Malloyhirsch2615

Such an all-in-one electrode with impressive photovoltaic properties provides a promising platform for PEC applications with high efficiency, eco-friendly, excellent stability and low cost. © 2020 IOP Publishing Ltd.Orientational disorder of the molecular carbonate anions in BaCO3, which occurs naturally as the mineral witherite, has been studied using a combination of neutron total scattering analysed by the Reverse Monte Carlo method and molecular dynamics simulations. The primary focus is on the phase transition to the cubic phase, which assumes a rocksalt structure (Strukturbericht type B1) with highly disordered orientations consistent with the mismatch between the site (m3m) and molecular (3/m) symmetries. Both experiment and simulation show a high degree of disorder, with the C-O bond orientation distribution never exceeding 25% variation from that of a completely uniform distribution, although there are differences between the two methods regarding the nature of these variations. Molecular dynamics simulations are also reported for the analogous phase transitions in the very important mineral calcite, CaCO3. The combination of the simulations and comparison with BaCO3 shows that the properties of calcite at all temperatures within its stability field are affected mostly by the onset of orientational disorder associated with the high-temperature cubic phase, even though this lies outside the stability field of calcite. This is a new understanding of calcite, which previously had been interpreted purely in terms of the phase transition to an intermediate partially-disordered phase. Finally, we also found that witherite itself appears to support the development of orientational disorder on heating, with the simulations showing a sequence of phase transitions that explain the much larger thermal expansion of one axis. Creative Commons Attribution license.We investigated the specific electronic energy deposition by protons and He ions with keV energies in different transition metal nitrides of technological interest. Data were obtained from two different time-of-flight ion scattering setups and show excellent agreement. For protons interacting with light nitrides, i.e. TiN, VN and CrN, very similar stopping cross sections per atom were found, which coincide with literature data of N2 gas for primary energies ≤ 25 keV. In case of the chemically rather similar nitrides with metal constituents from the 5th and 6th period, i.e. ZrN and HfN, the electronic stopping cross sections were measured to exceed what has been observed for molecular N2 gas. For He ions, electronic energy loss in all nitrides was found to be significantly higher compared to the equivalent data of N2 gas. Additionally, deviations from velocity proportionality of the observed specific electronic energy loss are observed. A comparison with predictions from density functional theory for protons and He ions yields a high apparent efficiency of electronic excitations of the target for the latter projectile. These findings are considered to indicate the contributions of additional mechanisms besides electron hole pair excitations, such as electron capture and loss processes of the projectile or promotion of target electrons in atomic collisions. © 2020 IOP Publishing Ltd.The electronic states of self-activated titanate phosphors (Ba2TiSi2O8, Sr2TiSi2O8, and Na2TiSiO5) were investigated by Ti K-edge X-ray absorption spectroscopy under ultraviolet (UV) irradiation in order to unveil the photoluminescence mechanism in the absence of particular atomic color centers. The overall spectral features of all samples were identical, main edges and large pre-edges corresponding to the Ti 4pand Ti 3dstates, respectively. The pre-edge peak of Sr2TiSi2O8shifted toward lower energy by 0.2 eV compared with the other two samples, corresponding to a red shift of the photoluminescence spectrum. In the region between these features, a small hump was observed for each sample, which gradually diminishes as a function of UV power. The hump can be attributed to the Ti 4pstate based on the calculated electron density of states determined by multiple scattering theory, and this hump serves as a trap for UV-excited electrons. © 2020 IOP Publishing Ltd.We present a systematic investigation on the enhancement of the quality (Q) factors for guided-mode resonance (GMR) sensors with shallow subwavelength grating structures. By introducing the coupled-mode model, a theoretical high-Q factor can be achieved by choosing the proper geometric structure. Based on this method, a GMR sensor with a Q factor up to 8000, which is an order of magnitude larger than those of typical GMR sensors with Q factors within 100~300, was demonstrated experimentally. Besides, the approached GMR sensor achieved a bulk sensitivity of 135 nm/RIU with a high signal to noise ratio, which supports a detection limit of 1 ng/mL for bovine serum albumin detection. Temsirolimus nmr © 2020 IOP Publishing Ltd.OBJECTIVE Electrical Impedance Tomography (EIT) typically reconstructs individual images from electrical voltage measurements at pairs of electrodes due to current driven through other electrode pairs on a body. EIT images have low spatial resolution, but excellent temporal resolution. There are four methods for integrating temporal data into an EIT reconstruction filtering over measurements, filtering over images, combined spatial and temporal (spatio-temporal) regularization, and Kalman filtering. These spatio-temporal methods have not been directly compared, making it difficult to evaluate relative performance and choose an appropriate method for particular use cases. APPROACH We (1)develop a common framework, (2)develop comparison metrics, (3)perform simulation and tank studies which directly compare algorithms, and (4)report on relative advantages of the different algorithms. MAIN RESULTS Temporal filtering is well understood, but often not considered as part of the imaging process despite a direct impacas become an important EIT technique where temporal and spatial aspects of analysis are tightly integrated. This work gives guidance on available methods and suggests directions for future research. © 2020 Institute of Physics and Engineering in Medicine.