Optimization of an absorbing surface with 2D Helmholtz resonators for reduced sensitivity to the incidence angle

2021 ◽  
Vol 263 (4) ◽  
pp. 2114-2125
Author(s):  
Diana Maria Garza-Agudelo ◽  
Vicente Cutanda Henriquez ◽  
Cheol-Ho Jeong ◽  
Peter Risby Andersen
Keyword(s):  
Absorption Coefficient ◽  
Incidence Angle ◽  
Low Frequency ◽  
Large Degree ◽  
Acoustic Performance ◽  
Helmholtz Resonators ◽  
Sound Control ◽  
Extended Frequency ◽  
High Absorption Coefficient ◽  
High Absorption

It has been shown in several recent publications that acoustic materials consisting of a combination of resonators tuned to different frequencies can render high absorption coefficient values over an extended frequency range while maintaining compactness. This makes them attractive solutions for applications in which low frequency sound control is needed, and/or when there are significant space constraints. Nevertheless, the acoustic performance of these surfaces varies with the angle at which a wave impinges on the surface. The changes in the absorption characteristics with the incidence angle occur both on the maximum absorption coefficient, and on the effective frequency bandwidth. Numerical optimization is a tool that can help realize designs with a large degree of geometrical freedom, and using this framework we have demonstrated an array of coupled 2D Helmholtz resonators that is less sensitive to changes in the incidence angle.

Analysis about the Effect on the Design of the Diffusers

2012 ◽  
Vol 174-177 ◽  
pp. 2016-2019
Author(s):  
Hui Yu Chen ◽  
Jing Gong
Keyword(s):  
Body Size ◽  
Absorption Coefficient ◽  
High Frequency ◽  
Large Body ◽  
Low Frequency ◽  
Groove Depth ◽  
The Body ◽  
Frequency Sound ◽  
High Absorption Coefficient ◽  
High Absorption

In order to study the effect of the diffusers,there has been designed a variety of diffusers.If groove depth is large , the diffuser will become a high absorption coefficient, low-frequency sounds will reduce significantly. So we have spread the body size nested within each other, a small has been nested in a large body .The smaller parts expand of high-frequency sound, the larger parts for low-frequency sound, so over a wide frequency band can been spreading.

scholarly journals Rational Design of Aqueous Conjugated Polymer Nanoparticles as Potential Theranostic Agents of Breast Cancer

2021 ◽  
Author(s):  
Panagiota Koralli ◽  
Spyridon Tsikalakis ◽  
Maria Goulielmaki ◽  
Stella Arelaki ◽  
Janina Müller ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Absorption Coefficient ◽  
Conjugated Polymer ◽  
Rational Design ◽  
Polymer Nanoparticles ◽  
Quantum Yields ◽  
Conjugated Polymer Nanoparticles ◽  
Theranostic Agents ◽  
High Absorption Coefficient ◽  
High Absorption

Conjugated polymer nanoparticles (CPNs) have emerged as a new promising class of cancer theranostic agents due to their desirable optical features, such as high absorption coefficient and photoluminescence quantum yields,...

Mechanical and optical behaviors: strain synergy effects in high temperature phase oxide of lead

2021 ◽  
Author(s):  
Qidong Kang ◽  
Fei Yang ◽  
Xinyu Zhang ◽  
Ziyu Hu
Keyword(s):  
High Temperature ◽  
Absorption Coefficient ◽  
Bulk Material ◽  
High Temperature Phase ◽  
Temperature Phase ◽  
Synergy Effects ◽  
High Absorption Coefficient ◽  
Very High ◽  
High Absorption

Since lead has a very high absorption coefficient μ, that the radiations from within the bulk material do not penetrate the layers. While, the oxygen and water (O2 and H2O)...

9.6%- Efficient All-Inorganic Sb2(S,Se)3 Solar Cell with MnS Hole-Transporting Laye

2022 ◽  
Author(s):  
Chen Qian ◽  
Jianjun Li ◽  
Kaiwen Sun ◽  
Chenhui Jiang ◽  
Jialiang Huang ◽  
...  
Keyword(s):  
Solar Cell ◽  
Absorption Coefficient ◽  
Light Harvesting ◽  
Low Cost ◽  
The Poor ◽  
Hole Transporting ◽  
Low Toxic ◽  
High Absorption Coefficient ◽  
Poor Stability ◽  
High Absorption

Antimony selenosulfide, Sb2(S,Se)3, has emerged as a promising light-harvesting material for its high absorption coefficient, suitable bandgap, low-toxic and low-cost constituents. However, the poor stability and high cost of widely...

scholarly journals Oxidation of 3-amino-1-phenylprop-1-enes by monoamine oxidase and their use in a continuous assay of the enzyme

1988 ◽  
Vol 256 (3) ◽  
pp. 911-915 ◽  
Author(s):  
C H Williams ◽  
J Lawson ◽  
F R C Backwell
Keyword(s):  
Monoamine Oxidase ◽  
Absorption Coefficient ◽  
Mitochondrial Protein ◽  
Bovine Liver ◽  
Spectrophotometric Assay ◽  
Monoamine Oxidase A ◽  
Monoamine Oxidase B ◽  
High Absorption Coefficient ◽  
Continuous Assay ◽  
High Absorption

3-Amino-1-phenylprop-1-ene (cinnamylamine) and some derivatives were examined as substrates for monoamine oxidases A and B in mitochondria. All of the amines examined were readily oxidized by monoamine oxidase B but much less readily by monoamine oxidase A. E-Cinnamylamine was found to have Km 0.025 mM and Vmax. 3.9 nmol/min per mg of mitochondrial protein. Corresponding values with monoamine oxidase A were 0.026 mM and 0.85 nmol/min per mg respectively. Despite their different stereochemistry, E- and Z-N-methylcinnamylamines were almost equally effective as substrates for monoamine oxidase B. The characteristic u.v. absorbance and high absorption coefficient of cinnamaldehyde, the product produced by enzymic oxidation of cinnamylamine, is utilized in a sensitive continuous spectrophotometric assay for both enzymes in the rat and for the assay of a purified monoamine oxidase B from bovine liver.

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