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PtRu nanoparticles supported on noble carbons for ethanol electrooxidation

Journal of Energy Chemistry 2022年第3期31卷 168-180,I0006页

作者： Alberto Rodríguez-Gómez Enrico lepre luz Sánchez-Silva Nieves lópez-Salas Ana Raquel de la Osa Faculty of Chemical Sciences and Technologies University of Castilla-La ManchaEnrique Costa Novella Building.Avda.Camilo Jose Cela1213071 Ciudad RealSpain Colloid Chemistry Department Max Planck Institute of Colloids and InterfacesAm Mühlenberg 114476 PotsdamGermany

In this work,three cytosine derived nitrogen doped carbonaceous materials(noble carbons,NCs)with different atomic C/N ratios and porous networks have been synthesized and used as supports for Pt Ru electrocatalysts in the ethanol oxidation reaction(EOR)for clean hydrogen production.Both,the metal phase and the carbon support play critical roles in the electrocatalysts final performance.lower NPs size distribution was obtained over supports with low atomic C/N ratios(i.e.,4 and 6)and defined porosity(i.e.,1701 m^(2)g^(-1)for Pt Ru/CNZ and 1834 m^(2)g^(-1)for Pt Ru/ClZ,respectively).In contrast,a lower C/N ratio and poor porous network(i.e.,65 m^(2)g^(-1),Pt Ru/ClK)led to the largest particle size and fostered an increase of the alloying degree between Pt and Ru NPs(i.e.,3%for C/N~6 and 28%for C/N~3).Electrochemical active surface area was found to increase with decreasing NPs size and the alloy extent,due to a higher availability of Pt active sites.Accelerated degradation tests showed that Pt Ru/NCs outperform similar to Pt Ru NPs on commercial carbon pointing at the stabilizing effect of NCs.Pt Ru/CNZ exhibited the best electrochemical performance(i.e.,69.1 m A mgPt-1),outperforming Pt Ru/ClZ and Pt Ru/ClK by3-and 9-fold,respectively,due to a suitable compromise between particle sizes,degree of alloy,textural properties and elemental composition.Best anodes were scaled-up to a proton exchange membrane cell and Pt Ru/CNZ was proved to provide the best electrocatalytic activity(262 m A cm^(-2)and low energy requirements),matching the values obtained by the state of the art of EOR electrocatalysts.

关键词： Noble carbon Cytosine H2 production Ethanol electrooxidation PtRu anode PEM cell

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Qigong improves balance in young women: a pilot study

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Journal of Integrative Medicine 2013年第4期11卷 241-245页

作者： María Victoria González lópez-Arza enrique Varela-Donoso Jesús Montanero-Fernández Juan Rodríguez-Mansilla Blanca González-Sánchez luis González lópez-Arza Medicine and Surgery Department Extremadura University School of Medicine Adolor Research Group of the Extremadura University Physical and Rehabilitation Medicine Department Complutense University School of Medicine Mathematics Department Extremadura University School of Sciences Health Care Centre of Zafra

BACKGROUND： Balance problems are common in people of all ages and can lead to falls, thus causing fractures with consequent disability. Qigong practice has long been part of daily life in Chinese culture, and has good effects on physical health maintenance. OBJECTIVE： The present work describes the change in balance in young, healthy women after practising Qigong for eight weeks. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS： The study took the form of a controlled, randomised longitudinal trial, and involved 30 women aged 18-25 years. The subjects had no prior experience of Qigong or Tai Chi and were unaware of the aims of the study. Subjects were randomly assigned to a Qigong intervention group or a control group. Those in the Qigong intervention group performed ＂exercises in 20 figures for health and long-life＂（Wang Ziping） for 1 h twice per week, for 4 weeks. The control group undertook no exercise at all. MAIN OUTCOME MEASURES： The main outcome measure was the stabilometry values. These were obtained in a unipodal support test, using a plantar pressure platform with optical sensors. RESUlTS： The Qigong subjects showed a significant improvement in their stabilometry results （40.1% pre-intervention and 56.4% post-intervention）（P〈0.045）, while no improvement was seen in the control group （51.2% pre-intervention and 53.5% post-intervention）. At the beginning of the intervention, the stabilometry values recorded for the Qigong intervention group were worse than those recorded for the control group （40.15% and 51.21% respectively; P=0.121）. However, a comparison of the post-intervention values between these groups showed that these differences have disappeared （P=0.653）. CONClUSION： Qigong can improve balance in healthy, young women.

关键词： Qigong musculoskeletal equilibrium women pilot projects

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国际盆景协会佳作选登(五)

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花木盆景（下半月） 2024年第6期 64-67页

作者： [菲律宾]Charlie lee [波兰]Piotr Tomasz Czernichowski [韩国]Park Jae Heon [墨西哥]enrique Castano [印度尼西亚]Oka Sunarya [捷克]Vaclav Novak 罗民轩不详中国台湾

国际盆景协会(Bonsai Clubs International,BCI)于1963年在美国成立,会员分布在50多个国家和地区,每年在不同的国家或地区举行大会和年展,对世界盆景文化的发展起到了重要的推动作用。2023年9月,陈昌先生成功当选BCI主席,成为BCI历史上... 详细信息

国际盆景协会(Bonsai Clubs International,BCI)于1963年在美国成立,会员分布在50多个国家和地区,每年在不同的国家或地区举行大会和年展,对世界盆景文化的发展起到了重要的推动作用。2023年9月,陈昌先生成功当选BCI主席,成为BCI历史上首位中国籍主席。本栏目由花木盆景杂志社与BCI合办,让您通过BCI之窗,领略世界各地盆景魅力。

关键词：花木盆景盆景协会中国籍 BCI

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Demonstration of uncertainty resulting from MODerate resolution Imaging Spectroradiometer-like geometries:an albedo case study

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International Journal of Digital Earth 2016年第5期9卷 520-544页

作者： enrique l.Montaño Department of Geographical Sciences University of MarylandCollege ParkMDUSA

This research examines uncertainty in MODerate resolution Imaging Spectroradiometer(MODIS)observations,and demonstrates the direct influence of geometric distortions resulting from the standard practice of geolocating swath observations.MODIS observations vary dependent on the ground sample distance,which varies dependent on the view zenith angle that changes with every orbit.MODIS level 2G(l2G)land products are generated by applying a geolocation algorithm that resamples the variable observation geometries to a consistent grid of fixed pixel size and location,a process which itself introduces variability associated with the changing observational footprint.For this study,broadband albedo was simulated for five validation sites,representing five distinct land cover types,exhibiting quantifiable variability,with additional seasonal variability exhibited in some sites.All site simulations exhibit compounded uncertainty attributable to the geometric distortion sufficient to influence climate models(i.***.ranges from 0.01 to 0.045 albedo).These results indicate there is a minimum level of uncertainty associated with the variable geometry that should be factored into l2Gbased products,particularly for nominal 250 m band data.Aggregating the data to coarser resolutions and smoothing the data through average resampling can mitigate the uncertainty.

关键词： Earth observation geography land cover remote sensing visible/infrared remote sensing

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Frozen ground and periglacial processes relationship in temperate high mountains: a case study at Monte Perdido-Tucarroya area(The Pyrenees, Spain)

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Journal of Mountain Science 2020年第5期17卷 1013-1031页

作者： SERRANO enrique lópez-MORENO Juan Ignacio GóMEZ-lENDE Manuel PISABARRO Alfonso MARTíN-MORENO Raúl RICO Ibai AlONSO-GONZálEZ Esteban Dept of GeographyUniversity of ValladolidValladolid 47011Spain Dept of Geoenvironmental Processes and Global ChangePyrenean Institute of EcologyZaragoza 50.080Spain Dept.Specific Didactics.Autonom University of Madrid.Madrid 28049Spain Dept of GeographyPrehistory and ArcheologyUniversity of the Basque CountryVitoria 01006Spain

Seasonally frozen ground,mountain permafrost and cryogenic geomorphological processes are important components of the Pyrenean high mountains.This work presents the results of a study on the distribution of frozen ground in a marginal and paraglacial environment of temperate mountains.An inventory was made of landforms and indicators of frozen ground,and frozen ground was mapped accordingly.During 2014 and 2016 ground temperatures and thermal regimes were monitored,basal temperatures of snow-cover(BTS)were measured and a thermal map was drawn.Differential thermal behaviours were detected among different elevations and slope orientations.Periglacial processes are the most widespread,in which frost weathering and nivation,together with gelifluction and cryoturbation,are the most efficient processes;the latter two are generally linked to the presence of frozen ground.The fall in air and ground temperatures with altitude,slope orientations,and snowpack thickness and evolution determine ground thermal regimes.In the study area,three types of thermal regimes were established:climate-controlled,snowcover-controlled,and frozen ground-controlled.Seasonally frozen ground occurs across a broad range of elevation between 2650 and 3075 m asl,whereas possible permafrost only occurs above 2750 m asl.

关键词： Geomorphology Periglacial Seasonally frozen ground Mountain permafrost Pyrenees

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Contributions to data transmission at critical moments on unmanned aerial vehicles

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Chinese Journal of Aeronautics 2023年第8期36卷 247-257页

作者： Jose enrique RODRIGUEZ David SEGURADO Manuel SANCHEZ Jose Javier MARTINEZ Rafael GONZAlEZ National Institute of Aerospace Technology Madrid 28850Spain Department of Computer Science University of AlcalaAlcala de HenaresMadrid 28054Spain

As for unmanned aircraft, the knowledge of the aircraft performance is directly related with the navigation, guidance, and control system programming. Therefore, the measured data in each phase of the flight must be sufficiently precise to obtain a good characterization of aircraft.This article proposes new methods of sending information to ground, which make it possible to know the aircraft behavior accurately, and for this purpose, four contributions have been made for AlO(Avión ligero de Observación, Spanish acronym for light Observation Aircraft). Currently, the characterization is based on data obtained at ten samples per second, insufficient to acquire detailed knowledge of what happened during the whole flight of an aircraft. As a result of these contributions, many more samples per second of accelerations and angular velocities are obtained at the most critical moments of the flight, such as takeoff or landing. Among the improvements included are data compression techniques, providing references to locate the measured data in time and identifying labels of each parameter.

关键词： Critical moments Data transmission Datacompression tech-niques Radio-modem Recommended Standard 232(RS-232) Unmannedaerial vehicle

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Viability,behavior,and color expression in the offspring of matings between common wall lizard Podarcis muralis color morphs

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Current Zoology 2022年第1期68卷 41-55页

作者： Javier ABAlOS Guillem PEREZ I DE lANUZA Alicia BARTOlOME Fabien AUBRET Tobias UllER enrique FONT Ethology lab Instituto Cavanilles de Biodiversidad y Biologı´a EvolutivaUniversitat de ValenciaValenciaSpain CIBIO/InBIO Centro de Investigacao em Biodiversidade e Recursos Geneticos da Universidade do PortoPortoPortugal SETE Station d’Ecologie Theorique et ExperimentaleUPR2001Centre National de la Recherche ScientifiqueParisFrance Department of Biology Lund UniversityLundSweden

Color polymorphisms are widely studied to identify the mechanisms responsible for the origin and maintenance of phenotypic variability in nature.Two of the mechanisms of balancing selection currently thought to explain the long-term persistence of polymorphisms are the evolution of alternative phenotypic optima through correlational selection on suites of traits including color and heterosis.Both of these mechanisms can generate differences in offspring viability and fitness arising from different morph combinations.Here,we examined the effect of parental morph combination on fertilization success,embryonic viability,newborn quality,antipredator,and foraging behavior,as well as inter-annual survival by conducting controlled matings in a polymorphic lacertid Podarcis muralis,where color morphs are frequently assumed to reflect alternative phenotypic optima(e.g.,alternative reproductive strategies).Juveniles were kept in outdoor tubs for a year in order to study inter-annual growth,survival,and morph inheritance.In agreement with a previous genome-wide association analysis,morph frequencies in the year-old juveniles matched the frequencies expected if orange and yellow expressions depended on recessive homozygosity at 2 separate loci.Our findings also agree with previous literature reporting higher reproductive output of heavy females and the higher overall viability of heavy newborn lizards,but we found no evidence for the existence of alternative breeding investment strategies in female morphs,or morphcombination effects on offspring viability and behavior.We conclude that inter-morph breeding remains entirely viable and genetic incompatibilities are of little significance for the maintenance of discrete color morphs in P.muralis from the Pyrenees.

关键词： alternative breeding strategies color polymorphism controlled matings lizard behavior morph ontogeny newborn viability

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Antifungal Activity of Crude Extracts of Tectona grandis l.f. against Wood DecayFungi

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Phyton-International Journal of Experimental Botany 2022年第8期91卷 1795-1808页

作者： enrique Cárcamo-Ibarra Mauro Manuel Martínez-Pacheco Abril Munro-Rojas Jorge enrique Ambriz-Parra Crisanto Velázquez-Becerra Facultad de Ingeniería en Tecnología de la Madera Universidad Michoacana de San Nicolás de HidalgoMorelia58030México Instituto de Investigaciones Químico-Biológicas Universidad Michoacana de San Nicolás de HidalgoMorelia58030México

Wood is mainly made up of cellulose, hemicelluloses, lignin polymers and other organic and inorganic substances, making it susceptible to deteriorate by various biological agents. Tectona grandis l.f. (Teak) is a timberspecies with high resistance to biological deterioration, valued for its durability, beauty, and mechanical resistance.The purpose of this work was to evaluate the antifungal activity of crude extracts from teak on various fungi thatcause wood deterioration. For this, Teak heartwood was obtained, then fragmented and pulverized until obtaininga flour which was used for compounds extraction using the Soxhlet technique coupled to a rotary evaporatorthrough solvents of increasing polarity (hexane, dichloromethane, tetrahydrofuran, and acetone). The extractsobtained were tested against fungal organisms collected in the field, and the lC50 was determined using teak crudeextracts on Artemia salina as a biological model. The results obtained showed that a high flour yield was obtainedwith hexane (0.951 g), followed by tetrahydrofuran (0.446 g), dichloromethane (0.348 g), and acetone (0.152 g). Byusing nine fungal organisms that predominantly correspond to the genus Aspergillus, the extractable compoundswere tested, inhibiting 25% of mycelial growth with tetrahydrofuran (T. versicolor), and 40.9% with dichloromethane(G. trabeum). likewise, the biological model of A. salina showed an lC50 of 84.9 μg/ml with hexane, 43.3 μg/mlwith dichloromethane, 59.6 μg/ml with tetrahydrofuran, and 54.7 μg/ml with acetone. For this reason, it is concluded that Teak wood contains many extractable compounds in relation to its weight, besides having antimicrobialactivity when extracted through polar compounds such as dichloromethane and tetrahydrofuran.

关键词： Tectona grandis wood deterioration naphthoquinone antifungal activity wood protection

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Unsupervised full-color cellular image reconstruction through disordered optical fiber

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light(Science & Applications) 2023年第6期12卷 1091-1102页

作者： Xiaowen Hu Jian Zhao Jose enrique Antonio-lopez Rodrigo Amezcua Correa Axel Schülzgen CREOl The College of Optics and PhotonicsUniversity of Central FloridaOrlandoFL 32816USA The Picower Institute for learning and Memory Massachusetts Institute of TechnologyCambridgeMA 02139USA

Recent years have witnessed the tremendous development of fusing fiber-optic imaging with supervised deep learning to enable high-quality imaging of hard-to-reach areas.Nevertheless,the supervised deep learning method imposes strict constraints on fiber-optic imaging systems,where the input objects and the fiber outputs have to be collected in pairs.To unleash the full potential of fiber-optic imaging,unsupervised image reconstruction is in demand.Unfortunately,neither optical fiber bundles nor multimode fibers can achieve a point-to-point transmission of the object with a high sampling density,as is a prerequisite for unsupervised image reconstruction.The recently proposed disordered fibers offer a new solution based on the transverse Anderson localization.Here,we demonstrate unsupervised full-color imaging with a cellular resolution through a meter-long disordered fiber in both transmission and reflection modes.The unsupervised image reconstruction consists of two stages.In the first stage,we perform a pixel-wise standardization on the fiber outputs using the statistics of the objects.In the second stage,we recover the fine details of the reconstructions through a generative adversarial network.Unsupervised image reconstruction does not need paired images,enabling a much more flexible calibration under various conditions.Our new solution achieves full-color high-fidelity cell imaging within a working distance of at least 4 mm by only collecting the fiber outputs after an initial calibration.High imaging robustness is also demonstrated when the disordered fiber is bent with a central angle of 60°.Moreover,the cross-domain generality on unseen objects is shown to be enhanced with a diversified object set.

关键词： fiber optical image

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Structural Analysis of TiC and TiC-C Core-Shell Nanostructures Produced by Pulsed-laser Ablation

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Journal of Materials Science and Chemical Engineering 2023年第7期11卷 1-13页

作者： luis enrique Iniesta Piña Miguel Ángel Camacho lópez Rafael Vilchis Néstor Víctor Hugo Castrejón Sánchez Delfino Reyes Contreras Mestría en Ciencia de Materiales Facultad de Química Campus Rosedal Universidad Autónoma del Estado de México Toluca México laboratorio de Fotomedicina Biofotónica y Espectroscopía Láser de Pulsos Ultracortos Facultad de Medicina Universidad Autónoma del Estado de México Toluca México Centro Conjunto de Investigación en Química Sustentable UAEM-UNAM Toluca México TecNM/Tecnológico de Estudios Superiores de Jocotitlán Jocotitlán México laboratorio de Acústica y Nanomateriales Facultad de Ciencias Campus el Cerrillo Universidad Autónoma del Estado de México Toluca México

This paper reports on the ablation process of a pure Ti solid target immersed in a C-enriched acetone solution, leading to the production of titanium carbide (TiC) and Ti-C core-shell nanostructures. The used route of synthesis is generally called pulsed laser ablation in liquid (PlAl). The presence of carbon structures in the solution contributed to the carbon content in the produced Ti-based nanomaterials. The atomic composition of the produced nanostructures was analyzed using SEM-EDS, while TEM micrographs revealed the formation of spherical TiC and core-shell nanostructures ranging from 40 to 100 nm. The identification of atomic planes by HRTEM confirmed a 10 nm diameter C-shell with a graphite structure surrounding the Ti-core. Raman spectroscopy allowed for the identification of D and G peaks for graphite and a Raman signal at 380 and 600 cm−1, assigned to TiC. The results contribute to the state-of-the-art production of TiC and Ti-C core-shell nanostructures using the PlAl route.

关键词： laser Ablation TiC Nanoparticles Core-Shell Nanoparticles Pulsed laser

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