Mónica Silva

Zinc(II) phthalocyanines immobilized in mesoporous silica Al-MCM-41 and their applications in photocatalytic degradation of pesticides

In the present study the authors investigated a set of three new zinc(II) phthalocyanines (zinc(II) tetranitrophthalocyanine (ZnTNPc), zinc(II) tetra(phenyloxy)phthalocyanine (ZnTPhOPc) and the tetraiodide salt of zinc(II)tetra(N,N,N-trimethylaminoethyloxy) phthalocyaninate (ZnTTMAEOPcI)) immobilized into Al-MCM-41 prepared via ship-in-a-bottle methodology. The samples were fully characterized by diffuse reflectance-UV-vis spectroscopy (DRS-UV-vis), luminescence, thermogravimetric analysis (TG/DSC), N(2) adsorption techniques and elemental analysis. A comparative study was made on the photocatalytic performance upon irradiation within the wavelength range 320-460nm of these three systems in the degradation of pesticides fenamiphos and pentachlorophenol. ZnTNPc@Al-MCM-41 and ZnTTMAEOPcI@Al-MCM-41 were found to be the most active systems, with the best performance observed with the immobilized cationic phthalocyanine, ZnTTMAEOPcI@Al-MCM-41. This system showed high activity even after three photocatalytic cycles. LC-MS product characterization and mechanistic studies indicate that singlet oxygen ((1)O(2)), produced by excitation of these immobilized photosensitizers, is a key intermediate in the photocatalytic degradation of both pesticides.

Inorganic helping organic: recent advances in catalytic heterogeneous oxidations by immobilised tetrapyrrolic macrocycles in micro and mesoporous supports

This review considers several aspects (synthetic procedures and, particularly, catalytic applications) of the recent literature (since 2000) regarding the immobilisation of tetrapyrrolic macrocycles (namely porphyrins and phthalocyanines) in micro (NaY and NaX zeolites) and mesoporous inorganic supports (M41S family), and their employment in catalysis, predominantly in oxidation. Emphasis is placed on photocatalysis, which is of importance in the degradation of pesticides, herbicides, health care, personal care and domestic care products, all of which represent a current major environmental concern. Pertinent reflections are presented on the nature of both synthetic issues and catalytic evaluations, within the perspective of what has happened in the field so far, and what are the main guidelines and problems for future developments.

Immobilization of 5,10,15,20-tetrakis-(2-fluorophenyl)porphyrin into MCM-41 and NaY: Routes toward photodegradation of pesticides

NaY zeolite and MCM-41 mesoporous molecular sieve were used as supports for immobilization of 5,10,15,20-tetrakis-(2-fluorophenyl)porphyrin (TFPP) using adsorption and ship-in-the-bottle routes involving the nitrobenzene method. The materials obtained were characterized by thermogravimetry/differential thermal analysis (TG/DTA), nitrogen adsorption, UV–vis absorption, diffuse reflectance (DRS), and luminescence spectroscopy. Although the porphyrin could easily be synthesized inside MCM-41 pores using the ship-in-the-bottle route, no significant porphyrin was formed in the smaller supercages of NaY zeolite, since the reaction stops at the dipyrrolylmethene intermediate (FDPM). Promising preliminary studies were made in the photodegradation of the pesticides, 2,3,5-trimethylphenol (TMP) and mecoprop (MCPP), using as catalyst TFPP encapsulated in mesoporous MCM-41 material. The 2-hydroxy-methyl-hydroquinone and 4-chloro-2-methylphenol were identified as the main degradation products of MCPP. The encapsulated system resulting from the TFPP template synthesis shows significantly enhanced performance when compared with adsorbed porphyrin in both supports.

A robótica no apoio a inclusão de alunos com NEE

O estudo apresenta as percecoes dos docentes do ensino regular (DER) e de educacao especial (DEE) face ao uso de robos em salas de aula por criancas com limitacoes na manipulacao e comunicacao, no âmbito do projeto Using Assistive Robots to Promote Inclusive Education (UARPIE). Foram desenvolvidos dois sistemas roboticos: um fisico e outro virtual, cujos comandos foram integrados no sistema de comunicacao utilizados pelas criancas participantes no estudo. Os sistemas usados permitiram as criancas a manipulacao de objetos de aprendizagem e a comunicacao enquanto realizavam atividades de portugues, matematica e estudo do meio. Cada crianca participou em tres sessoes orientadas pelos respetivos docentes. A recolha de dados implicou, entre outros, a realizacao de entrevistas iniciais e finais aos docentes. Os docentes consideraram positivo o uso deste recurso, mas nao se sentiam totalmente preparados para o utilizarem sem apoio externo.

USING ASSISTIVE ROBOTS TO PROMOTE INCLUSIVE EDUCATION – FIRST USER TRIALS

This paper describes the first user trials results of an integrated augmented manipulation and communication robotic assistive technology to enable children with disabilities to actively participate, along with their typically developing peers, in academic activities requiring the manipulation of educational items. Five children with different degrees of physical and communication impairments used the system in their pre-school or first grade classes to perform academic activities designed together with their teachers. Goal attainment scales were defined for each child to assess their performance in the areas of communication, participation, autonomy, and academic achievement. Teachers were interviewed to evaluate their perceptions of the use of the assistive technology and its impact on the student and in the classroom. In general, goal attainment scaling results show that the outcomes were the expected or better for all academic goals. Progress was more moderate for communication, participation, and autonomy goals. Teachers opinions about the system and its impact were positive, though they pointed the need for technical support to prepare and conduct the adapted activities.