Technological Evaluation of Cubati/Brazil Montmorillonite / Avaliação Tecnológica da Montmorillonita de Cubati/Brasil

The aim of this work was the technological characterization of sample fraction from Cubati region, Pedra Lavrada – Paraíba State, Brazil, in order to evaluate its further applications as drug adsorber and as oil drilling fluid. The sample had been properly processed and characterized by X-ray diffractometry, X-ray fluorescence spectroscopy, cation exchange capacity, thermo-differential and thermogravimetric analysis, determination of textural properties by BET and B.J.H. methods, Fourier transform infrared spectroscopy and surface charge measurements by means of Zeta potential. The results obtained showed that the studied sample is essentially composed by montmorillonite (smectite), kaolinite, quartz and dolomite, with high contents of silica (37.4%), alumina (17.2%), calcium oxide (5.7%) and iron oxide (7.5%). The CEC value obtained (41.0 meq 100 g-1), is due to the presence of kaolinite, which was confirmed by XRD, DTA-TG/DTG and FTIR results. BET and B.J.H. models showed that it is a mesoporous clay mineral, with a surface area of 84.81 m2 g-1. The surface charge measurement by Zeta Potential showed that this clay mineral is negatively charged in almost all of pH range studied. Thus, it has high adsorptive potential of drugs cationic species, while activation with sodium carbonate associated with organophilization process allow its application as oil drilling fluid

Azimuthal anisotropy of charged jet production in root s(NN)=2.76 TeV Pb-Pb collisions

We present measurements of the azimuthal dependence of charged jet production in central and semi-central root s(NN) = 2.76 TeV Pb-Pb collisions with respect to the second harmonic event plane, quantified as nu(ch)(2) (jet). Jet finding is performed employing the anti-k(T) algorithm with a resolution parameter R = 0.2 using charged tracks from the ALICE tracking system. The contribution of the azimuthal anisotropy of the underlying event is taken into account event-by-event. The remaining (statistical) region-to-region fluctuations are removed on an ensemble basis by unfolding the jet spectra for different event plane orientations independently. Significant non-zero nu(ch)(2) (jet) is observed in semi-central collisions (30-50% centrality) for 20 <p(T)(ch) (jet) <90 GeV/c. The azimuthal dependence of the charged jet production is similar to the dependence observed for jets comprising both charged and neutral fragments, and compatible with measurements of the nu(2) of single charged particles at high p(T). Good agreement between the data and predictions from JEWEL, an event generator simulating parton shower evolution in the presence of a dense QCD medium, is found in semi-central collisions. (C) 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Peer reviewe

Production of He-4 and (4) in Pb-Pb collisions at root(NN)-N-S=2.76 TeV at the LHC

Results on the production of He-4 and (4) nuclei in Pb-Pb collisions at root(NN)-N-S = 2.76 TeV in the rapidity range vertical bar y vertical bar <1, using the ALICE detector, are presented in this paper. The rapidity densities corresponding to 0-10% central events are found to be dN/dy4(He) = (0.8 +/- 0.4 (stat) +/- 0.3 (syst)) x 10(-6) and dN/dy4 = (1.1 +/- 0.4 (stat) +/- 0.2 (syst)) x 10(-6), respectively. This is in agreement with the statistical thermal model expectation assuming the same chemical freeze-out temperature (T-chem = 156 MeV) as for light hadrons. The measured ratio of (4)/He-4 is 1.4 +/- 0.8 (stat) +/- 0.5 (syst). (C) 2018 Published by Elsevier B.V.Peer reviewe

Forward-central two-particle correlations in p-Pb collisions at root s(NN)=5.02 TeV

Two-particle angular correlations between trigger particles in the forward pseudorapidity range (2.5 2GeV/c. (C) 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B. V.Peer reviewe

Event-shape engineering for inclusive spectra and elliptic flow in Pb-Pb collisions at root(NN)-N-S=2.76 TeV

Peer reviewe

Pseudorapidity and transverse-momentum distributions of charged particles in proton-proton collisions at root s=13 TeV

The pseudorapidity (eta) and transverse-momentum (p(T)) distributions of charged particles produced in proton-proton collisions are measured at the centre-of-mass energy root s = 13 TeV. The pseudorapidity distribution in vertical bar eta vertical bar <1.8 is reported for inelastic events and for events with at least one charged particle in vertical bar eta vertical bar <1. The pseudorapidity density of charged particles produced in the pseudorapidity region vertical bar eta vertical bar <0.5 is 5.31 +/- 0.18 and 6.46 +/- 0.19 for the two event classes, respectively. The transverse-momentum distribution of charged particles is measured in the range 0.15 <p(T) <20 GeV/c and vertical bar eta vertical bar <0.8 for events with at least one charged particle in vertical bar eta vertical bar <1. The evolution of the transverse momentum spectra of charged particles is also investigated as a function of event multiplicity. The results are compared with calculations from PYTHIA and EPOS Monte Carlo generators. (C) 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Peer reviewe

Elliptic flow of muons from heavy-flavour hadron decays at forward rapidity in Pb-Pb collisions at root s(NN)=2.76TeV

The elliptic flow, v(2), of muons from heavy-flavour hadron decays at forward rapidity (2.5 <y <4) is measured in Pb-Pb collisions at root s(NN)= 2.76TeVwith the ALICE detector at the LHC. The scalar product, two- and four-particle Q cumulants and Lee-Yang zeros methods are used. The dependence of the v(2) of muons from heavy-flavour hadron decays on the collision centrality, in the range 0-40%, and on transverse momentum, p(T), is studied in the interval 3 <p(T)<10 GeV/c. A positive v(2) is observed with the scalar product and two-particle Q cumulants in semi-central collisions (10-20% and 20-40% centrality classes) for the p(T) interval from 3 to about 5GeV/c with a significance larger than 3 sigma, based on the combination of statistical and systematic uncertainties. The v(2) magnitude tends to decrease towards more central collisions and with increasing pT. It becomes compatible with zero in the interval 6 <p(T)<10 GeV/c. The results are compared to models describing the interaction of heavy quarks and open heavy-flavour hadrons with the high-density medium formed in high-energy heavy-ion collisions. (C) 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B.V.Peer reviewe

Centrality evolution of the charged-particle pseudorapidity density over a broad pseudorapidity range in Pb-Pb collisions at root s(NN)=2.76TeV

Peer reviewe

not available

O presente trabalho teve por objetivo analisar algumas variáveis relacionadas à evolução do setor agrícola goiano, e especificamente o sub-setor de lavouras, para o período 1975-84. Foi utilizado o modelo"shift-share", o qual permite decompor a taxa anual de crescimento da produção nos seguintes efeitos: área (decomposto em efeitos escala e substituição), rendimento, composição da produção e localização geográfica. O modelo"shift-share"pode ser utilizado em três momentos: Análise individual por cultura; Análise agregada por região; e Análise agregada para o Estado. Apesar de uma elevada taxa de crescimento da produção, no período 1975-84, de 5,36% ao ano, os resultados obtidos mostraram haver diferenças entre as regiões do norte e sul do Estado de Goiás. Enquanto a região sul apresenta sinais de modernização da agricultura, a região norte mostrou, com algumas exceções, um crescimento baseado em técnicas tradicionais. Um dos aspectos mais importantes relativos à evolução do setor agrícola goiano nos últimos anos diz respeito à expansão da soja, sobretudo nas regiões do sul do estado. Com os resultados obtidos permite-se antever consequências que advirão do desmembramento do estado de Tocantins, do norte do atual território de Goiás, de acordo com resolução incorporada na nova constituiçãoThe objective of this study is to analyse the changes that ocurred in agricultural sector of the state of Goiás, Brazil, in the period 1975-1984. For a systematic statistical evaluation of agricultural data, it was used"shift-share"analysis, which allowed to decompose the annual growth tax rate of agricultural output in the following effects: area (scale and sustitution), yield, output mix (or composition of activities) and regional redistribution. Three ranks of statistical evaluation were possible to be made usig"shift-share"model: individual analysis, that studies each crop isolatedly, including scale and sustitution effects; aggregated analysis by regions; and aggregated analysis for agriculture of the state of Goiás as a whole. Although the increasing annual tax rate of Goiás agricultural production (5,36% annually for the period 1975-1984), the results have shown differences between northern and southern portions of the state. While the southern sector of the state has presented signals og agriculture modernization, the northern regions have revealed, with few exceptions, traditional standards of expansion of agricultural sector. One of the most important aspects of agricultural sector evolution in the State of Goiás is related to the expansion of soybean cultivated area, especially in its southern regions. The result are useful for improving the agricultural policies formulation. They also allowed to forecast some administratives and geopolitics|consequences resulting from the detaching of the State of Tocantins from tthe actual northern portion of the State of Goiás territor