3,413 research outputs found
Highest weight irreducible representations of the Lie superalgebra
Two classes of irreducible highest weight modules of the general linear Lie
superalgebra are constructed. Within each module a basis is
introduced and the transformation relations of the basis under the action of
the algebra generators are written down.Comment: 24 pages, TeX; Journ. Math. Phys. (to be published
Finite-Dimensional Representations of the Quantum Superalgebra U[gl(2/2)]: II. Nontypical representations at generic
The construction approach proposed in the previous paper Ref. 1 allows us
there and in the present paper to construct at generic deformation parameter
all finite--dimensional representations of the quantum Lie superalgebra
. The finite--dimensional -modules
constructed in Ref. 1 are either irreducible or indecomposible. If a module
is indecomposible, i.e. when the condition (4.41) in Ref. 1 does not
hold, there exists an invariant maximal submodule of , to say
, such that the factor-representation in the factor-module
is irreducible and called nontypical. Here, in this paper,
indecomposible representations and nontypical finite--dimensional
representations of the quantum Lie superalgebra are considered
and classified as their module structures are analized and the matrix elements
of all nontypical representations are written down explicitly.Comment: Latex file, 49 page
The development and application of aerodynamic uncertainties: And flight test verification for the space shuttle orbiter
The approach used in establishing the predicted aerodynamic uncertainties and the process used in applying these uncertainties during the design of the Orbiter flight control system and the entry trajectories are presented. The flight test program that was designed to verify the stability and control derivatives with a minimum of test flights is presented and a comparison of preflight predictions with preliminary flight test results is made. It is concluded that the approach used for the Orbiter is applicable to future programs where testing is limited due to time constraints or funding
Conditional quantum logic using two atomic qubits
In this paper we propose and analyze a feasible scheme where the detection of
a single scattered photon from two trapped atoms or ions performs a conditional
unitary operation on two qubits. As examples we consider the preparation of all
four Bell states, the reverse operation that is a Bell measurement, and a CNOT
gate. We study the effect of atomic motion and multiple scattering, by
evaluating Bell inequalities violations, and by calculating the CNOT gate
fidelity.Comment: 23 pages, 8 figures in 11 file
Численное моделирование тектонической и термической истории Кындалского грабена Буреинского бассейна (Дальний Восток России)
Because the endocrine disrupting effects of nonylphenol (NP) and octylphenol became evident, the degradation of long-chain alkylphenols (AP) by microorganisms was intensively studied. Most NP-degrading bacteria belong to the sphingomonads and closely related genera, while NP metabolism is not restricted to defined fungal taxa. Growth on NP and its mineralization was demonstrated for bacterial isolates, whereas ultimate degradation by fungi still remains unclear. While both bacterial and fungal degradation of short-chain AP, such as cresols, and the bacterial degradation of long-chain branched AP involves aromatic ring hydroxylation, alkyl chain oxidation and the formation of phenolic polymers seem to be preferential elimination pathways of long-chain branched AP in fungi, whereby both intracellular and extracellular oxidative enzymes may be involved. The degradation of NP by sphingomonads does not proceed via the common degradation mechanisms reported for short-chain AP, rather, via an unusual ipso-substitution mechanism. This fact underlies the peculiarity of long-chain AP such as NP isomers, which possess highly branched alkyl groups mostly containing a quaternary alpha-carbon. In addition to physicochemical parameters influencing degradation rates, this structural characteristic confers to branched isomers of NP a biodegradability different to that of the widely used linear isomer of NP. Potential biotechnological applications for the removal of AP from contaminated media and the difficulties of analysis and application inherent to the hydrophobic NP, in particular, are also discussed. The combination of bacteria and fungi, attacking NP at both the phenolic and alkylic moiety, represents a promising perspective
Polymorphism of CsGaS2 - structural characterization of a new two-dimensional polymorph and study of the phase-transition kinetics
CsGaS2-mC64 was obtained by reaction of CsN3 with stoichiometric amounts of Ga2S3 and S at elevated temperatures. The crystal structure of the air- and moisture stable compound was determined from single-crystal X-ray diffraction data. The colourless solid crystallizes in the monoclinic space group C2/c (no. 15) with the lattice parameters a = 10.5718(6) angstrom, b = 10.5708(6) angstrom, c = 16.0847(8) angstrom, ss = 99.445(4)degrees, V = 1773.1(2) angstrom(3), and Z = 16. The compound crystallizes in the TlGaSe2 structure type and features anionic layers (2)(infinity)[Ga4S84-] consisting of corner-sharing Ga4S10 supertetrahedra. At temperatures above 600 degrees C an irreversible phase-transition to CsGaS2-mC16 occurs. The phase-transition kinetics were studied using in situ high-temperature X-ray powder diffraction techniques. This transition can only be reversed by using high pressures (> 5 GPa at 500 degrees C). The compound was further characterized using Raman- and diffuse reflectance spectroscopy. Chemical bonding was analysed by DFT calculations
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