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In this study, the synthesis of magnetite-CS/AC/titania nanocomposite was carried out to produce a new adsorbent agent for heavy metal (Cu) adsorption. The nanocomposite was characterized using X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and atomic adsorption spectroscopy (AAS). Based on the analysis of the XRD data, the nanocomposite exhibited magnetite phase detected at 2θ of 30.35°;35.64°; 43.25°; 53.66°; 57.31°; and 62.76°, while the AC phase was detected at 2-theta of 22.82°-24.65°. Furthermore, titania diffraction peaks were detected at 2θ of 25.28°; 37.93°; 48.06°; 54.24°; 55.07°; 62.85°; and 68.81°. The SEM image showed that the nanocomposite has an average particle size of 51.84 nm. Based on the FTIR-spectrum, the presence of Fe-O was detected at wavenumbers of 595 cm−1 and 453 cm−1, N-H and Ti-O-Ti were founded at wavenumbers of 1667 cm−1 and 653 cm−1, C = O and C = C were observed at wavenumbers of 1613 cm−1 and 1706 cm−1, meanwhile O-H and N-H were detected at wavenumbers of 3240 cm−1 and 3503 cm−1. The analysis result for the nanocomposite AAS data showed that the adsorption capacity for heavy metal (Cu) was 86.9%. [ABSTRACT FROM AUTHOR]

This study aimed to synthesize nanosized Mg0.2Fe2.8O4/AC/TiO2 composite for removal Pb(II) from water. The crystal structure and functional group of the sample were evaluated using XRD and FTIR spectroscopy. The morphology and band gap energy of the sample were characterized by means of SEM and UV-Vis spectroscopy. Meanwhile, the absorbance performance of the composite for removal Pb(II) was evaluated using AAS characterization. The results of the data analysis in this study showed that the Mg0.2Fe2.8O4/AC/TiO2 composite was successfully synthesized using coprecipitation method. The result of the XRD characterization presented the two phases for Mg0.2Fe2.8O4 and TiO2. The FTIR characterization results showed that the composite had a Fe-O bond at the tetrahedral and octahedral positions that were detected in the wavenumber range of 800–500 cm−1. The SEM image showed that the morphology of composite tended to agglomerate with a particle size distribution of 44.3 nm. The band gap energy resulting from the UV-Vis data analysis was 3.492 eV. Interestingly, the absorption efficiency for removal Pb(II) of the Mg0.2Fe2.8O4/AC/TiO2 composite reached 99.08%–99.90%. [ABSTRACT FROM AUTHOR]

In this study, Nd:YAG laser pulse is used to ablate the Magnesium sample for laser induced breakdown spectroscopy analysis. The emission lines are plotted for ionic and atomic element of Mg I and Mg II respectively. The emission lines of Mg I and Mg II were recorded at wavelength of 279.55 nm, 280.27 nm and 285.21 nm. The analysis including the different of gate delay, determination of signal to background ratio and calibration curve of different concentration of magnesium is discussed in details. [ABSTRACT FROM AUTHOR]

Carbon nanostructures become more useful nowadays due to their unique carbon elements and advantages. This paper will present the determination of the energy of carbon ion in different environments and pressures. In this work, arc discharge plasma generated by graphite electrode were chosen to produce carbon nanostructures and CR-39 material were exposed to energetic carbon ion. It was etched with 6.25 M of NaOH solution for 8 hours in (72 ± 1) °C temperature to remove the material from the tracks and the etched detectors will be analyzed with optical microscope. The energy of carbon ion obtained by observing and measured the ion track size on CR-39 target under optical microscope and calculated using the relevant formula. High values of carbon ions energy were observed in hydrogen environment as compared to air at the same pressure. [ABSTRACT FROM AUTHOR]

In this study, graphite laser induced plasma dynamics are investigated by optical emission spectroscopy. Graphite plasma is generated using a 1064 nm Nd:YAG laser in helium environment under different ambient pressures. Characteristics of graphite spectra as lines intensity variations and signal to noise ratio are presented with main focus on the influence of the helium environment and pressure on plasma dynamics. Carbon atomic emission lines are used to study the dynamical behavior of plasma such as the excitation temperature and electron density to describe emission differences in different ambient conditions. The excitation temperature and plasma electron density are the primary factor contribute to the differences among the atomic carbon emission in different ambient pressures. [ABSTRACT FROM AUTHOR]