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Perpendicularly Self-Oriented and Shape-Controlled L10-FePt Nanorods Directly Synthesized by a Temperature-Modulated Process

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Nano Research 2011年第7期4卷 666-674页

作者： tiago Luis da silva Laudemir Carlos Varanda Colloidal Materials Group Instituto de Quimica de Sao Carlos Universidade de Sao Paulo--USP Sao Carlos PO Box 780 13566-590 Brazil

The synthesis and self-assembly of tetragonal phase-containing L10-Fe55Pt45 nanorods with high coercive field is described. The experimental procedure resulted in a tetragonal/cubic phase ratio close to 1：1 for the as-synthesized nanoparticles. Using different surfactant/solvent proportions in the process allowed control of particle morphology from nanospheres to nanowires. Monodisperse nanorods with lengths of 60 ＋ 5 nm and diameters of 2-3 nm were self-assembled in a perpendicular oriented array onto a substrate surface using hexadecylamine as organic spacer. Magnetic alignment and properties assigned, respectively, to the shape anisotropy and the tetragonal phase suggest that the self-assembled materials are a strong candidate to solve the problem of random magnetic alignment observed in FePt nanospheres leading to applications in ultrahigh magnetic recording （UHMR） systems capable of achieving a performance of the order of terabits/in2.

关键词： Magnetic materials data storage FePt nanorods self-assembl~ perpendicular magnetic alignment

How far have we come?Review of main public policies to reduce landslide impacts in Brazil

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Journal of Mountain Science 2024年第9期21卷 2891-2904页

作者： Bianca Carvalho VIEIRA tiago damas MARTINS Telma Mendes da silva JoséEduardo BONINI Department of Geography University of São PauloAvenida Professor Lineu Prestes 05508-000Brazil Cities Institute Federal University of São PauloAvenida Jacu-Pêssego 08260-001Brazil Department of Geography Federal University of Rio de JaneiroAvenida Athos da Silveira Ramos 21941-916Brazil

During the rainy season in Brazil,landslides can have catastrophic consequences,including loss of life,damage to urban infrastructure and significant economic ***,more than eight million people in Brazil live in disaster-prone *** objective of this article is to present a chronological review of the principal policies and programmes at the national,state,and municipal levels,with an emphasis on their key actions aimed at mitigating the impact of disasters related to natural hazards,particularly *** analysis was based on official records of public policies from the national,state,and municipal *** results show that several initiatives were initially developed at the local and regional ***,it was not until the late 1980s that a comprehensive organisation of civil protection at the national level emerged as a response *** is possible to highlight three phases(understanding,coexistence,and prevention)of institutional action focused on risk management in the face of *** the growing knowledge of risk scenarios,disasters continue to occur in Brazil on an annual basis,revealing several obstacles to reducing their impact,particularly given the social and economic disparities between Brazilian regions and the applicability of public policies that must overcome the limitations of each municipality.

关键词： Disasters Risk Mitigation Prevention Legislation Civil Defense Natural Hazards

The interplay between leaf water potential and osmotic adjustment on photosynthetic and growth parameters of tropical dry forest trees

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Journal of Forestry Research 2023年第1期34卷 177-186页

作者： tiago de Sousa Leite Romulo Magno Oliveira de Freitas Nildo da silva Dias Jeferson Luiz dallabona Dombroski Narjara Walessa Nogueira Federal University of Mato Grosso CuiabáMTBrazil Federal Institute of Education Science and Technology of Rio Grande do NortePau dos FerrosRNBrazil Federal Rural University of the Semi-Arid Region MossoróRNBrazil

Mimosa tenuiflora and Piptadenia stipulacea are commonly accepted as drought-tolerant species but little is known about their response to drought followed by ***,the interplay between leaf water potential and osmotic adjustment on photo synthetic and growth parameters of these species was examined.A greenhouse study was conducted in a split-plot design with two water conditions in the main plots(control;drought followed by rehydration),and eight sampling times in the subplots(1,4and 7 days of drought,and 1,3,6,12,and 17 days of rehydration).Plant water status and biochemical changes were assessed as well as leaf gas exchange and subsequent *** drought stress,both species maintained a low leaf water potential throughout the day by accumulating compatible solutes,thus allowing a rapid and full recovery of water status when *** these plants minimized water loss by closing their stomata,neither showed stomatal limitations to *** inhibition of this process during drought was possibly related to mesophyll limitations as well as to a reversible downregulation of photo systems,along with adjustments of their *** deficits also triggered morphological adaptations at the whole plant level,leading to reduced growth,mainly of the shoots in *** and the roots in ***.

关键词： Drought stress Rehydration Gas exchange Plant biomass

Atmospheric River Signatures in Radiosonde Profiles and Reanalyses at the Dronning Maud Land Coast,East Antarctica

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Advances in Atmospheric Sciences 2020年第5期37卷 455-476页

作者： Irina V.GORODETSKAYA tiago silva Holger SCHMITHUSEN Naohiko HIRASAWA Centre for Environmental and Marine Studies(CESAM) Department of PhysicsUniversity of AveiroAveiro 3810-193Portugal Department of Atmospheric and Cryospheric Sciences University of InnsbruckInnsbruck 6020Austria Alfred Wegener Institute Helmholtz Centre for Polar and Marine ResearchBremerhaven 27570Germany National Institute of Polar Research Tachikawa 190-8518Japan SOKENdaI(Graduate University for Advanced Studies) Hayama 240-0193Japan

Atmospheric rivers(ARs)are an important component of the hydrological cycle linking moisture sources in lower latitudes to the Antarctic surface mass *** investigate AR signatures in the atmospheric vertical profiles at the Dronning Maud Land coast,East Antarctica,using regular and extra radiosonde measurements conducted during the Year of Polar Prediction Special Observing Period November 2018 to February *** AR events affecting the locations of Neumayer and Syowa cause a strong increase in specific humidity extending through the mid-troposphere and a strong low-level jet(LLJ).At Neumayer,the peak in the moisture inversion(up to 4 g kg^?1)is observed between 800 and 900 hPa,while the LLJ(up to 32 m s^?1)is concentrated below 900 *** Syowa the increase in humidity is less pronounced and peaks near the surface,while there is a substantial increase in wind speed(up to 40 m s?1)between 825 and 925 *** transport(MT)within the vertical profile during the ARs attains a maximum of 100 g kg?1 m s?1 at both locations,and is captured by both ERA-Interim and ERA5 reanalysis data at Neumayer,but is strongly underestimated at *** of the enhanced MT events during 2009?19 show that these events represent an extreme state of the lower-tropospheric profile compared to its median values with respect to temperature,humidity,wind speed and,consequently,*** temporal-and vertical-resolution radiosonde observations are important for understanding the contribution of these rare events to the total MT towards Antarctica and improving their representation in models.

关键词： Antarctica moisture transport radiosonde observations YOPP-SOP-SH reanalysis

Association of sleep quality with sociodemographic factors and lifestyle in adolescents from southern Brazil

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World Journal of Pediatrics 2018年第4期14卷 383-391页

作者： tiago Rodrigues de Lima Diego Augusto Santos silva Physical Education Department Federal University of Santa CatarinaProfessor Clementino de Britto Street362 ap 334 CapoeirasFlorianópolisSanta CatarinaBrazil

Background Good sleep quality is an essential component for growth, development, and physical and mental health of the individual, in addition to being a positive indicator of health and well-being. The objective of this study was to estimate the prevalence of poor sleep quality and to identify the association of poor sleep quality with sociodemographic factors, lifestyle, weight status, and associated aerobic fitness in adolescents. Methods This study included 1110 students aged 14–19 years from city of S?o José/SC, Brazil. Sleep quality of the subjects was assessed using a questionnaire and classified as adequate and low. Independent variables were gender, age, monthly household income, maternal education, school shift, global physical activity, proper diet, screen time, sleeping hours of full week, sleeping hours of weekdays, sleeping hours of weekends, weight status, and aerobic fitness. Binary logistic regression was used to estimate odds ratios and confidence intervals of 95%. Results Prevalence of poor sleep quality was 60.4%. More likely to have poor sleep quality were identified in female students (OR 1.68, 95% CI 1.11–2.55), whose mothers had higher levels of education (OR 1.44, 95% CI 1.20–1.73) and low aerobic fitness (OR 1.80, 95% CI 1.02–3.19). Conclusion Adolescents who were most likely to report poor sleep quality were female, those whose mothers had a higher educational level and had low aerobic fitness. Students with sedentary risk behavior were less likely of reporting poor sleep quality.

关键词： Adolescents Brazil Cross-sectional studies Demographic indicators Sleep hygiene

Elastically restrained Bernoulli-Euler beams applied to rotary machinery modelling

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Acta Mechanica Sinica 2011年第1期27卷 56-62页

作者： tiago A.N.silva Nuno M.M.Maia ISEL Polytechnic Institute of LisbonDepartment of Mechanical EngineeringRua Conselheiro Emídio Navarro IDMEC-IST Technical University of LisbonDepartment of Mechanical Engineering

Facing the lateral vibration problem of a machine rotor as a beam on elastic supports in bending,the authors deal with the free vibration of elastically restrained Bernoulli-Euler beams carrying a finite number of concentrated elements along their *** on Rayleigh’s quotient,an iterative strategy is developed to find the approximated torsional stiffness coefficients,which allows the reconciliation between the theoretical model results and the experimental ones,obtained through impact *** mentioned algorithm treats the vibration of continuous beams under a determined set of boundary and continuity conditions, including different torsional stiffness coefficients and the effect of attached concentrated masses and rotational inertias, not only in the energetic terms of the Rayleigh’s quotient but also on the mode shapes,considering the shape functions defined in *** loading cases are examined and examples are given to illustrate the validity of the model and accuracy of the obtained natural frequencies.

关键词： Transverse vibration of beams · Elastic supports · Torsional stiffness coefficients

Electromagnetic Characterization of Recyclable Polymer Nanofibers Based on PSU/Carbonyl Iron

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Journal of Renewable Materials 2019年第3期7卷 279-287页

作者： daniel Consoli Silveira tiago Teixeira da silva Braga daniel Molina Gil Newton Adriano dos Santos Gomes Lilia Müller Guerrini Edson Cocchieri Botelho Department of Materials and Technology Sao Paulo State University(UNESP)School of EngineeringGuaratinguetá/SP-Brazil Electronic Warfare Laboratory Technological Institute of Aeronautics(ITA)Sao Josédos Campos/SP-Brazil Institute of Science and Technology Federal University of Sao Paulo(UNIFESP)Sao Josédos Campos/SP-Brazil

This study investigated and defined the optimal processing parameters for the electrospinning of polysulfone polymer solutions with N,*** of parameters such as solute concentration,electrical voltage,and working distance were correlated with the quality of the obtained nanofibers using morphological characterization via scanning electron microscopy(SEM).Carbonyl iron additive was dispersed in the polymer solutions,using ultrasonic tip,and the material processed via electrospinning with aforementioned parameters *** with the property of interaction with electromagnetic waves were *** dispersion of different concentrations of the additive and electromagnetic characterizations in the X-band of microwaves(8.2 and 12.4 GHz),using vector network analyzer(VNA)and rectangular waveguide,allowed the identification of the materials electromagnetic *** parameters allowed the calculation of reflected and transmitted energy by the material.

关键词： Carbonyl iron electromagnetic characterization electrospinning nanofibers polysulfone

SF^2HDL： A Computational Tool of State Transition Diagram Translation

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Journal of Mechanics Engineering and Automation 2013年第2期3卷 78-86页

作者： tiago da silva Almeida Alexandre César Rodrigues da silva Dept. of Electrical Engineering UNESP - Univ. Estadual Paulista llha Solteira 15385-000 Brazil

The lack of standard to electronic circuits modeling made possible the development of many tools and modeling languages for electronic circuits. In this way, several tools to be used on different descriptions stage of the designs are necessary. This paper presents a tool called SF^2HDL （Stateflow to Hardware Description Language or State Transition Table） that translates a finite state machine on state transition diagram representation, described by Stateflow tool, into an input file standard for TABELA program or into a file behavioral VHDL （Very High Speed Integrated Circuits Hardware Description Language） directly. The TABELA program was used to optimization this finite state machine. After that, the TAB2VHDL program was used to generate the VHDL code on register transfer level, what permits comparisons with results obtained by synthesis. The finite state machine must be described by Mealy model and the user can describe the machine on high level abstraction using all Simulink supports. The tool was very efficient on computational cost and it made translation of several cases, for the two VHDL description models. Every state machine translated was simulated and implemented on device EP2C20F484C7 using Quartus II environment.

关键词： Finite state machine VHDL (very high speed integrated circuits hardware description language) synthesis HDB3 (highdensity bipolar 3) computational tool.

19-year remotely sensed data in the forecast of spectral models of the environment

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International Journal of Digital Earth 2021年第8期14卷 1040-1066页

作者： Fernando Saragosa Rossi Carlos Antonio da silva Junior JoséFrancisco de Oliveira-Júnior Paulo Eduardo Teodoro Luciano Shozo Shiratsuchi Mendelson Lima Larissa Pereira Ribeiro Teodoro Auana Vicente tiago Guilherme Fernando Capristo-silva State University of Mato Grosso(UNEMAT) Alta FlorestaMato GrossoBrazil Department of Geography State University of Mato Grosso(UNEMAT)SinopMato GrossoBrazil cFederal University of Alagoas(UFAL) MaceióAlagoasBrazil dFederal University of Mato Grosso do Sul(UFMS) Chapadão do SulMato Grosso do SulBrazil eAgCenter School of PlantEnvironmentaland Soil SciencesLouisiana State University(LSU)Baton RougeLouisianaUSA fPostgraduate Program in Agronomy Federal University of Mato Grosso(UFMT)SinopMato GrossoBrazil

The aims of this study were:i)to compare no-till areas in two municipalities located in different regions of Brazil,along with the influence on CO_(2)Flux and GPP,and ii)to verify the difference between environmental factors followed by the trends of these variables regarding future scenarios(ARIMA time-series model number).The study was carried out in two areas with different latitudes in the municipalities of Sinop-MT and Passo Fundo-RS,both in Brazil.A time series of 19 years was performed with data acquired by remote sensing from the following satellites:i)Landsat-8(OLI and TIRS),and ii)TERRA/AQUA(MODIS).The results propound that the spectro-temporal variables are directly influenced by soil management and agricultural practices over the observation time,with a satisfactory correlation in future predictions of the variables for the next ten years,in which presented that the variation of GPP and albedo values for the two study sites would gradually increase until 2028 and the temperature remained constant between the range of its seasonality,and CO_(2)Flux tends to decrease in its seasonality,indicating a higher CO_(2) absorption.

关键词： ARIMA numerical modeling remote sensing orbital products tillage