Ali Abbas
University of Sydney
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Ali Abbas.
Forensic Science International-genetics | 2010
Reza Alaeddini; Simon J. Walsh; Ali Abbas
Forensic DNA identification techniques are principally based on determination of the size or sequence of desired PCR products. The fragmentation of DNA templates or the structural modifications that can occur during the decomposition process can impact the outcomes of the analytical procedures. This study reviews the pathways involved in cell death and DNA decomposition and the subsequent difficulties these present in DNA analysis of degraded samples.
Physical Review Letters | 2007
Santosh Ansumali; I. V. Karlin; S. Arcidiacono; Ali Abbas; N. I. Prasianakis
The exact solution to the hierarchy of nonlinear lattice Boltzmann (LB) kinetic equations in the stationary planar Couette flow is found at nonvanishing Knudsen numbers. A new method of solving LB kinetic equations which combines the method of moments with boundary conditions for populations enables us to derive closed-form solutions for all higher-order moments. A convergence of results suggests that the LB hierarchy with larger velocity sets is the novel way to approximate kinetic theory.
Computers & Chemical Engineering | 2012
Prue Hatcher; Rajab Khalilpour; Ali Abbas
Abstract This paper presents a systematic analysis of optimisation formulations for the LNG process. It focuses on the construction and testing of eight objective functions with an aim to identify the most appropriate formulation. Four objective functions relate to the operational aspect of the LNG process, while four concentrate on the design aspect. It was found that the most effective operation optimisation objective function is the minimisation of the major operating cost, being compressor power ( W s ). For the design objective functions, the minimisation of Net Present Value (NPV) is favoured where no restriction exists on the area available for LNG plant construction while minimising the objective function ( W s – UA ) is favoured in case where a limit on the plant area is imposed. Finally, a methodology is constructed for using both design and operation objective functions over the life of the LNG plant, considering gas field feed profile.
Journal of Pharmaceutical Sciences | 2009
Nanda Gopal Sahoo; Ali Abbas; Zaher Judeh; Chang Ming Li; Kah-Hay Yuen
A modified multifluid nozzle spray drier was used to prepare drug containing microparticles of a poorly water-soluble anti-malarial drug, artemisinin (ART) with the aim of improving its solubility. We investigated the spray drying of ART with maltodextrin (MD) via a full factorial experimental design considering the effect of drying temperature, feed ratio (ART:MD), feed flow rate and pressure on the physical properties and solubility of spray-dried ART. Characterization of the ART powder, spray-dried ART microparticles and spray-dried ART-MD were analyzed by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) and solubility. DSC and XRD studies suggested that the crystallinity of spray-dried particles was decreased with increasing inlet temperatures and flow rate. The particle size of spray-dried ART microparticles was found to be dependent on inlet temperature, flow rate, pressure and feed ratio. The solubility of spray-dried ART particles in composites was markedly increased as compared to commercial ART. A solubility surface-response model was regressed and statistically assessed before elucidating the significant and direct relationships between inlet temperature and feed rate on one hand and solubility on the other. An optimal pressure condition was observed while feed ratio had relatively reduced effect on solubility. The model was also used in an optimization exercise identifying the optimal solubility to be 66.2 +/- 7.17 microg/mL under the calculated spray drying conditions of: inlet temperature = 140 degrees C, feed ratio (ART:MD) = 0.1, feed flow rate = 250 mL h(-1), and pressure = 1.38 bar.
Engineering in Life Sciences | 2015
Muhamad Hafiz Abd Rahim; Hanan Hasan; Alejandro Montoya; Ali Abbas
The use of pure substrate represents a significant proportion of the cost of manufacturing a drug such as lovastatin. This study explores the production of lovastatin and (+)‐geodin by Aspergillus terreus ATCC 20542 using biodiesel‐derived crude glycerol (CG) as a feedstock. Shake flask experiments showed reduced lovastatin production and glycerol consumption in the presence of 10–50 g/L CG with respect to pure glycerol controls. At 50 g/L, lovastatin and (+)‐geodin production was significantly reduced by 82 and 73%, respectively. The lowest lovastatin inhibition was detected in 30 g/L of CG (48%), which was accompanied by a significant rise in (+)‐geodin production (338%). Further investigation was performed on three major impurities found in CG, namely methanol (MeOH), sodium chloride (NaCl), and fatty acids (oleic acid and palmitic acid (PA), soap). None was particularly inhibitory for lovastatin, except soap and PAs, which reduced its production by more than 50% at all concentrations tested. In contrast, (+)‐geodin was inhibited in the presence of MeOH and PA by up to 46 and 91%, respectively. These observations indicate that partial purification of CG would be potentially useful in improving production of lovastatin and (+)‐geodin by A. terreus.
Journal of Computer Applications in Technology | 2006
Ali Abbas; Jose A. Romagnoli
This work features the integrated utilisation of various technologies including advanced modelling software (both off-line and real time), model-predictive control and distributed computer control technology in a collective environment. The outcome will be a structured framework for the optimal control of generic and complex batch recipe-driven processes. This framework is general and well suited for application to any particulate process. The design from a holistic point of view of a multilayer architecture for the advanced control of a batch cooling crystallisation pilot facility is described.
Waste Management | 2017
Hamza Y. Ismail; Ali Abbas; Fouad Azizi; Joseph Zeaiter
This paper presents a simulation flowsheet model of a waste tire pyrolysis process with feed capacity of 150kg/h. A kinetic rate-based reaction model is formulated in a form implementable in the simulation package Aspen Plus, giving the flowsheet model the capability to predict more than 110 tire pyrolysis products as reported in experiments by Laresgoiti et al. (2004) and Williams (2013) for the oil and gas products respectively. The simulation model is successfully validated in two stages: firstly against experimental data from Olazar et al. (2008) by comparing the mass fractions for the oil products (gas, liquids (non-aromatics), aromatics, and tar) at temperatures of 425, 500, 550 and 610°C, and secondly against experimental results of main hydrocarbon products (C7 to C15) obtained by Laresgoiti et al. (2004) at temperatures of 400, 500, 600, and 700°C. The model was then used to analyze the effect of pyrolysis process temperature and showed that increased temperatures led to chain fractions from C10 and higher to decrease while smaller chains increased; this is attributed to the extensive cracking of the larger hydrocarbon chains at higher temperatures. The utility of the flowsheet model was highlighted through an energy analysis that targeted power efficiency of the process determined through production profiles of gasoline and diesel at various temperatures. This shows, through the summation of the net power gain from the plant for gasoline plus diesel that the maximum net power lies at the lower temperatures corresponding to minimum production of gasoline and maximum production of diesel. This simulation model can thus serve as a robust tool to respond to market conditions that dictate fuel demand and prices while at the same time identifying optimum process conditions (e.g. temperature) driven by process economics.
global engineering education conference | 2010
Ali Abbas
Virtual worlds can support learning processes by providing visual aid that deals with the complexities of real life problems. Increasingly useful is the online use of virtual worlds and the associated technical and social interactivity. This paper describes the development of a virtual world in Second Life environment for dynamics and control learning, and outlines the use of this virtual world as a learning space in the elective course Process Systems Engineering. The outcomes based on lecturers experience as well as on evidence from student feedback are reported and recommendations are made for the use of virtual worlds in Engineering education going forward.
Computer-aided chemical engineering | 2012
Zhengxiong Li; Rajab Khalilpour; Ali Abbas
Abstract In this study, we analyze two design configurations for post-combustion carbon capture (PCC) namely inter-stage cooling and split flow. The results show that inter-stage cooling configuration has notable impact on improving PCC performance. It is found that, for a flue gas with 13.0 mol% of CO 2 , and with objective of capturing 90% of CO 2 at purity of 98%, base case configuration imposes a 4.7GJ/ton-CO 2 reboiler duty. This energy burden decreases (about 34.8%) to 3.1 GJ/ton-CO 2 with single-stage cooling configuration. Two-stage-cooling configuration further improves the efficiency but only incrementally. Similarly, split flow design configuration shows considerable improvement in efficiency (3.8GJ/ton-CO 2 vs. 4.7GJ/ton-CO 2 for base case).
Journal of Vacuum Science and Technology | 2016
Tushar M. Shimpi; Jason M. Kephart; Drew E. Swanson; Amit Munshi; W. S. Sampath; Ali Abbas; J.M. Walls
Single phase Cd0.6Zn0.4Te (CdZnTe) films of 1 μm thickness were deposited by radio frequency planar magnetron sputter deposition on commercial soda lime glass samples coated with fluorine-doped tin oxide and cadmium sulphide (CdS). The stack was then treated with cadmium chloride (CdCl2) at different temperatures using a constant treatment time. The effect of the CdCl2 treatment was studied using optical, materials, and electrical characterization of the samples and compared with the as-deposited CdZnTe film with the same stack configuration. The band gap deduced from Tauc plots on the as-deposited CdZnTe thin film was 1.72 eV. The deposited film had good crystalline quality with a preferred orientation along the {111} plane. After the CdCl2 treatment, the absorption edge shifted toward longer wavelength region and new peaks corresponding to cadmium telluride (CdTe) emerged in the x-ray diffraction pattern. This suggested loss of zinc after the CdCl2 treatment. The cross sectional transmission electron mi...