Jusami | Indonesian Journal of Materials Science
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Adsorption of Phenol and Iron In Wastewater Using a Mixture of Active Carbon and Zeolite Modified with Chitosan
Full text linkPhenol (C6H5OH) and iron (Fe2+) contained in electroplating industrial wastewater are toxic even at small concentrations. One of the effective methods to remove these compounds is adsorption because the method is easy and simple. Activated carbon and zeolite are types of adsorbents that are often used in wastewater treatment, but both types of adsorbents are not selective in certain chemicals. In this study, modification of zeolite and activated carbon with chitosan was carried out to adsorb waste containing phenol and Fe2+. The variations used were pH (7 and 9) and the adsorbent composition to study its effect on the adsorption of phenol in the presence of Fe2+. Adsorption was carried out in a bed with circulating waste for 2 hours. Feed at pH 9 with adsorbent mixed of zeolite-chitosan composite (Z-Ch) and activated carbon-chitosan composite (AC-Ch) in a ratio of 1:1 gave the optimal results. Under these conditions, 94% and 97% of phenol and Fe2+ were adsorbed, respectively
Influence of Applied Potential on The Structural and Optical Properties of Cu2O Thin Films Grown by Electrochemical Deposition
Full text linkCu2O thin films have been deposited on indium-tin-oxide (ITO) coated glass substrate by electrochemical method or electrodeposition. The effect of deposition potential on the microstructure and optical properties of Cu2O thin films was studied. Electrodeposition for two Cu2O thin films was carried out at –0.5V and –0.6V relative to the standard calomel electrode (SCE) as a reference electrode. Cu2O thin films were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and UV-Visible spectroscopy. The diffraction pattern indicated the cubic structure of the Cu2O crystal has been well grown. The lattice parameters of Cu2O films slightly increased as the potential of electrodeposition increased. The crystallite size of Cu2O films significantly increased as the applied potential increased. Cu2O thin films showed a smooth and flat surface morphology based on SEM images. The optical transmittance of the Cu2O thin films drastically decreased as the applied potential increased due to the film thickness increasing. The bandgap energy of Cu2O films based on the Tauc plot increased as the applied potential increased, that is 2.0 eV for the film deposited at -0.5V and 2.13 eV deposited at -0.6V
MECHANICAL PROPERTIES OF PINEAPPLE LEAF FIBER/ EPOXY COMPOSITES WITH 0°/0°/0°/0° AND 0°/90°/0°/90° FIBER ORIENTATIONS
Full text linkMECHANICAL PROPERTIES OF PINEAPPLE LEAF FIBER/ EPOXY COMPOSITES WITH 0°/0°/0°/0° AND 0°/90°/0°/90° FIBER ORIENTATIONS. Pineapple leaf fiber can replace synthetic fiber because of its environmentally friendly and abundant availability in Indonesia. The purpose of this study was to obtain the mechanical properties of the pineapple leaf fiber/epoxy composite with 0°/0°/0°/0° and 0°/90°/0°/90° fiber orientations. Pineapple leaf fiber from Subang Indonesia was pre-treated through alkalization. The composites were fabricated by hand lay-up, followed by the vacuum bagging method. The results showed that the flexural properties of both composites were higher than the tensile properties of both composites. The flexural strength and modulus of 0°/0°/0°/0° composites were higher than those of 0°/90°/0°/90° composites, with the values of (109.57 ± 8.12) MPa and (7.08 ± 0.62) GPa respectively. Morphological observations using a Scanning Electron Microscope (SEM) showed that pineapple leaf fiber and epoxy had strong interfacial bonds and few voids. According to SNI 01-4449-2006 for fiberboard, pineapple leaf fiber/ epoxy composites with 0°/0°/0°/0° and 0°/90°/0°/90° fiber orientations were categorized as high-density fiberboard type T2 45, because both composites had a density higher than 0.84 g/cm3 and a flexural strength higher than 45 MPa
Influence of Glucose, Urea and Bacteria Concentration On Nata De Cassava Preparation Using Liquid Tapioca Waste Medium
No full textIn this research, Nata de Cassava as the obtained bacterial cellulose was synthesized by Acetobacter xylinum using the liquid tapioca waste as the media. This research aimed to investigate the influence of concentration from carbon and nitrogen sources and then the type of bacteria used toward the obtained Nata de Cassava. The liquid tapioca waste was heated in a beaker glass at 70-80 °C and then added 5-10 % (w/v) of sugar and 0.1-0.5 % (w/v) of urea. The mixed solution was poured into a container and then cooled. Furthermore, 10-20 % (v/v) of Acetobacter xylinum was added and incubated at room temperature. After ten days, the Nata de cassava was harvested, sterilized, and immersed in ethanol, then dried in an oven at 60 °C. The results of FTIR, XRD and SEM analysis showed that Nata de Cassava had been successfully synthesized. The composition that produced the highest Nata de Cassava yield of 2.41% was the composition using 15% of A. xylinum, 10% of glucose and 0.1% of urea in the fermentation medium. In addition, the composition that produced the highest carbon conversion ratio of 26.15% was the composition that used 10% of A. xylinum, 5% of glucose and 0.2% of urea in the fermentation medium
The Effect of Conventional and Sonochemical Synthesis Methods on Gd2O3 Nanoparticles Properties
Full text linkParamagnetic Gd2O3 nanoparticles have been widely used as a contrast agent in bioimaging such as Magnetic Resonance Imaging (MRI). In this study, Gd2O3 nanoparticles were prepared using conventional and sonochemically precipitation methods, without any stabilizers. Gadolinium nitrate was used as a precursor and ammonium hydroxide as precipitating agent. The synthesized Gd2O3 nanoparticles were characterized using X-Ray Diffractometer (XRD), Particle Size Analyzer (PSA), Scanning Electron Microscope (SEM), and Vibrating Sample Magnetometer (VSM). It was found that Gd2O3 nanoparticles obtained in both methods have a cubic phase. The saturation magnetization (Ms) values of conventional and sonochemical samples were 1.63 emu/g and 1.44 emu/g respectively. The morphology of both samples shows agglomerated spherical shape in the nanometer range. The nanoparticles size of Gd2O3 that was confirmed by the Dynamic Light Scattering technique show samples from the sonochemical method has narrower size distribution (higher homogeneity) compare to samples from the conventional method. It was also found that the sonochemical synthesis technique is faster (time-saving), simple, convenient, and environmentally benign
THE ADVANCED ELECTRIC FIELD FROM QUAD-ELECTRODE MODE FOR BLOOD CANCER TRAPPING: SIMULATION STUDY
No full textTHE ADVANCED ELECTRIC FIELD FROM QUAD-ELECTRODE MODE FOR BLOOD CANCER TRAPPING: SIMULATION STUDY. Blood cancer is a disease caused by the rapid cleavage of white blood cells (WBC), which increases in the human circulatory system. Furthermore, based on the original nature of WBC during cleavage, which is the same as ionic bonds, electric field filtering, and trapping is used to treat leukemia patients. The electric field generated by the electrode with an AC voltage source plays a role in the migration of the WBC to high electric field intensity. The Quad-electrode field distribution is conducted using the Finite Element Method (FEM), and an electric field gradient analysis is conducted to determine the effectiveness of each coordinate system. According to the simulation results, the second model with an input voltage of 0.68 V has the highest intensity of electric field distribution, with an effective depth at Z = 30 mm, and the best coordinate along the X-axis and Y-axis are 30 mm. In conclusion, the center of the Quad-electrode system center is the best location for placing filters and trapping leukocytes by utilizing electric field distribution on the electrode system for the development of blood cancer biomedical therapy technology
Ag AND Pd FISSION PRODUCT IMPLANTATION ON SiC LAYER IN TRISO FUEL PARTICLE OF HTGR USING SRIM/TRIM MONTE CARLO COMPUTER
Full text linkAg AND Pd FISSION PRODUCT IMPLANTATION ON SiC LAYER IN TRISO FUEL PARTICLE OF HTGR USING SRIM/TRIM MONTE CARLO COMPUTER. Silicon Carbide (SiC) has excellent characteristics such as wide band gap, high electron mobility, high thermal conductivity, and radiation effects resistance. Therefore, SiC is widely used for various applications, including nuclear fuel systems. SiC is used in TRISO (Tri-Structural Isotropic) coated fuel particle in HTGR (High Temperature Gas cooled Reactor). TRISO, which consists of Inner Pyrolitic Carbon, SiC, and Outer Pyrolitic Carbon, is one of the safety systems features of the reactor. However, one of the issues of the system is corrosion of SiC caused by silver (Ag) and palladium (Pd). Nevertheless, the detailed mechanism of this corrosion phenomenon, such as the existence of Ag and Pd and how deep those two fission products penetrate the SiC layer, are still unknown. This study aims to investigate the physical interaction of Ag and Pd with the SiC coating layer of TRISO nuclear fuel particles. For this purpose, the physical effect of the penetration of the energetic Pd and Ag fission products into the SiC layer has been simulated using SRIM (Stopping and Range of Ions in Matter) /TRIM (TRansport of Ions in Matter) computer code with Monte Carlo method. Various Ag and Pd ion kinetic energies have been employed in this simulation. The results showed the Ag/SiC and Pd/SiC Ion Ranges, Doses, and Damage as the first-step evaluation to understand the corrosion phenomenon of the SiC-layer in the TRISO particles of HTGR
