3,940 research outputs found
Corrosion behavior of Shape Memory Alloy in NaCl environment and deformation recovery maintenance in Cu-Zn-Al system
Shape memory effect (SME) and the relation with corrosion behavior of Cu-Zn-Al Smart Memory Alloys (SMAs) were investigated using different techniques: Scanning Electron Microscopy equipped with an Energy Dispersive System, X-Ray Diffraction analysis, Electrochemical Test in NaCl solutions with different concentrations (0.035%, 0.35% and 3.5%), which simulate coastal conditions, mechanical characterization through tensile test and guided bend test. SMAs are an important class of smart materials able to recover after deformation a pre-imposed shape through a temperature modification. These alloys show great potential, finding several applications in medicine and in different types of industry sectors (aerospace, architecture, automotive etc.). Cu-based SMAs, including Cu-Zn-Al alloys, have lower production costs with respect to Ni-Ti alloys as well as good possibility in seismic and architectural applications. A Cu-Zn-Al alloy with a theoretical composition of 25 wt.% Zn and 4 wt.% Al was produced by casting method. The aim of this study is to characterize the microstructure, the mechanical properties and the corrosion behavior through different kind of standard corrosion tests of this alloy and to evaluate the effect of corrosion damage on the shape memory recovery capability through a combination of corrosion and thermo-mechanical cyclic test and SEM observations
The Effects of Incubation Length and Temperature on the Specificity and Sensitivity of the BANA (N‐Benzoyl‐DL‐Arginine‐Naphthylamide) Test
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141244/1/jper0848.pd
Study of the Fusion-Fission Process in the Reaction
Fusion-fission and fully energy-damped binary processes of the
Cl+Mg reaction were investigated using particle-particle
coincidence techniques at a Cl bombarding energy of E
8 MeV/nucleon. Inclusive data were also taken in order to determine the partial
wave distribution of the fusion process. The fragment-fragment correlation data
show that the majority of events arises from a binary-decay process with a
relatively large multiplicity of secondary light-charged particles emitted by
the two primary excited fragments in the exit channel. No evidence is observed
for ternary-breakup processes, as expected from the systematics recently
established for incident energies below 15 MeV/nucleon and for a large number
of reactions. The binary-process results are compared with predictions of
statistical-model calculations. The calculations were performed using the
Extended Hauser-Feshbach method, based on the available phase space at the
scission point of the compound nucleus. This new method uses
temperature-dependent level densities and its predictions are in good agreement
with the presented experimental data, thus consistent with the fusion-fission
origin of the binary fully-damped yields.Comment: 30 pages standard REVTeX file, 10 eps Figures; to be published at the
European Physical Journal A - Hadrons and Nucle
Alpha-particle clustering in excited expanding self-conjugate nuclei
The fragmentation of quasi-projectiles from the nuclear reaction 40Ca + 12C
at 25 MeV/nucleon was used to produce alpha-emission sources. From a careful
selection of these sources provided by a complete detection and from
comparisons with models of sequential and simultaneous decays, strong
indications in favour of -particle clustering in excited 16O, 20Ne and
24}Mg are reported.Comment: 8 pages, 4 figures, 12th International Conference on Nucleus-Nucleus
collisions (NN2015), 21-26 June 2015, Catania, Ital
Quantizing the damped harmonic oscillator
We consider the Fermi quantization of the classical damped harmonic
oscillator (dho). In past work on the subject, authors double the phase space
of the dho in order to close the system at each moment in time. For an
infinite-dimensional phase space, this method requires one to construct a
representation of the CAR algebra for each time. We show that unitary dilation
of the contraction semigroup governing the dynamics of the system is a logical
extension of the doubling procedure, and it allows one to avoid the
mathematical difficulties encountered with the previous method.Comment: 4 pages, no figure
Heart rate responses to social interactions in free-moving rhesus macaques (Macaca mulatta): A pilot study.
Isospin influence on the intermediate-Mass Fragments production at low energy
The reactions 78Kr + 40Ca and 86Kr + 48Ca realized at 10AMeV, have been studied in Catania at LNS with the 4π multidetector CHIMERA. For these systems, we have already studied the fusion-evaporation and fission-like processes. Now we will present a study of the break-up of the Projectile-Like Fragment (PLF) into two fragments, following more violent deep-inelastic collision. A selection method has been developed, in order to discriminate PLF break-up from events due to other mechanisms, fusion-fission–like processes, which populate the same region of the phase-space. A preference for PLF aligned break-up, along the direction of the PLF-TLF separation axis with the light fragment emitted in the backward part, has been evidenced, suggesting dynamical-nonequilibrium effects. The isospin is expected to play a crucial role in the onset of this process; a comparison between the neutron-rich 86Kr + 48Ca system and neutron-poor 78Kr + 40Ca one will be presented
Nosocomial rotavirus gastroenteritis in pediatric patients: a multi-center prospective cohort study.
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