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University of Wollongong

Growth

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Full-Text Articles in Science and Technology Studies

Simultaneous Grain Growth And Grain Refinement In Bulk Ultrafine-Grained Copper Under Tensile Deformation At Room Temperature, Hai Liang Yu, Cheng Lu, Anh Kiet Tieu, Hui Jun Li, Ajit R. Godbole, Charlie Kong, Xing Zhao Jan 2016

Simultaneous Grain Growth And Grain Refinement In Bulk Ultrafine-Grained Copper Under Tensile Deformation At Room Temperature, Hai Liang Yu, Cheng Lu, Anh Kiet Tieu, Hui Jun Li, Ajit R. Godbole, Charlie Kong, Xing Zhao

Faculty of Engineering and Information Sciences - Papers: Part A

Grain growth and grain refinement behavior during deformation determine the strength and ductility of ultrafine-grained materials. We used asymmetric cryorolling to fabricate ultrafine-grained copper sheets with an average grain width of 230 nm and having a laminate structure. The sheets show a high-true failure strain of 1.5. Observation of the microstructure at the fracture surface reveals that ultrafine laminate-structured grains were simultaneously transformed into both equiaxed nanograins and coarse grains under tensile deformation at room temperature.


Analysis Of A Chemostat Model With Variable Yield Coefficient And Substrate Inhibition: Contois Growth Kinetics, Rubayyi Turki Alqahtani, Mark I. Nelson, Annette L. Worthy Jan 2015

Analysis Of A Chemostat Model With Variable Yield Coefficient And Substrate Inhibition: Contois Growth Kinetics, Rubayyi Turki Alqahtani, Mark I. Nelson, Annette L. Worthy

Faculty of Engineering and Information Sciences - Papers: Part A

2015, Copyright Taylor & Francis Group, LLC. We analyze the steady-state operation of a generalized reactor model that encompasses a continuous flow bioreactor and an idealized continuous flow membrane reactor as limiting cases. The biochemical reaction kinetics is governed by a Contois growth model subject to noncompetitive substrate inhibition with a variable substrate yield coefficient. The steady-state performance of the reactor is predicted and stability of the steady-state solutions as a function of dimensionless residence time reported. Our results identified two cases of practical interest. The first feature corresponds to the case where solutions to both no-washout and washout conditions …


Bacterial Cellulose As A Support For The Growth Of Retinal Pigment Epithelium, Sara Goncalves, Jorge Padrao, Ines P. Rodrigues, J P. Silva, Vitor Sencadas, Senentxu Lanceros-Méndez, Henrique Girao, F Dourado, L R. Rodrigues Jan 2015

Bacterial Cellulose As A Support For The Growth Of Retinal Pigment Epithelium, Sara Goncalves, Jorge Padrao, Ines P. Rodrigues, J P. Silva, Vitor Sencadas, Senentxu Lanceros-Méndez, Henrique Girao, F Dourado, L R. Rodrigues

Faculty of Engineering and Information Sciences - Papers: Part A

The feasibility of bacterial cellulose (BC) as a novel substrate for retinal pigment epithelium (RPE) culture was evaluated. Thin (41.6 ± 2.2 μm of average thickness) and heat-dried BC substrates were surface-modified via acetylation and polysaccharide adsorption, using chitosan and carboxymethyl cellulose. All substrates were characterized according to their surface chemistry, wettability, energy, topography, and also regarding their permeability, dimensional stability, mechanical properties, and endotoxin content. Then, their ability to promote RPE cell adhesion and proliferation in vitro was assessed. All surface-modified BC substrates presented similar permeation coefficients with solutes of up to 300 kDa. Acetylation of BC decreased it's …


Multiplicative Modelling Of Four-Phase Microbial Growth, María Jesús Munoz-Lopez, Maureen P. Edwards, Ulrike Schumann, Robert S. Anderssen Jan 2015

Multiplicative Modelling Of Four-Phase Microbial Growth, María Jesús Munoz-Lopez, Maureen P. Edwards, Ulrike Schumann, Robert S. Anderssen

Faculty of Engineering and Information Sciences - Papers: Part A

Microbial growth curves, recording the four-phases (lag, growth, stationary, decay) of the dynamics of the surviving microbes, are regularly used to support decision-making in a wide variety of health related activities including food safety and pharmaceutical manufacture. Often, the decision-making reduces to a simple comparison of some particular feature of the four-phases, such as the time at which the number of surviving microbes reaches a maximum. Consequently, in order to obtain accurate estimates of such features, the first step is the determination, from experimental measurements, of a quantitative characterization (model) of the four-phases of the growth-decay dynamics involved, which is …


Multiple Semiclassical States For Coupled Schrödinger-Poisson Equations With Critical Exponential Growth, Zhisu Liu, Shangjiang Guo, Yanqin Fang Jan 2015

Multiple Semiclassical States For Coupled Schrödinger-Poisson Equations With Critical Exponential Growth, Zhisu Liu, Shangjiang Guo, Yanqin Fang

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, we study the multiplicity of positive solutions for a class of Schrödinger-Poisson systems. Working in a variational setting, we prove the existence and multiplicity of positive solutions for the system when the Plank's constant is small and the potential satisfies some suitable conditions. We show that the number of positive solutions depends on the profile of the potential and that each solution concentrates around its corresponding global minimum point of the potential in the semi-classical limit. We also study the exponential decay.


A Model For Acid-Mediated Tumour Growth With Nonlinear Acid Production Term, Andrew B. Holder, Marianito R. Rodrigo, Miguel A. Herrero Jan 2014

A Model For Acid-Mediated Tumour Growth With Nonlinear Acid Production Term, Andrew B. Holder, Marianito R. Rodrigo, Miguel A. Herrero

Faculty of Engineering and Information Sciences - Papers: Part A

This article considers a mathematical model for tumour growth based on an acid-mediated hypothesis, i.e. the assumption that tumour progression is facilitated by acidification of the region around the tumour-host interface. The resulting destruction of the normal tissue environment promotes tumour growth. We will derive and analyse a reaction-diffusion model for tumour progression that includes different aspects of pathological and healthy cell metabolism to check tumour growth. Our results can provide insights into the governing dynamics of invasive processes that may suggest possible intervention strategies, leading to the design of new and better experiments or treatments.


Detection Of Crack Growth In Rail Steel Using Acoustic Emission, Andrii Kostryzhev, C L. Davis, C Roberts Jan 2013

Detection Of Crack Growth In Rail Steel Using Acoustic Emission, Andrii Kostryzhev, C L. Davis, C Roberts

Faculty of Engineering and Information Sciences - Papers: Part A

Increased traffic speeds and axle loads on modern railways enhance rail track degradation. To eliminate track failure due to rail defects, a condition monitoring system requires methods for the early detection of defects which grow in service. Acoustic emission (AE) monitoring is the only non-destructive technique which might be applied online to study the defect growth under traffic loading. However, a high level of traffic noise and a limited signal from crack growth, especially at low crack growth rates, significantly complicate the AE signal analysis. In the present work, the AE monitoring of rail steel fatigue was carried out in …


Modelling Microbial Growth In A Closed Environment, Maureen P. Edwards, Ulrike Schumann, Robert S. Anderssen Jan 2013

Modelling Microbial Growth In A Closed Environment, Maureen P. Edwards, Ulrike Schumann, Robert S. Anderssen

Faculty of Engineering and Information Sciences - Papers: Part A

The formulation of models for the growth of microbes (fungi; bacteria) must not only take account of the current number of the microbes but also of the effect of the environment in which the growth is occurring and of the type of measurements used to record the growth. In industrial processes, the effect of physiological (morphological) changes on the growth must be taken into account. When growth is occurring in an open environment which achieves an equilibrium (e.g. balancing growth and harvesting) and is measured as the time evolution of the total number of microbes present (alive and dead), autonomous …


Degradation Of Azo Dye Acid Orange 7 In A Membrane Bioreactor By Pellets And Attached Growth Of Coriolus Versicolour, Faisal I. Hai, Kazuo Yamamoto, Fumiyuki Nakajima, Kensuke Fukushi, Long D. Nghiem, William E. Price, Bo Jin Jan 2013

Degradation Of Azo Dye Acid Orange 7 In A Membrane Bioreactor By Pellets And Attached Growth Of Coriolus Versicolour, Faisal I. Hai, Kazuo Yamamoto, Fumiyuki Nakajima, Kensuke Fukushi, Long D. Nghiem, William E. Price, Bo Jin

Faculty of Engineering and Information Sciences - Papers: Part A

The aim of this study was to systematically compare the degradation of azo dye acid orange 7 by spongy pellets and attached biofilm of Coriolus versicolour (NBRC 9791) in a membrane bioreactor (MBR) under non-sterile conditions. Mild stirring (35 rpm) resulted in spherical (φ = 0.5 cm), spongy pellets and concomitantly triggered high enzymatic activity of the fungus, allowing for excellent decolouration (>99%) of a synthetic wastewater containing the dye. However, bacterial contamination eventually damaged the fungus pellets, leading to decreased decolouration efficiency. Promotion of attached growth on a plastic support along with formation of spherical spongy pellets allowed …


Joint Analysis Of Beef Growth And Carcass Quality Traits Through Calculation Of Co-Variance Components And Correlations., H R. Mirzaei, Arunas P. Verbyla, W. S. Pitchford Jan 2011

Joint Analysis Of Beef Growth And Carcass Quality Traits Through Calculation Of Co-Variance Components And Correlations., H R. Mirzaei, Arunas P. Verbyla, W. S. Pitchford

Faculty of Engineering and Information Sciences - Papers: Part A

A joint growth-carcass model using random regression was used to estimate the (co)variance components of beef cattle body weights and carcass quality traits and correlations between them. During a four-year period (1994-1997) of the Australian "southern crossbreeding project", mature Hereford cows (N = 581) were mated to 97 sires of Jersey, Wagyu, Angus, Hereford, South Devon, Limousin, and Belgian Blue breeds, resulting in 1141 calves. Data included 13 (for steers) and 8 (for heifers) body weight measurements approximately every 50 days from birth until slaughter and four carcass quality traits: hot standard carcass weight, rump fat depth, rib eye muscle …


Prediction Model Of A Joint Analysis Of Beef Growth And Carcass Quality Traits, H R. Mirzaei, Arunas P. Verbyla, Wayne S. Pitchford Jan 2011

Prediction Model Of A Joint Analysis Of Beef Growth And Carcass Quality Traits, H R. Mirzaei, Arunas P. Verbyla, Wayne S. Pitchford

Faculty of Engineering and Information Sciences - Papers: Part A

A joint growth-carcass analysis was conducted to develop equations for predicting carcass quality traits associated with variation in growth path of crossbred cattle. During a four-year period (1994-1997) of the Australian "Southern Crossbreeding Project", mature Hereford cows (r = 581) were mated to 97 sires of Jersey, Wagyu, Angus, Hereford, South Devon, Limousin, and Belgian Blue breeds, resulting in 1141 calves. Data included body weight measurements of steers and heifers from birth until slaughter and four carcass quality traits: hot standard carcass weight, rump fat depth, rib eye muscle area, and intramuscular fat content. The model provides nine outputs: median …


Modeling Of Crossbred Cattle Growth, Comparison Between Cubic And Piecewise Random Regression Models, H R. Mirzaei, Wayne S. Pitchford, Arunas P. Verbyla Jan 2011

Modeling Of Crossbred Cattle Growth, Comparison Between Cubic And Piecewise Random Regression Models, H R. Mirzaei, Wayne S. Pitchford, Arunas P. Verbyla

Faculty of Engineering and Information Sciences - Papers: Part A

Two analyses, cubic and piecewise random regression, were conducted to model growth of crossbred cattle from birth to about two years of age, investigating the ability of a piecewise procedure to fit growth traits without the complications of the cubic model. During a four-year period (1994-1997) of the Australian "Southern Crossbreeding Project", mature Hereford cows (N = 581) were mated to 97 sires of Angus, Belgian Blue, Hereford, Jersey, Limousin, South Devon, and Wagyu breeds, resulting in 1141 steers and heifers born over four years. Data included 13 (for steers) and eight (for heifers) live body weight measurements, made approximately …


Multiplicity Of Solutions For Quasilinear Elliptic Equations With Critical Exponential Growth, Yanqin Fang, Jihui Zhang Jan 2011

Multiplicity Of Solutions For Quasilinear Elliptic Equations With Critical Exponential Growth, Yanqin Fang, Jihui Zhang

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper we consider a system of N-Laplacian elliptic equa- tions with critical exponential growth. The existence and multiplicity re- sults of solutions are obtained by a limit index method and Trudinger- Moser inequality.


Low Temperature Graphene Growth, Shailesh Kumar, N Mcevoy, T. Lutz, G. Keeley, Nicholas Whiteside, Werner Blau, G. Duesberg Jan 2009

Low Temperature Graphene Growth, Shailesh Kumar, N Mcevoy, T. Lutz, G. Keeley, Nicholas Whiteside, Werner Blau, G. Duesberg

Faculty of Engineering and Information Sciences - Papers: Part A

We demonstrate the growth of graphene films on nickel substrates by chemical vapour deposition using acetylene at temperatures as low as 750 degrees celsius, opening a viable route for its scalable production. Raman spectroscopy was used to confirm defect-free mono and multilayer graphene at and above this temperature, and of defective graphene at lower temperatures. Atomic force microscopy and scanning electron microscopy performed directly on the films give an indication of graphene flake size, morphology and also the topography on substrate. An unexpected dependence of graphene thickness on precursor dwell time is reported. This together with low temperature growth suggests …


Values Of Minors Of An Infinite Family Of D-Optimal Designs And Their Application To The Growth Problem, C Koukouvinos, M Mitrouli, Jennifer Seberry Jan 2001

Values Of Minors Of An Infinite Family Of D-Optimal Designs And Their Application To The Growth Problem, C Koukouvinos, M Mitrouli, Jennifer Seberry

Faculty of Engineering and Information Sciences - Papers: Part A

No abstract provided.