Investigaciones Electricas Reforma 113 Col. Palmira Cuernavaca Morelos C. P. 62490

Union Hidalgo municipality in Oaxaca State, Mexico, is located in an area with attractive wind potential. For this reason, this paper presents a preliminary study of the technical feasibility of wind power generation in Union Hidalgo, by a micro-study with a higher resolution than that used in Wind Resource Atlas of Oaxaca, published in April 2004. In this work, the wind map of Union Hidalgo was generated using the micro-scale model WAsP 9.1, with a resolution of 50 meters. Wind speed and direction data recorded at 15 m and 32 m agl (above ground level) over four years and seven months in a surface anemometer station were used. With Class 7 wind patterns, the results show values that justify the installation of wind turbines to produce electricity in the area. Estimated capacity factors (55% on average) are comparable with those obtained in wind power plants already operating in areas near Union Hidalgo and sites with high wind potential in other parts of the world. The topography of the study area is predominantly flat, and together with the directional behavior of the wind, which comes from the NNW 44% of the time, this favors the introduction of wind power plants in the area.

关键词：风力发电厂墨西哥联盟风能资源风力涡轮机微观尺度联合集团数据记录

Analysis of heterogeneous characteristics in a geothermal area with low permeability and high temperature

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Geoscience Frontiers 2017年第5期8卷 1039-1050页

作者： Alfonso Aragón-Aguilar Georgina Izquierdo-Montalvo Siomara López-Blanco Víctor Arellano-Gómez instituto Nacional de Electricidad y Energías Limpias Reforma 113 Col.Palmira Cuernavaca Morelos CP 62490 Mexico

An analytical methodology for reservoir characterization was applied in the central and southwestern zones of Los Humeros geothermal field(LHGF). This study involves analysis of temperature, pressure,enthalpy and permeability in wells and their distribution along the area. The wells located in the central western side of the geothermal field are productive, whereas those located at the central-eastern side are non-productive. Through temperature profiles, determined at steady state in the analyzed wells, it was observed that at bottom conditions(approximately 2300 m depth), temperatures vary between 280 and360℃. The temperatures are higher at the eastern side of central zone of LHGF. A review of transient pressure tests, laboratory measurements of core samples, and correlation of circulation losses during drilling suggest that permeability of the formation is low. The enthalpy behavior in productive wells shows a tendency of increase in the steam fraction. It was found that productivity behavior has inverse relation with permeability of rock formation. Further, it is observed that an imbalance exists between exploitation and recharge. It is concluded from the results that the wells located at central-eastern area have low permeability and high temperature, which indicates possibility of heat storage.

关键词： Los Humeros geothermal field Reservoir performance Hot rock Enthalpy Permeability Recharge

Analysis of the Performance of Optical Code-Division Multiple-Access System(OCDMA),Operating with Gold Codes under Nonlinear Effects

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Journal of Electromagnetic Analysis and Applications 2013年第2期5卷 49-57页

作者： Glendo de Freitas Guimaraes Agliberto Melo Bastos Alisson da Conceicao Ferreira Alex Sander Barros Queiroz Jose Wally Mendonca Menezes Jose Rubens Rodrigues de Sousa Antonio Sergio Bezerra Sombra Laboratorio de Telecomunicacoes e Ciencia e Engenharia dos Materiais(LOCEM) Departamento de FisicaUniversidade Federal do Ceara(UFC)FortalezaBrazil Laboratorio Especializado em Sistema de Telecomunicacoes e Ensino(LESTE) Departamento de TelematicaInstituto Federal do Ceara(IFCE)Campus FortalezaFortalezaBrazil Grupo de Fisica Aplicada e Docencia(GFAD) Instituto Federal do Ceara(IFCE)Campus SobralSobralBrazil departamento de Engenharia de Teleinformatica(deTI) Centro de TecnologiaUniversidade Federal do Ceara(UFC)FortalezaBrazil departamento de Engenharia de energias Universidade da Integracao Internacional da Lusofonia Afro-Brasileira(UNILAB)RedencaoBrazil

A numerical simulation study of the performance of encoding and decoding of short optical pulse in OCDMA (Optical Code Division Multiple Access) systems under non-linear optical effects is presented. The performance of encoding and decoding short pulses is obtained through use of device FBG (fiber Bragg grating) where the codes are inserted through discrete jumps in the optical phase (±π). The multiuser interference is also the object of the present study, where a figure of merit (interference figure) is used to quantify the interference in multiuser auto and cross correlation. We evaluate the dependence of the multiuser interference for the coupling constant of FBG. Finally, the interference inserted in the autocorrelation due to nonlinear effects generated in the nonlinear switching of the coded pulse in a dual core nonlinear directional coupler is examined, where temporal broadening of pulses decoded is observed.

关键词： Fiber Bragg Grating Gold Code OCDMA All-Optical Digital Processing of Signals

R&D of back-end electronics for improved resistive plate chambers for the phase 2 upgrade of the CMS end-capmuon system

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Radiation detection Technology and Methods 2022年第3期6卷 306-316页

作者： H.Kou Z.-A.Liu J.Zhao J.Song Q.Hou W.Diao P.Cao W.Gong N.Wang A.Samalan M.Tytgat M.El Sawy G.A.Alves F.Marujo E.A.Coelho F.Torres Da Silva de Araujo E.M.Da Costa H.Nogima A.Santoro S.Fonseca de Souza D.de Jesus Damiao M.Thiel M.Barroso Ferreira Filho K.Mota Amarilo A.Aleksandrov R.Hadjiiska P.Iaydjiev M.Rodozov M.Shopova G.Sultanov A.Dimitrov L.Litov B.Pavlov P.Petkov A.Petrov E.Shumka S.J.Qian C.Avila D.Barbosa A.Cabrera A.Florez J.Fraga J.Reyes Y.Assran M.A.Mahmoud Y.Mohammed I.Laktineh G.Grenier M.Gouzevitch L.Mirabito K.Shchablo C.Combaret W.Tromeur G.Galbit A.Luciol X.Chen I.Bagaturia I.Lomidze Z.Tsamalaidze V.Amoozegar B.Boghrati M.Ebraimi E.Zareian M.Mohammadi Najafabadi M.Abbrescia G.Iaselli G.Pugliese F.Loddo N.de Filippis R.Aly D.Ramos W.Elmetenawee S.Leszki I.Margjeka D.Paesani L.Benussi S.Bianco D.Piccolo S.Meola S.Buontempo F.Carnevali L.Lista P.Paolucci F.Fienga A.Braghieri P.Salvini P.Montagna C.Riccardi P.Vitulo E.Asilar J.Choi T.J.Kim S.Y.Choi B.Hong K.S.Lee H.Y.Oh J.Goh I.Yu C.Uribe Estrada I.Pedraza H.Castilla-Valdez R.L.Fernandez A.Sanchez-Hernandez E.Vazquez M.Ramirez-Garcia N.Zaganidis A.Radi H.Hoorani S.Muhammad A.Ahmad I.Asghar M.A.Shah W.A.Khan J.Eysermans I.Crotty on behalf of the CMS Muon Group department of Physics and Astronomy Ghent UniversityProeftuinstraat 869000 GhentBelgium UniversitéLibre de Bruxelles Avenue Franklin Roosevelt50-1050 BruxellesBelgium Centro Brasileiro Pesquisas Fisicas R.Dr.Xavier Sigaud150UrcaRio de JaneiroRio de Janeiro 22290-180Brazil department de Fisica Nuclear e Altas energias Instituto de FisicaUniversidade do Estado do Rio de JaneiroRua Sao Francisco Xavier524Rio de JaneiroRio de Janeiro 20559-900Brazil Bulgarian Academy of Sciences Institute for Nuclear Researches and Nuclear EnergyTzarigradsko Shaussee Boulevard 721784 SofiaBulgaria Faculty of Physics University of Sofia5 James Bourchier Boulevard1164 SofiaBulgaria School of Physics Peking UniversityBeijing 100871China State Key Laboratory of Particle detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences B325Main BuildingNo.19(A)Yuquan RoadShijingshan DistrictBeijing 100049China Universidad de Los Andes Carrera 1No.18A-12BogotáColombia Egyptian Network for High Energy Physics Academy of Scientific Research and Technology101 Kasr El-Einy St.CairoEgypt Suez University SuezCairo RoadElsalam CitySuez 43522Egypt Center for High Energy Physics(CHEP-FU) Faculty of ScienceFayoum UniversityEl-Fayoum 63514Egypt Univ Lyon Univ Claude Bernard Lyon 1CNRS/IN2P3IP2I LyonUMR 582269622 VilleurbanneFrance Georgian Technical University 77 Kostava Str.0175 TbilisiGeorgia School of Particles and Accelerators Institute for Research in Fundamental Sciences(IPM)P.O.Box 19395-5531 TehranIran School of Engineering Damghan UniversityDamghan ***Iran INFN Sezione di BariVia Orabona 470126 BariItaly INFN Laboratori Nazionali di Frascati(LNF)Via Enrico Fermi 4000044 FrascatiItaly INFN Sezione di NapoliComplesso University Monte S.AngeloVia Cintia80126 NapoliItaly Dipartimento di Ingegneria Elettrica e delle Tecnologie dell’Informazione UniversitàDegli Studi di Napoli Federico II80126 NapoliI

Purpose The Large Hadron Collider(LHC)at European Organization for Nuclear Research is planned to be upgraded to the high luminosity LHC.Increasing the luminosity makes muon triggering reliable and ofﬂine reconstruction very challenging.To enhance the redundancy of the Compact Muon Solenoid(CMS)Muon system and resolve the ambiguity of track reconstruction in the forward region,an improved Resistive Plate Chamber(iRPC)with excellent time resolution will be installed in the Phase-2 CMS upgrade.The iRPC will be equipped with Front-End Electronics(FEE),which can perform high-precision time measurements of signals from both ends of the strip.New Back-End Electronics(BEE)need to be researched and developed to provide sophisticated functionalities such as interacting with FEE with shared links for fast,slow control(SC)and data,in addition to trigger primitives(TPs)generation and data acquisition(DAQ).Method The BEE prototype uses a homemade hardware board compatible with the MTCA standard,the back-end board(BEB).BEE interacts with FEE via a bidirectional 4.8 Gbps optical paired-link that integrates clock,data,and control information.The clock and fast/slow control commands are distributed from BEB to the FEE via the downlink.The uplink is used for BEB to receive the time information of the iRPC’sﬁred strips and the responses to the fast/slow control commands.To have a pipelined detector data for clusterﬁnding operation,recover(deMux)the time relationship of which is changed due to the transmission protocol for the continuous incoming MUXed data from FEE.Then at each bunch crossing(BX),clusteringﬁred strips that satisfy time and spatial constraints to generate TPs.Both incoming raw MUXed detector data and TPs in a time window and latency based on the trigger signal are read out to the DAQ system.Gigabit Ethernet(GbE)of SiTCP and commercial 10-GbE are used as link standards for SC and DAQ,respectively,for the BEB to interact with the server.Results The joint test results of the BEB with iRPC and Front-End Board(FEB)show a

关键词： CMS iRPC BEE TP DAQ SC

Carbon Burial in Young Tropical Reservoirs Is Higher at Lower Latitudes*

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Journal of Geoscience and Environment Protection 2021年第12期9卷 84-99页

作者： Elizabeth Sikar Marco Aurelio dos Santos Ana Carolina Moterani Isabella Matvienko Ana Carla Martins Veras Juliana Pinto Pereira Dias Orleno Marques da Silva Junior Claudio Pavani Marcelo Amorim Teodosio das Neves Milisse Nzualo Ayr Manoel Portilho Bentes Junior Rogerio Duarte Construmaq Sã o Carlos S&#227 o Carlos SP Brazil Programa de Planejamento Energético da Universidade Federal do Rio de Janeiro Brazil Laboratório de energias Renováveis e Estudos Ambientais da Universidade Federal do Rio de Janeiro Brazil instituto de Pesquisas Científicas e Tecnológicas do Estado do Amapá Brazil Programa de Pós-Graduaç ã o em Geografia da Universidade Federal do Amapá Brazil

Man-made environments such as tropical hydroelectric reservoirs alter the preexisting carbon (C) cycle and remove C from circulation through burial in sediments. Carbon burial (CB) was measured using the silica-tracer method during four field surveys in the less than six-year-old Belo Monte tropical reservoir. Fresh C sedimentation was also measured. Belo Monte’s CB median rate 276 (n = 84;min 0;max 352,625 mg C·m-2·d-1) is within the range (230 to 436 mg C·m-2·d-1) of CB rates measured further downstream at the Xingu Ria and higher than the averaged over 50 years oceanic rate 244 mg C·m-2·d

关键词： Carbon Burial Sediments Hydroelectric Reservoirs