High-speed computers as a supplement to graphical methods—V1Haltafall, a general program for calculating the composition of equilibrium mixtures

Ingri, Nils; Kakolowicz, Wladysław; Sillén, Lars Gunnar; Warnqvist, Björn

doi:10.1016/0039-9140(67)80203-0

Cited by 433 publications

(117 citation statements)

References 17 publications

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“…Comparison of the anions and cations that we have estimated to be in the cell wall space gives ratios for ca1cium:magnesium:organic acid:unesterified uronic acid, on the basis of charge, of 15:4:0:28 for the unripe fruit and figures the relative proportions of the different ionic species were calculated using a computer program designed to predict equilibria in complex mixtures (Ingri et al, 1967).…”

Section: Discussionmentioning

confidence: 99%

The Use of Nonaqueous Fractionation to Assess the Ionic Composition of the Apoplast during Fruit Ripening

1995

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We have examined the possibility that pectin solubilization and cell separation in fruit may be due to organic acids disrupting calcium bridges between pectic polysaccharides. With fruit from a wild tomato (Lycopersicon pimpinellifolium [Dunall) we demonstrated the validity of a nonaqueous fractionation method to obtain reliable estimates of the ionic content of the apoplast. I n unripe fruit no organic acids were associated with the cell wall, which contained 67% of the total calcium and 47% of the magnesium. I n ripe fruit 4% of the malate, 10% of the citrate, and 15% of the oxalate were estimated to be in the cell wall, together with 84% of the calcium and 52% of the magnesium. In contrast to the cultivated tomato, we did not find a consistent decrease i n the degree of methyl esterification between unripe and ripe fruit, and an overall average of 75% was observed. I n the cell walls of ripe fruit the ratio of ca1cium:magnesium:organic acid:unesterified uronic acid, on the basis of charge, was 15:4:4:16. The use of a computer program to predict the proportions of different ionic species in complex mixtures suggested that in ripe fruit 70% of the unesterified uronic acid would be complexed with calcium. Our results show that organic acids do not accumulate in the cell wall sufficiently to disrupt calcium cross-linking, nor is the calcium removed from the wall into the cell. We therefore conclude that organic acids do not contribute to cell separation during the ripening of tomato fruit.

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Section: Discussionmentioning

confidence: 99%

The Use of Nonaqueous Fractionation to Assess the Ionic Composition of the Apoplast during Fruit Ripening

1995

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“…The standard deviations were defined and calculated according to Sill~n [13,14]. For simulating the equilibrium concentrations of the systems for given sets of stability constants use was made of the program HALTAFALL [15]. Computation was performed on a DEC 10-70 computer.…”

Section: Methodsmentioning

confidence: 99%

“…cit.) these were used for refinements with LETAGROP[ll, 12,14] and HALTAFALL [15] computations. Their values, given in Table 4, were determined at an ionic strength of 0.5 M (KNO3).…”

Section: Stability Constantsmentioning

confidence: 99%

The oxalato complexes of titanium(IV)—I

Velde

1977

Journal of Inorganic and Nuclear Chemistry

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Abstract--Molecular weight, electrodialysis and anion exchange measurements between pH 1 and 4 showed that the titanyl oxalate anion is present in solution as mononuclear Ti(OH)2(C204)22 units, pH studies of solutions of (NI-L)2TiO(C204)2.H20 in 0.5 M NaCIO4 medium and computer evaluation and simulation by LETAGROP and HALTAFALL showed that the behaviour of such solutions can be simulated by applying stability constants of log/31 = 7.90 +-0.02 and log/32 = 13.24 +-0.07, when using hydrolysis constants given by Nazarenko et al.In an attempt to determine the stability constant/32 spectrophotometrically using an exchange method with pyrocatechol, a mixed ligand complex was found with a Ti:pyrocatechol:oxalate ratio of 1:1:1.

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“…The data (200 points, drift Ͻ 1 mV/min) were mathematically treated by use of the program SUPERQUAD [27] with a Marquardt algorithm while the distribution of species was calculated with the program Haltafall. [28] Calibration of the pH meter and the electrode system was performed prior to each measurement with a standardized HCl solution (µ ϭ 0.1 , KCl) at 20.0°C: 10 mL of the latter were titrated with a standardized 0.1  KOH solution at a ionic strength of 0.1, and the electrode potential readings were converted to pH. The ion product of solvent (pK w ϭ 13.91) and electrode potential were refined by use of the program Scientist Ϫ5  at pH 0 ഠ 2 by KOH (0.050 ⁾.…”

Section: Syntheses (See Scheme 1) Methyl 2-(bromomethyl)benzoate (1)mentioning

confidence: 99%

Lanthanide Chelates Based on Diethylenetriamine Fitted with O‐Benzoic Acid Pendant Arms

Fatin‐Rouge

Bünzli

2003

Eur J Inorg Chem

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A new polycarboxylate ligand H 5 L has been synthesized by the attachment of five benzoate subunits onto a diethylenetriamine framework. Seven pK a values have been determined by potentiometry, spectrophotometry and NMR spectroscopy as 1.9(2), 2.8(2), 3.87(5), 4.58(6), 4.87(6), 9.19(6) and 11.68(5), the first four corresponding to the carboxylic functions and the last three to amine sites. The interaction between H 5 L and Ln III ions in dilute aqueous solution has been examined by UV/Vis absorption and emission spectrometries, and has been found to result in monometallic complexes that are moderately stable in the pH range 3.7−7.5. Conditional stability constants at pH 5.3 are logK 11 = 5.3(2), 6.6(1), 6.5 (1)

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High-speed computers as a supplement to graphical methods—V1Haltafall, a general program for calculating the composition of equilibrium mixtures

Cited by 433 publications

References 17 publications

The Use of Nonaqueous Fractionation to Assess the Ionic Composition of the Apoplast during Fruit Ripening

The Use of Nonaqueous Fractionation to Assess the Ionic Composition of the Apoplast during Fruit Ripening

The oxalato complexes of titanium(IV)—I

Lanthanide Chelates Based on Diethylenetriamine Fitted with O‐Benzoic Acid Pendant Arms

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