94,772 research outputs found
Investigation on influential factors on chloride concentration index of cement-based materials by pore solution expression method
In this study, the effects of different factors on chloride concentration index (N-c) of cement paste were studied. The factors including chloride concentration in soaking solution, slag replacement, external applied voltage and cation ions of soaking solution were all studied from the electrical double layer (EDL) properties point of view. Zeta potential and proton Nuclear Magnetic Resonance (H-1 NMR) measurements were conducted to investigate the properties of electrical double layer for cement paste specimens and their effects on the value of chloride concentration index. The results showed that these factors all impacted effects on chloride concentration in electrical double layer and chloride concentration index. The properties of electrical double layer including chloride distribution and thickness of electrical double layer mainly controlled the phenomenon of "chloride concentrate" and value of chloride concentration index. As the increase of zeta potential and electrical double layer thickness, the content of chloride ions in electrical double layer and the value of chloride concentration index gradually increased. (C) 2019 Elsevier Ltd. All rights reserved
Theory of time-resolved spectral function in high-temperature superconductors with bosonic modes
We develop a three-temperature model to simulate the time dependence of
electron and phonon temperatures in high-temperature superconductors displaying
strong anistropic electron-phonon coupling. This model not only takes the
tight-binding band structure into account, but also is valid in superconducting
state. Based on this model, we calculate the time-resolved spectral function
via the double-time Green's functions. We find that the dip-hump structure
evolves with the time delay. More interestingly, new phononic structures are
obtained when the phonons are excited by a laser field. This signature may
serve as a direct evidence for electron-vibration mode coupling.Comment: 5 pages, 3 figure
Extended staggered-flux phases in two-dimensional lattices
Based on the so called - model in two-dimensional (2D) lattices, we
investigate the stabilities of a class of extended staggered-flux (SF) phases
(which are the extensions of the SF phase to
generalized spatial periods) against the Fermi-liquid phase. Surprisingly, when
away from the nesting electron filling, some extended-SF phases take over the
dominant SF phase (the SF phase for the square
lattice, a SF phase for the triangular one), compete with the
Fermi-liquid phase in nontrivial patterns, and still occupy significant space
in the phase diagram through the advantage in the total electronic kinetic
energies. The results can be termed as the generalized Perierls
orbital-antiferromagnetic instabilities of the Fermi-liquid phase in 2D
lattice-electron models.Comment: 5 pages, 5 figure
OOGAN: Disentangling GAN with One-Hot Sampling and Orthogonal Regularization
Exploring the potential of GANs for unsupervised disentanglement learning,
this paper proposes a novel GAN-based disentanglement framework with One-Hot
Sampling and Orthogonal Regularization (OOGAN). While previous works mostly
attempt to tackle disentanglement learning through VAE and seek to implicitly
minimize the Total Correlation (TC) objective with various sorts of
approximation methods, we show that GANs have a natural advantage in
disentangling with an alternating latent variable (noise) sampling method that
is straightforward and robust. Furthermore, we provide a brand-new perspective
on designing the structure of the generator and discriminator, demonstrating
that a minor structural change and an orthogonal regularization on model
weights entails an improved disentanglement. Instead of experimenting on simple
toy datasets, we conduct experiments on higher-resolution images and show that
OOGAN greatly pushes the boundary of unsupervised disentanglement.Comment: AAAI 202
A discrete chemo-dynamical model of the dwarf spheroidal galaxy Sculptor: mass profile, velocity anisotropy and internal rotation
We present a new discrete chemo-dynamical axisymmetric modeling technique,
which we apply to the dwarf spheroidal galaxy Sculptor. The major improvement
over previous Jeans models is that realistic chemical distributions are
included directly in the dynamical modelling of the discrete data. This avoids
loss of information due to spatial binning and eliminates the need for hard
cuts to remove contaminants and to separate stars based on their chemical
properties. Using a combined likelihood in position, metallicity and
kinematics, we find that our models naturally separate Sculptor stars into a
metal-rich and a metal-poor population. Allowing for non-spherical symmetry,
our approach provides a central slope of the dark matter density of . The metal-rich population is nearly isotropic (with
) while the metal-poor population is tangentially
anisotropic (with ) around the half light radius
of kpc. A weak internal rotation of the metal-rich population is
revealed with . We run tests using mock data
to show that a discrete dataset with stars is required to
distinguish between a core () and cusp (), and to
constrain the possible internal rotation to better than confidence
with our model. We conclude that our discrete chemo-dynamical modelling
technique provides a flexible and powerful tool to robustly constrain the
internal dynamics of multiple populations, and the total mass distribution in a
stellar system.Comment: Accepted by MNRA
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