Improvement of Bond Strength and Durability of Recycled Aggregate Concrete Incorporating High Volume Blast Furnace Slag.

This paper aims to experimentally investigate the effects of high volume cement replacement of blast furnace slag (BFS) on the bond, strength and durability of recycled aggregate concrete (RAC). Concrete mixtures were prepared containing 0%, 15%, 30%, 45%, 60% and 75% BFS with each of recycled aggregate and natural aggregate. Measurements of the compressive and bond strength, the resistance to chloride-ion penetration and the water permeability of concrete are reported. In addition, a microhardness test was also performed to evaluate the quality of interfacial transition zone (ITZ) in concrete. Test results of the bond strength and the compressive strength of RAC mixtures, in spite of the cement replacement amount with BFS, show that the concretes result in reduced strength when compared to natural aggregate concrete (NAC) mixtures, while the strength gains for the BFS-based concrete are higher than that of the reference mixtures without BFS at long-term ages. Incorporating BFS in concrete can inherently improve the durability properties by increasing higher resistance to chloride-ion penetration and lower water permeability. This improvement in the mechanical and durability properties of the BFS-based RAC mixture may be due to the additional pozzolanic reaction of BFS, which enhances the properties of ITZ in concrete, resulting in an improvement of the strength of concrete.

Recycling furnace slag and fly ash from industrial byproducts to produce slag/ash based zeolite as a new adsorbent material.

This study recycling the industrial byproducts of furnace slag and fly ash to produce slag/ash based zeolite. A scanning electron microscopic/energy dispersive X-ray spectroscopic (SEM/EDS) analysis of this zeolite indicates a high SiO2 content of 53.94%, an Al2O3 content of 23.20%, a silicon-to-aluminum ratio of 2.049, a density of 2.88 g/cm3, and a water content of 0.13% while the zeolite appears as a porous crystalline structure. Results of weighing experiments revealed effective adsorption of liquid salad oil and highly volatile organic solvents after reusing the zeolite up to 6 times. When an adsorbed liquid pollutant was desorbed and the heating temperature exceeded 170 °C and 350 °C, the samples exhibited two exothermic reactions, respectively, the mean maximum enthalpy were 0.427 and 0.461 mW, and the mean per gram of accumulated heat were 80.92 and 45.64 J/g. For all samples, the mean maximum loss of mass rate was 9.26%. Analogously, for gaseous pollutants, the samples exhibited an exothermic reaction when the heating temperature exceeded 180 °C; the average maximum enthalpy was 0.395 mW, the average per gram of accumulated heat was 119.60 J/g, and the average maximum loss of mass rate was 4.79%. This slag/ash based zeolite has the advantages of low cost, high thermal stability, reusability, etc., and can be used as a new adsorbent material for indoor ventilation equipment.

Analgesic and Anti-Inflammatory Activities of the Ethanolic Extract of Artemisia morrisonensis Hayata in Mice.

The aim of this study was to investigate the possible analgesic and anti-inflammatory mechanisms of the ethanolic extract of A. morrisonensis Hayata (AM(EtOH)). Two models were employed for evaluation of the analgesic effects: acetic acid-induced writhing response and formalin-induced paw licking. The results demonstrated that AM(EtOH) decreased writhing response for both the acetic acid assay and the licking time in the formalin test. The anti-inflammatory effect was evaluated by paw edema of mice induced by λ-carrageenan. AM(EtOH) significantly decreased induced paw edema three to four hours after λ-carrageenan injection. Additionally, the results indicated that the anti-inflammatory mechanism of AM(EtOH) may be due to the declined levels of nitric oxide (NO) and malondialdehyde (MDA) in the edematous paw. Furthermore, AM(EtOH) decreased the tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) levels, leading to the reduction of prostaglandins and subsequently alleviated edema. Isolation and purification of the AM(EtOH) extract determined p-hydroxyacetophenone to be a major component at 130 mg/g of extract. No mortality was observed in the acute toxicity test given at the dose of 10 g/kg. This study demonstrated the possible mechanisms for the analgesic and anti-inflammatory effects of AM(EtOH) for mice and provided evidence for the ethnobotanical uses of A. morrisonensis in treating inflammatory diseases.