In this paper, industrial dyes, Disperse Red and Disperse Orange, were studied as model pollutants to show the excellent performance of olive pomace (OP) in sequestering and recovering these dangerous dyes from wastewater. The nature of interactions involved between dyes and OP were inferred by changing several parameters: contact time, pomace dosage, pH and temperature values. Visible spectroscopy was mainly used to obtain the percentage of the removed dyes, while SEM (scanning electron microscopy), FTIR-ATR (Fourier transform infra-red spectroscopy in total attenuated reflectance), TG (thermo gravimetric) and XPS (X-ray photoelectron spectroscopy) analyses were used to carefully investigate the systems. The recovery of dyes was also obtained using glacial acetic acid, the auxiliary solvent used during the dyeing processes, enabling the recycling of both of the adsorbent material and dyes presenting a green and a wide-ranging strategic approach.

The removal of Disperse Blue 73 from aqueous solutions, using olive pomace as adsorbent material, was investigated in a batch system with respect to contact time, pomace dosage, pH and temperature. SEM, FTIR-ATR, TG and XPS analyses appeared as powerful tools to characterize olive pomace, before and after the adsorption of dye, while UV–Visible analyses were used to quantify the amount of loaded dye on adsorbent material. The pseudo-second order kinetic model well fitted the experimental data and described the kinetic adsorption process. The dye desorption in glacial acetic acid was also obtained with the dye recovery enabling the recycle both of adsorbent material and dye itself. Five consecutive cycles of adsorption and desorption were performed and the absence of any degradation process affecting the dye after the adsorption/desorption cycles was observed. The recorded absorption spectrum, in acetic acid solution, before and after the desorption, confirmed such result. An environmentally friendly and a low cost material is thus presented, showing the excellent olive pomace potential both in disperse blue adsorption (with an efficiency of 100%) and desorption (with a mean value of 80% for each cycle). Additionally, an alternative environmental friendly use of olive oil solid residues is presented.

In recent years the development of chitosan (CH) based materials as useful adsorbent polymeric matrices is an expanding field in the area of adsorption science. Even though CH has been successfully used for dye removal from aqueous solutions due to its low cost, no considerations have been made about, for example, the effect of changing the pH of chitosan hydrogelor about the dehydrating effect of Ethanol (EtOH) treatment of chitosan film on the dyes removal from water. Consequently in our laboratory we carried out a study focusing the attention, mainly, on the potential use of CH films under different conditions, such as reducing the intrinsic pH, increasing the hydrophobic character by means of ethanol treatment and neutralization of CH films to improve their absorption power. Textile anionic dyes named Direct Red 83:1, Direct Yellow 86 and Direct Blue 78 have been studied with the aim of reducing the contact time of CH film in waste water improving the bleaching efficiency. Neutralized acid CH film and longtime dehydrated one result to be the better films in dye removal from water. Also the reduction of the CH solution acidity during the film preparation determines the decreasing of the contact time improving the results. The effect of initial dye concentration has been examined and the amount of dye adsorption in function of time t, qt (mg/cm2), for each analyzed film has been evaluated comparing the long term effect with the decoloration rate. A linear form of pseudo-first-order Lagergren model has been used and described. The best condition for removing all examined dyes from various dye solutions appears to be the dehydration of a novel projected CH film obtained by means of the film immersion in EtOH for 4 days. Also CH films prepared by well-known literature procedure and neutralized with NaOH treatment appear having an excellent behavior, however the film treatment requires a large quantity of water and time.

The goal of this study is the chemical-physical characterization of a drug delivery system for Photodynamic Therapy (PDT) [1]: Chlorophyll a (Chl a) entrapped in a water-soluble matrix made of Ca2+ cross-linked alginic acid [2]. Chl a, a lipophilic natural pigments, is a molecule with characteristic photosensitising properties usable in PDT. In PDT the photosensitizer, selectively accumulated in malignant tissues, produces, upon light irradiation, reactive oxygen species (ROS) which are responsible for cytotoxicity of neoplastic cells and tumor regression since induce cellular damage via apoptosis, necrosis, or both. The Chl a/alginate microspheres produced were characterized by means of different techniques as UV-Vis absorption and emission spectroscopy, FT-IR spectroscopy, Atomic Force Microscopy, Dynamic Light Scattering and Differential Scanning Calorimetry. Moreover, it was estimated the ROS production, mainly singlet oxygen (1O2) by means of a selective luminescent probe, Singlet Oxygen Sensor Green [3] and in vitro tests were carried out on human adenocarcinoma cells (HT29). [1] R.M. Szeimies, S. Karrer, S. Radakovic-Fijan. J. Am. Acad. Dermatol., 2002, 47, 259-262. [2] G.T. Grant, E.R. Morris, D.A. Rees, P.J.C. Smith, D. Thom. FEBS letters, 1973, 32,195-198. [3] A. Gollmer, J. Arnbjerg, H. Frances, F.H. Blaikie, B.Wett Pedersen, T. Breitenbach, K. Daasbjerg, P.R. Ogilby. Photochemistry and Photobiology, 2011, 87, 671–679.

Heterostructures formed of films of organic-capped ZnO and TiO2 nanocrystals (both with the size of ca. 6 nm) and photosynthetic pigments were prepared and characterized. The surface of optically transparent electrodes (Indium Tin Oxide) was modified with nanocrystals and prepared by colloidal synthetic routes. The nanostructured electrodes were sensitized by a mixture of chlorophyll a and carotenoids. The characterization of the hybrid structures, carried out by means of steady-state optical measurements, demonstrated such class of dyes able to extend the photoresponse of the large band-gap semiconductors. The charge-transfer processes between the components of the heterojunction were investigated, and photoelectrochemical measurements taken on the sensitized ZnO and TiO2 nanocrystals electrodes elucidated the photoactivity of the heterojunctions as a function of the dyes and of the red-ox mediator used in solution. The effect of methyl viologen as different red-ox mediator was also evaluated in order to show its effect on the heterojunction photoactivity. The overall results contributed to describe the photoelectrochemical potential of the investigated heterojunctions, highlighting a higher response of the dye-sensitized ZnO nanocrystals, and then provided the TiO2-modified counterparts.

Nanocomposite solutions formed of Poly [(9,9-diesilfluorene)-(2,7 diyl)-alt-(2,5-dimetil-1,4-phenilene)] and highly luminescent nanocrystals of CdSe coated with a shell of ZnS (CdSe@ZnS) with different size have been obtained by using a common solvent and characterized by means of absorption and emission spectroscopy. Viscosity has been investigated, in order to prove the suitability of the inks for the printing processing. The homogeneous nanocomposites have been precisely dispensed by ink-jet printing, using drop-on-demand mode onto glass substrates. The deposited micro-scale pixels have been morphologically characterized by means of fluorescence microscopy, 3D profilometry and Atomic Force Microscopy (AFM). The results demonstrate that the spectroscopical properties of the components have been effectively conveyed to the final nanocomposites, retaining the size dependent feature of the inorganic moiety, and providing a suitable ink with for fabricating reproducible microstructures.

tThe aim of this work is to study the nature of reactive oxygen species, ROS, arisen from Chitosan/2-HP--Cyclodextrin/Chlorophyll a (CH/CD/Chla) blended biofilm under a photodynamic activity. Suitablemolecules, called primary acceptors, able to react selectively with ROS, in turn generated by the pho-tosensitizer (PS), herein Chla, are used to attempt this purpose. The changes of the absorption and theemission spectra of these acceptors after the irradiation of aqueous solution containing the active biofilmhave provided the specific nature of ROS and thus the main pathway of reaction followed by PS, in ourcondition. The1O2formation was unveiled using Uric Acid (UA) and 9,10-diphenilanthracene (DPA). Onthe other hand, 2,7- dichlorofluorescin and Ferricytochrome c (Cyt-c) were used to detect the formationof hydrogen peroxide and superoxide radical anion, respectively. Results suggest that among the possiblepathways of reaction, namely Type I and Type II, potentially followed by PSs, in our condition the hybridbiofilm CH/CD/Chla follows mainly Type II mechanism with the formation of1O2. However, the latter isinvolved in subsequent pathway of reaction involving Chla inducing, in addition, the formation of O2•−and H2O2.

Nanostructured films based on Au nanorods (NRs) have been obtained by layer-by-layer (LbL) assembly driven by electrostatic interaction between metal nanoparticles and polyelectrolytes. Multilayer films have been fabricated by using LbL assembly of poly(sodium styrenesulfonate) (PSS) and positively charged Au NRs on a polyelectrolyte-modified substrate. The effect of fabrication parameters, including the nature of the substrate, the polyelectrolyte initial anchoring layer, and the number of layers has been investigated by means of UV vis absorbance spectroscopy and atomic force microscopy (AFM). The results demonstrated the dependence of morphology and plasmonic features in the multilayered nanostructured architectures from the nature of the anchoring polyelectrolyte on the substrate, the number of layers, and the kind of NR mutual assembly. In addition, a study of the electrochemical activity at the solid/liquid interface has been carried out in order to assess charge transport through the NR multilayer by using two molecular probes in solution, namely, potassium ferricyanide, a common and well-established redox mediator with reversible behavior, and cytochrome C, a robust model redox protein. The presented systematic study of the immobilization of Au NRs opens the venue to several application areas, such as (bio)chemical sensing.

A low band-gap copolymer PDTBTFV alternating bis-thienyl-(bis-alkoxy)-benzothiadiazole blocks with difluorovinylene units and its non-fluorinated counterpart PDTBTV have been synthesized and characterized as donor materials in bulk heterojunction (BHJ) solar cells with PCBM as the acceptor. The solar cells with the fluorinated polymer show better photovoltaic performances than those recorded with the non-fluorinated material. Comparative spectroscopic and computational studies, together with morphological, electrical and optical characterization of thin films, have been carried out to shed light on the reasons for the improvement of performances as induced by the double bond fluorination. Our study introduces the fluorinated double bond as a new conjugated unit in donor polymers for BHJ solar cells.

The stability of Chlorophyll a in water during prolonged exposure, at room temperature, to a neon lamp has been investigated by means of UV–vis and fluorescence spectroscopies. In addition, the Chlorophyll a (photo)stability evaluation in presence of suitable carriers has been performed in order to investigate its reactivity under the same conditions, for possible and future applications in Antimicrobial Photodynamic Therapy. Cetyltrimethylammonium chloride was chosen to solubilize Chlorophyll a in water. While, cetyltrimethylammonium chloride-capped gold nanoparticles offer a great opportunity because combine the Chlorophyll a action, used as a photosensitizer in Antimicrobial Photodynamic Therapy, with gold nanoparticles effect used in photothermal therapy. Indeed, the latter ones have exhibited an interesting rise of temperature if irradiated with visible light. Overall, both examined systems, cetyltrimethylammonium chloride/Chlorophyll a and gold nanoparticles/Chlorophyll a, were able to induce the Reactive Oxygen Species formation fundamental for a potential application in Antimicrobial Photodynamic Therapy.

Photodynamic therapy (PDT) is a way of treating malignant tumors and hyperproliferative diseases. It is based on the use of photosensitizer, herein the chlorophyll a (chl a), and a light of an appropriate wavelength. The interaction of the photosensitizer (PS) with the light produces reactive oxygen species (ROS), powerful oxidizing agents, which cause critical damage to the tissue. To solubilize chl a in aqueous solution and to obtain it as monomer, we have used cyclodextrins, carriers which are able to interact with the pigment and form the inclusion complex. The aim of this study is to examine which types of ROS are formed by Chl a/cyclodextrin complexes in phosphate buffered solution and cell culture medium, using specific molecules, called primary acceptors, which react selectively with the reactive species. In fact the changes of the absorption and the emission spectra of these molecules after the illumination of the PS provide information on the specific ROS formation. The 1O2 formation has been tested using chemical methods based on the use of Uric Acid (UA), 9,10-diphenilanthracene (DPA) and Singlet oxygen sensor green (SOSG) and by direct detection of Singlet Oxygen (1O2) luminescence decay at 1270nm. Moreover, 2,7-dichlorofluorescin and ferricytochrome c (Cyt Fe3+) have been used to detect the formation of hydrogen peroxide and superoxide radical anion, which reduces Fe3+ of the ferricytochrome to Fe2+, respectively.

Since several years the inclusion of organic compounds (guests) within the hydrophobic cavity (host) of cyclodextrins (CDs) has been the subject of many investigations. Interestingly, the formation of inclusion complexes could affect the properties of the guest molecules and, for example, the influence of the delivery system can be a method to improve/change the photochemical behavior of the guest. In particular, very recent studies have shown the protective role of CDs preventing the degradation of the encapsulated guest. Starting from this consideration, in this work, only the structure and complexation mode of the inclusion complexes involving 4-thiothymidine (S4TdR, a known photosensitizer) and five CDs, namely 2-hydroxypropyl-α-cyclodextrin (2-HP-α-CD), 2-hydroxypropyl-β-cyclodextrin (2-HP-β-CD), 2-hydroxypropyl-γ-cyclodextrin (2-HP-γ-CD), heptakis-(2,6-di-O-methyl)-β-cyclodextrin (DIMEB CD) and heptakis-(2,3,6-tri-O-methyl)-β-cyclodextrin (TRIMEB CD) were investigated by different spectroscopic techniques (UV–vis, FTIR–ATR, 1H NMR) and cyclic voltammetry analysis (CV). This work is necessary for a prospective research on the photoreactivity of S4TdR in aqueous environment and in the presence of CDs to prevent its degradation under irradiation. UV–vis, FTIR–ATR and CV measurements suggested the formation of supramolecular structures involving the employed CDs and mainly the pyrimidine ring of S4TdR. 1H NMR analyses confirmed such indication, unveiling the presence of inclusion complexes. The strongest and deepest interactions were suggested when TRIMEB and DIMEB CDs were studied. The S4TdR affinity towards CDs was also evaluated by using the Benesi–Hildebrand (B–H) equation at 25 °C employing CV and 1H NMR methods. The stoichiometry of the interaction was also inferred and it appears to be 1:1 for all examined CDs.

Atmospheric pressure(AP)DielectricBarrierDischarges(DBD)generatedinairwereperformedonwater, Phosphate BufferSaline(PBS)andDulbecco'sModified Eagle'sMedium(DMEM)inordertoevaluate their potentialtogeneratehydrogenperoxide(H2O2), nitrite(NO2 − ) andnitrate(NO3 − ) species.Differences in cellgrowthandmorphologywerefoundintwodifferenttypesofeukaryoticcells,immortalandstem cells, incubatedfor1hinplasmatreatedDMEM,revealingaselectivityofthetreatment.

The life cycle of the bacterium Rhodobacter sphaeroides was investigated by isothermal microcalorimetry using two different procedures based on the use of a static ampoule and a flow cell, respectively. In the static ampoule method it is possible to follow the growth phase and also the death phase which cannot be revealed by total biomass based techniques like turbidimetry. However, different cellular metabolisms, possibly due do the oxygen limitation occurring during the bacterial life cycle, produce complex behavior in the experimental curves. In the stop-flow cell mode this limitation is overcome as the bacteria are grown outside the calorimeter under well-defined aerobic conditions and aliquots of cell suspension are transferred in the calorimeter at different time intervals. The complex behavior shown in the static ampoule mode was successfully analyzed by a population evolution model based on a Fujikawa modified logistic equation which provides a quantitative description of the process.

In this work nanocomposites based on organic-capped semiconductor nanocrystals formed of a core of CdSe coated with a shell of ZnS (CdSe@ZnS), with different sizes, and a semiconducting conjugated polymer, namely poly[(9,9-dihexylfluoren-2,7-diyl)-alt- (2,5-dimethyl-1,4-phenylene)] (PF-DMB) have been investigated. The nanocomposites are prepared by mixing the pre-synthesized components in organic solvents, thereby assisting the dispersion of the organic-coated nano-objects in the polymer host. UV–vis steady state and time-resolved spectroscopy along with (photo)electrochemical techniques have been performed to characterize the obtained materials. The study shows that the embedded nanocrystals increase the PF-DMB stability against oxidation and, at the same time, extend the light harvesting capability to the visible spectral region, thus resulting in detectable photocurrent signals. The nanocomposites have been dispensed by means of a piezo-actuated inkjet system. Such inks present viscosity and surface tension properties well suited for stable and reliable drop-on-demand printing using an inkjet printer. The fabrication of arrays of single-color pixels made of the nanocomposites and micrometers in size has been performed. Confocal and atomic force microscopy have confirmed that inkjet-printed microstructures present the intrinsic emission properties of both the embedded nanocrystals and PF-DMB, resulting in a combined luminescence. Finally, the morphology of the printed pixels is influenced by the embedded nanofillers.

In this work nanocomposites based on organic-capped semiconductor nanocrystals formed of a core of CdSe coated with a shell of ZnS (CdSe@ZnS), with different sizes, and a semiconducting conjugated polymer, namely poly[(9,9-dihexylfluoren-2,7-diyl)-alt-(2,5-dimethyl-1,4-phenylene)] (PF-DMB) have been investigated. The nanocomposites are prepared by mixing the pre-synthesized components in organic solvents, thereby assisting the dispersion of the organic-coated nano-objects in the polymer host. UV-vis steady state and time-resolved spectroscopy along with (photo) electrochemical techniques have been performed to characterize the obtained materials. The study shows that the embedded nanocrystals increase the PF-DMB stability against oxidation and, at the same time, extend the light harvesting capability to the visible spectral region, thus resulting in detectable photocurrent signals. The nanocomposites have been dispensed by means of a piezo-actuated inkjet system. Such inks present viscosity and surface tension properties well suited for stable and reliable drop-on-demand printing using an inkjet printer. The fabrication of arrays of single-color pixels made of the nanocomposites and micrometers in size has been performed. Confocal and atomic force microscopy have confirmed that inkjet-printed microstructures present the intrinsic emission properties of both the embedded nanocrystals and PF-DMB, resulting in a combined luminescence. Finally, the morphology of the printed pixels is influenced by the embedded nanofillers.

In this work the ability of “bleached” oil mill solid waste to reduce the dyestuff content in industrial textile wastewater was studied. Bleaching treatment consists in a preliminary oil mill solid waste management with NaOH and NaClO2 for obtaining cellulosic materials, mainly removing lignin from the waste surface. Thus, a novel bioadsorbent from agricultural residues, named bleached olive pomace (OP), was presented. Direct Blue 78 was studied as a model azoic dye. Experiments were planned to study the effect of different initial conditions on the adsorption processes: oil mill waste amount as grains and as a fine powder (OPP), solution temperature values, initial dye concentration, pH values and electrolytes influence. The results showed that the adsorption process using bleached oil mill waste determined an excellent degree of water color reduction, reaching the best work conditions when pH 2 and OPP were used. The presence of electrostatic interactions was also suggested. The adsorption appeared to be influenced by temperature values showing an endothermic character. Interestingly, to confirm the role of ionic interactions between dye and sorbent at pH 2, fashionable results were obtained. The adsorption process was verified also at pH 6 with 100% of dye removal in presence of both NaCl and Na2SO4 avoiding the aforementioned strong acid conditions. A very important aspect of this work is the recycle of both the dye and the adsorbent, with particular attention to the dye reuse for coloring cotton fabric.

This paper reports a study on the photoelectrochemical processes occurring at the interface of ZnO nanocrystals/MEH-PPV composites. Colloidal chemical routes were used to obtain size controlled non-hydrolytic ZnO nanocrystals (NCs) dispersible in organic solvents, while a low molecular weight poly[2-methoxy-5-(2'-ethylhexyloxy)phenylene vinylene] (MEH-PPV), characterized by high degree of structural order, was synthesized via an organometallic method. The optical properties of the nanocomposite material were comprehensively investigated on solution and on films deposited by spin coating. Remarkably, a significant fluorescence quenching of the polymer at the MEH-PPV/ZnO junction was observed. Photoelectrochemical measurements demonstrated that the photoactivity of the composite material was significantly improved in the case of non-hydrolytic NCs with respect to hydrolytic route prepared ZnO. Moreover, the effective role of the organic/inorganic blend to improve the charge transfer with respect to the double layer hetero-junction was confirmed, thanks to the extended interfaces which enable an effective electron transfer between the hetero-junction components. The system was also studied at different film thicknesses and electrolyte compositions. The results indicated that film photoactivity increased with film thickness up to 300 nm due to the presence of a large number of interfaces, while the change of cation size influenced the ionic conductivity through the nanocomposite film. It was shown that efficient photoconductivity requires not only efficient charge separation, but also efficient transport of the carriers to the electrodes without recombination. (C) 2015 Elsevier B.V. All rights reserved.

The pH-related characteristics of 4-thiothymidine and its stability during prolonged exposure, at room temperature, to a neon lamp emitting in the 400–700 nm wavelength range were investigated by different spectroscopic techniques (UV-Vis, FTIR-ATR, 1H-NMR) and by ElectroSpray Ionization Mass Spectrometry (ESI-MS). The evaluation of the nucleoside photostability was performed as a control, with the perspective of studying its reactivity under the same conditions but in the presence of visible lightabsorbing photosensitizers, able to generate reactive oxygen species. The comparison between UV-Vis spectra recorded at different pH values in the 7–12 range suggested the presence of an equilibrium related to the deprotonation of the N3–H group of 4-thiothymidine, with a pKa estimated to be close to 9. Some effects of the deprotonation occurring at alkaline pH were observed also in FTIR-ATR spectra, the main feature being the appearance of a band related to C]N stretching, interpreted with the assumption of a partial double bond character by C2–N3, N3–C4 and C2–O bonds, as a consequence of negative charge delocalization on the pyrimidine ring. As for photostability, UV-Vis, FTIR-ATR and NMR measurements suggested the generation of thymidine as a by-product but only after a prolonged (48 hours) irradiation time, whereas no significant alteration occurred in a shorter time range (1–2 hours), i.e. the one that will be considered in future studies involving the presence of photosensitizers. The nucleoside stability up to 2 hours of irradiation was confirmed by ESI-MS analyses; furthermore, on the other hand, the latter indicated the presence of three additional by-products, besides thymidine, after 48 hours of irradiation. In particular, an hydroxylated form of 4-thiothymidine and two dimeric species, characterized by S–S and S–O covalent bridges between two 4-thiothymidine and a 4-thiothymidine and a thymidine molecule, respectively, were detected.

The interaction of ochratoxin A (OTA) with heptakis-2,6-di-O-methyl-β-cyclodextrin (DIMEB) in aqueous solutions at two different pHs (3.5 and 9.5) was studied by means of spectroscopic, calorimetric and electrochemical techniques. DIMEB affected the physico-chemical properties of OTA. A stronger interaction was observed at pH = 3.5 where the neutral form of OTA prevails. The spectroscopic information indicated that the OTA/DIMEB inclusion process occurred through the insertion of the phenylalanine group into the cyclodextrin (CD) cavity; moreover, voltammetry experiments showed that the isocoumarinic phenolic group was also involved, probably by non-inclusion interactions. At pH = 3.5, binding constants and thermodynamic parameters of the OTA/DIMEB complex were determined by means of the modified Benesi-Hildebrand equation and van’t Hoff plot. A 1:1 stoichiometry for the OTA/DIMEB complex was observed with a binding constant equal to 530 ± 50 L·mol−1 at 25 °C. The calculated thermodynamic parameters indicate that the interaction is highly endothermic and that the complex formation is driven by entropy. The results provide useful information for potential applications of cyclodextrins in the analysis of mycotoxins and in the field of mycotoxin sequestering agents

Cold plasmas are continuously developed for biomaterials engineering as well as for therapeutic treatments of cells and tissues. For this last application plasma activated media (PAM) and reactive oxygen and nitrogen species (RONS) gained attention as key players. Here, the use of cold atmospheric pressure (AP) plasma is described, for generating RONS in Dulbecco's Modified Eagles Medium (DMEM); superoxide anion (O2-), hydrogen peroxide (H2O2), nitrates (NO3-), and nitrites (NO2-) were detected. PAM was applied to Bone Marrow Stem Cells (BMSC) and SAOS-2 osteoblasts. Both native and plasma-modified polymeric scaffolds were used as three dimensional (3D) supports for cell cultures. The cell activity was found dependent on both PAM and cell type. BMSCs grown on plasma-coated scaffolds tolerated better PAM with respect to those on native scaffolds

Porous alumosilicate aggregate, namely perlite, was used as an alternative material in wastewater treatments for the selective removal of ionic pollutants such as lead which is present in industrial wastewaters and toxic at relatively low concentrations. Metal retention was investigated by single metals and multispecies equilibrium isotherms (batch system) and by carrying out dynamic (column) experiments. Lead ions were supposedly preferentially retained by ion exchange at the negatively charged silicate functional groups present on the perlite material, and to a minor extent by weak electrostatic (Van der Waals) interactions at non-specific functionalities. In the case of the batch system, the Freundlich isotherm gave a good correlation of the experimental data and lead maximum retention (qmax) in single ion solution was 4.28 mg/gperlite, and in multimetal solution was 1.50 mg/gperlite. In the case of the column system, overall capacity was 3.7 mg/gperlite in single ion solution, and in multimetal solution was 3.0 mg/gperlite. In multimetal solutions, lead ions showed the best interaction at the perlite functional groups because of the lowest free energies of hydration and hydrated radius. After sorption, perlite beads were used as lightweight aggregates for cement mortars after evaluation of the potential release of lead ions from the conglomerates.

Alginate-chitosan beads were used as adsorbent to remove two azo anionic textile dyes, Direct Blue 78 and Direct Yellow 106, from aqueous solutions. Batch mode experiments of dyes adsorption were performed and the effects of various parameters such as contact time, adsorbent dosage, initial dye concentration, pH and temperature were examined. Successively, the dyes have been desorbed from the adsorbent and were recycled to dye a cotton fabric. The maximum efficiencies in dye removal, performed at pH 6, 298 K and with 0.5 g of adsorbent, were found to be about 97% for Direct Blue 78 and about 86% for Direct Yellow 106, respectively. The adsorption isotherms fitted the Freundlich’s model, the adsorption kinetics followed the pseudo-second order model and experimental data indicated an exothermic adsorption process. Moreover, the dyes desorption experiments from the alginatechitosan beads demonstrated that about 50% of dyes were released in distilled water at high temperature (368 K) and the colored solutions obtained were so reused in dyeing tests. The results demonstrated that the alginate-chitosan beads are very efficient systems able not only to remove dyes from wastewater, but also to recycle and reuse them in further dyeing processes.

Fully fluorinated arylenevinylene polymers have been synthesized via a methodology based on the Stille cross-coupling reaction and characterized by FTIR spectroscopy and MALDI-TOF mass spectrometry. Investigation of thin film properties by cyclic voltammetry and ellipsometry shows that complete substitution of hydrogen atoms with fluorine atoms on the conjugated backbone of the poly(arylenevinylene) s results in a strong increase of the band gap.

This article describes the synthesis and properties of the first poly(arylene-vinylene)-based sensitizers for application in dye-sensitized solar cells (DSSC). The polymers were prepared by the Suzuki–Heck copolymerization of potassium vinyltrifluoroborate (PVTB) with a mixture of dibromoaryl comonomers designed to obtain macromolecules able to bind onto the photoelectrode by means of carboxyphenylene units. The copolymerization reactions were carried out in the presence of an excess of PVTB to lower the molecular weights of the polymers, which were obtained as soluble materials. The polymers poly[(9,9-didodecyl-2,7-fluorenylene)-vinylene-co-(carboxy- 2,5-phenylene)-vinylene] (P1), poly[(9,9-didodecyl-2,7-fluorenylene)- vinylene-co-(carboxy-2,5-phenylene)-vinylene-co-(4,7- benzothiadiazolylene)-vinylene] (P2), and poly[(9,9-didodecyl- 2,7-fluorenylene)-vinylene-co-(carboxy-2,5-phenylene)-vinyleneco- 2,5-thienylene-vinylene] (P3) were used in DSSC devices, obtaining conversion efficiencies up to 0.88% (P3).