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求解LOPLACE问题的新方法——预估跳跃法

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华北理工大学学报(自然科学版) 1987年第3期 86-92页

作者： j.M.Vega—Fernandz j.F.Dugue—Carrillo j.j.pena—Eernal 宋庆功

本文提出了一个求解Laplace方程的新方法——预估跳跃法,它使求解过程加快。并且将用此法求得的一些结果与用传统方法求解的结果进行了比较。

关键词： SOR 跳跃法方程 LOPLACE

Synthesis of coral-like structures of Pr-Yb co-doped YIG: Structural,optical, magnetic and antimicrobial properties

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journal of Rare Earths 2024年第3期42卷 543-554,I0004页

作者： A.Fernandez Francisca P.Araujo Y.Guerra S.Castro-Lopes j.Matilla-Arias Idglan S.de Lima Edson C.Silva-Filho josy A.Osajima F.Guerrero R.pena-Garcia Federal University of Piau Graduate Program in Materials Science and EngineeringTeresinaPIBrazil Federal Rural University of Pernambuco Academic Unit of Cabo de Santo AgostinhoCabo de Santo AgostinhoPEBrazil Federal University of Piaui Department of PhysicTeresinaPBrazil Federal University of Pernambuco Graduate Program in Materials ScienceRecifePEBrazil University of Granma Departmentof Basic Sciences and Applied InformaticsFaculty of Technical SciencesBayamoCuba Federal University of Amazonas Department of PhysicManausAMBrazil Federal University of Pernambuco Department of PhysicRecifePEBrazil

Coral-like structures of the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12),(0.00 ≤ x ≤ 0.04, 0.00 ≤ y ≤ 0.02) compound were synthesized using the sol-gel method. Structural investigation certified the YIG cubic crystal structure formation, without any secondary phase. It is shown that, the relatively large ionic radius of the dopant cations results in an expansion of the lattice parameter, variations in the Iona-O-Iondangle, Iona-O,Iond-O and Ionc-O bond distances and decrease in the average crystallite size. Fourier transform infrared(FTIR) and Raman measurements are essential to testify the single-phase formation of YIG crystal structure and are observed changes in the stretching and vibrational modes, respectively. The morphological study, energy dispersive spectroscopy(EDS) spectra and textural properties show corallike structures, peaks associated with Pr^(3+) and Yb^(3+) atoms and the effect of dopants on surface area,diameter, and pore volume, respectively. The optical analysis from diffuse reflectance spectra witnessed an increase in the optical gap band, a decrease in Urbach energy and blue shift in the charge transfer,correlated with the expansion of the unit cell due to the dopant's insertion in the YIG structure. A typical ferrimagnetic behavior is exhibited by the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12)compound. The saturation magnetization(M_(s)), cubic anisotropy constant(K_(1)) and coercive field(H_(c)) increase with the Pr^(3+)cations content, as consequence of their magnetic nature and distribution around of Fe^(3+)ions due to the coexistence with the Yb^(3+). Finally, for the first time, antibacterial tests by mean of the direct contact method were performed for YIG co-doped with Pr^(3+)and Yb^(3+)and it is shown that, relatively high dosages of Pr^(3+) cations favored the activity against S. aureus, therefore, a new biological property for YIG doped with rare earths is presented.

关键词： Yttrium iron garnet(YIG) Coral-like structures Rare earths Band gap energy Magnetic properties Antimicrobial properties

Step‑by‑Step Modulation of Crystalline Features and Exciton Kinetics for 19.2%Efficiency Ortho‑Xylene Processed Organic Solar Cells

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Nano-Micro Letters 2024年第2期16卷 258-272页

作者： Bosen Zou Weiwei Wu Top Archie Dela pena Ruijie Ma Yongmin Luo Yulong Hai Xiyun Xie Mingjie Li Zhenghui Luo jiaying Wu Chuluo Yang Gang Li He Yan Department of Chemistry Department of Chemistry and Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction The Hong Kong University of Science and TechnologyClear Water BayHong KongPeople’s Republic of China Department of Electronic and Information Engineering Research Institute for Smart Energy(RISE)Guangdong‑Hong Kong‑Macao(GHM)Joint Laboratory for Photonic‑Thermal‑Electrical Energy Materials and DevicesThe Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077People’s Republic of China The Hong Kong University of Science and Technology Function HubAdvanced Materials ThrustNanshaGuangzhou 511400People’s Republic of China Department of Applied Physics The Hong Kong Polytechnic UniversityHong KongPeople’s Republic of China Shenzhen Key Laboratory of New Information Display and Storage Materials College of Materials Science and EngineeringShenzhen UniversityShenzhen 518060People’s Republic of China

With plenty of popular and effective ternary organic solar cells(OSCs)construction strategies proposed and applied,its power conversion efficiencies(PCEs)have come to a new level of over 19%in single-junction ***,previous studies are heavily based in chloroform(CF)leaving behind substantial knowledge deficiencies in understanding the influence of solvent choice when introducing a third ***,we present a case where a newly designed asymmetric small molecular acceptor using fluoro-methoxylated end-group modification strategy,named BTP-BO-3FO with enlarged bandgap,brings different morphological evolution and performance improvement effect on host system PM6:BTP-eC9,processed by CF and ortho-xylene(o-XY).With detailed analyses supported by a series of experiments,the best PCE of 19.24%for green solvent-processed OSCs is found to be a fruit of finely tuned crystalline ordering and general aggregation motif,which furthermore nourishes a favorable charge generation and recombination ***,over 19%PCE can be achieved by replacing spin-coating with blade coating for active layer *** work focuses on understanding the commonly met yet frequently ignored issues when building ternary blends to demonstrate cutting-edge device performance,hence,will be instructive to other ternary OSC works in the future.

关键词： Organic solar cells Ternary design Solvent selection Flouro-methoxylated end group Morphological ordering

Detecting subtle changes in sperm membranes in veterinary andrology

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Asian journal of Andrology 2007年第6期9卷 731-737页

作者： Fernando j. pena Department of Animal Health and Medicine Faculty of Veterinary Medicine University. of Extremadura Cdceres 10071 Spain

Thanks to the increasing use of flow cytometry in research in veterinary spermatology, many new membrane integrity assays have been developed over the past decade. These assays are important because of their superior ability to forecast fertility when compared with other tests, such as sperm motility. This major component of the sperm quality assessment has generated new investigations with the aim of developing tests that can detect membrane damage in a very early state. Using phospholipid transposition tests, early changes in membrane permeability and fluidity can be assessed in a large number of spermatozoa using fluorescent probes in combination with flow cytometry.

关键词： sperm membranes flow cytometry early membrane changes veterinary

Using fireball networks to track more frequent reentries:Falcon 9 upperstage orbit determination from video recordings

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Astrodynamics 2021年第4期5卷 347-358页

作者： Eloy pena-Asensio josep M.Trigo-Rodriguez Marco Langbroek Albert Rimola Antonio j.Robles Departament de Química Universitat Autònoma de Barcelona(UAB)BellaterraCatalonia 08193Spain Institute of Space Sciences(CSIC) Cerdanyola del VallèsBarcelonaCatalonia 08193Spain Institut d’Estudis Espacials de Catalunya(IEEC) Ed.NexusBarcelonaCatalonia 08034Spain Leiden Observatory Faculty of ScienceLeiden University95002300 RA Leidenthe Netherlands Belgian Working Group Satellites(BWGS) Belgium Spanish Meteor Network(SPMN)Team Spain

On February 16,2021,an artificial object moving slowly over the Mediterranean was recorded by the Spanish Meteor Network(SPMN).Based on astrometric measurements,we identified this event as the reentry engine burn of a SpaceX Falcon 9 launch vehicle’s upper *** study this event in detail,we adapted the plane intersection method for near-straight meteoroid trajectories to analyze the slow and curved orbits associated with artificial *** corroborate our results,we approximated the orbital elements of the upper stage using four pieces of“debris”cataloged by the ***’s Combined Space Operations *** on these calculations,we also estimated the possible deorbit hazard zone using the MSISE90 model *** provide guidance regarding the interference that these artificial bolides may generate in fireball ***,because artificial bolides will likely become more frequent in the future,we point out the new role that ground-based detection networks can play in the monitoring of potentially hazardous artificial objects in near-Earth space and in determining the strewn fields of artificial space debris.

关键词： fireball reentry deorbit artificial meteor multistation

Multi-Sectoral Reflections and Efforts in Strengthening Partnerships to Reduce Disaster Risk in Mexico:The First MuSe-IDRiM Conference

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International journal of Disaster Risk Science 2020年第5期11卷 686-691页

作者： Irasema Alcantara-Ayala Daniel Rodriguez-Velazquez Ricardo j Garnica-pena Alejandra Maldonado-Martinez Institute of Geography National Autonomous University of Mexico(UNAM)04510 Mexico CityMexico National School of Social Work.National Autonomous University of Mexico(UNAM) 04510 Mexico CityMexico Disaster Risk Reduction Consultant 04700 Mexico CityMexico

Notwithstanding the high societal impact of disasters in Mexico,there is a lack of integrated efforts to establish a sound policy for reducing disaster risk to counterbalance the existing concentrated endeavors in disaster *** the face of such segmentation,the science and technology community has advocated for a change of perspective,from civil protection to integrated disaster risk *** first Multi-Sectoral Conference towards Integrated Disaster Risk Management in Mexico:Building a National Public Policy(MuSe-IDRiM Conference)was held in Mexico City at National Autonomous University of Mexico,21-24 October *** support of the implementation of the Sendai Framework for Disaster Risk Reduction 2015-2030,the conference aimed at enhancing the dialogue between the scienee and technology community,citizens,civil society organizations,private and public sectors,and the federtil,state,and municipal governments to foster the process of transforming the current National Civil Protection System into a national public policy oriented towards integrated disaster risk management(DRM).Barriers and challenges to the implementation of integrated DRM were *** of integrated DRM challenges current socioeconomic structures and encourages all releva nt stakeholders to think,decide,and act from a different perspective and within and across spatial,temporal,jurisdictional,and institutional *** disaster risk from an integrated approach,learning skills that authorities have not learned or used,and hence,strengthening disaster risk governance are prerequisites to effectively manage disaster risk.

关键词： Disaster risk reduction Integrated disaster risk management Mexico Science-based policy making SINAPROC

Dispersion of niquel on the microstructure in magnesium based alloys for hydrogen storage

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journal of Magnesium and Alloys 2013年第4期1卷 292-296页

作者： A.A.Zaldıvar-Cadena I.Dıaz-pena j.G.Cabanas-Moreno Universidad Autonoma de Nuevo Leon Av.Universidad s/nFacultad de Ingenierıa CivilSan Nicolas de los Garza N.L.C.P.66451Mexico Instituto Politecnico Nacional UPALMCol.LindavistaC.P.07338 Mexico D.F.Mexico

Mg–Xwt.%Ni(X=5 and 20)alloys have been prepared by mechanical alloying using milling times of 15 and 30 h in a planetary ball milling to know the effects of magnesium with the addition of Ni as catalyst,dispersion on the microstructure,area surface and the efficiency of hydrogen ***-EDS,XRD and Imagej^(■)software have been used to characterize the microstructure and chemical composition of the *** experiments were performed as batch-type tests at 200,250 and 300℃ under 2 MPa H2 pressure during 30 *** experiments resulted in varying amounts of MgH2 in the hydrided powders depending on composition and hydriding *** best results point to an optimum Ni dispersion,which in turn depends on Ni content and milling time.

关键词： Hydrogen storage Magnesium Niquel Alloy Characterization

Emotions,Perceptions and Health Behaviors of Adult Congenital Heart Disease Patients during COVID-19 in New York City

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Congenital Heart Disease 2022年第5期17卷 519-531页

作者： jodi L.Feinberg Peter Sheng Stephanie pena Adam j.Small Susanna Wendelboe Katlyn Nemani Vikram Agrawal Dan G.Halpern Leon H.Charney Division of Cardiology NYU Grossman School of MedicineNew YorkUSA Department of Medicine NYU Grossman School of MedicineNew YorkUSA Department of Psychiatry NYU Grossman School of MedicineNew YorkUSA Department of Cardiology Mount Sinai MorningsideNew YorkUSA

Background:Adults with congenital heart disease(ACHD)have increased prevalence of mood and anxiety *** are limited data regarding the influence of the COVID-19 pandemic on the mental health and health behaviors of these ***:The purpose is to evaluate the perceptions,emotions,and health behaviors of ACHD patients during the COVID-19 ***:In this cross-sectional study of ACHD patients,we administered surveys evaluating self-reported emotions,perceptions and health *** regressions were performed to determine the adjusted odds of displaying each perception,emotion and health behavior based on predictor ***:Ninety-seven patients(mean age 38.3 years,46.4%female,85.6%moderate or complex lesion)completed the *** majority of patients reported feeling moderately or very sad(63.1%),and 48.4%of patients identified themselves as feeling moderately or very *** majority of patients perceived their risk of COVID-19 as moderate or *** were more likely to report feeling sad and anxious(95%CI 1.06–10.96,p-value 0.039,and 95%CI 1.44–15.30,p-value=0.012,respectively),and were associated with higher odds of having a perceived increased risk of COVID-19(95%CI 1.33–10.59,p-value 0.012).There was no association between ACHD anatomic or physiologic classification and perceptions,emotions and health ***:Females were more likely to report feeling sad,anxious and an increased risk of COVID-19 in comparison to *** findings indicate the need for mental health support and promotion of health behaviors during the pandemic amongst all ACHD patients,regardless of underlying condition.

关键词： Adult congenital heart disease COVID-19 health behaviors anxiety depression

Effect of cerium/lanthanum addition on microstructure and mechanical properties of Al7075 alloy via mechanical alloying and sintering

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journal of Rare Earths 2016年第4期34卷 420-427页

作者： R.Pérez-Bustamante A.Reyna-Cruz D.C.Acosta-pena C.R.Santillán-Rodríguez j.A.Matutes-Aquino F.Pérez-Bustamante M.C.Maldonado-Orozco j.Aguilar-Santillán R.Martínez-Sánchez Research Center in Advanced Materials(CIMA V) National Laboratory of NanotechnologyMiguel de Cervantes No.120C.P.31109ChihuahuaChih.Mexico Faculty of Engineering Autonomous University of Chihuahua(UACH)Circuito No.1 Nuevo Campus UniversitarioC.P.31 125ChihuahuaChih.Mexico Faculty of Chemical Sciences Autonomous University of Chihuahua(UACH)Circuito No.1 Nuevo Campus UniversitarioC.P.31125ChihuahuaChih.Mexico Materials&Tools LLC 4118 E Washington CtGilbertAZUSA 85234

The effect of the Al-6Ce-3La（ACL） on the microstructural behavior of the Al7075 was investigated. Materials were synthesized by mechanical alloying with variation in the ACL content and milling time. Products were characterized and studied in the as-milled condition and mechanically evaluated after sintering. The synergetic effect of milling time and ACL content in the modified materials led to a reduction in the particle size. Results from electron microscopy showed a homogeneous dispersion of Ce/La phases up to 20 wt.% of ACL content after 10 h of milling. Mechanical evaluation under compressive test showed an improved performance for those alloys reinforced with 0.2 wt.% and 0.5 wt.% of ACL.

关键词： mechanical alloying rare earths aluminum microstructure sintering