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Attapulgite (ATT) is a naturally rigid reinforcing filler. In this present study, ATT was first purified, and varying amounts of purified ATT was added to polylactic acid (PLA) to modify PLA through a melt-blending technique. The objective was to determine how the content of ATT affected the characteristics of the ensuing PLA/ATT nanocomposites: morphology, mechanical and thermal properties. Filling PLA with ATT increased both the thermal and mechanical properties, but too much ATT was not beneficial as the effect was to decrease both properties. Energy dispersive spectroscopy indicated that the percentage of Si element increased with the amount of ATT, but more than 10 wt % ATT led to a poor ATT distribution in the nanocomposites.

Organic molybdenum (e.g., molybdenum dialkyldithiocarbamate, Mo-DTC) is a typical additive for liquid lubricants which can produce a significant anti-wear role with only a minor addition. I...

Impact experiments of large-caliber PELE with various inner-outer diameter ratio perforating RHA plate at low velocity were performed. Experimental results showed the size of perforated holes on plate, average diameter of damage area on witness plate, and number of behind-armor fragments will increase as d/D increasing from 0.72 to 0.84. Expansion and fragmentation of large-caliber PELE in this condition were also numerically studied with ANSYS Autodyn. Then, an analytical model accounting for an additional radial shock wave was presented to predict radial expansion velocity and fragmentation of jacket, as well as an empirical approach to estimate diameter of damage area. Calculation results by these approaches were in good agreement with experiments and numerical simulations. Further discussion revealed that Shock/rarefaction wave interactions behavior varying with inner-outer diameter ratio is an important mechanism resulting in different lateral effect by PELE projectiles with various configurations. Keywords: PELE, Enhanced lateral effect, Penetration mechanics, Behind-armor fragments

Reactive materials bring the dramatically enhanced lethality by means of the combined defeat mechanisms of impact kinetic energy and chemical energy release. This paper presents such an investigation on these reactive materials for the enhanced initiation behavior of covered explosives. First, a simple initiation process comparison between the inert metal and reactive material projectiles impacting covered explosives is described. Then high velocity ballistic impact experiments, which include both reactive material and tungsten alloy projectiles with mass matched against covered explosives, are conducted to investigate and compare the initiation behavior of covered explosives. Finally, theoretical analysis and discussions about contributions of both kinetic energy-to-initiation and chemical energy-to-initiation mechanisms to the enhanced initiation behavior of covered explosives impacted by reactive materials are presented.

Damage effects of the double-spaced aluminum plates, impacted by the cold isostatically pressed and sintered PTFE/Al/W reactive material projectile with a density of 7.8 g/cm 3 , were investigated by the ballistic impact experiments and the theoretical analyses. Three kinds of the double-spaced plates with the thicknesses of 3 mm/3 mm, 6 mm/3 mm and 6 mm/6 mm were used. The distance between the front and the rear plate was 200 mm. The cylindrical reactive projectile with the mass of 8 g was launched at the velocities of approximate 710 m/s∼950 m/s to impact the target. It has been shown that the plugging damage pattern is formed on the front plate impacted by the reactive projectile. Moreover, damage to the rear plate is significantly influenced by the impact velocity and the front/ rear plate thickness. For mechanism consideration, the plugging damage to the front plate is caused by the kinetic energy impact of the reactive projectile. However, damage to the rear plate is caused by the kinetic energy impact of residual projectile and fragment cloud. The chemical release may also enhance the damage to the rear plate.

Background Recurrence of hand, foot and mouth disease (HFMD) pandemics continues to threaten public health. Despite increasing awareness and efforts, effective vaccine and drug treatment have yet to be available. Probiotics have gained recognition in the field of healthcare worldwide, and have been extensively prescribed to babies and young children to relieve gastrointestinal (GI) disturbances and diseases, associated or not with microbial infections. Since the faecal-oral axis represents the major route of HFMD transmission, transient persistence of probiotic bacteria in the GI tract may confer some protection against HFMD and limit transmission among children. Methods In this work, the antiviral activity of two commercially available probiotics, namely Lactobacillus reuteri Protectis (L. reuteri Protectis) and Lactobacillus casei Shirota (L. casei Shirota), was assayed against Coxsackieviruses and Enterovirus 71 (EV71), the main agents responsible for HFMD. In vitro infection set-ups using human skeletal muscle and colon cell lines were designed to assess the antiviral effect of the probiotic bacteria during entry and post-entry steps of the infection cycle. Results Our findings indicate that L. reuteri Protectis displays a significant dose-dependent antiviral activity against Coxsackievirus type A (CA) strain 6 (CA6), CA16 and EV71, but not against Coxsackievirus type B strain 2. Our data support that the antiviral effect is likely achieved through direct physical interaction between bacteria and virus particles, which impairs virus entry into its mammalian host cell. In contrast, no significant antiviral effect was observed with L. casei Shirota. Conclusions Should the antiviral activity of L. reuteri Protectis observed in vitro be translated in vivo, such probiotics-based therapeutic approach may have the potential to address the urgent need for a safe and effective means to protect against HFMD and limit its transmission among children.