Separation of motions and vibrational separation of fractions for biocide brass

Topological Data Analysis of Nanoscale Roughness in Brass Samples

“…Note that the treated surfaces were also ground manually by sandpaper and polished, which led to some oriented roughness features (scratches) at the surface, making them anisotropic. Moreover, the sample treated at 70% showed some features (white spots in Figure e) possibly caused by oxidation; oxidation and fraction separation is not an uncommon effect of the sonochemical treatment of brass …”

“…Novel metallic materials, including alloys and composites, are particularly challenging due to the difficulty of predicting their tribological properties . We study brass surfaces in particular due to their relevance to bactericide and antiviral action. − While it is believed that Cu + and Zn + ions are responsible for the bactericide action, there are indications that surface roughness may be involved as well. , The objective of the present paper is to seek similar persistent data structures in roughness data obtained with atomic force microscopy (AFM) and to compare them with relevant more traditional miscroscale and nanoscale roughness parameters.…”

When Bubbles Are Not Spherical: Artificial Intelligence Analysis of Ultrasonic Cavitation Bubbles in Solutions of Varying Concentrations

“…The mathematical method of the separation of fast and slow motions has been successfully applied to study the effects of fast oscillations in various physical systems where fast small amplitude oscillations are present. ,,− In this method, high-frequency low-amplitude vibrations are replaced by an averaged action of a force or of a potential energy field. For bubbles oscillating in the acoustic field created by ultrasound, the effective energy is averaged over the time period of oscillations (for derivation, see the Supporting Information)­ where the dependency R ( t ) is obtained by integrating eq .…”

“…Acoustic treatment of liquids is widely used for such purposes as aeration, vibration-induced phase separation, and acoustic spectral analysis of a fluid in a flow. − During ultrasonic acoustic cavitation, small bubbles in liquid are produced by propagating high-frequency pressure fluctuations. − Newly nucleated bubbles undergo a certain evolution. They often tend to grow, while their size oscillates due to the acoustic excitation causing compressive and tensile stress.…”

“…Following the oscillation stage, bubbles often either decompose into parts or they can destabilize and completely collapse. The bubble collapse is a very rapid process, which results in high velocities of the liquid–gas interface often leading to shock waves (i.e., exceeding the speed of sound in the fluid) and to very high local temperatures (estimated as high as 5000 K) and high pressures, as well as to the fluorescence. − This makes ultrasound useful for the sonochemical treatment of solid materials immersed in water including nanostructuring. , …”