On the kinetics of micellar polymerization. Acryloylaminoalkanoates case study

Finite element method is the most powerful tool for development and optimization of the metal forming processes. Analysis of titanium alloy critical parts should include the prediction of microstructure since their mechanical and technological properties essentially depend on the type and parameters of the microstructure. The technological process of parts production for aerospace applications is multi-operational and consists of deformation, heating and cooling stages. Therefore, it is necessary to simulate the microstructure evolution to obtain high quality parts. In presented paper FE simulation coupled with microstructure evolution during hot forging of TC11 titanium alloy has been performed by QForm FEM code. Constitutive relationships, friction conditions and microstructure evolution model have been established using the experiments. The kinetics of phase transformations has been described by the Johnson-Mehl-Avrami-Kolmogorov (JMAK) phenomenological model. The approach is illustrated by industrial case study that proved its practical applicability and economic advantages for technology development of titanium alloy critical parts.

Download Full-text

The impact of phosphorus deficiency on nitrification - case study of a biological pretreatment plant for rendering plant effluent

Water Science & Technology ◽

10.2166/wst.1996.0376 ◽

1996 ◽

Vol 34 (1-2) ◽

pp. 229-236 ◽

Cited By ~ 5

Author(s):

O. Nowak ◽

K. Svardal ◽

H. Kroiss

Keyword(s):

Activated Sludge ◽

Nitrogen Removal ◽

Phosphorus Deficiency ◽

Extended Model ◽

Biological Pretreatment ◽

Dynamic Conditions ◽

Low Levels ◽

The Impact ◽

Kinetics Of

The highly concentrated wastewater of a rendering plant (7 g COD/l and 1.1 g TKN/l on average) is biologically pretreated in an activated sludge plant. Due to low loading of this plant, full nitrification and nitrogen removal are generally achieved. In periods of high COD loads, however, the nitrification capacity was substantially reduced. Control analyses revealed extreme phosphorus deficiency and that only nitrite, but no nitrate was formed. An extended model based on the ‘Activated sludge model No. 1’ has been used to investigate the kinetics of nitrification in the case of phosphorus deficiency, the demand for phosphorus under dynamic conditions, as well as the effect of variations in the nitrogen load at low levels of phosphate.

Download Full-text

A GEOCHEMICAL METHOD FOR ASSESSMENT OF THE THERMAL HISTORIES OF SEDIMENTS: A TWO-WELL CASE STUDY FROM THE GIPPSLAND BASIN, AUSTRALIA

The APPEA Journal ◽

10.1071/aj90025 ◽

1991 ◽

Vol 31 (1) ◽

pp. 325 ◽

Cited By ~ 3

Author(s):

R. Alexander ◽

P.G. Kralert ◽

R. Marzi ◽

R.I. Kagi ◽

E J. Evans

Keyword(s):

Heat Flow ◽

Stable Phase ◽

Carbon Preference Index ◽

Preference Index ◽

History Of ◽

Thermal Histories ◽

Gippsland Basin ◽

Geochemical Method ◽

Kinetics Of

The ester content in kerogen is depleted as sediment maturation progresses in a process which has been shown to correlate with change in the carbon preference index (CPI) of the associated soluble organic matter. We have carried out accurate laboratory measurements of the kinetics of the reaction which causes ester depletion in sediments, and we show how this information can be used to assess the thermal history of sediments. Two wells were selected, Grunter-1 and Volador-1, to provide samples from the Latrobe Group in the Gippsland Basin. The CPI values were measured to assess the extent of reaction at points down each well, and these values were then used with the kinetic parameters for the ester depletion process to obtain thermal histories which are consistent with the available maturity information.This treatment enabled the heat flow from 50 Ma to the present to be assessed and it suggests that at both locations a constant low heat flow during the Gippsland stable phase was followed by a gradual increase from the beginning of the Miocene to present-day values.

Download Full-text

Wastewater treatment by infiltration percolation: a case study

Water Science & Technology ◽

10.2166/wst.2000.0014 ◽

2000 ◽

Vol 41 (1) ◽

pp. 77-84 ◽

Cited By ~ 14

Author(s):

V. Mottier ◽

F. Brissaud ◽

P. Nieto ◽

Z. Alamy

Keyword(s):

Vadose Zone ◽

High Water ◽

Faecal Coliforms ◽

Dune Sands ◽

Seaside Resort ◽

Load Monitoring ◽

Oxidation Performance ◽

Kinetics Of ◽

Stock Recovery

A 1700 p.e. pilot infiltration percolation plant treating the sewage of Mazagon, a seaside resort in the South of Spain, is investigated. Primary effluents, intermittently applied over twin 200 m2 infiltration basins, percolate down to the aquifer through unsaturated dune sands. Each application sequence delivers a volume of 0.25 m3 per m2 of infiltration basin. Analyses of the water sampled at five depths ranging from 0.3 to 2.0 m below the infiltration surface show that the oxidation performance of the plant is highly dependent on the applied load. Monitoring the oxygen content in the air phase of the vadose zone allows to determine the kinetics of the oxygen stock recovery and the oxidation capacity of the plant. Disappointing removal of faecal coliforms and streptococci is attributed to high pore water velocities due to infiltration heterogeneity and the high water height applied during each feeding sequence.

Download Full-text