67 research outputs found
Impact of surface roughness on diffusion of confined fluids
Using event-driven molecular dynamics simulations, we quantify how the self
diffusivity of confined hard-sphere fluids depends on the nature of the
confining boundaries. We explore systems with featureless confining boundaries
that treat particle-boundary collisions in different ways and also various
types of physically (i.e., geometrically) rough boundaries. We show that, for
moderately dense fluids, the ratio of the self diffusivity of a rough wall
system to that of an appropriate smooth-wall reference system is a linear
function of the reciprocal wall separation, with the slope depending on the
nature of the roughness. We also discuss some simple practical ways to use this
information to predict confined hard-sphere fluid behavior in different
rough-wall systems
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
High Energy X-ray and Neutron Scattering on Bi2Te3 Nanowires, Nanocomposites, and Bulk Materials
IR specular reflectance studies on rough-surfaced solids and on layered systems with nonuniform interfaces: Optical simulations
Mechanochemical Synthesis of Metal Organic Frameworks A Fast and Facile Approach toward Quantitative Yields and High Specific Surface Areas
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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