Publications by authors named "Claudia T Arranja"

Purely organic chiral molecular assemblies in the solid state hold great potential for non-linear optical applications. Herein, a newly synthesised molecular system is reported, namely, dicinnamalacetone, an otherwise planar molecule that crystallises in a disordered non-centrosymmetric form with four different conformations having an overall predominance of a particular helicity. A combined experimental and theoretical approach, including single-crystal X-ray diffraction, Kurtz-Perry and ab initio methods, is employed to characterise the system and benchmark the performance of hybrid functionals for the prediction of non-linear optical properties and electronic excitations.

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Fluorescent materials are important for low-cost opto-electronic and biomedical sensor devices. In this study we present the synthesis and characterization of graphene modified with bis-thiosemicarbazone (BTS). This new material was characterized using Fourier transform infrared spectroscopy (FT-IR), Ultraviolet-visible (UV-Vis) and Raman spectroscopy techniques.

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In this paper, for the first time, chemically modified 5,10,15,20-meso-tetra-(para-amino)-phenyl-porphyrin/TiO (TPAPP/TiO) was prepared and used for the degradation of an azo dye Acid Black 1 (AB 1) under direct sunlight. Initially, TiO was prepared by sol-gel method. Before making a TPAPP/TiO composite, the surface modification of TiO was carried out with glycidoxypropyltrimethoxy silane (GPTMS) which acts as a coupling agent.

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Photodynamic therapy (PDT) is a selective and minimally invasive therapeutic approach, involving the combination of a light-sensitive compound, called a photosensitizer (PS), visible light and molecular oxygen. The interaction of these per se harmless agents results in the production of reactive species. This triggers a series of cellular events that culminate in the selective destruction of cancer cells, inside which the photosensitizer preferentially accumulates.

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A new 5,10,15,20-tetra-(phenoxy-3-carbonyl-1-amino-naphthyl)-porphyrin was prepared by an isocyanate condensation reaction and its photophysical properties fully evaluated, both in terms of photostability and singlet oxygen production. It shows considerably enhanced photostability when compared with the parent 5,10,15,20-tetra-(3-hydroxy-phenyl)-porphyrin, with the photodegradation quantum yields for T(NAF)PP and T(OH)PP being 4.65×10(-4) and 5.

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In the title compound, C(9)H(13)NO(2), there are two independent mol-ecules per asymmetric unit. The mol-ecules are very similar and almost planar, with the ethoxy-carbonyl group anti to the pyrrole N atom. The two independent mol-ecules are joined into dimeric units by strong hydrogen bonds between NH groups and carbonyl O atoms.

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