Acid bioleaching of a low-grade and polymetallic sulfide concentrate was studied, in order to determine suitable feed material particle size pH for efficient leaching valuable metals. The consisted pyrite (50 wt %), pyrrhotite (31 quartz (10 %) lower amounts cobalt, nickel, zinc copper (each <1 %). After adaptation microorganisms shake flasks, stirred tank tests were conducted at different l...

Due to the importance of material classification issue in grinding circuits, the ‎performance of primary and secondary hydrocyclones in grinding circuit of Esfordi ‎phosphate plant was investigated by sampling within 7 days from feed, overflow, and ‎underflow‎ of these hydrocyclones. At first, the d80 of above streams samples were calculated by ‎the screening analysis. The results showed ‎that ...

We formulate a dynamic framework for an individual decisionmaker within which discovery of previously unconsidered propositions is possible. Using a game-theoretic representation of the state space as a tree structure generated by the actions of agents (including acts of nature), we show how the existence of unconsidered propositions can be represented by a coarsening of the state space. Furthe...

This paper investigates the effect of stock market microstructure on managerial compensation schemes. We propose and empirically demonstrate that the sensitivity of chief executive officer’s (CEO’s) compensations to changes in stockholders’ value is higher when the stock market facilitates the production and aggregation of private or public information. Using stock trading data and analysts’ ea...

We use the venture capital market to examine two phenomena: “grandstanding” by relatively inexperienced venture capital firms and the effect of proximity on soft information production. We show that these phenomena are closely related. Inexperienced VC firms—those with the strongest incentives to grandstand— tend to match with young and small companies within close proximity, presumably to enha...

We develop a model of games with awareness that allows for differential levels of awareness. We show that, for the standard modal logical interpretations of belief and awareness, a player cannot believe there exist propositions of which he is unaware. Nevertheless, we argue that a boundedly rational individual may regard the possibility that there exist propositions of which she is unaware as b...

Neeman (2004) and Heifetz and Neeman (2006) have shown that, in auctions with incomplete information about payoffs, full surplus extraction is only possible if agents’ beliefs about other agents are fully informative about their own payoff parameters. They argue that the set of incomplete-information models satisfying this so-called BDP property ("beliefs determine preferences") is negligible, ...

From the real options perspective the firm is conceived as a portfolio of real options. However, the theory of the firm traditionally argues into a similar direction by viewing the firm as either a set of institutions, as set of property rights or as a set of contracts. Due to this similarity, the question arises how far real options analysis can contribute to the theory of the firm and to an u...

This paper analyzes optimal linear taxes on labor income and savings in a twoperiod life-cycle model with ex ante identical households, endogenous leisure demands in both periods, and general processes of skill shocks over the life cycle. We demonstrate that the Atkinson-Stiglitz theorem breaks down under risk. Capital taxes are employed besides labor income taxes for two distinct reasons: i) c...