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1.
Non-Hermitian but -symmetrized spherically-separable Dirac and Schr?dinger Hamiltonians are considered. It is observed that the descendant Hamiltonians H r , H θ , and H φ play essential roles and offer some “user-feriendly” options as to which one (or ones) of them is (or are) non-Hermitian. Considering a -symmetrized H φ , we have shown that the conventional Dirac (relativistic) and Schr?dinger (non-relativistic) energy eigenvalues are recoverable. We have also witnessed an unavoidable change in the azimuthal part of the general wavefunction. Moreover, setting a possible interaction V(θ)≠0 in the descendant Hamiltonian H θ would manifest a change in the angular θ-dependent part of the general solution too. Whilst some -symmetrized H φ Hamiltonians are considered, a recipe to keep the regular magnetic quantum number m, as defined in the regular traditional Hermitian settings, is suggested. Hamiltonians possess properties similar to the -symmetric ones (here the non-Hermitian -symmetric Hamiltonians) are nicknamed as pseudo- -symmetric.  相似文献   

2.
The coupling between non-gray radiation heat transfer and convection-conduction heat transfer is studied. The spectral line weighted sum of gray gases model (slw) is used to account for non-gray radiation properties. The aim of this work is to analyze the influence of the different approaches used when calculating the parameters of the slw model. Such strategies include the use of optimized model coefficients to reduce the number of operations, and the interpolation of the distribution function instead of the use of mathematical correlations. Non-gray calculations are also compared to gray solutions using the Planck mean absorption coefficient, which can be also calculated with the slw model. The radiative transfer equation (rte) is solved by means of the discrete ordinates method (dom). A natural convection driven cavity is chosen to couple radiation and conduction-convection energy transfer. Several cases, with a significant variation of the ratio between radiation to convection heat transfer, as well as the ratio between radiation to conduction heat transfer, are discussed.  相似文献   

3.
4.
Matching for a wavefunction the WKB expansion at large distances and Taylor expansion at small distances leads to a compact, few-parametric uniform approximation found in Turbiner and Olivares-Pilon (2011). The ten low-lying eigenstates of H2+ of the quantum numbers (n,m,Λ,±)(n,m,Λ,±)  with n=m=0n=m=0 at Λ=0,1,2Λ=0,1,2, with n=1n=1, m=0m=0 and n=0n=0, m=1m=1 at Λ=0Λ=0 of both parities are explored for all interproton distances RR. For all these states this approximation provides the relative accuracy ?10−5?105 (not less than 5 s.d.) locally, for any real coordinate xx in eigenfunctions, when for total energy E(R)E(R) it gives 10-11 s.d. for R∈[0,50]R[0,50]  a.u. Corrections to the approximation are evaluated in the specially-designed, convergent perturbation theory. Separation constants are found with not less than 8 s.d. The oscillator strength for the electric dipole transitions E1E1 is calculated with not less than 6 s.d. A dramatic dip in the E1E1 oscillator strength f1sσg−3pσuf1sσg3pσu at R∼ReqRReq is observed. The magnetic dipole and electric quadrupole transitions are calculated for the first time with not less than 6 s.d. in oscillator strength. For two lowest states (0,0,0,±)(0,0,0,±) (or, equivalently, 1sσg1sσg and 2pσu2pσu states) the potential curves are checked and confirmed in the Lagrange mesh method within 12 s.d. Based on them the Energy Gap between 1sσg1sσg and 2pσu2pσu potential curves is approximated with modified Pade Re−R[Pade(8/7)](R)ReR[Pade(8/7)](R) with not less than 4-5 figures at R∈[0,40]R[0,40] a.u. Sum of potential curves E1sσg+E2pσuE1sσg+E2pσu is approximated by Pade 1/R[Pade(5/8)](R)1/R[Pade(5/8)](R) in R∈[0,40]R[0,40] a.u. with not less than 3-4 figures.  相似文献   

5.
This paper describes a Linux-based OS framework for integrating the FLUKA Monte Carlo software (currently distributed only for Linux) into a CD-ROM, resulting in a complete environment for a scientist to edit, link and run FLUKA routines—without the need to install a UNIX/Linux operating system. The building process includes generating from scratch a complete operating system distribution which will, when operative, build all necessary components for successful operation of FLUKA software and libraries.Various source packages, as well as the latest kernel sources, are freely available from the Internet. These sources are used to create a functioning Linux system that integrates several core utilities in line with the main idea—enabling FLUKA to act as if it was running under a popular Linux distribution or even a proprietary UNIX workstation.On boot-up a file system will be created and the contents from the CD will be uncompressed and completely loaded into RAM—after which the presence of the CD is no longer necessary, and could be removed for use on a second computer. The system can operate on any i386 PC as long as it can boot from a CD.  相似文献   

6.
A new method to determine tropisetron hydrochloride with l-tryptophan in the medium with pH=9.0 was studied, which is based on the fluorescence quenching effect of tropisetron hydrochloride on l-tryptophan. The fluorescence quenching mechanism and various factors influencing fluorescence quenching were discussed. Under the optimum conditions, the linear range and detection limit were 0.03-12.0 and 0.01 μg/mL (correlation coefficient r=0.9970), respectively. The calibration curve equation was ΔF=6.17+12.56 C (μg/mL). RSD was 3.4% (c=4.0 μg/mL, n=5); the detection limit estimated (S/N=3) was 0.01 μg/mL. The proposed method had been successfully applied to determine tropisetron hydrochloride in real samples and the obtained results were in good agreement with the results of the official method.  相似文献   

7.
We present selected recent results of multi-hadron correlation measurements in azimuth and pseudorapidity at intermediate and high p T in Au+Au collisions at , from the STAR experiment at RHIC. At intermediate p T , measurements are presented that attempt to determine the origin of the associated near-side (small Δφ) yield at large pseudo-rapidity difference Δη that is found to be present in heavy ion collisions. In addition, results are reported on new multi-hadron correlation measures at high-p T that use di-hadron triggers and multi-hadron cluster triggers with the goal to constrain the underlying jet kinematics better than in the existing measurements of inclusive spectra and di-hadron correlations.  相似文献   

8.
9.
Up to now, synthetic polymers and biomacromolecules have been grafted or assembled onto the convex surface of carbon nanotubes (CNTs) via covalent bonds or chemisorptions. In this research, poly(l-lactide-co--caprolactone)-functionalized multiwalled carbon nanotubes (MWCNT-OH-g-PCLA)s are synthesized by in situ ring-opening copolymerization of l-lactide (LA) and -caprolactone (CL) using stannous octanoate and hydroxylated MWCNTs (MWCNT-OHs) as the initiating system. The pristine MWCNTs are modified to possess carboxyl groups and then hydroxyl groups. MWCNT-OHs are used as coinitiators to polymerize LA and CL by the surface-initiated ring-opening polymerization. The FT-IR spectra, SEM and TEM micrographs revealed that the PCLA grafted form the sidewall of MWCNTs strongly. The TGA analysis indicates that about 75 wt% of functionalized MWCNTs with PCLA belongs to grafted PCLA and the remaining 25 wt% to the initial MWCNT-OH.  相似文献   

10.
In the framework of the quark–gluon string model we calculate the inclusive spectra of secondaries produced in d+Au collisions at intermediate (CERN SPS) and at much higher (RHIC) energies. The results of numerical calculations at intermediate energies are in reasonable agreement with the data. At RHIC energies numerically large inelastic screening corrections (percolation effects) should be accounted for in the calculations. We extract these effects from the existing experimental data of RHIC on minimum-bias and central d+Au collisions. The predictions for p+Au interactions at LHC energy are also given.  相似文献   

11.
We investigate the elastic properties of model composites, consisting in a dispersion of nonlinear (spherical or cylindrical) inhomogeneities into a linear solid matrix. Both phases are considered isotropic. Under the simplifying hypotheses of small deformation for the material body and of small volume fraction of the embedded phase, we develop a homogenization procedure based on the Eshelby theory, aimed at describing nonlinear features. We obtain the bulk and shear moduli and Landau coefficients of the overall material in terms of the elastic behavior of the constituents and of their volume fractions. The mixing laws for the nonlinear properties describe a complex scenario where possible strong amplifications of the nonlinearities may arise in some given conditions.  相似文献   

12.
The dissociative photoionization mechanism of l-menthone has been investigated with photoionization mass spectrometry using synchrotron radiation. The adiabatic ionization energy (IE) of l-menthone and the appearance energies (AE) of its major fragment ions C9H15O+, C9H17+, C8H16+, C7H11O+, C6H10O+, C6H9O+, C5H8O+, C5H10+, C4H6O+, C5H9+, C4H8+, C4H7+, C3H7+, C3H6+, C2H2O+, and CH3+ are determined with their photoionization efficiency (PIE) spectra in the photon energy region of ∼8−15.5 eV. Breakdown diagrams identifying the major products are presented. Dissociative photoionization channels for formation of these fragment ions are proposed based on comparison of determined experimental appearance energies and energies predicted with the DFT calculations. According to our results, the experimental dissociation energies are in fair agreement with the theoretical values of the possible photodissociation channels of C10H18O.  相似文献   

13.
l-cysteine capped CdTe quantum dots (QDs) were prepared in aqueous solution by a simple and efficient method, showing many advantages such as short synthesis period, the broaden range of starting pH value and the wide fluorescence emission wavelength range. A novel purification process was designed to remove excess Cd2+ which has potential cytotoxicity for bio-analysis. Three-dimensional fluorescence charts of pre- and post-purification showed that the purified QDs were of better luminescent performance. The prepared QDs were of cubic crystal structure with an average size of 2-6 nm, which were characterized by XRD and HRTEM. It is confirmed by IR spectra that the l-cysteine ligands were conjugated with CdTe cores via covalent bond. The degenerate fluorescence of QDs can be self-recovered in the presence of l-cysteine without other processing steps.  相似文献   

14.
《Physica B: Condensed Matter》2009,404(20):3694-3697
Electron paramagnetic resonance (EPR) of VO2+ doped potassium hydrogen d-gluconate single crystals and powder have been examined at room temperature. Single crystal rotations in each of the three mutually orthogonal crystalline planes namely ac, ba and ca indicate two different VO2+ complexes. Each complex is located in different chemical environments, each environment containing two magnetically inequivalent VO2+ sites in distinct orientations occupying substitutional positions in the lattice and showing a very large angular dependence. The powder spectrum also clearly indicates four different VO2+ complexes, confirming the single crystal analysis. Crystalline field around the VO2+ ion is nearly axial. The optical absorption spectrum of VO2+ ions in the crystal lattice is also studied at room temperature. The characteristic spectrum of the VO2+ ions has two absorption bonds. The bond positions are at 17 857 and 11 235 cm-1. Spin Hamiltonian parameters and molecular orbital coefficients are calculated from the EPR and the optical data, and results are discussed.  相似文献   

15.
In this paper, the quark distribution amplitudes of 1S and 2S heavy quarkonium states are studied in terms of Gaussian-type wave functions. The transverse momenta p integrals of the formulae for the decay constant are performed analytically. Then the quark distribution amplitudes are obtained. In addition, the ξ-moments are also calculated. After fixing the relevant parameters appearing in the quark distribution amplitude, the curves of the quark distribution amplitude for 1S and 2S heavy quarkonium states are plotted. Finally, the numerical results of this approach are compared with the other theoretical predictions.  相似文献   

16.
In a recent paper we proposed a decompositioning method to compute scattering by aggregated cylindrical fibres using a multiple scattering T-matrix approach. In this paper we extend this approach to scatterers lacking rotational symmetry. To investigate the capability of this method a square prism and a cube are decomposed into a number of subscatterers and scattering of the original particle shape is computed using multiple scattering. The results are validated using discrete dipole approximation (DDA).  相似文献   

17.
VO2+ doped l-alanine (C3H7NO2) single crystals and powders are examined by electron paramagnetic resonance (EPR) and optical absorption spectroscopy. Three magnetically different sites are resolved from angular variations of l-alanine single crystal EPR spectra. In some specific orientations each VO2+ line splits into three superhyperfine lines with intensities of 1:2:1 and maximum splitting value of 2.23 mT. The local symmetries of VO2+ complex sites are nearly axial. The optical absorption spectra show three bands. Spin Hamiltonian parameters are measured and molecular orbital coefficients are calculated by correlating EPR and optical absorption data for the central vanadyl ion.  相似文献   

18.
The Large Hadron Collider will allow studies of hard probes in nucleus-nucleus collisions which were not accessible at the Relativistic Heavy Ion Collider—even the study of small cross-section Z 0-tagged jets becomes possible. Going beyond the measurement of back-to-back correlations of two strongly interacting particles to measure plasma properties, we replace one side by an electromagnetic probe which propagates through the plasma undisturbed and therefore provides a measurement of the energy of the initial hard scattering. We show that at sufficiently high transverse momentum the Z 0-tagged jets originate predominately from the fragmentation of quarks and anti-quarks while gluon jets are suppressed. We propose to use lepton-pair tagged jets to study medium-induced partonic energy loss and to measure in-medium parton fragmentation functions to determine the opacity of the quark gluon plasma.  相似文献   

19.
F.A. Dolan   《Nuclear Physics B》2008,790(3):432-464
The free field partition function for a generic U(N) gauge theory, where the fundamental fields transform in the adjoint representation, is analysed in terms of symmetric polynomial techniques. It is shown by these means how this is related to the cycle polynomial for the symmetric group and how the large N result may be easily recovered. Higher order corrections for finite N are also discussed in terms of symmetric group characters. For finite N, the partition function involving a single bosonic fundamental field is recovered and explicit counting of multi-trace quarter BPS operators in free super-Yang–Mills discussed, including a general result for large N. The partition function for quarter BPS operators in the chiral ring of super-Yang–Mills is analysed in terms of plane partitions. Asymptotic counting of BPS primary operators with differing R-symmetry charges is discussed in both free super-Yang–Mills and in the chiral ring. Also, general and explicit expressions are derived for SU(2) gauge theory partition functions, when the fundamental fields transform in the adjoint, for free field theory.  相似文献   

20.
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