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See how the world voted! View the top 100 moments in history.
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President Obama recently announced plans to scrap NASA’s Constellation moon-landing project and to redirect funding toward programs that will lay the groundwork for a 2030 Mars expedition. This month JOM asks, what is the impact of the new priorities for NASA?
• The United States will lose its status as a worldwide leader of human spaceflight
• Scientific advancement will be stalled as R&D funding is redirected
• Commercial space launch services will be stimulated to fill the void left by NASA’s new priorities
• The U.S. space program will ultimately be better positioned for deep space exploration
The poll is conducted via the JOM Reader Zone of the TMS Discussion Board. |
| SAMPLE JOM |
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JOM JULY 2004
VOLUME 56, NO.7
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Published monthly by The Minerals, Metals & Materials Society for its members, JOM is a technical journal devoted to exploring the many aspects of materials science and engineering.
Copper, Nickel, and Cobalt Production: Impurity Control and Removal
[p. 29
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Author(s): V. Ramachandran
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An ongoing challenge in the smelting and refining of copper, nickel, and cobalt has been to produce high-purity metals from a diverse range of concentrates containing various impurities at different concentration levels. This commentary discusses four articles that follow on removing impurities in the production of electrolytic copper.
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The Purification of Copper Refinery Electrolyte
[p. 30
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Author(s): James E. Hoffmann
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The phrase "purification of copper refinery electrolyte" is misleading since typically, impurities are controlled by withdrawing a bleedstream of the circulating electrolyte. However, solvent extraction and ion exchange have also found some application in impurity control. This article describes conventional practice, including treatment of the bleedstream, and other attempts at electrolyte purification. Impurities to be discussed include Sb, Bi, As, Ni, Ca, ammonia, and organic fragments generated from hydrolysis of conventional cathode growth-modifying addition agents
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Impurity Control and Removal in Copper Tankhouse Operations
[p. 34
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Author(s): Shijie Wang
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During copper smelting, most of the undesirable impurities such as Pb, Sb, Bi, and As are only partially removed by oxidation. When white metal and blister copper are in equilibrium, these impurities are distributed mainly into the copper phase, from which their removal is difficult. When copper dissolves during electrorefining in a copper tankhouse, these impurities are continuously released from the anodes either as insoluble phases (slimes), which fall to the bottom of the cell, or as dissolved species in the electrolyte, the transfer of which to the cathode must be inhibited. This article presents impurity control methods in copper tankhouse operations with traditional and newly developed processes. It also summarizes the technologies demonstrated for removal of impurities from electrolyte that prevent them from being recycled in the copper smelting and refining circuit.
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The Commercialization of the FENIX Iron Control System for Purifying Copper Electrowinning Electrolytes
[p. 38
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Author(s): D.R. Shaw, D.B. Dreisinger, T. Lancaster, G.D. Richmond, and M. Tomlinson
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The FENIX Hydromet Iron Control System was installed at Western Metals Copper Ltd.'s Mt. Gordon Operations in Queensland, Australia. The system uses a novel and patented ion-exchange resin to selectively remove iron from copper electrolyte at the solvent extraction/electrowinning plant. At Mt. Gordon, the system delivered significant savings in reagent consumption (acid and cobalt sulfate for electrowinning and lime for neutralization of the raffinate bleed) and has the potential to deliver higher current efficiencies in copper electrowinning, leading to increased copper production.
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Using Carbonate Fluxes to Remove Oxygen and Sulfur from Blister Copper
[p. 42
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Author(s): P. Coursol and P. Larouche
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A new method for simultaneously removing oxygen and sulfur from blister copper by adding sodium carbonate is described in this article. The main factors influencing the thermodynamics of the reaction, such as temperature, composition of the blister copper, and carbonate/sulfate salt ratio are presented with the help of phase diagrams. The results of preliminary experiments are very encouraging as copper containing 2–145 ppm sulfur and 1,100–3,700 ppm oxygen was produced without the use of a conventional hydrocarbon-reduction stage.
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GOLD PROCESS MINERALOGY PART I
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The Process Mineralogy of Gold: The Classification of Ore Types
[p. 46
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Author(s): J.P. Vaughan
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The principal gold minerals that affect the processing of gold ores are native gold, electrum, Au-Ag tellurides, aurostibite, maldonite, and auricupride. In addition, submicroscopic (solid solution) gold, principally in arsenopyrite and pyrite, is also important. The main causes of refractory gold ores are submicroscopic gold, the Au-Ag tellurides, and very fine-grained gold (<10 μm) locked in sulfides. Other types of problem gold ores include copper-gold ores and preg-robbing carbonaceous ores.
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Gold Process Mineralogy: Objectives, Techniques, and Applications
[p. 49
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Author(s): Joe Y. Zhou and Louis J. Cabri
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The extractive metallurgy of gold is largely driven by mineralogical factors such as gold particle size; association with other minerals; coatings; presence of cyanicides, oxygen consumers, and preg-robbers; presence of refractory gold minerals; and locking of submicroscopic gold in sulfide and sulfarsenide mineral structures. Gold process mineralogy addresses all issues related to gold ore processing by the detailed study of an ore or a mill product. The methodology is widely used as a predictive tool in feasibility studies and during the process development stage, and as a trouble-shooting tool for mineral processing and hydrometallurgical operations.
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Diagnostic Microbeam Technology in Gold Ore Processing
[p. 53
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Author(s): Stephen Chryssoulis, Robert Dunne, and Andre Coetzee
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This treatise offers a brief but comprehensive glimpse of how microbeam analytical techniques have been applied over the last 20 years to resolve problems in gold ore processing. It covers only those techniques that are being used on a routine basis to study gold occurrences in plant samples. To facilitate the readers' understanding, the microbeam techniques are introduced (and assessed) from a problem-solving point of view. These microbeam techniques form an intricate part of the comprehensive mineralogical and analytical approach used to establish on a direct and quantitative basis the occurrence of gold in tailings. Gold deportments determined by microbeam analytical techniques will identify opportunities for optimization and provide realistic targets for reducing the gold content in tailings streams. This approach has been applied in a number of gold operations, with the ultimate benefit of improved gold recovery.
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Flaky Gold: Problems with Recovery and Mineralogical Quantification
[p. 58
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Author(s): Stephen W. Knipe, Stephen L. Chryssoulis, and Bruce Clements
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Mineralogical studies have consistently revealed that flaky gold is common in the tailings from both gravity and flotation circuits, where it can be a significant contributor to losses. A combination of case study and laboratory data has been used to illustrate the extent and causes for problems associated with flaky gold. An additional problem is encountered when trying to quantify gold grades based on microscopy area measurements. An alternative methodology has been developed using a micro-weighing technique that has also been used to produce empirical correction factors for the microscopy-derived gold grades.
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Things that Go Boom in the Night: The Art and Science of Fireworks
[p. 12
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Author(s): Kelly Roncone
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The brilliant displays of fireworks that are used around the world are, at their core, a basic reaction between metals and oxidizers. This article reveals the work that goes on on the ground to prepare for spectacular explosions in the sky.
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And So it Begins: Introducing the JOM World Nonferrous Smelters Survey
[p. 20
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Author(s): Thomas P. Battle
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Included in this issue of JOM is the first installment in an ambitious new TMS program, the World Nonferrous Smelters Survey. This program is being led by volunteers from the TMS Pyrometallurgy Committee who decided to develop a database of all known non-ferrous smelters. The volunteers hope to publish information on one commodity every few months from now through early 2007. This commentary introduces the first survey, which centers on copper production.
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JOM World Nonferrous Smelters Survey, Part I: Copper
[p. 21
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Author(s): Joel P.T. Kapusta
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| In the World Copper Smelter Survey, data collected in 2003 summarizing the operations and equipment of 52 operating copper smelters were compiled. Included are smelters from Russia and China, as well as two smelters to be commissioned in 2004. This article features six pages of tabular highlights from the massive 2003 survey. This download also contains spreadsheets so that the user can sort and graph the data as desired. NOTE: TMS members may download a .zip file that comprises a PDF of the article as well as the original spreadsheets used to develop the article in Excel format. To access the .zip file, visit the TMS Members-Only Site and click the "JOM Smelter Surveys" link from the Main Menu.
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Foundation News
[p. 11
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Author(s): Anonymous
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In 2003, TMS and the TMS Foundation awarded scholarships and grants to outstanding students to assist them in their pursuit of careers in materials science and engineering. This issue of Foundation News lists those award recipients.
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In the Final Analysis
[p. 2
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Author(s): James J. Robinson
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The JOM Technical Emphasis Calendar offers a reliable prediction of the magazine's content for the coming year, representing the effort and interests of a broad spectrum of society members. At least that is the intent. To learn whether readers are truly satisfied with the content of JOM, a survey is included in this issue and described in this editorial.
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News and Update
[p. 4
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Author(s): Anonymous
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Featuring nominees for the TMS Board of Directors as well as a review of the global copper industry in 2003.
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Meetings Calendar
[p. 63
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Author(s): Various
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A monthly round-up of soon-to-be-held meetings and upcoming calls for papers.
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Materials Resource Center: Jobs, Consultants, Marketplace
[p. 69
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Author(s): Anonymous
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Positions and services available. (You may view "Consultants Directory" or "Classifieds" in HTML format or click on the button to download both departments as they appear in the print version of the journal.)
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End Notes: Things Other
[p. 72
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Author(s): Brendan Baker
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Featuring "Crossing Borders to Engineer a Better Future, Part I: From Canada to Africa"
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