Reference

Relationships between toxicity and structure of aliphatic nitriles

Relationships between toxicity and structure of aliphatic nitriles. Johannsen, Frederick R.; Levinskas, George J. (Dep. Med. Environ. Health, Monsanto Co., St. Louis, MO 63167, USA). Fundam. Appl. Toxicol., 7(4), 690-7 (English) 1986. CODEN: FAATDF. ISSN: 0272-0590. DOCUMENT TYPE: Journal CA Section: 4 (Toxicology) A retrospective structure-activity relationship (SAR) comparison was undertaken of several of the toxicol. properties (acute and subchronic toxicity, teratogenicity, and biochem. mechanism studies) of a series of structurally similar aliph. nitriles based on available published data. Members of this chem. class included several mononitriles (aceto- [75-05-8], propio- [107-12-0], butyro- [109-74-0], and acrylonitrile [107-13-1]), dinitriles succino- [110-61-2] and adiponitrile [111-69-3]), and cyanohydrin derivs. (lactonitrile [78-97-7] and acetone cyanohydrin [75-86-5]). Broadly defined, retrospective SAR anal. suggested that the toxicol. profiles of this group of aliph. nitriles were similar; however, unique differences were obsd. within each of the toxicity categories and nitril subclasses as the toxicol. focus narrowed. Addnl., the toxicol. properties assocd. with acetonitrile, the 1st of this chem. similar series, were unique and quite different from others within the homologous series. Finally, knowledge regarding the mechanism of toxicol. action provided valuable information in relating toxicol. properties among the aliph. nitriles.

Direct thermal measurement of adiabatic dendritic coarsening

Direct thermal measurement of adiabatic dendritic coarsening. Glicksman, M. E. (Mater. Eng. Dep., Rensselaer Polytech. Inst., Troy, NY 12181, USA). NATO ASI Ser., Ser. E, 114(Sci. Technol. Undercooled Melt), 254-6 (English) 1986. CODEN: NAESDI. DOCUMENT TYPE: Journal CA Section: 56 (Nonferrous Metals and Alloys) Dendritic arm spacings change in the solidification of an undercooled melt, involving local rearrangements such as local melting and coarsening of side arms, as diffusion coarsening similar to Ostwald ripening except that the diffusing quantity is enthalpy, not solute. The av. structure length grows as time to the cube-root powder. Under adiabatic solidification conditions the recalescence temp. asymptotically approaches the bulk m.p. After rapid solidification of a melt from the nucleation temp., a vol. fraction of solid is established and maintained const. by the adiabatic constraint. The resistance of a Pt thermometer with a resoln. of 10-4 K is monitored to indicate a transient temp. increase followed by a long steady-state temp. increase which is assocd. with the microstructure coarsening. The temp. rise is calcd. as a function of materials consts. (solid-liq. surface energy, molar vol. of solid, and thermal diffusivity), and rate const. to calc. the structure coarsening. The recalescence was monitored for 3 models: bcc. 4-fold dendrites of succinonitrile [110-61-2]; hexagonal flat snow-flake dendrites of H2O; and branchless needles of ethylene carbonate [96-49-1]. The chaotic pattern is indicated by cyclohexanol [108-93-0] dendrites.