Michigan

Szymanski, Antonia

doi:10.4135/9781452276151.n251

Cited by 3 publications

(5 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The stability of the monomer forms' films is also increased by the presence of associated forms caused by an increased in the substance's concentration. This process is similar to the one in which Triton X-100 increases the stability of films of oxyethylated aliphatic alcohols; in the same way [lo] the associated forms behave like individual species [21].…”

mentioning

confidence: 63%

“…5, curve a). At 10 mg L-' the peak is also well-shaped, but its potential is 1.66 V. The peak for the associated forms probably prevails at this concentration [21]. The film obtained at this concentration is relatively stable, although a decrease in the peak height is observed for the second peak; all the following ones maintain a constant height (Fig.…”

mentioning

confidence: 80%

“…The adsorption of the Triton X series has been investigated using tensammetry with adsorptive preconcentration but without looking at the stability of the film [19-211. Oxyethylated isooctylphenols of the Triton X series with the following numbers of oxyethylene subunits were investigated within the concentration range 1-20 mg L-': 1 (X-15), 3 (X-35), 5 (X45), 8.5 (X-l14), 9.5 (X-loo), 12.5 (X-102), 30 (X-305), and 40 (X-405). The range of concentrations chosen according to literature data [21] allowed for the formation of adsorbed layers before and after the electrode was saturated with monomer or associated forms. Each form gives an individual peak on the tensammetric curve.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Stable layers of oxyethylated iso‐octylphenols adsorbed on the surface of a hanging mercury drop electrode under tensammetric conditions

Pawlak

1995

Electroanalysis

View full text Add to dashboard Cite

The stability of films of oxyethylated alkylphenols of the Triton X series on the hanging mercury drop electrode was investigated. The stability of the adsorbed layers increases upon increasing the concentration of the substance. More stable films were obtained after saturation of the electrode surface with monomeric forms. The stability of the film increases in the presence of associated forms.Keywords: Adsorptive stripping tensammetry, Nonionic surfactants, Oxyethylated alkylphenols, Stable layers Oxyethylated alkylphenols are widely used surfactants which can be present in surface waters due to their incomplete biodegradation. Ethoxylates adsorbed on the electrode surface can influence the electrode processes. They may cause a decrease in the height, a shift, or even complete disappearance of the voltammetric peaks and polarographic waves of depolarizers. This influence is useful in the technique called electrochemical masking, but it might be a source of error i n natural waters' analysis [ 1-91, Triton X-100 (ethoxylated iso-octylphenol) as well as ethoxylated alcohols form stable films on the surface of a hanging mercury drop electrode (HMDE) [I9-121. A film of Triton X-100 is a source of error in trace element analysis, even when medium exchange is used [9]. This stable film of Triton X-100 can only be disturbed by vigorously stirring the solution and simultaneously applying an electrode potential above the adsorption range of this surfactant [lo, 131. Poly(ethoxy1ated) compounds are used to modify the graphite electrode [14-161. Using polarography it was found that iso-ocbylphenols of the Triton X series (X-100, X-305, X-405) facilitate the transfer of some metal ions (by complexation) across aqueous/organic solution [17].Bearing in mind what was said above and checking the conditions under which stable films of ethoxylates, including oxyethylated isooctylphenols, are formed could be very important as they might be of use for possible future applications of these films. In the case of oxyethylated aliphatic alcohols and Triton X-100, a tensammetric method for investigating the stability of the film has been developed [lo]. According to this method, when a surfactant forms a film on the surface of the HMDE the tensammetric peaks can be repeatedly recorded after a single preconcentration period. Similar experiments were performed in order to distinguish "pure" tensammetric from faradaic processes in adsorptive stripping tensammetry (AdST) [18].The aim of the present communication is to examine the stability of layers of ethoxylated iso-octylphends of the Triton X series at an HMDE, based on repetition of the tensammetric peak at the same drop after a single preconcentration. The adsorption of the Triton X series has been investigated using tensammetry with adsorptive preconcentration but without looking at the stability of the film [19-211. Oxyethylated isooctylphenols of the Triton X series with the following numbers of oxyethylene subunits were investigated within the concentration range 1-20 ...

show abstract

mentioning

confidence: 63%

mentioning

confidence: 80%

mentioning

confidence: 99%

See 1 more Smart Citation

Stable layers of oxyethylated iso‐octylphenols adsorbed on the surface of a hanging mercury drop electrode under tensammetric conditions

Pawlak

1995

Electroanalysis

View full text Add to dashboard Cite

show abstract

“…Such an approach has been attempted to explain the similarity of the 0 (25 in super-deformed bands, see for example [34,35]. One may try to understand the close values of 0 (2) as the result of a cancellation between various quantities that influence the moment of inertia.…”

Section: Identical Bandsmentioning

confidence: 99%

Interaction strength and shape difference for the h9/2 and h11/2 configurations in163Tm

Jensen

Hagemann

Tjøm

et al. 1991

Z. Physik A - Hadrons and Nuclei

View full text Add to dashboard Cite

The strongly shape driving ~h9/21541]1/2 configuration with a = + 1/2 exhibits some anomalous, and so far unexplained, features concerning the crossing frequency, ho~c, the aligned angular momentum, ix, and interaction strength, at the alignment of the first pair of i13/2 quasineutrons in several odd-Z rare earth-nuclei. The h9/2154111/2and hlU 2152317/2bands have been studied in the stably deformed rare-earth nucleus 163Tm to investigate these features. A difference in band crossing frequency of ~ 80 keV between the two bands is found. Rotational bands built on these two configurations have been found to cross in the spin range I= 25/2-29/2 h. The y-decay pattern between the two bands is established in the crossing region and analysed in terms of a moderate shape difference between them. A theoretical estimate of the size of the interaction strength between the two bands is presented and compared to the experimental value. The observed band structure in 163Tm is very similar to that of 167Lu which has 2 protons and 2 neutrons in addition.This observation is discussed in relation to the similarity of the yrast bands of the two even-even "core" nuclei 16aEr and 166yb, for which the y-transition energies are identical within ~0.2 keV below the vi13/2 crossing.

show abstract

“…The advantage of such an approach is lack of foaming during gas-bubbling and lack of an ethyl acetate loss during this stage. When DPrecording is applied [15], in order to avoid an oxygen peak appearance, sodium sulfite is used as a base electrolyte. The ITT, used together with a simple liquid-liquid extraction scheme or with the precipitation of NS by a bismuth(lII) iodide complex (the BiAS separation scheme) is very useful in the analysis of NS in different environmental samples [16 ± 18].…”

Section: Introductionmentioning

confidence: 99%

The Adsorptive Stripping Indirect Tensammetric Technique

Szymański¹,

Łukaszewski²

2002

Electroanalysis

View full text Add to dashboard Cite

A new tensammetric technique for the determination of trace concentrations of non‐ionic surfactants (NS) has been developed. The adsorptive stripping indirect tensammetric technique (AdS‐ITT) combines an adsorptive preconcentration of a substance‐to‐be‐determined with the indirect tensammetric technique (ITT). The lowering of the tensammetric peak of the monitoring substance – ethyl acetate, is the analytical signal in the AdST‐ITT, as it is in the ITT. The dynamic response range can be shifted towards a lower concentration range by one to three orders of magnitude by the selection of an adequate preconcentration time. However, the dispersion of calibration plots of different NS is larger in the AdS‐ITT than in the ITT. The detection limit (at 60 seconds of preconcentration) is approximately 0.1 μg in the sample, i.e., more than one order of magnitude better than that without preconcentration. The ‘zero signal' of ethyl acetate is considerably lower in the AdS‐ITT than in the ITT due to adsorption of impurities of the base electrolyte.

show abstract

Michigan

Cited by 3 publications

References 0 publications

Stable layers of oxyethylated iso‐octylphenols adsorbed on the surface of a hanging mercury drop electrode under tensammetric conditions

Stable layers of oxyethylated iso‐octylphenols adsorbed on the surface of a hanging mercury drop electrode under tensammetric conditions

Interaction strength and shape difference for the h9/2 and h11/2 configurations in163Tm

The Adsorptive Stripping Indirect Tensammetric Technique

Contact Info

Product

Resources

About