30,151 research outputs found
Process of casting heavy slips Patent
Freeze casting of metal ceramic and refractory compound powders into plastic slip
Multipole Expansions of Aggregate Charge: How Far to Go?
Aggregates immersed in a plasma or radiative environment will have charge
distributed over their extended surface. Previous studies have modeled the
aggregate charge using the monopole and dipole terms of a multipole expansion,
with results indicating that the dipole-dipole interactions play an important
role in increasing the aggregation rate and altering the morphology of the
resultant aggregates. This study examines the effect that including the
quadrupole terms has on the dynamics of aggregates interacting with each other
and the confining electric fields in laboratory experiments. Results are
compared to modeling aggregates as a collection of point charges located at the
center of each spherical monomer comprising the aggregate.Comment: 6 page
Quantification of three-dimensional folding using fluvial terraces: A case study from the Mushi anticline, northern margin of the Chinese Pamir
Fold deformation in three dimensions involves shortening, uplift, and lateral growth. Fluvial terraces represent strain markers that have been widely applied to constrain a fold's shortening and uplift. For the lateral growth, however, the utility of fluvial terraces has been commonly ignored. Situated along northern margin of Chinese Pamir, the Mushi anticline preserves, along its northern flank, flights of passively deformed fluvial terraces that can be used to constrain three-dimensional folding history, especially lateral growth. The Mushi anticline is a geometrically simple fault-tip fold with a total shortening of 740?±?110?m and rock uplift of ~1300?m. Geologic and geomorphic mapping and dGPS surveys reveal that terrace surfaces perpendicular to the fold's strike display increased rotation with age, implying the fold grows by progressive limb rotation. We use a pure-shear fault-tip fold model to estimate a uniform shortening rate of 1.5?+?1.3/?0.5?mm/a and a rock-uplift rate of 2.3?+?2.1/?0.8?mm/a. Parallel to the fold's strike, longitudinal profiles of terrace surfaces also display age-dependent increases in slopes. We present a new model to distinguish lateral growth mechanisms (lateral lengthening and/or rotation above a fixed tip). This model indicates that eastward lengthening of the Mushi anticline ceased by at least ~134?ka and its lateral growth has been dominated by rotation. Our study confirms that terrace deformation along a fold's strike not only can constrain the lateral lengthening rate but can serve to quantify the magnitude and rate of lateral rotation: attributes that are commonly difficult to define when relying on other geomorphic criteria
Still flat after all these years
The Universe could be spatially flat, positively curved or negatively curved.
Each option has been popular at various times, partly affected by an
understanding that models tend to evolve away from flatness. The curvature of
the Universe is amenable to measurement, through tests such as the
determination of the angles of sufficiently large triangles. The angle
subtended by the characteristic scale on the Cosmic Microwave sky provides a
direct test, which has now been realised through a combination of exquisite
results from a number of CMB experiments.
After a long and detailed investigation, with many false clues, it seems that
the mystery of the curvature of the Universe is now solved. It's an open and
shut case: the Universe is flat.Comment: 7 pages, 2 figures, submitted to the Gravity Research Foundation
Essay Competition for 200
Majorization criterion for distillability of a bipartite quantum state
Bipartite quantum states are classified into three categories: separable
states, bound entangled states, and free entangled states. It is of great
importance to characterize these families of states for the development of
quantum information science. In this paper, I show that the separable states
and the bound entangled states have a common spectral property. More precisely,
I prove that for undistillable -- separable and bound entangled -- states, the
eigenvalue vector of the global system is majorized by that of the local
system. This result constitutes a new sufficient condition for distillability
of bipartite quantum states. This is achieved by proving that if a bipartite
quantum state satisfies the reduction criterion for distillability, then it
satisfies the majorization criterion for separability.Comment: 4 pages, no figures, REVTEX. A new lemma (Lemma 2) added. To appear
in Physical Review Letter
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