Terms Of Dry Matter Content Research Articles

Chemical Characterisation of Organic Electron Donors For Sulfate Reduction For Potential Use in Acid Mine Drainage Treatment

The production of acid mine drainage (AMD) containing high amounts of sulfate, heavy metals and low pH is of increasing concern. AMD is highly corrosive and results in economic and environmental problems. Organic electron donors for sulfate reduction were chemically characterised for potential use in AMD treatment. This was done in a process to develop a correlation between chemical composition and the capacity to drive sulfate reduction. Potential organic electron donors for sulfate reduction were chemically characterised in terms of dry matter content, ash content, total Kjeldahl nitrogen, lignin content, cellulose content, crude fat, crude fibre, in vitro digestibility, water-soluble carbohydrates, total non-structural carbohydrates and starch content. The chemical composition of the organic electron donors was then compared to results obtained from pilot plant studies where the organic electron donors for sulfate reduction were evaluated in terms of sulfate reduction. The chemical composition of the carbon source severely impacted its capacity to drive sulfate reduction and may be used to assist in predicting the sulfate reduction capacity of a carbon source. Organic electron donors for sulfate reduction high in protein content and low in lignin content or high in carbohydrate and crude fat content increased the capacity of a carbon source to drive sulfate reduction. The higher the fibre content of a carbon source, the lower the capacity to drive sulfate reduction. No correlation could be drawn between % dry matter, % ash content and sulfate reduction for the organic electron donors tested. Chemical characterisation can be used to assist in predicting sulfate reduction capacity of organic electron donors.

SW—Soil and Water: Lignin-based Interpolymer Complexes as a Novel Adhesive for Protection against Erosion of Sandy Soil

New amino-containing soil conditioners based on lignosulphonate (LS), a by-product of the papermaking industry, have been developed to create an artificial soil macrostructure and to reinforce surface layers, withstanding wind and water erosion on light sandy soil.The conditioners created are interpolymer complexes (IPCs) formed by an intermolecular reaction between LS and polymer or oligomer amines in aqueous medium. Owing to a pronounced gluing ability, IPCs are capable of reinforcing the surface layers of sandy soil with a thickness of 1·2–10·2 mm and a penetration resistance of 0·16–0·98 MPa at application rates of 0·045–0·320 kg m−2in terms of dry matter content. It has been established that the surface layers formed by applying an IPC containing oligomer amine are characterized by worse mechanical properties and stability against erosion in comparison to those formed with the IPC containing polymer amine. The introduction of polyvalent metal salts, such as FeCl3and Cu(NO3)2, into the IPC results in the formation of triple polymer–metal complexes, whose structuring and stabilizing action on sandy soil is more pronounced than for double IPCs. This reveals itself in a decrease in soil losses by 20–25% at a wind speed of 25 m s−1, a drop in soil losses of 30–35% and a reduction in the water surface runoff by 40–45% under the simulation of water erosion conditions.The layers formed by the application of both double and triple IPCs are photoresistant owing to the peculiarities of the chemical structure and composition of these glues.Clover seeds easily germinate through the air-dry-reinforced surface layers formed at an application rate of no more than 338 kg m−2in terms of dry matter content.

Relationship of Maternal Dietary Zinc during Gestation and Lactation to Development and Zinc, Iron and Copper Content of the Postnatal Rat

High levels (0.2 and 0.5%) of zinc were fed to adult female rats beginning at zero-day age of the fetus and continued to day 14 of lactation to study the development and iron, copper, and zinc status of zero- and 14-day-old postnatal rats. The results were compared with rats fed a basal diet containing 9 ppm zinc. Growth reduction, in terms of dry matter content, was characteristic of the zero- and 14-day-old young from mothers fed 0.5% zinc. Though no anatomical malformations were observed, the incidence of stillbirths was high in the 0.5% zinc group. Young from mothers fed 0.2% zinc were larger in body size than those from mothers fed the basal diet. Total zinc and concentration of zinc were elevated in zero- and 14-day-old young by both high zinc diets. Young from mothers fed 0.5% zinc contained higher levels of zinc than those from mothers fed 0.2% zinc. Bodies of newborn young from mothers fed 0.5% zinc contained significantly less total iron and concentration of iron, whereas the liver contained significantly more iron. At 14 days of age the whole animal and body of young from mothers fed 0.5% zinc contained significantly less total iron and concentration of iron. Liver iron in these young was lower than found in the liver of newborn, and total iron and concentration of iron in the liver were similar for all groups. Total copper and concentration of copper in the whole animal and body of the newborn rats were not altered due to treatment. Total copper and concentration of copper in the liver were significantly lower only in the newborn from mothers fed 0.5% zinc. After 14 days, total copper and concentration of copper were significantly lower in the whole animal, liver and body of young from mothers fed either zinc diet than in young from mothers fed the basal diet. In general, a larger reduction in copper occurred in the young from the 0.5% zinc treatment. Mothers fed 0.2% zinc gained more weight during gestation. Dietary treatments had no effect on body weights during lactation. Livers of maternal animals fed excess zinc contained elevated zinc, and reductions in both iron and copper.