3,845 research outputs found
(9S,13R,14S)-7,8-Didehydro-4-(4-iodobenzyloxy)-3,7-dimethoxy-17-methylmorphinan-6-one monohydrate
In the title compound, C26H28INO4·H2O, benzene rings are inclined at a dihedral angle of 69.9 (1)°. The N-containing ring exhibits a chair conformation, while the other rings approximate to envelope conformations. In the crystal, the uncoordinated water molecule forms intermolecular O—H⋯O and O—H⋯N hydrogen bonds
Strong decays of the as a fully-strange tetraquark state
We study strong decays of the , along with its possible partner
, as two fully-strange tetraquark states of . We
consider seven decay channels: , , , , , , and
. Some of these channels are kinematically possible, and
we calculate their relative branching ratios through the Fierz rearrangement.
Future experimental measurements on these ratios can be useful in determining
the nature of the and . The has been
observed in the , , and channels,
and we propose to further examine it in the channel. Evidences
of the have been observed in the channel, and we
propose to verify whether this structure exists or not in the ,
, , and channels.Comment: 10 pages, 3 figures, 1 table, suggestions and comments are welcom
A semi-analytical method for the dynamic analysis of cylindrical shells with arbitrary boundaries
The dynamic behavior of cylindrical shells with arbitrary boundaries is studied in this paper. Love's shell theory and Hamilton's principle are employed to derive the motion equations for cylindrical shells. A semi-analytical methodology, which incorporates Durbin's inverse Laplace transform, differential quadrature method and Fourier series expansion technique, is proposed to investigate this phenomenon. The use of the differential quadrature method provides a solution in terms of the axial direction whereas the use of Durbin's numerical inversion method generates a solution in the time domain. Comparison of calculated frequency parameters to that derived from the literature illustrates the effectiveness of the method. Specifically, convergence tests indicate that the present approach has a rapid convergence, the time-history response and the Navier's solution are in great agreement. Comparisons between time-history responses derived by two shell theories show that the results fit well with each other when the thickness-radius ratios are small enough. An analysis of the influences of boundaries on the time-history response of cylindrical shells indicates that the peak displacement is closely related to the degrees of freedom of boundaries. The influences of the length-radius ratios and the thickness-radius ratios on the peak displacement are further investigated
Pair Production of Charged Higgs Bosons from Bottom-Quark Fusion
For very large values of , charged Higgs boson pair production at
the Large Hadron Collider (LHC) from the scattering of two bottom quarks can
proceed dominantly. We investigated the cross sections of charged Higgs boson
pair production via the subprocess at the LHC including
the next-to-leading order (NLO) QCD corrections in the minimal supersymmetric
standard model (MSSM). We find that the NLO QCD corrections can significantly
reduce the dependence of the cross sections on the renormalization and
factorization scales.Comment: small changes are mad
(9S,13R,14S)-7,8-Didehydro-4-(4-fluorobenzyloxy)-3,7-dimethoxy-17-methylmorphinan-6-one sesquihydrate
In the title sinomenine derivative, C26H28FNO4·1.5H2O, the dihedral angle between the two aromatic rings is 55.32 (6)°. The N-containing ring has an approximate chair conformation, while other two rings have approximate envelope and half-chair conformations. One water molecule is located on a twofold symmetry axis. In the crystal, the water molecules form O—H⋯O and O—H⋯N hydrogen bonds, bridging symmetry-related main molecules
Specular Andreev Reflection in Inversion-symmetric Weyl-semimetals
The electron-hole conversion at the normal-metal superconductor interface in
inversion-symmetric Weyl semimetals is investigated with an effective two-band
model. We find that the specular Andreev reflection of Weyl fermions has two
unusual features. The Andreev conductance for s-wave BCS pairing states is
anisotropic, depending on the angle between the line connecting a pair of Weyl
points and the normal of the junction, due to opposite chirality carried by the
paired electrons. For the Fulde-Ferrell-Larkin-Ovchinnikov pairing states, the
Andreev reflection spectrum is isotropic and is independent of the finite
momentum of the Cooper pairs
Study on Spinnability of PP/PU Blends and Preparation of PP/PU Bi-component Melt Blown Nonwovens
Melt blown polymer blends offers a good way to combine two polymers in the same fiber generating nonwovens with new and novel properties. In this study, polypropylene (PP) and polyurethane (PU) were blended to prepare PP/PU bicomponent melt blown nonwovens. The spinnability of PP/PU composites was investigated and PP/PU bi-component nonwovens with compositions of 95/5, 90/10, 80/20 and 70/30 were prepared by using the melt blowing technique. The melt blown fibers exhibited a ‘sea-island’ structure with PP as the continuous phase and PU as the dispersed phase. When the content of PU in the blend was above 40 %, PP/PU melt blown nonwovens could not be produced due to fiber breaking. For PP/PU (90/10) nonwovens, it was found that the average fiber diameter decreased with increasing die to collector (DCD) and elevated hot air pressure
The effects of the little Higgs models on production via collision at linear colliders
In the frameworks of the littlest Higgs() model and its extension with
T-parity(), we studied the associated production process at the future linear colliders
up to QCD next-to-leading order. We present the regions of
parameter space in which the and effects can and cannot be
discovered with the criteria assumed in this paper. The production rates of
process in different photon polarization
collision modes are also discussed. We conclude that one could observe the
effects contributed by the or model on the cross section for the
process in a reasonable parameter
space, or might put more stringent constraints on the / parameters in
the future experiments at linear colliders.Comment: 22 pages, 25 figures, version to appear in Phys. Rev.
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