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Social and Behavioral Sciences Commons

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Engineering

2013

1

Articles 1 - 5 of 5

Full-Text Articles in Social and Behavioral Sciences

Alternative Al Production Methods: Part 1 - A Review Of Indirect Carbothermal Routes, M A. Rhamdhani, M A. Dewan, G A. Brooks, B J. Monaghan, L Prentice Jan 2013

Alternative Al Production Methods: Part 1 - A Review Of Indirect Carbothermal Routes, M A. Rhamdhani, M A. Dewan, G A. Brooks, B J. Monaghan, L Prentice

Faculty of Engineering and Information Sciences - Papers: Part A

The production of Al from its ores at present relies on the Bayer (alumina production) and the Hall- Heroult (Al production) process. The cost associated with alumina production and apparent disadvantages of the Hall-Heroult process have led to intensive research to find alternative routes for Al production. The direct carbothermal reduction process has been thoroughly investigated as an alternative technique. Another alternative includes the indirect carbothermal reduction route where alumina (or aluminous ores) is first reduced to intermediate Al compounds before reduced further to Al. The present study reviews and provides systematic thermodynamic analyses of alternative Al production routes. In …


A Simple Model To Extend 1-D Hydraulics To 3-D Hydraulics, Shu-Qing Yang Jan 2013

A Simple Model To Extend 1-D Hydraulics To 3-D Hydraulics, Shu-Qing Yang

Faculty of Engineering and Information Sciences - Papers: Part A

the core of fluid mechanics is the study of friction on a solid/liquid interface, the friction force can be divided into skin friction and form drag. Nikuradse's experiments reveal that the friction factor depends on the Reynolds number (Re) and relative roughness (r), this observation implies the co-existence of skin friction and form drag, but the definitions of Re and r given by Nikuradse cannot be linked with the skin friction and form drag, this leads to the invalidity of existing theory to predict the friction factor in a complex flow, like a channel flow with vegetation. To establish a …


Optimal Design Of An Ultrasmall Soi-Based 1 X 8 Flat-Top Awg By Using An Mmi, Hongqiang Li, Yaoting Bai, Xiaoyi Dong, Enbang Li, Yang Li, Yu Liu, Wenqian Zhou Jan 2013

Optimal Design Of An Ultrasmall Soi-Based 1 X 8 Flat-Top Awg By Using An Mmi, Hongqiang Li, Yaoting Bai, Xiaoyi Dong, Enbang Li, Yang Li, Yu Liu, Wenqian Zhou

Faculty of Engineering and Information Sciences - Papers: Part A

Four methods based on a multimode interference (MMI) structure are optimally designed to flatten the spectral response of silicon-on-insulator- (SOI-) based arrayed-waveguide grating (AWG) applied in a demodulation integration microsystem. In the design for each method, SOI is selected as the material, the beam propagation method is used, and the performances (including the 3 dB passband width, the crosstalk, and the insertion loss) of the flat-top AWG are studied. Moreover, the output spectrum responses of AWGs with or without a flattened structure are compared. The results show that low insertion loss, crosstalk, and a flat and efficient spectral response are …


A Joint Theoretical And Experimental Study For Elastic Electron Scattering From 1,4-Dioxane, P Palihawadana, J P. Sullivan, S J. Buckman, Z Masin, J D. Gorfinkiel, F Blanco, G Garcia, M J. Brunger Jan 2013

A Joint Theoretical And Experimental Study For Elastic Electron Scattering From 1,4-Dioxane, P Palihawadana, J P. Sullivan, S J. Buckman, Z Masin, J D. Gorfinkiel, F Blanco, G Garcia, M J. Brunger

Faculty of Engineering and Information Sciences - Papers: Part A

We present results of measurements and calculations of elastic electron scattering from 1,4-dioxane in the energy range of 0–1000 eV. Absolute differential and integral elastic cross sections have been measured using a crossed electron-molecule beam spectrometer and the relative flow technique, at four energies in the 10–30 eV range and for scattered electrons in the angular range 20◦–129◦. The measured cross sections are compared with results from R-matrix computations, at the static exchange plus polarization level, calculated at energies between 0–20 eV, and with calculations employing the independent atom model with the screening corrected additivity rule (IAM-SCAR). Those latter computations …


Cross-Section Calculations For Positron Scattering From Pyrimidine Over An Energy Range From 0.1 To 10000 Ev, A G. Sanz, M C. Fuss, F Blanco, Z Masin, J D. Gorfinkiel, R P. Mceachran, M J. Brunger, G Garcia Jan 2013

Cross-Section Calculations For Positron Scattering From Pyrimidine Over An Energy Range From 0.1 To 10000 Ev, A G. Sanz, M C. Fuss, F Blanco, Z Masin, J D. Gorfinkiel, R P. Mceachran, M J. Brunger, G Garcia

Faculty of Engineering and Information Sciences - Papers: Part A

We report a computational investigation of positron scattering by pyrimidine (C4H4N2) in the gas phase. Integral and differential cross sections have been calculated over a broad energy range by employing two distinct ab initio quantum scattering methods: the R-matrix method and a corrected form of the independent-atom representation, at low and high energies, respectively. Since pyrimidine is a strong polar molecule further dipole-induced excitations have been calculated in the framework of the first Born approximation. Good agreement is found between the different computational models and fair agreement is found with prior experimental results.