Anchor technique

In summary, the Kobayashi solution to the development of a SILP for catalytic applications in liquid biphasic conditions implies the adoption of a more robust anchoring technique of the catalytically active species to the solid support and of a IL/solvent pair as far as possible in terms of mutual solubility, namely water and [dbim][SbF6]. The role of the IL impregnated on the solid support is that of creating a hydrophobic environment on the surface of the silica material where the catalyst, ionically bound to the organic spacer, exerts its role promoting the desired reaction. Since the catalyst is easily separated from water, the system could be easily optimised for recycle. 

Supported metallocene catalysts are an important field of research for the polymer industry and shall be mentioned here only briefly. Single-site olefin polymerization catalysts have been extensively investigated and are now achieving wide acceptance in the polyolefin industry. In order to achieve commercial significance, these soluble metallocene catalysts have to be immobilized on a carrier. The challenges of supporting these catalysts have been addressed in many creative ways and this topic has been taken up in an excellent review by Carnahan et al. [87]. This paper mainly describes anchoring techniques to silica, but these concepts may also be applied for other purposes. 

Courtois, J., Szumski, M., Bystroem, E., Iwasiewicz, A., Shchukarev, A., and hgum, K., A study of surface modification and anchoring techniques used in the preparation of monohthic microcolumns in fused silica capillaries, J. Sep. Sci., 29, 14, 2006. 

Fig.3.5. The anchor technique. This technique is very valuable for providing safe and distal occlusion when there is a question about instability of pushable fibered coils. Diagrammatically, the guide catheter is placed in the artery to be occluded and a 5-F inner catheter or microcatheter is advanced into a side branch next to the site requiring occlusion. At least 2 cm of a 14-cm standard Nester or Micronester are advanced into the side branch which is normally sacrificed. The rest of the coil is then deployed just proximal to that side branch and additional coils are packed so that cross-sectional occlusion is obtained...

Fig. 17.10. Anchor technique. The first centimeters of a long coil are carefully placed in a side branch immediatelyproximal to the site to be occluded. This technique prevents coil migration at the time of placing additional coils to obtain complete cross-sectional occlusion...

PAVM with normal flow PAVM with high flow Scaffold technique Anchor technique Anchor technique Vein of Galen technique... 

PAVM with large feeding artery Anchor technique Occlusion halloon-assisted technique... 

Fig. 9.4. In a large heated tent a composite liner was constmcted in the miHHle of winter. Anchoring technique (Riegelbauweise) can ensure a complete intimate contact between geomembrane and mineral layer even under these conditions (Sect 9.3.2) (Krath and Schwarz 1993 Schicketanz 1995). Courtesy Schicketanz Consulting Engineers, Aachen...

The anchoring technique will be explained by describing a typical installation day using the example of a composite liner construction, though the span of events within an installation day can change quite broadly. This will then be a somewhat simplified and idealized representation, but all key aspects will be clearly explained. Fig. 9.8a and b schematically shows the different installation phases, which comprise the anchoring technique. 

Fig. 9.12b. This photograph shows that the anchoring technique provides complete flatness even in critical areas (slope toe and pipe penetration constractions). In such places where hand-welded extrusion fillet seams occur in higher frequency and standing leachate can be expected, special care and high technical installation skills are required. Only experienced, particularly qualified and well-equipped specialist installation companies can master this task. Courtesy Schicketanz Consulting Engineers, Aachen...

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