GLOBAL DYNAMICS of THE LORENZ SYSTEM WITH INVARIANT ALGEBRAIC SURFACES

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Inclusion complex of piroxicam with beta-cyclodextrin and incorporation in hexadecyltrimethylammonium bromide based microemulsion

The interaction of piroxicam with beta-cyclodextrin (beta-CD), hexadecyltrimethylammonium bromide-based microemulsion (ME), and ME in the presence of beta-CD aimed at the optimization of topical drug delivery was studied. UV-VIS absorption spectra at pH 5.5 were obtained with and without beta-CD and ME. The stability constant (K) values for the piroxicam/beta-CD complex in the pH range 4.5-6.0 varied from 87 to 29 M-1. The cationic microemulsion was characterized by pseudo-ternary phase diagram. The association constant (K-s) of piroxicam/ME was determined using the framework of the pseudophase model. The value of K-s obtained for piroxicam at pH 5.5 was 132 M-1. At the same pH, the value of K-s for the incorporation of piroxicam/beta-CD complex in the ME was 150 M-1. (C) 1999 Elsevier B.V. B.V. All rights reserved.

Physicochemical Characterization and Development of a Microemulsion System for Transdermal Use

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Prospective study for the development of emulsion systems containing natural oil products

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Microemulsões e fases líquidas cristalinas como sistemas de liberação de fármacos

A mistura de tensoativos com água, em determinadas proporções, na ausência ou na presença de substâncias lipofílicas pode formar diferentes tipos de agregados, entre os quais agregados polimorfos representados pelas microemulsões (ME) e mesofases liotrópicas - os cristais líquidos (LC), que estão intimamente ligados com a proporção e a natureza dos componentes da mistura. Nesse trabalho, foi discutido o papel desses sistemas na incorporação de fármacos com diferentes propriedades físico-químicas, influenciando fortemente a liberação, assim como a biodisponibilidade dos fármacos. Aspectos sobre a formação e a caracterização de microemulsões e cristais líquidos também foram discutidos. A análise da literatura indicou que, dependendo da polaridade do fármaco, o efeito da ME ou LC pode ser usado para otimizar o efeito terapêutico por meio do controle da velocidade ou do mecanismo de liberação do fármaco.

Analysis of the molecular association of rifampicin with hydroxypropyl-²-cyclodextrin

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

Effect of cosurfactant on the supramolecular structure and physicochemical properties of non-ionic biocompatible microemulsions

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

GRAPHICAL REPRESENTATIONS of MESSAGE EXCHANGES INTO WEB SERVICE-BASED APPLICATIONS

Web service-based application is an architectural style, where a collection of Web services communicate to each other to execute processes. With the popularity increase of Web service-based applications and since messages exchanged inside of this applications can be complex, we need tools to simplify the understanding of interrelationship among Web services. This work present a description of a graphical representation of Web service-based applications and the mechanisms inserted among Web service requesters and providers to catch information to represent an application. The major contribution of this paper is to discus and use HTTP and SOAP information to show a graphical representation similar to a UML sequence diagram of Web service-based applications.

Anelastic spectroscopy in SmBa2Cu3O7

The possibility of variable stoichiometry and the high mobility of oxygen in the CuOx planes of SmBa2Cu3O7 give rise to a rich phase diagram. Measurements of the elastic energy loss and modulus (anelastic spectroscopy) as a function of temperature can distinguish among the different atomic jumps, which occur in the various phases or at different local ordering. In this paper, it is reported anelastic relaxation measurements in SmBa2Cu3O7, above room temperature, using a torsion pendulum operating in frequencies around 40 Hz. The mobility of oxygen atoms in the CuOx planes in the various phases has been discussed and the thermally activated peak of elastic energy dissipation observed around 500 K was interpreted in that framework. (C) 2004 Elsevier B.V. All rights reserved.

Mobilidade de oxigênio intersticial em cerâmicas SmBa2Cu3O7-delta

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

Superconducting boundary conditions for mesoscopic circular samples

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

Magnetic interactions and spin-reversal mechanism in ErMn1-xCoxO3-delta samples

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

Oxygen dynamics and the effects of heat treatments in SBCO samples investigated by mechanical spectroscopy

The compound SmBa(2)Cu(3)O(7-delta) (SBCO)-obtained by substituting rare-earth Sm for Y in the well-known and most studied YBa(2)Cu(3)O(6+delta) (YBCO)-is potentially attractive to study in order to understand the superconductivity mechanism in physics and in electronic device applications. For SBCO, the possibility of variable stoichiometry and the high mobility of oxygen in CuO(x) planes give rise to a rich phase diagram. This study reports on the effect of heat treatments in an oxygen atmosphere on the anelastic properties of this oxide, in which relaxation processes were observed, attributed to oxygen atom jumps present in the Cu-O planes during the orthorhombic phase.

Kondo-attractive-Hubbard model for the ordering of local magnetic moments in superconductors

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

Incommensurate spin-density-wave and metal-insulator transition in the one-dimensional periodic Anderson model

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