Some special features of the dissolution of cellulose in the dimethylacetamide-lithium chloride system

Conclusions The effect of the character of the activating treatment on change in cellulose crystalline structure, its degree of polymerization, swelling, and thermodynamic parameters of the spinning solutions has been investigated.A probable mechanism for the activation has been suggested, which consists of an unblocking of the capillary walls of the cellulosic material, and not of the capillaries themselves, which is confirmed by data from the experimental studies.Translated from Khimicheskie Volokna, No. 2, pp. 10–11, March–April, 1989.     

Der Aufbruch zum „funktionalen Denken“: Geschichte des Mathematikunterrichts im Kaiserreich

  By the end of the 19th century, mathematics teaching underwent a crisis of similar proportion in several European countries. Constrained by the values of classical Antiquity, which dominated in secondary education, mathematics was taught as a formal discipline enhancing elementary geometry and intended as some gymnastics of the mind. Moreover, a specific feature in Germany was that the country was split up into numerous independent states each having a separated educational system of its own. Many of these conferred an only marginal status to mathematics instruction. This complex situation is analyzed for the traditional school system for boys, as well as for the emerging system for girls, and for primary schooling. The study describes the key initiatives by Felix Klein, who forged a dynamic movement of teachers for modernising secondary school teaching. Their culmination in the famous “Meran” reform program is depicted, a program which became the starting point for the first international reform movement in mathematics teaching.

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Renate Tobies zum 60. Geburtstag gewidmet.     

Climate change negotiations and first-mover advantages: the case of the wind turbine industry

Individual EU member countries, such as Denmark and Germany, may have a rational economic interest in creating comparative advantages for renewable energy sources in order to capitalise on their first-mover advantages in these industries. We demonstrate that different means of implementing the Kyoto Agreement affect the potential to market new renewable technologies, e.g. wind turbines, to other countries subsequent to their ratification of the Kyoto target levels. This article shows that a transnationally grandfathered Tradable Permit System (TPS) renders the shadow price of emissions reductions lower in the high-cost reduction countries. Export opportunities to these countries will consequently be reduced under a transnational TPS, e.g. from the EU to the US. This could also serve to explain EU opposition to a fully flexible TPS in The Hague in 2001. Instead, the latest EU proposal delivered in Johannesburg pushed for setting a target of 15% of all energy to come from sources of renewable energy, e.g. wind turbines, solar panels, biomass and waves, by 2015. Such initiative would further EU industrial interests globally. Future research should, however, attempt to provide more empirical evidence concerning this proposition and its importance compared to other concerns.     

On renewal inner channels and block code error control superchannels

We investigate the statistical distributions of three events, namely the block error detection, correction and misdetection events of a block code on a discrete renewal inner channel, when this inner channel can be modeled by means of a partitioned Markov chain. In order to represent the above mentioned statistical distributions, we introduce the concept of a “super channel model.” Analytical procedures to determine some of the parameters of these super channel models are presented. The application of these models in the design of error control systems, such as ARQ systems, is investigated     

Vorgänge bei der Bildung primärer Desoxydationsprodukte in Stählen

Desoxydation unlegierter Stahlschmelzen mit Titan; Versuchsdurchführung. Auswertung der Ergebnisse für die verschiedenen Eisenschmelzen mit Vergleichen zur Aluminiumdesoxydation. Deutung der Versuchsergebnisse. Einschlußuntersuchung mittels Rückstandsuntersuchung. Desoxydation nichtrostender Chrom-Nickel-Stähle mit Aluminium. Folgerungen.