http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Mohd Azmuddin Abdullah,Ashfaq Ahmad,Syed Muhammad Usman Shah,Sanaa Mahmoud Metwally Shanab,Hamdy Elsayed Ahmed Ali,Mervat Aly Mohamed Abo-State,Mohd Fariduddin Othman 한국생물공학회 2016 Biotechnology and Bioprocess Engineering Vol.21 No.2
Increased demand for energy worldwide has resulted in increasing interest in alternative renewable sources of biofuels. Demand for improved systems of bioenergy generation, environmental remediation, and coproduction of high value bioactive compounds has led to the potential use of algae in biomass utilization. In Malaysia, palm oil industries generate high amount of solid wastes. Palm Oil Mill Effluent (POME) is estimated to be three times of the amount of crude palm oil produced. POME is a heavily polluting wastewater due to its high chemical oxygen demand (COD), high biochemical oxygen demand (BOD), and high contents of minerals such as nitrogen and phosphorus that can cause severe pollution to the environment and water resources. A combination of wastewater treatment and renewable bioenergy co-generation with recovery of high-value biochemicals would benefit the palm oil industry.
Study of Workpiece Vibration in Powder-Suspended Dielectric Fluid in Micro-EDM Processes
Gunawan Setia Prihandana,Muslim Mahardika,Mohd Hamdi,Yoke San Wong,Norihisa Miki,Kimiyuki Mitsui 한국정밀공학회 2013 International Journal of Precision Engineering and Vol. No.
Abstract. In micro-EDM (electrical discharge machining), improper removal of debris causes short-circuiting between a tool electrode and a workpiece and in turn, prevents continuous machining process. Therefore, a remarkably longer period of time is required to fabricate a through hole than that would be required when no short-circuiting took place. In order to solve this problem, the dielectric fluid is immersed with graphite nano powders to reduce machining time and improve surface quality due to the less frequent of arcing between the tool electrode and the workpiece. However, excess powders become debris and subsequently deteriorate the efficiency of machining. To fully exploit the effects of the suspended powders, we introduced vibration of the workpiece in order to remove the debris in the small gap between the workpiece and electrode efficiently. The experimental results showed that combination of these techniques improved machining stability, assured continuous machining processes, and significant reduction of the machining time. Reduction of the machining time and the surface roughness of the workpiece after machining were investigated with respect to the powder concentrations when the workpiece was vibrated at 1000 Hz.
Surface Hardness Prediction of CrN Thin Film Coating on AL7075-T6 Alloy Using Fuzzy Logic System
Erfan Zalnezhad,Ahmed Aly Diaa Mohammed Sarhan,Mohd Hamdi 한국정밀공학회 2013 International Journal of Precision Engineering and Vol. No.
In recent years, CrN coating has been identified as one of the most promising protective layers on surfaces of tools and dies due to its excellent mechanical properties, corrosion resistance, and surface hardness. This study presents the predicting of chromium nitride (CrN) coating surface hardness on AL7075-T6 using fuzzy logic technique. First, Al7075-T6 was coated with CrN at different parameter conditions, after which the surfaces hardness of the CrN-coated specimens was measured using a micro hardness machine. Next, a fuzzy logic model was established to predict the surface hardness of CrN coating on AL7075-T6 with respect to changes in input process parameters, DC power, temperature, and nitrogen flow rate based on the trained data obtained from the micro hardness test. Three membership functions were allocated in connection with each model input. Finally, five new experimental tests were carried out to verify the predicted results achieved via the fuzzy logic model. The results indicate an agreement between the fuzzy model and experimental results with 94.664% accuracy.
Erfan Zalnezhad,Ahmed Aly Diaa Mohammed Sarhan,Mohd Hamdi 한국정밀공학회 2012 International Journal of Precision Engineering and Vol. No.
In this research work, predicting of titanium nitride (TiN) coating adhesion on AL7075-T6 is presented. First TiN was coated on Al7075-T6 in different conditions and the surfaces adhesion of TiN coated specimens were measured using micro scratch force machine. Second a fuzzy logic model was established to predict the of TiN coating adhesion on AL7075-T6with respect to changes in input process parameters, DC power, DC bias voltage, and nitrogen flow rate based on the tried data obtained from the scratch force test. Four membership functions are allocated to be connected with each input of the model. Third, new five experimental tests were carried out to verify the predicted results achieved via fuzzy logic model. The result indicated settlement between the fuzzy model and experimental results with the 95.534% accuracy.
Nik Masmiati Nik Pa,Ahmed Aly Diaa Sarhan,Mohd Hamdi Abd Shukor 한국정밀공학회 2012 International Journal of Precision Engineering and Vol. No.
The 2.5D cutting operations are intended for creating NC programs for components with pockets, lugs, flat sections etc, for which,it is too time consuming to produce a 3D volume model of the component. A 2.5D machining processes can perform the cutting operation only in two of the three axes at a time, the movement of the cutter on the main planes before moves to the next depth produced a terrace-like approximation of the required shape. However, adopting the right cutting parameters could be an ideal solution to improve the product quality. This study focused on optimizing the cutting parameters for higher surface quality in 2.5D cutting utilizing titanium coated carbide ball end mill. These parameters include; machined surface inclined angle, axial depth of cut,spindle speed and feed rate. Taguchi optimization method is the most effective method to optimize the cutting parameters, in which the most significant response variables could be identified. The standard orthogonal array of L9 (34) is used, while the signal to noise (S/N), target performance measurement (TPM) response analysis and analysis of variance (Pareto ANOVA) methods are carried out to determine which parameters are statistically significant. Finally, confirmation tests are carried out to investigate the optimization improvements.
Thilagavathi Thiyagarajan,Venugopal Deivasigamani,Marnadu Raj,Chandrasekaran Joseph,Thangaraju Dheivasigamani,Baskaran Palanivel,Mohamed S. Hamdy,Mohd. Shkir 한국화학공학회 2021 Korean Journal of Chemical Engineering Vol.38 No.5
Pure tungsten oxide (WO3) nanoparticles (NPs) and WO3/copper tungstate (CuWO4) nanocomposites (NCs) were prepared by varying copper content from (5-20 wt%) via the co-precipitation process. XRD results reveal that the structural parameters of WO3/CuWO4 NCs have been strongly affected via Cu doping. Morphology of synthesized WO3 was noticed to be distinct and particle size was significantly reduced through Cu doping confirmed by employing HRTEM studies. Elemental purity of as synthesized products, elucidated from EDX and XPS analyses, reveals that WO3/CuWO4 nanocomposites contain W, O and Cu elements only. Also, FT-IR spectra and its corresponding assignments indicate the existence of WO3/CuWO4. UV-Visible study shows that WO3/CuWO4 composites have narrow bandgap compared to pure WO3. Photoluminescence spectral peaks intensity of NCs displays a decreasing trend, which supports the enhanced photocatalytic activity. The results clearly show that 20 wt% Cu incorporated WO3 sample exhibits better photocatalytic nature than that of pure WO3 and will be more applicable in purify the water.