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Three water-soluble polymers containing linear alkyl monool, 1,2-diol, and 1,2,3-triol groups, mostly on the primary amines of polyethylenimine, were synthesized, characterized, and tested for their ability to recover boric acid. The boron-binding capacities of these polymers and the backbone polyethylenimine were determined by titration, ultrafiltration, and inductively coupled plasma/ atomic emission spectroscopy analysis. At low boron concentrations, the 1,2,3-triol polymer performed better than the 1,2-diol, whereas at high boron concentrations, the 1,2-diol outperformed the 1,2,3-triol.11 B-NMR spectroscopy and retention studies with various salt concentrations indicated that boron interacted with these two polymers by means of ion pairing with the protonated amines and by borate ester formation. For the monool and the polyethylenimine backbone, the mechanism for boron binding was ion pairing only. These polymers are under consideration for the selective recovery and recycling of enriched boric acid used in the primary coolant loop of pressurized water nuclear reactors.

PS-100 spectrometer, and the samples contained Me4Si as internal standards.(1) (l-Bromo-2,2,2-trifluoroethyl)sulfur Pentafluoride. In a typical reaction a 10-mL stainless-steel Hoke cylinder was charged with 10 mmol of SF5CH=CF2 and 11.5 mmol of Br2 and then placed in a 110 °C oven for 24 h. The cylinder was cooled to room temperature and the volatile material condensed onto Hg contained in a 50-mL Pyrex reactor to remove unreacted Br2. After being shaken for 10 min, the remaining mixture was fractionated by °C trap was empty, and the -80 and -95 °C traps contained impure product. The -196 °C trap contained 1.5 mmol of a material identified as FCH(Br)CF3. The -80 and -95 °C traps were combined, and final purification accomplished by gas chromatography, yielding 6.17 mmol (61.7%) of SF6CH(Br)CF3.

SYNOPSIS Abnormalities of the innervation of the oesophagus have been shown in 18 out of 20 unselected diabetics without clinical dysphagia or neuropathy. The changes appear to be in the axons of the extrinsic and intrinsic parasympathetic fibres. It is probable that, as in the peripheral nerves, the major changes are in the Schwann cells, although here the affected fibres are unmyelinated.

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