Characterization of natural rubber/gold nanoparticles SERS-active substrate

Natural rubber/gold nanoparticles membranes (NR/Au) were studied by ultrasensitive detection and chemical analysis through surface-enhanced Raman scattering and surface-enhanced resonance Raman scattering in our previous work (Cabrera et al., J. Raman Spectrosc. 2012, 43, 474). This article describes the studies of thermal stability and mechanical properties of SERS-active substrate sensors. The composites were prepared using NR membranes obtained by casting the latex solution as an active support (reducing/establishing agents) for the incorporation of colloidal gold nanoparticles (AuNPs). The nanoparticles were synthesized by in situ reduction at different times. The characterization of these sensors was carried out by thermogravimetry, differential scanning calorimetry, scanning electron microscopy (SEM) microscopy, and tensile tests. It is suggested an influence of nanoparticles reduction time on the thermal degradation of NR. There is an increase in thermal stability without changing the chemical properties of the polymer. For the mechanical properties, the tensile rupture was enhanced with the increase in the amount of nanoparticles incorporated in the material. © 2013 Wiley Periodicals, Inc.

Estimativas da radiação global incidente em superfícies inclinadas com base na razáo de insolação

Estimating equations of global radiation based on the sunshine duration were proposed for horizontal surface and with inclination of 12.85, 22.85 and 32.85° facing the North in Botucatu, SP, Brazil, in monthly, seasonal and annual groupings of data. Simple linear correlations were applied (for definition of the linear and angular coefficients of Angstrom-Prescott model), in a database measured in all three inclinations in different periods (22.85°: 04/1998 to 07/2001; 12.85°: 08/2011 to 02/2003; and 32.85°: 03/2003 to 12/2007) concomitant with horizontal measures and sunshine duration. The statistical performance of the model was analysed by the means absolute error (MBE), the square root of the mean square error (RMSE) and the index adjustment (d). The minimum global radiation transmissivity varied from 14.35% in August (12.85°) to 27.86% in December (32.85°) and the maximum transmissivity ranged between 62.10% and 78.90%, for June (32.85°) and December (12.85°). Increasing the angle of inclination surface increased the scattering and decreased the index of adjustment and performance. The worst results were found for application of the seasonal and annual models in the months of autumn and winter for 32.85° (RMSE below 42.93% and adjustment superior to 0.4693).

Estimativas das radiações direta e difusa em superfícies inclinadas com base na razáo de insolação

Statistical equations were obtained and evaluated with annual, seasonal and monthly data groupings for estimates of direct and diffuse components of solar radiation based on the sunshine duration (ratio of sunshine and photoperiod) incident on horizontal and inclined surfaces to 12.85, 22.85 and 32.85° with facing to North, in Botucatu, SP. The ratios between the two components and radiation at the top of the atmosphere were used, in a database whose inclinations were measured in three different periods (22.85°: 04/1998 to 07/2001; 12.85°: 08/2011 to 02/2003; and 32.85°: 03/2003 to 12/2007) and concomitant with horizontal measures and sunshine duration. The correlations showed a linear and second degree polynomial behavior for the direct and diffuse radiation, with higher coefficients of determination in periods of low variation in the coverage of the sky (cloudiness). The highest values of the direct and diffuse radiation were found in winter and summer, respectively for all surfaces evaluated. The increase in the inclination angle decreased the performance of equations in all groups of data with increase in scattering and decrease in index of the adjustment, however, the monthly equations allowed better performance for the two components.

Sistemas drug delivery aplicados a novos inibidores de topoisomerases estruturalmente derivados de toxinas bacterianas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo das propriedades físicas de blendas de PVDF/Látex visando aplicação como biomaterial

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo da arquitetura molecular de filmes layer-by-layer de ftalocianina tetrasulfonada de cobre

Pós-graduação em Ciência e Tecnologia de Materiais - FC

Ciprofloxacino encapsulado em lipossomas revestidos com ácido poli láctico co-glicólico ou veiculado em gel de copolímero de bloco Pluronic R F127

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação do efeito do praziquantel veiculado em dispersões lipídicas no tratamento de camundongos infectados com schistosoma mansoni

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Síntese, caracterização e estudo físico-químico das nanopartículas formadas pela interação de amino derivados de quitosana com DNA

Pós-graduação em Química - IBILCE

Caracterização por espectroscopia vibracional de filmes Layer-by-Layer contendo ftalocianina, polímeros condutores e gomas naturais

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

Identificação de pigmentos em artefatos arqueológicos via espectroscopia Micro-Raman

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

Síntese, caracterização e estudo físico-químico de nanopartículas formadas pela interação de derivados hidrofílicos de quitosana com DNA

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Estudo da formação de microemulsões em misturas de surfactante/óleos vegetais e interação com vitaminas e sais

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

Quantização funcional e renormalizabilidade da eletrodinâmica generalizada

Pós-graduação em Física - IFT

Filmes nanoestruturados aplicados ao sistema de língua eletrônica: um estudo de interfaces

Pós-graduação em Ciência e Tecnologia de Materiais - FC