Search results for " Coating."
showing 10 items of 2558 documents
DELAYED ELECTRON EMISSION OF NEGATIVELY CHARGED TUNGSTEN CLUSTERS
1996
The delayed electron emission of negatively charged tungsten clusters has been investigated on a time scale from 1 to 500 ms. After being stored in a Penning trap clusters ions [Formula: see text] were heated via multiphoton absorption (hν=1.81 eV). In contrast to alkali and coinage metals no photofragmentation could be detected. Instead, for all cluster sizes studied so far only a decrease in the initial ion intensity as a function of time after excitation was observed. This decrease is not caused by ion loss from the trap, but has to be attributed to neutralization via delayed electron emission. The presented results strongly suggest that this process can be viewed as “thermionic emissio…
Single- and Double-Strand Breaks of Dry DNA Exposed to Protons at Bragg-Peak Energies
2017
International audience; Ultrathin layers (<20 nm) of pBR322 plasmid DNA were deposited onto 2.5 μm thick polyester films and exposed to proton Bragg-peak energies (90–3000 keV) at various fluences. A quantitative analysis of radio-induced DNA damage is reported here in terms of single- and double-strand breaks (SSB and DSB, respectively). The corresponding yields as well as G-values and the cross sections exhibit fairly good agreement with the rare available data, stemming from close experimental conditions, namely, based on α particle irradiation. SSB/DSB rates appear to be linear when plotted against linear energy transfer (LET) in the whole energy range studied. All the data present a ma…
High-Pressure Properties of Wolframite-Type ScNbO4
2022
In this work, we used Raman spectroscopic and optical absorption measurements and first-principles calculations to unravel the properties of wolframite-type ScNbO4 at ambient pressure and under high pressure. We found that monoclinic wolframite-type ScNbO4 is less compressible than most wolframites and that under high pressure it undergoes two phase transitions at ∼5 and ∼11 GPa, respectively. The first transition induces a 9% collapse of volume and a 1.5 eV decrease of the band gap energy, changing the direct band gap to an indirect one. According to calculations, pressure induces symmetry changes (P2/c–Pnna–P2/c). The structural sequence is validated by the agreement between phonon calcul…
Application of a polymer-based photocatalytic coating for the protection of limestone stones substrates: an exposure study
2022
In the last decades there have been several studies on cultural heritage regarding the performance of protective and consolidating coatings for the prevention of decay. A coating must have several characteristics such as: efficiency, breathability, and must be durable and reversible. In this research work we tried to verify the performance of a commercial protective product such as Fosbuild FBLE 200, which is composed of a TiO2 nanopowder dispersed in an aqueous solution of an acrylic polymer. This product, which exhibits depolluting, antimicrobial, water-repellent and self-cleaning characteristics, has been applied on different lithotypes such as: Carrara marble, Noto and Comiso stone and …
Structural Features of β-Cyclodextrin Solvation in the Deep Eutectic Solvent, Reline
2020
The inherently amphiphilic nature of native cyclodextrins (CDs) determines their peculiar molecular encapsulation features, enabling applications such as targeted drug nanodelivery, aroma protection, etc. On the contrary, it may also lead to poor solubility in water and other organic solvents and to potentially detrimental flocking in these media, thus posing limitations to more extensive usage. Here we use small angle X-ray scattering to show that deep eutectic solvent reline (1:2 choline chloride:urea) succeeds in dissolving large amounts of beta-CD (at least 800 mg/mL, compared with the solubility in water of 18 mg/mL), without aggregation phenomena occurring. At the microscopic level, m…
Antibody recognition of fluorinated MUC1 glycopeptide antigens.
2011
The syntheses of various fluorinated MUC1 glycopeptide antigens and their specific binding to serum antibodies from mice immunized with natural and fluorinated TF(6)-MUC1-TTox conjugate vaccines are presented.
Synthesis of a MUC1-glycopeptide-BSA conjugate vaccine bearing the 3'-deoxy-3'-fluoro-Thomsen-Friedenreich antigen.
2011
A novel MUC1-glycopeptide–BSA conjugate vaccine with a specifically fluorinated Thomsen–Friedenreich antigen side chain at Thr6 was prepared. Preliminary immunological experiments reveal specific binding of the tumor-associated glycopeptide antigen analog by anti-MUC1-mouse antibodies.
Structure−Dynamics Coupling between Protein and External Matrix in Sucrose-Coated and in Trehalose-Coated MbCO: An FTIR Study
2004
We performed FTIR measurements on carboxy-myoglobin (MbCO) embedded in a sucrose−water matrix to study the degrees of freedom coupling between protein and external matrix in such a system. The work was undertaken on the light of recent results by Giuffrida et al. (J. Phys. Chem. B 2003, 107, 13211−13217), who evidenced, in trehalose-coated MbCO, a structured water−sugar environment of the protein, tightly coupled to the heme pocket structure. Such information was obtained through a suitable analysis of the temperature dependence of the CO stretching and of the water association bands in samples of different content of residual water. We applied here the same analysis to sucrose-coated MbCO.…
Tailoring oxide properties: An impact on adsorption characteristics of molecules and metals
2014
Abstract Both density functional theory calculations and numerous experimental studies demonstrate a variety of unique features in metal supported oxide films and transition metal doped simple oxides, which are markedly different from their unmodified counterparts. This review highlights, from the computational perspective, recent literature on the properties of the above mentioned surfaces and how they adsorb and activate different species, support metal aggregates, and even catalyse reactions. The adsorption of Au atoms and clusters on metal-supported MgO films are reviewed together with the cluster׳s theoretically predicted ability to activate and dissociate O 2 at the Au–MgO(100)/Ag(100…
Hydrolate and EO Application to Reduce Decay of Carica papaya during Storage
2023
Postharvest fruit loss is caused by the absence of advanced handling and storage technologies and the quiescent presence of fungal pathogens. Therefore, there is a growing demand for sustainable decisions for the planet. This study focused on the use of two types of edible coatings: one was based on the essential oil of Origanum vulgare L. subsp. viridulum with Aloe arborescens Mill. gel (EC1), and the other was based on the hydrolate only (EC2). These treatments were applied to provide defense against fungal infections in papaya (Carica papaya L. cv Solo), and the storage time was 25 days (T5 ± 1 °C). Fruits coated with EC1 were more contaminated with fungal pathogens than both control (CT…