R. Kreczkiuski, I. Neitzel
Faculdade de Telêmaco Borba - FATEB, Telêmaco Borba, Paraná, Brasil
No processo Kraft a madeira é reduzida a uma massa fibrosa. Neste processo são rompidas as ligações entre as estruturas da madeira separando as fibras. Esta operação, denominada de polpação, é realizada em um equipamento denominado de digestor. Este trabalho analisa o comportamento fluidodinâmico interno a um digestor contínuo do tipo Kamyr.
Energy Exchange During Electron Emission from Carbon Nanotubes: Considerations on Tip Cooling Effect and Destruction of the Emitter
M. Dionne, S. Coulombe, and J. Meunier
Department of Chemical Engineering, McGill University, Montreal, Quebec, Canada
Murphy and Good general theory for electron emission from metal surfaces was used to predict the field-emission capabilities of ideal arrays of vertically aligned carbon nanotubes (VACNT). The Nottingham effect was taken into account in order to explain experimental observation of a localized cooling of the VACNT tips during field emission and the total destruction of very short emitters at ...
S. Prabhakar and J. Raynolds
College of NanoScale Science and Engineering, University at Albany, Albany, NY, USA
Non-charge-based logic is the notion that an electron can be trapped and its spin manipulated through application of gate voltages. Numerical simulations of Spin Single Electron Transistors (SSET) at University at Albany, aimed at practical development of post-CMOS concepts and devices is presented. We use COMSOL based multiphysics finite element simulation strategy to solve the Schrö ...
Modeling and Simulation of High Sensitivity CMOS Pressure Sensor Using Free Boundary Circular Diaphragm Embedded on Ring Channel Shaped MOSFET
S. Joy, T. Tom
Rajagiri School of Engineering and Technology, Kochi, Kerala, India
Sensors have diverse applications ranging from medical field to space explorations. They convert physical parameters such as temperature, pressure, humidity etc: - into an electrical output. The discovery of piezoresistivity property of silicon and germanium led to miniaturization of pressure sensors. Improvement in the sensitivity is the major factor to be considered while designing pressure ...
M.H. Poech, M. Weiß, and K. Gruber
Fraunhofer Institute for Silicon Technology, Itzehoe, Germany
Since a couple of years, sintering becomes more and more important for power electronics. To press a semiconductor under high temperature in silver paste on a substrate promises benefits for durability. Tests with semiconductors of different thickness expose some problems. After the cool down, some of them fall slightly from the substrate. Stress in the boundary layer, caused by different ...
Hydro-Mechanical Modelling of Infiltration Test for a Bentonite-Sand Mixture: Model Verification and Parameter Identification
M. Hasal, R. Hrtus, Z. Michalec, R. Blaheta
Institute of Geonics AS CR, Ostrava, Czech Republic
The first aim of our work is to create a hydro-mechanical model (HM) of unsaturated fluid flow in bentonite-sand mixture (BSM) MX-80. The second aim is to validate and calibrate the developed model by using the data from a laboratory infiltration test of BSM. The used multi-physics model combines Richards type unsaturated flow with diffusive vapour flow and (nonlinear) elastic response of the ...
Modeling and Simulation of Membrane Contactor Employed to Strip CO2 from Rich Solvents via COMSOL Multiphysics® - new
N. Ghasem, M. Al-Marzouqi, N. A. Rahim
United Arab Emirates University, Al-Ain, United Arab Emirates
A mathematical model is developed for the stripping of CO2 from rich solvent. The rich solvent (aqueous NaOH) is used in CO2 absorption from natural gas through gas-liquid hollow fiber membrane contactor. The polyvinylidene fluoride (PVDF) hollow fiber membrane was fabricated via thermally induced phase separation techniques. COMSOL Multiphysics software package is used in solving the set of ...
e2v Ltd., Essex, United Kingdom
There is a requirement for an RF (Radiofrequency) industrial dryer that will be capable of dehydrating foodstuff to the correct level after the product has been fried. RF drying should actively target moisture, due to waters high dielectric properties. An industrial dryer can be optimized using modeling to obtain the correct moisture removal rates in the RF drying process. Measurement of the ...
L. Braci, S. Ognier, and S. Cavadias
Laboratoire de Génie des Procédés Plasmas et Traitements de Surfaces, Ecole Nationale Supérieure de Chimie de Paris, University Pierre et Marie Curie, Paris, France
Non-thermal plasma, generated in atmospheric pressure discharges, has been investigated in our laboratory in order to treat highly diluted (300 ppm to 1000 ppm) volatile pollutant. The collision of electrons created in the discharge with atmospheric air, leads to the formation of reactive species that can totally or partially oxidize the pollutants at near ambient temperature. The purpose of the ...
Modeling and Simulation of Dielectric Barrier Discharge Plasma Reactor for Nitrogen Fixation Reaction
B.S. Patil, Q. Wang, V. Hessel, J. Lang
Eindhoven University of Technology, Eindhoven, The Netherlands
Micro Flow Chemistry and Process Technology, Eindhoven University of Technology, Eindhoven, The Netherlands
Innovation Management, Verfahrenstechnik & Engineering, Evonik Industries AG, Hanau-Wolfgang, Germany
Fixed nitrogen is used in many forms ranging from nitric acid to hydrogen cyanide and is used as such for industrial applications. The reactions to produce these products are highly endothermic and favored by high-temperature processing. The most basic route of chemically fixing nitrogen is the direct reaction of nitrogen and oxygen. However, the major challenge is to supply very high ...