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Nanoparticle (NP) dispersion in engineering fluids holds significant characteristics that impact the quality and performance of liquid fluidic systems, like in biomedical fluids, contaminated water system, heat and energy transfer applications. This paper investigates the dispersal dynamics of metal oxide NPs in the aqueous fluid using large-scale Atomic/Molecular Parallel Simulator by applying CuO NPs as a targeting material with water (H 2 O). Two major parameters were chosen for evaluating the actual system in the simulation: (a) Discrete particle dynamics (DPD) and (b) Charged optimized many body (COMB) potential. In comparison to the experimental results, the current molecular dynamics (MD) simulation results show good correlations with the actual MD viscosity as 2.44 mPas at 313 K. The outcomes of this study were compared with the reference study of Loya et al., i.e. CuO-water nanofluid dispersion using DPD and smoothed particle hydrodynamics that demonstrated a marginal variation between both studies. Graphical Abstract The current research investigates viscosity, diffusion coefficient and radial distribution function with implementation of COMB potential on CuO-H 2 O dispersion.

Date of Acceptance: 29/12/2014Antibacterial Cu bearing stainless steels (CuSS) have been developed recently and their performance has attracted significant attention widely in biomedical, healthcare and environmental facilities in cross-disciplines. The antibacterial ability and its efficiency of the CuSS are associated to the rate and concentration of Cu2z ions releases from its surface. The surface properties such as corrosion resistance are also influenced by the amount and the rate of Cu ions released. Thus, the aim of this study focused on the determination of trace release amount of Cu2+ ions from a typical copper bearing 304 stainless steel (304CuSS). Meanwhile, the release of other key elements in the material such as Cr, Fe, Ni were also examined, and found these multiple elemental releases produced a highly synergistic effect on killing bacterium. The release rate of the metals from 304CuSS was conducted by an inductively coupled plasma optical emission spectrometry (ICP-OES). In this study, the commercial 304 stainless steel (304SS) was served as a control material, while the ICP results showed that the Cu2z ions released from 304CuSS were maintained a constant level with a release rate as low as 0?8 ppb/day/cm2. This phenomenon could be explained by a coordinating role or synergistic effects of Cu, Fe, Cr, and Ni ions. XPS surface composition analysis showed a releases contribution results in day 1 and day 14 that the reduction trend of Cu quantities in through of the surface depth of 304CuSS is consistent and comprehensible

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Metal oxide nanoparticles offer great merits over controlling rheological, thermal, chemical and physical properties of solutions. The effectiveness of a nanoparticle to modify the properties of a fluid depends on its diffusive properties with respect to the fluid. In this study, rheological properties of aqueous fluids (i.e. water) were enhanced with the addition of CeO 2 nanoparticles. This study was characterized by the outcomes of simulation and experimental results of nanofluids. The movement of nanoparticles in the fluidic media was simulated by a largescale molecular thermal dynamic program (i.e. LAMMPS). The COMPASS force field was employed with smoothed particle hydrodynamic potential (SPH) and discrete particle dynamics potential (DPD). However, this study develops the understanding of how the rheological properties are affected due to the addition of nanoparticles in a fluid and the way DPD and SPH can be used for accurately estimating the rheological properties with Brownian effect. The rheological results of the simulation were confirmed by the convergence of the stress autocorrelation function, whereas experimental properties were measured using a rheometer. These rheological values of simulation were obtained and agreed within 5 % of the experimental values; they were identified and treated with a number of iterations and experimental tests. The results of the experiment and simulation show that 10 % CeO 2 nanoparticles dispersion in water has a viscosity of 2.0-3.3 mPas.