Trend analysis of rainfall and streamflow in "Alto Teles Pires Watershed", northern Brazil.

In this studied were analyzed the streamflow and rainfall of the "Alto Teles Pires Watershed", northern Brazil, in the period from 1977 to 2009.H11G-0934

Technology and Methodology for the Production of High Quality Polymer Filler and Super-Pozzolan from Fly Ash

A novel method for producing fly ash material with a range of particle sizes from about 2.0 to about 4.0 μm is provided utilizing superplasticizers. The method produces fly ash material suitable for use as filler material in the plastics industry and super pozzolan for the concrete industry

Froth Flotation Method for Recovery of Ultra-Fine Constituent

A froth flotation method and apparatus for the recovery of ultra-fine constituent are provided. The apparatus includes a flotation column having a drain for withdrawing tailings and underflow and an overflow for recovering the selected ultra-fine constituent. A mechanism is provided for delivering a wash medium to an upper portion of the column as well as for delivering diffuse air to a lower portion of the column. A slurry including the constituent to be recovered is received and conditioned within a tank that is connected by means of a feed line to the column. Additionally, a mechanism is provided for dissolving air in the slurry in the conditioning tank. Further, one or two matrixes may be mounted across the flotation column to further improve recovery. The method broadly includes the steps of (1) dissolving air in the slurry in the conditioning tank; (2) feeding the slurry through the feed line into an intermediate portion of the flotation column; (3) adding a reagent to the slurry that renders the selected constituent hydrophobic; (4) establishing and maintaining a downwardly flowing stream of wash medium in the flotation column; (5) establishing and maintaining an upwardly moving stream of diffuse air originating at a lower portion of the flotation column; and (6) recovering the selected ultra-fine constituent and diffuse air from the upper portion of the column

Rare Earth-Bearing Particles in Fly Ash Carbons: Examples from the Combustion of Eastern Kentucky Coals

Graphitic carbons from the combustion of bituminous coals and, perhaps, other coal ranks, tend to capture iron and a number of hazardous elements, including As, Hg, and Se. Rare earth elements in fly ashes occur in minerals, such as monazite, xenotime, and davidite. They also occur in sub-nm particles, probably in a mineral form, within the Al–Si glass on the investigated fly ashes. Just as graphitic carbons can capture Fe and hazardous elements, the carbons surrounding the fly ash glass and magnetic particles captures or encapsulates a broad suite of rare earth elements

Do crowdfunding returns reward risk? Evidences from clean-tech projects

The growing literature on crowdfunding has mostly focused on the determinants of campaigns success, as well as on the legal and macroeconomic drivers of the crowdfunding diffusion as a mean to finance innovative projects. Still there are scant evidences on whether the returns for crowdfunders are consistent with the risk profile of crowdfunded projects. By studying 365 European clean-tech projects which raised capital via crowdfunding, we show that once the country risk has been accounted for, the returns are not consistent with the risks related to the technology adopted by the projects. Behavioral factors like bounded rationality or the cultural dimension of investors may explain this apparent mispricing of risks. While projects' returns are, on average, negatively related to risks, we find that projects offering better risk-adjusted returns attract relatively larger average contributions. Our results have important implications for understanding the drivers of crowdfunding returns and its sustainability, and particularly for its diffusion as an instrument to foster the transition to a low-carbon economy.info:eu-repo/semantics/acceptedVersio

Method for Improving the Pozzolanic Character of Fly Ash

A method for improving the pozzolanic character of fly ash includes the steps of first hydraulically classifying and then flotation separating the fly ash in order to reduce particle size distribution and remove carbon. The method also includes the steps of spiral concentrating separated coarse particles to recover iron, pyrite and marcasite and screening the fly ash to remove ultra-light carbon and plant debris