Journal of Photochemistry and Photobiology A: Chemistry, 2013
ABSTRACT a b s t r a c t The photocatalytic efficiency of different TiO 2 powders, prepared by a ... more ABSTRACT a b s t r a c t The photocatalytic efficiency of different TiO 2 powders, prepared by a sol–gel method and annealed at different temperatures, has been evaluated through the TiO 2 photosensitized degradation (until mineralization) of acetone, as model reaction, in a static gas phase reactor. Two profiles "TiO 2 effi-ciency vs. powders annealing temperature" have been obtained analyzing the produced CO 2 by gas-chromatography or by an IR gas sensor. Despite the different operative conditions, that are: (i) acetone initial concentration (2400 or 600 ppm), (ii) relative humidity (40 or 70%) and (iii) reaction time (a test after 7 h or a continuous monitoring until 1 h), the two profiles are similar and show the same TiO 2 effi-ciency maximum (at 700 • C calcination temperature of the powder). The efficiency increase until 700 • C could depend on the crystallinity increase of anatase form and on the decreasing amount of physisorbed water at the surface of the semiconductor. The efficiency decrease observed at higher temperatures could be ascribed to the gradual transformation of anatase into rutile form, less reactive. Differently, parame-ters as specific surface and mesopore volume of TiO 2 powders seem to be less important for the powder efficiency.
ABSTRACT Desulfurization represents a crucial step in fuel processing for high temperature fuel c... more ABSTRACT Desulfurization represents a crucial step in fuel processing for high temperature fuel cells, because of catalysts stringent requirements. Moreover, when fuel cell stacks are used in micro-CHP applications, it is necessary to build an efficient and compact system. The use of biogas from anaerobic digestion could have a significant impact in terms of fossil fuels saving and environmental conservation. Biogas contains different impurities, among which H2S represents one of the most harmful components.
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Mesoporous composites made of silica and α-zirconium phosphate (SiO2·xZrP) were synthesized start... more Mesoporous composites made of silica and α-zirconium phosphate (SiO2·xZrP) were synthesized starting from mixtures of delaminated ZrP dispersions and tetrapropylammonium oligosilicate solutions. The surface area of the composites reaches a maximum of 700 m2/g for x≈0.02, while the average pore diameter is about 40 Å for x in the range 0.05–0.35. In order to increase proton conductivity at low relative
... Valeria Ambrogi a , Corresponding Author Contact Information , E-mail The Corresponding Autho... more ... Valeria Ambrogi a , Corresponding Author Contact Information , E-mail The Corresponding Author , Luana Perioli a , Cinzia Pagano a , Loredana Latterini c , Fabio Marmottini b , Maurizio Ricci a ... c Dipartimento di Ingegneria Civile ed Ambientale, Via G. Duranti 93, Perugia, Italy. ...
ABSTRACT A good exfoliation of layered γ-zirconium phosphate in aqueous medium at room temperatur... more ABSTRACT A good exfoliation of layered γ-zirconium phosphate in aqueous medium at room temperature has been obtained by intercalation of short alkylamines such as methyl-, dimethyl- and ethyl-amine. No appreciable exfoliation was observed when butylamine or longer alkylamines were intercalated, while intermediate behavior was obtained with the intercalation of propylamine. Since a good exfoliation of this layered compound is an essential step for its functionalization by topochemical reactions with phosphonic or phosphinic acids, the amine intercalation compounds and the various steps of the intercalation processes were investigated in order to obtain information on the mechanism of the exfoliation and a model of this mechanism is proposed. The use of the colloidal dispersion of exfoliated lamellae for the preparation of auto-consistent and flexible membranes as well as thin supported films of γ-zirconium phosphate is described.
Porous zirconium phosphate (P-ZrP) and zirconium benzenephosphonate (P-ZrBP) were prepared in the... more Porous zirconium phosphate (P-ZrP) and zirconium benzenephosphonate (P-ZrBP) were prepared in the presence of an anionic surfactant acting as a template. Poorly crystalline materials with a P/Zr molar ratio equal to 2 and having a relatively high surface area and micro/mesoporosity have been obtained. The interaction of myoglobin with the two types of surfaces, the hydrophobic P-ZrBP and the hydrophilic P-ZrP, was investigated, and the adsorption isotherms were determined at different pH and temperature values. A model was proposed for the mechanism of the interaction of the protein with the surface based on the shape of the adsorption isotherm and the physical-chemical properties of myoglobin. The pH has been found to be an important parameter for determining the maximum adsorption capacity of P-ZrBP and P-ZrP for myoglobin molecules because of the changes that occur in the type and net charge of the protein surface as the pH of the medium changes. Protein binding affinity and capacity increase when the temperature is increased. This phenomenon occurs because myoglobin varies its conformation at high temperature with an increase in the exposed hydrophobic region. This process causes a stronger hydrophobic interaction between the protein and the adsorbent and reduces the repulsion between the adsorbed molecules. Studies on the activities of the obtained biocomposites are in progress.
Abstract An aluminophosphate with a layer structure has been synthesized hydrothermally. The rati... more Abstract An aluminophosphate with a layer structure has been synthesized hydrothermally. The ratio P/Al= 2 for the framework; its structure consists of Al-centered tetrahedra and P-centered tetrahedra as basic building units to form a two-dimensional layer structure. The ...
Journal of Inclusion Phenomena and Molecular Recognition in Chemistry, 1989
Many primary diamines H2N(CH2)nNH2 (all the members withn ranging from 0 to 12 with the exception... more Many primary diamines H2N(CH2)nNH2 (all the members withn ranging from 0 to 12 with the exception ofn =I 1) have been intercalated within the phosphate regions of layered zirconium phosphate-phosphite. As a general rule, intercalation occurs in two steps that are not well differentiated. The first one leads to intercalation compounds in which the diamines are arranged with their alkyl
Journal of Photochemistry and Photobiology A: Chemistry, 2013
ABSTRACT a b s t r a c t The photocatalytic efficiency of different TiO 2 powders, prepared by a ... more ABSTRACT a b s t r a c t The photocatalytic efficiency of different TiO 2 powders, prepared by a sol–gel method and annealed at different temperatures, has been evaluated through the TiO 2 photosensitized degradation (until mineralization) of acetone, as model reaction, in a static gas phase reactor. Two profiles "TiO 2 effi-ciency vs. powders annealing temperature" have been obtained analyzing the produced CO 2 by gas-chromatography or by an IR gas sensor. Despite the different operative conditions, that are: (i) acetone initial concentration (2400 or 600 ppm), (ii) relative humidity (40 or 70%) and (iii) reaction time (a test after 7 h or a continuous monitoring until 1 h), the two profiles are similar and show the same TiO 2 effi-ciency maximum (at 700 • C calcination temperature of the powder). The efficiency increase until 700 • C could depend on the crystallinity increase of anatase form and on the decreasing amount of physisorbed water at the surface of the semiconductor. The efficiency decrease observed at higher temperatures could be ascribed to the gradual transformation of anatase into rutile form, less reactive. Differently, parame-ters as specific surface and mesopore volume of TiO 2 powders seem to be less important for the powder efficiency.
ABSTRACT Desulfurization represents a crucial step in fuel processing for high temperature fuel c... more ABSTRACT Desulfurization represents a crucial step in fuel processing for high temperature fuel cells, because of catalysts stringent requirements. Moreover, when fuel cell stacks are used in micro-CHP applications, it is necessary to build an efficient and compact system. The use of biogas from anaerobic digestion could have a significant impact in terms of fossil fuels saving and environmental conservation. Biogas contains different impurities, among which H2S represents one of the most harmful components.
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Mesoporous composites made of silica and α-zirconium phosphate (SiO2·xZrP) were synthesized start... more Mesoporous composites made of silica and α-zirconium phosphate (SiO2·xZrP) were synthesized starting from mixtures of delaminated ZrP dispersions and tetrapropylammonium oligosilicate solutions. The surface area of the composites reaches a maximum of 700 m2/g for x≈0.02, while the average pore diameter is about 40 Å for x in the range 0.05–0.35. In order to increase proton conductivity at low relative
... Valeria Ambrogi a , Corresponding Author Contact Information , E-mail The Corresponding Autho... more ... Valeria Ambrogi a , Corresponding Author Contact Information , E-mail The Corresponding Author , Luana Perioli a , Cinzia Pagano a , Loredana Latterini c , Fabio Marmottini b , Maurizio Ricci a ... c Dipartimento di Ingegneria Civile ed Ambientale, Via G. Duranti 93, Perugia, Italy. ...
ABSTRACT A good exfoliation of layered γ-zirconium phosphate in aqueous medium at room temperatur... more ABSTRACT A good exfoliation of layered γ-zirconium phosphate in aqueous medium at room temperature has been obtained by intercalation of short alkylamines such as methyl-, dimethyl- and ethyl-amine. No appreciable exfoliation was observed when butylamine or longer alkylamines were intercalated, while intermediate behavior was obtained with the intercalation of propylamine. Since a good exfoliation of this layered compound is an essential step for its functionalization by topochemical reactions with phosphonic or phosphinic acids, the amine intercalation compounds and the various steps of the intercalation processes were investigated in order to obtain information on the mechanism of the exfoliation and a model of this mechanism is proposed. The use of the colloidal dispersion of exfoliated lamellae for the preparation of auto-consistent and flexible membranes as well as thin supported films of γ-zirconium phosphate is described.
Porous zirconium phosphate (P-ZrP) and zirconium benzenephosphonate (P-ZrBP) were prepared in the... more Porous zirconium phosphate (P-ZrP) and zirconium benzenephosphonate (P-ZrBP) were prepared in the presence of an anionic surfactant acting as a template. Poorly crystalline materials with a P/Zr molar ratio equal to 2 and having a relatively high surface area and micro/mesoporosity have been obtained. The interaction of myoglobin with the two types of surfaces, the hydrophobic P-ZrBP and the hydrophilic P-ZrP, was investigated, and the adsorption isotherms were determined at different pH and temperature values. A model was proposed for the mechanism of the interaction of the protein with the surface based on the shape of the adsorption isotherm and the physical-chemical properties of myoglobin. The pH has been found to be an important parameter for determining the maximum adsorption capacity of P-ZrBP and P-ZrP for myoglobin molecules because of the changes that occur in the type and net charge of the protein surface as the pH of the medium changes. Protein binding affinity and capacity increase when the temperature is increased. This phenomenon occurs because myoglobin varies its conformation at high temperature with an increase in the exposed hydrophobic region. This process causes a stronger hydrophobic interaction between the protein and the adsorbent and reduces the repulsion between the adsorbed molecules. Studies on the activities of the obtained biocomposites are in progress.
Abstract An aluminophosphate with a layer structure has been synthesized hydrothermally. The rati... more Abstract An aluminophosphate with a layer structure has been synthesized hydrothermally. The ratio P/Al= 2 for the framework; its structure consists of Al-centered tetrahedra and P-centered tetrahedra as basic building units to form a two-dimensional layer structure. The ...
Journal of Inclusion Phenomena and Molecular Recognition in Chemistry, 1989
Many primary diamines H2N(CH2)nNH2 (all the members withn ranging from 0 to 12 with the exception... more Many primary diamines H2N(CH2)nNH2 (all the members withn ranging from 0 to 12 with the exception ofn =I 1) have been intercalated within the phosphate regions of layered zirconium phosphate-phosphite. As a general rule, intercalation occurs in two steps that are not well differentiated. The first one leads to intercalation compounds in which the diamines are arranged with their alkyl
Uploads
Papers by Fabio Marmottini