Bioleaching of spent catalyst using moderate thermophilic chemolithotrophic acidophiles in growth medium without Fe source was investigated with two different pulp densities and three different size fractions. All the experiments were conducted on shake flasks at a temperature of 65 °C. The leaching yield of Ni and Al was found to be promising with very high leaching yield of 92-96% followed by...

sclerotinia stem rot (ssr), caused by sclerotinia sclerotiorum, is the most important diseases of canola (brassica napus) in iran. in order to study of the impact of ssr on canola yield, infection situation and yield of 80 fields in four different regions of golestan province (gorgan, ali abad, kalaleh and gonbad) in north of iran, was recorded during two growing seasons (2006 and 2007). ssr se...

in order to evaluate the yield and nitrogen use efficiency of corn and cotton intercropping under different levels of nitrogen, an experiment was conducted as a factorial arrangement based on completely randomized block design with three replications. the experimental treatments were nitrogen fertilizers in four levels (0, 50, 100 and 150 kg ha-1) and planting pattern in three levels (maize sol...

BACKGROUND The classical Paal-Knorr reaction is one of the simplest and most economical methods for the synthesis of biologically important and pharmacologically useful pyrrole derivatives. RESULTS Polystyrenesulfonate-catalyzed simple synthesis of substituted pyrroles following Paal-Knorr reaction has been accomplished with an excellent yield in aqueous solution. This method also produces py...

A number n is said to be economical if the prime power factori-sation of n can be written with no more digits than n itself. We show that under a plausible hypothesis, related to the twin prime conjecture, there are arbitrarily long sequences of consecutive economial numbers, and exhibit such a sequence of length 9.

An effective method was developed for the preparation of Brucella abortus native hapten by use of an ultrafiltration system. The membranes PM30 and YM5 were used to separate the lipopolysaccharide and the native hapten. The yield of the native hapten was higher than that obtained by a more complex procedure reported previously. This method is economical for the large-scale preparation of B. abo...

Chemical engineering deals with synthesis of various chemicals in economical and efficient manner. Raw material is important aspect for cost effective manufacturing of chemicals. Biological methods for syntheis consume less energy and are very economical for production of chemicals such as ethanol, acetic acid, citric acid, lactic acid etc. Waste solid materials such as molassis, fruit peels, w...