Gibanje iona u alkalnim halidima s primjesnim defektima i seljenje centara boje toplinskim bijeljenjem

Measurements of ionic conductivity in pure alkali halides and in alkali halides with doping-induced defects were made to determine the activation energies and mobility of F-centres. The activation energies in NaCl:Cd+2 were found large in comparison with NaCl with other divalent impurities. The mobilities of F-centre migration on bleaching of injected electrons were measured and the activation energies of bleaching WF have been found. The results for space-charge-limited conduction of F-centres are explained with the determined values of activation energies W and WF.Načinili smo mjerenja ionske vodljivosti u čistim alkalnim halidima i u alkalnim halidima s primjesnim defektima radi određivanja aktivacijskih energija i pokretljivosti F-centara. U NaCl:Cd+2 našli smo velike vrijednosti aktivacijske energije u odnosu na NaCl s drugim divalentnim nečistoćama. Mjerili smo pokretljivost F-centara pri bijeljenju i odredili aktivacijske energije bijeljenja WF . Ishodi mjerenja za vodljivost F-centara ograničenu prostornim nabojem objašnjavaju se vrijednostima određenih aktivacijskih energija W i WF

Supernova neutrino induced neutrons in liquid xenon dark matter detectors

Neutrinos from supernova (SN) bursts can give rise to detectable number of nuclear recoil (NR) events through the process of coherent elastic neutrino-nucleus scattering (CE$\nu$NS) in future large (multi-ton scale) liquid xenon detectors employed for dark matter search depending on the SN progenitor mass and distance to the SN event. Here we point out that in addition to the direct NR events due to CE$\nu$NS process, there is a secondary source of nuclear recoils due to elastic scattering of the neutrons produced through inelastic neutrino-nucleus scattering of the supernova neutrinos with the target xenon nuclei. We estimate the contribution of these supernova neutrino-induced neutrons ($\nu$In) to the total xenon NR spectrum and find that the latter can be significantly modified at large recoil energies from that expected from the CE$\nu$NS process alone, with the $\nu$In contribution dominating the total integral recoil energy spectrum at recoil energies above $\sim$20 keV. With the capability to measure the energies of individual recoil events, sufficiently large liquid xenon detectors may be able to detect these events due to $\nu$In process triggered by neutrinos from reasonably close by SN burst events. We also note that the $\nu$In contribution to the recoil spectrum receives dominant contribution from the charged current interaction of the SN $\nu_e$s with the target nuclei while the CE$\nu$NS contribution comes from neutral current interactions of all the six species of neutrinos with the target nuclei. This may offer the possibility of extracting useful information about the distribution of the total SN explosion energy going into different neutrino flavors.Comment: Replaced with revised version; includes results of GEANT4 simulation of neutron induced xenon nuclear recoils; one additional author (SG); figures modified; 2 new figures; main conclusions remain unchanged; latex 9 pages with 6 figure

Elektroliza kroz homogene i nehomogene spojeve izolatora

The basic measurement of the primary state of ionization related to the formation of a non-rectifying contact by the electrolysis of insulating solids under homogeneous and heterogeneous contacts has been carried out. The activation energy involved in the first stage has been found to correlate with the band scheme of energy of contact which is necessary for creating the defect centres towards space charge limited injection.Načinili smo osnovna mjerenja početnog stanja ionizacije pri uspostavljanju neispravljačkog spoja nastalog elektrolizom na dodiru istorodnih ili neistorodnih izolatora. Našli smo da je prvotna aktivacijska energija vezana sa shemom pojaseva energijskih vrpci spoja koji su potrebni za stvaranje defektnih središta blizu ograničene injekcije prostornog naboja

Kinetička svojstva F-centara pod utjecajem topline

The migration of colour clouds after the electron injection in pure and doped KCl and KBr alkali halides under thermal and field stresses is studied with an anode contact of spherical geometry. The diffusion coefficient of the colour clouds has been obtained using a derived analytical expression and the experimental data, and the activation energy of the colour centre was estimated. The dissociation energy values under thermal and field stresses for doped crystals are deduced through the mobility transport equation. The results indicate the effect of doping in an otherwise pure counterpart of the same crystals.Proučavamo premještanje oblaka boje nakon ubacivanja elektrona u čiste i punjene kristale alkalnih halida KCl i KBr, pod djelovanjem topline i električnog polja, uz primjenu kuglaste elektrode. Pomoću izvedene analitičke relacije i mjernih podataka odredili smo koeficijent difuzije oblaka boje i ocijenili aktivacijsku energiju centara boje. Primjenom jednadžbe pokretljivosti izveli smo vrijednosti disocijacijske energije pod toplinskim i električnim naprezanjem za punjene kristale. Podaci pokazuju učinak punjenja u odnosu na čiste kristale

Internalization of Staphylococcus aureus in Lymphocytes Induces Oxidative Stress and DNA Fragmentation: Possible Ameliorative Role of Nanoconjugated Vancomycin

Staphylococcus aureus is the most frequently isolated pathogen causing bloodstream infections, skin and soft tissue infections and pneumonia. Lymphocyte is an important immune cell. The aim of the present paper was to test the ameliorative role of nanoconjugated vancomycin against Vancomycin-sensitive Staphylococcus aureus (VSSA) and vancomycin-resistant Staphylococcus aureus (VRSA) infection-induced oxidative stress in lymphocytes. VSSA and VRSA infections were developed in Swiss mice by intraperitoneal injection of 5 × 106 CFU/mL bacterial solutions. Nanoconjugated vancomycin was adminstrated to VSSA- and VRSA-infected mice at its effective dose for 10 days. Vancomycin was adminstrated to VSSA- and VRSA-infected mice at a similar dose, respectively, for 10 days. Vancomycin and nanoconjugated vancomycin were adminstrated to normal mice at their effective doses for 10 days. The result of this study reveals that in vivo VSSA and VRSA infection significantly increases the level of lipid peroxidation, protein oxidation, oxidized glutathione level, nitrite generation, nitrite release, and DNA damage and decreases the level of reduced glutathione, antioxidant enzyme status, and glutathione-dependent enzymes as compared to control group, which were increased or decreased significantly near to normal in nanoconjugated vancomycin-treated group. These findings suggest the potential use and beneficial role of nanoconjugated vancomycin against VSSA and VRSA infection-induced oxidative stress in lymphocytes

Physics Potential of the ICAL detector at the India-based Neutrino Observatory (INO)

The upcoming 50 kt magnetized iron calorimeter (ICAL) detector at the India-based Neutrino Observatory (INO) is designed to study the atmospheric neutrinos and antineutrinos separately over a wide range of energies and path lengths. The primary focus of this experiment is to explore the Earth matter effects by observing the energy and zenith angle dependence of the atmospheric neutrinos in the multi-GeV range. This study will be crucial to address some of the outstanding issues in neutrino oscillation physics, including the fundamental issue of neutrino mass hierarchy. In this document, we present the physics potential of the detector as obtained from realistic detector simulations. We describe the simulation framework, the neutrino interactions in the detector, and the expected response of the detector to particles traversing it. The ICAL detector can determine the energy and direction of the muons to a high precision, and in addition, its sensitivity to multi-GeV hadrons increases its physics reach substantially. Its charge identification capability, and hence its ability to distinguish neutrinos from antineutrinos, makes it an efficient detector for determining the neutrino mass hierarchy. In this report, we outline the analyses carried out for the determination of neutrino mass hierarchy and precision measurements of atmospheric neutrino mixing parameters at ICAL, and give the expected physics reach of the detector with 10 years of runtime. We also explore the potential of ICAL for probing new physics scenarios like CPT violation and the presence of magnetic monopoles.Comment: 139 pages, Physics White Paper of the ICAL (INO) Collaboration, Contents identical with the version published in Pramana - J. Physic