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Supercritical n-decane is applied in the regenerative cooling system of scramjet engines while scramjets are always in various irregular movements. With the desire to explore heat transfer performance of supercritical n-decane under actual flight conditions, numerical simulations and analysis of different states during the accelerated flight process are carried out under three different heat fluxe

Paraffin wax and various nanoparticles (CuO, Al2O3 and Fe3O4) were used as matrix and heat conduction enhancer of phase change materials (PCMs), respectively. The dispersant Span 80 was added into the nanocomposite to provide stable PCMs. Based on analyses of melting and freezing curves and infrared thermal imaging tests, the phase change latent heat, viscosity, and thermal conductivity of the nan

We report the evolution of metastable precursor structures during hydrogen infusion in the near-surface region of a super duplex stainless steel. Grazing-incidence x-ray diffraction was employed to monitor, operando, the lattice degradation of the austenite and ferrite phases. Electrochemical hydrogen charging resulted in the splitting of the diffraction peaks of the austenite phase, suggesting th

Wide-viscosity-range impellers have extensive demands and applications in process industry. The gas–liquid dispersion and mass transfer characteristics of wide-viscosity-range impellers including Large-double-blade (LDB) impeller, Fullzone (FZ) impeller and Maxblend (MB) impeller in water solutions of xanthan gum were investigated experimentally and compared. The influences of gas flow rate, impel

A novel kind of regenerative cooling channel, a so-called nested channel, is proposed to further reduce the combustion chamber wall temperature of a scramjet. The supercritical n-decane heat transfer in the horizontal up-channel and horizontal down-channel with different flow directions are numerically investigated. The temperature distribution, flow field, and vortex structure are presented to di

We investigate with in situ surface X-ray diffraction (SXRD) and X-ray reflectivity (XRR) experiments the cathodic stability of an ultrathin single-crystalline IrO2(110) film with a regular array of mesoscopic rooflike structures that is supported on a RuO2(110)/Ru(0001) template. It turns out that the planarity of the single-crystalline IrO2(110) film is lost in that IrO2(110) oxide domains delam

High-resolution X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) were used to characterize IrO2(110) films on Ir(100) with stoichiometric as well as OH-rich terminations. Core-level Ir 4f and O 1s peaks were identified for the undercoordinated Ir and O atoms and bridging and on-top OH groups at the IrO2(110) surfaces. Peak assignments were validated by comparison of the c

Packed beds are widely used in engineering applications due to their high specific surface area and good heat transfer characteristics. A grille-sphere composite packed bed is proposed previously and has been proved to have higher overall heat transfer coefficient than the simple cubic packing structure. In the present paper, the flow inhomogeneities in both the grille-sphere composite packed bed

Background and purpose — We have previously reported on the prosthetic survival of total ankle replacements (TAR) in Sweden performed between 1993 and 2010. Few other reports have been published on 5- and 10-year survival rates. Furthermore, there is a lack of long-term outcome data on modern prosthetic designs. Therefore, we compared early and current prosthetic designs after a mean 7-year follow

The unique diagnostic possibilities of X-ray diffraction, small X-ray scattering and phase-contrast imaging techniques applied with high-intensity coherent X-ray synchrotron and X-ray free-electron laser radiation can only be fully realized if a sufficient dynamic range and/or spatial resolution of the detector is available. In this work, it is demonstrated that the use of lithium fluoride (LiF) a

In this study, thermal and hydraulic performance of supercritical liquefied natural gas (LNG) is numerically studied in a printed circuit heat exchanger (PCHE) with airfoil fins under a rolling condition. Effects of operating pressures and rolling parameters are investigated. Results indicate that the PCHE has better thermal performance but worse hydraulic performance at a lower pressure condition

In this study, the effects of elliptical and super-elliptical film holes on the adiabatic film cooling effectiveness under a density ratio of 2 and blowing ratios 0.5 and 1 are studied. Five different cases are designed by considering various length-to-width ratios and the baseline is the model with cylindrical film hole. The DES with the Realizable k-ε model is adopted for the five cases to inves

In order to make a better understanding of dehydrogenation mechanisms of liquid organic hydrogen carriers, cyclohexane was selected as a model compound to carry out its decomposition studies over Pt(1 1 1), Pd(1 1 1), Rh(1 1 1), and Ni(1 1 1) surfaces via periodic density functional theory calculations. The adsorption geometries and adsorption energies of reaction intermediates were presented. Sim

With the increasing requirements of compressed gas energy storage systems for compressors and expanders, sliding vane rotary compressors are worth trying. To study the influence of different configurations of discharge ports on the performance of compressors, numerical simulations are conducted on the innovative sliding vane compressors with a rotating cylinder. The reliable Renormalization Group

Purpose of Review: This review outlines the scope of the problem in osteoporosis care and secondary fracture prevention and describes fracture prevention strategies, with a focus on the frail elderly. Recent Findings: Despite heightened awareness among patients and clinicians alike and the availability of efficacious anti-osteoporosis medications, osteoporosis is still underdiagnosed and undertrea

Summary: Romosozumab is a novel bone-building drug that reduces fracture risk. This health economic analysis indicates that sequential romosozumab-to-alendronate can be a cost-effective treatment option for postmenopausal women with severe osteoporosis at high risk of fracture. Purpose: To estimate the cost-effectiveness of sequential treatment with romosozumab followed by alendronate (“romosozuma

Osteoporosis-related fractures are undertreated, due in part to misinformation about recommended approaches to patient care and discrepancies among treatment guidelines. To help bridge this gap and improve patient outcomes, the American Society for Bone and Mineral Research assembled a multistakeholder coalition to develop clinical recommendations for the optimal prevention of secondary fracture a

The aim was to investigate embryo-foetal effects of continuous maternal insulin-induced hypoglycaemia extending throughout gestation or until gestation day (GD)17 (typical last day of dosing during pre-clinical evaluation) providing comparator data for safety assessment of longer-acting insulin analogues in non-diabetic rats. Pregnant rats received human insulin (HI)-infusion during gestation unti

Executive function is defined as a set of cognitive skills that are necessary to plan, monitor, and execute a sequence of goal-directed complex actions. Executive function is influenced by a variety of factors, including habitual sleep duration and diabetes. In the present study, we investigated in 18,769 Swedish adults (mean age: 61 y) the association between executive function, diabetes, and sel

With the rapid development of short-pulse intense laser sources, studies of matter under extreme irradiation conditions enter further unexplored regimes. In addition, an application of X-ray Free-Electron Lasers (XFELs) delivering intense femtosecond X-ray pulses, allows to investigate sample evolution in IR pump - X-ray probe experiments with an unprecedented time resolution. Here we present a de