Modelling of a hybrid culture system with a stationary layer of liquid perfluorochemical applied as oxygen carrier

Abstract A mathematical model of a hybrid culture system supported with a stationary layer of liquid perfluorochemical (PFC) as a source of O2 for cells which grow in the aqueous phase of culture medium has been developed and discussed. The two-substrate Monod kinetics without inhibition effects, i.e. the Tsao-Hanson equation, has been assumed to characterise the biomass growth. The Damköhler number which relates the growth rate to the mass transfer effects has been used to appraise the regime (i.e. diffusion-limited or kinetics) of the whole process. The proposed model predicted accurately previously published data on the submerged batch cultures of Nicotiana tabacum BY-2 heterotrophic cells performed in a culture system supported with a stationary layer of hydrophobic perfluorodecalin as a liquid O2 carrier. Estimated values of the parameters of the model showed that the process proceeded in the kinetics regime and the growth kinetics, not the effects of the mass transfer between aqueous phase and liquid PFC, had essential influence on the growth of biomass.

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On Modeling Heat and Mass Transfer for Vapor Absorption by a Stationary Layer of the Solution with and without Surfactants

Heat Transfer Research ◽

10.1615/heattransres.v38.i6.30 ◽

2007 ◽

Vol 38 (6) ◽

pp. 507-518

Author(s):

V. E. Nakoryakov ◽

N. I. Grigor'eva

Keyword(s):

Mass Transfer ◽

Heat And Mass Transfer ◽

Vapor Absorption ◽

Stationary Layer

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Applying electrohydrodynamic atomization to enhance mass transfer of metal salts from an aqueous phase towards ionic liquids

Journal of Electrostatics ◽

10.1016/j.elstat.2015.11.007 ◽

2016 ◽

Vol 80 ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

Dries Parmentier ◽

Anna Rybałtowska ◽

Jasper van Smeden ◽

Maaike C. Kroon ◽

Jan C.M. Marijnissen ◽

...

Keyword(s):

Mass Transfer ◽

Ionic Liquids ◽

Aqueous Phase ◽

Metal Salts ◽

Electrohydrodynamic Atomization ◽

Enhance Mass

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A Comparison ofNannochloropsis salinaGrowth Performance in Two Outdoor Pond Designs: Conventional Raceways versus the ARID Pond with Superior Temperature Management

International Journal of Chemical Engineering ◽

10.1155/2012/920608 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 40

Author(s):

Braden Crowe ◽

Said Attalah ◽

Shweta Agrawal ◽

Peter Waller ◽

Randy Ryan ◽

...

Keyword(s):

Culture System ◽

Light Exposure ◽

Fatty Acid Content ◽

Integrated Design ◽

Climatic Conditions ◽

Temperature Management ◽

Nannochloropsis Salina ◽

Batch Cultures ◽

Cell Densities ◽

Pond Design

The present study examines how climatic conditions and pond design affect the growth performance of microalgae. From January to April of 2011, outdoor batch cultures ofNannochloropsis salinawere grown in three replicate 780 L conventional raceways, as well as in an experimental 7500 L algae raceway integrated design (ARID) pond. The ARID culture system utilizes a series of 8–20 cm deep basins and a 1.5 m deep canal to enhance light exposure and mitigate temperature variations and extremes. The ARID culture reached the stationary phase 27 days earlier than the conventional raceways, which can be attributed to its superior temperature management and shallower basins. On a night when the air temperature dropped to −9°C, the water temperature was 18°C higher in the ARID pond than in the conventional raceways. Lipid and fatty acid content ranged from 16 to 25% and from 5 to15%, respectively, as a percentage of AFDW. Palmitic, palmitoleic, and eicosapentaenoic acids comprised the majority of fatty acids. While the ARID culture system achieved nearly double the volumetric productivity relative to the conventional raceways (0.023 versus 0.013 g L−1day−1), areal biomass productivities were of similar magnitude in both pond systems (3.47 versus 3.34 g m−2day−1), suggesting that the ARID pond design has to be further optimized, most likely by increasing the culture depth or operating at higher cell densities while maintaining adequate mixing.

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Do organic surface films on sea salt aerosols influence atmospheric chemistry? – a model study

Atmospheric Chemistry and Physics ◽

10.5194/acp-7-5555-2007 ◽

2007 ◽

Vol 7 (21) ◽

pp. 5555-5567 ◽

Cited By ~ 27

Author(s):

L. Smoydzin ◽

R. von Glasow

Keyword(s):

Mass Transfer ◽

Liquid Phase ◽

Gas Phase ◽

Aqueous Phase ◽

Atmospheric Chemistry ◽

Organic Coating ◽

Sea Salt ◽

Tropospheric Chemistry ◽

Special Focus ◽

Sea Salt Aerosols

Abstract. Organic material from the ocean's surface can be incorporated into sea salt aerosol particles often producing a surface film on the aerosol. Such an organic coating can reduce the mass transfer between the gas phase and the aerosol phase influencing sea salt chemistry in the marine atmosphere. To investigate these effects and their importance for the marine boundary layer (MBL) we used the one-dimensional numerical model MISTRA. We considered the uncertainties regarding the magnitude of uptake reduction, the concentrations of organic compounds in sea salt aerosols and the oxidation rate of the organics to analyse the possible influence of organic surfactants on gas and liquid phase chemistry with a special focus on halogen chemistry. By assuming destruction rates for the organic coating based on laboratory measurements we get a rapid destruction of the organic monolayer within the first meters of the MBL. Larger organic initial concentrations lead to a longer lifetime of the coating but lead also to an unrealistically strong decrease of O3 concentrations as the organic film is destroyed by reaction with O3. The lifetime of the film is increased by assuming smaller reactive uptake coefficients for O3 or by assuming that a part of the organic surfactants react with OH. With regard to tropospheric chemistry we found that gas phase concentrations for chlorine and bromine species decreased due to the decreased mass transfer between gas phase and aerosol phase. Aqueous phase chlorine concentrations also decreased but aqueous phase bromine concentrations increased. Differences for gas phase concentrations are in general smaller than for liquid phase concentrations. The effect on gas phase NO2 or NO is very small (reduction less than 5%) whereas liquid phase NO2 concentrations increased in some cases by nearly 100%. We list suggestions for further laboratory studies which are needed for improved model studies.

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