Mixing effects on nitrogen and oxygen concentrations and the relationship to mean residence time in a hyporheic zone of a riffle-pool sequence

The correlation between 52 physicochemical parameters and mean residence time (MRT) for 27 drugs used in human and dog were investigated. The physicochemical parameter values calculated provided a basis for deriving a series of arithmetic expressions, which were used to build a mathematical model describing the relationship between them and the MRT values. From the entire set of analyzed parameters, a subset of 14 was identified that contributed to the derivation of an arithmetic expression: [Formula: see text] the value of which is highly correlated with the MRT value in dogs ( P < .001) and allowed prediction of the MRT predicted (MRT(pred)). In humans, no correlation was found that allowed the calculation of MRT(pred). These results indicate that predicting the pharmacokinetics of any specific drug for humans based on pharmacokinetic data obtained in the dog should be undertaken with knowledge of the inherent limitations.

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The relationship between drug input and mean residence time in the body

Biopharmaceutics & Drug Disposition ◽

10.1002/bdd.2510070607 ◽

1986 ◽

Vol 7 (6) ◽

pp. 577-583 ◽

Cited By ~ 4

Author(s):

Meir Bialer ◽

Zee M. Look ◽

B. Michael Silber ◽

Avraham Yacobi

Keyword(s):

Residence Time ◽

Mean Residence Time ◽

The Body ◽

The Relationship

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Precipitation and filtration of zinc, magnesium, copper and aluminium hydroxides

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19823362 ◽

1982 ◽

Vol 47 (12) ◽

pp. 3362-3370

Author(s):

Otakar Söhnel ◽

Eva Matějčková

Keyword(s):

Residence Time ◽

Mean Residence Time ◽

Filtration Resistance ◽

Filtration Pressure ◽

Bed Porosity ◽

The Mean ◽

Filtration Properties

Filtration properties of batchwise precipitated suspensions of Zn(OH)2, Mg(OH)2 and Cu(OH)2 and continuously precipitated Al(OH)3 were studied. For batchwise precipitated suspensions was verified the theoretically predicted dependence of specific filtration resistance on initial supersaturation and for the continuously precipitated Al(OH)3 the relation between the specific filtration resistance and the mean residence time of suspension in the reactor. Dependences were also recorded between the bed porosity and concentration of precipitated solutions, specific filtration resistance and used filtration pressure and the effect of aging of the batchwise precipitated suspension of Mg(OH)2on its filtration properties. The used CST method for determination of filtration characteristics of Zn(OH)2 suspension was also studied.

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Nitrogen use efficiency: does a trade-off exist between the N productivity and the mean residence time within species?

Australian Journal of Botany ◽

10.1071/bt07139 ◽

2008 ◽

Vol 56 (3) ◽

pp. 272 ◽

Cited By ~ 11

Author(s):

Zhi Y. Yuan ◽

Han Y. H. Chen ◽

Ling H. Li

Keyword(s):

Residence Time ◽

Nitrogen Use Efficiency ◽

Mean Residence Time ◽

Negative Relationship ◽

Controlled Experiments ◽

Nitrogen Use ◽

Trade Off ◽

N Supply ◽

Use Efficiency ◽

The Mean

Nitrogen use efficiency (NUE) can be divided into two components, i.e. N productivity (A) and the mean residence time (MRT). Controlled experiments indicate that there is not a trade-off between A and MRT within species, but this theory has not been well tested in field conditions. Here, we studied the A, MRT and NUE of Stipa krylovii Roshev. in a grassland over 4 years of N fertilisation experimentation. The three parameters (A, MRT and NUE) were significantly related to soil N supply and there was a negative relationship between A and MRT within this species (r = –0.775, P < 0.05), i.e. plants with higher A had lower MRT. Our results showed a trade-off between A and MRT within this Stipa species and this observed trade-off was attributed to different responses of A and MRT to soil fertility.

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Roots are key to increasing the mean residence time of organic carbon entering temperate agricultural soils

Global Change Biology ◽

10.1111/gcb.15787 ◽

2021 ◽

Author(s):

Christopher Poeplau ◽

Axel Don ◽

Florian Schneider

Keyword(s):

Organic Carbon ◽

Residence Time ◽

Mean Residence Time ◽

Agricultural Soils ◽

The Mean

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Studies on solid mean residence time in a three-stage gas-solid fluidized bed with downcomer

Korean Journal of Chemical Engineering ◽

10.1007/s11814-010-0455-5 ◽

2011 ◽

Vol 28 (3) ◽

pp. 969-973 ◽

Cited By ~ 3

Author(s):

Chitta Ranjan Mohanty ◽

Bhim Charan Meikap

Keyword(s):

Fluidized Bed ◽

Residence Time ◽

Mean Residence Time

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Struvite recovery from solution containing phosphate(V) and sulphate(VI) ions

Open Chemistry ◽

10.1515/chem-2015-0120 ◽

2015 ◽

Vol 13 (1) ◽

Cited By ~ 1

Author(s):

Nina Hutnik ◽

Anna Kozik ◽

Krzysztof Piotrowski ◽

Andrzej Matynia

Keyword(s):

Product Quality ◽

Constant Temperature ◽

Residence Time ◽

Mean Residence Time ◽

Crystallization Process ◽

Magnesium Ions ◽

Ammonium Ions ◽

Internal Circulation ◽

Mean Size ◽

Type Crystallizer

AbstractThe research results concerning the application of magnesium and ammonium ions for continuous removal of phosphate(V) ions from solution containing 1.0 or 0.20 mass% of PO43– and from 0.10 to 0.50 mass% of SO42– are presented. A continuous struvite MgNH4PO4 × 6H2O reaction crystallization process was carried out both under stoichiometric conditions and using 20% excess of magnesium ions. The research was conducted in a DT MSMPR type crystallizer with internal circulation of suspension driven by a propeller stirrer, in constant temperature 298 K. The pH varied from 9 to 11 and mean residence time of suspension in a crystallizer τ varied from 900 to 3600 s. It was concluded, that sulphate(VI) ions influenced product quality disadvantageously. Depending on process parameter combinations struvite crystals of mean size from ca. 18 to ca. 44 μm and of moderate homogeneity: CV 7–95% were produced. Presence of sulphate(VI) ions favored crystallization of struvite as prismatic crystals, but tubular forms were also identified. The best shaped struvite crystals were produced at relatively low concentration of sulphate(VI) ions, pH 9 and for mean residence time of suspension in a crystallizer elongated up to 3600 s.

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