206 research outputs found

    Preparation of a sepia melanin and poly(ethylene-alt-maleic anhydride) hybrid material as an adsorbent for water purification

    Get PDF
    Meeting the increasing demand of clean water requires the development of novel efficient adsorbent materials for the removal of organic pollutants. In this context the use of natural, renewable sources is of special relevance and sepia melanin, thanks to its ability to bind a variety of organic and inorganic species, has already attracted interest for water purification. Here we describe the synthesis of a material obtained by the combination of sepia melanin and poly(ethylene-alt-maleic anhydride) (P(E-alt-MA)). Compared to sepia melanin, the resulting hybrid displays a high and fast adsorption efficiency towards methylene blue (a common industrial dye) for a wide pH range (from pH 2 to 12) and under high ionic strength conditions. It is easily recovered after use and can be reused up to three times. Given the wide availability of sepia melanin and P(E-alt-MA), the synthesis of our hybrid is simple and affordable, making it suitable for industrial water purification purposes

    Polyphenols as Morphogenetic Agents for the Controlled Synthesis of Mesoporous Silica Nanoparticles

    Get PDF
    Non-surfactant-induced synthesis of mesoporous silica nanoparticles (MSNPs) is gaining increasing interest because of their low toxicity and simple purification compared to conventional surfactant-based methods. Tannic acid (TA), considered as a glucose-derived polyphenol, was first employed a few years ago and has attracted great research interest. Despite recent progress, the mechanisms resulting in the porous structure remain to be elucidated. In this work, we have employed TA and four structurally related polyphenols (gallic acid, ethyl gallate, eudesmic acid, and quercetin) to elucidate the effect of the chemical structure and properties of polyphenols on their templating ability. Our results unravel the mechanism of MSNP formation templated by TA, which form a supramolecular framework as the skeleton for the silica species to attach. The structure of the supramolecular network results in irregular pores. Additionally, the pKa value of the templates may be accounted for the particle size. Small-angle X-ray scattering was used to provide precise information on the morphology, especially the porosity of the resulting MSNPs in addition to electron microscopy, dynamic light scattering, nitrogen adsorption and desorption Brunauer–Emmett–Teller method, and thermogravimetric analysis

    Production of Λ6^{6}_{\Lambda}H and Λ7^{7}_{\Lambda}H with the (Kstop−^{-}_{stop},π+\pi^+) reaction

    Full text link
    The production of neutron rich Λ\Lambda-hypernuclei via the (Ks−topK^-_stop,π+\pi^+) reaction has been studied using data collected with the FINUDA spectrometer at the DAΦ\PhiNE ϕ\phi-factory (LNF). The analysis of the inclusive π+\pi^+ momentum spectra is presented and an upper limit for the production of Λ6^6_\LambdaH and Λ7^7_\LambdaH from 6^6Li and 7^7Li, is assessed for the first time.Comment: 11 pages, 3 figures. Accepted for publication in PL

    A study of the proton spectra following the capture of K−K^- in 6^6Li and 12^{12}C with FINUDA

    Get PDF
    Momenta spectra of protons emitted following the capture of K−K^- in 6^6Li and 12^{12}C have been measured with 1% resolution. The 12^{12}C spectrum is smooth whereas for 6^6Li a well defined peak appears at about 500 MeV/cc. The first observation of a structure in this region was identified as a strange tribaryon or, possibly, a Kˉ\bar K-nuclear state. The peak is correlated with a π−\pi^- coming from Σ−\Sigma^- decay in flight, selected by setting momenta larger than 275 MeV/cc. The Σ−\Sigma^- could be produced, together with a 500 MeV/cc proton, by the capture of a K−K^- in a deuteron-cluster substructure of the 6^6Li nucleus. The capture rate for such a reaction is (1.62\pm 0.23_{stat} ^{+0.71}_{-0.44}(sys))%/K^-_{stop}, in agreement with the existing observations on 4^4He targets and with the hypothesis that the 6^6Li nucleus can be interpreted as a (d+α)(d+\alpha) cluster.Comment: 21 pages, 10 figures. Accepted for publication in NP

    Communities and patterns of scientific collaboration in Business and Management

    Get PDF
    This is the author's accepted version of this article deposited at arXiv (arXiv:1006.1788v2 [physics.soc-ph]) and subsequently published in Scientometrics October 2011, Volume 89, Issue 1, pp 381-396. The final publication is available at link.springer.com http://link.springer.com/article/10.1007%2Fs11192-011-0439-1Author's note: 17 pages. To appear in special edition of Scientometrics. Abstract on arXiv meta-data a shorter version of abstract on actual paper (both in journal and arXiv full pape

    Community structure and patterns of scientific collaboration in Business and Management

    Get PDF
    This is the author's accepted version of this article deposited at arXiv (arXiv:1006.1788v2 [physics.soc-ph]) and subsequently published in Scientometrics October 2011, Volume 89, Issue 1, pp 381-396. The final publication is available at link.springer.com http://link.springer.com/article/10.1007%2Fs11192-011-0439-1Author's note: 17 pages. To appear in special edition of Scientometrics. Abstract on arXiv meta-data a shorter version of abstract on actual paper (both in journal and arXiv full pape

    Social Cohesion, Structural Holes, and a Tale of Two Measures

    Get PDF
    EMBARGOED - author can archive pre-print or post-print on any open access repository after 12 months from publication. Publication date is May 2013 so embargoed until May 2014.This is an author’s accepted manuscript (deposited at arXiv arXiv:1211.0719v2 [physics.soc-ph] ), which was subsequently published in Journal of Statistical Physics May 2013, Volume 151, Issue 3-4, pp 745-764. The final publication is available at link.springer.com http://link.springer.com/article/10.1007/s10955-013-0722-

    Facile meltPEGylation of flame-made luminescent Tb3+-doped yttrium oxide particles: hemocompatibility, cellular uptake and comparison to silica

    Get PDF
    Flame aerosol technology is a versatile method for scalable synthesis of nanoparticles. Since particles are produced and collected in a dry state, dispersibility and further functionalization could pose hurdles to their biomedical use. We report on a one-pot, scalable and robust procedure for the PEGylation of flame-made yttria and silica nanoparticles. We demonstrate improved colloidal stability, attenuated activation of blood coagulation and decreased uptake into phagocytic cells, all of which pave the way for facilitated biomedical use of flame-made oxide nanoparticles
    • …
    corecore