Monodomain strained ferroelectric PbTiO(3) thin films: Phase transition and critical thickness study

This work demonstrates that instead of paraelectric PbTiO(3), completely c-oriented ferroelectric PbTiO(3) thin films were directly grown on (001)-SrTiO(3) substrates by pulsed-laser deposition with thickness up to 340 nm at a temperature well above the Curie temperature of bulk PbTiO(3). The influence of laser-pulse frequency, substrate-surface termination on growth, and functional properties were studied using x-ray diffraction, transmission electron microscopy, and piezoresponse force microscopy. At low growth rates (frequency 8 Hz) a domains were formed for film thickness above 20-100 nm. Due to coherency strains the Curie temperature (T(c)) of the monodomain films was increased approximately by 350 degrees C with respect to the T(c) of bulk PbTiO(3) even for 280-nm-thick films. Nonetheless, up to now this type of growth mode has been considered unlikely to occur since the Matthews-Blakeslee (MB) model already predicts strain relaxation for films having a thickness of only similar to 10 nm. However, the present work disputes the applicability of the MB model. It clarifies the physical reasons for the large increase in T(c) for thick films, and it is shown that the experimental results are in good agreement with the predictions based on the monodomain model of Pertsev et al. [Phys. Rev. Lett. 80, 1988 (1998)].

Effect of Post-weld Heat-treatment on the Stress Corrosion Cracking Behaviour of Laser-welded Shape Memory NiTi Wires in Hanks’ Solution

In this study, the stress-corrosion cracking (SCC) behaviour of laser-welded NiTi wires before and after post-weld heat-treatment (PWHT) was investigated. The samples were subjected to slow strain rate testing (SSRT) under tensile loading in Hanks’ solution at 37.5 °C (or 310.5 K) at a constant anodic potential (200 mVSCE). The current density of the samples during the SSRT was captured by a potentiostat, and used as an indicator to determine the susceptibility to SCC. Fractography was analyzed using scanning-electron microscopy (SEM). The experimental results showed that the laser-welded sample after PWHT was immune to the SCC as evidenced by the stable current density throughout the SSRT. This is attributed to the precipitation of fine and coherent nano-sized Ni4Ti3 precipitates in the welded regions (weld zone, WZ and heat-affected zone, HAZ) after PWHT, resulting in (i) enrichment of TiO2 content in the passive film and (ii) higher resistance against the local plastic deformation in the welded regions.

A European Culture War in the Twentieth Century? Antic-Catholicism and Anti-Bolshevism between Moscow, Berlin, and the Vatican 1922 to 1933

The term “culture war” has become a generic expression for secular-catholic conflicts across nineteenth-century Europe. Yet, if measured by acts of violence, anticlericalism peaked in the years between 1927 and 1939, when thousands of Catholic priests and believers were imprisoned or executed and hundreds of churches razed in Mexico, Spain and Russia. This essay argues that not only in these three countries, but indeed across Europe a culture war raged in the interwar period. It takes, as a case study, the interaction of communist and Catholic actors located in the Vatican, the Soviet Union, and Germany in the period between the beginning of the Pontificate of Pius XI in 1922 and Hitler’s appointment as chancellor of Germany in 1933. Using correspondence and reports from the Vatican archives, this essay shows how Papal officials and communist leaders each sought to mobilize the German populace to achieve their own diplomatic ends. German Catholics and communists gladly responded to the call to arms that sounded from Rome and Moscow in 1930, but they did so also to further their own domestic goals. The case study shows how national contexts inflected the transnational dynamics of radical anti-Catholicism in interwar Europe. In the end, agitation against “godlessness” did not lead to the return of a “Christian State” desired by many conservative Christians. Instead, the culture war further destabilized the republic and added a religious dimension to a landscape well suited to National Socialist efforts to reach a Christian population otherwise mistrustful of its völkisch and anticlerical elements.

The Double Life of Duke of Somerset v Cookson, or a Legal Excavation of the Corbridge Lanx

Duke of Somerset v Cookson (1735) occupies an important place in English legal history as a leading authority for Chancery jurisdiction to order specific delivery of movable property where an award of damages would be inadequate. The property at issue was the Corbridge lanx, now in the British Museum, but then claimed as treasure trove by the duke of Somerset as lord of the manor of Corbridge. This paper re-examines Cookson as the first reported English decision relating to treasure trove, and uses later treasure trove claims by the duke of Somerset's successors to the manor of Corbridge, the dukes of Northumberland, to shed fresh light on the 1735 decision and on the development of treasure trove practice from the eighteenth century onwards.

Low pressure methane solubility in lithium-ion batteries based solvents and electrolytes as a function of temperature. Measurement and prediction

The methane solubility in five pure electrolyte solvents and one binary solvent mixture for lithium ion batteries – such as ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC) and the (50:50 wt%) mixture of EC:DMC was studied experimentally at pressures close to atmospheric and as a function of temperature between (280 and 343) K by using an isochoric saturation technique. The effect of the selected anions of a lithium salt LiX (X = hexafluorophosphate,

High-impedance metasurfaces with interwoven conductor patterns

High impedance metasurfaces (HIMSs) formed by interwoven conductor arrays are proposed. Bandwidth comparable with that of the basic square patches is achieved at an order of magnitude smaller unit cells. The presented structures are apt for small mobile terminals and low frequency applications.

Optical Spectroscopy of Unbound Asteroid Pairs

The recently discovered unbound asteroid pairs have been suggested to be the result of the decoupling of binary asteroids formed either through collision processes or, more likely, rotational fission of a rubble-pile asteroid after spin-up (Vokrouhlicky et al. 2008, AJ 136, 280; Pravec et al., 2010, Nature, 466, 1085). Much of the evidence for linkage of the asteroids in each pair relies solely on the backwards integrations of their orbits. We report new results from our continuing spectroscopic survey of the unbound asteroid pairs, including the youngest known pair, (6070) Rhineland - (54827) 2001 NQ8. The survey goal is to determine whether the asteroids in each unbound pair have similar spectra and therefore composition, expected if they have formed from a common parent body. Low-resolution spectroscopy covering the range 0.4-0.95 microns was conducted using the 3.6m ESO NTT+EFOSC2 during 2011-2012 and the 4.2m WHT+ACAM. We have attempted to maintain a high level of consistency between the observations of the components in each pair to ensure that differences in the asteroid spectra are not the result of the observing method or data reduction, but purely caused by compositional differences. Our WHT data indicates that the asteroids of unbound pair 17198 - 229056 exhibit different spectra and have been assigned different taxonomies, A and R respectively. Initial analysis of our data from the NTT suggests that the asteroids in unbound pairs 6070 - 54827 and 38707 - 32957 are likely silicate-dominated asteroids. The components of pair 23998 - 205383 are potentially X-type asteroids. We present final taxonomic classifications and the likelihood of spectral similarity in each pair.

Systematic Uncertainties Associated with the Cosmological Analysis of the First PAN-STARRS1 Type Ia Supernova Sample

We probe the systematic uncertainties from the 113 Type Ia supernovae (SN Ia) in the Pan-STARRS1 (PS1) sample along with 197 SN Ia from a combination of low-redshift surveys. The companion paper by Rest et al. describes the photometric measurements and cosmological inferences from the PS1 sample. The largest systematic uncertainty stems from the photometric calibration of the PS1 and low-z samples. We increase the sample of observed Calspec standards from 7 to 10 used to define the PS1 calibration system. The PS1 and SDSS-II calibration systems are compared and discrepancies up to ∼0.02 mag are recovered. We find uncertainties in the proper way to treat intrinsic colors and reddening produce differences in the recovered value of w up to 3%. We estimate masses of host galaxies of PS1 supernovae and detect an insignificant difference in distance residuals of the full sample of 0.037 ± 0.031 mag for host galaxies with high and low masses. Assuming flatness and including systematic uncertainties in our analysis of only SNe measurements, we find w = -1.120^+0.360_-0.206(Stat)^+0.269_-0.291(Sys). With additional constraints from Baryon acoustic oscillation, cosmic microwave background (CMB) (Planck) and H₀ measurements, we find w = -1.166^+0.072_-0.069 and Ω_m = 0.280^+0.013_-0.012 (statistical and systematic errors added in quadrature). The significance of the inconsistency with w = -1 depends on whether we use Planck or Wilkinson Microwave Anisotropy Probe measurements of the CMB: w_{BAO+H0+SN+WMAP} = -1.124^+0.083_-0.065.

Cosmological Constraints from Measurements of Type Ia Supernovae Discovered During the First 1.5 Yr of the Pan-STARRS1 Survey

We present griz_P1 light curves of 146 spectroscopically confirmed Type Ia supernovae (SNe Ia; 0.03 < z < 0.65) discovered during the first 1.5 yr of the Pan-STARRS1 Medium Deep Survey. The Pan-STARRS1 natural photometric system is determined by a combination of on-site measurements of the instrument response function and observations of spectrophotometric standard stars. We find that the systematic uncertainties in the photometric system are currently 1.2% without accounting for the uncertainty in the Hubble Space Telescope Calspec definition of the AB system. A Hubble diagram is constructed with a subset of 113 out of 146 SNe Ia that pass our light curve quality cuts. The cosmological fit to 310 SNe Ia (113 PS1 SNe Ia + 222 light curves from 197 low-z SNe Ia), using only supernovae (SNe) and assuming a constant dark energy equation of state and flatness, yields w = -1.120^+0.360_-0.206(Stat)^+0.269_0.291(Sys). When combined with BAO+CMB(Planck)+H₀, the analysis yields Ω_M = 0.280^+0.013_0.012 and w = -1.166^+0.072_-0.069 including all identified systematics. The value of w is inconsistent with the cosmological constant value of -1 at the 2.3σ level. Tension endures after removing either the baryon acoustic oscillation (BAO) or the H₀ constraint, though it is strongest when including the H₀ constraint. If we include WMAP9 cosmic microwave background (CMB) constraints instead of those from Planck, we find w = -1.124^+0.083_-0.065, which diminishes the discord to <2σ. We cannot conclude whether the tension with flat ΛCDM is a feature of dark energy, new physics, or a combination of chance and systematic errors. The full Pan-STARRS1 SN sample with ∼three times as many SNe should provide more conclusive results.

Periodate – an alternative oxidant for testing potential water oxidation catalysts

The redox catalyst ruthenium dioxide, prepared via the Adams technique, i.e.Ru(Adams), is used as a water oxidation catalyst using the oxidants (i) Ce(IV) in 0.5M H2SO4 and (ii) periodate in 0.5 M H2SO4, water and 0.1 M KOH. Like Ce(IV),periodate is a very strong oxidant that is able to oxidise water to oxygen and can bereadily monitored spectrophotometrically at 280 nm, compared with 430 nm for Ce(IV).More importantly, unlike Ce(IV), which is unstable towards hydrolysis above pH 1,periodate is stable in acid, water and strong alkali. A spectrophotometric study of thekinetics of periodate reduction, and concomitant oxidation of water to O2, reveals thatin the presence of a suitable redox catalyst, Ru(Adams) in this work, periodate is ableto effect the stoichiometric oxidation of water, with a turnover number > 64. In justwater, the kinetics of the latter reaction appear diffusion-controlled, due to the largethermodynamic driving force, a measure of which is the difference in redox potential,i.e. ∆E = 423 mV. As this difference is decreased, ∆E = 396 mV in acid and 290 mVin strong alkali (0.1 M KOH), the kinetics become increasingly activation-controlledand slower. These findings are discussed briefly with regard to the possible use of (i)periodate as an alternative oxidant in the rapid screening of new potential wateroxidation catalyst material powders that are stable only under near neutral and/oralkaline conditions, and (ii) Ru(Adams) as a benchmark catalyst.

The frequency of Environmental Quality Standard (EQS) exceedance for chlorinated organic pollutants in rivers of the Humber catchments

The southern industrial rivers (Aire, Calder, Don and Trent) feeding the Humber estuary were routinely monitored for a range of chlorinated micro- organic contaminants at least once a week over a 1.5-year period. Environmental Quality Standards (EQSs) for inland waters were set under the European Economic Community for a limited number of problematic contaminants (18). The results of the monitoring program for seven classes of chlorinated pollutants on the EQS list are presented in this study. All compounds were detected frequently with the exception of hexachlorobutadiene (where only one detectable measurement out of 280 individual samples occurred). In general, the rivers fell into two classes with respect to their contamination patterns. The Aire and Calder carried higher concentrations of micro- pollutants than the Don and Trent, with the exception of hexachlorobenzene (HCB). For Σ hexachlorocyclohexane (HCH) isomers (α + γ) and for dieldrin, a number of samples (~ 5%) exceeded their EQS for both the Aire and Calder. Often, ΣHCH concentrations were just below the EQS level. Levels of p,p'- DDT on occasions approached the EQS for these two rivers, but only one sample (out of 140) exceeded the EQS. No compounds exceeded their EQS levels on the Don and Trent. Analysis of the ratio of γ HCH/αHCH indicated that the source of HCH for the Don and Trent catchments was primarily lindane (γHCH) and, to a lesser extent, technical HCH (mixture of HCH isomers, dominated by α HCH), while the source(s) for the Aire and Calder had a much higher contribution from technical HCH.

Dengue Envelope Domain III-Peptide Binding Analysis via Tryptophan Fluorescence Quenching Assay

In the efforts to find an anti-viral treatment for dengue, a simple tryptophan fluorescence-screening assay aimed at identifying dengue domain III envelope (EIII) protein inhibitors was developed. Residue Trp391 of EIII was used as an intrinsic probe to monitor the change in fluorescence of the tryptophan residue upon binding to a peptide. The analysis was based on the electron excitation at 280 nm and fluorescence emission at 300–400 nm of EIII, followed by quenching of fluorescence in the presence of potential peptidic inhibitors coded DS36wt, DS36opt, DN58wt and DN58opt. The present study found that the fluorescence of the recombinant EIII was quenched following the binding of DS36opt, DN58wt and DN58opt ina concentration-dependent manner. Since the λmax for emission remained unchanged, the effect was not dueto a change in the environment of the tryptophan side chain. In contrast, a minimal fluorescence-quenching effect of DS36wt at 20 and 40 µM suggested that the DS36wt does not have any binding ability to EIII. This was supported by a simple native-page gel retardation assay that showed a band shift of EIII domain whenincubated with DS36opt, DN58wt and DN58opt but not with DS36wt. We thus developed a low-cost and convenientspectrophotometric binding assay for the analysis of EIII–peptide interactions in a drug screening application.