Tao Zhang,Soo‐Young Park,B. L. Farmer,Leonard V. Interrante,Synthesis of comb‐type polycarbosilanes via nucleophilic substitution reactions on the main‐chain silicon atoms,Journal of Polymer Science Part A: Polymer Chemistry (2003) 41(7) 984–997

The original article to which this erratum refers was published in Journal of Polymer Science Part A: Polymer Chemistry (2003) 41(7) 984–997 No abstract.     

Deformations of Maass forms

We describe numerical calculations which examine the Phillips-Sarnak conjecture concerning the disappearance of cusp forms on a noncompact finite volume Riemann surface under deformation of the surface. Our calculations indicate that if the Teichmüller space of is not trivial, then each cusp form has a set of deformations under which either the cusp form remains a cusp form or else it dissolves into a resonance whose constant term is uniformly a factor of smaller than a typical Fourier coefficient of the form. We give explicit examples of those deformations in several cases.

     

Differentiation evens out zero spacings

If is a polynomial with all of its roots on the real line, then the roots of the derivative are more evenly spaced than the roots of . The same holds for a real entire function of order 1 with all its zeros on a line. In particular, we show that if is entire of order 1 and has sufficient regularity in its zero spacing, then under repeated differentiation the function approaches, after normalization, the cosine function. We also study polynomials with all their zeros on a circle, and we find a close analogy between the two situations. This sheds light on the spacing between zeros of the Riemann zeta-function and its connection to random matrix polynomials.

     

Hermitian geometries in projective space

Using a Hermitian form on a vector space over GF (l), we produce a geometry on the associated projective space and prove that this geometry is characterized by its plane sections.     

Surface chemistry and electrical properties of germanium nanowires

Germanium nanowires (GeNWs) with p- and n-dopants were synthesized by chemical vapor deposition (CVD) and were used to construct complementary field-effect transistors (FETs). Electrical transport and X-ray photoelectron spectroscopy (XPS) data are correlated to glean the effects of Ge surface chemistry to the electrical characteristics of GeNWs. Large hysteresis due to water molecules strongly bound to GeO(2) on GeNWs is revealed. Different oxidation behavior and hysteresis characteristics and opposite band bending due to Fermi level pinning by interface states between Ge and surface oxides are observed for p- and n-type GeNWs. Vacuum annealing above 400 degrees C is used to remove surface oxides and eliminate hysteresis in GeNW FETs. High-kappa dielectric HfO(2) films grown on clean GeNW surfaces by atomic layer deposition (ALD) using an alkylamide precursor is effective in serving as the first layer of surface passivation. Lastly, the depletion length along the radial direction of nanowires is evaluated. The result suggests that surface effects could be dominant over the "bulk" properties of small diameter wires.     

A cyanide‐bridged bimetallic complex, [CrPr(CN)6(C3H7NO)4(H2O)3]·H2O

The crystal structure of the bimetallic cyanide‐bridged title complex, tri­aqua‐1κ³O‐μ‐cyano‐1:2κ²N:C‐penta­cyano‐2κ⁵C‐tetrakis(N,N‐di­methyl­form­amide)‐1κ⁴O‐chromium(III)­prase­odymium(III) monohydrate, was obtained by single‐crystal X‐ray diffraction. The central praseodymium(III) ion is eight‐coordinate, arranged in a square antiprism, while the chromium(III) ion is six‐coordinate, oriented octahedrally. Molecules in the crystal lattice are held together by a network of hydrogen bonds.     

The Determination of Arsenic in Soil and Sediment Digests by Graphite Furnace Atomic Absorption Spectrometry

Abstract

A method for the determination of As in siliceous materials from a fluoboric acid matrix by GFAAS is described. The basic analytical procedure also permits the measurement of major, minor and other trace elements by flame or graphite furnace AAS as appropriate. For As analysis, the incorporation of matrix modification with Ni and of corrective measures to overcome interference by Al, Na and Si are discussed. The validity of the method is demonstrated by the accurate analysis of four international standard reference materials and agreement with instrumental neutron activation analysis results for As in environmental samples. One application to the study of As geochemistry in lacustrine sediments is presented.