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Effect Of Ion Concentration On Mechanosynthesis Of Carbonated Chlorapatite Nanopowders
Effect Of Ion Concentration On Mechanosynthesis Of Carbonated Chlorapatite Nanopowders
Faculty of Engineering University of Malaya
Carbonated chlorapatite nanopowders (n-CCAp) with different degrees of substitution were successfully synthesized by the one-step mechanochemical process. Results demonstrated that the formation of n-CCAp was influenced strongly by the carbonate content (x). From X-ray analysis, crystallite size, crystallinity degree, and unit cell volume of n-CCAp decreased significantly as carbonate content (x) increased from 0 to 2. Conversely, the lattice strain and the volume fraction of grain boundaries grew considerably. Microscopic analysis showed the average particle size of the synthesized powders was 15 +/- 10 nm. The influence of carbonate concentration on mechanosynthesis of pure n-CCAp utilizing a facile solid-state process …
Effect Of High-Energy Ball Milling On The Formation And Micro Structural Features Of Carbonated Chlorapatite Nanopowders
Faculty of Engineering University of Malaya
Carbonated chlorapatite nanopowders (n-CCAp) were synthesized by mechanochemical process from calcite (CaCO3), phosphorus pentoxide (P2O5), and calcium chloride (CaCl2) as raw materials. Results demonstrated that the formation of n-CCAp was influenced strongly by the milling time. At the beginning of milling (up to 15 min), CaCO3 and CaCl2 were the dominant phases, while P2O5 disappeared entirely due to its very high deliquescent nature. With increasing the milling time to 600 min, the progressive mechanochemical reaction was completed which resulted in the formation of nanostructured carbonated chlorapatite. According to the X-ray diffraction data, crystallite size of the product decreased from 24 …
Effect Of Molybdenum Disulfide Particle Sizes On Wear Performance Of Commercial Lubricant, Innovative Research Publications Irp India, S. M. Muzakkir, Harish Hirani
Effect Of Molybdenum Disulfide Particle Sizes On Wear Performance Of Commercial Lubricant, Innovative Research Publications Irp India, S. M. Muzakkir, Harish Hirani
Innovative Research Publications IRP India
Experimental investigations have been conducted for determination of effectiveness of employing a combination of three particle sizes (40 nm size, 1.75 μm size and 53 μm size) of Molybdenum Disulphide as anti-wear additive in a commercial lubricant. The conformal block and disk configuration has been used to conduct experiments for determination of wear of the sliding surfaces. The performance of the proposed combined particle sizes anti-wear additive is compared with single particle size anti-wear additives to establish its robustness under varying surface conditions.
Too Enthusiastic To Care For Safety: Present Status And Recent Developments Of Nanosafety In Asean Countries
Faculty of Engineering University of Malaya
Nanotechnology has the prospect to vibrate the imagination of human being and has the ability to be used in almost every sector of human need. With its limitless potentials, there are many environmental, health and safety related concerns due to extremely ambivalent effects of nanoparticles. Studies revealed that nanoparticles can enter the human body through the lungs, intestinal tract, and skin. Therefore, the researchers and workers who handle nanoparticles and nanomaterials can theoretically and primarily be affected, whereas on the consumers this will have secondary effects. This paper aims at sharing and evaluating the investment scenario, present status and recent …
Eulerian-Lagrangian Analysis Of Solid Particle Distribution In An Internally Heated And Cooled Air-Filled Cavity
Faculty of Engineering University of Malaya
A parametric study has been conducted to investigate particle deposition on solid surfaces during free convection flow in an internally heated and cooled square cavity filled with air. The cavity walls are insulated while several pairs of heaters and coolers (HACs) inside the cavity lead to free convection flow. The HACs are assumed to be isothermal heat source and sinks with temperatures T-h and T-c (T-h > T-c). The problem is numerically investigated using the Eulerian-Lagrangian method. Two-dimensional Navier-Stokes and energy equations are solved using finite volume discretization method. Applying the Lagrangian approach, 5000 particles, distributed randomly in the enclosure, were …