Development and Characterization of Norite-Based Cementitious Binder from an Ilmenite Mine Waste Stream

This is an open access article distributed under the Creative Commons Attribution License, originally published in Advances in Materials Science and Engineering.Norite is a major type of solid waste generated during the production of ilmenite. This study focuses on the usability of norite as a solid precursor of alkali-activated cement. Sensitivity analysis was performed to find the influence of different alkali types and particle sizes of the source material on polycondensation. Norite was ground and mixed with sodium hydroxide and potassium hydroxide solutions to produce a binder. Potassium-containing systems were more effective compared to sodium-containing systems with respect to strength development. The X-ray diffraction patterns indicated formation of zeolites, albite, and oligoclase based on the type of activator and used additives. The patterns also revealed formation of an amorphous phase in the matrices of the binder that was cured at 87°C. Microstructure analysis revealed some degree of crystallization with different Si : Al ratios, which indicated heterogeneity of the binder matrices.publishedVersio

Impact of organic agriculture on diversity and abundance of farmland birds in an arable landscape with hedges

A comparative study of breeding bird communities of organically and conventionally cultivated arable fields was carried out in northern Germany in 2005. The research was conducted on 40 pairs of fields (conventional/organic), which were selected with regard to similar field sizes and comparable boundary structures (particularly presence of hedges). Bird communities were solely dominated by the skylark Alauda arvensis L., which was the only frequent species on the tested pairs of fields. Diversity of farmland birds (number of species, Shannon-Index) was not affected by type of management. However, the abundance of skylarks (territories/10 ha) was significantly higher in organic than in conventional fields. As the study will be continued, the one-year findings will be verified with respect to changes of crops in rotations