773 research outputs found
Long-term starin monitoring data of jacket-type offshore structure for tidal current power generation under severe tidal current environments
Structural strain responses of the jacket-type Uldolmok tidal current power plant structure under severe\ud
tidal environments were analyzed using long-term measurement data from construction to normal operation. From the\ud
measured data during construction, it was found that there were significant changes in strain responses at the steps of\ud
jacket lifting, weight-block loading, pile ejection and insertion. Strains due to permanent and tidal current loads were\ud
analyzed during removal work on one among six jacket legs, and it was found that the strains due to permanent load\ud
were much significantly changed after removal of on jacket leg. From the measurement data during normal operation, it\ud
was observed that strain responses were obviously fluctuated with M2 and M4 tidal periods and also with relatively\ud
short period of about 11 min due to the peculiar tidal characteristics in the Uldolmok strait
Pair production of neutralinos via gluon-gluon collisions
The production of a neutralino pair via gluon-gluon fusion is studied in the
minimal supersymmetric model(MSSM) at proton-proton colliders. The numerical
analysis of their production rates are carried out in the mSUGRA scenario. The
results show that this cross section may reach about 80 femto barn for
pair production and 23 femto barn
for pair production with suitable
input parameters at the future LHC collider. It shows that this loop mediated
process can be competitive with the quark-antiquark annihilation process at the
LHC.Comment: LaTex file, l4 pages, 5 EPS figure
Exclusion Statistics of Quasiparticles in Condensed States of Composite Fermion Excitations
The exclusion statistics of quasiparticles is found at any level of the
hierarchy of condensed states of composite fermion excitations (for which
experimental indications have recently been found). The hierarchy of condensed
states of excitations in boson Jain states is introduced and the statistics of
quasiparticles is found. The quantum Hall states of charged -anyons
( -- the exclusion statistics parameter) can be described as
incompressible states of -anyons ( -- an even number).Comment: 4 page
Complete genome sequence of an emergent recombinant GII. P16-GII. 2 norovirus strain associated with an epidemic spread in the winter of 2016-2017 in Hong Kong, China
A new recombinant norovirus, GII.P16-GII.2, emerged in the winter of 2016-2017. Here, we report the complete genome of this strain (Hu/GII/HK/2016/GII.P16-GII.2/CUHK-NS-1082), which was collected from a patient hospitalized with gastroenteritis in September 2016 in Hong Kong, China, and sequenced using next-generation sequencing. This genome had a 95.2% nucleotide identity to the closest sequence in GenBank
YREC: The Yale Rotating Stellar Evolution Code
The stellar evolution code YREC is outlined with emphasis on its applications
to helio- and asteroseismology. The procedure for calculating calibrated solar
and stellar models is described. Other features of the code such as a non-local
treatment of convective core overshoot, and the implementation of a
parametrized description of turbulence in stellar models, are considered in
some detail. The code has been extensively used for other astrophysical
applications, some of which are briefly mentioned at the end of the paper.Comment: 10 pages, 2 figures, ApSS accepte
Development of cylindrical laminated methanol steam reforming microreactor with cascading metal foams as catalyst support
In this study, the cascading metal foams were used as catalyst supports for constructing a new type of cylindrical laminated methanol steam reforming microreactor for hydrogen production. The two-layer impregnation method was used to load the Cu/Zn/Al/Zr catalysts, and the ultrasonic vibration method was then employed to investigate the loading performance of metal foams with different types and thicknesses. Furthermore, the effect of the type of catalyst placement, pores per inch (PPI) and foam type on the performance of methanol steam reforming microreactor was studied by varying the gas hourly space velocity (GHSV) and reaction temperature. Compared with two other types of catalyst placement studied, the microreactor containing catalyst-loaded metal foams without clearance cascading (3 × 2) showed the highest hydrogen production performance. When the PPI of the metal foam was increased from 50 to 100, both the methanol conversion and the H2 flow rate gradually increased. Our results also showed that a microreactor with Cu foam as a catalyst support exhibits increased hydrogen production and higher stability than those of a microreactor with Ni foam
Generalized twisted modules associated to general automorphisms of a vertex operator algebra
We introduce a notion of strongly C^{\times}-graded, or equivalently,
C/Z-graded generalized g-twisted V-module associated to an automorphism g, not
necessarily of finite order, of a vertex operator algebra. We also introduce a
notion of strongly C-graded generalized g-twisted V-module if V admits an
additional C-grading compatible with g. Let V=\coprod_{n\in \Z}V_{(n)} be a
vertex operator algebra such that V_{(0)}=\C\one and V_{(n)}=0 for n<0 and let
u be an element of V of weight 1 such that L(1)u=0. Then the exponential of
2\pi \sqrt{-1} Res_{x} Y(u, x) is an automorphism g_{u} of V. In this case, a
strongly C-graded generalized g_{u}-twisted V-module is constructed from a
strongly C-graded generalized V-module with a compatible action of g_{u} by
modifying the vertex operator map for the generalized V-module using the
exponential of the negative-power part of the vertex operator Y(u, x). In
particular, we give examples of such generalized twisted modules associated to
the exponentials of some screening operators on certain vertex operator
algebras related to the triplet W-algebras. An important feature is that we
have to work with generalized (twisted) V-modules which are doubly graded by
the group C/Z or C and by generalized eigenspaces (not just eigenspaces) for
L(0), and the twisted vertex operators in general involve the logarithm of the
formal variable.Comment: Final version to appear in Comm. Math. Phys. 38 pages. References on
triplet W-algebras added, misprints corrected, and expositions revise
Electrooxidation of glucose by binder-free bimetallic Pd1Ptx/graphene aerogel/nickel foam composite electrodes with low metal loading in basic medium
Many 2D graphene-based catalysts for electrooxidation of glucose involved the use of binders and toxic reducing agents in the preparation of the electrodes, which potentially causes the masking of original activity of the electrocatalysts. In this study, a green method was developed to prepare binder-free 3D graphene aerogel/nickel foam electrodes in which bimetallic Pd-Pt NP alloy with different at% ratios were loaded on 3D graphene aerogel. The influence of Pd/Pt ratio (at%: 1:2.9, 1:1.31, 1:1.03), glucose concentration (30 mM, 75 mM, 300 mM, 500 mM) and NaOH concentration (0.1 M, 1 M) on electrooxidation of glucose were investigated. The catalytic activity of the electrodes was enhanced with increasing the Pd/Pt ratio from 1:2.9 to 1:1.03, and changing the NaOH/glucose concentration from 75 mM glucose/0.1 M NaOH to 300 mM glucose/1 M NaOH. The Pd1Pt1.03/GA/NF electrode achieved a high current density of 388.59 A g−1 under the 300 mM glucose/1 M NaOH condition. The stability of the electrodes was also evaluated over 1000 cycles. This study demonstrated that the Pd1Pt1.03/GA/NF electrode could be used as an anodic electrode in glucose-based fuel cells
Local field factors in a polarized two-dimensional electron gas
We derive approximate expressions for the static local field factors of a
spin polarized two-dimensional electron gas which smoothly interpolate between
their small- and large-wavevector asymptotic limits. For the unpolarized
electron gas, the proposed analytical expressions reproduce recent diffusion
Monte Carlo data. We find that the degree of spin polarization produces
important modifications to the local factors of the minority spins, while the
local field functions of the majority spins are less affected.Comment: 8 pages, 10 figure
Green function techniques in the treatment of quantum transport at the molecular scale
The theoretical investigation of charge (and spin) transport at nanometer
length scales requires the use of advanced and powerful techniques able to deal
with the dynamical properties of the relevant physical systems, to explicitly
include out-of-equilibrium situations typical for electrical/heat transport as
well as to take into account interaction effects in a systematic way.
Equilibrium Green function techniques and their extension to non-equilibrium
situations via the Keldysh formalism build one of the pillars of current
state-of-the-art approaches to quantum transport which have been implemented in
both model Hamiltonian formulations and first-principle methodologies. We offer
a tutorial overview of the applications of Green functions to deal with some
fundamental aspects of charge transport at the nanoscale, mainly focusing on
applications to model Hamiltonian formulations.Comment: Tutorial review, LaTeX, 129 pages, 41 figures, 300 references,
submitted to Springer series "Lecture Notes in Physics
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