Truck and shovel operations comprise approximately 60% of the total operating costs in open pit mines. In order to increase productivity and reduce the cost of mining operations, it is essential to manage the equipment used with high efficiency. In this work, the chance-constrained goal programing (CCGP) model presented by Michalakopoulos and Panagiotou is developed to determine an optimal truc...

Anthropogenic activities have caused important increases in soil Cu levels not only in urban areas but also in croplands. This study was designed to find out the effect of different concentration of copper on physiological and biochemical changes in Eucalyptus camaldulensis seedlings. Seeds of Eucalyptus camaldulensis were grown in marble chips and irrigated with nutrient solution mixed with co...

Laccases are multicopper oxidases and play an important role in delignification, sporulation, pigment production, plant pathogenesis and metal detoxification. In the present study, partial laccase gene from ectomycorrhizal fungus H. cylindrosporum was cloned and sequenced. Deduced amino acid sequence of H. cylindrosporum showed similarity to copper binding region I and II domains at N-termini o...

Most of the work which has been done on trace elements in soils has been in relation to deficiency or toxicity effects on plants. Although a certain amount of work has been reported on the effects of trace elements on ammonification and nitrification in soils 12 a 4 5 6 the results obtained are conflicting. Trace elements may be introduced into soil where pesticide sprays e.g. copper fungicides...

The efficacy for phytoremediation of five willow species was tested by experimental copper and cadmium uptake in a greenhouse hydroponic system. Five treatments included two concentrations (5 and 25 microM for each metal) and a control. Metal concentrations in solution as well as solution uptake were monitored. Metal resistance was assessed through effects on the dry weight of roots and shoots....

Heap bioleaching processes are of increasing interest in the mining industry to recover metals from secondary ores. Recently, it has been proposed to use feedback control to improve the rate of mineral extraction. In this paper we compare two feedback approaches, namely Model Predictive Control (MPC) and Extremum Seeking Control (ESC), to improve copper extraction in a heap bioleaching process....

Mixed-microbial assemblages enriched from a septic tank, coastal sediment samples, the digester sludge of a brewery wastewater treatment plant and acidic sulfate soil samples were compared on the basis of growth rate, waste and sulfate reduction rate under sulfate reducing conditions at 30 degrees C. The specific growth rate of various cultures was in the range 0.0013-0.0022 hr(-1). Estimates o...

CODELCO’s Chuquicamata Copper Smelter, located in Chile, must meet an environmental standard established in 2002 that limits the sulfur emissions from the copper-production process. This regulation placed new restrictions on the production process, and consequently the heuristic criteria based on years of operator experience no longer resulted in high production levels. We developed a model to ...

In pilot-plant tests, the linolenate content of soybean oil was reduced to less than 1% without increasing the saturates, by hydrogenation to an IV of about 115 with an active copper-chromite catalyst. The linolenate-linoleate selectivity ratio (KLe/KLo ) was from 9 to 12. Several commercial copper-chromite catalysts were used in hydrogenation tests. The activities of four of five commercial ca...

The enzymatic degradation of recalcitrant plant biomass is one of the key industrial challenges of the 21st century. Accordingly, there is a continuing drive to discover new routes to promote polysaccharide degradation. Perhaps the most promising approach involves the application of "cellulase-enhancing factors," such as those from the glycoside hydrolase (CAZy) GH61 family. Here we show that G...