A direct method for the decontamination of a fly ash amended wet soil,artificially polluted with dioxins

We report hereby the first method of direct treatment of a wet soil containing toxic polychloroderivatives. Using a system with metallic Ca and 5% Rh fixed on charcoal in methanol, soil samples artificially polluted with fly ash containing polychloro-dibenzodioxins (PCDDs), polychloro-dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (co-PCBs), and having 69.2% to 84.6% moisture content, were successfully treated and decontaminated. This treatment afforded excellent hydrodechlorination yields for the 29 most toxic congeners of PCDDs, PCDFs and PCBs (98.3% degradation yield based on toxic equivalent quotient — or TEQ) after a 24 h treatment, at room temperature.      

Chip-nanoelectrospray quadrupole time-of-flight tandem mass spectrometry of meningioma gangliosides: a preliminary study

A strategy combining high-performance thin layer chromatography (HPTLC), laser densitometry, and fully automated chip-based nanoelectrospray (nanoESIchip) performed on a NanoMate robot coupled to QTOF-MS was developed, optimized, and for the first time applied for mapping and structural identification of gangliosides (GGs) extracted and purified from a human angioblastic meningioma specimen. While HPTLC pattern indicated only seven fractions migrating as GM3, GM2, GM1, GD3, GD1a (nLD1, LD1), GD1b, GT1b, and possibly GD2, due to the high sensitivity, mass accuracy, and ability to ionize minor species in complex mixtures, nanoESIchip-QTOF MS was able to discover significantly more GG species than ever reported in meningioma. Thirty-four distinct glycosphingolipid components of which five asialo, one GM4, nine GM3, two GM2, two GD3, nine GM1, and six GD1 differing in their ceramide compositions were identified. All structures presented long-chain bases with 18 carbon atoms, while the length of the fatty acid was found to vary from C11 to C25. MS screening results indicated also that the diversity of the expressed GM1 structures is higher than expected in view of the low proportions evidenced by densitometric quantification. Simultaneous fragmentation of meningioma-associated GM1 (d18:1/24:1) and GM1 (d18:1/24:0) by MS/MS using CID confirmed the postulated structures of the ceramide moieties and provided data on the glycan core, which document that for each of the GM1 (d18:1/24:1) and GM1 (d18:1/24:0) forms both GM1a and GM1b isomers are expressed in the investigated meningioma tissue.     

Interfacial ternary complex DNA/Ca/lipids at anionic vesicle surfaces

The electroporative transfer of gene DNA and other bioactive substances into tissue cells by electric pulses gains increasing importance in the new disciplines of electrochemotherapy and electrogenetherapy. The efficiency of the electrotransfer depends crucially on the adsorption of the gene DNA and oligonucleotides to the plasma cell membranes. Here it is shown that the adsorption of larger oligonucleotides such as fragments (ca. 300 bp) of sonicated calf-thymus DNA, to anionic lipids of unilamellar vesicles (diameter Phi=300+/-90 nm) is greatly enhanced by divalent cations such as Ca(2+)-ions. Applying centrifugation, bound and free DNA are monitored optically at the wavelength lambda=260 nm. Using arsenazo III as a Ca(2+)-indicator and atomic absorption spectroscopy (AAS), Ca(2+)-titrations of DNA and vesicles yield the individual equilibrium constants of Ca(2+)- and DNA-binding not only for the binary complexes: Ca/lipids, Ca/DNA and DNA/lipids, respectively, but also for the various processes to form the ternary complex DNA/Ca/lipids. The data provide the basis for goal-directed optimization protocols for the adsorption and thus efficient electrotransfer of oligonucleotides and polynucleotides into cells.     

Sheaves on abelian surfaces and strange duality

We formulate three versions of a strange duality conjecture for sections of the Theta bundles on the moduli spaces of sheaves on abelian surfaces. As supporting evidence, we check the equality of dimensions on dual moduli spaces, answering a question raised by Göttsche et al. (K-theoretic Donaldson invariants via instanton counting. arXiv:math/0611945).     

Recursive prediction error identification of fractional order models

This paper deals with time domain identification of fractional order systems. A new identification technique is developed providing recursive parameters estimation of fractional order models. The identification model is defined by a generalized ARX structure obtained by discretization of a continuous fractional order differential equation. The parameters are then estimated using the recursive least squares and the recursive instrumental variable algorithms extended to fractional order cases. Finally, the quality of the proposed technique is illustrated and compared through the identification of simulated fractional order systems.     

Catching an Entatic State—A Pair of Copper Complexes

The structures of two types of guanidine–quinoline copper complexes have been investigated by single‐crystal X‐ray crystallography, K‐edge X‐ray absorption spectroscopy (XAS), resonance Raman and UV/Vis spectroscopy, cyclic voltammetry, and density functional theory (DFT). Independent of the oxidation state, the two structures, which are virtually identical for solids and complexes in solution, resemble each other strongly and are connected by a reversible electron transfer at 0.33 V. By resonant excitation of the two entatic copper complexes, the transition state of the electron transfer is accessible through vibrational modes, which are coupled to metal–ligand charge transfer (MLCT) and ligand–metal charge transfer (LMCT) states.     

Relations between synthesis and microstructural properties of copper/zinc hydroxycarbonates

Cu/Zn Hydroxycarbonates obtained by co-precipitation of Cu(2+) and Zn(2+) with Na(2)CO(3) have been investigated regarding phase formation and thermal decomposition in two series with varying Cu/Zn ratios prepared according to the decreasing pH and constant pH method. Hydrozincite, aurichalcite and (zincian)-malachite were found to form at differing Cu/Zn ratios for both series. For the constant pH preparation the Cu/Zn ratio in zincian-malachite was close to the nominal values whereas excess values were found for the decreasing pH samples. The degree of crystallinity as well as the thermal decomposition temperatures were lower for the constant pH series. All samples containing aurichalcite revealed an unexpected decomposition step at high temperatures evolving exclusively CO(2). The differences in composition and microstucture were traced back to the different pathways of solid formation for the two preparation methods. Substantial changes were observed during the post-precipitation processes of ageing and washing. The effects were studied in detail on samples with a cation ratio of Cu/Zn 70:30 mol %. Ageing of the precipitates in their own solutions is accompanied by a spontaneous crystallization of the initially amorphous solids. The decreasing pH sample develops from a hydroxy-rich material comprising basic copper nitrate (gerhardtite) as an intermediate. Only small changes in the chemistry of the samples were detected for the constant pH precipitation. The findings are summarised into a scheme of solid formation processes that explains the phenomenon of a "chemical memory" of the precipitates when they are converted into Cu/ZnO model catalysts.     

High temperature oxidative resistance of polyacrylonitrile-methylmethacrylate copolymer powder converting to a carbonized monolith

The doping of polyacrylonitrile (PAN) prior to carbonization can alter the physicochemical nature of the polymer under thermal treatment. The inclusion of a “lower” thermally stable monomer methyl methacrylate (MMA) enables fusion of PAN particles into monoliths and, depending on the heating rate, can control the expansion of the structure and establish pore formation through the volatilization and escape of its thermal degradation products. Moreover, geometry is maintained through the carbonization step, when heated up to 850 °C. The exothermic regime of PAN-co-MMA is much broader and the cyclization reaction starts at a lower temperature compared with that of the PAN homopolymer. TGA reveals that the thermal stability of the copolymer, compared with pure PAN at 800 °C, has increased by 30 wt.% in air, which is far higher than reported in previous studies of copolymers of PAN. The results show promise in providing a facile mechanism for the production of monolithic PAN-based carbons with the potential of controlled porosity.