The impact of a slug of dry sand particles against a metallic sandwich beam or circular sandwich plate is analysed in order to aid the design of sandwich panels for shock mitigation. The sand particles interact via a combined linear-spring-and-dashpot law whereas the face sheets and compressible core of the sandwich beam and plate are treated as rate-sensitive, elastic–plastic solids. The major...

Water-saturated column experiments were conducted to investigate the effect of input concentration (C₀) and sand grain size on the transport and retention of low concentrations (1, 0.01, and 0.005 mg L⁻¹) of functionalized ¹⁴C-labeled multi-walled carbon nanotubes (MWCNT) under repulsive electrostatic conditions that were unfavorable for attachment. The breakthrough curves (BTCs) for MWCNT typi...

The viability of base-treated juniper fiber (BTJF) media for removing toxic heavy metals (Cd2+, Cu2+, Pb2+, Zn+) in stormwater runoff was investigated. The sorption ability ofthe BTJF for all metals was much higher than that of untreated juniper. The affinity sequence of both materials, BTJF and untreated juniper, was Pb > Cu > Zn:,. Cd. This order is explained by the hydrolysis constants for e...

Surfactant-enhanced remediation technology has shown promising potential for removing residual organics from contaminated soils and groundwater. Using a homologous series of cationic surfactants, alkylpyridinium bromide, it was found that the molar solubilization ratio (MSR) for naphthalene decreases with decreasing carbon number in the hydrophobic tail. In contrast, with nonylphenyl ethoxylate...

This work investigated the effect of different surface modification methods, including oxidization, surfactant coating, and humic acid coating, on single-walled carbon nanotube (SWNT) stability and their mobility in granular porous media under various conditions. Characterization and stability studies demonstrated that the three surface modification methods were all effective in solubilizing an...

Sand dripping in 1 dimensional Sand Pile Model is rst studied. Patterns and signals appear. Their behaviors and interactions are explained and asymptotic approximations are made. The total collapsing time of a single stack of sand is linear in function of the number of grains.

[1] The transport and deposition behavior of pathogenic Escherichia coli O157:H7 was studied under unfavorable electrostatic conditions in saturated quartz sands of various sizes (710, 360, 240, and 150 mm) and at several flow rates. At a given velocity, column effluent breakthrough values for E. coli tended to decrease in magnitude, and concentration curves became more asymmetric with decreasi...

What is a bobtail squid? Euprymna scolopes (Figure 1) is a small sepiolid squid, or bobtail squid, occurring in the marine coastal environment of the Hawaiian archipelago. Whereas most other squid are always out and about, the bobtail squid buries itself in the sand during its daylight quiescent period. Then, at night, individuals of this species emerge from the sand to forage on prey, such as ...

The mobility of metazachlor [2-chloro-N-(pyrazol-1-ylmethyl)acet-2',6'-xylidide] in sand soil and loamy sand soil was studied in a soil column under laboratory conditions. Commercial metazachlor formulation (Metazachlor 500 suspension concentrate (SC)) and metazachlor immobilized in alginate matrix were used for leaching experiment. The initial concentration of metazachlor in soil for both form...

Transmissible spongiform encephalopathies (TSEs, prion diseases) are a class of fatal neurodegenerative diseases affecting a variety of mammalian species including humans. A misfolded form of the prion protein (PrP(TSE)) is the major, if not sole, component of the infectious agent RecentTSE outbreaks in domesticated and wild animal populations have created the need for safe and effective dispos...