Calibration-free infrared absorption spectroscopy using cantilever-enhanced photoacoustic detection of the optical power.

We report on sensitive tunable laser absorption spectroscopy using a multipass gas cell and a solid-state photoacoustic optical power detector. Unlike photoacoustic spectroscopy (PAS), this method readily allows a low gas pressure for high spectral selectivity and a free gas flow for continuous measurements. Our photoacoustic optical power detector has a large linear dynamic range and can be used at almost any optical wavelength, including the middle infrared and THz regions that are challenging to cover with traditional optical detectors.

Recovery of short-chain organic acids (SCOAs) obtained from anaerobic fermentation process.

Short-chain organic acids (SCOAs) are the intermediates in the anaerobic fermentation process, and can be used in food, textile, and pharmaceutical industries to produce different end use products. SCOAs can be separated, purified, and concentrated by different processes, such as distillation, extraction or membrane-based systems. SCOAs production adds more profitable possibilities to an acidic fermentation process by integration these marketable acids as highly concentrated mixtures with other refinery processes.

Reference-free dual-comb spectroscopy with inbuilt coherence: publisher's note.

This publisher's note contains a correction to Opt. Lett.49, 2473 (2024)10.

High-Pitched Sound is Open and Low-Pitched Sound is Closed: Representing the Spatial Meaning of Pitch Height.

Research shows that high- and low-pitch sounds can be associated with various meanings. For example, high-pitch sounds are associated with small concepts, whereas low-pitch sounds are associated with large concepts. This study presents three experiments revealing that high-pitch sounds are also associated with open concepts and opening hand actions, while low-pitch sounds are associated with closed concepts and closing hand actions.

Is Front associated with Above and Back with Below? Association between Allocentric Representations of Spatial Dimensions.

Previous research has revealed congruency effects between different spatial dimensions such as right and up. In the audiovisual context, high-pitched sounds are associated with the spatial dimensions of up/above and front, while low-pitched sounds are associated with the spatial dimensions of down/below and back. This opens the question of whether there could also be a spatial association between above and front and/or below and back.