The impact of cleaner processing on nutrient availability in the bleached kraft industry.

The pulp and paper industry has invested heavily over recent years in cleaner processing, to reduce losses and minimise its impact on the environment. Over the past fifteen years, a New Zealand integrated bleached kraft mill has undergone a comprehensive programme of upgrades to increase production, reduce water consumption and streamline its biological treatment process. Whilst the overall discharge of contaminants from the site decreased, the treatment system performance did not show a concurrent improvement as may have been expected. Reduced BOD removal, low dissolved oxygen levels, and poor solids settlability were symptomatic of phosphorus limitation in the aerated lagoon treatment system. The wastewater entering the system was found to be phosphorus limited at a BOD:P ratio of 100:0.2. Mono-ammonium-phosphate was supplemented, at approximately 30 kg P/d, to raise the phosphorus levels to a BOD:P ratio of 100:0.3. Treatment efficiencies improved very quickly after phosphorus dosage, with a 50% reduction in BOD and TSS discharge, a significant increase in dissolved oxygen levels, and improved BOD removal (85% to 93%). This case study demonstrates that whilst more closed operation can result in reduced discharge of organic loads, there may be negative impacts on the availability of nutrients for balanced biological growth.     

New technological solutions to protect the lining of blast-furnace hearths

The use of schungite as a partial replacement for coke is practiced in Russia at a number of metallurgical plants, both in the production of foundry iron (its primary use) and in making conversion pig iron. The largest amount of coke is replaced when foundry iron is being made, the replacement coefficient in this case having a value within the range 0.8–1.3. Studies that included continuous monitoring of the temperature of the carbon blocks in blast furnaces with volumes of 1719, 3200, and 5580 m³ unambiguously demonstrate that the thickness of the slag crust in blast furnaces increases with the use of schungite. Protecting the lining of the hearth through the use of schungite is also accompanied by a decrease in coke consumption. __________ Translated from Metallurg, No. 8, pp. 53–57, August, 2007.     

Simulation of contact stresses and forces during hot rolling of thin wide strips with allowance for a stick zone and elastic regions in the deformation zone

A new procedure for the calculation of contact stresses and hot-rolling forces for wide strips 0.8–1.5 mm thick has been developed and tested. This procedure takes into account the presence of a stick zone in the deformation zone and stress distributions in both elastic and plastic regions in the deformation zone. The average error in the force calculation according to the new procedure is 5%, which is more than two times smaller than the calculation error of well-known force calculation procedures. The developed procedure is used to simulate the contact stresses in the deformation zones of working stands in a six-stand 1700 mill during rolling of strips thinner than 1.0 mm. A number of new relations for the state of stress in a strip have been revealed upon simulation. Some of these relations are as follows: in the last stands, the length of elastic regions accounts for 10–17% of the total deformation-zone length; the maximum normal contact stresses are 1300–1400 MPa, which corresponds to the stresses in the deformation zones of cold-rolling mills; the stick-zone length accounts for 85–99% of the deformation-zone length; and the contact stresses in the stick zone are virtually independent of the friction coefficient. The developed calculation procedure can be used to optimize the technological regimes of wide-strip mills.     

Life history of Teretriosoma nigrescens Lewis (Coleoptera: Histeridae) and its ability to suppress populations of Prostephanus truncatus (Horn) (Coleoptera: Bostrichidae)

The life history and behaviour of Teretriosoma nigrescens Lewis are typical of a histerid predator, but only 2, instead of the expected 3, larval instars were recorded. At 27°C, 70% r.h. development from oviposition to adult emergence took about 8 weeks. In 24 h at 27°C, 70% r.h., T. nigrescens adults and larvae, respectively, consumed on average up to 1.7 and 3.5 Prostephanus truncatus (Horn) larvae. After 7 weeks, 10 T. nigrescens adults prevented populations of 25, 50, 75 and 100 P. truncatus from increasing, while controls increased at least 10-fold. Grain moisture contents of between 8.5–14% had little effect on predatory efficiency.     

Boys and violence: A gender-informed analysis.

This article discusses the phenomenon of youth violence from a psychology of gender perspective. Although other factors are discussed--including gun availability, violence-related media influence, family and caretaker factors, and effects of teasing and bullying--the intention is to highlight new thinking on the potential relationship between boys' traditional masculine socialization experiences and violence. In this new perspective, traditional masculine socialization estranges and isolates many boys from their genuine inner lives and vital connections to others, which is theorized to heighten their risk of engaging in acts of violence. The authors identify school and community programs that may be helpful in counteracting damaging socialization experiences and supporting boys' healthier emotional and psychological development. Finally, the article discusses approaches that psychologists and other mental health professionals can use to help address this vital issue. (PsycINFO Database Record (c) 2010 APA, all rights reserved)