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Title Sinnott, Susan; Mao, Zugang; Lee, Kiho
Year Computational Studies of Molecular Diffusions through Carbon Nanotubes Based membrances (Invited)
Abbreviated Journal Journal Article
Issue 2002 Keywords Computer Modeling in Engineering and Science
Thesis 3
Place of Publication 5 Language 575-587
Original Title
Series Title Nanofluidics is an area that has been under study for some time in zeolites and idea nanoporous systems. Computational studies of the behavior of molecules in nanoporous structures have played an important role in understanding this phenomenon as experimental studies of molecular behavior in nanometer-scale pores are difficult to perform. in this paper computational work to study molecular motion and the separation of molecular mixtures in carbon nanotube systems is reported. The systems examined include organic molecules, such as CH4, C2H6, n-C4H10, and i-c4H10, and inorganic molecules, such as CO2. The interatomic forces in the molecular dynamics simulations are calculated using a classical reactive empirical bond order hydrocarbon potetial coupled to lernard-Jones and coulombic potentials. Molecules moving at thermal velocities corresponding to 300K are predicted to diffuse from areas of high density to areas of low density through the nanotubes. The simulations indicate how the structure and size of molecules and the nanotubes influence molecular diffusion through the nanotubes and the separation of the molecular mixtures. Series Volume
Serial Orig Record
no NU @ z-mao2 @ 198
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Ahmad, Zaki; Ul-Hamid, Anwar; B.J., Abdul-Aleem The corrosion behavior of scandium alloyed Al 5052 in neutral sodium chloride solution Journal Article 2001 Corrosion Science 43 7 1227-1243 Corrosion; Al–Mg–Sc; Age-hardening; Microstructure; Pitting potential; Polarization Alloying with scandium has a strong influence on the strengthening and weight saving characteristics of Al–2.5Mg alloys. Scandium addition (0.1–0.3 wt.%) to Al–2.5Mg alloys does not introduce any appreciable loss in their resistance to corrosion in 3.5 wt.% NaCl. The corrosion behavior of these alloys is not significantly affected by age hardening. Because of a unique combination of outstanding mechanical properties and a good resistance to corrosion Al–Mg alloys containing scandium represent a major improvement over the more familiar Al–Mg alloys. no NU @ karnesky @ 435
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Park, Kyung-Tae; Hwang, Duck-Young; Lee, Young-Kook; Kim, Young-Kuk; Shin, Dong Hyuk High strain rate superplasticity of submicrometer grained 5083 Al alloy containing scandium fabricated by severe plastic deformation Journal Article 2003 Materials Science and Engineering A Mater. Sci. Eng. A 341 1-2 273-281 High strain rate superplasticity; 5083 Al alloy; Scandium; Severe plastic deformation; Ultrafine grains High strain rate superplasticity (HSRS) was obtained in a commercial 5083 Al alloy by introducing a ultrafine grained structure of 0.3 small mu, Greekm through severe plastic deformation and by adding a dilute amount of scandium (Sc) as a microstructure stabilizer. Tensile tests were carried out on the as-processed sample at temperatures of 623–823 K and initial strain rates of 1×10−3–1×100 s−1. The maximum elongation to failure of 740% was obtained at 773 K and 1×10−2 s−1. HSRS of the alloy was attributed to the combined effects of dynamic recrystallization and preservation of fine recrystallized grains by the presence of Sc. The mechanical behavior of the alloy at 773 K was characterized by a sigmoidal behavior in a plot of stress vs strain rate in the double logarithmic scale. The origin of the sigmoidal behavior was discussed in terms of microstructural evolution during superplastic deformation. An examination of the fractured samples revealed that failure occurred in a brittle manner related to cavitation rather than necking. Cavity stringers were formed parallel to the tensile axis by interlinkage of jagged-shaped isolated cavities along grain boundaries aligned to the tensile axis. no NU @ karnesky @ 585
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Park, Kyung-Tae; Lee, Hang-Jae; Lee, Chong Soo; Nam, Won Jong; Shin, Dong Hyuk Enhancement of high strain rate superplastic elongation of a modified 5154 Al by subsequent rolling after equal channel angular pressing Journal Article 2004 Scripta Materialia Scripta Mater. 51 6 479-483 Aluminum alloy; Superplasticity; Equal channel angular pressing; Rolling Subsequent rolling after equal channel angular pressing (ECAP) resulted in a considerable enhancement of the high strain rate superplastic elongation of a modified 5154 Al alloy, compared to that of the alloy subjected to the identical ECAP strain without rolling. The mechanical data revealed that the deformation of the former was governed by grain boundary sliding but that of the latter was dominated by viscous glide. no NU @ karnesky @ 586
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Suh,Dong-Woo; Lee, Sang-Yong; Lee, Kyong-Hwan; Lim, Su-Keun; Oh, Kyu Hwan Microstructural evolution of Al–Zn–Mg–Cu–(Sc) alloy during hot extrusion and heat treatments Journal Article 2004 Journal of Materials Processing Technology 155-156 1330-1336 Scandium; Microstructure; Recovery; Recrystallization The microstructural evolution during hot extrusion and post heat treatment was investigated for two kind of Al–Zn–Mg–Cu–(Sc) alloy and AA7075. The microstructure of as-extruded bar is mainly comprised of recovered structure for all alloys, however, different restoration processes are observed during post heat treatment. For AA7075 and S1, which contains 0.1% Sc with relatively higher Zn and Cu content than S2, recovery still proceeds during the heat treatment, while the recrystallization becomes main restoration process during the heat treatment for S2. The differences in abnormal grain growth and hardening behavior between S1, AA7075 and S2 during the heat treatment are discussed in connection with the restoration processes and resultant microstructures. no NU @ karnesky @ 622
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Lee, Woei-Shyan; Chen, Tao-Hsing Rate-dependent deformation and dislocation substructure of Al–Sc alloy Journal Article 2006 Scripta Materialia Scripta Mater. 54 8 1463-1468 Al–Sc alloy; Strain rate effect; Activation volume; Dislocation High strength aluminum–scandium (Al–Sc) alloy is impacted at strain rates ranging from 1.2 × 103 s−1 to 5.8 × 103 s−1 at room temperature. The deformation behaviour of Al–Sc alloy is highly dependent on the strain rate. A higher strain rate increases the dislocation density, thereby reducing the size of the dislocation cells. no NU @ karnesky @ 653
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Lee, Thomas C. M. ON ALGORITHMS FOR ORDINARY LEAST SQUARES REGRESSION SPLINE FITTING: A COMPARATIVE STUDY Journal Article 2002 Journal of Statistical Computation and Simulation 72 8 647-663 Bivariate smoothing; Generalized cross-validation; Genetic algorithms; Regression spline; Stepwise selection Regression spline smoothing is a popular approach for conducting nonparametric regression. An important issue associated with it is the choice of a ‘‘theoretically best’’ set of knots. Different statistical model selection methods, such as Akaike’s information criterion and generalized cross-validation, have been applied to derive different ‘‘theoretically best’’ sets of knots. Typically these best knot sets are defined implicitly as the optimizers of some objective functions. Hence another equally important issue concerning regression spline smoothing is how to optimize such objective functions. In this article different numerical algorithms that are designed for carrying out such optimization problems are compared by means of a simulation study. Both the univariate and bivariate smoothing settings will be considered. Based on the simulation results, recommendations for choosing a suitable optimization algorithm under various settings will be provided. no NU @ karnesky @ 860
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Ahn, I. S.; Kim, S. S.; Park, M. W.; Lee, K. M. Phase Characteristics of Mechanically Alloyed Al-10wt.%Nb Alloy Journal Article 2000 Journal of Materials Science Letters 19 22 2015-2018 refbase @ user 904
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Chung, S. C.; Han, S. Z.; Lee, H. M.; Kwon, H. S. Coarsening Phenomenon of L1$_2$ Precipitates in Rapidly Solidified Al-3at.%(Ti,V,Zr) System Journal Article 1995 Scripta Metallurgica et Materialia Scripta Metall. Mater. 33 5 687-693 refbase @ user 1028
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Han, S. Z.; Park, S. I.; Huh, J. S.; Lee, Z. H.; Lee, H. M. Lattice Matching of D0$_{23}$ and D0$_{22}$ Phases in Al-6at.%(Ti,V,Zr) Systems Journal Article 1997 Materials Science and Engineering A Mater. Sci. Eng. A 230 1-2 100-106 refbase @ user 1170
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