Caracterização mecânica das argamassas de assentamento para alvenaria estrutural – previsão e modo de ruptura

Este trabalho pretende avaliar o comportamento mecânico das argamassas de assentamento para o uso estrutural, por meio das propriedades de resistência à compressão, tração na flexão e módulo de elasticidade, sob estados de tensões uniaxial e multiaxial. Portanto, estabelecer correlações entre os resultados mecânicos de diferentes traços de argamassas, relações água/cimento e geometria da amostra associada ao modo de ruptura. As principais conclusões obtidas, entre outras, são: existe uma relação potencial entre a resistência a compressão da amostra de geometria cúbica, cilíndrica e a resistência à flexão (amostra de geometria prismática) em função da relação água/cimento; a função linear é a que melhor ajusta os valores médios do módulo de elasticidade em função da resistência à compressão; a envoltória de ruptura da argamassa confinada lateralmente pode ser representada como uma relação linear de Mohr-Coulomb; observou-se, por meio de ensaios de microscopia eletrônica de varredura a existência de fissuras de retração na interface pasta-agregado e poros isolados, devido ao fluxo ascendente de água causado pela exsudação

Ferromagnetism in the Two-Dimensional Periodic Anderson Model

Using the constrained-path Monte Carlo method, we studied the magnetic properties of the two-dimensional periodic Anderson model for electron fillings between 1/4 and 1/2. We also derived two effective low energy theories to assist in interpreting the numerical results. For 1/4 filling we found that the system can be a Mott or a charge transfer insulator, depending on the relative values of the Coulomb interaction and the charge transfer gap between the two non-interacting bands. The insulator may be a paramagnet or antiferromagnet. We concentrated on the effect of electron doping on these insulating phases. Upon doping we obtained a partially saturated ferromagnetic phase for low concentrations of conduction electrons. If the system were a charge transfer insulator, we would find that the ferromagnetism is induced by the well-known RKKY interaction. However, we found a novel correlated hopping mechanism inducing the ferromagnetism in the region where the non-doped system is a Mott insulator. Our regions of ferromagnetism spanned a much smaller doping range than suggested by recent slave boson and dynamical mean field theory calculations, but they were consistent with that obtained by density matrix renormalization group calculations of the one-dimensional periodic Anderson model

Measurement of charm production at central rapidity in proton-proton collisions at s=2.76\sqrt{s} = 2.76 TeV

The $p_{\rm T}$-differential production cross sections of the prompt (B feed-down subtracted) charmed mesons D$^0$, D$^+$, and D$^{*+}$ in the rapidity range $|y|<0.5$, and for transverse momentum $1< p_{\rm T} <12$ GeV/$c$, were measured in proton-proton collisions at $\sqrt{s} = 2.76$ TeV with the ALICE detector at the Large Hadron Collider. The analysis exploited the hadronic decays D$^0 \rightarrow$K$\pi$, D$^+ \rightarrow$K$\pi\pi$, D$^{*+} \rightarrow$D$^0\pi$, and their charge conjugates, and was performed on a $L_{\rm int} = 1.1$ nb$^{-1}$ event sample collected in 2011 with a minimum-bias trigger. The total charm production cross section at $\sqrt{s} = 2.76$ TeV and at 7 TeV was evaluated by extrapolating to the full phase space the $p_{\rm T}$-differential production cross sections at $\sqrt{s} = 2.76$ TeV and our previous measurements at $\sqrt{s} = 7$ TeV. The results were compared to existing measurements and to perturbative-QCD calculations. The fraction of cdbar D mesons produced in a vector state was also determined.Comment: 20 pages, 5 captioned figures, 4 tables, authors from page 15, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/307

Particle-yield modification in jet-like azimuthal di-hadron correlations in Pb-Pb collisions at sNN\sqrt{s_{\rm NN}} = 2.76 TeV

The yield of charged particles associated with high-$p_{\rm T}$ trigger particles ($8 < p_{\rm T} < 15$ GeV/$c$) is measured with the ALICE detector in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV relative to proton-proton collisions at the same energy. The conditional per-trigger yields are extracted from the narrow jet-like correlation peaks in azimuthal di-hadron correlations. In the 5% most central collisions, we observe that the yield of associated charged particles with transverse momenta $p_{\rm T}> 3$ GeV/$c$ on the away-side drops to about 60% of that observed in pp collisions, while on the near-side a moderate enhancement of 20-30% is found.Comment: 15 pages, 2 captioned figures, 1 table, authors from page 10, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/350

A unified matrix approach to the representation of Appell polynomials

In this paper, we propose a unified approach to matrix representations of different types of Appell polynomials. This approach is based on the creation matrix – a special matrix which has only the natural numbers as entries and is closely related to the well-known Pascal matrix. By this means, we stress the arithmetical origins of Appell polynomials. The approach also allows to derive, in a simplified way, the properties of Appell polynomials by using only matrix operations

The HERschel inventory of the agents of galaxy evolution in the Magellanic clouds, a HERschel open time key program

We present an overview of the HERschel Inventory of The Agents of Galaxy Evolution (HERITAGE) in the Magellanic Clouds project, which is a Herschel Space Observatory open time key program. We mapped the Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC) at 100, 160, 250, 350, and 500 μm with the Spectral and Photometric Imaging Receiver (SPIRE) and Photodetector Array Camera and Spectrometer (PACS) instruments on board Herschel using the SPIRE/PACS parallel mode. The overriding science goal of HERITAGE is to study the life cycle of matter as traced by dust in the LMC and SMC. The far-infrared and submillimeter emission is an effective tracer of the interstellar medium (ISM) dust, the most deeply embedded young stellar objects (YSOs), and the dust ejected by the most massive stars. We describe in detail the data processing, particularly for the PACS data, which required some custom steps because of the large angular extent of a single observational unit and overall the large amount of data to be processed as an ensemble. We report total global fluxes for the LMC and SMC and demonstrate their agreement with measurements by prior missions. The HERITAGE maps of the LMC and SMC are dominated by the ISM dust emission and bear most resemblance to the tracers of ISM gas rather than the stellar content of the galaxies. We describe the point source extraction processing and the criteria used to establish a catalog for each waveband for the HERITAGE program. The 250 μm band is the most sensitive and the source catalogs for this band have ∼25,000 objects for the LMC and ∼5500 objects for the SMC. These data enable studies of ISM dust properties, submillimeter excess dust emission, dust-to-gas ratio, Class 0 YSO candidates, dusty massive evolved stars, supernova remnants (including SN1987A), H II regions, and dust evolution in the LMC and SMC. All images and catalogs are delivered to the Herschel Science Center as part of the community support aspects of the project. These HERITAGE images and catalogs provide an excellent basis for future research and follow up with other facilities. © 2013. The American Astronomical Society. All rights reserved

Revealing the spatio-phenotypic patterning of cells in healthy and tumor tissues with mLSR-3D and STAPL-3D

Stem cells & developmental biolog

Centrality Dependence Of The Pseudorapidity Density Distribution For Charged Particles In Pb-pb Collisions At √snn=2.76tev

7264/Mai61062

Long-range Angular Correlations On The Near And Away Side In P-pb Collisions At √snn=5.02 Tev

7191/Mar294