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The aim of this paper is to extend and generalize Picard-Green's fixed point iteration method for the solution of fourth-order Boundary Value Problems. Several numerical applications to linear and nonlinear fourth-order Boundary Value Problems are discussed to illustrate the main results. [ABSTRACT FROM AUTHOR]

In a previous paper [8] the second author showed that there exists no conservative Hausdorff matrix with certain structural properties such as a band matrix with band width greater than one, or which has any column with only a finite number of nonzero entries. In this paper these restrictions are shown to also hold for the class of generalized Hausdorff matrices which we call H-J matrices. [ABSTRACT FROM AUTHOR]

We obtain the conditions for a large class of nonnegative triangular matrix transformations to map positive monotone decreasing sequences into positive monotone decreasing sequences. [ABSTRACT FROM AUTHOR]

Due to high operating temperature (800–1000 °C) of SOFC's, limited number of alloys can be employed for the purpose of current collection. The electrical conductivity of these alloys usually decreases during the operation of SOFC because of highly corrosive cathode (air side) environment. Cr evaporation from such alloys is also an important problem of performance degradation. A spinel Mn 1.5 Co 1.5 O 4 and perovskite La 0.60 Sr 0.40 FeO 3 mixture is coated on Crofer alloy for corrosion and chromium protection in the cathode side of a SOFC. In study firstly, the performance of the fuel cell with the Crofer 22 APU as interconnect material was measured up to 100 h without any coating. Secondly, using a screen printing method, bare Crofer 22 APU was coated with Mn 1.5 Co 1.5 O 4 and finally Mn 1.5 Co 1.5 O 4 + La 0.60 Sr 0.40 FeO 3 ceramic powder slurries were employed as the coating material. Then, the performances of a SOFC short stack with interconnects coated by two methods were compared with uncoated interconnect. Results show that uncoated interconnect experienced a significant performance lost from 4.5 W to 3.8 W. On the other hand the cells with screen printing coated with a mixture Mn 1.5 Co 1.5 O 4 and La 0.60 Sr 0.40 FeO 3 exhibited decreases only from 5.78 W to 5.42 W in the short-term performance tests. [ABSTRACT FROM AUTHOR]

In this paper, we present the synthesis of different metal-doped TiO 2 compounds (pure TiO 2 , Fe doped TiO 2 (Fe x Ti 1-x O 2), Ni doped TiO 2 (Ni x Ti 1-x O 2), Zr doped TiO 2 (Zr x Ti 1-x O 2)) thin films in order to improve the performance of dye-sensitized solar cell (DSSC). Undoped TiO 2 particles and Ni, Fe and Zr transition metals doped TiO 2 particles were synthesized by the sol-gel method for the utilization of the anodic part of the DSSC. The cathode of the DSSC was a carbon electrode. Fluorine Doped Tin Oxide (FTO) coated electrodes on the glass surfaces and electrolyte solution containing I/I 2 was obtained a dye-sensitized solar cell. Pure TiO 2 and Ni, Fe and Zr doped TiO 2 nanopowders were characterized by DLS, XRD, SEM/EDX, and UV–Vis Spectroscopy. The thin films have been deposited on the glass substrate by the doctor blade method. The effect of synthesized nano-materials on the cell performance of DSSC was investigated by J-V curves. J-V characterization of solar cell module shown that the highest power conversion efficiency was the solar cell module that fabricated with 10% of Zr doped TiO 2 with the short circuit current (Jsc) and the efficiency was at 0.13 mA cm−2 and 0.020%, respectively. However, yields on the cell performance of other nanomaterials were obtained as 0.019%, 0.017% and 0.015% for pure TiO 2 , Fe doped TiO 2, and Ni doped TiO 2 , respectively. • Different metal-doped TiO 2 compounds were synthesized by the sol-gel method. • Pore size distribution, energy differences of valance band and band gap affected photocatalytic activity. • J-V characterization of solar cell module showed Ni-doped TiO 2 gives best efficiency. [ABSTRACT FROM AUTHOR]