Weak toroidalization over non-closed fields

We prove that any dominant morphism of algebraic varieties over a field k of characteristic zero can be transformed into a toroidal (hence monomial) morphism by projective birational modifications of source and target. This was previously proved by the first and third author when k is algebraically closed. Moreover we show that certain additional requirements can be satisfied.     

1. Ueber die Einwirkung von Stickoxydgas auf Eisen-oxydull?sungen

Ohne Zusammenfassung     

Characterization of Transfer Functions of Pritchard–Salamon or Other Realizations with a Bounded Input or Output Operator

We show that the transfer functions that have a (continuoustime) well-posed realization with a bounded input operator are exactly those that are strong-H² (plus constant feedthrough) over some right half-plane. The dual condition holds iff the transfer function has a realization with a bounded output operator. Both conditions hold iff the transfer function has a Pritchard–Salamon (PS) realization. A state-space variant of the PS result was proved already in [3], under the additional assumption that the weighting pattern (or impulse response) is a function (whose values are bounded operators). We illustrate by an example that this does not cover all PS systems, not even if the input and output spaces are separable.     

Phase behaviors and interactions of N-alkylated polyanilines and ethylene-co-vinyl acetate blends

Conjugated polyanilines bearing long alkyl side chains (dodecyl PANi-12 and octadecyl PANi-18) were prepared for the purpose of obtaining well-mixed conducting polymer blends with insulating flexible polymers. The miscibility of the polyanilines and ethylene-co-vinyl acetate copolymers (EV A20 with 20 wt % of vinyl acetate and EV A70 with 70 wt %) was significantly improved by long alkyl chains of the same hydrocarbon moieties as the ethylene segments in the matrix EV A, as demonstrated by microscopic observation. PANi-18/EV A20 blends exhibit a lower critical phase separation temperature (LCST). In addition, the EV A crystallinity and the side-chain crystallinity in the miscible blends were depressed, as shown by thermal analysis and x-ray scattering. The comparison of three designed blend systems indicates that the miscibility of the polymers is determined by the hydrophobic interaction between the hydrocarbon units in the both components and by the hydrogen bonding. The solvatochromic phenomena for the blends at low miscible PANi compositions was detected by UV-visible spectroscopy. The threshold conductivities exhibit sensitivity to the morphological structure of the polymeric blends, and was lowered by improved homogenous dispersion of the conducting phase. © 1995 John Wiley & Sons, Inc.     

Natural extensions for piecewise affine maps via Hofbauer towers

We use canonical Markov extensions (Hofbauer towers) to give an explicit construction of the natural extensions of various measure preserving endomorphisms, and present some applications to particular examples.     

Hard Lefschetz theorem for simple polytopes

McMullen’s proof of the Hard Lefschetz Theorem for simple polytopes is studied, and a new proof of this theorem that uses conewise polynomial functions on a simplicial fan is provided.     

Kloosterman sum identities and low-weight codewords in a cyclic code with two zeros

We apply relations of n-dimensional Kloosterman sums to exponential sums over finite fields to count the number of low-weight codewords in a cyclic code with two zeros. As a corollary we obtain a new proof for a result of Carlitz which relates one- and two-dimensional Kloosterman sums. In addition, we count some power sums of Kloosterman sums over certain subfields.     

Potentiometric monitoring DNA hybridization with polyaniline/Nylon-6 working electrode

Electrically conducting polymers are useful in various applications such as transistors and sensors. A potentiometric pH meter has been developed using polyaniline based working electrode and with improved selectivity using ionophores, the polyaniline based potentiometer has been applied to monitor various ions mainly in environmental applications. The polyaniline working electrode can be used to monitor not only the binding of a biological ionic macromolecules on polyaniline surface but also the binding of the adsorbed macromolecule with another macromolecule. We present first how the working electrode was prepared by polymerization of aniline in Nylon-6 matrix to provide the mechanical strength and then how single strand oligonucleotide probe binds with polyaniline surface. We then present how an electrode modification with mercaptoethanol results in a surface protected against non-specific binding and then finally we present the results of monitoring the complimentary strand binding leading to the formation of the double strand DNA. The text was submitted by the authors in English.