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Based on Voronoi analysis, the properties related to the near-wall motion of particles in a turbulent boundary layer were experimentally investigated via different release modes, with a friction Reynolds number $Re_\tau =3530$. For high-inertia sand particles with Stokes number $St^+ \sim O(10^2\unicode{x2013}10^3)$ and a volume fraction $\varPhi _v \sim O(10^{-4})$ , particle image tracking velocimetry was used to determine the particle position and near-wall distribution properties. We established three particle release modes, including top-released, bottom overall-released and bottom partially released sand particles, under the same flow field conditions and calculated the differences in particle near-wall clustering and void properties. It was confirmed that wall effects (including collision and strike-splash) have a great influence on particle clustering and void behaviour near the wall. In the top-released sand particle and locally laid sand particle cases, particles bounced off the smooth walls and re-entered the carrier flow, causing significant clustering and sparsing of particles near the walls. In contrast, in the overall sand-laying case where the bottom wall was completely covered with sand particles, there is no apparent cluster or void phenomenon near the wall $(z/\delta and the particles are randomly distributed, due to the combined effect of particle impact and splashing. In addition, the clustering and voids of particles become more pronounced with increasing wall-normal distance in the three release modes, and the particle distribution shows some self-similarity at each flow layer. The probability density function of the concentration of cluster particles decreases following a ' $-5/3$ ' power law. However, due to the particle–wall interaction, the probability density function gradually deviates from the ' $-5/3$ ' power law. [ABSTRACT FROM AUTHOR]

Double quantum barriers were used for improving the retention and endurance characteristics of charge-trapping memory. Findings reveal significantly high temperature retention and cycled retention data.

The nitrogen composition dependence of the characteristics of TaN/HfLaON/[Hf.sub.1-x-y][N.sub.x][O.sub.y]/Si[O.sub.2]/Si MONOS memory devices is discussed. A wider memory window and a smaller high-temperature decay rate are observed in the [Hf.sub.0.3][N.sub.0.2][O.sub.0.5] MONOS devices.

In this study, the pilot apparatus combined with sand filtration, ozonation and ultrafiltration was established. Wastewater from the secondary treatment effluent in the new-developed community was taken as the sample for looking into the feasibility of domestic wastewater reuse and recycling. The test results by sand filtration, sand filtration/ultrafiltration, sand filtration/ozonation, and sand filtration/ultrafiltration/ozonation were compared for looking for appropriate treatment processes applied in the domestic wastewater reuse and recycling. Finally, cost analysis was carried out and sand filtration/ozonation process was suggested to be one of the best processes. The total cost is about 0.1–0.32 $USD per cubic meter of produced water by considering the capital and operation cost for five years in the small domestic wastewater treatment plant (50–750 CMD). [ABSTRACT FROM AUTHOR]