Related Experiment Video

Updated: Dec 29, 2025

Production and Testing of Moisture Behavior and Thermal Properties of Rapeseed Straw and Ganoderma resinaceum Mycelium Bio-Composites
09:39

Production and Testing of Moisture Behavior and Thermal Properties of Rapeseed Straw and Ganoderma resinaceum Mycelium Bio-Composites

Published on: September 5, 2025

420

Innovative Use of Sheep Wool for Obtaining Materials with Improved Sound-Absorbing Properties

Simona Ioana Borlea Mureşan1, Ancuţa-Elena Tiuc1, Ovidiu Nemeş1,2

  • 1Faculty of Materials and Environmental Engineering, Technical University of Cluj-Napoca, 28 Memorandumului Street, 400114 Cluj-Napoca, Romania.

Materials (Basel, Switzerland)
|February 9, 2020
PubMed

Keywords:
sheep wool recovery, acoustic materials, sound absorption coefficient

More Related Videos

Twin-Screw Extrusion Process to Produce Renewable Fiberboards07:21

Twin-Screw Extrusion Process to Produce Renewable Fiberboards

Published on: January 27, 2021

6.9K
Author Spotlight: A Stable Phantom Material for Optical and Acoustic Imaging04:54

Author Spotlight: A Stable Phantom Material for Optical and Acoustic Imaging

Published on: June 16, 2023

3.6K

Related Concept Videos

Thermal Insulation in Masonry Walls01:22

Thermal Insulation in Masonry Walls

In hot, dry climates, the thermal mass of masonry walls can be beneficial, absorbing heat during the day and releasing it at night, thereby stabilizing indoor temperatures. However, in most other climates, additional insulation is necessary to enhance thermal resistance.
External insulation can be applied using an Exterior Insulation and Finish System (EIFS), which involves affixing panels of plastic foam to the wall and covering them with a polymeric stucco reinforced with glass fiber mesh....
418
Sound as Pressure Waves01:17

Sound as Pressure Waves

Sound waves, which are longitudinal waves, can be modeled as the displacement amplitude varying as a function of the spatial and temporal coordinates. As a column of the medium is displaced, its successive columns are also displaced. As the successive displacements differ relatively, a pressure difference with the surrounding pressure is created. The gauge pressure varies across the medium.
The pressure fluctuation depends on the difference in displacements between the successive points in the...
4.3K
Sound Waves: Interference00:53

Sound Waves: Interference

Sound waves can be modeled either as longitudinal waves, wherein the molecules of the medium oscillate around an equilibrium position, or as pressure waves. When two identical waves from the same source superimpose on each other, the combination of two crests or two troughs results in amplitude reinforcement known as constructive interference. If two identical waves, that are initially in phase, become out of phase because of different path lengths, the combination of crests with troughs...
4.4K
Perception of Sound Waves01:01

Perception of Sound Waves

The human ear is not equally sensitive to all frequencies in the audible range. It may perceive sound waves with the same pressure but different frequencies as having different loudness. Moreover, the perception of sound waves depends on the health of an individual's ears, which decays with age. The health of one's ears may also be affected by regular exposure to loud noises.
The pitch of a sound depends on the frequency and the pressure amplitude of the source. Two sounds of the same...
5.4K
Sound Waves: Resonance01:14

Sound Waves: Resonance

Resonance is produced depending on the boundary conditions imposed on a wave. Resonance can be produced in a string under tension with symmetrical boundary conditions (i.e., has a node at each end). A node is defined as a fixed point where the string does not move. The symmetrical boundary conditions result in some frequencies resonating and producing standing waves, while other frequencies interfere destructively. Sound waves can resonate in a hollow tube, and the frequencies of the sound...
3.1K
Sound Intensity00:58

Sound Intensity

The loudness of a sound source is related to how energetically the source is vibrating, consequently making the molecules of the propagation medium vibrate. To measure the loudness of a source, the physical quantity of interest is the intensity. This is defined as the energy emitted per unit of time per unit of area perpendicular to the sound wave's propagation direction. Since the total energy is greater if the source vibrates for a longer duration and over a larger area, dividing the...
4.6K