Anne M. Garrido Pedrosa

Pechini synthesis and microstructure of nickel-doped copper chromites

Spinel-type solid solutions were synthesized by the Pechini method and calcined between 500 and 900 °C for 4 hours and at 900 °C for 8 hours to produce ceramic pigments. The resulting powders were characterized by thermogravimetric analysis, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), particle size analysis and BET surface area measurements. The formation of spinel took place upon calcination at 700 °C. IR spectroscopy revealed the presence of n1 and n2 bands, typical of spinel structures, broadened by the presence of more than one cationic species in the structure. The specific area of the resulting powder decreased from 24.7 to 1.4 m2 g-1 as the calcination temperature increased from 700 to 900 °C. Microstructural analyses revealed the presence of crystalline spinel as the only phase present in powders calcined at 900 °C. Colorimetric analyses using L*a*b* coordinates and UV-visible spectroscopy revealed that the pigment was predominantly black.

Hydrodesulfurization of thiophene over coblat and molybdenum sulfides supported on MCM-41 materials

In this work was studied the potential application of molybdenum suphides supported on SiMCM-41 and A1MCM-41 materials in the thiophene hydrodesulfurization. The SiMCM-41 and AIMCM-41 materials were synthesized by hydrothermal method using cethyltrimethylammonium bromide as template. The deposition of the active HDS species was performed by solvent excess impregnation of ammonium tetrathiomolybdate salt over the supports followed by calcination. Cobalt was used as promoter in order to obtain a Co/(Co+Mo) atomic ratio of 0.3. The materials presented activity in thiophene HDS.

n-Heptane oxidation over co3o4-ceo2 catalyst

The present study reports the catalytic behavior of Co3O4-CeO2 in the oxidation of n-heptane. The results obtained showed that the catalyst give good activity in n-heptane oxidation with high selectivity to carbon dioxide.

Determination of the acidity of MCM-41 with different Si/Al ratios by the temperature programmed Desorption of Pyridine

Mesoporous catalysts of MCM-41 type with different Si/Al ratios were synthesized by the hydrothermal method and characterized by X-ray diffraction, nitrogen adsorption and thermogravimetric analysis. Their acidic properties were determined via the temperature programmed desorption of pyridine. Vyazovkin kinetic models were used to correlate the total acidity as a function of the Si/Al ratio with the apparent activation energy for pyridine desorption. The results obtained indicated that the catalysts possessed weak and medium acidic sites. An increase in the Si/Al ratio led to an increase in the activation energy for pyridine desorption.

SP4-5 Health check-up: changes occur in medical report

Introduction Many disorders of the skin, mucous membranes, throat, ears and nostrils can be detected simply by visual examination doctor. The telltale characteristics include size, shape, colour and location of the anomaly. Any change of function or appearance can lead to important consequences for physical and mental health. Objectives This research aims to identify the existence of medical and clinical changes related to various aspects, verifying the presence or absence of abnormalities, as well as the frequency of these. Methods This study was done with students of the school children Francisco Melo of the neighbourhood Moacir Andrade and with children of the neighbourhood Santa Lucia, both in Maceió-AL, all assisted by Extension Project Santa Lucia/Tabuleiro Novo (PESLUTAN). Results We analysed 88 children, of whom 45.5% were female. As for colour of skin and mucous membranes most were normal (86.4%), only 1.1% it was hipercor and 12.5% pale. Of the total, 21.6% were using some kind of medication, had no physical defect, 14.8% had an umbilical hernia, 30.7% had mycosis, 11.4% were observed warts, 6.8% had oropharyngeal hyperaemia and 5.7% had hypertrophic tonsils. Regarding changes in the nasal cavity, 7.9% had turbinate hypertrophy, hyperaemia were 5.7% and 5.7% had nasal secretions. And as for normal hearing, 5.7% had abnormal hearing, 2.3% had otitis and 1.1% with otalgia. Conclusion The results were quite impressive showing little change medical clinics, except only for fungal infections which accounted for 30%, showing a distance of information about the personal hygiene of children.

Síntese, caracterização e propriedades de sistemas contendo óxidos de lantânio, cério e níquel obtidos pelo método dos precursores poliméricos

The synthesis, characterization and photoluminescence property of the systems containing lanthanum, cerium and nickel oxides were studied. These materials were prepared by the polymeric precursors, calcined at temperatures ranging from 300 to 800 oC. Afterwards they were characterized by CHN analysis, thermogravimetric analysis, Fourier-transform infrared spectroscopy and X-ray diffraction. The results revealed the formation of the crystalline phases at 800 °C. The photoluminescence spectra of disordered systems have been observed at room temperature. The lanthanum, cerium and nickel system presented strong photoluminescence intensity centered at 599 nm when excited to 488 nm.

Propriedades espectroscópicas e parâmetros ópticos-eletrônicos dos complexos Ln(NO3)3.2DTPO.4H2O (Ln = Nd e Er)

Complexes with the composition Ln(NO3)3.2DTPO.4H2O (Ln = Nd and Er) were synthesized and characterized by infrared and visible absorption spectra (solid state and solution). The results of the absorption spectra in the solid state suggest that metal-ligand bonds are essentially electrostatic in all complexes. The absorption spectra of the nitrate salt solution presented smaller values of the oscillator strength when compared to the spectra of the complexes in the same solvent.

Avaliação dos parâmetros ópticos-eletrônicos do íon Nd3+nos compostos Nd(TMS)3.9H2O e Nd(TMS)(3)5BPMU.2H2O em solução

Electronic systems when submitted to an electrical field of electromagnetic radiation, acquire induced dipole moment, modifying the distribution of charge and distortion the molecular geometry. In this paper, electronic polarizability when evaluated for the Nd(TMS)3.9H2O and Nd(TMS)35BPMU.2H2O, were TMS = trifluorometanessulfonate and BPMU = bis(pentametileno)ureia, in methanol and acetonitrile solutions from the electronic absorption spectra. When the solvent is acetonitrile the distribution on electronic cloud showed greater values in the compounds.

Parâmetros cinéticos da degradação térmica de complexos entre percloratos de terras raras com lactama

Complexes of rare earth perchlorates with 2-azacyclononanone (AZA) were synthesized (molar ratio 1:8) by reaction of hydrated perchlorates in ethanol and triethlylorthoformate by a vapor diffusion method and they were characterized by complexometric analyses with EDTA, CHN microanalytical procedures, IR absorption spectra, thermogravimetry in air and N2 atmosphere and differential scanning calorimetry (DSC) in the N2 atmosphere. The theoretical kinetic study was carried out using the QBASIC program inputting the TG data.