0000000000172037
AUTHOR
Thomas Martin
Microphase separation upon crystallization of small amphiphilic molecules: ‘low’ temperature form II of sodium benzoate (E 211)
A so far unknown low temperature polymorph (form II crystallized at 350 °C) of the common food preservative sodium benzoate (NaBz; E 211) could be crystallized by annealing (7 days) of the poorly crystalline technical material. Its crystal structure was solved by indexing a tiny single crystal by electron diffraction followed by structure solution and refinement applying powder X-ray diffraction (PXRD). The new polymorph shows many structural similarities to form I (crystallized at 420 °C). Both form I and II are the result of a microphase separation: the structures consist of pseudo-hexagonal packings of rod-shaped micelles where the core consists of sodium cations being coordinated by the…
Modular Wear Facet Nomenclature for mammalian post-canine dentitions
Dental wear facets on the occlusal surface of premolars and molars are traces of their main function, the mastication and therefore reflect masticatory movements and also paramasticatory (i.e. non-dietary use of teeth) behavior. Here we present the Modular Wear Facet Nomenclature applicable to most mammalian dentitions. Topographic positions of wear facets in relation to the major cusps and crests of the teeth are used to designate the areas of the occlusal surface the facets occupy (e.g. their mesial, distal, lingual, or buccal position). Previous published systems for labeling wear facets have been inconsistent with each other. Therefore, we provide a synoptic review of the most widely-us…