1,142 research outputs found
Renfrew Close Rain Gardens – Year two monitoring and project evaluation report, May 2017.
The Renfrew Close rain gardens are a community scale, sustainable drainage (SuDs) scheme, in the London Borough of Newham. This was the first large scale retrofit of a raingarden in the borough and was implemented through a partnership consisting of the Environment Agency, the London Borough of Newham, Groundwork London and Thames Water. The Sustainability Research institute at UEL has monitored the hydrological performance of the rain gardens over two years.
The report presents results obtained from the second year of monitoring, covering the period of April 2015 – March 2017, and comments on the basin performance and lessons learned over the two years
An atomic scale comparison of the reaction of Bioglass® in two types of simulated body fluid
A class of melt quenched silicate glasses, containing calcium, phosphorus and alkali metals, and having the ability to promote bone regeneration and to fuse to living bone, is produced commercially as Bioglass. The changes in structure associated with reacting the bioglass with a body fluid simulant (a buffered Tris(hydroxymethyl)aminomethane growth medium solution or a blood plasma-like salt simulated body fluid) at 37°C have been studied using both high energy and grazing incidence x-ray diffraction. This has corroborated the generic conclusions of earlier studies based on the use of calcia–silica sol-gel glasses whilst highlighting the important differences associated with glass composition; the results also reveal the more subtle effects on reaction rates of the choice of body fluid simulant. The results also indicate the presence of tricalcium phosphate crystallites deposited onto the surface of the glass as a precursor to the growth of hydroxyapatite, and indicates that there is some preferred orientation to their growth
Influence of waste glass in the foaming process of open cell porous ceramic as filtration media for industrial wastewater
This paper reports the development and testing results of a prototype ceramic filter with excellent sorption properties (<99% elimination in 5 min) leading to good efficacy in the removal of industrial contaminants (Reactive Bezaktiv Turquoise Blue V-G (BTB) dye). The novelty in the investigation lies in developing the filter material obtained from the recycling of waste glass combined with highly porous open-cell clay material. This newly developed material showed a significant reduction in the energy requirements (sintering temperature required for the production of industrial filters) thus addressing the grand challenge of sustainable and cleaner manufacturing. The methodology entails sintering of the clay foam (CF) at temperatures ranging from 800 to 1050 °C and blending it with 5%, 7% and 10 wt% milled glass cullet. One of the aims of this investigation was to evaluate and analyse the effect of the pH of the solution, contact time and equilibrium isotherm on the sorption process and the mechanical compressive strength, porosity, water uptake. From the kinetic studies, it was discovered that the experimental results were well aligned with the pseudo-second-order model and chemisorption was discovered to be a mechanism driving the adsorption process. These findings are crucial in designing cost-effective industrial filtration system since the filter material being proposed in this work is reusable, recyclable and readily available in abundance. Overall, the pathway for the reuse of waste glass shown by this work help address the sustainability targets set by the UN Charter via SDG 6 and SDG 12
The MemProtMD database : a resource for membrane-embedded protein structures and their lipid interactions
Integral membrane proteins fulfil important roles in many crucial biological processes, including cell signalling, molecular transport and bioenergetic processes. Advancements in experimental techniques are revealing high resolution structures for an increasing number of membrane proteins. Yet, these structures are rarely resolved in complex with membrane lipids. In 2015, the MemProtMD pipeline was developed to allow the automated lipid bilayer assembly around new membrane protein structures, released from the Protein Data Bank (PDB). To make these data available to the scientific community, a web database (http://memprotmd.bioch.ox.ac.uk) has been developed. Simulations and the results of subsequent analysis can be viewed using a web browser, including interactive 3D visualizations of the assembled bilayer and 2D visualizations of lipid contact data and membrane protein topology. In addition, ensemble analyses are performed to detail conserved lipid interaction information across proteins, families and for the entire database of 3506 PDB entries. Proteins may be searched using keywords, PDB or Uniprot identifier, or browsed using classification systems, such as Pfam, Gene Ontology annotation, mpstruc or the Transporter Classification Database. All files required to run further molecular simulations of proteins in the database are provided
Probing vibrational modes in silica glass using inelastic neutron scattering with mass contrast
The effective vibrational density of states (VDOS) has been derived from inelastic neutron-scattering data, for isotopically substituted Si O 18 2 and Si O 16 2 glasses, to gain information about the relative contribution to the Si and O partial VDOS. This is a necessary point of comparison for vibrational mode analyses of molecular-dynamics models. The mass contrast has led to a measurable shift between vibrational mode frequencies in the effective VDOS of Si O 18 2 and Si O 16 2, which is well reproduced in an ab initio simulation. The vibrational band centered at 100.2 meV is confirmed to have significantly lower contribution from the oxygen partial VDOS, than the higher (150.3 and 135.8 meV) and lower energy bands (53.3 meV)
Effect of silver content on the structure and antibacterial activity of silver-doped phosphate-based glasses
Staphylococcus aureus can cause a range of diseases, such as osteomyelitis, as well as colonize implanted medical devices. In most instances the organism forms biofilms that not only are resistant to the body's defense mechanisms but also display decreased susceptibilities to antibiotics. In the present study, we have examined the effect of increasing silver contents in phosphate-based glasses to prevent the formation of S. aureus biofilms. Silver was found to be an effective bactericidal agent against S. aureus biofilms, and the rate of silver ion release (0.42 to 1.22 µg·mm–2·h–1) from phosphate-based glass was found to account for the variation in its bactericidal effect. Analysis of biofilms by confocal microscopy indicated that they consisted of an upper layer of viable bacteria together with a layer (20 µm) of nonviable cells on the glass surface. Our results showed that regardless of the silver contents in these glasses (10, 15, or 20 mol%) the silver exists in its +1 oxidation state, which is known to be a highly effective bactericidal agent compared to that of silver in other oxidation states (+2 or +3). Analysis of the glasses by 31P nuclear magnetic resonance imaging and high-energy X-ray diffraction showed that it is the structural rearrangement of the phosphate network that is responsible for the variation in silver ion release and the associated bactericidal effectiveness. Thus, an understanding of the glass structure is important in interpreting the in vitro data and also has important clinical implications for the potential use of the phosphate-based glasses in orthopedic applications to deliver silver ions to combat S. aureus biofilm infections
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Multiple rare-earth ion environments in amorphous (Gd2O3)(0.230)(P2O5)(0.770) revealed by gadolinium K-edge anomalous x-ray scattering
A Gd K-edge anomalous x-ray scattering (AXS) study is performed on the rare-earth (R) phosphate glass, (Gd2O3)0.230(P2O5)0.770, in order to determine Gd⋯Gd separations in its local structure. The minimum rare-earth separation is of particular interest given that the optical properties of these glasses can quench when rare-earth ions become too close to each other. To this end, a weak Gd⋯Gd pairwise correlation is located at 4.2(1)Å, which is representative of a metaphosphate R⋯R separation. More intense first-neighbor Gd⋯Gd pairwise correlations are found at the larger radial distributions, 4.8(1), 5.1(1), and 5.4(1)Å. These reflect a mixed ultraphosphate and metaphosphate structural character, respectively. A second-neighbor Gd⋯Gd pairwise correlation lies at 6.6(1)Å which is indicative of metaphosphate structures. Meta- and ultraphosphate classifications are made by comparing the R⋯R separations against those of rare-earth phosphate crystal structures, R(PO3)3 and RP5O14, respectively, or difference pair-distribution function (ΔPDF) features determined on similar glasses using difference neutron-scattering methods. The local structure of this glass is therefore found to display multiple rare-earth ion environments, presumably because its composition lies between these two stoichiometric formulae. These Gd⋯Gd separations are well-resolved in ΔPDFs that represent the AXS signal. Indeed, the spatial resolution is so good that it also enables the identification of R⋯X(X=R, P, O) pairwise correlations up to r∼9Å; their average separations lie at r∼7.1(1), 7.6(1), 7.9(1), 8.4(1), and 8.7(1)Å. This is a report of a Gd K-edge AXS study on an amorphous material. Its demonstrated ability to characterize the local structure of a glass up to such a long range of r heralds exciting prospects for AXS studies on other ternary noncrystalline materials. However, the technical challenge of such an experiment should not be underestimated, as is highlighted in this work where probing AXS signal near the Gd K edge is found to produce inelastic x-ray scattering that precludes the normal AXS methods of data processing. Nonetheless, it is shown that AXS results are not only tractable but they also reveal local structure of rare-earth phosphate glasses that is important from a materials-centered perspective and which could not be obtained by other materials characterization methods.J.M.C. is grateful to the Royal Commission of the Great Exhibition 1851 for a 2014 Design Fellowship hosted by Argonne National Laboratory (ANL) where work done was supported by the U.S. Department of Energy (DOE) Office of Science, Office of Basic Energy Sciences, and X-ray 1-BM beam line of the Advanced Photon Source, which is a DOE Office of Science User Facility, all under Contract No. DE-AC02-06CH11357. J.M.C. and R.J.N. are also indebted to the Engineering and Physical Sciences Research Council Grant No. GR/L41035 for funding
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