Improving the adsorption capacity and solid structure of natural volcanic soil using a foaming-sintering process based on recycled polyethylene terephthalate (PET).

The volcanic soils of southern Chile have demonstrated a high capacity to adsorb environmental pollutants, but for an industrial application, a stable solid material is necessary. The objective of this work was to produce a stable ceramic material through a process involving volcanic soil-polyurethane foam produced with recycled polyethylene terephthalate (PET)-polyols, and further thermal treatment. The selected foam formulation with 35.4% volcanic soil (< 63 microm) seems to be the most suitable for thermal treatment, with temperature steps at 700, 850, 1000 and 1200 degrees C. The porous ceramic material obtained has a stable solid form and an improved chlorophenols adsorption capacity (comparable to natural zeolites) that makes it suitable for advanced wastewater treatment and landfill leachate depuration.     

Cnidosac morphology in dendronotacean and aeolidacean nudibranch molluscs: from expulsion of nematocysts to use in defense?

Nudibranchs (Mollusca, Gastropoda) feeding on tentacles and polyps of Cnidaria thereby ingest both latent and discharged nematocysts (NCs) along with the food mass. In eolid nudibranchs (Opisthobranchia, Aeolidacea), many of the undischarged NCs are transported to terminal cnidosacs in their body appendages (cerata) and incorporated as kleptocnidae for defense. In the present report, the occurrence and fate of NCs in the digestive tracts of eolids is compared with hydrozoan-feeding dendronotacean nudibranchs (Opisthobranchia, Dendronotacea), which may show more basic stages in the evolution of cnidosacs. Tomographic reconstructions of the distal tips of cerata were composed from series of semithin light microscopic sections, utilizing 3D-surface rendering software. Doto acuta (Dendronotacea, Dotidae) does not have cnidosacs; transmission electron micrographs show that the NCs are digested in lysosomes of digestive gland cells. In contrast, species of the genus Hancockia (Dendronotacea, Hancockiidae) have several small cnidosacs in each ceras; they accumulate NCs in the digestive cells, as well as in the cnidosacs. Many of the cnidosacs were found open to the exterior with NCs in the process of expulsion. These and other structural details suggest assigning a function of expelling the NCs to the Hancockia spp. cnidosacs. It is proposed that cnidosacs similar to those of Hancockia spp. provide a clue to understanding how the defensive function of eolid cnidosacs may have evolved. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Der Einfluß von Aureomycin und Tween 60 sowie der Vitamine A,E und B12 auf den Nukleinsäurestoffwechsel der Ratte

The Science of Nature -     

Exploring potential socio-ecological impacts of changes to the Loliondo Gamed Controlled Area,Northern Tanzania: the case of the pastoral village Ololosokwan

Recent plans to alter the Loliondo Game Controlled Area (GCA), a nature conservation area located in Northern Tanzania, would result in substantial reduction of rangelands in the region. We quantify the current and hypothetical levels of the aboveground Human Appropriation of Net Primary Production (aHANPP) in one of the affected villages, and estimate the maximum exploitability rate of rangelands by livestock in the region. We find that the current aHANPP of the village amounts to 34–38% of the potential productivity, which could increase to 59–67% due to the altered GCA. On rangelands, livestock-induced aHANPP would increase from the current level of 30–34% to 54–61%, which is far above a maximum exploitability rate of 40–41%. Our results reveal that the intended changes to the Loliondo GCA will severely affect the current livelihood strategy of the Maasai, which is based on pastoralism.     

Ozone fumigation (twice ambient) reduces leaf infestation following natural and artificial inoculation by the endophytic fungus Apiognomonia errabunda of adult European beech trees

In 2006, a controlled infection study was performed in the ‘Kranzberger Forst’ to address the following questions: (1) Will massive artificial inoculation with Apiognomonia errabunda override the previously observed inhibitory effect of chronic ozone? (2) Can biochemical or molecular markers be detected to account for the action of ozone? To this end six adult beech trees were chosen, three ozone fumigated (2× ozone) and three control trees (ambient = 1× ozone). Spore-sprayed branches of sun and shade crown positions of each of the trees, and uninoculated control branches, were enclosed in 100-L plastic bags for one night to facilitate infection initiation. Samples were taken within a five-week period after inoculation. A. errabunda infestation levels quantified by real-time PCR increased in leaves that were not fumigated with additional ozone. Cell wall components and ACC (ethylene precursor 1-amino cyclopropane-1-carboxylic acid) increased upon ozone fumigation and may in part lead to the repression of fungal infection.     

Novel process concept for the production of H2 and H2SO4 by SO2-depolarized electrolysis

Outotec open cycle (OOC) is a new low-energy process linking together production of hydrogen and sulfuric acid. While sulfuric acid is the world’s most widely produced chemical by mass at approximately 200 Mt/a, the OOC gives the potential for making 4 Mt/a of hydrogen gas as a by-product. H₂SO₄ manufacture requires a source of sulfur dioxide. 30% of world production of H₂SO₄ is from the SO₂ by-product of pyrometallurgical processing of sulfur containing concentrates of metals such as copper, nickel and zinc. SO₂ can also be made by direct combustion of sulfur. In OOC, a divided electrochemical cell is used for SO₂-depolarized electrolysis of water. SO₂ is fed to the anolyte and converted to H₂SO₄, while hydrogen gas is produced at the cathode. On the industrial scale, the equipment will be in the form of a membrane electrolyzer assembly or stack. A case is described where the OOC would be connected to a pyrometallurgical plant smelting 1 Mt/a of nickel and copper concentrate, producing 1 Mt/a of H₂SO₄ and 20 kt/a of hydrogen.