Ferroelectricity in the xAg2Nb4O11–(1−x)Na2Nb4O11 solid solution

Compositions in the (AgxNa1-x)2Nb4O11 solid solution have been prepared by a conventional solid state method. Composites containing Ag2Nb4O11 have been shown to be ferroelectric and the Curie temperature shown to decrease from 149 °C at x = 1 to 62 °C at x = 0.7. Roomtemperature compositions with x ≤ 0.7 are monoclinic, while those with x ≥ 0.8 are rhombohedral with structures consistent with the relevant end-members. At x = 0.75, the structure was mainly rhombohedral but with coexistence of the monoclinic structure, indicating the proximity of a phase boundary

HRXRD study of the theoretical densities of novel reactive sintered boride candidate neutron shielding materials

Reactive Sintered Borides (RSBs) are novel borocarbide materials derived from FeCr-based cemented tungsten (FeCr-cWCs) show considerable promise as compact radiation armour for proposed spherical tokamak,[1],[2],[3],[4],[5]. Six candidate compositions (four RSBs, two cWCs) were evaluated by high-resolution X-ray diffraction (XRD), inductively coupled plasma (ICP), energy dispersive X-ray analysis (EDX) and scanning electron microscopy (SEM) to determine the atomic composition, phase presence, and theoretical density. RSB compositions were evaluated with initial boron contents equivalent to 25 at% 30 at%. All RSB compositions showed delamination and carbon enrichment in the bulk relative to the surface, consistent with non-optimal binder removal and insufficient sintering time. Phase abundance within RSBs derived from powder XRD was dominated by iron tungsten borides (FeWB/FeW2B2), tungsten borides (W2B5/WB) and iron borides. The most optimal RSB composition (B5T522W) with respect to physical properties and highest ρ/ρtheo had ρtheo = 12.59 ± 0.01 g cm-3 for ρ/ρtheo = 99.3% and had the weigh-in and post-sintered W : B : Fe abundance closest to 1 : 1 : 1. This work indicates that despite their novelty, RSB materials can be optimized and in principle be processed using existing cWC processing routes

Victimhood & Agency: How Taking Charge Takes Its Toll

This Article addresses an unexplored tension in the civil justice system regarding victims. The goal of the civil system is to make victims whole. We can, as is most common, attempt to do this financially, or we can consider psychological research that suggests there may be other ways of restoring victims’ statuses. One of the most common nonfinancial solutions is to increase victim participation in the justice process. This is a solution that appeals to many victims and may benefit them psychologically. However, by increasing their participation, they may unknowingly trade off some of the benefits of victimhood. For instance, they may be awarded less financial compensation and may even be blamed more for their own victimization. Part II of this Article discusses financial and nonfinancial strategies for making victims whole in the civil justice system. Part III addresses the paradoxical nature of victimhood in this system, and Part IV suggests that the psychological construct of agency may shed light on the issues victims face. Part V presents three empirical studies suggesting there are unanticipated consequences for victims who play an active role in the justice process, which may have serious ramifications for their recovery. The Article concludes with a discussion of the policy implications of these results, the limitations of the current studies, and future directions for this line of research

Structures of K0.05Na0.95NbO3 (50–300 K) and K0.30Na0.70NbO3 (100–200 K)

Rietveld refinement using neutron powder diffraction data is reported for the potential lead-free piezoelectric material KxNa1 - xNbO3 (x = 0.05, x = 0.3) at low temperatures. The structures were determined to be of rhombohedral symmetry, space group R3c, with the tilt system a-a-a- for both compositions. It was found that some of the structural parameters differ significantly in the two structures, and particularly the NbO6 octahedral strains as a function of temperature. The 300 K profile for K0.05Na0.95NbO3 shows the coexistence of rhombohedral and monoclinic phases, which indicates that the phase boundary is close to room temperature; the phase boundary for K0.30Na0.70NbO3 is found to be at approximately 180 K

Disability Awareness Course Outline using the Torrence Incubation Model (TIM)

Developing an Undergraduate Course Outline on Disability Awareness This project guides the reader through the process of creating an undergraduate course exploring disability history and the need for inclusion in society. The Torrance Incubation Model (TIM) was used to create the course outline which includes the course description, outcomes, competencies, assessment of student learning, and a topical outline. This project is twofold, and may be used as a stepping stones for training Direct Support Professionals by intertwining New York State’s Core Competencies within the course content and objectives

Partial Hamiltonian reduction of relativistic extended objects in light-cone gauge

The elimination of the non-transversal field in the standard light-cone formulation of higher-dimensional extended objects is formulated as a Hamiltonian reduction.Comment: 11 page

Inference of oxygen vacancies in hydrothermal Na0.5Bi0.5TiO3

A high-resolution x-ray powder diffraction study has been made of pseudo-rhombohedral and tetragonal phases in Na0.5Bi0.5TiO3 (NBT), produced via hydrothermal and conventional solidstate methods. Hydrothermal NBT exhibits significantly greater structural distortion at room temperature than solid-state NBT. Peak widths and superstructure peak intensities show a phase transition at 305 C, with trends suggesting that the structure tends towards cubic symmetry at this temperature. Structural refinements indicate that the transition occurs via a phase coexistence region with no clear intermediate phase. Piezoelectric data show evidence of polarisation pinning in hydrothermal NBT, interpreted as a high proportion of oxygen vacancies

Bifurcated polarization rotation in bismuth-based piezoelectrics

ABO3 perovskite-type solid solutions display a large variety of structural and physical properties, which can be tuned by chemical composition or external parameters such as temperature, pressure, strain, electric, or magnetic fields. Some solid solutions show remarkably enhanced physical properties including colossal magnetoresistance or giant piezoelectricity. It has been recognized that structural distortions, competing on the local level, are key to understanding and tuning these remarkable properties, yet, it remains a challenge to experimentally observe such local structural details. Here, from neutron pair-distribution analysis, a temperature-dependent 3D atomic-level model of the lead-free piezoelectric perovskite Na0.5Bi0.5TiO3 (NBT) is reported. The statistical analysis of this model shows how local distortions compete, how this competition develops with temperature, and, in particular, how different polar displacements of Bi3+ cations coexist as a bifurcated polarization, highlighting the interest of Bi-based materials in the search for new lead-free piezoelectrics

First detection of intestinal microsporidia in Northern Nigeria

Microsporidia are intracellular spore-forming protozoa that are increasingly being recognized as pathogens in humans. Faecal samples were taken from 2250 HIV/AIDS and 1050 HIV-negative patients from Kano and Makurdi in Northern Nigeria, and were investigated for microsporidial infections by Giemsa staining technique (Light microscopy). In Kano, Enterocytozoon bienuesi was detected in 8 (14.17%) and Encephalitozoon intestinalis in 5 (2.60%) out of 192 HIV/AIDS patients screened. A mixed infection of both 0.52% was observed. Results from Makurdi showed that Enterocytozoon bienuesi was detected in 13 (0.65%) and Encephalitozoon intestinalis in 96 (4.78%) out of 2008 HIV/AIDS patients examined. No mixed infection was observed. Microsporidial spores were not found in 1050 HIV-negative patients screened from both areas. There was a significant difference (X2, p<0.05) in infection rates between the HIV/AIDS and HIV-negative patients. This study aimed at detecting the prevalence of intestinal microsporidia to provide baseline data on the status of this disease in Nigeria. Detection of Microsporidia in Immuno-compromised patients has not been described previously in this area

Analysis of Deprivations Suffered by Children Under Five in Benin

Children are seriously affected by poverty and suffer particular deprivations. In addition, their situation is most of the time ignored in the strategies devoted to tackling poverty. This study examined the multidimensional poverty of children under five in Benin by identifying its determinants. It used the data from the demographic and health surveys in Benin from 2011-2012 and adopted the approach by Alkire & Foster (2011) to generate multidimensional poverty profiles of children. The weightings of the dimensions were generated by multiple correspondence analysis. The GLM and Logit models were used to identify the driving factors of child deprivation. Findings indicate that 54 percent of children were multidimensionally poor when the poverty line k = 1 against 32 percent of poor children when k = 3.  Nutrition and sanitation dimensions had the highest relative contributions of 41.12 and 28.77 percent respectively to the global multidimensional poverty index. JEL Classification:  D63, I32, O1