Luminescence Enhancement of Carboxyl-Coated CdTe Quantum Dots by Silver Nanoparticles

Metallic nanoparticles (NPs) have been used to improve the sensibility of biosensors and bioassays either by enhancing radiative emission or inducing quenching process on fluorescent probes. The aim of this research was to study the interaction of silver and silver-pectin NPs with water-dispersed carboxyl-coated cadmium telluride (CdTe) quantum dots (QDs). Metallic NPs were observed to change the emission of these fluorophores through local field effects. In a solution-base platform, an increase of 82 % was observed for the CdTe emission due to the interaction of QDs and silver-pectin NPs. QDs interaction with silver NPs without pectin was also investigated and a smaller emission enhancement of 20 % was detected. We observed that the NPs' nature and QDs' surface charge and concentration are important parameters for NPs-QDs interaction. Moreover, the presence of the pectin polymer shows to be a key component to the observed fluorescence enhancement. © 2013 Springer Science+Business Media New York.

Enhancement of voltammetric determination of quinizarine based on the adsorption at surfactant-adsorbed-layer in disposable electrodes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Enhancement of quality and stability of dried papaya by pectin-based coatings as air-drying pretreatment

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Prior Heavy-Intensity Exercise's Enhancement of Oxygen-Uptake Kinetics and Short-Term High-Intensity Exercise Performance Independent of Aerobic-Training Status

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Soft color enhancement of the production of J/psi's by neutrinos

We calculate the production of J/ψ mesons by neutrino-nucleon collisions in fixed target experiments. Soft color, often referred to as color evaporation effects, enhances production cross sections due to the contribution of color octet states. Though still small, J/ψ production may be observable in present and future experiments such as NuTeV and μ colliders. ©2001 The American Physical Society.

Enhancement of Corrosion Resistance AISI 304 Steel by Plasma Polymerized Thin Films

The purpose of this work is the deposition of films in order to increase the corrosion resistance of AISI 304 steel, which is a material used to construct the reactors for bioethanol production. This deposition inhibits the permeation of corrosive species to the film-metal interface. Thin films were prepared by radio-frequency plasma enhanced chemical vapor deposition (RF-PECVD) method using plasmas of hexamethyldisiloxane/argon/oxygen mixtures excited by signals of different powers. The plasma was generated by the application of RF power of 13.56 MHz to the sample holder while keeping grounded the topmost electrode and the chamber walls. The effect of the RF power on the properties of the samples was investigated by perfilometry, X-ray photoelectron spectroscopy (XPS), contact angle, and electrochemical impedance spectroscopy (EIS). The results of the corrosion resistance tests of the AISI 304 steel were interpreted in terms of the energy delivered to the growing layer by plasma excitation power.

Possibilidades e limites de experiência: imagem e formação de professoras de infância da rede pública de Rio Claro

Pós-graduação em Educação - IBRC

Impacto da municipalização do ensino fundamental público sobre as condições de trabalho dos professores no município de Presidente Prudente-SP

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

O IDEB como política de regulação do Estado e legitimação da qualidade: em busca de significados

Abstract This paper discusses the quality of basic education legitimized by the external evaluation and publicized by the Basic Education Development Index (IDEB) - an index that combines the performance of students in the assessment and the school flow, culminating with the establishment of an objective parameter (grade) that aims to reflect the Brazilian educational quality. The arguments are based on the premise that these two elements are incipient to determine the quality of education in the country without taking into account other factors that affect quality, namely: socio-economic and cultural level of the students, teacher training, enhancement of teaching, tangible and intangible working conditions, school management, school infrastructure, supplies, etc. The reflection leading to the debate on the lack of evidence to establish the quality of education travels the ways of the external evaluation in Brazil, the technical rationality of the school management referenced primarily by the IDEB and its governance to achieve the goals determined by this index. The purpose of this essay is to contribute to the current debate on the IDEB as a proposer and mobilizer of policies for the Brazilian public schools.

O olhar de um discente sobre seu futuro docente: uma trajetória auto formativa

The writings of this paper refer to several personal experiences as well as the various conflicts in the initial educational formation, where I'm reflecting about the formation intentions of this course. I do an analysis and a reflection of the pedagogical practices developed during graduation in institutional spaces, as well as the understanding of the complex context and teaching actions intrinsic to this, that are what constitute the structural dimensions which is where the formative process happens. This study is a narrative of initial formation as autobiographical. Memories and experiences are analyzed along with undergraduate education, exposing structural problems of course requiring a deeper analysis. In addition to analyse critically the institutional spaces of the (few) outreach programs, education and research that are the basis of the Brazilian University, the wellknown University quadripod. Under this perspective, the narrative brings the dichotomous design of the quadripod inside the University course, exposing the need to reflect on this fact, as it culminates in the formation of future teachers in physics. Nevertheless, the work seeks to raise awareness for the need for enhancement of teaching career at the University to address the teaching crisis which today proliferates in the educational institutions in Brazil, therefore it is necessary to the teachers to become aware of your profession and the vision as such. Only from this perspective one can discuss a proper teacher training, aiming at the integration of all activities, valuing all with the same importance

Blue upconversion enhancement by a factor of 200 in Tm 3+-doped tellurite glass by codoping with Nd 3+ ions

We investigated near-infrared-to-blue upconversion from thulium (Tm 3+) doped in tellurite glasses upon continuous wave excitation near 800 nm. We observed an enhancement of over two orders of magnitude of the upconverted emission at ∼480nm when neodymium (Nd 3+) ions were codoped with Tm 3+ ions. For comparison, using a Tm 3+:Nd 3+ codoped fluorozirconate glass as a reference material we observed a 40-fold enhancement of the blue emission. Analysis of the blue emission for samples with different doping levels of Nd 3+ ions showed that energy transfer between Nd 3+ and Tm 3+ is the mechanism responsible for the enhancement in upconversion. © 2002 American Institute of Physics. © 2002 American Institute of Physics.

Pedagogical practices carried out during an in-service teachers education project: approaching history and philosophy of science to physics teaching

We report here part of a research project developed by the Science Education Research Group, titled: "Teachers’ Pedagogical Practices and formative processes in Science and Mathematics Education" which main goal is the development of coordinated research that can generate a set of subsidies for a reflection on the processes of teacher training in Sciences and Mathematics Education. One of the objectives was to develop continuing education activities with Physics teachers, using the History and Philosophy of Science as conductors of the discussions and focus of teaching experiences carried out by them in the classroom. From data collected through a survey among local Science, Physics, Chemistry, Biology and Mathematics teachers in Bauru, a São Paulo State city, we developed a continuing education proposal titled “The History and Philosophy of Science in the Physics teachers’ pedagogical practice”, lasting 40 hours of lessons. We followed the performance of five teachers who participated in activities during the 2008 first semester and were teaching Physics at High School level. They designed proposals for short courses, taking into consideration aspects of History and Philosophy of Science and students’ alternative conceptions. Short courses were applied in real classrooms situations and accompanied by reflection meetings. This is a qualitative research, and treatment of data collected was based on content analysis, according to Bardin [1].