298 research outputs found
Optimized extraction of soluble defatted rice bran fiber and its application for microencapsulation of fish oil
Defatted rice bran (DRB) is a byproduct of rice milling and rice bran oil extraction. Soluble rice bran fiber (SRBF) extracted from defatted rice bran is known for its antioxidant activity and hypocholesterolemic effects in human, while purified menhaden oil (PMO) is a good source of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The goal of the study was to estimate optimum extraction conditions to extract SRBF from DRB, develop a cost effective method to purify SRBF and produce microencapsulated PMO with SRBF. The response surface methodology showed that an estimated optimum yield of SRBF (7.89%) could be extracted from DRB with 3% Ca(OH)2 solution to DRB ratio 29.75:1 and stirred for 1 hr at 84oC and also Ca(OH)2 solution concentration was the most effective factor among the conditions used to extract SRBF. Our study showed that conventional processing steps, such as dialysis and alcohol precipitation, for removing mineral and monosaccharides and other small molecules from SRBF, could be replaced with the ultrafiltration technology. The ultrafiltration for purifying SRBF solution at 100 kPa with 10 kDa MWCO membrane required less time than filtering the solution at the same pressure with 1 and 5 kDa MWCO membranes. The estimated microencapsulated PMO with SRBF powder (MFMO) production rate using spray dryer was 3.45 * 10-5 kg dry solids/s and was higher than the actual production rate 2.31 * 10-5 kg dry solids/s. The energy required to increase the inlet ambient air temperature from 27.1 to 180 oC and evaporation rate for spray drying the emulsion was 2.78 kJ/s and 7.8 * 10-3 kg water/s, respectively. EPA and DHA contents of MFMO were 11.52% and 4.51%, respectively. The particle size of 90% MFMO ranged from 8 to 62 um, and the volume-length diameter of MFMO was 28.5 um. The study demonstrated that optimum extraction conditions for extracting SRBF from DRB could be achieved through the response surface methodology, conventional purification steps of SRBF including dialysis and alcohol precipitation could be replaced with ultrafiltration technology, and the MFMO could be provided with potential health benefits for humans
Anyon exclusions statistics on surfaces with gapped boundaries
An anyon exclusion statistics, which generalizes the Bose-Einstein and
Fermi-Dirac statistics of bosons and fermions, was proposed by Haldane[1]. The
relevant past studies had considered only anyon systems without any physical
boundary but boundaries often appear in real-life materials. When fusion of
anyons is involved, certain `pseudo-species' anyons appear in the exotic
statistical weights of non-Abelian anyon systems; however, the meaning and
significance of pseudo-species remains an open problem. In this paper, we
propose an extended anyon exclusion statistics on surfaces with gapped
boundaries, introducing mutual exclusion statistics between anyons as well as
the boundary components. Motivated by Refs. [2, 3], we present a formula for
the statistical weight of many-anyon states obeying the proposed statistics. We
develop a systematic basis construction for non-Abelian anyons on any Riemann
surfaces with gapped boundaries. From the basis construction, we have a
standard way to read off a canonical set of statistics parameters and hence
write down the extended statistical weight of the anyon system being studied.
The basis construction reveals the meaning of pseudo-species. A pseudo-species
has different `excitation' modes, each corresponding to an anyon species. The
`excitation' modes of pseudo-species corresponds to good quantum numbers of
subsystems of a non-Abelian anyon system. This is important because often
(e.g., in topological quantum computing) we may be concerned about only the
entanglement between such subsystems.Comment: 36 pages, 14 figure
Boundary Hamiltonian theory for gapped topological phases on an open surface
In this paper we propose a Hamiltonian approach to gapped topological phases
on an open surface with boundary. Our setting is an extension of the Levin-Wen
model to a 2d graph on the open surface, whose boundary is part of the graph.
We systematically construct a series of boundary Hamiltonians such that each of
them, when combined with the usual Levin-Wen bulk Hamiltonian, gives rise to a
gapped energy spectrum which is topologically protected; and the corresponding
wave functions are robust under changes of the underlying graph that maintain
the spatial topology of the system. We derive explicit ground-state
wavefunctions of the system and show that the boundary types are classified by
Morita-equivalent Frobenius algebras. We also construct boundary quasiparticle
creation, measuring and hopping operators. These operators allow us to
characterize the boundary quasiparticles by bimodules of Frobenius algebras.
Our approach also offers a concrete set of tools for computations. We
illustrate our approach by a few examples.Comment: 21 pages;references correcte
Gapped Boundary Theory of the Twisted Gauge Theory Model of Three-Dimensional Topological Orders
We extend the twisted gauge theory model of topological orders in three
spatial dimensions to the case where the three spaces have two dimensional
boundaries. We achieve this by systematically constructing the boundary
Hamiltonians that are compatible with the bulk Hamoltonian. Given the bulk
Hamiltonian defined by a gauge group and a four-cocycle in the
fourth cohomology group of over , a boundary Hamiltonian can be
defined by a subgroup of and a three-cochain in the third
cochain group of over . The boundary Hamiltonian to be constructed
must be gapped and invariant under the topological renormalization group flow
(via Pachner moves), leading to a generalized Frobenius condition. Given , a
solution to the generalized Frobenius condition specifies a gapped boundary
condition. We derive a closed-form formula of the ground state degeneracy of
the model on a three-cylinder, which can be naturally generalized to
three-spaces with more boundaries. We also derive the explicit ground-state
wavefunction of the model on a three-ball. The ground state degeneracy and
ground-state wavefunction are both presented solely in terms of the input data
of the model, namely,
Symmetry Fractionalized (Irrationalized) Fusion Rules and Two Domain-Wall Verlinde Formulae
We investigate interdomain excitations in composite systems of topological
orders separated by gapped domain walls. We derive two domain-wall Verlinde
formulae that relate the braiding between interdomain excitations and
domain-wall quasiparticles to the fusion rules of interdomain excitations and
the fusion rules of domain-wall quasiparticles. We show how to compute such
braiding and fusion with explicit non-Abelian examples and find that the fusion
rules of interdomain excitations are generally fractional or irrational. By
exploring the correspondence between composite systems and anyon condensation,
we uncover why such fusion rules should be called symmetry fractionalized
(irrationalized) fusion rules. Our domain-wall Verlinde formulae generalize the
Verlinde formula of a single topological order and the defect Verlinde formula
found in [C. Shen and L.-Y. Hung, Phys. Rev. Lett. 123, 051602 (2019)]. Our
results may find applications in topological quantum computing, topological
field theories, and conformal field theories.Comment: 13 pages, 7 figure
Fourier-transformed gauge theory models of three-dimensional topological orders with gapped boundaries
In this paper, we apply the method of Fourier transform and basis rewriting
developed in arXiv:1910.13441 for the two-dimensional quantum double model of
topological orders to the three-dimensional gauge theory model (with a gauge
group ) of three-dimensional topological orders. We find that the gapped
boundary condition of the gauge theory model is characterized by a Frobenius
algebra in the representation category of , which also
describes the charge splitting and condensation on the boundary. We also show
that our Fourier transform maps the three-dimensional gauge theory model with
input data to the Walker-Wang model with input data on a
trivalent lattice with dangling edges, after truncating the Hilbert space by
projecting all dangling edges to the trivial representation of . This
Fourier transform also provides a systematic construction of the gapped
boundary theory of the Walker-Wang model. This establishes a correspondence
between two types of topological field theories: the extended Dijkgraaf-Witten
and extended Crane-Yetter theories.Comment: 39 pages, 9 figure
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