Emission properties, molecular glasses

From these results, and from the reported extrapolated values of 276 °C (syndiotactic) and 126 °C (isotactic) for the glass transition temperatures of PNVC it has been concluded that rotational eclipsing in isotactic NVC sequences is very much more favourable than in corresponding syndiotactic sequences. This contusion is strongly supported by examination of space filling molecular models. Such considerations must be borne in mind when considering the optical and chiroptical properties of carbazole containing polymers and it has to be expected that copolymers of NVC will have fluorescence emission properties that can be related to both main chain tacticity and distribution of monomeric units. Free radically polymerized mixtures of NVC and acrylic derivatives of (—)-menthol have fluorescence spectra... 

Odorant molecules are typically small organic molecules with a molecular weight of 26-300. An odor consists of millions of volatile molecules emitted into the fluid media of air or water. The vapor pressure of a compound is a measure that directly relates to its volatility odorants with high vapor pressures in ambient conditions volatilize readily. Inanimate odor sources passively emit odors animate odor sources may passively or actively emit them. The intensity and chemical nature of both passive and active emission are a function of the properties of the compounds present, the temperature, and the atmospheric pressure. Examples of inanimate passive emission would include an inanimate object such as a glass of wine emitting hundreds of compounds from the fluid surface into the headspace in the immediately vicinity of the fluid." Animate passive emission often occurs as a function of a metabolic process. For example, the odors typically associated with rotting meat are produced and emitted by microbes as a byproduct of metabolism." Mammals emit CO2 and lactic acid as a byproduct of metabolism CO2 and lactic acid may be used by insects, such as mosquitos, to locate mammalian hosts." " In active emission, odors are synthesized and emitted by an animate signaler. Examples... 

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