Synthesis and properties of hydroxymethylphosphonic and bishydroxymethylphosphinic acids

Summary By the reaction of phosphorous acid and its salts and of hypophosphorous salts with paraform, hydroxymethylphosphonic acid and its salts and bishydroxymethylphosphinic salts were obtained in 90–93% yield.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1230–1233, July, 1964     

Poly(3-Hydroxybutyrate) Matrices Modified with Iron(III) Complexes with Tetraphenylporphyrin. Analysis of the Structural Dynamic Parameters

The effect of small additions of the iron(III) complex with tetraphenylporphyrin (0–5%) on the structure and properties of ultrathin fibers based on poly(3-hydroxybutyrate) (PHB) was studied by differential scanning calorimetry (DSC), X-ray diffraction analysis (XRD), EPR probe method, and scanning electron microscopy. When tetramethylporphyrin was added to the PHB fibers, the crystallinity significantly increased, and the molecular mobility in the amorphous regions of the polymer decreased. The thermal treatment of the fibers (annealing at 140°C) led to significantly increased crystallinity and decreased molecular mobility in the amorphous regions of the PHB fibers. The addition of tetramethylporphyrin to the PHB fibers led to a sharp decrease in crystallinity. Ozonolysis of the fibers at small treatment times caused a considerable decrease in their molecular mobility (to 5 h), while prolonged ozonolysis led to increased mobility. The obtained fibrous materials have bactericidal properties and will find use in the development of antibacterial and antitumor therapeutic systems.     

Oscillations of a bubble separated from an air cavity under compression caused by magnetic field in a magnetic fluid

Based on the concept of mapping the free surface geometry of a weakly magnetic medium by the topography of isolines of the magnetic field strength magnitude, the shape of the free surface of a magnetic fluid is studied in the static state at two stages: the initial stage, where an annular magnet is moving toward the surface of the magnetic fluid column in a tube, and at the stage where the air cavity is pressed to the bottom. It is shown that the separation of bubbles from the air cavity occurs at the magnet axis in the immediate vicinity of the magnet symmetry plane. A method and an experimental setup are proposed to investigate possible electromagnetic indication of the size of air bubbles formed in the magnetic fluid. The results of an experimental study of bubble separation from an air cavity held in the magnetic fluid and compressed by the pondermotive forces of the magnetic field are discussed. The results may be of importance for designing a new technique for metering small gas shots to a reactor.     

Study of the technological properties of modified urea formaldehyde resin

The technological properties of urea formaldehyde resins modified by polyvinylacetate are presented.