Radiative lepton flavor violating decays in the Randall Sundrum background with localized leptons

We study the radiative lepton flavor violating l_i -> l_j\gamma decays in the two Higgs doublet model, respecting the Randall Sundrum scenario and estimate the contributions of the KK modes of left (right) handed charged lepton doublets (singlets) on the branching ratios. We observe that the branching ratios are sensitive to the contributions of the charged lepton KK modes.Comment: 23 pages, 10 figures, 2 table

Atmospheric Pressure Non-thermal Plasma for Air Purification: Ions and Ionic Reactions Induced by dc+ Corona Discharges in Air Contaminated with Acetone and Methanol

Atmospheric pressure mass spectrometry (APCI-MS) was used to investigate the positive ions in air containing acetone (A), methanol (M) and mixtures thereof (A + M), subjected to +dc corona discharges. The results of experiments with isotopically labelled analogues, perdeuterated acetone Adeu and methanol Mdeu, and relevant thermochemical data found in the literature allowed us to identify the main ionic reactions occurring in single component systems (A or M) and in binary mixtures (A + M). It is concluded that, thanks to its significantly higher proton affinity, A is very efficient in quenching M-derived ions at atmospheric pressure. These conclusions provide a rationale for interpreting the results of a parallel investigation on the reciprocal effects of M and A when treated together in air at atmospheric pressure with +dc corona in a non-thermal plasma reactor developed previously in our laboratory. Specifically, we observed a marked drop in the degradation efficiency of methanol when it was treated in the presence of an equivalent amount of acetone. This effect is attributed to acetone interfering with ion-initiated degradation processes of methanol, and supports the conclusion\ua0that ions and ionic reactions are important in dc+ corona induced oxidation of volatile organic pollutants in air

Efficiency, products and mechanisms of ethyl acetate oxidative degradation in air non-thermal plasma

Ethyl acetate (EA) is a popular solvent and diluent in many products and one of the most ubiquitous organic pollutants of indoor air. Although EA's ascertained toxicity is classified as low, exposure to its vapors at concentrations 400 ppm causes serious problems in humans. EA is thus a frequent target in testing novel technologies for air purification. We report here an investigation of EA oxidative degradation in air at room temperature and atmospheric pressure induced by corona discharges. Three corona regimes, dc-, dc+ and pulsed +, were tested in the same reactor under various experimental conditions with regard to EA initial concentration (C 0) and the presence of humidity in the system. The EA degradation process was monitored by gas chromatography (GC)-flame ionization detection, GC-mass spectrometry and Fourier transform infrared spectroscopy analysis of the treated gas. These analyses yielded the concentration of residual EA (C) and those of its major products of oxidation (CO2, CO) and revealed a few organic reaction intermediates formed along the oxidation chain. The process energy efficiency was determined as energy constant, k E (kJ-1 l) and as energy yield, EY (g kW-1 h-1). The efficiency depends on the type of corona (pulsed + >dc- >dc+), on the presence of humidity in the air (improvement in the case of dc-, little or no effect for dc+) and on C 0 (k E increases linearly with 1/C 0). CO2 and CO were the major carbon containing products, confirming the strong oxidizing power of air non-thermal plasma. Acetic acid and acetaldehyde were detected in very small amounts as reaction intermediates. The experimental results obtained in this work support the conclusion that different reactive species are involved in the initial step of EA oxidation in the case of dc- and dc+ corona air non-thermal plasma

Search for Tau Flavour Violation at the LHC

We explore the prospects for searches at the LHC for sparticle decays that violate $\tau$ lepton number, in the light of neutrino oscillation data and the seesaw model for neutrino masses and mixing. We analyse the theoretical and phenomenological conditions required for tau flavour violation to be observable in \chi_2 \to \chi + \tau^\pm \mu^\mp decays, for cosmologically interesting values of the relic neutralino LSP density. We study the relevant supersymmetric parameter space in the context of the Constrained Minimal Supersymmetric Extension of the Standard Model (CMSSM) and in SU(5) extensions of the theory. We pay particular attention to the possible signals from hadronic tau decays, that we analyse using PYTHIA event simulation. We find that a signal for \tau flavour-violating \chi_2 decays may be observable if the branching ratio exceeds about 10%. This may be compatible with the existing upper limit on \tau \to \mu \gamma decays if there is mixing between right-handed sleptons, as could be induced in non-minimal SU(5) GUTs.Comment: 24 pages, 10 fig

Comment on "water-Soluble Fluorescent Probe with Dual Mitochondria/Lysosome Targetability for Selective Superoxide Detection in Live Cells and in Zebrafish Embryos"

Recently, a new water-soluble, fluorescein-based probe for the detection of superoxide radical anion in aqueous media was developed by Lu et al. (ACS Sens. 2018, 3, 59-64). The probe was proven to be selective for superoxide and was used successfully also in cells and zebrafish embryos. To characterize the response of the probe to superoxide, Lu et al. used KO2 dissolved in deionized water as a surrogate. In testing this probe in different applications, we repeated some of these experiments and came to realize that the fluorescence signal observed by the Authors in their experiments with KO2 was incorrectly attributed to the reaction of the probe with superoxide and is due instead to its reactions with HO- and HO2-. We show that indeed under the conditions used in these assays KO2 undergoes very fast reaction with water to form HO- and HO2-. On the other hand, by using a proper surrogate, namely, KO2 dissolved in DMSO, and spin trapping experiments, we confirmed the ability of the probe to detect superoxide

Antisymmetric tensor unparticle and the radiative lepton flavor violating decays

We study the contribution of the tensor unparticle mediation to the branching ratios of the radiative lepton flavor violating decays and predict a restriction region for free parameters of the scenario by using experimental upper limits. We observe that the branching ratios of the radiative lepton flavor violating decays are sensitive to the fundamental mass scales of the scenario and to the scale dimension of antisymmetric tensor unparticle. We obtain a more restricted set for the free parameters in the case of the \mu\rightarrow e \gamma decayComment: 15 pages, 10 figure

Use of Foundry Sands in the Production of Ceramic and Geopolymers for Sustainable Construction Materials

The aim of this research was to evaluate the possibility of reusing waste foundry sands derived from the production of cast iron as a secondary raw material for the production of building materials obtained both by high-temperature (ceramic tiles and bricks) and room-temperature (binders such as geopolymers) consolidation. This approach can reduce the current demand for quarry sand and/or aluminosilicate precursors from the construction materials industries. Samples for porcelain stoneware and bricks were produced, replacing the standard sand contained in the mixtures with waste foundry sand in percentages of 10%, 50%, and 100% by weight. For geopolymers, the sand was used as a substitution for metakaolin (30, 50, 70 wt%) as an aluminosilicate precursor rather than as an aggregate to obtain geopolymer pastes. Ceramic samples obtained using waste foundry sand were characterized by tests for linear shrinkage, water absorption, and colorimetry. Geopolymers formulations, produced with a Si/Al ratio of 1.8 and Na/Al = 1, were characterized to evaluate their chemical stability through measurements of pH and ionic conductivity, integrity in water, compressive strength, and microstructural analysis. The results show that the addition of foundry sand up to 50% did not significantly affect the chemical-physical properties of the ceramic materials. However, for geopolymers, acceptable levels of chemical stability and mechanical strength were only achieved when using samples made with 30% foundry sand as a replacement for metakaolin

A FAST MODEL FOR FLOW AND POLLUTANT DISPERSION AT THE NEIGHBOURHOOD SCALE

This paper deals with the development of a simple urban model for flow and dispersion in the urban canopy layer (UCL). The flow module of the model calculates spatially-averaged wind profiles adopting a technique recently proposed in the literature, which is based on a balance equation between the obstacle drag force and the local shear stress. Spatially-averaged wind profiles are used as input for a newly proposed dispersion model which solves the advection-diffusion equation at neighbourhood scale. In the model, the effects of the buildings within the UCL are taken into account by means of morphological parameters λf and λp (the ratios of plan area and frontal area of buildings to the lot area). Spatially-averaged mean concentrations output by the developed model are compared with numerical results obtained from the computational fluid dynamics (CFD) model FLUENT. In particular, two configurations of constant height UCL have been considered, which refer to as λp = λf = 0.16 and λp = λf = 0.44. The originality of the study is that the dispersion model itself integrates the equations without explicitly resolving the flow around individual buildings but still accounts for their effects. The computational costs are much reduced which makes it suitable for the predictions of concentrations over the neighbourhood scale in an operational context

Waiting for mu->eg from the MEG experiment

The Standard Model (SM) predictions for the lepton flavor-violating (LFV) processes like mu->eg are well far from any realistic experimental resolution, thus, the appearance of m->eg at the running MEG experiment would unambiguously point towards a New Physics (NP) signal. In this article, we discuss the phenomenological implications in case of observation/improved upper bound on m->eg at the running MEG experiment for supersymmetric (SUSY) scenarios with a see-saw mechanism accounting for the neutrino masses. We outline the role of related observables to m->eg in shedding light on the nature of the SUSY LFV sources providing useful tools i) to reconstruct some fundamental parameters of the neutrino physics and ii) to test whether an underlying SUSY Grand Unified Theory (GUT) is at work. The perspectives for the detection of LFV signals in tau decays are also discussed.Comment: 15 pages, 12 figure