11,872 research outputs found
Thermocapillary actuation of droplets on chemically patterned surfaces by programmable microheater arrays
We have designed a microfluidic device for the actuation of liquid droplets or continuous streams on a solid surface by means of integrated microheater arrays. The microheaters provide control of the surface temperature distribution with high spatial resolution. These temperature gradients locally alter the surface tension along droplets and thin films thus propelling the liquid toward the colder regions. In combination with liquophilic and liquophobic chemical surface patterning, this device can be used as a logistic platform for the parallel and automated routing, mixing and reacting of a multitude of liquid samples, including alkanes, poly(ethylene glycol) and water
Topological Disorder Operators in Three-Dimensional Conformal Field Theory
Many abelian gauge theories in three dimensions flow to interacting conformal
field theories in the infrared. We define a new class of local operators in
these conformal field theories which are not polynomial in the fundamental
fields and create topological disorder. They can be regarded as
higher-dimensional analogues of twist and winding-state operators in free 2d
CFTs. We call them monopole operators for reasons explained in the text. The
importance of monopole operators is that in the Higgs phase, they create
Abrikosov-Nielsen-Olesen vortices. We study properties of these operators in
three-dimensional QED using large N_f expansion. In particular, we show that
monopole operators belong to representations of the conformal group whose
primaries have dimension of order N_f. We also show that monopole operators
transform non-trivially under the flavor symmetry group, with the precise
representation depending on the value of the Chern-Simons coupling.Comment: 24 pages, latex. v2: a reference to prior work has been adde
Comment on and Erratum to "Pressure of Hot QCD at Large N_f"
We repeat and correct the recent calculation of the thermodynamic potential
of hot QCD in the limit of large number N_f of fermions. The new result for the
thermal pressure turns out to agree significantly better with results obtained
from perturbation theory at small coupling. For large coupling, a nonmonotonic
behaviour is reproduced, but the pressure of the strongly coupled theory does
not exceed the free pressure as long as the Landau pole ambiguity remains
negligible numerically.Comment: 9 pages, 3 figures, JHEP3; v2: version accepted for publication in
JHEP (title changed, 1 footnote added, 1 reference updated, content otherwise
unchanged
On the origin of exponential growth in induced earthquakes in Groningen
The Groningen gas field shows exponential growth in earthquakes event counts
around a magnitude M1 with a doubling time of 6-9 years since 2001. This
behavior is identified with dimensionless curvature in land subsidence, which
has been evolving at a constant rate over the last few decades {essentially
uncorrelated to gas production.} We demonstrate our mechanism by a tabletop
crack formation experiment. The observed skewed distribution of event
magnitudes is matched by that of maxima of event clusters with a normal
distribution. It predicts about one event \,M5 per day in 2025, pointing to
increasing stress to human living conditions.Comment: 12 pages, 7 figures, to appear in Earthquakes and Structure
DEVELOPMENT OF ANALYTICAL METHOD FOR IMATINIB MESYLATE BY ULTRAVIOLET SPECTROSCOPY
Objective: A simple, selective, sensitive, specific, and spectrophotometric method has been developed for the detection of imatinib mesylate in pure form and formulations.
Methods: The analytical condition was optimized for the drug, carried out as per the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines.
Results: The drug shows absorption at 232.0 nm and obeyed beers law in the wide concentration range from 0.5 to 4.0 μg/ml. The lower limit of detection was found to be 0.331 μg/ml and the limit of quantification to be 1.004 μg/ml. The regression equation was found to be y = 0.08x. The precision of the method was found to be 99.04%±0.527% and the percentage of drug recovered by this method is 100.13%±1.375%.
Conclusion: The method is simple and suitable for determination for imatinib mesylate in pure and pharmaceutical preparation
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