The matrix elements for the hyperfine structure of the configuration lll in SL-Kopplung are expressed as linear combinations of the electron coupling constants αli(10), αli(01), αli(12). 相似文献
Plasma presheath and saturation current collection by a planar Langmuir probe in a strong magnetic field perpendicular to the probe surface ares described with the diffusion model. The model takes into consideration the geometry of the probe, that is its size and shape, and dependence of the cross-field charged particles' transport into the effective collection region of the probe on the parallel-field transport to the probe. Experimental study of planar Langmiur probe I—V characteristics in D.C. discharge argon plasma in strong magnetic fields confirms the possibility of deriving the cross-field diffusion coefficient, D, from the measured electron satuation current. Additional dependence of the electron saturation current on the parallel-field diffusion coefficient, D, and the ion temperature, Ti, derived in the approximate Stangeby's study using the diffusion model of current collection by a planar surface (Stangeby, P. C., J. Phys. D: Appl. Phys. 15 (1982) 1007) can be eliminated with more rigorous calculation. Series of measurements on two neutral pressures and various magnetic fields gave reproducible values of D, approximately given by relation D ≈ (δn/〈n〉) kBTe/(eB). 相似文献
The inclusion complexes of p‐sulfonated calix[4, 6] arene and β‐cyclodextrin with dopamine were studied by fluorescence spectrometry in aqueous media. It was found that the fluorescence intensity of dopamine regularly decreased upon the addition of p‐sulfonated calix[4, 6] arene, on the contrary, it increased upon the addition of β‐cyclodextrin. 1H NMR spectra were applied to verify the formation of the complexes. According to the experimental results, 1:1 stoichiometry for the complexes was established and their association constants at 25°C were calculated by applying a deduced equation. Judging from the magnitude of their inclusion constants, the p‐sulfonated calix[4, 6] arene showed better inclusion capability than β‐cyclodextrin. The probable interaction mechanisms are proposed. 相似文献
Quantitative optical spectroscopy measurements of the emission spectra of the N(B2∑u,)ν′→X2∑gν″ transition (first negative system) in an Ar-N2 microwave discharge at atmospheric pressure have allowed determination of the rate coefficient of the production of N molecules in the B2 ∑u, state with vibrational level ν′ = 0. The N(B2∑u, ν′) molecules are produced by the reaction in a surface-wave-induced microwave discharge (2450 MHz) sustained in an open-ended dielectric tube. The rate coefficient K (T) has been obtained for ν′ν″ = 0 for different gas temperatures by varying the incident microwave power. The K00(T) values are between 7.10?10 and 4.10?10 cm3 s?1 for the temperature range 2500 to 3450K. 相似文献
The minimal Standard Model exhibits a nontrivial chiral U(2) symmetry if the VEV and the hypercharge splitting Δ = (y-y)/2 of right-handed leptons (quarks) in a family vanish and Q = T0 + Y independently in each helicity sector. As a generalization, we start with SU(2)L × SU(2)R × U(1)(B-L) and introduce Δ as a continuous parameter which is a measure of explicit symmetry breakdown. Values 0 ? Δ ? 1/2 take the neutral generator of the isospin ½ representation to the singlet representation, i.e. ‘deformes’ the LR representation into the minimal Standard one. The corresponding classical O(3)-breaking term is a magnetic field perpendicular to the x3-axis. A simple mapping on the fundamental Drinfeld-Jimbo q-deformed SU(2) representation is given. 相似文献
Desorption- and Reactionkinetics of the Alkaline Earth Elements Calcium and Strontium with Chlorine on a Tungsten Surface — Part I: Chemical Equilibrium of the Surface Reaction M + Cl ? MCl in the Steady State (M = Ca, Br) Utilizing positive and negative surface ionization the reaction M + Cl = MCl (M = Ca, Sr) was studied at a hot tungsten surface under steady state conditions. Comparing the results obtained either by simultaneous M- and Cl2 -exposures or by MCl2 -exposure the existence of chemical equilibrium could be confirmed for the reaction in the temperature interval 1600 K.2000 K; at higher temperatures this equilibrium can be disturbed considerably by the desorption of the reacting components. From the experimental results we obtained under conditions of chemical equilibrium the energy of dissociation of MCl-molecules in the gasphase (D = (3.9 ± 0.15) eV, D = (4.2 ± 0.15)eV) and in the case of a strong disturbance of the equilibrium the difference between the activation energies of desorption and of dissociation of MCl-molecules on the surface (? - D? = (1.6 ± 0.2) eV, ? - D? = (1.4 ± 0.2) eV). 相似文献
We study the gauged sigma model and its mirror Landau‐Ginsburg model corresponding to type IIA on the Fermat degree‐24 hypersurface in WCP 4[1,1,2,8,12] (whose blow‐up gives the smooth CY3(3,243)) away from the orbifold singularities, and its orientifold by a freely‐acting antiholomorphic involution. We derive the Picard‐Fuchs equation obeyed by the period integral as defined in [1, 2], of the parent 𝒩 = 2 type IIA theory of [3]. We obtain the Meijer's basis of solutions to the equation in the large and small complex structure limits (on the mirror Landau‐Ginsburg side) of the abovementioned Calabi‐Yau, and make some remarks about the monodromy properties associated based on [4], at the same and another MATHEMATICAlly interesting point. Based on a recently shown 𝒩 = 1 four‐dimensional triality [6] between Heterotic on the self‐mirror Calabi‐Yau CY3(11,11), M theory on and F‐theory on an elliptically fibered CY4 with the base given by CP 1 × Enriques surface, we first give a heuristic argument that there can be no superpotential generated in the orientifold of of CY3(3,243), and then explicitly verify the same using mirror symmetry formulation of [2] for the abovementioned hypersurface away from its orbifold singularities. We then discuss briefly the sigma model and the mirror Landau‐Ginsburg model corresponding to the resolved Calabi‐Yau as well. 相似文献
Due to the high anisotropy of the dc conductivity (σ|/σ⊥ ≈ 104) the organic conductor (fluoranthene)2X can be regarded as a model system for studying the Peierls instability in quasi-one-dimensional systems. The temperature dependence of the dc conductivity σ| (T) along the highly conducting crystal axis exhibits the typical behaviour of a quasi-one-dimensional metal with a Peierls transition at about 180 K to a charge density wave (CDW) ground state. As expected for a highly one-dimensional conductor the exact transition temperature depends on three-dimensional coupling effects and therefore on the size of the counterion X? = PF, AsF, SbF. Above the Peierls transition σ| (T) can be described quantitatively within a model of CDW fluctuations leading to a pseudo gap in the electronic density of states. Below, the existence of a real energy gap at the Fermi level with a BCS-like temperature dependence determines the charge transport over more than eight orders of magnitude in the electrical resistance. For the intrinsic energy gaps 2 Δ (0), which characterize the ground state of the Peierls semiconductor, values of 120-180 meV have been found for different crystals. 相似文献