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Full-Text Articles in Nanoscience and Nanotechnology

Energetic And Entropic Elasticity Of Nonisothermal Flowing Polymers: Experiment, Theory, And Simulation, T. C. Ionescu, B. J. Edwards, David Keffer, V. G. Mavrantzas Jan 2008

Energetic And Entropic Elasticity Of Nonisothermal Flowing Polymers: Experiment, Theory, And Simulation, T. C. Ionescu, B. J. Edwards, David Keffer, V. G. Mavrantzas

Faculty Publications and Other Works -- Chemical and Biomolecular Engineering

The thermodynamical aspects of polymeric liquids subjected to nonisothermal flow are examined from the complementary perspectives of theory, experiment, and simulation. In particular, attention is paid to the energetic effects, in addition to the entropic ones, that occur under conditions of extreme deformation. Comparisons of experimental measurements of the temperature rise generated under elongational flow at high strain rates with macroscopic finite element simulations offer clear evidence of the persistence and importance of energetic effects under severe deformation. The performance of various forms of the temperature equation are evaluated with regard to experiment, and it is concluded that the standard …


Removal Of Organic Dyes From Industrial Wastewaters Using Uv/H2o2, Uv/H2o2/Fe (Ii), Uv/H2o2/Fe (Iii) Processes (Persian Paper), Mir Saeed Seyed Dorraji Jan 2008

Removal Of Organic Dyes From Industrial Wastewaters Using Uv/H2o2, Uv/H2o2/Fe (Ii), Uv/H2o2/Fe (Iii) Processes (Persian Paper), Mir Saeed Seyed Dorraji

Mir saeed Seyed Dorraji

UV/H2O2, UV/H2O2/Fe (II) and UV/H2O2/Fe (III) processes are very effective in removing pollutants from wastewater and can be used for treatment of dyestuff units wastewaters. In this study, Rhodamine B was used as a typical organic dye. Rhodamine B has found wide applications in wax, leather, and paper industries. The results from this study showed that this dye was degradable in the presence of hydrogen peroxide under UV-C irradiation (30W mercury light) and Photo-Fenton process. The dye was resistant to UV irradiation. In the absence of UV irradiation, the decolorization efficiency was very negligible in the presence of hydrogen. Theeffects …


Supercritical Water Oxidation Process And Its Application In Treatment Of Industrial Wastewater (Persian Paper), N. Daneshvar, S. Aber, Mir Saeed Seyed Dorraji, M. Zarei, M. H. Rasoulifard Jan 2008

Supercritical Water Oxidation Process And Its Application In Treatment Of Industrial Wastewater (Persian Paper), N. Daneshvar, S. Aber, Mir Saeed Seyed Dorraji, M. Zarei, M. H. Rasoulifard

Mir saeed Seyed Dorraji

In the last two decades, supercritical water has become an interesting medium for chemistry. One of its most investigated applications is the oxidative treatment of aqueous wastes containing organic compound in the so-called “supercritical water oxidation”. In this technology, supercritical water acts as a non-polar solvent. Consequently, even non-polar organic compounds and gases like oxygen become completely miscible with the supercritical fluid. During the supercritical water oxidation (SCWO) process, the organic compounds react completely with oxidant –mostly oxygen- in a single phase reaction forming CO2 and H2O. The hetero-atoms present in the organic wastes are transformed into the mineral acids. …


Atomistic Simulation Of Energetic And Entropic Elasticity In Short-Chain Polyethylenes, David Keffer, T. C. Ionescu, V. G. Mavrantzas, B. J. Edwards Jan 2008

Atomistic Simulation Of Energetic And Entropic Elasticity In Short-Chain Polyethylenes, David Keffer, T. C. Ionescu, V. G. Mavrantzas, B. J. Edwards

David Keffer

The thermodynamical aspects of polymeric liquids subjected to uniaxial elongational flow are examined using atomistically detailed nonequilibrium Monte Carlo simulations. In particular, attention is paid to the energetic effects, in addition to the entropic ones, which occur under conditions of extreme deformation. Atomistic nonequilibrium Monte Carlo simulations of linear polyethylene systems, ranging in molecular length from C24 to C78 and for temperatures from 300 to 450 K, demonstrate clear contributions of energetic effects to the elasticity of the system. These are manifested in a conformationally dependent heat capacity, which is significant under large deformations. Violations of the hypothesis …


Energetic And Entropic Elasticity Of Nonisothermal Flowing Polymers: Experiment, Theory, And Simulation, David Keffer, T. C. Ionescu, B. J. Edwards, V. G. Mavrantzas Jan 2008

Energetic And Entropic Elasticity Of Nonisothermal Flowing Polymers: Experiment, Theory, And Simulation, David Keffer, T. C. Ionescu, B. J. Edwards, V. G. Mavrantzas

David Keffer

The thermodynamical aspects of polymeric liquids subjected to nonisothermal flow are examined from the complementary perspectives of theory, experiment, and simulation. In particular, attention is paid to the energetic effects, in addition to the entropic ones, that occur under conditions of extreme deformation. Comparisons of experimental measurements of the temperature rise generated under elongational flow at high strain rates with macroscopic finite element simulations offer clear evidence of the persistence and importance of energetic effects under severe deformation. The performance of various forms of the temperature equation are evaluated with regard to experiment, and it is concluded that the standard …