60 research outputs found

    Immobilization of Monolayer Protected Lipophilic Gold Nanorods on a Glass Surface

    Get PDF
    We present a novel process of immobilization of gold nanorods (GNRs) on a glass surface. Wedemonstrate that by exploiting monolayer protection of the GNRs, their unusual opticalproperties can be completely preserved. UV–visible spectroscopy and atomic forcemicroscopy analysis are used to reveal the optical and morphological properties of monolayerprotected immobilized lipophilic GNRs, and molecular dynamics simulations are used toelucidate their surface molecule arrangements

    Analytical Investigations of XIX–XX century paints. The study of two vehicles from the Museum for Communications of Frankfurt

    Get PDF
    Over the centuries, humans have developed different systems to protect surfaces from the influence of environmental factors. Protective paints are the most used ones. They have undergone considerable development over the years, especially at the turn of the 19th and 20th centuries. Indeed, between the two centuries, new binders and pigments have been introduced in the constituent materials of paints. The years in which these compounds have been introduced and spread in the paint market allow them to be defined as markers for the dating of paints and painted artifacts. The present work is focused on the study of the paints of two vehicles of the Frankfurt Museum of Communication, i.e., a carriage and a cart, that was designed for the German Postal and Telecommunications Service roughly between 1880 and 1920. The characterization of the paints was performed through in situ non-invasive techniques, i.e., portable optical microscopy and multispectral imaging, and laboratory non-destructive techniques, i.e., FT-IR ATR spectroscopy and SEM-EDS. The analytical investigation and the comparison with the data reported in the literature allowed us to determine the historicity of the paints, which are all dated before the 1950s

    Electron and ion spectroscopy of Azobenzene in the valence and core shells

    Get PDF
    Azobenzene is a prototype and building block of a class of molecules of extreme technological interest as molecularphoto-switches. We present a joint experimental and theoretical study of its response to irradiation with light across theUV to X-ray spectrum. The study of valence and inner shell photo-ionization and excitation processes, combined withmeasurement of valence photoelectron-photoion coincidence (PEPICO) and of mass spectra across the core thresholdsprovides a detailed insight onto the site- and state-selected photo-induced processes. Photo-ionization and excita-tion measurements are interpreted via the multi-configurational restricted active space self-consistent field (RASSCF)method corrected by second order perturbation theory (RASPT2). Using static modelling, we demonstrate that thecarbon and nitrogen K edges of Azobenzene are suitable candidates for exploring its photoinduced dynamics thanks tothe transient signals appearing in background-free regions of the NEXAFS and XP

    Early diagnosis of bladder cancer by photoacoustic imaging of tumor-targeted gold nanorods

    Get PDF
    Detection and removal of bladder cancer lesions at an early stage is crucial for preventing tumor relapse and progression. This study aimed to develop a new technological platform for the visualization of small and flat urothelial lesions of high-grade bladder carcinoma in situ (CIS). We found that the integrin alpha 581, overexpressed in bladder cancer cell lines, murine orthotopic bladder cancer and human bladder CIS, can be exploited as a receptor for targeted delivery of GNRs functionalized with the cyclic CphgisoDGRG peptide (Iso4). The GNRs@Chit-Iso4 was stable in urine and selectively recognized alpha 581 positive neoplastic urothelium, while low frequency ultrasound-assisted shaking of intravesically instilled GNRs@Chit-Iso4 allowed the distribution of nanoparticles across the entire volume of the bladder. Photoacoustic imaging of GNRs@Chit-Iso4 bound to tumor cells allowed for the detection of neoplastic lesions smaller than 0.5 mm that were undetectable by ultrasound imaging and bioluminescence

    Improvement of the Adhesion Between TiO2 Nanofilm and Glass Substrate by Roughness Modifications

    Get PDF
    AbstractAn increase of the adhesion between soda-lime glass substrate and TiO2 nanofilm was achieved by roughness modifications, treating the glass surface with acid or basic solutions. The study was organised through a D-optimal experimental design. The roughness (measured by AFM) and the weight loss were statistically analysed using MODDE 9.0 software. Subsequently, the correlation between the surface roughness and the adhesion (measured by scratch test) of the films was studied. The statistic analysis of the results indicates how the chemical treatments modify the roughness of the glasses and it was found that smooth surfaces enhance the adhesion of the films

    Self-cleaning glass prepared from a commercial TiO2 nano-dispersion and its photocatalytic performance under common anthropogenic and atmospheric factors

    No full text
    Nowadays, a wide range of self-cleaning building materials or colloidal solutions for the fabrication of photocalytic coatings are already commercially available. However, some practical limitations still restrict their widespread use in the building sector. For example, in normal household conditions, photocatalytic building materials are exposed to factors that can compromise their efficiency or promote the release of nanoparticles to the environment. In addition, most of the building materials are commonly exposed to atmospheric variables that may greatly differ depending on the geographical zone or the season of the year. In this work, TiO2 films prepared from a commercially available dispersion of nanoparticles were deposited over soda-lime glass substrates. The effects of (i) NaCl residues from the TiO2 nano-dispersion; (ii) treatment with model solutions that simulate the environmental and domestic weathering; (iii) the relative humidity and (iv) the substrate temperature on the photocatalytic activity versus stearic acid were evaluated. The obtained results indicate that these films are more efficient in environments with low humidity levels and relatively high temperatures. Therefore, their commercialization in dry and hot geographic zones would enable the best performance. Furthermore, it was found that these materials can be applied in houses without appreciable loss of efficiency, due to weathering from common cleaning agents or atmospheric factors, like rain or acid rain

    Integrable systems in statistical mechanics

    No full text

    REACTIVITIES OF CARBONATES WITH ILLITE AND KAOLINITE IN MONOPOROSA WALL TILES

    No full text
    The authors carried out a study to investigate the behaviour of three industrial bodies (two monoporosa bodies and one double firing body) which differ principally in their carbonate content. Moreover four different binary mixtures containing illitic or kaolinitic clay and calcite or dolomite were prepared to investigate their reactivity during firing. In this study it has been observed that ghelenite and anorthite were formed in all samples as new phases and MgO residues remain inside monoporosa and fast double firing products after heat treatment in the sample containing dolomite
    • …
    corecore