scholarly journals Desing of optical chemosensors for detection of cyanide ions in water environments

2019 ◽  
Vol 15 (1) ◽  
pp. 82-87
Author(s):  
Alexandra Alexandrovna Kudrevatykh ◽  
Lyubov Stepanovna Klimenko ◽  
Timofey Petrovich Martyanov
Keyword(s):  
Aqueous Medium ◽  
Absorption Spectra ◽  
Stability Constants ◽  
Molecular Interactions ◽  
Color Change ◽  
Cyanide Ion ◽  
Colorimetric Test ◽  
Optical Chemosensors ◽  
Aqueous Mixture ◽  
The Stability

Molecular interactions with various anions in the form of tetrabutylammonium salts in DMSO and DMSO-aqueous mixture were studied spectrophotometrically. It turned out that the solutions of 1-hydroxy-2-acylaminoanthraquinones in DMSO, originally yellow, became dark purple with the addition of cyanide, fluoride, phosphate, and acetate ions. The addition of other salts did not cause changes in the absorption spectra. When switching to aqueous DMSO, a contrasting color change in the solution was observed only with the addition of the cyanide ion. The stability constants of the complexes and the metrological characteristics of the processes were determined. On the basis of 1hydroxy-2-benzoylaminoanthraquinone, colorimetric test strips were made and tested for the detection of CN-ions in an aqueous medium.

Physicochemical investigation on thiomalate complexes of nickel

1968 ◽  
Vol 21 (3) ◽  
pp. 641 ◽  
Author(s):  
RS Saxena ◽  
KC Gupta ◽  
ML Mittal
Keyword(s):  
Aqueous Medium ◽  
Stability Constants ◽  
Alternative Methods ◽  
Acid System ◽  
Kcal Mole ◽  
Physicochemical Investigation ◽  
Different Temperatures ◽  
The Stability ◽  
Ph Range ◽  
Deep Violet

Potentiometric and conductometric studies of the nickel-thiomalic acid system, in aqueous medium of 0. lM KNO3, reveal the formation of two complexes; one light violet 1 : 1 predominating at pH 6.5-7.5 and another deep violet 1 : 2 in the pH range 8.5-10.0. The stability constants of the complexes formed have been determined by applying Calvin and Melchior's extension of Bjerrum's method at three different temperatures and were further refined by using alternative methods. The logK values (final) for 1 : 1 and 1 : 2 complexes at 20, 25, and 30� have been found to be 7.86, 7.87, 7.96, and 6.24, 6.31, 6.39 respectively. The values of the overall changes in ΔG, ΔH, and ΔS accompanying the reaction have also been evaluated at 25� and found to be -19.31 kcal/mole, -8.77 kcal/mole, and +35.36 cal/deg respectively.

Interligand interaction in ternary complexes of Zn(II) and Cd(II) with dipeptides and aminoacids

1994 ◽  
Vol 72 (4) ◽  
pp. 1107-1110 ◽  
Author(s):  
Alexander Varghese Vaidyan ◽  
Pabitra K. Bhattacharya
Keyword(s):  
Ionic Strength ◽  
Aqueous Medium ◽  
Computer System ◽  
Stability Constants ◽  
Ternary Complexes ◽  
Binary And Ternary Complexes ◽  
The Stability ◽  
Interligand Interaction

The stability constants of binary and ternary complexes [MA], [Ma2], and [MAL] (where M = Zn(II) or Cd(II); A = glycylglycine, glycyl L-alanine, glycyl L-leucine; L = α-alanine phenylalanine, tyrosine, tryptophan, or L-histidine) in aqueous medium have been determined potentometrically at 25 °C and an ionic strength of 0.2 M NaClO4 (0.2 mol dm−3) using a computer system. It is observed that Δ log K of MAL complexes has low negative or positive values. Probable reasons have been discussed.

Study of some properties of dithiocarbamates derived from heterocyclic amines

1980 ◽  
Vol 45 (3) ◽  
pp. 800-809 ◽  
Author(s):  
Štefan Kúdela ◽  
Ján Garaj ◽  
Helena Hofbauerová ◽  
Viktor Kettmann
Keyword(s):  
Physicochemical Properties ◽  
Absorption Spectra ◽  
Stability Constants ◽  
Spectrophotometric Determination ◽  
Heterocyclic Amines ◽  
Ir Absorption ◽  
Coulometric Determination ◽  
Ir Absorption Spectra ◽  
The Stability

Some physicochemical properties of sodium pentamethylenedithiocarbamate and complexes with Cu(II), Ni(II), and Fe(III) were studied. The bands in the electronic and IR absorption spectra were measured and characterized, and the possibility of coulometric determination of NaS2CN(CH2)5.2 H2O was examined. The conditions for spectrophotometric determination of trace quantities of Cu(II), Ni(II), and Fe(III) as dithiocarbamate complexes were established and the stability constants of the complexes were determined.

Study of the Coordinated System Cd(II)-Valine-Valinate Ion

1992 ◽  
Vol 57 (9) ◽  
pp. 1811-1820
Author(s):  
Jesús César Rodríguez Placeres ◽  
Ana María Alloza Moreno ◽  
Remedios Sosa Diaz ◽  
Graciliano Manuel Ruiz Cabrera
Keyword(s):  
Aqueous Medium ◽  
Stability Constants ◽  
Polarographic Method ◽  
The Stability

The polarographic method has been applied to the study of the coordinated systems Cd(II)-neutral valine and Cd(II)-valinate ion in aqueous medium and I = 1.0 mol l-1 (NaClO4). The stability constants of the complexes were determined as: [Cd(HV)]2+ (β10 = 7 ± 0.5), [Cd(HV)2]2+ (β20 = 24 ± 4), [Cd(HV)3]2+ [β30 = (1.5 ± 0.32) . 102], [Cd(V-)]+ [β01 = (4.1 ± 0.3) . 103], [Cd(V-)2] [β02 = (1.3 ± 0.2) . 107], [Cd(V-)3]- [β03 = (1.5 ± 0.3) . 109], [Cd(HV)(V-)]+ [β11 = (4.3 ± 0.8) . 104], [Cd(HV)(V-)2] [β12 = (1.7 ± 0.3) . 107] and [Cd(HV)2(V-)]+ [β21 = (1.2 ± 0.3) . 105].

scholarly journals Synthesis ,spectroscopic study of Antipyryl azo 2-Naphthol and use it as new reagent for determination of Co(II) and Cu(II)

2013 ◽  
Vol 10 (3) ◽  
pp. 977-985
Author(s):  
Baghdad Science Journal
Keyword(s):  
Optimum Condition ◽  
Spectroscopic Study ◽  
Aqueous Medium ◽  
Stability Constants ◽  
Spectrophotometric Method ◽  
Full Color ◽  
Color Development ◽  
The Stability ◽  
Sensitive Spectrophotometric Method

A simple ,accurate and sensitive spectrophotometric method has been developed the determination of Cobalt(II) and Cupper (II) .The method is based on the chelation of Co(II) and Cu(II) ions with 4-(4´-pyrazolon azo) -2-Naphthol(APAN) in aqueous medium . The complexes have a maximum absorption at (513) and (506) nm and ? max 0.531×10 4 and 0.12×10 5 L.mol -1.cm -1 for Co(II) and Cu(II) respectively .The reagent and two complexes have been prepared in ethanolic solution.The stoichiometry of both complexes were found to be 1:2 (metal :legend) .The effects of various cations and anions on Co(II) and Cu(II) determination have been investigated .The stability constants and standard deviations for Co(II) and Cu(II) 0.291 x107 ,0.909X108 L.mol -1 ,(0.291) and (0.332) respectively .The optimum condition for full color development for described methods were applied satisfactorily to synthetic samples.

Extraction of strontium and barium salts by the nitrobenzene solution of dicarbolide in the presence of glymes

1985 ◽  
Vol 50 (3) ◽  
pp. 581-599 ◽  
Author(s):  
Petr Vaňura ◽  
Emanuel Makrlík
Keyword(s):  
Stability Constants ◽  
Organic Phase ◽  
Equilibrium Constants ◽  
Minor Role ◽  
Nitrobenzene Solution ◽  
Ligand Structure ◽  
Stability Constants Of Complexes ◽  
Separation Factors ◽  
The Stability ◽  
A Minor

Extraction of microamounts of Sr2+ and Ba2+ (henceforth M2+) from the aqueous solutions of perchloric acid (0.0125-1.02 mol/l) by means of the nitrobenzene solutions of dicarbolide (0.004-0.05 mol/l of H+{Co(C2B9H11)2}-) was studied in the presence of monoglyme (only Ba2+), diglyme, triglyme, and tetraglyme (CH3O-(CH2-CH2O)nCH3, where n = 1, 2, 3, 4). The distribution of glyme betweeen the aqueous and organic phases, the extraction of the protonized glyme molecule HL+ together with the extraction of M2+ ion and of the glyme complex with the M2+ ion, i.e., ML2+ (where L is the molecule of glyme), were found to be the dominating reactions in the systems under study. In the systems with tri- and tetraglymes the extraction of H+ and M2+ ions solvated with two glyme molecules, i.e., the formation of HL2+ and ML22+ species, can probably play a minor role. The values of the respective equilibrium constants, of the stability constants of complexes formed in the organic phase, and the theoretical separation factors αBa/Sr were determined. The effect of the ligand structure on the values of extraction and stability constants in the organic phase is discussed.

Studies on the Coordination Reaction of VO2+ and Tannic Acid in the Tannin Extract Desulfurization

2012 ◽  
Vol 239-240 ◽  
pp. 1573-1576
Author(s):  
Zhu Qing Gao ◽  
Xiao Dong Cai ◽  
Kai Cheng Ling
Keyword(s):  
Stability Constants ◽  
Tannic Acid ◽  
Ph Value ◽  
Protonation Constants ◽  
Conditional Stability ◽  
Tannin Extract ◽  
Acid Effect ◽  
Different Temperatures ◽  
The Stability ◽  
Apparent Stability

At different temperatures, the protonation constants of tannic acid and the complex apparent stability constants between tannic acid and VO2+ were determined by using pH potentimetric method. The results showed that the protonation constants and the complex apparent stability constants slightly decreased with the raising temperature. In accordance with the pH value in the tannin extract technology, the conditional stability constants of the complex were calculated on the basis of the acid effect of tannic acid and the hydrolysis effect of VO2+. It was found that pH greatly affected the stability constants of the complex , so pH must be strictly controlled in the tannin extract technology.

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