Extraction oxide moieties

Selective Extraction of Actinides by Calixarenes Bearing Phosphine Oxide Moieties... 

Extraction of thorium nitrate and europium nitrate 0 0 4 M) from 1 M HN03 into dichloromethane was carried out for 19 calixarenes totally or partially substituted on the lower rim by phosphine oxide moieties (CPol-CPol7-CPol9-CPo20) and for one calixarene substituted by phosphinate (CP0I8) (see Section 4.7).IM 152 154... 

The replacement of the phenyl groups on the phosphine oxide moieties by n-butyl groups leads to a complete loss of extraction. Increasing the length of the chain linking the calixarene to the phosphine oxide moieties leads to a decrease of extracting ability of both tetramer and hexamer (Table 4.23). The selectively substituted... 

Compared with the unit model and classical extractant, tri- -octylpho-sphine oxide (H5.26) showed remarkable selectivity for thorium(iv) and uranyl(vi) caions. The spacer length between the phosphine oxide moiety and the pillar[5]arene also affected the extraction efficiency. As the length of the spacer increased, the extraction efficiency of these cations increased, per-Methylated pillar[5]arene H5.2 did not extract these cations, therefore the 10 phosphine oxide moieties on the pillar[5]arene rim acted as an extractant. The efficiency was remarkably decreased in the unit model, indicating that the pillar[5]arene cavity is required to extract these cations efficiently. H5.26... 

Extractants derived from the carbamoylmethylphosphoryl moiety (CMP) were studied in the phosphonate, phosphinate, and phosphine oxide classes. Our studies focused on dihexyl-N,N-diethylcarba-moylmethylphosphonate, DHDECMP, hexyl hexyl-N,N-diethylcarbamoyl-methylphosphinate, HHDECMP, and octyl(phenyl)-N,N-diisobutylcarba-moylmethylphosphine oxide, 0D[ IB]CMP0. The three types of CMP extractants were compared on the basis of nitric acid and extractant dependencies for Am(III), solubility of complexes on loading with Nd(III) and U(VI), and selectivity over fission products. On the basis of the above data two conceptual flowsheets were developed. The first flowsheet involves the extraction of all of the actinides from HLLW using 0.4 M 0D[IB]CMP0 in DEB. The second flowsheet involves the extraction of all of the actinides from dissolved spent LWR fuel using 0.8 M DHDECMP in DEB. 

Graft copolymers were prepared by polymerizing ethylene oxide onto the PVN polyradical anion (10), The latter was obtained by reaction of PVN with cesium in tetrahydrofuran solution. The copolymers were extracted with water to remove the PEO homopolymer which was formed as a byproduct. Experimental details and evidence for bond formation between ethylene oxide and the aromatic moiety were presented elsewhere (//). 

The pink cured meat pigment mononitrosylhemochrome is a complex of nitric oxide (NO), ferrous heme iron, and heat-denatured globin protein (Table F3.2.1). The pink nitrosylheme (NO-heme) moiety may be extracted from the protein in aqueous acetone and quantitated by A540 (see Basic Protocol 1). The percent nitrosylation may be determined from measurement of ppm NO-heme relative to ppm total acid hematin (hemin) extracted in acidified acetone (see Basic Protocol 2), since NO-heme is completely oxidized to hemin in acid solution (i.e., 1 ppm NO-heme = 1 ppm hemin). 

Hornsey (1956) also found that extraction with an acidified 80% acetone solution for 1 hr gave a hemin solution, derived from oxidation of the heme moiety of both NO-heme and non-nitrosylated heme pigments. Hemin absorption spectra exhibited distinct peaks at 512 and 640 nm. Hornsey (1956) used the A640 of sample filtrates as a measure of the total heme pigments. Solutions of both hemin and NO-heme in 80% acetone conformed with Beer s... 

Other preliminary experiments on alkali lignin included oxidations by barium peroxide and alkali (5, 6), alkali fusion, and alkali fusions in the presence of calcium peroxide, sodium borate perhydrate, and monopersulfate compound. Ether extractives and water extractives were examined, but in all cases too many of the oxidation products obtained were new and unidentifiable, and it was impossible to evaluate the experiments adequately with the available techniques. Vanillic acid appeared to be the chief oxidation product under conditions which did not demethylate further or destroy the aromatic nature of the oxidation products. Some oxidation conditions yielded p-hydroxybenzyl moieties as products, and some gave no trace of these products whatever. More detailed studies of the ether-insoluble, water-soluble components of the several oxidation mixtures were postponed until adequate procedures were developed for analytical isolation and identification. 

Biogenic amines, such as histamine [131], adenine [132], dopamine [133] and melamine [134], have been determined using chemosensors combining MIP recognition and PM transduction at QCM. Electronically conducting MIPs have been used in these chemosensors as recognition materials. Initially, functional electroactive bis(bithiophene)methane monomers, substituted either with the benzo-18-crown-6 or 3,4-dihydroxyphenyl, or dioxaborinane moiety, were allowed to form complexes, in ACN solutions, with these amines as templates. Subsequently, these complexes were oxidatively electropolymerized under potentiodynamic conditions. The resulting MIP films deposited onto electrodes of quartz resonators were washed with aqueous base solutions to extract the templates. 

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