nan Andoko

Properties of Y3Fe5O12 (YIG) as Nanocatalyst for Ammonia Formation Produced from Magnetic Induction Method (MIM)

Production of ammonia required high capital energy intensive such as high temperatures (400 to 500 °C) and high pressure (15 to 30 MPa). We investigated a new way to produce green ammonia synthesis using new nanocatalyst and operate in room temperature and ambient pressure. The idea is to synthesize ammonia using Magnetic Induction Method (MIM) and Y3Fe5O12 (YIG) as magnetic nanocatalyst. YIG was prepared by sol gel method and sintered at various temperatures 950 °C, 1050 °C, and 1150 °C. X-Ray Diffraction (XRD) result shows that the major peak at [420] plane. The balance composition of YIG resulted by Energy Dispersive X-Ray (EDX) is in the form of Y3Fe5O12. Initial permeability results show, the highest value maximum permeability at 140 with the range of frequency 1Hz to100MHz obtained by 950 °C sample. The lowest value of relative loss factor obtained by 950 °C sample. YIG nanocatalyst and MIM method were successfully produce ammonia yield at 197 μmol, without MIM the yield was decreased by 14.28%.

Comparison study on mechanical properties single step and three step artificial aging on duralium

Duralium is kind of non-ferro alloy that used widely in industrial. That caused its properties such as mild, high ductility, and resistance from corrosion. This study aimed to know mechanical properties of duralium on single step and three step articial aging process. Mechanical properties that discussed in this study focused on toughness value, tensile strength, and microstructure of duralium. Toughness value of single step artificial aging was 0.082 joule/mm2, and toughness value of three step artificial aging was 0,0721 joule/mm2. Duralium tensile strength of single step artificial aging was 32.36 kgf/mm^2, and duralium tensile strength of three step artificial aging was 32,70 kgf/mm^2. Based on microstructure photo of duralium of single step artificial aging showed that precipitate (θ) was not spreading evenly indicated by black spot which increasing the toughness of material. While microstructure photo of duralium that treated by three step artificial aging showed that it had more precipitate (θ) spr...

Characteristics of leaf spring strength of material 65si7 and material C17000 using finite element method

leaf spring is a vital component in a motor vehicle - particularly in car either with light tonnage or with heavy tonnage. It is needed to function both as the load buffer and as a shock absorber. This simulation was aimed to observe the strength of leaf spring due to the loading by varying the tilt angles or curvature on two different materials: composite material of 65Si7 and composite material of C17000. The declivity of leaf spring here consists of 0, 5, 10, 15 and 20°C.The result of the analysis showed that the characteristic of leaf spring using the material of composite of 65Si7 has resulted in the maximum stress compared to the leaf spring using the material of composite C17000. The characteristic of leaf spring using the material of composite C17000 has resulted in the total deformation and the strain larger than that of the leaf spring using the composite material of 65Si7. For the use of leaf spring on vehicle, it is better to use the composite material 65Si7 rather than the composite material ...

Finite element analysis of surface tension on piston due to pressure variation

Piston is an important component of the motor vehicle that can pump or result in a pressure thus enabling to generate the components to reciprocate the engine. Commonly, it is made of mixed aluminum in which in the work process of engine, it receives the high level of pressure and heat that later emerges the pressure on the surface. To observe the distribution of the surface pressure on the piston due to the high pressure and temperature, it cannot be manually done but by means of the approach of the finite element method through the Ansys sofware. The variation of the simulated surface pressures consisted of 5, 10, 15 and 20 MPa with various pedestals given. Based upon the simulation result, it was found that the variety of the pressures received by the piston surface has caused the level of pressure experienced by piston also changed. It was similar with the result of the use of different positions of pedestals in which it could lead to a change in the pressure concentration of piston.

Tensile strength differences and type of fracture in artificial aging process of duralium against cooling media variation

Duralium has mild character, high ductility, and resistance from corrosion. Doing heat treatment against this alloy by cooling variation can increase strength and ductility of this alloy. Cooling media variations which is used for this research are 10% dromus oil + water, 20% dromus oil + water, and 30% dromus oil + water. The purpose of this research is knowing the tensile strength of duralium in artificial aging process against cooling media variation 10% dromus oil + water, 20% dromus oil + water, and 30% dromus oil + water, type of fracture, and phase changing of duralium. This research include in experimental research category which uses the one-shot case study research model. Tensile testing uses Hung Ta Instrument machine and type of fracture is observed from micro and macro photo of duralium. The aging result shows that tensile strength of duralium increase from 8.3304 Kg/mm2 to 8.6229 Kg/mm2. This is due from aging result which is formed precipitates evenly due to the difference of cooling media ...

Synthesis and Characterization of Zinc Oxide Nanoparticles via Self-Combustion Technique

Zinc oxide (ZnO) is a unique material which has been used in many researches. However synthesizing nanosize ZnO remains a challenge. This deal with the preparation of ZnO nanoparticles was synthesized by a self-combustion technique. In the self-combustion technique, nanoparticles was obtained by heating the materials until the mixture combusts at 110°C. ZnO nanoparticles were synthesized from Zn (NO3)2.6H2O precursor observed in two different solvent. The first set of experiment involved dissolving Zn (NO3)2.6H2O in nitric acid (HNO3) and adding ZnO, whereas for the second Ethylene Glycol (C2H6O2) was used as the solvent. The material was stirred at 250 r.p.m continuously for 1 month and 3 days. The mixture was then heated up until it combusted at 110°C. Samples were then annealed at 400°C for 1 hour . The ZnO samples were characterized using X-Ray Diffraction (XRD), Raman Spectroscopy, and Field Emission Scanning Electron Microscope (FESEM). The XRD analysis showed major peak at 20-30 of 2 theta scale with [10, [00, and [10 plane of the wurtzite hexagonal structure for both sets of ZnO samples. Samples were observed at raman shift for 138 and 439 cm-1 and 141 and 443 cm-1 before and after annealing. Synthesized ZnO 1 resulted the morphology of single crystal nanorods with average dimensions of 18 nm wide and 154 nm long. ZnO 2 has obtained the morphology of single crystal nanosphere with average diameter of 30 nm.Keywords: Zinc Oxide, Ethylene Glycol, Self-Combustion Technique