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Patients in real life may differ from those in clinical trials. The aim of this study is to report 5-year outcomes of a continuous treat-to-target (T2T) approach in patients with rheumatoid arthritis (RA) in daily clinical practice. In the Dutch RhEumatoid Arthritis Monitoring cohort, all patients with a clinical diagnosis of RA were treated according to a protocolled T2T strategy, aimed at 28-joint Disease Activity Score (DAS28) < 2.6. Outcomes were percentages of patients in distinct levels of disease activity, mean course of DAS28 and prevalence of sustained (drug-free) remission. Also, data on functional disability (Health Assessment Questionnaire) and health-related quality of life (Short-Form 36) were examined. Mean DAS28 improved from 4.93 (95% CI 4.81-5.05) at baseline to 2.49 (95% CI 2.35-2.63) after 12 months and remained stable thereafter. Percentages of patients at 12 months with DAS28 < 2.6 (remission), DAS28 ≥ 2.6 and ≤ 3.2 (low disease activity), DAS28 > 3.2 and ≤ 5.1 (moderate disease activity) and DAS28 > 5.1 (high disease activity) were 63, 16, 18 and 3%, respectively. Sustained remission (DAS28 < 2.6 during ≥ 6 months) was observed at least once in 84% of the patients and drug-free remission (DAS28 < 2.6 during ≥ 6 months after withdrawal of all disease-modifying anti-rheumatic drugs) in 36% of the patients. Functional disability and health-related quality of life significantly improved during the first 24 weeks. Continuous application of T2T in real-life RA patients leads to favourable disease- and patient-related outcomes. [ABSTRACT FROM AUTHOR]

The mass transfer rates of a gaseous reactant into a liquid where the reactions are catalyzed by homogeneous catalysts have been evaluated by the numerical solution of the diffusion-reaction equations according to Higbie's penetration theory. The concentration profiles as well as enhancement factors are discussed as functions of the kinetic rate constants and the diffusion coefficients of the catalytic intermediates. In addition to the complex catalytic model, two simplified models were applied in order to facilitate design calculations. One version was obtained by application of the Bodenstein approximation; the simplest version comprised only the stoichiometric reaction. The Bodenstein model provides a very good approximation except for deviating diffusion coefficients of the catalytic intermediates. The applicability of the stoichiometric model is not as wide as with the Bodenstein model, but for some conditions acceptable approximations are achieved. [ABSTRACT FROM AUTHOR]

In the present work, new experimental data are presented on the solubility of carbon dioxide in aqueous piperazine solutions, for concentrations of 0.2 and 0.6 molar piperazine and temperatures of 25, 40, and 70°C respectively. The present data, and other data available in the literature, were correlated using a model based on the electrolyte equation of state (EoS), as originally proposed by Fürst and Renon. The final model derived, containing only seven adjustable (ionic) parameters, was able to describe the available experimental solubility data (>150 data points for total and/or CO2 partial pressure) with an average deviation of 16%. [ABSTRACT FROM AUTHOR]

The kinetics of the forward polycondensation reaction of polybutylene terephthalate (PBT) has been investigated using thermogravimetric analysis (TGA). PBT - prepolymer with an initial degree of polymerization of 5.5 was used as starting material. The PBT prepolymer was prepared from dimethyl terephthalate (DMT), and 1,4 - butanediol with 470 ppm wt (with respect to DMT) of tetrabutoxytitanate as catalyst. The process conditions in the TGA were such that the weight loss curves obtained from the TGA could be correlated uniquely and directly to the forward polycondensation reaction kinetics due to the absence of (1) mass transfer limitations in the removal of 1,4 butanediol from the melt, and (2) degradation reactions. It is shown that in the temperature range of 230-270°C, the forward polycondensation reaction can be expressed using second-order kinetics in terms of the hydroxyl end group concentration of the PBT polymer. [ABSTRACT FROM AUTHOR]

A technique is developed for measurement of bubble, droplet and particle-size distributions in multiphase systems, based on the propagation speed and attenuation of ultrasound. The measurement of the size distribution of the dispersed phase in multiphase systems was desired to analyze the mass-transfer mechanism in gas-liquid-liquid and gas-liquid-solid systems. To obtain this information, both the ultrasonic velocity and the attenuation coefficient of tone-burst signals are determined for a large frequency range (typically 100 kHz - 100 MHz). From these parameters, the size distributions and the volume fraction of the different dispersed phases can be determined using a scattering model. It was shown that the interfacial area can be determined very accurately, however, for the exact size distribution of the gas bubbles in the used size range (1-3 mm) an independent gas holdup determination is required. Experiments were performed in gas-liquid, solid-liquid, and gas-liquid-solid systems. The results showed good agreement of the particle-size distribution compared to a commercial laser-scattering analyzer, both with and without gas bubbles present. Furthermore, a good agreement between the scattering model and the experiments was found in the systems that contained gas bubbles, but these results should be validated using for instance, a digital camera technique. [ABSTRACT FROM AUTHOR]

Several organic impurities formed in the p-xylene oxidation process for manufacture of terephthalic acid are carried into the aqueous effluent from the crystallization section of PTA plant of crystallizers for purified terephthalic acid (PTA). These compounds impose a burden on the effluent treatment plant. Due to the presence of these impurities the recycle of aqueous effluent from crystallization section of PTA plant to the PTA crystallizer is not possible. The aim of this study is to check the feasibility of removal of these organic impurities from the aqueous effluent from crystallization section of PTA plant by adsorption on polymeric resins so that the aqueous effluent from crystallization section of PTA plant can be recycled resulting in significant saving of process water. Aqueous effluent from crystallization section of PTA plant was characterized and single solute and multisolute adsorption equilibria of the compounds present were determined for a variety of polymeric adsorbents. Column breakthrough study has shown that the components can be removed and recovered from the aqueous effluent from the crystallization section of PTA plant by adsorption. [ABSTRACT FROM AUTHOR]