Abstract The present research proposed the use of construction and demolition waste (CDW) in adsorption of methylene blue dye in aqueous medium. CDW was studied in its natural form and calcined aiming to improve its properties, both being characterized by different techniques and subjected to adsorption studies. From the kinetic study, it was verified that both systems presented a better fit to the experimental data for the pseudo-second-order model (R2 >0.980). The concentration and temperature variation showed a maximum adsorption capacity of 112.23 mg.g-1 (natural) and 418.6 mg.g-1 (calcined) both for the temperature of 45 ºC. The experimental data fit better with the Langmuir isotherm model, with a correlation coefficient R2 ≥0.960 for both samples. It was observed that both residues presented favorable adsorption mechanisms and effective adsorption parameters, but the calcined sample presented better results, and thinking in a low-cost material, natural sample can be more economically advantageous. In this view, CDW represents a potential and promising alternative for water purification. (CDW medium properties studies study pseudosecondorder pseudo second order R (R >0.980. 0980 >0.980 . 0 980 >0.980) 11223 112 23 112.2 mg.g1 mgg1 mgg mg.g 1 mg g mg.g- (natural 4186 418 6 418. (calcined 4 ºC 0960 960 ≥0.96 samples parameters results lowcost low cost material advantageous view purification 098 >0.98 98 1122 11 2 112. g1 41 096 96 ≥0.9 09 >0.9 9 ≥0. >0. ≥0 >0 ≥ >

This work reports on the properties of GaN films grown by reactive magnetron sputtering onto glass substrate kept at relatively low temperature (400°C), using different RF power applied to the Ga target. Their structural, morphological, vibrational and optical properties were characterized by X-ray diffraction, atomic force and scanning electron microscopies, Raman spectroscopy and UV-vis spectrophotometry. The films have wurtzite phase with strong preferential orientation in the c-axis direction. Moreover, two clear contributions to the (0002) diffraction peak could be found, indicating the presence of two different morphologies, which were discussed in terms of the formation of an intermediate layer between the substrate and a dominating columnar-like microstructured film. 400°C, 400C C 400°C , 400 (400°C) target structural morphological Xray X ray microscopies UVvis UV vis spectrophotometry caxis c axis direction Moreover 0002 (0002 found morphologies columnarlike columnar like film 40 (400°C 000 (000 4 00 (00 0 (0 (

Abstract This work reports the properties of GaN films grown onto c-Si (100) at relatively low substrate temperature (400°C) by reactive magnetron sputtering. The study depicts the effect of working pressure and RF power on the GaN film structural, vibrational and optical properties characterized by X-ray diffraction, atomic force and scanning electron microscopies, Raman spectroscopy and spectroscopic ellipsometry. Unusual low pressure deposition condition (0.40 Pa) was achieved by using a separated argon inlet directed to the Ga target surface, resulting in improved crystalline quality of the films. In this condition, the preferential crystalline orientation, the surface morphology and the optical gap of the GaN films show a strong dependence on the RF power applied to the Ga target, where low RF power (30-60 W) was responsible for increasing the c-axis orientation and the optical gap, while higher RF power (75-90 W) decreased the overall crystal quality and increased the surface roughness.