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111.
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113.
K. Fischer D. Linzen E. Sinn H. Stieff F. Voigt 《Crystal Research and Technology》1979,14(12):1521-1524
More Precise knowledge of the growth mechanism of garnets in form of epitaxial layers or single crystals in high temperature solutions on the base of trivalent oxides Me2O3 in PbO B2O3 solvent is desirable. Data of physicochemical properties of the melts especially density, shear viscosity, and electrical conductivity and their dependence on the temperature are useful in endeavour to recognize the structural principles of oxidie melts. Therefore as a first step the binary system PbO Ga2O3 was investigated to understand the influence of the Ga component on a complete mixed garnet solution, for instance (Y, Sm)3 (Fe, Ga)5O12 in PbO B2O3 solvent. 相似文献
114.
K. Fischer 《Crystal Research and Technology》1976,11(6):635-644
A DTA-apparatus is described which is suitable for solubility measurements of garnets in flux melts. It is important that the temperature will be measured as near as possible to the crystallization region. Solubility temperatures are measured with an uncertainty ≦ 10 deg. A mixture of PbO, PbF2 and B2O3 was used as solvent. The following garnet systems were investigated: Y3Fe5−xMxO12 (M = Ga, Al, In, Cr; x = 0 …︁ 5) and Gd3Ga5O12. If results of other authors are available they are in good agreement with our data. Habit and chemical analysis of crystallites give informations about the grown phases and their composition. In connexion with the solubility thus it is possible to select appropriate solvents. 相似文献
115.
Abstract Acylations at the 6-position of alkyl glycosides were obtained using the esterification potential of lipases. Thus, sugars with two alkyl chains result showing columnar discotic phases. The correlation between the configuration of the sugar moieties and the different clearing points can be understood on the basis of simple stereochemical assumptions. 相似文献
116.
Melt processing is a critical step in the manufacture of polymer articles and is even more critical when dealing with inhomogeneous polymer–clay nanocomposites systems. The chemical composition, and in particular the clay type and its organic modification, also plays a major contribution in determining the final properties and in particular the thermal and long-term oxidative stability of the resulting polymer nanocomposites. Proper selection and tuning of the process variable should, in principle, lead to improved characteristics of the fabricated product. With multiphase systems containing inorganic nanoclays, however, this is not straightforward and it is often the case that the process conditions are chosen initially to improve one or more desired properties at the expense of others. 相似文献
117.
O. Daillant D. Boilley M. Josset B. Hettwig H. W. Fischer 《Journal of Radioanalytical and Nuclear Chemistry》2013,297(3):437-441
In literature quite a lot of data is available on uptake of radioactive caesium in mushrooms. There is less available on the evolution of concentration in fruitbodies after several years and on “outbound” transfer of radiocaesium from fruitbodies to their direct environment, i.e. dilution according to cooking techniques. The recent event at Fukushima has put the question of radionuclides in food, and the following exposure of consumers, high on the agenda. The purpose of this paper is twofold: (1) in order to investigate the variation in time of caesium uptake by fungi, analyses of the same species having grown on the same spot at different intervals during the last 25 years have been performed and (2) in terms of radiation protection the most important thing is the activity taken in by the consumer and not the contamination of raw products. Preparation can have a great impact on activity concentration. Various species of mushrooms frequently eaten have been sampled in Europe and contaminated areas in Japan. Different preparation techniques that can break the walls of the hyphae (drying, deepfreezing etc.) have been applied as well as different treatments: boiling or macerating in water with salt, in acid and basic media. The pH of different media was adjusted and measured. The samples and the medium were analysed separately in gamma spectrometry. 相似文献
118.
We construct planar bi-Sobolev mappings whose local volume distortion is bounded from below by a given function with . More precisely, for any we construct -bi-Sobolev maps with identity boundary conditions; for , we provide bi-Lipschitz maps. The basic building block of our construction are bi-Lipschitz maps which stretch a given compact subset of the unit square by a given factor while preserving the boundary. The construction of these stretching maps relies on a slight strengthening of the celebrated covering result of Alberti, Csörnyei, and Preiss for measurable planar sets in the case of compact sets. We apply our result to a model functional in nonlinear elasticity, the integrand of which features fast blowup as the Jacobian determinant of the deformation becomes small. For such functionals, the derivation of the equilibrium equations for minimizers requires an additional regularization of test functions, which our maps provide. 相似文献
119.
120.
Bei Zhou Yousef Heider Andreas Blaeser Stefan Raith Horst Fischer Bernd Markert 《PAMM》2016,16(1):117-118
The aim of this work is to numerically simulate the gelation of a crosslinking polymer, which is a very complex process involving chemical reactions and phase transitions from a viscous fluid to a viscoelastic solid. A phenomenological model is proposed to simulate the gelation process of agarose droplets, considering the thermal boundary conditions. The numerical model is implemented using the finite element package FlexPDE. The temperature- and time-dependent degree of gelation and the deformation of the droplets during the gelation process are investigated. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献