Strongly coupled chameleon fields: possible test with a neutron Lloyd's mirror interferometer

The consideration is presented of possible neutron Lloyd's mirror interferometer experiment to search for strongly coupled chameleon fields. The chameleon scalar fields were proposed to explain the early and late time acceleration of expansion of the Universe. They may produce short-range interaction between particles and matter. This interaction causes phase shift of neutron waves in the interferometer. Estimates of sensitivity are performed.Comment: 11 p, 3 fig; the title is changed, extended feasibility consideration: expected intensity and systematic effect

Bovine serum amine oxidase and chromate-modified iron oxide nanoparticles for polyamine biosensing

Surface active maghemite nanoparticles (SAMNs) represent a new class of naked maghemite nanoparticles, characterized by peculiar surface properties. A novel hybrid nanomaterial based on SAMNs was developed by coating nanoparticle surface with bichromate, leading to a SAMN@Cr2O7 core\u2013shell nanoconjugate. Electrochemical impedance spectroscopy, cyclic voltammetry, and chronoamperometry showed lower charge transfer resistances, higher capacitive currents, better electrochemical performances, as well as more reversible electrochemical behavior with respect to bare SAMNs. Bichromate shell enhanced SAMN electrocatalytic proper- ties toward hydrogen peroxide reduction at neutral pH. Furthermore, bovine serum amino oxidase (BSAO) was immobilized on the surface of SAMN@Cr2O7 by self-assembly, leading to a magnetic drivable nanocatalyst for polyamine oxidation (SAMN@Cr2O7-BSAO). The hybrid bio-nanomaterial was kinetically characterized and compared with the native enzyme. Immobilized BSAO showed a catalytic constant of about 10.2 % with respect to the native enzyme, while the Michaelis constant, Km , was about 3.7 times higher upon enzyme immobilization. Correspondingly, the binding process led to a 2.4 fold decrease of BSAO catalytic efficiency, kcat/Km. The immobilized enzyme (SAMN@Cr2O7-BSAO) was exploited, in a simple carbon paste electrode configuration, for the development of a new reagentless electrochemical biosensor for polyamines

A miniaturized radiation monitor for continuous dosimetry and particle identification in space

Abstract A Miniaturized Radiation Monitor (MIRAM) has been developed for the continuous measurement of the radiation field composition and ionizing dose rates in near earth orbits. Compared to currently used radiation monitors, the presented device has an order of magnitude lower weight while being comparable in power consumption and functionality. MIRAM is capable of on-board real-time self-diagnostic. Furthermore, it supports on-board analysis of the measured data to be able to work autonomously. The dose rate is calculated continuously based on the energy deposition in the Timepix3 detector. For the estimation of the particle species composition of the radiation environment, two methods are applied depending on the current flux. At lower fluxes (&lt;104 particles per cm2 per s), a track-by-track analysis based on temporal coincidence is applied. At higher fluxes, a less power and memory consuming method is utilized. This method is using the averaged deposited energy per pixel to estimate the electron and proton content of the radiation field.</jats:p

A miniaturized radiation monitor for continuous dosimetry and particle identification in space

A Miniaturized Radiation Monitor (MIRAM) has been developed for the continuous measurement of the radiation field composition and ionizing dose rates in near earth orbits. Compared to currently used radiation monitors, the presented device has an order of magnitude lower weight while being comparable in power consumption and functionality. MIRAM is capable of on-board real-time self-diagnostic. Furthermore, it supports on-board analysis of the measured data to be able to work autonomously. The dose rate is calculated continuously based on the energy deposition in the Timepix3 detector. For the estimation of the particle species composition of the radiation environment, two methods are applied depending on the current flux. At lower fluxes (<104 particles per cm2 per s), a track-by-track analysis based on temporal coincidence is applied. At higher fluxes, a less power and memory consuming method is utilized. This method is using the averaged deposited energy per pixel to estimate the electron and proton content of the radiation field.A Miniaturized Radiation Monitor (MIRAM) has been developed for the continuous measurement of the radiation field composition and ionizing dose rates in near earth orbits. Compared to currently used radiation monitors, the presented device has an order of magnitude lower weight while being comparable in power consumption and functionality. MIRAM is capable of on-board real-time self-diagnostic. Furthermore, it supports on-board analysis of the measured data to be able to work autonomously. The dose rate is calculated continuously based on the energy deposition in the Timepix3 detector. For the estimation of the particle species composition of the radiation environment, two methods are applied depending on the current flux. At lower fluxes (<104 particles per cm2 per s), a track-by-track analysis based on temporal coincidence is applied. At higher fluxes, a less power and memory consuming method is utilized. This method is using the averaged deposited energy per pixel to estimate the electron and proton content of the radiation field