The accurate quantification and delivery of odorant concentrations remain a significant challenge. Traditional methods estimate stimulus intensity based on the amount of odorant in the source, but this does not reflect the actual concentration sent due to variable evaporation rates and delivery devices. This leads to inconsistencies in stimulus delivery, complicating cross-laboratory comparisons, threshold evaluations, and the replication of natural olfactory conditions in the lab. To address this, we present a model based on mass transfer theory to predict the concentration of odorants delivered by a simple and versatile odor delivery system commonly used in insect electrophysiological experiments. The present model, built with adaptable compartments, accounts for airflow, source size, and the physicochemical properties of odorants. It helps to better design and use odor delivery systems, especially for stimuli required to mimic natural odor environments. Calibration uses known partition coefficients. The model also considers the dynamic shape of odor stimuli, which affects neuronal responses and must be carefully interpreted, especially when using tools like photoionisation detectors (PID). This approach was applied to study the impact of a plant volatile known to activate pheromone-sensitive neurons, (Z)-3-hexenyl acetate, on pheromone detection in Agrotis ipsilon moths. While interference occurs in laboratory conditions at 160 ppb, such concentrations are unlikely in natural settings, suggesting these effects are less relevant ecologically.

Olfactory sensitivity during the menstrual cycle. Women were tested for sensitivity to several odorants at ovulation and menstruation. Three involatile esters (pentadecalactone, coumarin, and cinnamyl butyrate) predicted by gas chromatographic data to be strongly retarded by the olfactory mucus showed similar significant changes in sensitivity. By contrast, a more volatile ester (amyl acetate) predicted to diffuse more readily though the mucus showed no such changes. This suggests that variations in olfactory sensitivity observed between ovulation and menstruation depend on odorant volatility and thus may result from peripheral mechanisms limiting the access of odorant molecules to the olfactory receptors. Published in Sensory processes (1978)

В статье представлены результаты экспериментального исследования интенсивности испарения ацетона. Установлено, что экспериментально определенная интенсивность испарения превышает расчетные значения, полученные по существующим методикам. Особое внимание уделено анализу влияния скорости движения воздуха на процесс испарения. При нулевой скорости воздушного потока выявлено максимальное расхождение между экспериментальными и расчетными данными. The article presents the results of an experimental study of the evaporation rate of acetone. It has been established that the experimentally determined evaporation rate exceeds the calculated values obtained using existing methods. Special attention is paid to the analysis of the effect of air velocity on the evaporation process. Maximum discrepancy between experimental and calculated data is revealed at zero air flow velocity.