Grafting procedures

In the absence of dyes, APA- and AdPA-grafted silica bind La(III) with, respectively, 0.20 and 0.27 mmol/g sorption capacity, resulting in formation of 1 2 (La L) complexes. 50% of introduced cation is bonded at pH=5 (APA), pH=6.1 (AdPA) and complete adsorption occurs at pH=6 (APA), pH=6.5 (AdPA). The grafted support in absence of La adsorbs the chosen dyes at pH<4 due to the electrostatic interaction with the -NH, groups on the surface, present as a result of grafting procedure. The adsorption of dyes at pH>4 is insignificant. 

The grafting procedure is straightforward, which is a major advantage of this method. The silica was pretreated to remove water from the support, after which it was added to a dichloromethane solution containing the catalyst. After 6 hours of mixing the supported catalyst was isolated by filtration. The remaining solvent was colourless... 

Transplantation entails the transfer of living cells/tissue/organs from a donor to a recipient. In some cases (e.g. many skin grafting procedures) the donor and recipient are actually the same individual, and this is termed autologous transplantation. More usually, however, the donor and recipient are different individuals, and this is termed allogeneic transplantation. 

Grafting can also provide the monolithic polymers with rather unexpected properties. For example, the two-step grafting procedure summarized in Fig. 7, which involves the vinylization of the pore surface by reaction of the epoxide moiety with allyl amine, and a subsequent in situ radical polymerization of N-isopropylacrylamide (NIPAAm) initiated by azobisisobutyronitrile within these pores leads to a composite that changes its properties in response to external temperature [76]. 

Different types of spacers can be introduced on a matrix by a variety of grafting procedures [32,117]. Normally, the length of a spacer is not more that ten atoms. Longer spacers can cause problems due to their folding. Hou and co-workers [ 118] reported this phenomenon for spacers longer than 12 atoms, which were found to cause a dramatic reduction in the binding capacity of the affinity sup-... 

Ciclosporin, a calcineurin inhibitor, is a potent immunosuppressant useful in the prevention of rejection in organ transplants and grafting procedures. Ciclosporin is markedly nephrotoxic. Vincristine is a vinca alkaloid cytotoxic agent fluorouracil and methotrexate are both antimetabolite cytotoxic agents and bleomycin is a cytotoxic antibiotic. 

Grafting Procedures. In the grafting experiments, two procedures were followed. 

Araki et al. (117) have described a so-called dry-state grafting procedure in which the cellulose is boiled with water and then the water is replaced by various alcohols, also by boiling. The cellulose was then dried and grafted with styrene using both mutual and pre-irradiation methods. The treatment was effective with cotton but only to a small extent with rayon fibers. The order of effectiveness of the solvents used was butanol as the most effective and methanol, water, higher alcohols and ketones as considerably less effective. This is a different order from... 

An electrolytical grafting procedure has been suggested by Epstein, and Bar-Nun (131). During an electrolytic treatment of methyl methacrylate in dilute sulfuric acid in presence of regenerated cellulose film substantial weight increases of the cellulose film were observed. Even extraction with benzene after severe grinding did not result in removal of the ester groups contained in the product. 

The effect of oxygen on the grafting procedure was also examined. Oxygen in the CAS soak had no effect on the percent... 

In order to limit extensive side reactions (advanced destruction of the support-polymer, modification of grafting monomers structure) which usually accompany grafting reactions in electrical discharge conditions, we have elaborated the solid-solid grafting procedure in cold plasma. Thus, the rayon fabric was grafted with halogen and phosphorus containing polymers in... 

Grafting Procedure and Calculation of Percent Grafting. Graft copolymerisation treatment of KPM rayon yarn and jute fiber were carried out in a well stoppered, Erlenmeyar flask. Fifty millimeter CAS solution of known concentration was kept at a desired temperature. One millimeter MMA was added following immediately by 1.0 gm of KPM rayon yarn, after which the contents were stirred intermittently. After the end of the reaction, the flask were removed from the thermostat and methanol was immediately added. 

Both UV and ionizing radiation grafting procedures were modifications of previously reported methods (7,13). Monomers were purchased from Monsanto Chemicals (Australia) Limited and Polysciences Incorporated. Inhibitor was removed prior to reaction by passing the monomer down a column of activated alumina (13). All solvents were AR grade and used without further purification. 

Mechanism of Acid Effect in Cellulose UV Comonomer Grafting Procedure. In the earlier work (7) involving the UV grafting of monomers to cellulose, it was shown that radical sites, where copolymerization can occur, are formed in cellulose either by the direct action of UV on... 

In a similar way, the emergence of nanoparticles having optical and/or electrochemical properties has led to the achievement of new labels for DNA chips. These labels, which have nanometer size, require nucleic acid grafting procedures similar to those performed on a flat surface or on micrometer size beads. 

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