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Zinc(II) phthalocyanines immobilized in mesoporous silica Al-MCM-41 and their a...

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 reflec...

New method for continuous monitoring of concrete E-modulus since casting

Photodegradation of atrazine and ametryn with visible light using water soluble...

Abstract The photodegradation of the herbicides atrazine and ametryn with visible light in aerated neutral aqueous solutions and 5, 10, 15, 20-tetrakis (2,6-dichloro-3-sulfophenyl) porphyrin or 5, 10, 15, 20-tetrakis (4-sulfophenyl) porphyrin as sensitizers are reported for the first time. Our findings show that the degradation percentage reached 30% for atrazine and 63% for ametryn. The final photoproducts we...

On the Low-Lying Excited States of sym-Triazine-Based Herbicides

We report a joint computational and luminescence study on the low-lying excited states of sym-triazines, namely, 1,3,5-triazine (1) and the ubiquitous herbicides atrazine [6-chloro-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine (2)] and ametryn [6-methylthio-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine (3)]. Geometrical structures, energetics, and transition and state properties of 1 and 2 were computed a...

A comparative study of water soluble 5,10,15,20-tetrakis(2,6-dichloro-3-sulfoph...

5,10,15,20-Tetrakis(2,6-dichloro-3-chlorosulfophenyl)porphyrin and its tin and zinc complexes were synthesized with high yields and fully characterized. The corresponding water-soluble 5,10,15,20-tetrakis(2,6-dichloro-3-sulfophenyl)porphyrins were obtained by hydrolysis with water. An extensive photophysical study of the new water soluble porphyrinic compounds was carried out including absorption and fluorescen...

On the Low-Lying Excited States of sym-Triazine-Based Herbicides

We report a joint computational and luminescence study on the low-lying excited states of sym-triazines, namely, 1,3,5-triazine (1) and the ubiquitous herbicides atrazine [6-chloro-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine (2)] and ametryn [6-methylthio-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine (3)]. Geometrical structures, energetics, and transition and state properties of 1 and 2 were computed a...

Kinetic and mechanistic aspects of the direct photodegradation of atrazine, atr...

Atrazine (1), Atraton (2) and Ametryn (3) are photodegraded upon 254 nm irradiation, yielding 2-OH-atrazine (4) as a photoproduct. Dealkylation products are also generated, and 4-ethylamino-6-isopropylamino-(1,3,5)-triazine was also found as a photoproduct of 3. The main photoreaction is proposed to be an addition-elimination, yielding 4, which subsequently photodegrades. The ease of photodegradation depends on...

Photooxidation of 4-chlorophenol sensitised by iron meso-tetrakis(2,6-dichloro-...

The photosensitised degradation of 4-chlorophenol (4-CP) by iron meso-tetrakis(2,6-dichloro-3-sulfophenyl)porphyrin (FeTDCPPS) has been studied in aerated aqueous solution, and is shown to lead to formation of p-benzoquinone (BQ) and p-hydroquinone (HQ) as main photoproducts. In deaerated solution no p-benzoquinone was formed. The photolysis products were identified by high performance liquid chromatography (HP...

Deactivation processes of the lowest excited state of [UO2(H2O)5]2+ in aqueous ...

A detailed analysis of the photophysical behaviour of uranyl ion in aqueous solutions at room temperature is given using literature data, together with results of new experimental and theoretical studies to see whether the decay mechanism of the lowest excited state involves physical deactivation by energy transfer or a chemical process through hydrogen atom abstraction. Comparison of the radiative lifetimes de...

Cation Association with Sodium Dodecyl Sulfate Micelles As Seen by Lanthanide L...

The interaction of trivalent lanthanides with sodium dodecyl sulfate micelles (SDS) in aqueous solution has been studied by a variety of experimental techniques. Potentiometric measurements with a sodium selective electrode, steady-state fluorescence spectra of Ce(III), emission lifetime measurements of Ce(III), Tb(III), and Eu(III), and electronic paramagnetic resonance spectra (EPR) of Gd(III) all show that t...