Results 1 to 10 of about 984,214 (255)

Acoustic blackbody through instability-induced softening

Communications Physics
Perfect wave absorption across all wavelengths is forbidden by the causality principle. Here we demonstrate an approach that circumvents this fundamental limitation in acoustics by coupling unstable components to achieve zero static modulus.
Min Yang, Sichao Qu, Nicholas Fang, Shuyu Chen   +3 more
doaj   +1 more source

Wavefront manipulation by acoustic metasurfaces: from physics and applications

Nanophotonics, 2018
Molding the wavefront of acoustic waves into the desired shape is of paramount significance in acoustics, which however are usually constrained by the acoustical response of naturally available materials.
Liang Bin, Cheng Jian-chun, Qiu Cheng-Wei   +2 more
doaj   +1 more source

The Acoustic Characterization of Broom Fibers

Journal of Natural Fibers, 2017
Natural materials are becoming a valid alternative to traditional synthetic ones for sound absorption applications. In this paper, the acoustic properties of broom fibers are reported and discussed.
Umberto Berardi, Gino Iannace, Maria Di Gabriele   +2 more
doaj   +1 more source

Utilizing Agricultural Waste Materials for the Development of Sustainable Sound Absorption Materials [PDF]

Nature Environment and Pollution Technology
Environmental pollution is escalating due to inadequate waste management, with the open burning of agricultural waste being a significant contributor. This process releases various harmful gases into the environment.
Venkatesan B., Kannan V., Raja Priya P. and Karthiga Shenbagam N
doaj   +1 more source

Sound Diffusers with Fabric Covering

Archives of Acoustics, 2013
Fabric covering is often used by designers, as it can easily mask acoustic structures that do not match an interior. However, in the case of sound diffusers based on change in the phase of the reflected wave, the use of fabric covering is not without ...
Tadeusz KAMISIŃSKI, Krzysztof BRAWATA, Adam PILCH, Jarosław RUBACHA, Marcin ZASTAWNIK   +4 more
doaj  

The Effect of Geometrical and Material Modification of Sound Diffusers on Their Acoustic Parameters

Archives of Acoustics, 2013
Sound diffusers, in particular those based on changes in the phase of the reflected wave (Schroeder diffusers), have recently gained greatly in popularity in acoustics as an effective means to eliminate defects and improve the acoustic performance of ...
Adam PILCH, Tadeusz KAMISIŃSKI
doaj  

Granular Pumice Stone: A Natural Double-Porosity Sound-Absorbing Material

Buildings
Pumice forms when a volcanic explosion ejects highly pressurized, superheated rock, rapidly cooling and depressurizing, resulting in a porous structure.
Jorge P. Arenas, Claudio C. Parra, Juan Rebolledo, Rodolfo Venegas   +3 more
doaj   +1 more source

Modelling of Green function in a rectangular room based upon the geometrical-filtration model

Archives of Acoustics, 2014
Significant problem in room acoustic is evaluating an acoustic quality of projected and modernized rooms. Estimation of room impulse response giving posibility to evaluate the subjective and objective room acoustic properties and hence to run the room ...
R. Marczuk, L. Majkut
doaj  

Broadband low-frequency sound absorption and high insulation in a clay-cement composite with hydrogel-foaming engineered gradient porosity

Scientific Reports
Urban noise pollution has emerged as a critical environmental issue, driving demand for high-performance cementitious materials with broadband sound absorption capabilities.
Zhenhua Hou, Zhenfu Zhou, Xingyu Chen, Ke Zhang, Hao Li, Yuxiang Zheng, Libo Wang   +6 more
doaj   +1 more source

Design and Validation of a PU-Six-Cavity Helmholtz Metamaterial Composite Acoustic Package for Broadband Noise Reduction in Commercial Vehicle Cabs. [PDF]

Materials (Basel)
Cai C, Duan Y, Wang T, Wang A, Wang X, Shi Y, Xiao X, Huang Y.   +7 more
europepmc   +1 more source