A5087480497- Magnetic Properties and Applications
- Shape Memory Alloy Transformations
- Magnetic and transport properties of perovskites and related materials
- Scientific Measurement and Uncertainty Evaluation
- Magnetic properties of thin films
- Advanced Measurement and Metrology Techniques
- Microstructure and Mechanical Properties of Steels
- Magnetic Properties of Alloys
- Radioactive Decay and Measurement Techniques
- Nuclear Physics and Applications
- Advanced Sensor Technologies Research
- Non-Destructive Testing Techniques
- Metallic Glasses and Amorphous Alloys
- Rare-earth and actinide compounds
- Theoretical and Computational Physics
- Advanced Thermodynamics and Statistical Mechanics
- Anodic Oxide Films and Nanostructures
- Calibration and Measurement Techniques
- Advanced X-ray Imaging Techniques
- Atomic and Subatomic Physics Research
- Magnetic Properties and Synthesis of Ferrites
- Nanoporous metals and alloys
- Optical measurement and interference techniques
- Advanced Electrical Measurement Techniques
- Quantum, superfluid, helium dynamics
Istituto Nazionale di Ricerca Metrologica
2015-2024
Istituto Nazionale di Fisica Nucleare, Galileo Galilei Institute for Theoretical Physics
1999-2006
Ferrari (Italy)
2000-2006
Polytechnic University of Turin
2001-2002
Osservatorio Astrofisico di Torino
2002
A first order transition from a paramagnetic-austenite phase to ferromagnetic-martensite occurring in off-stoichiometry single crystals of ${\mathrm{Ni}}_{2}\mathrm{Mn}\mathrm{Ga}$ at 313 K presents unique features due the multifunctional character magnetic shape memory alloy. remarkable magnetocaloric effect, associated with an entropy change up...
New results are reported from an ongoing international research effort to accurately determine the Avogadro constant by counting atoms in isotopically enriched silicon crystal. The surfaces of two 28Si-enriched spheres were decontaminated and reworked order produce outer surface without metal contamination improved sphericity. measurements then made on these reconditioned using methods apparatuses. When combined with other recently refined parameter measurements, derived new has a value NA =...
Hysteresis features of the direct and inverse magnetocaloric effect associated with first-order magnetostructural phase transitions in Ni-Mn-X (X $=$ Ga, Sn) Heusler alloys have been disclosed by differential calorimetry measurements performed either under a constant magnetic field, $H$, or varying $H$ isothermal conditions. We shown that these crucially depends on employed measuring protocol. Experimentally observed peculiarities explained framework model accounts for different...
A new single crystal from isotopically enriched silicon was used to determine the Avogadro constant NA by x-ray-crystal density method. The crystal, named Si28-23Pr11, has a higher enrichment than former 'AVO28' allowing smaller uncertainty of molar mass determination. Again, two 1 kg spheres were manufactured this crystal. and measured with improved methods. One sphere, Si28kg01a, at NMIJ PTB very consistent results. other Si28kg01b, only yielded nearly same value. mean result for both is =...
In 2011, a discrepancy between the values of Planck constant measured by counting Si atoms and comparing mechanical electrical powers prompted review, among others, measurement spacing 28Si {220} lattice planes, either to confirm value its uncertainty or identify errors. This exercise confirmed result previous yields additional d220 = 192 014 711.98(34) am having reduced uncertainty.
In this paper we describe and test a setup for the characterization of magnetocaloric effect around room temperature. The is differential calorimeter able to measure both specific heat c(p)(H,T) under constant magnetic field H isothermal entropy change induced by changing H, Δs(H,T), in temperature range. uses miniaturized Peltier cells flux, with resolution about 1 μW, power regulate range from 243 K (-30 °C) 343 (+70 °C). kinetic effects due capacity measuring are taken into account simple...
The Laser Interferometer Space Antenna (LISA) is a gravitational wave detector, which aims to detect 10−20 strains in the frequency range from 0.1 mHz Hz. It constellation of three spacecrafts, an equilateral triangle with side length m, where interferometry monitors spacecraft distances. Aberrations and jitter wavefront sent by next combine cause measurement noise. paper investigates analytically this coupling, including beam clipping far-field propagation, develops criteria for assessment...
The observation of neutron interference using a triple Laue interferometer formed by two separate crystals opens the way to construction and operation skew-symmetric interferometers with extended arm separation length. specifications necessary for their successful are investigated here: most importantly, how manufacturing tolerance crystal alignments impact visibility. In contrast previous studies, both incoherent sources three-dimensional considered. It is found that, Gaussian Schell model...
An additional value of the Avogadro constant was obtained by counting atoms in isotopically enriched Si spheres. With respect to previous determination, spheres were etched and repolished eliminate metal contaminations improve roundness. In addition, all input quantities -- molar mass, lattice parameter, volume remeasured aiming at a smaller uncertainty. order make values given Refs.\ 1 2 usable for least squares adjustment, we report about estimate their correlation.
The Laser Interferometer Space Antenna aims to measure picometer changes of the 2.5 × 106 km sides a triangular constellation satellites. Each spacecraft hosts two telescopes that simultaneously transmit and receive laser beams measuring arms by heterodyning received wavefronts with local references. We report an end-to-end investigation measurement noise due interaction between telescope jitters wavefront aberrations. With provisional design parameters, achieve targeted sensitivity...
We developed a calorimetric technique to measure the isothermal magnetocaloric entropy change. The method consists in use of Peltier cells as heat flow sensor and pump at same time. In this paper, we describe setup, constitutive equations cell actuator, calibration procedure. is used keep sample when magnetic field changed. temperature difference between thermal reservoir kept by digital control within 5 mK for rate 20 mT s(-1). flux sensitivity around 1 microW. With method, it possible...
The Laser Interferometer Space Antenna is a foreseen space-based gravitational wave detector, which aims to detect 10^20 strains in the frequency range from 0.1 mHz 1 Hz. It triangular constellation of three spacecraft, with equal sides 2,5 x 10^9 m, where every spacecraft hosts pair telescopes that simultaneously transmit and receive laser beams measuring arms by heterodyning received wavefronts local references. Due jitters, interfering (received local) become misaligned. We investigate...
MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 586:217-232 (2018) - DOI: https://doi.org/10.3354/meps12396 Estimating distribution and relative density of satellite-tagged loggerhead sea turtles using geostatistical mixed effects models Megan V. Winton1,*, Gavin Fay1, Heather L. Haas2, Michael Arendt3, Susan Barco4, C. James5, Christopher Sasso6, Ronald...
The role of hysteresis on materials with giant magnetocaloric effect (GMCE) was pointed out by comparing isothermal entropy change measured a Ni55Mn20Ga25 single crystal presenting first order magnetostructural phase transition. is determined laboratory Peltier calorimeter magnetic field up to 2T. measurements performed have allowed compare the in partial or complete transitions induced temperature field, respectively. sequence and affects dramatically observed MCE demonstrating that control...
Depending on the starting equilibrium temperature, application of a magnetic field sample Ni–Mn–Sn produces heating or cooling during adiabatic experiments. The competition between endothermal and exothermal effects is observed close to martensite-to-austenite magnetostructural phase transition. A model assuming coexistence two phases dependence their volume allows compute evolution entropy heat capacity correct fitting results suggests that field-induced reduction transition temperature...
In this paper we study the specific heat under magnetic field cp(Ha,T) and induced isothermal entropy change Δs(Ha,T) of Er2Fe14B by direct calorimetry measurements. We find that spin reorientation temperature is TSR=322.8±0.1 K Δs=0.735±0.005Jkg-1K-1. The measured data are interpreted a model magnetization process taking into account temperature-dependent uniaxial anisotropy constant K1(T), energy, effect demagnetizing field. able to describe essential features in terms reversible rotation...
The dynamic magnetocaloric effect in La(FexCoySi1-x-y)13 with x=0.9 and low Co content of y=0.015 was analysed by calorimetric measurements at constant magnetic field temperature as well magnetisation relaxation measurements. It is shown that the rate dependence measurement, which leads to an increased entropy hysteresis increasing driving force (temperature or field), can be mainly attributed a thermal contact resistance R between sample bath measurement setup.
The magnetostriction measurements of almost stoichiometric single crystalline Ni_2MnGa compound with T_m<T_C (T_m and T_C are the martensitic ferromagnetic transformation temperatures respectively) at constant have been performed in a temperature range 100--400 K. resulted evolution magnetostrain, \varepsilon, two extremums caused by soft mode condensation transformation. Magnetic field induced strain 0.4% In turn, dilatometric along [100] under magnetic (either or cyclic) led to 1.5%...