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This work aimed to study the recovery of two types of waste by the process of pyrolysis. The obtained results show that the adding of a plastic mix improves the overall efficiency of the slow pyrolysis of pine. Therefore, it was possible to achieve higher liquid yields and less solid product than in the classic slow pyrolysis carbonization of biomass. The obtained liquids showed heating values similar to that of heating fuel oil. The gas products had energetic contents superior to that of producer gas, and the obtained solid fractions showed heating values higher than some coals. There were also identified some typical products of fast biomass pyrolysis used as raw material in several industries. The effects of experimental conditions in product yield and composition were also studied. The parameters that showed higher influence were (with its increase): reaction time on gas product composition (increase of the alkane content) and on liquid composition (increase in aromatics content); reaction temperature on product yield (decrease of liquid yield with increase of solids and gases) and on gas product composition (increase in alkane content); initial pressure on liquid composition (increase in the aromatics content) and mainly the pine content of the initial mixture on products yield (increase of gas and solid yield with a decrease in liquids) and on the gas product composition (favouring CO and CO2 formation).

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Here we report the performance of a selective floating gate (V GS) n-type non-volatile memory paper field-effect transistor. The paper dielectric exhibits a spontaneous polarization of about 1 mCm-2 and GIZO and IZO amorphous oxides are used respectively as the channel and the gate layers. The drain and source regions are based in continuous conductive thin films that promote the integration of fibres coated with the active semiconductor. The floating memory transistor writes, reads and erases the stored information with retention times above 14500 h, and is selective (for VGS > 5 ± 0.1 V). That is, to erase stored information a symmetric pulse to the one used to write must be utilized, allowing to store in the same space different information. © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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Molybdenum doped (0-1 at. %) indium oxide thin films with high near infrared (NIR) transparency and carrier mobility were deposited on Corning-1737 glass substrates at 400 °C by spray pyrolysis experimental technique. Films with mobility as high as ∼149 cm2 /V s were obtained when annealed in vacuum at 550 °C, which also possess carrier concentration of ∼1× 1020 cm-3 and resistivity as low as ∼4.0× 10-4 cm. Further, both the average visible transmittance (500-800 nm) and the average NIR transmittance are >83%. This clearly shows that the transmittance is extended well into the NIR region. © 2009 American Institute of Physics.

In this work, we present the structural and electrical properties of HfO 2, HfO 2 +SiO 2, and HfO 2 +Al 2O 3 dielectric composite layers deposited by sputtering without any intentional substrate heating. The films were deposited on glass and 〈100〉 crystalline silicon (c-Si) substrates from ceramic targets by using argon (Ar) and oxygen (O 2) as sputtering and reactive gases, respectively. The incorporation of SiO 2 and Al 2O 3 into hafnia was obtained by co-sputtering and itwas controlled by adjusting the ratio of r.f. power applied between the targets. The HfO 2 films present a microcrystalline structure, when deposited at room temperature (RT). The lowest leakage current in c-Si MIS (Metal-Insulator- Semiconductor) structures (below 10 9A/cm 2 at 10V on films with a thickness around 180 nm) was obtained for an Ar/O 2 ratio of 14:1 sccm, and further increase in O 2 flow does not enhance the electrical characteristics. The codeposition of SiO 2 or Al 2O 3 with hafnia has a strong influence on the structure of the resulting films since they become amorphous. The leakage current in MISstructures incorporating these multi-component dielectrics is reduced at least by a factor of 2, which is accompanied by an increase on the band gap. The dielectric constant is decreased due to the lower values for SiO 2 and Al 2O 3. © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mathematics Subject Classification: 26A33, 76M35, 82B31A stochastic solution is constructed for a fractional generalization of the KPP (Kolmogorov, Petrovskii, Piskunov) equation. The solution uses a fractional generalization of the branching exponential process and propagation processes which are spectral integrals of Levy processes.

Zinc oxide is getting an enormous attention due to its potential applications in a variety of fields such as optoelectronics, spintronics and sensors. The renewed interest in this wide band gap oxide semiconductor relies on its direct high energy gap (Eg ∼ 3.437 eV at low temperatures) and large exciton binding energy. However to reach the stage of device production the difficulty to produce in a reproducible way p-type doping must be overcome. In this study we discuss the structural and optical properties of ZnO films doped with nitrogen, a potential p-type dopant. The films were deposited by magnetron sputtering using different conditions and substrates. The composition and structural properties of the films were studied combining X-ray diffraction (XRD), Rutherford backscattering (RBS), and heavy ion elastic recoil detection analysis (HI-ERDA). The results show an improvement of the quality of the films deposited on sapphire with increasing radio-frequency (RF) power with a preferentially growth along the c-axis. The ERDA analysis reveals the presence of H in the films and a homogeneous composition over the entire thickness. The photoluminescence of annealed samples evidences an improvement on the optical quality as identified by the well structured near band edge recombination. © 2009 Elsevier Ltd. All rights reserved.

The coordination properties of the beta-keto phosphine ligands R(2)PCH(2)C(O)Ph (HL(1), R = i-Pr; HL(2), R = Ph), of the new acetamide-derived phosphine ligand (i-Pr)(2)PNHC(O) Me (HL(3)) and of Ph(2)PNHC(O) Me (HL(4)) have been examined towards Ni(II) complexes. Comparisons are made between systems in which the PCH(2) function of the ketophosphine has been replaced with an isoelectronic PNH group in amide-derived ligands, or the PCH functionality of phosphinoenolates with a PN group in phosphinoiminolate complexes. Furthermore, ligands HL(2) and HL(4) reacted with [(eta(5)-C(5)H(5))CoI(2)(CO)] to afford the phosphine mono-adducts [(eta(5)-C(5)H(5))CoI(2){Ph(2)PCH(2)C(O)Ph}] (1) and [(eta(5)-C(5)H(5))CoI(2){Ph(2)PNHC(O)Me}] (3), respectively, which upon reaction with excess NEt(3) yielded the phosphinoenolate complex [(eta(5)-C(5)H(5))CoI{Ph(2)PCH (center dot center dot center dot) under barC((center dot center dot center dot) under barO)Ph}] (2) and the phosphinoiminolate complex [(eta(5)-C(5)H(5))CoI{Ph(2)PN (center dot center dot center dot) under barC((center dot center dot center dot) under barO)Me}] (4), respectively. The complexes cis-[Ni{(i-Pr)(2)PN (center dot center dot center dot) under barC((center dot center dot center dot) under barO)Me}(2)] (6) and cis-[Ni{Ph(2)PN (center dot center dot center dot) under barC((center dot center dot center dot) under barO)Me}(2)] (7) were obtained similarly from NiCl(2) and HL(3) and HL(4), respectively, in the presence of a base. The phosphinoenolate complex [Ni{(i-Pr)(2)PCH (center dot center dot center dot) under barC((center dot center dot center dot) under barO) Ph}(2)] (5) exists in ethanol as a mixture of the cis and trans isomers, in contrast to cis-[Ni{(Ph(2)PCH (center dot center dot center dot) under barC((center dot center dot center dot) under barO)Ph}(2)], and the solid-state structure of the trans isomer of 5 was established by X-ray diffraction. The structures of the ligand HL3 and of the complexes 1, 3 in 3 center dot 3/2CH(2)Cl(2), 4, 6 and 7 have also been determined by X-ray diffraction and are compared with those of related complexes. Complexes 4, 6 and 7 contain a five-membered heteroatomic metallocyclic moiety, which is constituted by five different chemical elements. The structural consequences of the steric bulk of the P substituents and of the electronic characteristics of the P, O chelates are discussed.

{A stochastic representation for the solutions of the Poisson-Vlasov equation is obtained. The representation involves both an exponential and a branching process. The stochastic representation, besides providing an alternative existence proof and an intuitive characterization of the solutions, may also be used to obtain an intrinsic definition of the fluctuations. (c) 2007 Elsevier B.V. All rights reserved.}

{We consider a positive distribution Phi such that Phi defines a probability measure mu = mu Phi on the dual of some real nuclear Frechet space. A large deviation principle is proved for the family \{mu(n), n >= 1\} where mu(n) denotes the image measure of the product measure mu(n)(Phi) under the empirical distribution function L(n). Here the rate function I is defined on the space F(theta)'(N')(+) and agrees with the relative entropy function (H) over tilde (Psi/Phi). As an application, we cite the Gibbs conditioning principle which describes the limiting behaviour as n tends to infinity of the law of k tagged particles Y(1),...,Y(k) under the constraint that L(n)(Y) belongs to some subset A(0).}

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A series of cobalt(II) compounds of the type [CoX2(alpha-diimine)] were synthesised by direct reaction of anhydrous CoCl2 or CoI2 and the corresponding alpha-diimine ligand, in CH2Cl2: [CoI2(o,o',p-Me3C6H2-DAB)] ( 1), [ CoI2(o,o'-(Pr2C6H3)-Pr-i-DAB)] ( 2), ( where Ar-DAB = 1,4-bis(aryl)-2,3-dimethyl-1,4-diaza-1,3-butadiene), and [CoCl2(o,o',p-Me3C6H2- BIAN)] (3), [CoCl2(o,o'- (Pr2C6H3)-Pr-i-BIAN)] (4), and [CoI2(o,o'-(Pr2C6H3)-Pr-i-BIAN)] (5) (where Ar-BIAN = bis(aryl) acenaphthenequinonediimine). All compounds were characterised by elemental analyses, IR, mass spectrometry, and X-ray diffraction whenever possible. The crystal structures of compounds 2-4 showed, in all cases, distorted tetrahedral geometries about the Co, built by two halogen atoms and two nitrogen atoms of the alpha-diimine ligand. Compounds 3 and 4, as well as [ CoCl2(o,o',p-Me3C6H2-DAB)] (1a), and [ CoCl2( o,o'- (Pr2C6H3)-Pr-i- DAB)] (2a), were activated by methylaluminoxane (MAO) and tested as catalysts for ethylene polymerisation, showing low catalytic activities. Selected polyethylene ( PE) samples were characterised by H-1 and C-13 NMR and FT-IR spectroscopies, and by differential scanning calorimetry (DSC), revealing branching microstructures (2.5-5.5%). (c) 2007 Elsevier B. V. All rights reserved.

The development of more efficient power converters is the most important and challenging task for Power Electronics specialists. In the same time, many currently existing or yet to appear future applications require full mechanical independence between the transmitter and receiver of the electrical energy. This contactless form of energy transfer is the concern of the presented work. The work is based on the study of the Series Loaded Series Resonant converter which prove to be the best suitable for the contactless energy transfer. The work investigates the idealized Series Resonant Power Converter with the objective to find the best efficiency zones of operation. Generalized expressions obtained are original and useful. Based on the magnetic parameters of the loosely coupled transformer (magnetic link), the characteristics of the contactless power converter are described in approximated form. The approximation permits easier and faster calculation of the converter variables, thus predicting a shift of the maximum efficiency zone compared to the ideal converter case. The approximated form of the equations permitted to present a new instantaneous form of regulation which combines the frequency and pulse width modes which is free from the previously known defects. The method is based on calculating the energy portions supplied to the load during each half period. Measurements performed on industrial converters and on the laboratory experimental converter, confirm the predicted theoretically behaviour of the converter.

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