Performance of carbon fiber added to anodes of conductive cement-graphite pastes used in electrochemical chloride extraction in concretes

M. J. Pellegrini-Cervantes,C. P. Barrios-Durstewitz,R. E. Nú,ñ,ez-Jaquez,F. J. Baldenebro-Lopez,R. Corral-Higuera,S. P. Arredondo-Rea,M. Rodriguez-Rodriguez,O. Llanes-Cardenas,R. Beltran-Chaco 한국탄소학회 2018 Carbon Letters Vol.26 No.-

Pollution of chloride ion-reinforced concrete can trigger active corrosion processes that reduce the useful life of structures. Multifunctional materials used as a counter-electrode by electrochemical techniques have been used to rehabilitate contaminated concrete. Cement-based pastes added to carbonaceous material, fibers or dust, have been used as an anode in the non-destructive Electrochemical Chloride Extraction (ECE) technique. We studied the performance of the addition of Carbon Fiber (CF) in a cement-graphite powder base paste used as an anode in ECE of concretes contaminated with chlorides from the preparation of the mixture. The experimental parameters were: 2.3% of free chlorides, 21 days of ECE application, a Carbon Fiber Volume Fraction (CFVF) of 0.1, 0.3, 0.6, 0.9%, a lithium borate alkaline electrolyte, a current density of 4.0 A / m2 and a cement/graphite ratio of 1.0 for the paste. The efficiency of the ECE in the traditional technique using metal mesh as an anode was 77.6% and for CFVF of 0.9% it was 90.4%, with a tendency to increase to higher percentages of the CFVF in the conductive cement-graphite paste, keeping the pH stable and achieving a homogeneous ECE in the mass of the concrete contaminated with chlorides.

Spectroscopic needs for imaging dark energy experiments

Newman, J.A.,Abate, A.,Abdalla, F.B.,Allam, S.,Allen, S.W.,Ansari, R.,Bailey, S.,Barkhouse, W.A.,Beers, T.C.,Blanton, M.R.,Brodwin, M.,Brownstein, J.R.,Brunner, R.J.,Carrasco Kind, M.,Cervantes-Cota, North-Holland 2015 Astroparticle physics Vol.63 No.-

Ongoing and near-future imaging-based dark energy experiments are critically dependent upon photometric redshifts (a.k.a. photo-z's): i.e., estimates of the redshifts of objects based only on flux information obtained through broad filters. Higher-quality, lower-scatter photo-z's will result in smaller random errors on cosmological parameters; while systematic errors in photometric redshift estimates, if not constrained, may dominate all other uncertainties from these experiments. The desired optimization and calibration is dependent upon spectroscopic measurements for secure redshift information; this is the key application of galaxy spectroscopy for imaging-based dark energy experiments. Hence, to achieve their full potential, imaging-based experiments will require large sets of objects with spectroscopically-determined redshifts, for two purposes:*Training: Objects with known redshift are needed to map out the relationship between object color and z (or, equivalently, to determine empirically-calibrated templates describing the rest-frame spectra of the full range of galaxies, which may be used to predict the color-z relation). The ultimate goal of training is to minimize each moment of the distribution of differences between photometric redshift estimates and the true redshifts of objects, making the relationship between them as tight as possible. The larger and more complete our ''training set'' of spectroscopic redshifts is, the smaller the RMS photo-z errors should be, increasing the constraining power of imaging experiments. Requirements: Spectroscopic redshift measurements for ~30,000 objects over >~15 widely-separated regions, each at least ~20arcmin in diameter, and reaching the faintest objects used in a given experiment, will likely be necessary if photometric redshifts are to be trained and calibrated with conventional techniques. Larger, more complete samples (i.e., with longer exposure times) can improve photo-z algorithms and reduce scatter further, enhancing the science return from planned experiments greatly (increasing the Dark Energy Task Force figure of merit by up to ~50%). Options: This spectroscopy will most efficiently be done by covering as much of the optical and near-infrared spectrum as possible at modestly high spectral resolution (λ/Δλ>~3000), while maximizing the telescope collecting area, field of view on the sky, and multiplexing of simultaneous spectra. The most efficient instrument for this would likely be either the proposed GMACS/MANIFEST spectrograph for the Giant Magellan Telescope or the OPTIMOS spectrograph for the European Extremely Large Telescope, depending on actual properties when built. The PFS spectrograph at Subaru would be next best and available considerably earlier, c. 2018; the proposed ngCFHT and SSST telescopes would have similar capabilities but start later. Other key options, in order of increasing total time required, are the WFOS spectrograph at TMT, MOONS at the VLT, and DESI at the Mayall 4m telescope (or the similar 4MOST and WEAVE projects); of these, only DESI, MOONS, and PFS are expected to be available before 2020. Table 2-3 of this white paper summarizes the observation time required at each facility for strawman training samples. To attain secure redshift measurements for a high fraction of targeted objects and cover the full redshift span of future experiments, additional near-infrared spectroscopy will also be required; this is best done from space, particularly with WFIRST-2.4 and JWST. Calibration: The first several moments of redshift distributions (the mean, RMS redshift dispersion, etc.), must be known to high accuracy for cosmological constraints not to be systematics-dominated (equivalently, the moments of the distribution of differences between photometric and true redshifts could be determined instead). The ultimate goal of calibration is to characterize these moments for every subsample used in analyses - i.e., to minimi

Electrical percolation and fluidity of conductive recycled mortar cement: graphite powder: recycled sand with addition of industrial waste carbon fiber

Espinoza-Moreno C. A.,Rodriguez-Rodriguez M.,Pellegrini-Cervantes M. J.,Barrios-Durstewitz C. P.,Núñez-Jaquez R. E.,Peinado-Guevara H. J.,Chinchillas-Chinchillas M.,Fajardo-San-Miguel G. 한국탄소학회 2021 Carbon Letters Vol.31 No.4

The use of recycled materials, such as the fne recycled aggregate made from concrete waste and carbon fber (CF) product of industrial waste, for the manufacture of conductive recycled mortars (CRM), transforms the mortar base cement normally made with cement:sand in a sustainable multifunctional material, conferring satisfactory mechanical and electrical properties for non-structural uses. This action provides ecological benefts, reducing the use of natural fne aggregates from rivers and the amount of concrete waste deposited in landflls resulting from construction waste. In this investigation the efect of the addition of CF on electrical properties in hardened, wet and dry state, electric percolation in dry state and fuidity of the wet mixture of a cement based CRM was evaluated: fne recycled aggregate: graphite powder, CRM specimens with dimensions of 4×4×16 cm. were manufactured for 3, 7 and 28 days of age and sand/cement ratios=1.00, graphite/cement=1.00, water/cement=0.60 and CF=0.1, 0.3, 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0% compared to the weight of cement. The results demonstrated the efect of the addition of CF in CRM, reducing fuidity of the mixtures due to the opposition generated by its physical interaction of CF with recycled sand or recycled fne aggregate and graphite powder (GP), in its case, placing the electric percolation percolation at 0.30% and 0.45% of CF for CRM with and without GP, respectively. Increases in electrical conductivity (EC) without the presence of GP are defned by the contact between the CF and the conductive paths formed. In contrast, with the presence of GP, the EC is defned by the contact between the CF and the GP simultaneously, forming conductive routes with greater performance in its EC.

Protective Effect of Glycomacropeptide on the Atopic Dermatitis-Like Dysfunctional Skin Barrier in Rats

Mariela Jimenez,Fabiola C. Munoz,Daniel Cervantes-Garcıa,Maritza M. Cervantes,Alicia Hernandez-Mercado,Berenice Barron-Garcıa,Jose L. Moreno Hernandez-Duque,Adrian Rodrıguez-Carlos,Bruno Rivas-Santiag 한국식품영양과학회 2020 Journal of medicinal food Vol.23 No.11

The maintenance of a healthy skin barrier is crucial to prevent and treat atopic dermatitis (AD) lesions and avoid infections. Glycomacropeptide (GMP) is a bioactive peptide that has demonstrated promising results as an anti-inflammatory and antipruritic therapy for experimental AD. This study aimed to analyze the effect of GMP on impaired cutaneous barrier-related signs in a rat model of AD lesions. AD-like dermatitis was induced on the skin by repeated topical applications of 2,4-dinitrochlorobenzene, and animals were orally administered GMP before or after AD induction. The expression of skin structural proteins and antimicrobial peptides (AMPs) was evaluated by immunoblot or immunohistochemistry, epidermal thickening was evaluated by histochemistry, the level of IFN-γ and changes in the microbiota were evaluated by quantitative polymerase chain reaction, and the quantity of fecal short-chain fatty acids (SCFAs) was evaluated by gas chromatography. GMP administration significantly increased filaggrin, β-defensin 2, and cathelicidin-related AMP expression in AD-like lesions. Involucrin expression was not modified. In GMP-treated animals, epidermal thickening and IFN-γ expression were strongly reduced in damaged skin. GMP treatment impacted the skin microbiota and prevented Staphylococcus aureus colonization, which is associated with AD. In addition, high levels of Bifidobacterium were detected in the feces of GMP-treated animals, and the acetic acid and butyric acid contents increased in animals prophylactically administered GMP. These results suggest that GMP markedly prevents or reverses skin barrier damage in rat AD-like lesions through a bifidogenic effect that induces fecal SCFA production with prolonged treatment. Our findings provide evidence that GMP may represent an optimum strategy for the therapy of the dysfunctional cutaneous barrier in AD.

First constraint on coherent elastic neutrino-nucleus scattering in argon

Akimov, D.,Albert, J. B.,An, P.,Awe, C.,Barbeau, P. S.,Becker, B.,Belov, V.,Blackston, M. A.,Bolozdynya, A.,Cabrera-Palmer, B.,Cervantes, M.,Collar, J. I.,Cooper, R. L.,Daughhetee, J.,del Valle Coello American Physical Society 2019 Physical review. D Vol.100 No.11

Observation of coherent elastic neutrino-nucleus scattering

Akimov, D.,Albert, J. B.,An, P.,Awe, C.,Barbeau, P. S.,Becker, B.,Belov, V.,Brown, A.,Bolozdynya, A.,Cabrera-Palmer, B.,Cervantes, M.,Collar, J. I.,Cooper, R. J.,Cooper, R. L.,Cuesta, C.,Dean, D. J.,D American Association for the Advancement of Scienc 2017 Science Vol.357 No.6356

<P>The coherent elastic scattering of neutrinos off nuclei has eluded detection for four decades, even though its predicted cross section is by far the largest of all low-energy neutrino couplings. This mode of interaction offers new opportunities to study neutrino properties and leads to a miniaturization of detector size, with potential technological applications. We observed this process at a 6.7s confidence level, using a low-background, 14.6-kilogram CsI[Na] scintillator exposed to the neutrino emissions from the Spallation Neutron Source at Oak Ridge National Laboratory. Characteristic signatures in energy and time, predicted by the standard model for this process, were observed in high signal-to-background conditions. Improved constraints on nonstandard neutrino interactions with quarks are derived from this initial data set.</P>