EFFECT OF TEMPERATURE ON PHOSPHATE SORPTION AND DESORPTION IN TWO ACID SOILS

Soil Science ◽  
1982 ◽  
Vol 133 (3) ◽  
pp. 160-166 ◽  
Author(s):  
S. H. CHIEN ◽  
N. K. SAVANT ◽  
U. MOKWUNYE
Keyword(s):  
Acid Soils ◽  
Effect Of Temperature ◽  
Phosphate Sorption

Modelling phosphate-sorption kinetics in acid soils

1995 ◽  
Vol 46 (2) ◽  
pp. 239-245 ◽  
Author(s):  
D. FREESE ◽  
W.H. RIEMSDIJK ◽  
S.E.A.T.M. ZEE
Keyword(s):  
Acid Soils ◽  
Sorption Kinetics ◽  
Phosphate Sorption

Phosphorus sorption by acid soils: comparative study of some parameters

1987 ◽  
Vol 109 (1) ◽  
pp. 87-94 ◽  
Author(s):  
J. Arines ◽  
Maria Sainz
Keyword(s):  
Comparative Study ◽  
Buffer Capacity ◽  
Acid Soils ◽  
Phosphorus Sorption ◽  
Sorption Behaviour ◽  
Phosphate Sorption ◽  
North West ◽  
Sorption Parameter ◽  
Best Parameter ◽  
Sorption Parameters

SummaryA comparative study of sorption maxima (simple and double Langmuir equations) and buffer capacity of acid soils was made in order to select the most useful P-sorption parameter. Data were obtained from 20 acid soils from Galicia (north-west Spain) and selection was made by linear and multiple regressions among sorption parameters, and between these and some soil characteristics related to phosphate sorption (clay and organicmatter content, pH in NaF, and 0·5 M-CuCl2-extracted Al).The phosphate buffer capacity, determined by the slope of the regression ‘sorbed-P v. logc’, was the best parameter to represent soil phosphate sorption behaviour. 0·5 M-CuCl2- extracted Al was the edaphic characteristic which best related to sorption properties.

Effect of liming on phosphate sorption by acid soils

1990 ◽  
Vol 41 (1) ◽  
pp. 165-175 ◽  
Author(s):  
R. NAIDU ◽  
J. K. SYERSY ◽  
R. W. TILLMAN ◽  
J. H. KIRKMAN
Keyword(s):  
Acid Soils ◽  
Phosphate Sorption

scholarly journals Kinetics, thermodynamics and mechanisms of phosphate sorption onto bottle gourd biomass modified by (3-chloro-2-hydroxypropyl) trimethylammonium chloride

2019 ◽  
Vol 44 (3) ◽  
pp. 267-285 ◽  
Author(s):  
Dragana Z Marković-Nikolić ◽  
Milorad D Cakić ◽  
Goran Petković ◽  
Goran S Nikolić
Keyword(s):  
Thermodynamic Parameters ◽  
Quaternary Ammonium ◽  
Sorption Kinetics ◽  
Phosphate Removal ◽  
Bottle Gourd ◽  
Effect Of Temperature ◽  
Trimethylammonium Chloride ◽  
Phosphate Sorption ◽  
Maximum Sorption Capacity ◽  
Non Linear

The sorption kinetics and thermodynamic parameters of phosphate removal from aqueous solution using quaternary ammonium–modified bottle gourd biomass as a sorbent were studied in a batch reactor. The cationic sorbent, containing trimethylammonium and hydroxypropyl groups, was obtained through the chemical reactions of the lignocellulosic Lagenaria vulgaris shell with (3-chloro-2-hydroxypropyl)trimethylammonium chloride. Experimental data of phosphate sorption from aqueous solutions of different initial concentrations (5–140 mg P L−1) have been analysed by reaction kinetics and diffusion models. The characteristic rate constants calculated by linear and non-linear regression analyses of the experimental results are presented. The phosphate sorption reaches equilibrium in 20–30 min, depending on the initial phosphate concentration. The maximum sorption capacity of quaternary ammonium–modified bottle gourd (QABG) sorbent was 18 mg P g−1 at 20 oC. The sorption system is best described by a non-linear equation of the pseudo first-order model ( R2 > 0.996). The Weber–Morris model indicated that the sorption process took place in three steps, whereby the intra-particle diffusion is not the only rate-controlling step. In addition, the effect of temperature (20 oC–50 oC) on sorption kinetics was also investigated. The various thermodynamic parameters suggest that phosphate sorption is favoured and is an exothermic process. The activation energy and the sticking probability confirmed that anion exchange is the dominant mechanism. These results provide valuable information for the potential use of agricultural residues in the treatment of wastewaters.

Nucleation of Disorder in Fe3Al Alloys

1967 ◽  
Vol 25 ◽  
pp. 312-313
Author(s):  
P. R. Swann ◽  
W. R. Duff ◽  
R. M. Fisher
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Annealing Temperature ◽  
Antiphase Domain ◽  
Effect Of Temperature ◽  
Domain Structures ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Higher Temperature ◽  
The One

Recently we have investigated the phase equilibria and antiphase domain structures of Fe-Al alloys containing from 18 to 50 at.% Al by transmission electron microscopy and Mössbauer techniques. This study has revealed that none of the published phase diagrams are correct, although the one proposed by Rimlinger agrees most closely with our results to be published separately. In this paper observations by transmission electron microscopy relating to the nucleation of disorder in Fe-24% Al will be described. Figure 1 shows the structure after heating this alloy to 776.6°C and quenching. The white areas are B2 micro-domains corresponding to regions of disorder which form at the annealing temperature and re-order during the quench. By examining specimens heated in a temperature gradient of 2°C/cm it is possible to determine the effect of temperature on the disordering reaction very precisely. It was found that disorder begins at existing antiphase domain boundaries but that at a slightly higher temperature (1°C) it also occurs by homogeneous nucleation within the domains. A small (∼ .01°C) further increase in temperature caused these micro-domains to completely fill the specimen.

The effect of temperature on high-resolution TEM image contrast

1995 ◽  
Vol 53 ◽  
pp. 640-641
Author(s):  
T. Geipel ◽  
W. Mader ◽  
P. Pirouz
Keyword(s):  
Form Factor ◽  
Inelastic Scattering ◽  
Accurate Method ◽  
Waller Factor ◽  
Effect Of Temperature ◽  
Specimen Thickness ◽  
Influence Of Temperature ◽  
Debye Waller Factor ◽  
Influence Of Temperature On ◽  
Atomic Form Factor

Temperature affects both elastic and inelastic scattering of electrons in a crystal. The Debye-Waller factor, B, describes the influence of temperature on the elastic scattering of electrons, whereas the imaginary part of the (complex) atomic form factor, fc = fr + ifi, describes the influence of temperature on the inelastic scattering of electrons (i.e. absorption). In HRTEM simulations, two possible ways to include absorption are: (i) an approximate method in which absorption is described by a phenomenological constant, μ, i.e. fi; - μfr, with the real part of the atomic form factor, fr, obtained from Hartree-Fock calculations, (ii) a more accurate method in which the absorptive components, fi of the atomic form factor are explicitly calculated. In this contribution, the inclusion of both the Debye-Waller factor and absorption on HRTEM images of a (Oll)-oriented GaAs crystal are presented (using the EMS software.Fig. 1 shows the the amplitudes and phases of the dominant 111 beams as a function of the specimen thickness, t, for the cases when μ = 0 (i.e. no absorption, solid line) and μ = 0.1 (with absorption, dashed line).

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