290 research outputs found

    A case study undertaken recycling & reuse of glass fiber reinforced thermoset polumer wastes of composite materials industry

    Get PDF
    Glass fibre-reinforced plastics (GFRP) have been considered inherently difficult to recycle due to both: crosslinked nature of thermoset resins, which cannot be remoulded, and complex composition of the composite itself. Presently, most of the GFRP waste is landfilled leading to negative environmental impacts and supplementary added costs. With an increasing awareness of environmental matters and the subsequent desire to save resources, recycling would convert an expensive waste disposal into a profitable reusable material. In this study, efforts were made in order to recycle grinded GFRP waste, proceeding from pultrusion production scrap, into new and sustainable composite materials. For this purpose, GFRP waste recyclates, were incorporated into polyester based mortars as fine aggregate and filler replacements at different load contents and particle size distributions. Potential recycling solution was assessed by mechanical behaviour of resultant GFRP waste modified polymer mortars. Results revealed that GFRP waste filled polymer mortars present improved flexural and compressive behaviour over unmodified polyester based mortars, thus indicating the feasibility of the GFRP industrial waste reuse into concrete-polymer composite materials

    Pre-B Cell Receptor Signaling Induces Immunoglobulin Îș Locus Accessibility by Functional Redistribution of Enhancer-Mediated Chromatin Interactions

    Get PDF
    During B cell development, the precursor B cell receptor (pre-BCR) checkpoint is thought to increase immunoglobulin Îș light chain (IgÎș) locus accessibility to the V(D)J recombinase. Accordingly, pre-B cells lacking the pre-BCR signaling molecules Btk or Slp65 showed reduced germline VÎș transcription. To investigate whether pre-BCR signaling modulates VÎș accessibility through enhancer-mediated IgÎș locus topology, we performed chromosome conformation capture and sequencing analyses. These revealed that already in pro-B cells the Îș enhancers robustly interact with the ∌3.2 Mb VÎș region and its flanking sequences. Analyses in wild-type, Btk, and Slp65 single- and double-deficient pre-B cells demonstrated that pre-BCR signaling reduces interactions of both enhancers with IgÎș locus flanking sequences and increases interactions of the 3â€ČÎș enhancer with VÎș genes. Remarkably, pre-BCR signaling does not significantly affect interactions between the intronic enhancer and VÎș genes, which are already robust in pro-B cells. Both enhancers interact most frequently with highly used VÎș genes, which are often marked by transcription factor E2a. We conclude that the Îș enhancers interact with the VÎș region already in pro-B cells and that pre-BCR signaling induces accessibility through a functional redistribution of long-range chromatin interactions within the VÎș region, whereby the two enhancers play distinct roles

    Effect of hofmeister ions on transport properties of aqueous solutions of sodium hyaluronate

    Get PDF
    Tracer diffusion coefficients obtained from the Taylor dispersion technique at 25.0◩C were measured to study the influence of sodium, ammonium and magnesium salts at 0.01 and 0.1 mol dm−3 on the transport behavior of sodium hyaluronate (NaHy, 0.1%). The selection of these salts was based on their position in Hofmeister series, which describe the specific influence of different ions (cations and anions) on some physicochemical properties of a system that can be interpreted as a salting-in or salting-out effect. In our case, in general, an increase in the ionic strength (i.e., concentrations at 0.01 mol dm−3 ) led to a significant decrease in the limiting diffusion coefficient of the NaHy 0.1%, indicating, in those circumstances, the presence of salting-in effects. However, the opposite effect (salting-out) was verified with the increase in concentration of some salts, mainly for NH4SCN at 0.1 mol dm−3 . In this particular salt, the cation is weakly hydrated and, consequently, its presence does not favor interactions between NaHy and water molecules, promoting, in those circumstances, less resistance to the movement of NaHy and thus to the increase of its diffusion (19%). These data, complemented by viscosity measurements, permit us to have a better understanding about the effect of these salts on the transport behaviour of NaHy. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Fundacao para a Ciencia e a Tecnologia (FCT) through COMPETE Programme (Operational Programme for Competitiveness) [UIDB/QUI/00313/2020]; Ministry of Education, Youth and Sports of the Czech Republic DKRVO [RP/CPS/2020/003]Ministerstvo Ć kolstvĂ­, MlĂĄdeĆŸe a TělovĂœchovy, MĆ MT: RP/CPS/2020/003; Fundação para a CiĂȘncia e a Tecnologia, FCT: UIDB/QUI/00313/202

    High throughput toxicity screening and intracellular detection of nanomaterials

    Get PDF
    EC FP7 NANoREG (Grant Agreement NMP4-LA-2013-310584)Free PMC Article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5215403/With the growing numbers of nanomaterials (NMs), there is a great demand for rapid and reliable ways of testing NM safety—preferably using in vitro approaches, to avoid the ethical dilemmas associated with animal research. Data are needed for developing intelligent testing strategies for risk assessment of NMs, based on grouping and read-across approaches. The adoption of high throughput screening (HTS) and high content analysis (HCA) for NM toxicity testing allows the testing of numerous materials at different concentrations and on different types of cells, reduces the effect of inter-experimental variation, and makes substantial savings in time and cost.info:eu-repo/semantics/publishedVersio

    Magnetocaloric effect in spin-1/2 XXXX chains with three-spin interactions

    Full text link
    We consider the exactly solvable spin-1/2 XXXX chain with the three-spin interactions of the XZX+YZYXZX+YZY and XZY−YZXXZY-YZX types in an external (transverse) magnetic field. We calculate the entropy and examine the magnetocaloric effect for the quantum spin system. We discuss a relation between the cooling/heating efficiency and the ground-state phase diagram of the quantum spin model. We also compare ability to cool/heat in the vicinity of the quantum critical and triple points. Moreover, we examine the magnetocaloric effect for the spin-1/2 XXXX chain with three-spin interactions in a random (Lorentzian) transverse magnetic field.Comment: 10 pages, 8 figure
    • 

    corecore