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This study aims to enhance the H2/N2 separation performance of polysulfone (PSF) hollow fiber membranes by annealing. X-ray diffraction, SEM, and FESEM were utilized to evaluate morphological and structural changes in denser annealed PSF membranes. AFM topography images were used to investigate the annealed form and roughness of PSF membranes. Before testing membrane permeation, it was annealed at 120, 150, and 190 °C to optimize gas separation performance. Compare to all annealing temperatures (120, 150, and 190 °C), the annealed PSF membrane at 150 °C had the greatest H2/N2 selectivity (16.18), but its separation performance was unsatisfactory since it was below the Robeson upper limit curve. The PSF before annealing and the PSF annealed at 190 °C showed outstanding separation performance (2.60 and 2.71, respectively), despite their lower selectivity than the PSF annealed at 150 °C. [ABSTRACT FROM AUTHOR]

This study aims to investigate the effects of different solvents (isopropanol, benzene, and toluene) on the synthesis of carbon-modified TiO2/H-ZSM-5 composites. Carbon-modified TiO2/H-ZSM-5 composites were characterized by FTIR, XRD, and SEM. XRD analysis revealed that the TiO2 peaks at 2 = 25.3, 37.8, and 48.2° had distinct characteristics. FTIR analysis revealed that I-ZTC, B-ZTC, and T-ZTC had comparable absorption bands to ZSM-5 at 3464, 1639, 1222, 1097, and 545 cm-1, respectively. Additionally, the FTIR data revealed that I-ZTC, B-ZTC, and T-ZTC all display absorption bands around the wavenumber 450 cm-1, indicating the Ti-O bond's stretching vibration. Additionally, SEM-EDX analysis revealed that Ti was more evenly distributed on the surface of T-ZTC than on the surfaces of B-ZTC and I-ZTC. It was shown that the solvent's polarity has an effect on TiO2 dispersion. A less polar solvent disperses TiO2 more effectively. In terms of TiO2 dispersion, toluene was the preferable solvent for the production of carbon-modified TiO2/H-ZSM-5. [ABSTRACT FROM AUTHOR]

To deal with a problem of overlapping data in pattern classification, a class majority method in designing hidden units of Fuzzy Local Approximation NN is proposed. Moreover, to improve the output confidence of the networks, Euclidean fuzzy similarity is proposed as hidden unit operator. For each cluster formed by the adaptive clustering of F-SONIA, the number of vectors that belong to the same class is calculated. Therefore the fractions of each class are known. One class should have a single class majority in the cluster. Then, the cluster with no single majority is broken down into two clusters. In experiments, the real-world benchmark datasets, e.g., 2-D vowel, Iris, and thyroid data that have different challenges to the networks in terms of overlapping and size are used to test the networks. Experiments show that the proposed methods improve the classification performance as well as the output confidence of the networks. [ABSTRACT FROM AUTHOR]