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Research was conducted to examine the synthesization of two novel, isostructural, one-dimensional tellurites of molybdenum(VI), (NH4)4Mo6TeO22*2H2O and Rb4Mo6TeO22*2H2O using the hydrothermal approach. Characterization was also examined by means of single-crystal X-ray diffraction methods. The structure, hydrothermal syntheses, spectroscopy, powder X-ray diffraction and thermal studies of the compounds were also carried out.

Research was conducted to examine Gd(DOTA)- and Gd(DTPA)2- complexes in the crystalline state and aqueous solutions for various pH values at room temperature and other temperatures using X-ray absorption fine structure analysis. Results demonstrate that the complexes are very rigid. The experimental Fourier transforms of the complexes studied as crystals and in aqueous solutions can be easily explained by mass spectrometric calculations.

An automated particle analysis routine is implemented on an electron microprobe for analyzing the chemical composition and projective area of populations of individual silver halide microcrystals. An LN2 cryostage is used to prevent material degradation due to reaction with the impinging electron beam. The background in the EDX spectra is lowered by depositing the microcrystals on a carbon-coated copper grid, mounted in a transmission holder. The IL[Alpha]/AgL[Alpha] net X-ray intensity ratio, obtained from a spectrum-fitting algorithm, is used to determine the crystal composition by means of a standard-based calibration curve. The uncertainty on the concentration measurement of individual microcrystals is calculated using the uncertainties on the net X-ray counts and the uncertainties on the calibration curve. The area measurement is optimized by introducing a gray value histogram correction on each individual measurement. Overlapping microcrystals are scrapped from the analysis by defining a maximum shape factor, against which the shape factor of the microcrystal is tested. To minimize problems with drift of the cryostage, spectrum acquisition is carried out immediately after a single microcrystal has been located, based on the backscattered electron image. Several applications are discussed.

Research was conducted to examine the low-temperature chlorination of GaAs(100). Soft X-ray photoelectron spectroscopy, which employs syhnchrotron radiation, was used to investigate the chemisorption and the reaction of chlorine and hydrogen chloride on the GaAs surface at 110 K. Results provide an insight into the reaction mechanism of the synchrotron radiation-induced etching of the GaAs surface by Cl2 at low temperatures.

A low-temperature solid-state synthetic method for the preparation of the tetragonal infinite layer phase of SrCuO2 based on pulsed laser deposition (PLD) is presented. The synthesis is performed in a stainless steel vacuum chamber evacuated with a turbomolecular pump. The desired SrCuO2 is synthesized from a 1:1 mixture of SrCO3 and CuO, giving the product in the orthorhombic phase. Ablation and deposition of the orthorhombic SrCuO2 gives the tetragonal layered phase.

Research was conducted to examine the crystal structure of the xylanase from Penicillium simplicissimum. The binding of the natural, unmodified substrates to the native enzyme and the mapping of the xylose subunit binding sites using the substrate as cryoprotectant with a series of xylooligosaccharides were performed. Results demonstrate that the two catalytic residues divide the binding cleft into a substrate recognition area with strong and specific xylan binding and a product release area with considerably weaker and less specific binding.