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A method is presented for the determination of complex-valued compression and shear elastic moduli of polymers for ultrasound applications. The resulting values, which are scarcely reported in the literature, are found with uncertainties typically around 1% (real part) and 6% (imaginary part). The method involves a setup consisting of a cm-radius, mm-thick polymer ring glued concentrically to a di
This paper presents experimental results from measurements on circular cylinders of differentdiameters in cross flow. The Reynolds number was varied from about 50 to 2·105. Thecombined effects of Reynolds number and a low-intensity freestream turbulence (Tu =1.4%)on the variation of different coefficients, e.g., Strouhal number, mean and RMS pressurecoefficients, are presented. The results indicat
Research and Development (R&D) in the pharmaceutical sector traditionally occurred in closed, siloed institutional settings. This approach was a function of a rights-oriented model which framed access and reuse of data (data sharing) as a threat to rights-holders. However, a closed model of explorative collaboration is less suited to today’s more complex scientific ecosystem, where external en
Polyoxometalates (POMs), ranging in size from 1 to 10’s of nanometers, resemble building blocks of inorganic materials. Elucidating their complex solubility behavior with alkali-counterions can inform natural and synthetic aqueous processes. In the study of POMs ([Nb24O72H9]15−, Nb24) we discovered an unusual solubility trend (termed anomalous solubility) of alkali-POMs, in which Nb24 is most solu
Niobium oxide thin films have been prepared by spin-coating aqueous solutions of tetramethylammonium salts of the isostructural polyoxometalate clusters [Nb10O28]6-, [TiNb9O28]7- and [Ti2Nb8O28]8- onto silicon wafers, and annealing them. The [Nb10O28]6- cluster yields films of Nb2O5 in the orthorhombic and monoclinic crystal phases when annealed at 800 °C and 1000 °C, respectively, whereas the [Ti
A polycondensation reaction of the orthotungstate anion WO42-, buffered at pH 7.5 in a TRIS-HCl (0.15 M) solution, results in the first example of a discrete polyoxotungstate anion, with just two W ions stabilized with TRIS ligands. It was isolated and characterized as Na2[WVI2O6(C4O3NH10)2]·6H2O by single-crystal and powder X-ray diffraction, FT-IR spectroscopy, thermogravimetrical analysis (TGA)
Pro-inflammatory and amyloidogenic S100A9 protein is central to the amyloid-neuroinflammatory cascade in neurodegenerative diseases. Polyoxometalates (POMs) constitute a diverse group of nanomaterials, which showed potency in amyloid inhibition. Here, we have demonstrated that two selected nanosized niobium POMs, Nb10 and TiNb9, can act as potent inhibitors of S100A9 amyloid assembly. Kinetics ana
Microwave preparation of polyoxoniobates and -tantalates afford a more rapid alternative to conventional hydrothermal methods of synthesis, in addition to allowing for the use of anhydrous niobium pentoxide in lieu of niobic acid, albeit with diminished yields. Limitations associated with the pH at which different oxides can be activated and how this affects the accessibility of different products
Based on extensive experimental investigations on many different oxide nanoparticles, it is now a well-established view that the counter-ions exhibit ion specific effects due to their high charge density and strong interaction with oppositively charged surfaces. On the other hand, studies regarding co-ion effects are scarcely reported in the literature. In this study we have measured the surface c
This paper presents a systematic investigation of the influence of streamturbulence on the pressure forces on a single tube. Grids were used to producedifferent turbulent flow fields with longitudinal integral scale (eddy size)ranging from 0.1 to 0.5 tube diameters and turbulence intensities ranging from0.1 to 3-2 %. The measurements were carried out at two Reynolds numbers, 2.7 - 10 and U.1-104 ,
Calculations of two-dimensional unsteady flow around a quadratic two-dimensional cylinder at zero angle of attack are performed. The Reynolds numbers are low (Re = 45 - 250) so that the flow presumably is laminar. At Re > 50 a von Karman vortex street with a well-defined shedding frequency is predicted. An incompressible SIMPLEC finite volume code employing non-staggered grid arrangement is used.
Introduction Trauma accounts for nearly 10% of the global burden of disease. Several trauma life support programmes aim to improve trauma outcomes. There is no evidence from controlled trials to show the effect of these programmes on patient outcomes. We describe the protocol of a pilot study that aims to assess the feasibility of conducting a cluster randomised controlled trial comparing advanced
Large Eddy Simulations (LESs) of flow around a square cylinder at Re = 22 × 103 are performed employing a dynamic one-equation subgrid model. An implicit fractional step method finite-volume code with second-order accuracy in space and time is used. By using a periodic boundary condition, the spanwise dimension is four times the side length of the cylinder. Some global quantities, such as the domi
2D and 3D unsteady flow past a rigid prism of a squarecross-section with one side facing the oncoming flow is numerically simulated for Reynolds numbers between 200 to 500. An incompressible code is used employing an implicit fractional step method finite-volume with second-order accuracy in space and time. For 2D flow, it is found that, for Re >300, the time-mean flow patterns are not perfectly s
Ruddlesden-Popper perovskites (RPPs) have been demonstrated as a very promising approach for tuning the emission color of perovskite light-emitting diodes (PeLEDs). However, achieving high-performance red PeLEDs with recommendation 2020 color coordinates is still challenging due to the lack of reasonable control over the properties of RPP films. Here, we demonstrate that the judicious selection of
