New possibilities of chemical beneficiation of synnirites

Institute of Geology Siberian Branch, Academy of Sciences of the USSR, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 1, pp. 106–109, January-February, 1992.     

Fast Simulation of the Functional Failure of an s – t-Network with Repair

An s – t-network with highly reliable edges with repair and variable external load is considered. A fast simulation method is proposed to evaluate the probability of functional failure when the real capacity of the network is less than the required capacity. It is proved that under some conditions the estimate has a bounded relative error as edges reliability increases. The numerical example illustrates the efficiency of the method.     

Evaluation of Steady State Probabilities of the • / <Emphasis Type="Italic">G</Emphasis> / ∞ Queuing System for Different Input Flow Models

Five input flow models are considered whose structures are considerably more complicated than a Poisson structure and in which steady state probabilities of the ?/ G / ∞ queuing system can be found in explicit form (the Poisson distribution). For these models, a combination of the Poisson distribution (the analytical part) and statistical simulation (the statistical part) allows one to evaluate steady state probabilities by accelerated simulation. The accuracy of the obtained estimates is illustrated by numerical examples.     

Stagewise Disintegration and Mechanical Activation in Dressing of Tin-Bearing Waste

Journal of Mining Science - The authors test grinding of mining waste material to a preset grain size composition under stagewise increased destructive force and at reduced sliming. The optimized...     

A new approach to the production of aluminum and its compounds from nonconventional alumina feedstock

The paper describes a new approach to alumina and aluminum production from a nonconventional aluminosilicate feed, namely, zeolite tuffs. The authors substantiate mineralogical features and technological principles of treatment of zeolites and clayey minerals that are in composition of zeolite ores. The illustrated use perspectiveness for the zeolite processing and mechanical activation will greatly enhance the processes of opening and decomposition of base minerals. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 2, pp. 96–101, March–April, 2009.     

Influence of electrodeposition parameters on structural and morphological features of Ni nanotubes

Nickel nanotubes have been formed in pores of ion-track membranes using electrochemical deposition. Morphologic and structural features of these nanostructures have been comprehensively studied. The evolution of the nanotubes wall thickness and parameters of their crystalline structure by variations of the synthesis voltage and temperature has been determined. On the base of these data the nanotubes growth mechanism has been estimated.     

State and perspectives of natural zeolite beneficiation

The efficiency is studied and evaluation is made of the principal methods of concentration of zeolite raw materials, the essential features of which consist in the use of difference in the structure, particle size, density, and magnetic susceptibility of the minerals. A scheme is proposed for magnetic-gravity concentration of zeolites of the Shivyrtuisk deposit. United Institute for Geology, Geophysics, and Mineralogy, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 3, pp. 115–120, May–June, 2000.     

Evaluating Unavailability of a Repairable System Consisting of Components with Significantly Different Reliabilities

A new fast simulation method is proposed for evaluation of unavailability of a repairable system. Its idea is to order failure trajectories according to their ranks that promotes rational experiment organization. The estimates are unbiased and possess a bounded coefficient of variation. A numerical example is considered.