ISEC

Exhibition duting International Solvent Extraction Conference ISEC 1974, Lyon, France, 1974. 

G. H. Beyer, Proceedings of the International Solvent Extraction Conference ISEC 1977, The Canadian Institute of Mining and Metallurgy, Ottawa, Canada,... 

Mendes-Tatsis, M.A., Agble, D., Mass transfer with interfacial convection and added surfactants, Int. Solvent Extraction Conf (ISEC 96) Value adding through solvent extraction, Ed. Shallcross, D.C., Paimin, R. Prvcic, L.M., Melbourne, Australia, pp.267-272, 1996. 

ISEC is a size-exclusion chromatography technique, in which the stationary phase is the CFP to be to characterized [16-18] and the eluates are geometrically well-defined steric probes. From the determined retention volumes in a given solvent and on the basis of suitable morphological models, ISEC analysis provides the... 

PGSE-NMR provides direct information on the translational mobility of a liquid medium capable of swelling a given CFP. The self-diffusion coefficient of the swelling agent is found to be related to the nanoporosity of the matrix as determined from ISEC and to the rotational correlation time of a suitable paramagnetic probe (ESR) [22]. 

Synthesis (TCS). The very same term was independently proporsed by Corain and associates for the size controlled synthesis of palladium nanoparticles in 2004 [68]. In a number of cases they observed that palladium nanoclusters, supported on gel-type resins of different nature and obtained with the RIMP method, exhibited a remarkable agreement between the size of the cavities of swollen supports (as assessed by means of ISEC, see Section 4) and the diameter of the metal nanoclusters (Table 4, Entries 1-3) [10,11,66,71,72,87]. 

Figure 10. Pore volume distribution of the support as assessed with ISEC (a) and the metal nanoclusters size distribution as assessed with TEM (b) for a Pd /CFP catalyst. (Reprinted from Ref. [68], 2004 with permission from Wiley.)...

The model, therefore, predicts the elution behavior of solutes during a chromatographic process over a swollen gel as the stationary phase as a function of solute size and of the gel nanomorphology. On the reverse, from the elution behavior of solutes of known molecular size it is possible to extract the polymer chain concentration from chromatographic experiments, where an unknown swollen gel is the stationary phase. This is the basis of the ISEC, which is so often mentioned through this chapter [16,17,105,106]. 

Measured in water (ISEC characterization based on the Ogston s model assumption is not generally reliable in alcohols owing to the occurrence of enthalpic interactions [151]). 

Table 1. ISEC characterization of the cross-linked functional polymer MPIF Na". ...

A second project [10] was based on the production of Pd nanocluster inside poly-methacrylic acid (8%mol)-A,iV-di-methylacrylamide (88 % mol)-A, A -methylenebisacrylamide (4% mol). ISEC (Inverse Size Exclusion Chromatography) analysis of the resin in water in terms of cylindrical pores [7]... 

In this case we took care of a very major question concerning the reliability of the metal nanocluster diameters determination to be compared with the ISEC-based nanostructural outcomes of the macromolecular mold. In fact TEM analysis is based on the counting of some hundreds of metal nanoclusters and the pretence to propose such universal criterion as TCS had to cope with a far more reliable verification. 

We choose resin DOMA-VP (4-vinylpyridine (4% mol)-dodecyknethacrylate (92% mol)-ethyleneglycoledimethacry-late (4% mol)). Figure 4, support for testing the intuition. A Pd /DOMA-VP nanocomposite was produced in THE and ISEC analysis in THE (Table 2) gave the pattern illustrated in Figure 5. 

TEM analysis provides results extremely compatible with ISEC analysis (Figure 6). 

Figure 5. Nanoporosity of DOMA-VP as determined with ISEC. (Reprinted from Ref [5], 2004, with permission from Wiley-VCH.)...

Very recent relevant observations reveal that the TCS approach albeit certainly significant as conceptual and operational tool in the issue of metal nanoclusters size control, requires a substantial further perfection. Resin sulfonated Bayer K1221 is a co styrene-divinylbenzene commercially available gel-type resin, in beaded form. Its cross-linking degree is ca. 4% mol and therefore K1221 is expectedly quite similar to DOMA-VP and MTEMA-DMAA 4-4 for example. In fact ISEC analysis reveals a nanoporosity featured by 4.0 and 2.0 nm nanopores only. The expectation is that a Pd°/K1221 nanocomposite obtained with a classic procedure [5,9,10] will exhibit diameters strictly ranging from 2 to 4 nm. 

Table 8. ISEC characterization of the macromolecular template MTEMA DMAA 4-8.

The extremely good agreement between M° nanoclusters size production and the ISEC-based prediction is illustrated in Table 9. 

ISEC 71, Proceedings of International Conference on Solvent Extraction, The Hague, April 1971, Sodety of Chemical Industry, 1971. 

Also, SEC-cSFC has been reported [947]. Due to the nature of the interface and the use of conventional-sized SEC columns, only small portions of the SEC fractions can be analysed by cSFC (i.d. <100 xm) packedcapillary SFC would be an obvious improvement to avoid overloading. Fujimoto el al. [931] have reported the combined power of [iSEC-TLC-DRIFT (in situ). Because of the reduced flow-rate, microcolumn HPLC has great promise for this type of coupling. 

Value Adding through Solvent Extraction, [Papers presented at ISEC 96], Melbourne, Mar. 19-23, 1996, 1, 517-522. 

Feather, A. M. Cole, P. M. The separation of cobalt from nickel ammonium sulfate solution by solvent extraction. Value Adding through Solvent Extraction, [Papers presented at ISEC 96], Melbourne, Mar. 19-23, 1996, 1, 511-516. 

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