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An AlMo0.5NbTa0.5TiZr baseline alloy was shown earlier to have good high temperature strength but poor ductility below 600 °C due to coarse intermetallic grain boundary particles and a continuous ordered B2 matrix phase. Systematic composition changes intended to remove the deleterious microstructural features and to improve mechanical properties were explored in the present work. The baseline alloy and the new alloys studied here, AlMo0.5NbTa0.5TiZr0.5, AlNbTa0.5TiZr0.5, Al0.5Mo0.5NbTa0.5TiZr and Al0.25NbTaTiZr, all had an ordered B2 matrix crystal structure. Additionally, coherent BCC nanoscale precipitates were present at a high volume fraction inside the B2 matrix grains in AlMo0.5NbTa0.5TiZr, Al0.5Mo0.5NbTa0.5TiZr and Al0.25NbTaTiZr, and/or coarse, grain-boundary particles existed in AlMo0.5NbTa0.5TiZr and AlMo0.5NbTa0.5TiZr0.5. The mechanical properties were assessed with microhardness and compression testing at 25 °C and 1000 °C. Al0.5Mo0.5NbTa0.5TiZr showed the highest hardness (Hv = 6.4 GPa) and strength (σ0.2 = 2350 MPa) at 25 °C and modest strength (σ0.2 = 579 MPa) at 1000 °C. AlMo0.5NbTa0.5TiZr0.5 had the highest strength (σ0.2 = 935 MPa) at 1000 °C, but was brittle at 25 °C. High-temperature deformation produced a desirable microstructure in Al0.5Mo0.5NbTa0.5TiZr and Al0.25NbTaTiZr alloys consisting of a continuous BCC phase and discontinuous B2 nano-precipitates. The relationships between the composition, microstructure, and properties were identified and discussed. Keywords: High entropy alloy, Superalloy, Microstructure, Mechanical properties

The recently developed refractory multi-principle element alloy (MPEA), AlMo$_{0.5}$NbTa$_{0.5}$TiZr, shows an interesting microstructure with cuboidal precipitates of a disordered phase (${\beta}$, bcc) coherently embedded in an ordered phase (${\beta}'$, B2) matrix, unlike the conventional Ni-based superalloys where the ordered phase (${\gamma}'$, L12) is the precipitate phase and the disordered phase (${\gamma}$, fcc) is the matrix phase. It becomes critical to understand the phase transformation pathway (PTP) leading to this microstructure in order to tailor the microstructure for specific engineering applications. In this study, we first propose a possible PTP leading to the microstructure and employ the phase-field method to simulate microstructural evolution along the PTP. We then explore possible PTPs and materials parameters that lead to an inverted microstructure with the ordered phase being the precipitate phase and the disordered phase being the matrix phase, a microstructure similar to those observed in Ni-based superalloys. We find that in order to maintain the precipitates as highly discrete particles along these PTPs, the volume fraction of the precipitate phase needs to be smaller than that of the matrix phase and the elastic stiffness of the precipitate phase should be higher than that of the matrix phase., Comment: Preprint submitted to Applied Physics Letters (14 pages, 6 figures)

Electron microscopy, X-ray energy dispersive spectroscopy, and tomographic reconstructions were used to characterize a high entropy alloy predominantly composed of refractory elements. The intragranular microstructure was found to consist of a periodic two phase mixture, where a disordered bcc phase is aligned orthogonally in an ordered B2 phase. The phases were found to exhibit continuous lattice registry and an orientation relationship given by bcc// B2, {001}bcc//{001}B2. X-ray energy dispersive spectroscopy was used to determine the compositions of the phases, and spectral images were used in the tomographic reconstruction of the alloy to reveal the morphology and the elemental partitioning between phases.

The microstructure of a high entropy alloy with composition of Mo0.5Al1Nb1Ta0.5Ti1Zr1 (the digits refer to molar volumes) has been characterised directly in three dimensions using TEM dark field (DF) imaging and by recording tilt pair micrographs using STEM high angle annular DF (HAADF) imaging. The microstructure contains disordered bcc precipitates that appeared as orthogonal stacks of plate-like features. A tapered needle sample was prepared in a focused ion beam/SEM and was used to acquire a 180° tomographic dataset of STEM/HAADF images in 2° increments. The tilt series images were registered, and the algebraic reconstruction technique was used to reconstruct the three-dimensional microstructure. The bcc precipitates were segmented using a combinative approach involving two threshold techniques. The precipitates were then visualised using commercial software, which revealed surprisingly the existence of both cuboidal and plate-like morphologies. Colouring each precipitate according to its morp...

Stormwater runoff contains a broad range of micropollutants. In Europe a number of these substances are regulated through the Water Framework Directive, which establishes Environmental Quality Standards (EQSs) for surface waters. Knowledge about discharge of these substances through stormwater runoff and combined sewer overflows (CSOs) is essential to ensure compliance with the EQSs. Results from a screening campaign including more than 50 substances at four stormwater discharge locations and one CSO in Copenhagen are reported here. Heavy metal concentrations were detected at levels similar to earlier findings, e.g., with copper found at concentrations up to 13 times greater than the Danish standard for surface waters. The concentration of polyaromatic hydrocarbons (PAHs) exceeded the EQSs by factors up to 500 times for stormwater and 2,000 times for the CSO. Glyphosate was found in all samples whilst diuron, isoproturon, terbutylazine and MCPA were found only in some of the samples. Diethylhexylphthalate (DEHP) was also found at all five locations in concentrations exceeding the EQS. The results give a valuable background for designing further monitoring programmes focusing on the chemical status of surface waters in urban areas.

Rapid Environmental Assessment (REA) includes the use of satellite, airborne, and in situ observations together with geophysical models to provide the best possible estimate of the prevailing conditions during a military operation. Increasingly, the focus is on analysis (nowcasting) and short term forecasting. Requirements vary widely however, depending on the types of vessels involved and the nature of the operation. We have worked closely with the Royal Norwegian Navy (RNoN) to develop a REA capability for high latitudes to meet the requirements of the RNoN.

Background: In the vast majority of psoriatic patients, psoriatic lesions are localised on the body as well as on the scalp. Therefore, safety data on the combined use of calcipotriol in lotion and calcipotriol in ointment are needed. Objective: This study investigated the effect of high-dose treatment with a combination of calcipotriol ointment and scalp solution on calcium metabolism, indices of bone turnover and PASI in patients with extensive psoriasis. Methods: Following a 2-week wash-out period, 88 patients were randomised to 4 weeks of treatment with either calcipotriol ointment/scalp solution (80–100 g/week and 30–50 ml/week, respectively; n = 41) or with a dithranol/tar regimen (n = 47). Patients were seen at weeks 1, 2 and 4 during treatment and 1 week following cessation of treatment. Results: No significant differences at the end of treatment were found between the 2 groups with respect to 24-hour urinary excretion of calcium (expressed as calcium/creatinine ratio), phosphate or pyridinoline, serum concentrations of calcium (albumin corrected), creatinine, phosphate, parathyroid hormone, 25-hydroxyvitamin D3, 1,25-dihydroxyvitamin D3, osteocalcin, alkaline phosphatase (total and bone-specific iso-enzymes) or 1-collagen telopeptide. At the end of treatment, the psoriasis area and severity index had decreased by 57.4% in the calcipotriol group and by 36.1% in the dithranol/tar group (p = 0.004). Investigators’ and patients’ assessments of overall efficacy also favoured treatment with calcipotriol (p < 0.001). Conclusion: The combined use of calcipotriol ointment/scalp solution did not affect the indices of calcium metabolism or bone turnover and was significantly more effective than dithranol/tar in reducing disease severity and extent in patients with extensive psoriasis.

14516 Background: The GnRH receptor blocker degarelix has immediate onset of action in suppressing gonadotropins (LH and FSH), testosterone (T) and prostate specific antigen (PSA) and does not cause T surge. Its long-term efficacy and safety in different maintenance dosing regimens were evaluated in prostate cancer (CaP) patients. Methods: Degarelix was investigated in two multicenter, one-year studies in North America and Europe/South Africa. Degarelix initiation doses of 200 and 240 mg administered subcutaneously, followed by three maintenance doses (80, 120 and 160 mg). Therapeutic effect was assessed by measuring T and PSA levels. 314 patients (age 47–93, median 73 years) with histologically confirmed CaP, PSA ≥2 ng/mL received degarelix subcutaneously every 28 days. Median baseline T was 4.1 ng/mL and PSA was 20 ng/mL. 19% of patients had metastatic, 24% had locally advanced and 30% had localized CaP. 27% were M0/MX and not T-staged. Tumour grade was well differentiated (Gleason 2–4) in 13%, moderately differentiated (5–6) in 38%, and poorly differentiated (7–10) in 49% of the patients. Results: T levels ≤0.5 ng/mL were achieved in 92% of patients at Day 3 and 95% of patients at Day 28 among those treated with 240 mg (40 mg/mL) degarelix. From Day 28 until Day 364, 100% of patients receiving maintenance doses of 160 mg had T levels consistently ≤0.5 ng/mL. No evidence of T surge was detected. PSA decreased by 90% at 8 weeks after starting therapy, 94% at 12 weeks and 96% at 24 weeks. Twelve patients (6%) withdrew from the study due to adverse events, largely related to androgen deprivation. There were no cases of systemic allergic reactions. Conclusion: Degarelix treatment for one year resulted in fast, profound and sustained suppression of T (≤0.5 ng/mL) and fast, profound and sustained reduction of PSA levels. Degarelix was well tolerated without evidence of T surge or systemic allergic reactions. [Table: see text] [Table: see text]