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"This book covers novel research results for process and techniques of materials characterization for a wide range of materials. The authors provide a comprehensive overview of the aspects of structural and chemical characterization of these materials. Includes a compilation of the best research works presented in Symposium 5B "Structural and Chemical Characterization of Metals, Alloys and Compounds," by XXIII International Materials Research Congress (IMRC-2014)."

"ABSTRAKA natural-based nanocomposite film consisting of chitosan, montmorillonite (MMT) and cashew nut shell liquid (CNSL) was synthesized. The nanocomposite was prepared by mixing a suspension of clay particles (filler, MMT) with a solution containing chitosan as the macroscopic polymer matrix. In this study, it was proposed that non-ionic long-chain alkylmolecules with possible interact ions with the amine group of chitosan could be used as a plasticizer. As a natu-ral source for these compounds, an extract of CNSL was used. A series of chitosan/MMT com-posite samples containing two different clay contents and a sample with an additional CNSL were prepared. FTIR spectroscopy of the nanocomposite films indicated that, by addition of CNSL, amide groups of the chitosan are probably less attached and have more space for vibration. CNSL seems to provide intermolecular spaces between the chitosan molecules. Atomic force microscopy (AFM) analysis showed that the composite containedparticles measuring 100 nm or less, which confirmed that the nanocomposite had been successfully produced by this method. Addition of CNSL as plasticizer improved the tensile strength by 10% and the elastic modulus by almost 18%. Cell growth was observed on all the nanocomposite samples studied."

"The preparation and characterization of macro alginate beads are always associated with appropriate techniques involving precise measurement of shape, size, volume and density of the products. Depending on the type of application, encapsulation of macro alginate beads can be accomplished by various techniques including chemical, ionotropic, physical and mechanical methods. This work describes a method for preparing macro alginate beads through drop weight. The macro beads (2.85–3.85 mm) were prepared via different concentrations of alginate (0.5, 1.0, 1.5 and 2.0 g/L), dripping tip size (0.04–0.14 cm) and immersion into a predetermined concentration of calcium chloride (CaCl2) bath. A custom made dripping vessel fabricated from acrylic plastic, connected to an adjustable dripping clamp was used to simulate the dripping process of the molten alginate at different tip sizes. It was observed that at different dripping tips, the correction factor for the alginate slurry was found in the range of 0.73–0.83. Meanwhile, the lost factor, KLF was observed at 0.93–2.3 and the shrinkage factors were limited to 2.00% from the overall distributed data. It was concluded that liquid properties had no effect on the liquid lost factor. The bead size prediction for different concentrations of alginate solution was compared to the experimental data. Subsequently, it was concluded that increasing the tip size caused the bead size to deviate almost 20% when compared to the experimental and predicted values, respectively."

"Pembuatan TiO2 nanotube telah berhasil dilakukan. TiO2 nanotube dihasilkan dari proses anodisasi plat Ti dalam larutan elektrolit garam flourida dalam etilen glikol. Proses anodisasi dilakukan dengan menggunakan potensial 40 V selama 1 jam. TiO2 nanotube yang terbentuk kemudian didispersikan dalam larutan hidrogen peroksida, sehingga membentuk koloid TiO2. Penggunaan koloid TiO2 salah satunya adalah untuk melapisi TiO2 pada permukaan bahan agar memiliki kemampuan self cleaning. Pelapisan TiO2 pada kain dan kaca telah berhasil dilakukan. Pelapisan TiO2 pada kain diperlukan penambahan spacer kimia dan perendaman kain dalam koloid TiO2. Pada pelapisan permukaan kaca dengan TiO2 dilakukan dengan cara penetesan koloid TiO2 pada permukaan kaca. Permukaan bahan yang telah dilapisi TiO2 dikarakterisasi dengan menggunakan SEM, UV-Vis DRS, FTIR, dan Contact Angle Meter. Setelah terlapisi dengan TiO2 permukaan kain kaca diuji kemampuan self cleaning dengan menggunakan zat warna Rhodamin B. Telah didapatkan hasil pengujian aktivitas fotokatalis dari kain dan kaca yang telah terlapisi TiO2 dengan menggunakan iluminasi sinar matahari dan sinar UV. Kain yang telah terlapis TiO2 dapat mendegradasi zat warna sebesar 60,67% dengan iluminasi sinar UV selama 100 menit dan sebesar 75,63 % dengan iluminasi sinar matahari selama 180 menit. Kaca yang telah terlapis TiO2 dapat mendegradasi zat warna sebesar 53,01% dengan iluminasi sinar UV selama 60 menit, tidak terdeteksi pada 80 dan 100 menit dan sebesar 39,65% dengan iluminasi sinar matahari selama 20 menit, tidak terdeteksi pada 40, 60, 80 dan 100 menit.

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Preparation of TiO2 nanotubes have been successfully carried out. The TiO2 nanotubes were produced by anodizing Ti plate in proper electrolyte solution. Anodizing process is performed by using a potential of 40 V for 1 hour. The formed TiO2 nanotubes were then dispersed in the water containing hydrogen peroxide, to obtain TiO2 colloidal. The water base colloidal of TiO2 then was applied to prepare a cloth/fabric and glass those have a self cleaning property. TiO2 coating on the fabric required the addition of a chemical spacer and soaking fabrics in TiO2 suspension.

While surface coating of the glass with TiO2 done by dripping of glass surface in the colloidal of TiO2. The materials those have been coated with TiO2 the were characterized by using SEM, UV-Vis DRS, FTIR, and Contact Angle Meter. In addition the TiO2 coated glass fabric was tested its self-cleaning ability by using Rhodamine B dyes, under illumination of sunlight and UV rays.

The test result of cloth/fabric which has been coated TiO2 showed that under UV light illumination for 100 minutes, it can degrade the dye by 60,67%, while under with sunlight illumination for 180 minutes can degrade up 75,63%. For the glass that has been coated with TiO2, the test showed that, under illumination of UV light for 60 minutes, it can degrade 53,01% of the dye, not detected for 80 and 100 minutes and under illumination of the sunlight for 20 minutes can degrade 39,65% of the dyes, not detected for 40,60,80 and 100 minutes."

"CuO/TS-1 catalysts have been prepared and tested in the benzene hydroxylation. TS-1 was synthesized by hydrothermal method, while CuO/TS-1 was prepared by impregnation method using Cu(NO)2. 3H2O as precursor. Catalysts were characterized by using X-ray diffraction (XRD), infrared spectroscopy (IR), and N2 adsorption-desorption techniques. The catalytic activity was tested in the hydroxylation reaction of benzene. The products were analyzed using gas chromatography. Catalyst characterization by XRD and IR techniques have showed that the catalyst structure was a MFI type of zeolite. XRD pattern have showed the orthorombic structure and indicated the presence of CuO aggregation. The results of the pyridine adsorption have found that the acidity of TS-1 and CuO/TS-1 were a Lewis acid and it?s increased with an increasing amount of CuO loading. The results of nitrogen adsorption analysis have showed decreasing of surface areas of catalyst with increasing amount of CuO loading. The optimum conditions of benzene hydroxylation was observed by 1%CuO/TS-1 catalyst at 70 °C, reaction time 2 h and acetic acid as the solvent yielded 27.6% of phenol with phenol selectivity was 75.5%"

"The main problem with the slurry process is the difficulty in recovering the photocatalyst nanoparticle from water following purification. An alternative solution proposed the photocatalyst be immobilized on magnetic carriers, which would allow them to be recollected from the water suspension following treatment using an external magnetic field. Magnetically photocatalyst composites were prepared using simple heteroagglomeration by applying attractive electrostatic forces between the nanoparticles with an opposite surface charge. The Fe3O4/SiO2/TiO2 photocatalysts were synthesized in an aqueous slurry solution containing Fe3O4/SiO2 and TiO2 nanoparticles under pH 5 conditions. Meanwhile, Fe3O4/SiO2 was prepared by a simple procedure via a coprecipitation of iron(II) and iron(III) ion mixtures in ammonium hydroxide and was leached by sodium silicate. The synthesized samples were investigated to determine the phase structure, the magnetic properties, and the morphology of the composites by X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and transmission electron microscopy (TEM), respectively. The results indicated that the composites contained anatase and rutile phases and exhibited a superparamagnetic behavior. Fe3O4/SiO2 particles, which were of the aggregation spherical form at 20 nm in size, were successfully attached onto the TiO2 surface. The catalytic activity of Fe3O4/SiO2/TiO2 composites was evaluated for the degradation of methylene blue under ultraviolet (UV) irradiation. The presence of SiO2 as a barrier between Fe3O4 and TiO2 is not only improves the photocatalytic properties but also provides the ability to adsorb the properties on the composite. The Fe3O4/SiO2/TiO2 (50% containing TiO2 in composite) were able to eliminate 87.3% of methylene blue in water through the adsorption and photocatalytic processes. This result is slightly below pure TiO2, which is able to degrade 96% of methylene blue. The resulting Fe3O4/SiO2/TiO2 composite exhibited an excellent ability to remove dye from water and it is easily recollected using a magnetic bar from the water. Therefore, they have high potency as an efficient and simple implementation for the dye effluent decolorization of textile waste in slurry reactor processes."

"The main problem with the slurry process is the difficulty in recovering the photocatalyst nanoparticle from water following purification. An alternative solution proposed the photocatalyst be immobilized on magnetic carriers, which would allow them to be recollected from the water suspension following treatment using an external magnetic field. Magnetically photocatalyst composites were prepared using simple heteroagglomeration by applying attractive electrostatic forces between the nanoparticles with an opposite surface charge. The Fe3O4/SiO2/TiO2 photocatalysts were synthesized in an aqueous slurry solution containing Fe3O4/SiO2 and TiO2 nanoparticles under pH 5 conditions. Meanwhile, Fe3O4/SiO2 was prepared by a simple procedure via a coprecipitation of iron(II) and iron(III) ion mixtures in ammonium hydroxide and was leached by sodium silicate. The synthesized samples were investigated to determine the phase structure, the magnetic properties, and the morphology of the composites by X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and transmission electron microscopy (TEM), respectively. The results indicated that the composites contained anatase and rutile phases and exhibited a superparamagnetic behavior. Fe3O4/SiO2 particles, which were of the aggregation spherical form at 20 nm in size, were successfully attached onto the TiO2 surface. The catalytic activity of Fe3O4/SiO2/TiO2 composites was evaluated for the degradation of methylene blue under ultraviolet (UV) irradiation. The presence of SiO2 as a barrier between Fe3O4 and TiO2 is not only improves the photocatalytic properties but also provides the ability to adsorb the properties on the composite. The Fe3O4/SiO2/TiO2 (50% containing TiO2 in composite) were able to eliminate 87.3% of methylene blue in water through the adsorption and photocatalytic processes. This result is slightly below pure TiO2, which is able to degrade 96% of methylene blue. The resulting Fe3O4/SiO2/TiO2 composite exhibited an excellent ability to remove dye from water and it is easily recollected using a magnetic bar from the water. Therefore, they have high potency as an efficient and simple implementation for the dye effluent decolorization of textile waste in slurry reactor processes."