And potentiometric measurements

Rubio R, Sanz J, Rauret G. 1987. Determination of cyanide using a microdiffusion technique and potentiometric measurement. Analyst 112 1705-1708. 

Uses, aminothiazoles derivatives, 132-172 hydroxythiazole derivatives, 438-442 mercaptothiazole derivatives, 438-442 UV spectra, 21 of alkylaminothiazoles. 38 and amino-imino equilibrium, 19, 20 and charge transfer, 21 of iminothiazolines, 38 and PPP calculations, 21 and potentiometric measurements, 21 representative data, 22 of Schiff bases, 41 and solvent effects, 21 and substituent effects, 22 of sulfathiazoles, 20 -of sulfonamidothiazoles, 116 of A-2-thiazoline-4-one, 422 pKa determination, 423 of A-4-thiazoline-2-one, in relation with protomerism, 387 representative data, 389 of A-4-thiazoline-2-thiones, 380. 381 in relation with protomerism. 378 of thiazolylcarbamates, 97 of thiazolyl-2-oxides, 409 of thiazolyl-4-oxides, 426 of 2-thiazolylthioethers, 404 of thiazolylthioureas, 94, 96 of thiazolylureas, 93... 

However, the view that hydrophobic forces are responsible for the compact structure characteristic of unneutralized PMA, which was also held by Russian workers 15), has recently been criticized by Mandel et al. 9). These authors draw on spectroscopic and potentiometric measurements carried out on a conventional PMA sample in water and in water-methanol (40%) mixtures. 

In the Ektachem 700 the electrolytes (sodium, potassium, chloride, carbon-dioxide) are measured potentiometrically. The slides to be measured are transported by the instrument via the slide rotor to the preparatory position from where the slides are immediately pushed into the incubator. In the incubator the temperature of the slides is maintained at 25.0 0.5°C. The evaporation is minimised since each slide is covered up. A total of 17 slides can be accommodated in the incubator. The total incubation time is 3 minutes. After incubation has been completed, the slide is transported to the measurement position in the electrometer and potentiometric measurement can now be performed. The result is transmitted to the computer and the measured slide can be ejected to waste. 

Lubal and Havel studied the complex formation between UOj photometric and potentiometric measurements at (298.2 0.5) K. The spectrophotomet-ric measurements were carried out in 3 M Na(CI04, SeO ) medium. The total selenate concentration was varied between 0 and 0.6 M and the concentration was kept... 

Gas phase composition and the oxidation state of the catalyst, represented by its oxygen activity, during selective oxidation of acrolein over an oxidic multicomponent catalyst were both monitored by simultaneous kinetic and potentiometric measurements. 

We can expect that the eombination of the kinetic and potentiometric measurements will give a strong hint concerning the role of the different phases within the reaction network and may lead to practical correlations between the oxidation state of a catalyst and its kinetic behaviour (selectivity and activity) during oxidation. 

On the basis of the observed results there is no question that the fundamental interpretation of the left-hand side of Equation 1 is expressed correctly in Equation 19. The discrepancy between our results and those of Merle has to be a consequence of the greater accuracy of the ge volume and potentiometric measurements performed in this research. Merle did not correct for the volume of solution contained between gel beads nor did he calibrate his glass electrode in the presence of the fully dissociated sodium polyvinyl sulfate medium that he used. 

Recently a convenient and precise method has been devised for the determination of thermodynamic data for copper (I)-olefin complexes 67> based on the coulometric generation of Cu(I) and potentiometric measurement of the Cu(I) activity in a lithium perchlorate-2-propanol medium. The formation constants for the reaction Cu(I) (2-propanol) + olefin (2-propanol) Cu(I) olefin (2-propanol), were found to be linearly related to those of the corresponding... 

Clark et al. [32] have published in 1981 a method employing both enzymes in solution and potentiometrically measuring the concentration of the hydrogen peroxide formed. For an amperometric cholesterol assay Yao et al. [33, 34] used immobilized cholesterol esterase and cholesterol oxidase in a reactor assaying the hydrogen peroxide formed at a peroxidase electrode with the redox pair hexacyanoferrate(II)/hexacyanoferrate(III) as a mediator. 

An excess of boiling trifluoroacetic anhydride reacts with sodium arsenite to give the compound NaAs0(CF3C02)2 in good yield, and similar bismuth reactions also take place. Polarographic and potentiometric measurements in aqueous solution point to the formation of a complex [As(OH)2HX]" between arsenic(iii) and nitrilotriacetic acid (HaX). ... 

By spectrophotometric and potentiometric measurements in AlCls-NaCl melts, Bjerrum [409] found the following ions and species S(IV), S(II), 82, ... 

Table 57. Relative Q -Acceptor Strength of Chloride Ion-Acceptor Chlorides towards Covalent (C6H5)3C1 and Polar (C2H5)4NC1 Chlorides as Found by Spectrophotometric and Potentiometric Measurements in Phenylphosphonic Bichloride...

Because the electrode process takes place solely at the surface of the working electrode, amperometric flow cells can determine only local (interfacial) concentrations. Conductometric and potentiometric measuring cells, on the other hand, can track the average volumetric concentrations in the eluate. The same holds for UV detection, which is preferred for routine HPLC studies (see Section 12.2.6.3). 

In the last decade increasing attention has been paid to the electeochemical studies on the kinetics and equilibrium of ion transfer at the oil/water interfaces that are polarized in the sense that the interface is of the ideal-polarized nature for all ions (here Bi, Ai, B2, and A2) except transferring ion or ions (here B3) (for reviews see [31-38].) In such cases the nontransferable ions serve as the supporting electrolytes for the transport process of the transferable ions across the interface. It has been shown that the oil/water interface works as an ion-selective electrode surface for both vol-tammetric (and amperometric) and potentiometric measurements of ions, both based on the same electrochemical principle of ion transfer across the interface [43,44]. There it is essential that the oil/water interface is of the ideal-polarized nature for all ions (such as counter ion and supporting electrolyte ion so-called potential window) except the monitored ion or ions (voltammetry). 

The multitransduction of signals was explored for the quantification of metals in solution. A polymeric membrane sensor was developed by incorporation of 5,10,15,20-tetra(ferrocenyl)porphyrin [248]. Simultaneous optical and potentiometric measurements made possible the detection of lead in the 2.7 x 10 to... 

Alkali-metal halides are textbook examples of strong electrolytes. However, conductance and potentiometric measurements reveal that there are some salts which behave differently and do form ion pairs by the strong attraction of the unlike ions. For these systems, a chemical model of ion pairing as proposed in Refs. 17 to 20 can be applied to consider the equilibrium between the completely dissociated electrolyte and the ion pair... 

The useful joint application of accurate microcalorimetric and potentiometric measurements is illustrated by all cases mentioned above. 

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