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21.
The Sublimation and the Thermal Decomposition of TeJ4 and the Existence of TeJ2 in the Gaseous Phase The sublimation and the decomposition of TeJ4 have been investigated. For the sublimation and the decomposition reactions and the values of enthalpy and entropy were derived (see ?Inhaltsübersicht”?). The existence of TeJ2 in the gaseous phase was demonstrated by equilibrium measurements and chemical transport experiments. 相似文献
22.
23.
A diagrammatic method is applied to study the effects of commensurability in two-dimensional disordered crystalline metals by using the particle-hole symmetry with respect to the nesting vector P0 = +/-pi / a,pi / a for a half-filled electronic band. The density of electronic states (DoS) is shown to have nontrivial quantum corrections due to both nesting and elastic impurity scattering processes, and as a result the Van Hove singularity is preserved in the center of the band. However, the energy dependence of the DoS is significantly changed. A small offset from the middle of the band gives rise to the disappearance of quantum corrections to the DoS. 相似文献
24.
The contributions of the dynamic fluctuations and the frozen-in inhomogeneities to the total light scattering intensity observed in poly(N-isopropylacrylamide)/clay nanocomposite hydrogels were analyzed by applying the nonergodic method proposed by Pusey and van Megen. Approximately 90% of the total scattering intensity corresponds to the frozen-in component. The scattering intensity of the fluctuating component is smaller by far than that of a pure clay suspension, indicating that the thermal fluctuations of the clay particles are largely suppressed upon network formation. Accordingly, the fluctuating component consists of two contributions: one due to the polymer chains and the other, smaller one representing the residual mobility of the clay particles. The latter depends on how tightly the clay particles are fixed in the network. The dynamic features of the nanocomposite hydrogels are described by two relaxation modes. The fast one is purely diffusive and can be related to a dynamic correlation length of 6-8 nm, which is similar to that of a corresponding polymer solution. The relaxation time of the slow mode varies appreciably with sample position even though the data had been treated with the nonergodic method. 相似文献
25.
O. Knöfler und H. Oppermann 《Fresenius' Journal of Analytical Chemistry》1890,29(1):177-178
Ohne Zusammenfassung 相似文献
26.
Reinhold Oppermann 《Zeitschrift für Physik A Hadrons and Nuclei》1973,258(4):285-300
The angular distributions of the α0 and α1 groups for the (n,α) reactions on11B,14N,16O have been measured atE n=14.1 MeV. In the11B(n, α0)8Li reaction the compound mechanism seems to be favoured as can be demonstrated with Hauser-Feshbach calculations. In the other reactions direct mechanisms dominate. 相似文献
27.
G-actin prepared from pork liver and purified to give a product of 95–98% purity was polymerized to F-actin in a rotational dynamic viscometer. The rheological properties were investigated during the course of polymerisation and after polymerisation.
G andG measured at frequencies around 0.1 Hz increased strongly during the first 3 hours of the reaction and then slowly approached a constant value in the range of 10–50 mPa. The rise during polymerisation was more than two orders of magnitude. When a solution of F-actin was subjected to steady shear at a high shear rate for a short period of time and subsequently dynamic measurements were performed, then a considerably smallerG (about 70% smaller) was observed immediately after cessation of the steady shear.G then increased with time and approached its initial value.When measuring the viscosity of F-actin solutions as a function of shear rate, a strong shear thinning effect was seen which did not vanish even at shear rates as low as 0.001 s–1. Even at this low shear rates, a pronounced yield maximum was observed before reaching the steady state. Oscillatory experiments showed a remarkably weak frequency dependence ofG.
The results imply that F-actin solutions are largely structured forming a weak temporary network which can be easily destroyed by application of high shear rates. It seems most likely that the destruction occurs by a reversible, shear induced depolymerisation process. 相似文献
28.
A. Koch H. Voges P. Andresen H. Schlüter D. Wolff W. Hentschel W. Oppermann E. Rothe 《Applied physics. B, Lasers and optics》1993,56(3):177-184
Rayleigh scattering of tunable excimer laser light (193 nm and 248 nm) is used to obtain 2-D images of the distribution of total densities in a laboratory flame and in a cylinder of an automobile engine. Because the UV light is very strongly scattered, there is ample signal and there is excellent contrast of Rayleigh light against surface scattered light, even in the small volume of the engine cylinder. The laboratory flame data are converted to an image of the temperature field. The Rayleigh images are compared with those from planar laser induced predissociative fluorescence, which yield state-specific densities of selected molecules. The experimental arrangement is the same except for the selection of laser wavelength and the filtering of the radiated light. 相似文献
29.
Chemical Transport in the System Mn? O in Consideration of the Oxygen Coexistence Pressure (I) The chemical transport of the coexistent phases Mn2O3? Mn3O4 and Mn3O4? MnO with Cl2, Br2, I2, HCl, HBr, and HI was analysed thermodynamically and experimentally. The mentioned transport agents are able to transport the following phases: 1 Index (o) bedeutet obere, (u) untere Phasengrenze (index (o) – upper phase boundary, (u) – lower phase boundary). . 相似文献
30.