The reconstruction of photoacoustic images typically neglects the effect of acoustic absorption on the measured time domain signals. Here, a method to compensate for acoustic absorption in photoacoustic tomography is described. The approach is based on time-reversal image reconstruction and an absorbing equation of state which separately accounts for acoustic absorption and dispersion following...

A hybrid acoustic metamaterial is proposed as a new class of sound absorber, which exhibits superior broadband low-frequency sound absorption as well as excellent mechanical stiffness/strength. Based on the honeycomb-corrugation hybrid core (H-C hybrid core), we introduce perforations on both top facesheet and corrugation, forming perforated honeycomb-corrugation hybrid (PHCH) to gain super bro...

BACKGROUND Although calcium inhibits zinc bioavailability in rats, especially from high-phytate diets, the effect of calcium on zinc absorption by humans from practical diets remains unclear. OBJECTIVE The objective was to test the inhibitory effect of dietary calcium, in Western diets with high and low phytate content, on zinc absorption. DESIGN Using a 2 x 2 factorial design, zinc absorpt...

the seismic performance of hybrid braces composed of steel and shape memory alloy (sma) was investigated in this paper. six types of hybrid braces were used, constituted by sma content of 0, 20, 40, 60, 80, and 100%. a nonlinear dynamic analysis was performed under el centro earthquake records, with the maximum acceleration of 0.6g and 0.9g. our results showed that the seismic performance, i.e....

Dynamic Ratcheting (DR) is a nonlinear dynamic phenomenon occurring in hysteretic damping systems. It means the structural plastic deformation increases asymmetrically in successive cycles under an earthquake excitation. Although it is generally recognized that DR is closely related to the frequency contents of an earthquake excitation applied to thestructure, no targeted analysis has bee...

Absorption and reflectance spectra of maple (Acer platanoides), cotoneaster (Cotoneaster alaunica), dogwood (Cornus alba) and pelargonium (Pelargonium zonale) leaves with a wide range of pigment content and composition were studied in visible and near-infrared spectra in order to reveal specific anthocyanin (Anth) spectral features in leaves. Comparing absorption spectra of Anth-containing and ...

Baking quality of 11 winter wheat varieties was studied at the Jõgeva Plant Breeding Institute during 5 years (2005–2009). Protein content, farinograph absorption, dough stability time and loaf volume were examined in this study. The varieties were divided into clusters according to the average value of quality characteristics and coefficient of variation. Ada, Tarso, Portal, Ramiro had high pr...

We use the technique of terahertz time-domain spectroscopy to investigate the absorption and dispersion of spectrally dense methyl halide vapors, particularly in the lowand high-frequency spectral wings. For the first time to our knowledge, it is possible to observe essentially zero-frequency absorption resulting from molecular tunneling between the two states of symmetry simultaneously, with a...