Self-organizing neural networks for modeling robust 3D and 4D QSAR: application to dihydrofolate reductase inhibitors

We have used SOM and grid 3D and 4D QSAR schemes for modeling the activity of a series of dihydrofolate reductase inhibitors. Careful analysis of the performance and external predictivities proves that this method can provide an efficient inhibition model

Catalytic azo dye reduction in advanced anaerobic bioreactors

En un reactor anaeróbico de lecho empacado y de flujo ascendente con carbón activado (AC) biológico se obtuvieron altas velocidades de conversión del colorante azoico Acid Orange 7 a tiempos espaciales muy cortos, hasta 99% en 2.0 min. Tanto el área superficial específica como la conductividad electrónica del AC contribuyeron a las mayores velocidades de reducción. La agitación en el lecho de carbón produjo un incremento de la bioconversión del colorante. Se estableció un modelo cinético de decoloración que implica catálisis heterogénea y bioreducción. La biodegradabilidad anaeróbica de un colorante azoico en el sistema reactivo agitado pudo ser predicha a partir de su potencial de reducción. Las velocidades de decoloración fueron significativamente influenciadas por las propiedades texturales del AC y moderadamente afectadas por su química superficial. Este bioreactor catalítico parece ser una alternativa atractiva para la mejora económica de las tecnologías de tratamiento de aguas residuales textiles y de colorantes.In an anaerobic upflow packed-bed reactor with biological activated carbon (AC), high azo dye Acid Orange 7 conversion rates were achieved during very short space times up to 99% in 2.0 min. Both electron conductivity and specific surface area of AC contributed to higher reduction rates. The application of stirring in the carbon bed resulted in an increase of dye bioconversion. A decolourisation model was developed involving both heterogeneous catalysis and bioreduction. The anaerobic biodegradability of an azo dye could be predicted by its reduction potential in the stirred reactor system. The decolourisation rates were found to be significantly influenced by the textural properties of AC and moderately affected by its surface chemistry. This catalytic bioreactor system seems to be an attractive alternative for economically improving textile/dye wastewater technologies

Sektorowy formalizm porównawczej analizy powierzchni cząsteczkowej (s-CoMSA) - zastosowanie do modelowania zależności struktura-aktywność

Celem pracy jest: Opracowanie nowej metody obliczania deskryptorów cząsteczkowych s-CoMSA (ang. sector-comparative molecular surface analysis); w metodzie tej przestrzeń cząsteczkowa jest dzielona za zbiór sześciennych sektorów, ● Szeroko rozumiana optymalizacja metody s-CoMSA, ● Analiza QSAR oraz SAR wybranych szeregów związków aktywnych biologicznie z wykorzystaniem metody s-CoMSA oraz innych metod 3D-QSAR. W zakres pracy wchodzi: Opracowanie formalizmu metody s-CoMSA, ● Zaprogramowanie procedur analizy s-CoMSA, ● Badanie modeli s-CoMSA aktywności biologicznej wybranych szeregów związków organicznych, w tym: • szeregu steroidów o powinowactwie do globuliny wiążącej kortykosteroidy (ang. corticosteroid-binding globulin – CBG), • inhibitorów wirusa HIV, • inhibitorów reduktazy kwasu dihydrofoliowego

Degradation of dye-containing textile effluents by enzymatic catalysis

Tese de doutoramento. Engenharia Química. Faculdade de Engenharia. Universidade do Porto. 201

Exploitation of ZnO/Fe3O4 and TiO2/Fe3O4 nanocomposites on the degradation of organic compounds

Water is the main sources for all living beings. However, with the vast development and advancement of technology, water resources have been seriously contaminated by industries effluent, especially organic dyes. Various methods have been implemented to achieve certain level of acceptable cleanliness. Current most efficient and cost effective process is the photocatalytic process using highly photoreactive ZnO and TiO2 semiconductors. However, separation of the semiconductor powder arises at the end of the decomposition process. Therefore, there have been many researches trying to dope magnetic material into the semiconductor to make it easily separable and cost effective by just applying a magnetic field. However, most of the preparations require various recalcitrant and toxicant precursor chemicals as well as high sintering temperature. In light of these, this study has tried to use simple method of preparation and followed by a significantly moderate sintering temperature. The ZnO/Fe3O4 and TiO2/Fe3O4 nanocomposite materials have been successfully prepared by simple mechanical mixing and sintered at significantly moderate temperature of 300 and 350 oC, respectively. Besides, the prepared nanocomposite exhibit remarkable photocatalytic decomposition on few chosen dyes. The XRD results indicated a good crystallinity with the standard for both nanocomposites. The SEM and TEM results showed ZnO/Fe3O4 nanocomposite was square-like and elongated in shape, whiles it was mostly spherical for TiO2/Fe3O4 nanocomposite. VSM measurements showed that both nanocomposites exhibit ferromagnetism, while ZnO and TiO2 are diamagnetism in nature. Both nanocomposites able to completely decomposed the MB dye. All the photocatalytic measurements show that the photodegradation processes are following the pseudo-first-order kinetics. Both nanocomposites were successfully magnetically separated from the decomposed solution by using a 0.60 T permanent magnet. A 9.0wt% loading of ZnO/Fe3O4 nanocomposite with 10wt% doped Fe3O4 and sintered at 300 oC was able to completely decomposed MB in 30 minutes (99.9%) with kinetic constant of 0.242 min–1. On the other hand, TiO2/Fe3O4 nanocomposite with 1wt% doped Fe3O4 sintered at 350 oC and at optimum loading of 3wt% was able to decompose 98.7% of MB in 60 minutes with kinetic constant of 0.0729 min–1. The repeatability experiments were conducted and the results indicated that there was a minor deactivation (~1.08%) after the second and third run. This shows that both nanocomposites were photocatalytically stable and reusable for wider application on organic dyes decomposition. The effect of the intrinsic properties for the chosen organic dyes, such as their azo groups, benzene groups, molecular weight and absorbance, in relation to their rate of decomposition were evaluated in the last part of this study. The results show that the degradation rate is linearly proportional to the number of azo groups, the number of benzene groups, the molecular weight and inversely proportional to the absorbance of the dye’s solution

Synthesis and Characterization of Pharmacologically Active Compounds

Not availabl

Coumarin and Its Derivatives

Coumarins are widely distributed in nature and can be found in a large number of naturally occurring and synthetic bioactive molecules. The unique and versatile oxygen-containing heterocyclic structure makes them a privileged scaffold in Medicinal Chemistry. Many coumarin derivatives have been extracted from natural sources, designed, synthetized, and evaluated on different pharmacological targets. In addition, coumarin-based ion receptors, fluorescent probes, and biological stains are growing quickly and have extensive applications to monitor timely enzyme activity, complex biological events, as well as accurate pharmacological and pharmacokinetic properties in living cells. The extraction, synthesis, and biological evaluation of coumarins have become extremely attractive and rapidly developing topics. A large number of research and review papers have compiled information on this important family of compounds in 2020. Research articles, reviews, communications, and concept papers focused on the multidisciplinary profile of coumarins, highlighting natural sources, most recent synthetic pathways, along with the main biological applications and theoretical studies, were the main focus of this book. The huge and growing range of applications of coumarins described in this book is a demonstration of the potential of this family of compounds in Organic Chemistry, Medicinal Chemistry, and different sciences related to the study of natural products. This book includes 23 articles: 17 original papers and six review papers

Water Quality Engineering and Wastewater Treatment

Clean water is one of the most important natural resources on earth. Wastewater, which is spent water, is also a valuable natural resource. However, wastewater may contain many contaminants and cannot be released back into the environment until the contaminants are removed. Untreated wastewater and inadequately treated wastewater may have a detrimental effect on the environment and has a harmful effect on human health. Water quality engineering addresses the sources, transport and treatment of chemical and microbiological contaminants that affect water. Objectives for the treatment of wastewater are that the treated wastewater can meet national effluent standards for the protection of the environment and the protection of public health. This book, which is based on the Special Issue, includes contributions on advanced technologies applied to the treatment of municipal and industrial wastewater and sludge. The book deals with recent advances in municipal wastewater, industrial wastewater, and sludge treatment technologies, health effects of municipal wastewater, risk management, energy efficient wastewater treatment, water sustainability, water reuse and resource recovery

Proceedings of the 10th International Chemical and Biological Engineering Conference - CHEMPOR 2008

This volume contains full papers presented at the 10th International Chemical and Biological Engineering Conference - CHEMPOR 2008, held in Braga, Portugal, between September 4th and 6th, 2008.FC