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131.
An extension of the Osher upwind scheme to non-equilibrium reacting flows is presented, Owing to the presence of source terms, the Riemann problem is no longer self-similar and therefore its approximate solution becomes tedious. With simplicity in mind, a linearized approach which avoids an iterative solution is used to define the intermediate states and sonic points. The source terms are treated explicitly. Numerical computations are presented to demonstrate the feasibility, efficiency and accuracy of the proposed method. The test problems include a ZND (Zeldovich-Neumann-Doring) detonation problem for which spurious numerical solutions which propagate at mesh speed have been observed on coarse grids. With the present method, a change of limiter causes the solution to change from the physically correct CJ detonation solution to the spurious weak detonation solution. 相似文献
132.
Laboratory formation of four isomers of C5H2 molecule is reported and detection of the ring-chain isomer (isomer 1) of C5H2 in cosmic objects has been suggested. For identification of a molecule in cosmic objects, one of the required input data
is EinsteinA-coefficients (radiative transition probabilities) for the molecule. Here, we report EinsteinA-coefficients for electric dipole transitions in the ring-chain isomer of C5H2 among the rotational levels of the ground electronic and ground vibrational states up to 21 cm−1. 相似文献
133.
134.
The principal reactants interact in a molar ratio of 2:1 forming dihydroindophenol and the corresponding disulfide. The order of reaction is unity with respect to each reactant, namely, N-acetyl L-cysteine and indophenol. The rate shows an inverse linear relation with hydroxyl ions. It is not influenced by the variation in the initial concentration of indophenol. The rate increases on adding the salts possessing a cholinergic effect and the neutral electrolytes, as well as on increasing the dielectric constant of the medium. The products, namely, N-acetyl L-cystine (disulfide) and the leuco dye, do not influence the rate. A low energy and a highly negative entropy of activation (4.11 kcal/mol and -60.49 e.u., respectively) suggest the formation of an outer sphere complex as the rate-determining step. 相似文献
135.
The origin of the high- and low-frequency K-satellites of 31Ga, 32Ge, 33 As is explain on the basis of Hayasi's theory of quasi-stationary states. It is shown that the same QSS difference gives rise to a particular satellite of either type in all the elements. The results are compared with those of multiple ionisation theory. 相似文献
136.
Forbidden hyperfine transitions are observed in the electron spin resonance spectrum of divalent Mn55 ion in NaCl single crystal for a particular associated pair. From the measurements of the M = + 1/2 → ?1/2, Δm = ± 1 transitions the parametersQ′ and Q″ of the nuclear electric quadrupole part of the spin-Hamiltonian Ho = Q′ [Iz 2 ? 1/3 I (I + 1)] + Q″ (Ix 2?Iy 2) are found to be + 1.70 × 10?4 cm.?1 and +0.16 × 10?4 cm.?1 respectively. 相似文献
137.
Novel carbonium ion rearrangements of substituted 1,3-bishomocubanones & to tricyclo(4.2.0.03,8)octane and bicyclo(3.2.1)octane ring systems are reported. 相似文献
138.
The crystal field hamiltonian Hc = B20Y20 + B22(Y22 + Y2?2) commonly used in the study of electron-spin resonance is employed to obtain new contributions to the 57Fe3+ isomer shift in the Mössbauer effect. A numerical estimate of the shift is also presented. 相似文献
139.
The contribution of the ferroelectric soft-mode to the zero-field splitting is calculated and separated from the thermal contribution arising from the splitting due to the electron-phonon interaction. The predicted effect is compared with the measured values in Mn2+-doped NaNO2. 相似文献
140.
Hu X Jiao X Narayanan S Jiang Z K Sinha S Lurio LB Lal J 《The European physical journal. E, Soft matter》2005,17(3):353-359
We have used measurements of the absolute intensity of diffuse X-ray scattering to extract the interfacial tension of a buried polymer/polymer interface. Diffuse scattering was excited by an X-ray standing wave whose phase was adjusted to have a high intensity at the polymer/polymer interface and simultaneously a node at the polymer/air interface. This method permits the capillary-wave-induced roughness of the interface, and hence the interfacial tension, to be measured independently of the polymer/polymer interdiffusion. 相似文献