Search results for "Measurement"
showing 10 items of 2918 documents
Cavitation corrosion and repassivation kinetics of titanium in a heavy brine LiBr solution evaluated by using electrochemical techniques and Confocal…
2011
The cavitation corrosion behaviour of commercially pure Grade 2 titanium in a 992 g/l LiBr solution has been investigated at 25 °C using an ultrasound device. Cavitation was found to have more influence on the anodic branch than on the cathodic branch, shifting the corrosion potential, Ecorr, and the OCP value towards more negative potentials, and increasing the corrosion current density, icorr, by six times. The repassivation kinetics of Grade 2 titanium have also been studied in the 992 g/l LiBr solution, at 25 °C and various applied potentials, using cavitation to damage the electrode surface. The repassivation kinetics have been analysed in terms of the current density flowing from the …
The Formal Redox Potential of the Ti(IV, III) Couple at 25 °C in 1 M HCl 2 M NaCl Medium
2007
The formal redox potential of the Ti(IV, III) couple has been determined at 25 degrees C in 1 M HCl, 2 M NaCl aqueous medium, by emf measurements of a junction-free cell with glass and mercury electrodes. Ti(III) and Ti(IV) concentrations were changed by controlled electrolysis. The mean value of the searched formal potential, in a large range of total titanium concentration, is 9 +/- 1 mV against the molar hydrogen electrode in the same ionic medium.
Metabolic mapping with bioluminescence: basic and clinical relevance
2002
This review is focused on metabolic mapping in biological tissue with quantitative bioluminescence and single photon imaging. Metabolites, such as ATP, glucose and lactate, can be imaged quantitatively and within microscopic dimensions in cryosections from shock frozen biological specimens using enzyme reactions and light emission by luciferases. The technique has been applied in numerous targets and models of experimental biomedical research, such as multicellular spheroids, various organs of laboratory animals in a physiological or pathophysiological state, and even in plant seeds. Among numerous other aspects, data obtained with this method have contributed to the elucidation of mechanis…
Precision electroweak measurements on the Z resonance
2005
We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLD experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, $\MZ$ and $\GZ$, and its couplings to fermions, for example the $\rho$ parameter and the effective electroweak mixing angle, are precisely measured. The number of light neutrino species is determined to be 2.9840…
Electroweak measurements in electron-positron collisions at W-boson-pair energies at LEP
2013
The ALEPH, DELPHI, L3, OPAL collaborations and LEP Electroweak Working Group.-- arXiv:1302.3415
Cross-section-constrained top-quark mass measurement from dilepton events at the tevatron
2008
We report the first top quark mass measurement that uses a cross section constraint to improve the mass determination. This measurement is made with a dilepton $t\bar{t}$ event sample collected with the CDF II detector. From a data sample corresponding to an integrated luminosity of 1.2 fb$^{-1}$, we measure a top quark mass of $\rm{170.7^{+4.2}_{-3.9}(stat)\pm2.6(syst)}$ $\rm{\pm2.4(theory) GeV/{\it{c}}^{2}}$. The measurement without the cross section constraint results in a top quark mass of $\rm{169.7^{+5.2}_{-4.9}(stat)\pm3.1(syst) GeV/{\it{c}}^{2}}$.
Total absorption spectroscopy of fission fragments relevant for reactor antineutrino spectra
2016
International audience; The accurate determination of reactor antineutrino spectra remains a very active research topic for which new methods of study have emerged in recent years. Indeed, following the long-recognized reactor anomaly (measured antineutrino deficit in short baseline reactor experiments when compared with spectral predictions), the three international reactor neutrino experiments Double Chooz, Daya Bay and Reno have recently demonstrated the existence of spectral distortions in their measurements with respect to the same predictions. These spectral predictions were obtained through the conversion of integral beta-energy spectra obtained at the ILL research reactor. Several s…
A self-synchronizing instrument for harmonic sources detection in power systems
2004
The deregulation of energy markets holds out new prospects for contract between customers and utilities, in which the price of energy can depend on voltage quality and load characteristics, as well as on the responsibility for disturbances caused to supply voltage in power systems. In this context, harmonic sources detection is one of the main problems, because of equipment sensibility and the proliferation of loads which absorb non-sinusoidal currents. In this paper the authors present a new instrument based on a time domain method for the detection of harmonic active powers in three-phase systems, which can be usefully applied even in the presence of unbalance or asymmetry. The amplitude …
Metrological characterization and operating principle identification of static meters for reactive energy: an experimental approach under nonsinusoid…
2009
In this paper, an experimental approach is proposed for the metrological characterization of the static meters for reactive energy and for the individuation of their operating principle in nonsinusoidal conditions. The proposed approach was developed by starting from the only available accuracy test condition in the presence of the harmonics introduced by the standards for active static meters. In this paper, the proposed approach is described, and some experimental tests are presented, which were performed on some meters of different accuracy classes and with both known and unknown operating principles.
Polluting loads detection in power systems: a decision-making strategy based on nonactive power measurements
2010
In this paper a novel decision-making strategy is proposed for the detection of polluting loads in three-phase power systems. It makes use of simple indices, which are expressed as a function of some nonactive power quantities, previously proposed by the authors and derived from the approach of the IEEE Std. 1459–2000. The decision-making rules for the proposed strategy are presented and discussed, by means of some simulation tests.