Recent developments in Slag-fuming process

IN most lead -zinc run-of-mine ores, the main valua- ble minerals are galena and sphalerite . Two products, namely a lead concentrate and a zinc concentrate are obtained by the differential froth flotation process. The separation is never complete : the lead concentrates contain a certain percentage of zinc and the zinc concentrates contain some lead. The indigenous source of lead-zinc ore is the Zawar Mines situated at a distance of about 50 km from Udaipur, Rajasthan. Zawar Mines are located in one of the oldest lead, zinc and silver zones of the world. The underground working is at present being carried out in the Mochia Mogra and Balaria Hills area of the mines . The lead concentrates and zinc concentrates are produced by the differential froth flotationprocess. The lead concen- trate contains 72--75 per cent lead, 5 ' 3 per cent zinc and 22 oz/ton of silver. The zinc concentrate contains about 55 per cent zinc, 1 per cent lead and 5 oz ton of silver

Redundant Wavelet Watermarking using Spread Spectrum Modulation

Spread Spectrum modulation has become a preferred paradigm in many watermarking applications. This paper analyzes the performance of such a blind watermarking scheme under discrete wavelet frame rather than a traditional orthonormal wavelet expansion. The over complete representation offered by the redundant frame facilitates the identification of significant image features via a simple correlation operation across scales. The performance and resiliency of the proposed technique are analyzed against several volumetric distortion sources. The experimental results of this oblivious algorithm illustrate better visual and statistical imperceptibility and robustness compared to the usually critically sampled discrete wavelet transform. This algorithmic architecture utilizes the existing allocated bandwidth in the data transmission channel in a more efficient manner

Broad-tailed force distributions and velocity ordering in a heterogeneous membrane model for collective cell migration

Correlated velocity patterns and associated large length-scale transmission of traction forces have been observed in collective live cell migration as a response to a "wound". We argue that a simple physical model of a force-driven heterogeneous elastic membrane sliding over a viscous substrate can qualitatively explain a few experimentally observed facts: (i) the growth of velocity ordering which spreads from the wound boundary to the interior, (ii) the exponential tails of the traction force distributions, and (iii) the swirling pattern of velocities in the interior of the tissue.Comment: 7 pages and 5 figure

Advanced gravity separators - A review of state of the art technology

A comprehensive review of various types of industrial advanced gravity separators (AGS) is presented. The discussion focuses mainly on enhanced gravity separators and teetered bed separators. Enhancement of settling velocity of fine and ultrafines particles is discussed. The principle of separation, application and its separation performance of each device are reviewed. Details of the variables involved and the respective advantages and disadvantages of the separators, along with explanatory diagrams illustrating the processes have been discussed