Grafting of adipic anhydride to carbon nanotubes through a Diels-Alder cycloaddition/oxidation cascade reaction

Accepted Manuscript

Modelação, simulação e implementação de agitação acústica para aplicações em microfluídica

Tese de Doutoramento (Programa Doutoral em Engenharia Biomédica)

Validação preliminar de uma versão do Caregiver Reaction Assessment em um contexto de pacientes oncológicos em internação

Objetivo Adaptar para o Brasil uma versão portuguesa do Caregiver Reaction Assessment (CRA) e gerar indicadores preliminares de validade e fidedignidade para sua aplicação em cuidadores de pacientes oncológicos internados. Métodos Participaram voluntariamente 53 cuidadores, que responderam a um questionário sociodemográfico, ao CRA e à Escala de Bem-Estar Psicológico (EBEP). A unidimensionalidade e a homogeneidade dos escores do CRA foram avaliadas por meio de análise de componentes principais e de consistência interna, respectivamente. Correlações de Pearson entre escores do CRA e EBEP foram examinadas e utilizadas como indicadores de validade divergente e de construto. Resultados As cinco escalas que compõem o CRA apresentaram bons níveis de unidimensionalidade e homogeneidade, porém as escalas de impacto nas finanças e impacto na saúde obtiveram alfas insuficientes (< 0,7). O escore total do CRA apresentou alfa elevado (0,886). Correlações entre o CRA e a EBEP produziram coeficientes teoricamente interpretáveis, com magnitudes variando entre nulas e moderadas. Conclusão O CRA apresentou bons indicadores de validade e fidedignidade. Algumas adaptações em relação ao conteúdo de determinados itens se mostram, todavia, necessárias, a fim de serem calibradas ao contexto de pessoas atendidas por serviços subsidiados pelo Sistema Único de Saúde.

Force elements and reaction forces

"Series title: Springerbriefs in applied sciences and technology, ISSN 2191-530X"

A multi–physics approach applied to masonry structures with non–hydraulic lime mortars

Tese de Doutoramento em Engenharia Civil (área de especialização em Engenharia de Estruturas).

Separation by thermal diffusion in a rotary column

A rotary thermal diffusion column with the inner cylinder rotating and the outer cylinder static was used to separate n-heptane-benzene mixtures at different speeds of rotation. The results show that the column efficiency depends on the speed of rotation. For the optimum speed the increase in efficiency relative to the static column was of the order of 8%. The role of the geometric irregularities in the annulus width on performance of the rotary column is also discussed.

Nonsymmetrical separations in thermal diffusion columns

The influence of the feed composition upon the actual degrees of separation attained at the top and bottom sections of a thermogravitational column is discussed using the classical phenomenological theory of Furry, Jones, and Onsager. It is shown that, except for a feed composition of C 0 = 0.5 (mass fraction), the separation profile is nonsymmetric, i.e., the separations in the top and bottom sections of the column are nonsymmetric with respect to the feed composition, the asymmetry increasing as the feed composition moves away from C 0 = 0.5. An equation for the determination of the optimum feed location as a function of the feed composition is derived.

Some observations on asymmetrical separation in thermal diffusion columns

Data have been obtained in steady-state batch operated thermogravitational separation columns using different binary mixtures to test the theory recently published by Morgado et al. The experimental results confirm that separations by thermal diffusion are asymmetrical except when the initial concentration is 0.5 and that the asymmetry is larger as the initial concentration deviates from 0.5 and as the separation potential increases.

The application of the equivalent annulus width concept in thermal diffusion separations

The equivalent annulus width concept is used to characterize a small commercial thermogravitational hermal diffusion column and its validity checked experimentally by separating batchwise in the column mixtures of n-heptanebenzene with different initial concentrations. The equation of Ruppell and Coull was used to analyse the data in the short separation times range and determine the equivalent annulus width. Good agreement was obtained between the experimental and predicted time-separation curves when using the equivalent annulus width value and on averaged value of the thermal diffusion constant. A new method is presented for the simultaneous determination of the equivalent annulus width and the thermal diffusion constant of a binary mixture from a single set of experimental data.

Single molecule simulation of diffusion and enzyme kinetics

This work presents a molecular-scale agent-based model for the simulation of enzymatic reactions at experimentally measured concentrations. The model incorporates stochasticity and spatial dependence, using diffusing and reacting particles with physical dimensions. We developed strategies to adjust and validate the enzymatic rates and diffusion coefficients to the information required by the computational agents, i.e., collision efficiency, interaction logic between agents, the time scale associated with interactions (e.g., kinetics), and agent velocity. Also, we tested the impact of molecular location (a source of biological noise) in the speed at which the reactions take place. Simulations were conducted for experimental data on the 2-hydroxymuconate tautomerase (EC 5.3.2.6, UniProt ID Q01468) and the Steroid Delta-isomerase (EC 5.3.3.1, UniProt ID P07445). Obtained results demonstrate that our approach is in accordance to existing experimental data and long-term biophysical and biochemical assumptions.

Lang anhaltende Prozesse der retinalen Spreading Depression : Untersuchung des intrinsischen optischen Signals

Excitability, wave, reaction-diffusion, chicken, neuron, glia, potassium, nitric oxide, glycolysis

Adaptive Verfahren zur numerischen Berechnung von Reaktions-Diffusions-Systemen

Reaction-diffusion problems, finite elements, unstructured grid, grid adaption, W-method, stiffness, local partitioning, excitable medium, spiral wave drift

Convex and toric geometry to analyze complex dynamics in chemical reaction systems

Convex cone, toric variety, graph theory, electrochemical catalysis, oxidation of formic acid, feedback-loopsbifurcations, enzymatic catalysis, Peroxidase reaction, Shil'nikov chaos

Theory and application of nonlinear wave propagation phenomena in combined reaction/separation processes

Reaction separation processes, reactive distillation, chromatographic reactor, equilibrium theory, nonlinear waves, process control, observer design, asymptoticaly exact input/output-linearization