Browsing by Subject "Microstructure"

Article

Application of the Sharp Front Model to capillary absorption in a vuggy limestone

Ioannou, Ioannis; Andreou, Andronikoulla; Tsikouras, Basilios; Hatzipanagiotou, Konstantin (2009)

The unusual pore size distribution and in particular the presence of large pores in certain construction materials, results in an anomalous sorptivity and a marked deviation from the standard t1/2 law. In this paper, we ...

Article

Brownian-like kinematics of ball milling for particulate structural modeling

Doumanidis, C. C.; Kaabi, H. A. Al; Alzaabi, A. S. M.; Gunduz, I. E.; Rebholz, Claus; Doumanidis, C. C. (2016)

Ball milling motion has been previously studied through computationally expensive, off-line experimental video processing and numerical simulations by the discrete element method. This research establishes a more efficient ...

Article

Capillary absorption of water and n-decane by autoclaved aerated concrete

Ioannou, Ioannis; Hamilton, Andrea; Hall, Christopher (2008)

An autoclaved aerated concrete was one of three construction materials used in the round-robin study of hygral properties carried out in the European Commission funded Heat, Air and Moisture Standards Development [HAMSTAD] ...

Article

Cationic telechelic polyelectrolytes: Synthesis by group transfer polymerization and self-organization in aqueous media

Gotzamanis, G. T.; Tsitsilianis, C.; Hadjiyannakou, Stella C.; Patrickios, Costas S.; Lupitskyy, R.; Minko, S. (2006)

ABA triblock copolymers comprising a relative long poly(2-(dimethylamino) ethyl methacrylate) end-capped by short poly(methyl methacrylate) blocks (PMMA-b-PDMAEMA-b-PMMA) were synthesized using group transfer polymerization ...

Article

Characterisation and tribological evaluation of nitrogen-containing molybdenum-copper PVD metallic nanocomposite films

Joseph, M. C.; Tsotsos, C.; Baker, M. A.; Kench, P. J.; Rebholz, Claus; Matthews, A.; Leyland, A. (2005)

This paper reports on the structural, mechanical and tribological properties of molybdenum-copper nanocomposite films 'doped' with small amounts of nitrogen, which contain either no nitride phase (i.e. the nitrogen is held ...

Article

Continuum model for the phase behavior, microstructure, and rheology of unentangled polymer nanocomposite melts

Stephanou, Pavlos S.; Mavrantzas, V. G.; Georgiou, Georgios C. (2014)

We introduce a continuum model for polymer melts filled with nanoparticles capable of describing in a unified and self-consistent way their microstructure, phase behavior, and rheology in both the linear and nonlinear ...

Article

Deposition and characterization of nitrogen containing stainless steel coatings prepared by reactive magnetron sputtering

Schneider, J. M.; Rebholz, Claus; Voevodin, A. A.; Leyland, A.; Matthews, A. (1996)

Nitrogen containing austenitic stainless steel coatings were deposited with nitrogen concentrations up to 14.1 at% using electron enhanced closed field unbalanced DC magnetron sputtering. The reactive gas flow was controlled ...

Article

Effect of antimony-doping and germanium on the highly efficient thermoelectric Si-rich-Mg2(Si,Sn,Ge) materials

Vlachos, N.; Polymeris, G. S.; Manoli, M.; Hatzikraniotis, E.; Khan, A. U.; Lioutas, C. B.; Stefanaki, E. C.; Pavlidou, E.; Paraskevopoulos, K. M.; Giapintzakis, John; Kyratsi, Theodora (2017)

Two series of materials (a) Mg2Si0.55-ySn0.4Ge0.05Sby, 0 ≤ y ≤ 0.0175 and (b) Mg2Si0.5875-xSn0.4GexSb0.0125, 0 ≤ x ≤ 0.20 have been developed and studied in terms of structural features and thermoelectric properties/performance. ...

Article

Effect of microstructure on the thermoelectric performance of La1−xSrxCoO3

Viskadourakis, Z.; Athanasopoulos, G. I.; Kasotakis, E.; Giapintzakis, John (2016)

We present a case where the microstructure has a profound effect on the thermoelectric properties of oxide compounds. Specifically, we have investigated the effect of different sintering treatments on La1−xSrxCoO3 samples ...

Article

Electron spectroscopic studies of nanocomposite PVD TiAlBN coatings

Baker, M. A.; Rebholz, Claus; Leyland, A.; Matthews, A. (2002)

A range of TiAlBN coatings have been deposited by electron beam evaporation and the optimised composition exhibits a 150% improvement over single phase TiAlN coatings in drilling tests. The coatings have been analysed by ...

Article

Macro and Micro-Scale Features of Thermoelectric PbTe (Br, Na) Systems: Micro-FTIR Spectroscopy, Micro-Seebeck Measurements, and SEM/EDX Observations

Stefanaki, E. C.; Polymeris, G. S.; Nikolic, P. M.; Papageorgiou, C.; Pavlidou, E.; Hatzikraniotis, E.; Kyratsi, Theodora; Paraskevopoulos, K. M. (2014)

In this work, n-type and p-type PbTe doped with Br and Na, respectively, were thoroughly examined to determine the effect of the dopant on microstructure. Macro and micro homogeneity of the samples were studied by means ...

Article

Magnetic properties of Fe3O4 thin films grown on different substrates by laser ablation

Paramês, M. L.; Viskadourakis, Z.; Rogalski, M. S.; Mariano, J.; Popovici, N.; Giapintzakis, John; Conde, O. (2007)

Magnetite thin films have been grown onto (1 0 0)Si, (1 0 0)GaAs and (0 0 0 1)Al2O3, at substrate temperatures varying from 473 to 673 K, by UV pulsed laser ablation of Fe3O4 targets in reactive atmospheres of O2 and Ar, ...

Article

Mechanics and energetics modeling of ball-milled metal foil and particle structures

Aureli, M.; Doumanidis, C. C.; Gunduz, I. E.; Hussien, A. G. S.; Liao, Y.; Rebholz, Claus; Doumanidis, C. C. (2017)

The reported research establishes a semi-analytical computational predictive model of fractal microstructure in ball-milled metal foils and powder particulates, with emphasis on its transformation mechanics via an energy-based ...

Conference Object

Microstructure, mechanical and tribological properties of reactive magnetron sputtered titanium carbide coatings

Polychronopoulou, K.; Rebholz, Claus; Theodorou, L.; Böbel, K.; Demas, N. G.; Polycarpou, A. A. (Affiliation: Dept. of Mechanical and Manufacturing Engineering, University of Cyprus, 1678, Nicosia, CyprusAffiliation: Dept. PA-ATM01/SGP21, Engineering Process Technology, Robert Bosch GmbH, Postfach 300220, 70442 Stuttgart, GermanyAffiliation: Dept. of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United StatesCorrespondence Address: Polycarpou, A. A.Dept. PA-ATM01/SGP21, Engineering Process Technology, Robert Bosch GmbH, Postfach 300220, 70442 Stuttgart, Germanyemail: polycarp@uiuc.edu, 2008)

This study describes the correlation between the microstructure, mechanical and tribological properties of Ti 1-xCx coatings (with x being in the range of 0-0.5), deposited by reactive magnetron sputtering from a Ti target ...

Article

Microstructure-based, multiscale modeling for the mechanical behavior of hydrated fiber networks

Barocas, V. Η; Chandran, P. L.; Stylianopoulos, T. (2008)

A multiscale formulation is derived for the mechanics of a dilute fiber network microstructure, as occurs in in vitro reconstituted collagen gels, to accommodate the deterministic solution of a uniform-stress condition in ...

Article

Multiscale modelling of solid tumour growth: the effect of collagen micromechanics

Wijeratne, P. A.; Vavourakis, V.; Hipwell, J. H.; Voutouri, C.; Papageorgis, P.; Stylianopoulos, T.; Evans, A.; Hawkes, D. J. (2016)

Here we introduce a model of solid tumour growth coupled with a multiscale biomechanical description of the tumour microenvironment, which facilitates the explicit simulation of fibre–fibre and tumour–fibre interactions. ...

Article

Multiscale, structure-based modeling for the elastic mechanical behavior of arterial walls

Barocas, V. Η; Stylianopoulos, T. (2007)

Passive elastic behavior of arterial wall remains difficult to model. Although phenomenological and structural models exist, the question of how the three-dimensional network structure of the collagen in the artery determines ...

Article

Nanostructure, mechanical and tribological properties of reactive magnetron sputtered TiCx coatings

Polychronopoulou, K.; Rebholz, Claus; Baker, M. A.; Theodorou, L.; Demas, N. G.; Hinder, S. J.; Polycarpou, A. A.; Doumanidis, C. C.; Böbel, K. (2008)

This study describes the correlation between microstructure, mechanical and tribological properties of TiCx coatings (with x being in the range of 0-1.4), deposited by reactive magnetron sputtering from a Ti target in ...

Conference Object

Numerical simulation of injection mold filling for semi-solid materials

Ahmed, Alauddin; Alexandrou, Andreas N. (ASME, 1995)

Processing of metals and metal matrix composites in the semi-solid state is an emerging new technology and is becoming increasingly popular. This method provides several advantages over the traditional liquid state processing ...

Article

Reduction of spin injection efficiency by interface defect spin scattering in ZnMnSe/AlGaAs-GaAs spin-polarized light-emitting diodes

Stroud, R. M.; Hanbicki, A. T.; Park, Y. D.; Kioseoglou, G.; Petukhov, A. G.; Jonker, B. T.; Itskos, Grigorios; Petrou, Athos Chariton (2002)

The effects of the interface microstructure on spin-injection efficiency in Zn1-xMnxSe/AlyGa1-yAs-GaAs spin-polarized light-emitting diodes (spin-LEDs) were studied. It was shown that the quantum well (QW) spin polarization ...