60 research outputs found
Certification of the Specific Micropore Volume and the Median Micropore Width of Two Microporous Reference Materials According to Draft-DIN 66135-4, BCR-704, BCR-705.
Abstract not availableJRC.D-Institute for Reference Materials and Measurements (Geel
Elasticity and magnetocaloric effect in MnFeSi
The room temperature magnetocaloric material MnFe4Si3 was investigated with nuclear inelastic scattering (NIS) and resonant ultrasound spectroscopy (RUS) at different temperatures and applied magnetic fields in order to assess the influence of the magnetic transition and the magnetocaloric effect on lattice dynamics. The NIS data give access to phonons with energies above 3 meV, whereas RUS probes the elasticity of the material in the MHz frequency range and thus low-energy, ∼ neV, phonon modes. A significant influence of the magnetic transition on the lattice dynamics is observed only in the low-energy, long-wavelength limit. MnFe4Si3 and other compounds in the Mn5−xFexSi3 series were also investigated with vibrating sample magnetometry, resistivity measurements, and Mössbauer spectroscopy in order to study the magnetic transitions and to complement the results obtained on the lattice dynamic
Hyperfine interactions in and lattice parameters of pyrochlore and defect fluorite
Pyrochlore and defect fluorite (Eu1−xNdx)2Zr2O7 compounds (x = 0, 0.5 and 0.75) synthesized by a wet chemicalapproach were investigated using temperature dependent high energy X-ray diffraction as well as 151Eu Mössbauerspectroscopy. Diffraction data reveals an increase in lattice parameter with increasing Nd content, an increase thatis disproportionally large between x = 0.5 and 0.75. The 151Eu Mössbauer spectral parameters, i.e. isomer shift andquadrupole splitting, fall in separate regions for pyrochlore and defect fluorite type compounds. Between 80 - 350 K,the impact of the order-disorder, i.e. pyrochlore to defect fluorite, transition on isomer shift and quadrupole splittingis found to exceed the one due to lattice expansion
On the terms mass and weight
A short survey is given on mass units and recommendations on the proper use of the notations mass and weight.Whereas mass is an inertial physical quantity in classical mechanics, weight is a force due to the gravitational field and depending on the geographic situation
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