Universidad Iberoamericana Ciudad de México

About: Universidad Iberoamericana Ciudad de México is a education organization based out in Mexico City, Mexico. It is known for research contribution in the topics: Large Hadron Collider & Standard Model. The organization has 2259 authors who have published 3981 publications receiving 109298 citations.

Efficient Anodic Degradation of Phenol Paired to Improved Cathodic Production of H2O2 at BDD Electrodes

Abstract: Electrochemical degradation of phenol (PhOH) with simultaneous reduction of O2(g) to H2O2 in acidic media was performed in an H-type divided cell (500 mL), separated with a cationic membrane (Nafion 424). Boron-doped diamond (BDD) electrodes were used as anode and cathode. The study was divided into three stages: (a) Electroanalytical study of the oxygen reduction reaction (ORR) to H2O2 by hydrodynamic linear-sweep voltammetry with a BDD-RDE in acidic and alkaline solutions; (b) galvanostatic ORR to H2O2 at BDD electrode in acidic solution (unpaired system); (c) pairing the anodic PhOH degradation with the H2O2 cathodic production at BDD electrodes. The best production of H2O2 under our conditions with the unpaired system was 250.1 mg L−1 at 1.5 mA cm−2 after 540 min of electrolysis, the highest reported to date for BDD electrode in acidic media. Total mineralization of 100 mg L−1 of PhOH in the paired system required a higher current density (i.e., 2.5 mA cm−2); in spite of this, the process is one order of magnitude faster than any electrochemical process previously reported. © 2013 The Electrochemical Society. [DOI: 10.1149/2.027307jes] All rights reserved.

Measurement of the top-quark mass in all-jets tt̄ events in pp collisions at √s = 7 TeV

Abstract: The mass of the top quark is measured using a sample of $t\bar{t}$ candidate events with at least six jets in the final state. The sample is selected from data collected with the CMS detector in pp collisions at $\sqrt{s}$ = 7 TeV in 2011 and corresponds to an integrated luminosity of 3.54 inverse femtobarns. The mass is reconstructed for each event employing a kinematic fit of the jets to a $t\bar{t}$ hypothesis. The top-quark mass is measured to be 173.49 $\pm$ 0.69 (stat.) $\pm$ 1.21 (syst.) GeV. A combination with previously published measurements in other decay modes by CMS yields a mass of 173.54 $\pm$ 0.33 (stat.) $\pm$ 0.96 (syst.) GeV.

Search for heavy resonances decaying to two Higgs bosons in final states containing four b quarks

Abstract: A search is presented for narrow heavy resonances X decaying into pairs of Higgs bosons (H) in proton-proton collisions collected by the CMS experiment at the LHC at sqrt(s)=8 TeV. The data correspond to an integrated luminosity of 19.7 inverse femtobarns. The search considers HH resonances with masses between 1 and 3 TeV, having final states of two b quark pairs. Each Higgs boson is produced with large momentum, and the hadronization products of the pair of b quarks can usually be reconstructed as single large jets. The background from multijet and t-tbar events is significantly reduced by applying requirements related to the flavor of the jet, its mass, and its substructure. The signal would be identified as a peak on top of the dijet invariant mass spectrum of the remaining background events. No evidence is observed for such a signal. Upper limits obtained at 95% confidence level for the product of the production cross section and branching fraction sigma(gg to X) B(X to HH to b-bbar b-bbar) range from 10 to 1.5 fb for the mass of X from 1.15 to 2.0 TeV, significantly extending previous searches. For a warped extra dimension theory with a mass scale Lambda[R] = 1 TeV, the data exclude radion scalar masses between 1.15 and 1.55 TeV.

Pigmentation of pacific white shrimp (Litopenaeus vannamei, Boone 1931) with esterified and saponified carotenoids from red chili Capsicum annuum) in comparison to astaxanthin

Abstract: Resumen en: Pacific white shrimp were fed diets containing esterified and saponified carotenoids obtained from red chili extracts. The pigmenting effect of these car...

Search for physics beyond the standard model in events with jets and two same-sign or at least three charged leptons in proton-proton collisions at s=13TeV.

Abstract: A data sample of events from proton-proton collisions with at least two jets, and two isolated same-sign or three or more charged leptons, is studied in a search for signatures of new physics phenomena. The data correspond to an integrated luminosity of 137fb-1 at a center-of-mass energy of 13TeV , collected in 2016-2018 by the CMS experiment at the LHC. The search is performed using a total of 168 signal regions defined using several kinematic variables. The properties of the events are found to be consistent with the expectations from standard model processes. Exclusion limits at 95% confidence level are set on cross sections for the pair production of gluinos or squarks for various decay scenarios in the context of supersymmetric models conserving or violating R parity. The observed lower mass limits are as large as 2.1TeV for gluinos and 0.9TeV for top and bottom squarks. To facilitate reinterpretations, model-independent limits are provided in a set of simplified signal regions.