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131.
The use of different plasma models for composition calculations of nonideal plasmas can result in very different electron concentrations for the same experimental situation characterized e.g. by the measured temperature and pressure. This gives rise to misunderstandings at comparison of theoretical and experimental results. For extreme conditions i.e. in the region of the supposed plasma phase transition results of solid state physics give us the possibility to rule out some plasma models.  相似文献   
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Combining biologic pretreatment with storage is an innovative approach for improving feedstock characteristics and cost, but the magnitude of responses of such systems to upsets is unknown. Unsterile wheat straw stems were upgraded for 12 wk with Pleurotus ostreatus at constant temperature to estimate the variation in final compositions with variations in initial moisture and inoculum. Degradation rates and conversions increased with both moisture and inoculum. A regression analysis indicated that system performance was quite stable with respect to inoculum and moisture content after 6 wk of treatment. Scale-up by 150× indicated that system stability and final straw composition are sensitive to inoculum source, history, and inoculation method. Comparative testing of straw-thermoplastic composites produced from upgraded stems is under way.  相似文献   
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Let p be a prime number and a natural number. If E is a r-connected finite CW-complex of dimension at most pr, then E is an example of a p -Anick space. For p > 2 we construct a commutative cochain algebra over that is an -model of the free loop space on a p-Anick space, i.e., its cohomology algebra is isomorphic to the mod p cohomology of the free loop space. For p-Anick spaces that are p-formal, such as spheres and projective spaces, we define an even simpler commutative free loop space model that applies for all primes p. We then use the simplified model to compute the cohomology algebras of a number of free loop spaces explicitly. Received: 23 June 1999; in final form: 8 September 2000 // Published online: 7 April 2003  相似文献   
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Ohne Zusammenfassung über Teiledervorliegenden Abhandlungist erstmalig am 1. 6. 1954 auf dem X. Internationalen Kongre? der Ern?hrungsindustrien in Madrid sowie am 6. 9. 1954 auf der B?ckereitagung in Detmold berichtet worden.  相似文献   
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Applying the new technique for finding the converged solution of the Boltzmann equation in a weakly ionized plasma, which was developed in the first part of this paper, a comprehensive study of the electron velocity distribution function for a model plasma with elastic and exciting collisions is performed by solving the Boltzmann equation with increasing order of approximation. The purpose of this investigation is that of calculating the isotropic distribution f0, the first contribution f1 to the anisotropy of the velocity distribution, the important macroscopic quantities and, more generally, that of studying the total anisotropy as well as the changes of all these quantities when the approximation degree is enlarged beyond the 2 terms of the conventional Lorentz approximation. By varying some parameters of the model plasma, that is the electric field strength, the magnitude of the excitation cross section and the excitation threshold, the main features of plasmas in inert as well as molecular gases are modelled and the impact of these parameters on the mentioned quantities is analysed. Some of the converged results are compared with results of corresponding Monte Carlo simulations. The approximation degree required to find the converged values of isotropic distribution, main macroscopic quantities and electron distribution in the velocity space (and thus its real anisotropy) is estimated by solving the Boltzmann equation over wide parameter ranges.  相似文献   
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Methyldicarboxylatostibanes and -bismuthanes These compounds are received either by reacting of Methyldibromostibanes and -bismuthanes with Sodium-carboxylates or by reacting Diethoximethylstibane and -bismuthane with the free acids.  相似文献   
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