Estudo da remobilização de metais de sedimentos contaminados na bacia hidrográfica do Rio Minho

Tese de mestrado integrado. Engenharia Quimica. Universidade do Porto. Faculdade de Engenharia. 201

Separation of gaseous mixtures (Nitrogen-MJethane-Carbon dioxide) by adsorption usig titanosilicate ETS-4

Tese de mestrado integrado. Engenharia Quimica. Faculdade de Engenharia. Universidade do Porto. 201

Optimização da produção do nitrobenzeno e da anilina

Estágio realizado na CUF-Químicos Industriais, S. A., e orientado pelo Doutor Alejandro RibeiroTese de mestrado integrado. Engenharia Quimica. Universidade do Porto. Faculdade de Engenharia. 201

Microencapsulation of limonen oil for textile application

The production of polyurethane-urea microcapsules using the interfacial polymerization technology was performed. Microcapsules were produced in a basic IKA® Miniplant laboratory reactor, in order to produce microcapsules with controlled parameters. In this formulation, limonene, a fragrant chemical characteristic of the lemon oil - was microencapsulated, because lemon oil is the most used oil in perfumery. It resulted in microcapsules with bimodal distribution and average size equal to 10µm. The characterisation of the microcapsules includes particle size distribution, optical microscopy and scanning electron microscopy. Using scanning electron microscopy it is visible the presence of well defined microcapsules on the woven.Project SCENTFASHION, contract ADI/2004/M2.3/0015POCI funded by Agência de Inovação(AdI) in the framework of POCI 2010-Medida 2.3-IDEIA

High magnetic field induced charge density wave states in a quasi-one dimensional organic conductor

We have measured the high field magnetoresistence and magnetization of quasi-one- dimensional (Q1D) organic conductor (Per)2Pt(mnt)2 (where Per = perylene and mnt = maleonitriledithiolate), which has a charge density wave (CDW) ground state at zero magnetic field below 8 K. We find that the CDW ground state is suppressed with moderate magnetic fields of order 20 T, as expected from a mean field theory treatment of Pauli effects[W. Dieterich and P. Fulde, Z. Physik 265, 239 - 243 (1973)]. At higher magnetic fields, a new, density wave state with sub-phases is observed in the range 20 to 50 T, which is reminiscent of the cascade of field induced, quantized, spin density wave phases (FISDW) observed in the Bechgaard salts. The new density wave state, which we tenatively identify as a field induced charge density wave state (FICDW), is re-entrant to a low resistance state at even higher fields, of order 50 T and above. Unlike the FISDW ground state, the FICDW state is only weakly orbital, and appears for all directions of magnetic field. Our findings are substantiated by electrical resistivity, magnetization, thermoelectric, and Hall measurements. We discuss our results in light of theoretical work involving magnetic field dependent Q1D CDW ground states in high magnetic fields [D. Zanchi, A. Bjelis, and G. Montambaux, Phys. Rev. B 53, (1996)1240; A. Lebed, JETP Lett. 78,138(2003)].Comment: 16 pages, 5 figure

Adsorption and separation of CO2/CH4 on binderless beads of 13X zeolite

The sorption equilibrium of CO2 and CH4 has been investigated on the binderless beads of 13X zeolite between 313 and 373 K and pressure up to 4 atm. The amount adsorbed of CO2 and CH4 is around 5.2 mmol/gads and 1.2 mmol/gads, respectively, at 313 K and 4 atm. Comparing these values with the ones in literature the value of CO2 is 20% higher than in similar 13X binder pellets

Catalytic reutilization of chromium-loaded NaY oxidation of ethyl acetate

EUROPACAT IX - Catalysis for a Sustainable WorldThe aim of this study is the reutilization of new materials obtained by biorecovery of chromium from water, in catalytic oxidations of volatile organic compounds. A biosorption system consisting of a microorganism supported on a NaY zeolite was used to remove hexavalent chromium from contaminated water. After the biosorption process, the chromium-loaded zeolite was used as catalyst to be applied in catalytic oxidation of ethyl acetate. The results showed that a higher content of chromium enhanced the activity and the C0 2 selectivity of the catalystinfo:eu-repo/semantics/publishedVersio