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In the set of wind instruments (aerophones) there is one that, despite not being as popular as the flute or the saxophone, frequently figures in concert music; in orchestras and chamber performances: the bassoon. It has a distinctive, nasal and unmistakable sound. In this work we present some aspects of the physics and music of the bassoon. We selected some sites with songs that show the sound of the bassoon. Experiments were carried out to study sound waves, sound spectra, sound pressure levels, sound radiation as well as the psychoacoustics of the instrument. In the analysis of the experimental results, the programs Praat, dBTrait and dBInside were used. We observed that the bassoon can be considered a harmonic instrument and that the intensity relationship between the fundamental and the harmonics, including their presence or absence, depends on the emitted frequency, the measurement position, the time of emission of the note and how the sound was captured (including or not the attack and decay). The experimental processes used can be applied to the study of the physics of other musical instruments, allowing the observation of different types of sound sources and thus contributing to the motivation in physics and music teaching. [ABSTRACT FROM AUTHOR]

In recent years the use of ultrasound in the processing of food has increased due to the advantages it presents over conventional processes by reducing time and temperature, effective mixing, increased mass and energy transfer, reduction of the thermal and concentration gradients, selective extraction, a faster response to the control of extraction processes, increase of the production rate, elimination of microorganisms and enzymes without destroying the nutrients of the food. In addition, to be considered a clean technology, applicable in the different phases of food processing such as: drying, homogenization and extraction. Ultrasound of low power (high frequency) is used to monitor the composition and physicochemical properties of food components and high power (low frequency) induces mechanical, physical chemical and biochemical changes by the action of cavitation, which supports Many food processing operations. This review summarizes the application of ultrasound in the processing of homogenization, extraction and drying in food, in order to know the general aspects: definition, mechanisms, effects; applications and future application trends in the food industry. [ABSTRACT FROM AUTHOR]