The Effect Of 4-halogenobenzoate Ligands On Luminescent And Structural Properties Of Lanthanide Complexes: Experimental And Theoretical Approaches

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The ligands 4-fluorobenzoate (4-fba), 4-chlorobenzoate (4-cba), 4-bromobenzoate (4-bba) and 4-iodobenzoate (4-iba) were chosen in order to synthesize europium(III), gadolinium(III) and terbium(III) complexes and compare the effect of halogens on their physical chemistry and luminescent properties. The homobimetallic complex [Eu(4-iba)(3)(H2O)(dmf)](2) crystallizes in the monoclinic P2(1)/c space group with unit cell parameters a = 8.3987(9) angstrom, b = 25.314(3) angstrom, c = 14.1255(17) angstrom, and beta = 105.347(2)degrees 1. FTIR spectroscopy indicates that the bidentate bridging mode of the carboxylato ligand was present in all complexes while bidentate chelate and a mixture of bidentate bridging and chelate modes were also found. According to emission spectra profiles and the Judd-Ofelt parameters the halogen of ligand molecules modifies the chemical environment symmetry around the europium(III) ion in their respective complexes. The complexes [Eu(4-fba)(3)(H2O)(2)] and [Eu(4-iba)(3)(H2O)(2)] have the highest symmetry around the europium(III) while the complexes [Eu(4-cba)(3)]center dot 2H(2)O, [Eu(4-bba)(3)]center dot 5/2H(2)O and [Eu(4-iba)(3)(H2O)(dmf)](2) have the lowest. The different halogens at the para position do not change the covalence degree of Eu-O bonds significantly, however they play a role in the ligand to metal charge transfer energies. The highest non-radiative energy transfer rates from ligand to europium(III) were found for the complexes [Eu(4-cba)(3)]center dot 2H(2)O and [Eu(4-bba)(3)]center dot 5/2H(2)O.39318831891Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)NSF [CHE 1363325]Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP [2008/53868-0]FAPESP [2009/54066-7

Be(com)ing an excelent student: a qualitative study with engineering undergraduates

This study explores the factors affecting the development of academic excellence on a group of 33 high-achieving engineering students. Participants were interviewed individually to explore several personal and contextual aspects of their past and current academic pathways. The results obtained reflect three main contributions to the conceptualization and understanding of excellence in academic contexts: the need to adopt a multidimensional and dynamic view about the concept of excellence; the existence of a variety of possible pathways and environmental conditions to achieve excellence; and the understanding of excellence as a process undergoing continuous development, which thrives within the family context and school environment, and that seems to be continuously nurtured by individuals in interaction with their contexts

Adaptação e validação do questionário de motivação para a prática deliberada em contexto académico: análise em alunos de engenharia com desempenho excelente

A diferenciação individual dos alunos tem sido cada vez mais importante e valorizada, tornando-se paralelamente importante a identificação e compreensão dos aspectos que distinguem os melhores alunos nos seus métodos de trabalho e nas suas características psicológicas. Um dos aspectos que tem merecido particular atenção na psicologia da educação diz respeito à motivação dos alunos face às suas tarefas, representando este um factor importante na compreensão do rendimento académico dos alunos. Nesta comunicação iremos apresentar os resultados preliminares da adaptação e validação do Questionário de Motivação para a Prática Deliberada em contexto académico, partindo da versão original desenvolvida por De Bruin, Rikers & Schmidt (2007). A análise factorial da escala adaptada para o contexto académico sugere a composição em dois factores: Mestria/ Aperfeiçoamento e Realização Pessoal. Foram igualmente obtidos níveis bastante aceitáveis de consistência interna nas duas subescalas e na escala total (.72, .70 e .76, respectivamente). Verificam-se, ainda, diferenças estatisticamente significativas a favor do grupo de alunos excelentes na subescala da Realização Pessoal, com o grupo de alunos excelentes a obter níveis mais elevados nesta dimensão motivacional

Matrix Converter-Based Unified Power-Flow Controllers: Advanced Direct Power Control Method

This paper presents a direct power control (DPC) for three-phase matrix converters operating as unified power flow controllers (UPFCs). Matrix converters (MCs) allow the direct ac/ac power conversion without dc energy storage links; therefore, the MC-based UPFC (MC-UPFC) has reduced volume and cost, reduced capacitor power losses, together with higher reliability. Theoretical principles of direct power control (DPC) based on sliding mode control techniques are established for an MC-UPFC dynamic model including the input filter. As a result, line active and reactive power, together with ac supply reactive power, can be directly controlled by selecting an appropriate matrix converter switching state guaranteeing good steady-state and dynamic responses. Experimental results of DPC controllers for MC-UPFC show decoupled active and reactive power control, zero steady-state tracking error, and fast response times. Compared to an MC-UPFC using active and reactive power linear controllers based on a modified Venturini high-frequency PWM modulator, the experimental results of the advanced DPC-MC guarantee faster responses without overshoot and no steady-state error, presenting no cross-coupling in dynamic and steady-state responses

Direct Power Control of Matrix Converter Based Unified Power Flow Controllers

This paper presents the Direct Power Control of Three-Phase Matrix Converters (DPC-MC) operating as Unified Power Flow Controllers (UPFC). Since matrix converters allow direct AC/AC power conversion without intermediate energy storage link, the resulting UPFC has reduced volume and cost, together with higher reliability. Theoretical principles of DPC-MC method are established based on an UPFC model, together with a new direct power control approach based on sliding mode control techniques. As a result, active and reactive power can be directly controlled by selection of an appropriate switching state of matrix converter. This new direct power control approach associated to matrix converters technology guarantees decoupled active and reactive power control, zero error tracking, fast response times and timely control actions. Simulation results show good performance of the proposed system

Joint Carrier-Phase Estimation for Digital Subcarrier Multiplexing Systems With Symbol-Rate Optimization

Digital subcarrier multiplexing (SCM) has recently emerged as a promising solution for next-generation ultra-high-baudrate coherent optical communication systems. Among its distinctive advantages over traditional single-carrier modulation, SCM enables the exploitation of symbol-rate optimization (SRO), which has been shown to enable the passive mitigation of the nonlinear interference noise (NLIN) that is generated during propagation over dispersion-unmanaged optical fiber systems. However, the full exploitation of SRO-based NLIN mitigation is severely hindered by the uncompensated distortion caused by laser phase noise (LPN) and non-linear phase noise (NLPN), whose impact is magnified by the use of low-baudrate subcarriers. Resorting to low-complexity carrier phase estimation (CPE) algorithms, in this paper we experimentally demonstrate that it is possible to overcome the hurdles posed by LPN and NLPN in SCM systems, provided that adequate joint-subcarrier CPE processing is employed. A dual-stage joint-processing approach composed of a pilot-based CPE optionally followed by a blind phase search (BPS)-based estimator is implemented and experimentally assessed, enabling to effectively optimize the symbol-rate per subcarrier down to 3 GBaud, in accordance with the theoretical SRO predictions for the system under test. In addition, we demonstrate that signal-to-noise ratio (SNR) gains of more than 1 dB can be achieved through joint-subcarrier CPE processing in shorter-reach links, while this gain tends to progressively reduce with increasing propagation distance, down to about 0.5 dB gain after 3000 km propagation

Non-Destructive Inspection of High Temperature Piping Combining Ultrasound and Eddy Current Testing

Project Hi2TRUST—Second generation platform for high-temperature component inspection, (Ref. 3335), supported by Fundo Europeu de Desenvolvimento Regional (FEDER), Programa Operacional Regional de Lisboa (Lisb@2020 and Portugal2020). Publisher Copyright: © 2023 by the authors.This paper presents an automated Non-Destructive Testing (NDT) system for the in-service inspection of orbital welds on tubular components operating at temperatures as high as 200 °C. The combination of two different NDT methods and respective inspection systems is here proposed to cover the detection of all potential defective weld conditions. The proposed NDT system combines ultrasounds and Eddy current techniques with dedicated approaches for dealing with high temperature conditions. Phased array ultrasound was employed, searching for volumetric defects within the weld bead volume while Eddy currents were used to look for surface and sub-surface cracks. The results from the phased array ultrasound results showed the effectiveness of the cooling mechanisms and that temperature effects on sound attenuation can be easily compensated for up to 200 °C. The Eddy current results showed almost no influence when temperatures were raised up to 300 °C.publishersversionpublishe

Endemic Angiostrongyliasis, Rio de Janeiro, Brazil

Submitted by Sandra Infurna ([email protected]) on 2016-10-06T12:58:28Z No. of bitstreams: 1 fernando_monteiro_etal_IOC_2011.pdf: 214467 bytes, checksum: 7938fea29a355143991cd4f518b2d970 (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2016-10-06T13:12:13Z (GMT) No. of bitstreams: 1 fernando_monteiro_etal_IOC_2011.pdf: 214467 bytes, checksum: 7938fea29a355143991cd4f518b2d970 (MD5)Made available in DSpace on 2016-10-06T13:12:13Z (GMT). No. of bitstreams: 1 fernando_monteiro_etal_IOC_2011.pdf: 214467 bytes, checksum: 7938fea29a355143991cd4f518b2d970 (MD5) Previous issue date: 2011Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil / Universidade Federal Rural do Rio de Janeiro. Seropédica, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil.Universidade Federal Rural do Rio de Janeiro. Seropédica, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil

Reliability of arterialized venous blood samples

The venous blood samples collected from the hand and from the ear lobule after heating have been used as a substitute of the arterial blood samples. Objective: The aim of this study was to determine the efficiency and reliability of this method during rest and exercise. Methods: The venous blood samples were collected (n = 14, 22 ± 3 yr., 71.3 ± 15.5 kg) on the back of the hand before and after immersion in warm water (41-43° C). ANOVA and Tukey post hoc test (P < 0.05) were used for statistical analysis. Results: The arterialized blood samples were signficantly lower on the [Lac] (-0.45 ± 0.49 mmoW 1); [HCO3] (-1.04 ± 2,76 mmoM'1) and PC02 (-5.51 ± 7.4 mmHg) in contrast an increment on the pH (0.040 ± 0.044), P02 (30.3 ± 26.2 mmHg) and %S02 (18.9 ± 18.1%) was perceived. No differences were found among the variables, except for P02, when measured in three differents moments. The lactate concentration in ear lobule capillary blood samples did not differ of the arterialized blood samples, and showed strong correlation (r = 0.95) during progressive exercise on cycle ergometer. Conclusion: The heating hand technique for arterialized blood samples was useful and reliable to study acid-base balance during rest and effort.Amostras de sangue venoso coletadas do dorso da mão após o aquecimento vêm sendo empregadas como substitutas para as coletas arteriais. Objetivo: Determinar a eficiência e confiabilidade desta manobra durante o repouso e no esforço. Métodos: Coletou-se amostras venosas do dorso da mão e do lóbulo da orelha de 14 sujeitos (22 ± 3 anos; e 71,3 ± 15,5 kg) antes e após a imersão por 15 minuto em água a 41-43 °C. Os dados foram tratados pela ANOVA com o teste post hoc de Tukey e análise de regressão para P medidas em três diferentes momentos. As concentrações do lactato no sangue capilar do lóbulo da orelha e do sangue venoso arterializado não diferiram e apresentaram forte correlação (r = 0,95) durante o esforço escalonado no ciclo ergômetro. Conclusão: O método do aquecimento da mão é útil e confiável para estudos do equilíbrio ácido-base, no repouso e no esforço

Desempenho do melão rendilhado em função da profundidade de gotejo e utilização de mulching

The modern techniques of water supply through irrigation can substantially reduce water waste, which contributes to attend the enlarging water demand. The objective of this work was to study the influence of subsurface drip irrigation and mulching over melon yield and quality characteristics, in a sandy soil (Typic Hapludox). The experimental design was blocks at random, with four replications. Treatments were displayed in a 2 x 3 factorial (with and without mulching x surface and 0.20 and 0.40 depth subsurface drip irrigation). Mulching using double-sided silver/black film increased fruit average mass, plant production, yield, daily growth rate for plant height and crown diameter, fruit distal diameter, and pulp thickness. The subsurface drip irrigation at 0.20 m depth resulted in larger fruit average mass, plant production, and yield than surface and 0.40 m depth drip irrigation.As atuais técnicas de aplicação de água pelos sistemas de irrigação podem reduzir substancialmente os desperdícios de água, o que contribui para atender a crescente demanda por esse recurso natural. O objetivo deste trabalho foi estudar aspectos produtivos e de qualidade de frutos de melão rendilhado em sistema de gotejo subterrâneo e cobertura plástica (mulching), em solo arenoso (Latossolo Vermelho-Amarelo). O delineamento adotado foi em blocos casualizados, com quatro blocos, com o arranjo dos tratamentos em fatorial 2 x 3 (com e sem mulching x gotejo superficial e subsuperficial, a 0,20 e 0,40 m de profundidade). O mulching utilizando filme dupla-face prateado/preto incrementou a massa média de fruto, a produção por planta, a produtividade, a taxa de crescimento diário da altura de planta e do diâmetro do colo da planta, o diâmetro longitudinal do fruto e a espessura de polpa. A profundidade de gotejo a 0,20 m resultou em maior massa média de fruto, produção por planta e produtividade quando comparado ao gotejo superficial ou em subsuperfície, a 0,40 m.(CNPq) National Council for Scientific and Technological Developmen