4 research outputs found

    Magnetic and magneto-optical properties of films of multiferroic GdMnO3 grown on LSAT [(LaAlO3)0.3 (Sr2AlTaO6)0.7] (100) and (111)

    Get PDF
    The magnetic properties of multiferroic GdMnO 3 depend on strain which is produced in a thin film by growing an epitaxial film on a suitable substrate. We report an investigation of the magnetic and optical properties of GdMnO 3 , as a function of strain, produced by growing epitaxial films on the substrates on (LaAlO 3 ) 0.3 (Sr 2 AlTaO 6 ) 0.7 (LSAT) (100) and (111). Magnetic measurements have shown that at 5 K the easy direction of the film is in-plane for LSAT (100) and the canted moment is significantly smaller than the value found in bulk material but larger than that found for GdMnO 3 on SrTiO 3 (100). The coercive field of the GdMnO 3 /LSAT (100) has also been found to be smaller than for bulk single crystal samples but comparable to a thinner film of GdMnO 3 grown on SrTiO 3 . The magnetic properties of the film grown on LSAT (111) are very different. The transition to the canted phase is less pronounced and there is no magnetic hysteresis at low temperatures. The susceptibility data are fitted with the Curie's law and the measured magnetic moments for the film on LSAT (100) were similar to bulk values but significantly different for films on LSAT (111) and SrTiO 3 (100). The magnetic circular dichroism spectroscopy showed two features: the charge transfer transition between Mn d states at ~ 2 eV and the band edge transition from the oxygen p band to the d states at ~ 3 eV. Magnetic circular dichroism also shows that the transition at around 2 eV is stronger in LSAT (100) than in LSAT (111) implying that the structure of the film of GdMnO 3 is closer to that of LaMnO 3 when grown on LSAT (100)

    Bystander cardiopulmonary resuscitation for paediatric out-of-hospital cardiac arrest in England: an observational registry cohort study.

    Get PDF
    INTRODUCTION Bystander cardiopulmonary resuscitation (BCPR) is strongly advocated by resuscitation councils for paediatric out-of-hospital cardiac arrests (OHCAs). However, there are limited reports on rates of BCPR in children and its relationship with return of spontaneous circulation (ROSC) or survival outcomes. OBJECTIVE We describe the rate of BCPR and its association with any ROSC and survival- to- hospital-discharge. METHODS We conducted retrospective analysis of prospectively collected paediatric (<18 years of age) OHCA cases in England; we included specialist registry patients treated by emergency medical services (EMS) with known BCPR status and outcome between January 2014 and November 2018. Data included patient demographics, aetiology, witness status, initial rhythm, EMS, season, time of day and bystander status. Associations between BCPR, and any ROSC and survival-to-hospital-discharge outcomes were explored using multivariable logistic regression. RESULTS There were 2363 paediatric OHCAs treated across 11 EMS regions. BCPR was performed in 69.6% (1646/2363) of the cases overall (range 57.7% (206/367) to 83.7% (139/166) across EMS regions). Only 34.9% (550/1572) of BCPR cases were witnessed. Overall, any ROSC was achieved in 22.8% (523/2289) and survival to hospital discharge in 10.8% (225/2066). Adjusted odds ratio (aOR) for any ROSC was significantly improved following BCPR compared to no BCPR (aOR 1.37, 95% CI 1.03-1.81), but adjusted odds ratio for survival-to-hospital-discharge were similar (aOR 1.01, 95% CI 0.66-1.55). CONCLUSIONS BCPR was associated with improved rates of any ROSC but not survival-to-hospital-discharge. Variations in EMS BCPR rates may indicate opportunities for regional targeted increase in public BCPR education

    Synergistic flame retardancy and electrical conductivity in di-glycidyl ether of bisphenol-A epoxy composites with polyaniline and aluminum Tri-hydroxide

    No full text
    This study focuses on developing and characterizing multifunctional composites based on the diglycidyl ether of bisphenol-A (DGEBA) epoxy matrix. The aim is to enhance fire resistance and electrical conductivity properties for applications in various fields. To achieve this, aluminum tri-hydroxide (ATH) was incorporated as a flame retardant (FR) agent, while polyaniline (PANI) was added to impart electrical conductivity. The composites were categorized into three groups: the first containing flame retardant (FR), the second containing PANI for conductivity, and the third containing both PANI and FR for combined effects. E 60-FP emerged as the optimal multifunctional composite, exhibiting superior mechanical properties among the tested formulations. Thermogravimetric analysis (TGA) results provided valuable insights into the thermal stability of E 60-FP, revealing that it retained 42% of its initial mass at a temperature of 600 °C. Additionally, the composite achieved a V-0 rating in the UL 94 test, confirming its excellent fire resistance. Notably, E 60-FP displayed impressive mechanical strength, with a tensile strength of 7.2 MPa and a tensile modulus of 1117.6 MPa. Its flexural strength and modulus were measured at 31.2 MPa and 2800.2 MPa, respectively. Furthermore, the composite E 60-FP exhibited remarkable electrical conductivity, measuring 6.1 × 10 ^–6 S cm ^−1 . These findings highlight the potential of DGEBA epoxy composites containing PANI and ATH as promising materials for applications requiring fire resistance and electrical conductivity properties
    corecore