Inhibition de la corrosion d'un acier au carbone par le Kemazur 1620

Dans cette étude, des mesures électrochimiques ont été utilisées pour caractériser l'efficacité inhibitrice du produit commercial Kemazur 1620, employé pour le traitement des eaux des circuits de refroidissement. L'influence de la concentration de ce composé ainsi que l'effet de la température du milieu ont été étudiés.Les courbes de polarisation ont été obtenues à l'aide d'un montage à trois électrodes. La méthode électrochimique a permis de déterminer la vitesse de corrosion en l'absence et en présence d'inhibiteur et par conséquent, le taux de protection. Ainsi, le Kemazur 1620 présente une très bonne efficacité pour une concentration de 2000 ppm. Entre 1000 et 2000 ppm, l'efficacité inhibitrice augmente de 56 à 91 %. En outre, l'efficacité inhibitrice du composé a été comparée à celle du nitrite de sodium.In this study, electrochemical measurements were carried out to characterize the inhibition efficiency of the commercial product Kemazur 1620, employed for water treatment in cooling circuits. The influence of parameters such as the concentration of the compound and the effect of the temperature on the behavior of the carbon steel / corrosion medium interface was studied. Polarization curves have been obtained by a three-electrode device. In the first part of this study, only the evolution of the corrosion rate as a function of concentration was examined. It has been shown from the polarization curves that the Kemazur 1620 presents a very good efficiency for a concentration of 2000 ppm. Between 1000 and 2000 ppm, the inhibition efficiency increases from 56 to 91 %. In a second part, the inhibition efficiency of the compound has been compared to an inhibitor used for similar uses

Degradation of AB25 dye in liquid medium by atmospheric pressure non-thermal plasma and plasma combination with photocatalyst TiO2

In this work, degradation of the anthraquinonic dye Acid Blue 25 by non-thermal plasma at atmospheric pressure with and without photocatalyst is investigated. Titanium dioxide (TiO2) is used as a photocatalyst. The dye degradation by plasma in the presence of TiO2 is investigated as a function of TiO2 concentration, dye concentration and pH. The degradation rate is higher in acidic solutions with pH of 2 to 4.3, especially at pH 2, and decreases to 0.38 mg L-1 min(-1) with the increase of pH from 2 to 5.65. A similar effect is observed in basic media, where a higher degradation rate is found at pH = 10.3. The degradation rate increases in the presence of TiO2 compared to the discharge without photocatalysis. The results show that the degradation of the dye increases in the presence of TiO2 until the catalyst load reaches 0.5 g L-1 after which the suppression of AB25 degradation is observed. The results indicate that the tested advanced oxidation processes are very effective for the degradation of AB25 in aqueous solutions

Salt effect on physiological, biochemical and anatomical structures of two Origanum majorana varieties (Tunisian and Canadian)

In this study, we evaluated the salt concentration effect on plant growth, mineral composition, antioxidant responses and anatomical structure of two varieties of Origanum majorana after exposure to NaCl treatment. Our results show an inclusive behaviour of the two varieties, since the majority of sodium was exported and accumulated in their aerial parts. The Canadian variety (CV) appeared relatively more tolerant to salt than the Tunisian one (TV). Transversal section of leaves showed a thickening of dorsal and ventral cuticle, more importantly in CV than in TV, in the presence and in absence of salt. This was accompanied by an increase in the length of palisade cells, and the width of spongy collenchyma lacuna. The stem had a subquadrangular shape in TV and quadrangular in the Canadian variety. At mature stage, the stem pit was reabsorbed in the TV and replaced by a large cavity, whereas it remained unchanged in CV. The relative salt tolerance of the CV was related to: (1) a good selectivity in favour of K+: (2) a strong peroxidase activity and (3) an increase in the lengthening of palisade cell accompanied with an increase of lacunae in spongy parenchyma in CV.Key words: Origanum majorana, salinity, growth, mineral nutrition, leaves, stems, anatomical, antioxidant

Chemical auxiliaries free dyeing of cationized cotton with 1:2 metal complex dye

Application of 1:2 metal complex dyes on pre-cationized cotton has been studied. This unconventional process avoids the use of electrolyte required as exhausting agent in conventional dyeing of cotton fabric. Indeed, when we use a large amount of salt, the discharged wastewater from dye house creates unavoidable environmental threats. The dyeing has been carried out at the liquor ratio of 1:40 in a sealed stainless steel dyebath housed on the Ahiba Nuance speed varying temperature, contact time and sulphate concentration. Optimal conditions are determined using the experimental designs method. The results show the possibility of chemical auxiliaries free dyeing of cotton fabrics with 1:2 metal complex dye at 75°C for 15 min by treating them with cationizer prior to dyeing. Adsorption kinetic and isotherm are also studied and the parallel exponential model is shown to fit experimental data with higher average regression coefficients

Poly (ADP-ribose) polymerase-1 is a key mediator of liver inflammation and fibrosis.

Poly (ADP-ribose) polymerase 1 (PARP-1) is a constitutive enzyme, the major isoform of the PARP family, which is involved in the regulation of DNA repair, cell death, metabolism, and inflammatory responses. Pharmacological inhibitors of PARP provide significant therapeutic benefits in various preclinical disease models associated with tissue injury and inflammation. However, our understanding the role of PARP activation in the pathophysiology of liver inflammation and fibrosis is limited. In this study we investigated the role of PARP-1 in liver inflammation and fibrosis using acute and chronic models of carbon tetrachloride (CCl4 )-induced liver injury and fibrosis, a model of bile duct ligation (BDL)-induced hepatic fibrosis in vivo, and isolated liver-derived cells ex vivo. Pharmacological inhibition of PARP with structurally distinct inhibitors or genetic deletion of PARP-1 markedly attenuated CCl4 -induced hepatocyte death, inflammation, and fibrosis. Interestingly, the chronic CCl4 -induced liver injury was also characterized by mitochondrial dysfunction and dysregulation of numerous genes involved in metabolism. Most of these pathological changes were attenuated by PARP inhibitors. PARP inhibition not only prevented CCl4 -induced chronic liver inflammation and fibrosis, but was also able to reverse these pathological processes. PARP inhibitors also attenuated the development of BDL-induced hepatic fibrosis in mice. In liver biopsies of subjects with alcoholic or hepatitis B-induced cirrhosis, increased nitrative stress and PARP activation was noted. CONCLUSION: The reactive oxygen/nitrogen species-PARP pathway plays a pathogenetic role in the development of liver inflammation, metabolism, and fibrosis. PARP inhibitors are currently in clinical trials for oncological indications, and the current results indicate that liver inflammation and liver fibrosis may be additional clinical indications where PARP inhibition may be of translational potential

Elaboration and Characterization of Recycled PP/Clay Nanocomposites

In this paper, the elaboration and characterization of recycled polypropylene/Tunisian clay nanocomposites has been investigated. When recycled, polypropylene polymer is degraded and has poorer mechanical and rheological properties. To overcome this problem, we proposed to incorporate Tunisian clay nanoparticles in recycled polypropylene (rPP) matrix. The incorporation of Tunisian clay was performed in molten state using maleic anhydride grafted polypropylene (PP-g-MA) as compatibilizer. The dispersion of clay in rPP polymer was evaluated by scanning electron microscopy and Fourier transformed infrared spectroscopy. Thus, Tunisian clay was more dispersed in nanocomposites with the increase of Tunisian clay loading. In dead, the incorporation of silicate layers gave rise to a considerable increase of the static viscosity demonstrating the reinforcing effect of Tunisian clay nanofillers on rPP matrix. However, the increasing trend of morphological and rheological properties is lower when the clay content exceeds 5%

Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

This paper presents measurements of the $W^+ \rightarrow \mu^+\nu$ and $W^- \rightarrow \mu^-\nu$ cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13

Search for direct stau production in events with two hadronic tau-leptons in root s=13 TeV pp collisions with the ATLAS detector

A search for the direct production of the supersymmetric partners ofτ-leptons (staus) in final stateswith two hadronically decayingτ-leptons is presented. The analysis uses a dataset of pp collisions corresponding to an integrated luminosity of139fb−1, recorded with the ATLAS detector at the LargeHadron Collider at a center-of-mass energy of 13 TeV. No significant deviation from the expected StandardModel background is observed. Limits are derived in scenarios of direct production of stau pairs with eachstau decaying into the stable lightest neutralino and oneτ-lepton in simplified models where the two staumass eigenstates are degenerate. Stau masses from 120 GeV to 390 GeV are excluded at 95% confidencelevel for a massless lightest neutralino

Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in √s=13 TeV pp collisions with the ATLAS detector

A search for supersymmetry through the pair production of electroweakinos with mass splittings near the electroweak scale and decaying via on-shell W and Z bosons is presented for a three-lepton final state. The analyzed proton-proton collision data taken at a center-of-mass energy of √s=13  TeV were collected between 2015 and 2018 by the ATLAS experiment at the Large Hadron Collider, corresponding to an integrated luminosity of 139  fb−1. A search, emulating the recursive jigsaw reconstruction technique with easily reproducible laboratory-frame variables, is performed. The two excesses observed in the 2015–2016 data recursive jigsaw analysis in the low-mass three-lepton phase space are reproduced. Results with the full data set are in agreement with the Standard Model expectations. They are interpreted to set exclusion limits at the 95% confidence level on simplified models of chargino-neutralino pair production for masses up to 345 GeV

Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente