1,174 research outputs found
Particle Ratios and the QCD Critical Temperature
We show how the measured particle ratios at RHIC can be used to provide
non-trivial information about the critical temperature of the QCD phase
transition. This is obtained by including the effects of highly massive
Hagedorn resonances on statistical models, which are used to describe hadronic
yields. Hagedorn states are relevant close to and have been shown to
decrease to the KSS limit and allow for quick chemical equilibrium
times in dynamical calculations of hadrons. The inclusion of Hagedorn states
creates a dependence of the thermal fits on the Hagedorn temperature, ,
which is assumed to be equal to , and leads to an overall improvement of
thermal fits. We find that for Au+Au collisions at RHIC at
GeV the best square fit measure, , occurs at MeV and
produces a chemical freeze-out temperature of 170.4 MeV and a baryon chemical
potential of 27.8 MeV.Comment: 6 pages, 2 figures, talk presented at the International Conference on
Strangeness in Quark Matter, Buzios, Rio de Janeiro, Brazil, Sept. 27 - oct.
2, 200
Polyakov Loops in Strongly-Coupled Plasmas with Gravity Duals
We study the properties of the Polyakov loop in strongly-coupled gauge
plasmas that are conjectured to be dual to five dimensional theories of gravity
coupled to a nontrivial single scalar field. We find a gravity dual that can
describe the thermodynamic properties and also the expectation value of the
Polyakov loop in the deconfined phase of quenched SU(3) QCD up to .Comment: 7 pages, 2 figures, talk presented at the International Conference on
Strangeness in Quark Matter, Buzios, Rio de Janeiro, Brazil, Sept. 27 - oct.
2, 200
Hidden Order in Crackling Noise during Peeling of an Adhesive Tape
We address the long standing problem of recovering dynamical information from
noisy acoustic emission signals arising from peeling of an adhesive tape
subject to constant traction velocity. Using phase space reconstruction
procedure we demonstrate the deterministic chaotic dynamics by establishing the
existence of correlation dimension as also a positive Lyapunov exponent in a
mid range of traction velocities. The results are explained on the basis of the
model that also emphasizes the deterministic origin of acoustic emission by
clarifying its connection to sticks-slip dynamics.Comment: 5 pages, 10 figure
Emerging (Bio)Sensing Technology for Assessing and Monitoring Freshwater Contamination - Methods and Applications
Ecological Water Quality - Water Treatment and ReuseWater is life and its preservation is not only a moral obligation but also a legal requirement.
By 2030, global demands will exceed more than 40 % the existing resources and more than a
third of the world's population will have to deal with water shortages (European
Environmental Agency [EEA], 2010). Climate change effects on water resources will not
help. Efforts are being made throughout Europe towards a reduced and efficient water use
and prevention of any further deterioration of the quality of water (Eurostat, European
Comission [EC], 2010). The Water Framework Directive (EC, 2000) lays down provisions for
monitoring, assessing and classifying water quality. Supporting this, the Drinking Water
sets standards for 48 microbiological and chemical parameters that must be monitored and
tested regularly (EC, 1998). The Bathing Water Directive also sets concentration limits for
microbiological pollutants in inland and coastal bathing waters (EC, 2006), addressing risks
from algae and cyanobacteria contamination and faecal contamination, requiring immediate
action, including the provision of information to the public, to prevent exposure. With these
directives, among others, the European Union [EU] expects to offer its citizens, by 2015,
fresh and coastal waters of good quality
Label-free Detection of Microcystin-LR in Waters Using Real-Time Potentiometric Biosensors Based on Single-Walled Carbon Nanotubes Imprinted Polymers
Microcystin-LR (MC-LR) is a dangerous toxin found in environmental waters, quantified by high performance liquid chromatography and/or enzyme-linked immunosorbent assays. Quick, low cost and on-site analysis is thus required to ensure human safety and wide screening programs. This work proposes label-free potentiometric sensors made of solid-contact electrodes coated with a surface imprinted polymer on the surface of Multi-Walled Carbon NanoTubes (CNTs) incorporated in a polyvinyl chloride membrane. The imprinting effect was checked by using non-imprinted materials. The MC-LR sensitive sensors were evaluated, characterized and applied successfully in spiked environmental waters. The presented method offered the advantages of low cost, portability, easy operation and suitability for adaptation to flow methods
O Comportamento Cíclico do Capital dos Bancos Brasileiros
In the context of the implementation of the Basel II accord, this paper analyzes the cyclical behavior of Brazilian bank capital under the current regulation. We use an unbalanced panel data of banks operating in Brazil between 2003 and 2008 to estimate an equation of the bank economic capital. Our results show that this variable moves with the business cycle.
- …