Lightning current test on radar system

With the extended use of very sensitive electronic components, in modern systems, the danger represented by a lightning stroke becomes something not to be neglected. The Long Range Radar requires protection not only against direct strike, but also against the indirect effects. The formulation of the military standard MIL-STD-464A Severe Strike confirms this need. The peak currents of the discharges are between 50 and 200 kA, for the A pulse, 2 kA for the B pulse and 200 to 800 Amps for the C pulse. For a radar system placed high on a ship, the chosen approach is the fictitious Rolling Sphere Technique in order to confirm the protection offered by the design. Experiments have been carried out using a test setup that could duplicate the three discharge components

Observation of the spin Peltier effect

We report the observation of the spin Peltier effect (SPE) in the ferrimagnetic insulator Yttrium Iron Garnet (YIG), i.e. a heat current generated by a spin current flowing through a Platinum (Pt)|YIG interface. The effect can be explained by the spin torque that transforms the spin current in the Pt into a magnon current in the YIG. Via magnon-phonon interactions the magnetic fluctuations modulate the phonon temperature that is detected by a thermopile close to the interface. By finite-element modelling we verify the reciprocity between the spin Peltier and spin Seebeck effect. The observed strong coupling between thermal magnons and phonons in YIG is attractive for nanoscale cooling techniques.Comment: 5 pages, 3 figures, 4 pages supplementary information, 4 supplementary figure

Detection and control of individual nuclear spins using a weakly coupled electron spin

We experimentally isolate, characterize and coherently control up to six individual nuclear spins that are weakly coupled to an electron spin in diamond. Our method employs multi-pulse sequences on the electron spin that resonantly amplify the interaction with a selected nuclear spin and at the same time dynamically suppress decoherence caused by the rest of the spin bath. We are able to address nuclear spins with interaction strengths that are an order of magnitude smaller than the electron spin dephasing rate. Our results provide a route towards tomography with single-nuclear-spin sensitivity and greatly extend the number of available quantum bits for quantum information processing in diamond

A method for mechanical generation of radio frequency fields in nuclear magnetic resonance force microscopy

We present an innovative method for magnetic resonance force microscopy (MRFM) with ultra-low dissipation, by using the higher modes of the mechanical detector as radio frequency (rf) source. This method allows MRFM on samples without the need to be close to an rf source. Furthermore, since rf sources require currents that give dissipation, our method enables nuclear magnetic resonance experiments at ultra-low temperatures. Removing the need for an on-chip rf source is an important step towards a MRFM which can be widely used in condensed matter physics.Comment: 7 pages, 5 figures, to be submitted to Physical Review Applie

Thermoelectric Detection of Ferromagnetic Resonance of a Nanoscale Ferromagnet

We present thermoelectric measurements of the heat dissipated due to ferromagnetic resonance of a Permalloy strip. A microwave magnetic field, produced by an on-chip coplanar strip waveguide, is used to drive the magnetization precession. The generated heat is detected via Seebeck measurements on a thermocouple connected to the ferromagnet. The observed resonance peak shape is in agreement with the Landau-Lifshitz-Gilbert equation and is compared with thermoelectric finite-element modeling. Unlike other methods, this technique is not restricted to electrically conductive media and is therefore also applicable to for instance ferromagnetic insulators

Analytische methoden voor de bepaling van organische microverontreinigingen in grond en sediment

Deel 1 betreft: gechloreerde pesticiden, gechloreerde industriele contaminanten en polycyclische aromate

Eff ects of health-system strengthening on under-5, infant, and neonatal mortality: 11-year provincial-level time-series analyses in Mozambique

Background Knowledge of the relation between health-system factors and child mortality could help to inform health policy in low-income and middle-income countries. We aimed to quantify modifi able health-system factors and their relation with provincial-level heterogeneity in under-5, infant, and neonatal mortality over time in Mozambique. Methods Using Demographic and Health Survey (2003 and 2011) and Multiple Indicator Cluster Survey (2008) data, we generated provincial-level time-series of child mortality in under-5 (ages 0–4 years), infant (younger than 1 year), and neonatal (younger than 1 month) age groups for 2000–10. We built negative binomial mixed models to examine health-system factors associated with changes in child mortality. Findings Under-5 mortality rate was heterogeneous across provinces, with yearly decreases ranging from 11·1% (Nampula) to 1·9% (Maputo Province). Heterogeneity was greater for neonatal mortality rate, with only seven of 11 provinces showing signifi cant yearly decreases, ranging from 13·6% (Nampula) to 4·2% (Zambezia). Health workforce density (adjusted rate ratio 0·94, 95% CI 0∙90–0∙98) and maternal and child health nurse density (0∙96, 0∙92–0∙99) were both associated with reduced under-5 mortality rate, as were institutional birth coverage (0∙94, 0∙90–0∙98) and government fi nancing per head (0∙80, 0∙65–0∙98). Higher population per health facility was associated with increased under-5 mortality rate (1∙14, 1∙02–1∙28). Neonatal mortality rate was most strongly associated with institutional birth attendance, maternal and child nurse density, and overall health workforce density. Infant mortality rate was most strongly associated with institutional birth attendance and population per health facility. Interpretation The large decreases in child mortality seen in Mozambique between 2000 and 2010 could have been partly caused by improvements in the public-sector health workforce, institutional birth coverage, and government health fi nancing. Increased attention should be paid to service availability, because population per health facility is increasing across Mozambique and is associated with increased under-5 mortality. Investments in health information systems and new methods to track potentially increasing subnational health disparities are urgently needed

Bayesian Data-Driven approach enhances synthetic flood loss models

Flood loss estimation models are developed using synthetic or empirical approaches. The synthetic approach consists of what-if scenarios developed by experts. The empirical models are based on statistical analysis of empirical loss data. In this study, we propose a novel Bayesian Data-Driven approach to enhance established synthetic models using available empirical data from recorded events. For five case studies in Western Europe, the resulting Bayesian Data-Driven Synthetic (BDDS) model enhances synthetic model predictions by reducing the prediction errors and quantifying the uncertainty and reliability of loss predictions for post-event scenarios and future events. The performance of the BDDS model for a potential future event is improved by integration of empirical data once a new flood event affects the region. The BDDS model, therefore, has high potential for combining established synthetic models with local empirical loss data to provide accurate and reliable flood loss predictions for quantifying future risk