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Mathematics achievement and interest in mathematics from a differential perspective

In this article, we present results of an empirical study with 500 German students of grades 7 and 8. The study focussed on students' mathematics achievement and their interest in mathematics as well as on the relation between these two constructs. In particular, the results show that the development of an individual student's achievement between grade 7 and grade 8 depends on the achievement level of the specific classroom and therefore on the specific mathematics instruction Interest in mathematics could be regarded a predictor for mathematics achievement Moreover, our findings suggest that the students show hardly any fear of mathematics independent of their achievement level.     

On the correspondence between rotational bands in the mass regionsA ≃ 100 andA ≃ 150

A refined technique is presented to project rotational bands observed in the well studiedZ≧60 rare-earth region into the region of stable ground-state deformation atA ～-100 with corresponding neutron numbers ofN ≧60. With this procedure, estimates of properties of so far unknown nuclei in the A～-100 region can be obtained. As an illustration, isotopes aroundN=64 are discussed within this projection method and within the frame-work of the recent quartet model.     

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Diophantine equations between polynomials obeying second order recurrences

Periodica Mathematica Hungarica -     

Fast switching ferroelectric side-chain liquid-crystalline polymer and copolymer

New ferroelectric side-chain liquid-crystalline polymers, a copolymer and a homopolymer, with siloxane backbone and a triaromatic mesogen as the side group have been synthesized. The materials exhibit a chiral smectic C phase over a large temperature range extending to room temperature. They possess high values of spontaneous polarization: 105 nC cm^-2 for the homopolymer and 180 nC cm^-2 for the copolymer. The electro-optic switching time in the chiral smectic C phase is extremely fast (150 μs). In the smectic A phase, an electroclinic effect with switching times less than 100 μs and with field induced tilt angles of 18° is observed.     

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