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By Robert E. Green

Experiments were performed in order to investigate the influence of magnitude of driving force, recouery, and previous heat treatment on grain boundary migration in deformed aluminum crystals. The frequency of occurrence of strain-free grains possessing Preferred crystallographic orientations was studied both as a function of heat treatment and as a function of amount of deformation of the matrix crystal. Aluminum of such composition as to exhibit precipitation-hardening behavior was used. CONSIDERABLE work has been devoted to the factors influencing grain boundary migration in metals.1'52 Aust and Rutterl-9 have studied grain boundary migration into matrix crystals containing a striation substructure, which provided a thermally stable driving force during the course of the migration experiments. These authors state that, while variations in the striation pattern were sometimes observed, it was possible to obtain reasonably uniform and reproducible striation structure by careful control of the solidification conditions. Admittedly, this source of driving force is a unique one and has served well in numerous experiments. However, although the striation substructure provides a thermally stable driving force, the subject of its reproducibility from crystal to crystal is questionable. In fact, Aust and Rutter3 attribute the scatter shown in some of their experimental points and several anomalies in boundary migration rates to variations in the substructure driving force along a single specimen. A further limitation on striation-induced driving force is that the driving force cannot be varied over wide ranges in a controlled manner. More often used as a source of driving force is the strain energy stored in a crystal during plastic deformation. This type of driving force has the disadvantage that it is not thermally stable due to recovery taking place simultaneously with the grain boundary mobility measurements. On the other hand, this strain-induced driving force is very reproducible from crystal to crystal since it is very easy to grow single crystals possessing the same purity and crystallographic orientation and then to strain them identically. In order to measure grain boundary migration rates two different methods are primarily used. Most often the technique employed is the heat-cool-etch method1' which involves thermal cycling, while the other technique, developed by Graham and Cahn11 using an X-ray diffractometer and goniometer furnace, involves continuous heating only. Thus the influence of thermal cycling vs continuous heating is a factor to be considered in grain boundary migration rate measurements, particularly in cases where the source of driving force is the strain energy stored in the deformed matrix, and recovery is likely to occur. Numerous recent investigations have shown that extremely small impurity additions to zone-refined metals exert a marked effect on grain boundary migration rates1-5, 9, 12-27 and a few have considered the effect of the distribution of impurities.28-35 The concentration of impurities and their distribution as influenced by heat treatment must also be taken into account in migration-rate studies. In the present article consideration is given to the influence of the magnitude of driving force, recovery, and previous heat treatment on grain boundary migration rates. In order to vary the driving force over a large range it was necessary to use as a source of driving force the energy stored in the matrix crystal during plastic deformation. A majority of the investigations were performed on aluminum specimens which were of such compositions as to exhibit precipitation-hardening behavior.

Jan 1, 1965

The work that has formerly been done by the Waste-reclamation Section of the War Industries Board has been tranferred to the Department of Commerce and will be continued as the "Waste-reclamation Service" of this Department. The plan contemplates the establishment of a national waste-reclamation system-comprehensively organized, effective and systematic, and animated by a sympathetic understanding of the purposes and principles of the Service. It is the expectation of the Service that the work will be taken over by the several municipalities or other local governments and made permanent through the creation of a department or bureau for the salvage of waste materials. The local Waste-reclamation Council should be composed of representatives of cooperating national organizations, selected by the mayor; or chief executive officer of the city, town, or village. It will be the duty of the Council to inaugurate an educational campaign to conserve materials so as to make less waste, together with a reclamation movement that shall reclaim the residue of waste in the community, thus conserving the resources of the country both in man power and in materials. The most important materials to reclaim at the present time are: paper, steel, copper, wool, iron, brass, cotton, zinc, aluminum, rubber, babbitt metal, tin-foil, lead, tin and leather.

Jan 8, 1919

Arkansas Geological Survey, Rooms 443-447 State Capitol, Little Rock, Ark George C Branner, State Geologist A list of available publications will be sent upon request Publications issued by the U. S Bureau of Mines, U S Geological Survey and Oklahoma Geological Survey, pertaining to' Arkansas, are also available through this Survey office. Annual Reports may be had for the following years. 1890, 3147, 1891, 81 35; 1892, $1 10 Other available publications: The slates of Arkansas, by A H. Purdue, with a bibliography of the geology of Arkansas by John C Branner (1909), $1.10, Coal mining in Arkansas, pt 1, by A A Steel (1910), 3175, An outline of the physical features of Arkansas, by George C Branner (1927), free, An outline of the metallic minerals of Arkansas, by George C Branner, free, Bulletin 3, The geology of the Arkansas Paleozoic Area, by Carey Croneis (1930), $3 20, Bulletin 4, St Peter and older Ordovician sandstones of northern Arkansas, by A W Giles (1930), $1 95, Bulletin 5, A geomagnetic survey of the bauxite region of Arkansas, by Noel H Stearn (1930), 80 cents, Information Circular 1, A barite deposit in Hot Spring County, by B Parks and George C Branner (1932), $1, Information Circular 2,

Jan 1, 1933

By J. G. Paterson, J. A. Meech

Abstract-Activated carbon is a strong adsorbent for amyl xanthate, capable of removing from solution up to a quarter of its own weight in xanthate. In selective flotation systems where depression is unstable, separation efficiency increases with activated carbon additions. The improvements observed are brought about by two mechanisms. First, by removing stripped and residual collector ions from solution, competition between depressant and xanthate is reduced and depression is stabilized. In addition, the texture of the froth phase at high pine oil concentrations is modified by activated carbon such that better drainage between the air bubbles takes place, alleviating the mechanical entrapment of depressed mineral particles. In treating a bulk copper/lead concentrate produced from GECO ore, selectively between galena and chalcopyrite is increased when activated carbon is used. Although the rate of flotation of galena is marginally lowered by activated carbon, a small extension in the duration of flotation allows the lead recovery to increase by 19% at the same recovery of copper. An addition rate of 0.75 kg/ton (1.5 lb/st) of bulk concentrate is suggested as optimum from this testwork. However, the actual level wed in the mill is dependent upon the residual concentrations of collector and frother in the bulk concentrate Pulp.

Jan 11, 1978

ENGINEERS AVAILABLE (Under this heading will be published notes sent to the Secretary of the Institute by members or other persons.) Member, aged 25, recent graduate, with some experience in laboratory of steel plant, desires position as metallurgist or assistant in copper, aluminum, or steel works. No. 118. Member, aged 52, technical graduate, with 20 years' experience as engineer with coal-mining companies, desires position as engineer or superintendent of coal mine. No. 119. Member, aged 39, technical graduate, with extended experience in surveying, assaying, milling, and copper smelting, desires position along cyaniding, concentration, or copper-smelting lines. No. 120. Member, aged, 38, technical graduate, with several years' experience in research work, in mine operation and as professor of mining engineering, is desirous of engagement in planning concentration and metallurgy of odd and difficult ores. No. 121. Member, aged 32, graduate M. I. T. in mining and metallurgy, at present and for last five years superintendent of Western lead smeltery, will consider engagement with solid company, if opening promises advancement. Specialty, smelting of lead ores, high in lead and zinc content. Ten years' experience in the operation, design, and erection of a large lead plant. Now desirous of bettering position.. No. 122.

Jan 8, 1914

By Ben B. Cox

Oil produced in Iraq for export during 1938 was 31,354,090 bbl., or a daily average of 85,901 bbl; This is an increase of 182,614 bbl., or 0.5 per cent over 1937. All oil exported was produced from the Kirkuk field. The Khanaqin Oil Company, Ltd., a subsidiary of the Anglo-Iranian Oil Company, Ltd., continued to supply local market requirements from its Naft Khaneh field in the Transferred Territories. Slightly more than 32,000,000 bbl. was produced in Iraq, a small part of which was used in field operations. During the year 12 wells were completed and 9 wells were drilling at the end of the year. Of the completions, 5 were producers and 1 was an oil-water level observation well in proved fields, and 6 were listed as failures. Basrah Concession The outstanding event of the year was the granting, by the Kingdom of Iraq, of a 75-year concession embracing approximately 89,000 sq. miles to the Basrah Petroleum Company, Ltd., a British company with French and American participation. The concession covers all parts of the Kingdom, its territorial waters, islands, submerged lands, and its interest in the Neutral Zone separating Iraq and Saudi Arabia that

Jan 1, 1939

By J. R. Finlay

THE other day, I fell into conversation with two gentlemen who desired to improve the condition of the people; so that the talk was semi-political. They seemed to agree that I was inclined to be "con-servative," "reactionary," perhaps an "evolutionist," looking upon "reform" with suspicion. Finally I rejoined somewhat in this manner: "You attach to me phrases that I have heard all my life but which convey no meaning to me. It is quite true that I do not make a fetish of terms like reform, liberty, democracy and so forth; neither do I worship the idea that `things are good enough as they are,' `leave well enough. alone' and so forth. There is more satisfaction in building something up than in tearing something down, or in just maintaining something that is already built. Progress is a popular word; but what is progress? In my opinion it is comprised, so far as public welfare is concerned, of two elements: Improvements in production of goods and knowledge; improvements in keeping order." This substitute for politics, economics, reform, pro-gress, conservatism, radicalism, democracy, socialism, monarchism and all the phrases of public welfare may seem over-simple; perhaps it is, but at least it defines something. It seems to me to be at least worth attention.

Jan 4, 1922

By Ben B. Cox

Oil produced in Iraq for export during 1938 was 31,354,090 bbl., or a daily average of 85,901 bbl; This is an increase of 182,614 bbl., or 0.5 per cent over 1937. All oil exported was produced from the Kirkuk field. The Khanaqin Oil Company, Ltd., a subsidiary of the Anglo-Iranian Oil Company, Ltd., continued to supply local market requirements from its Naft Khaneh field in the Transferred Territories. Slightly more than 32,000,000 bbl. was produced in Iraq, a small part of which was used in field operations. During the year 12 wells were completed and 9 wells were drilling at the end of the year. Of the completions, 5 were producers and 1 was an oil-water level observation well in proved fields, and 6 were listed as failures. Basrah Concession The outstanding event of the year was the granting, by the Kingdom of Iraq, of a 75-year concession embracing approximately 89,000 sq. miles to the Basrah Petroleum Company, Ltd., a British company with French and American participation. The concession covers all parts of the Kingdom, its territorial waters, islands, submerged lands, and its interest in the Neutral Zone separating Iraq and Saudi Arabia that

Jan 1, 1939

(The following list contains the names of those members of the Institute of whose connection with military service we have only recently become acquainted; it also includes the names of a few who have recently been promoted or transferred, indicated by a *. A complete list was published in the Year Book, issued as a supplement of the Bulletin for March, 1918.) ALLEN, Roy H., Capt., Air Service, Bureau of Aircraft Production, Washington, D. C. *AMIDON, CLAUDE E., Chemical Warfare Section', Astoria, L. I. *ARCHBALD, HUGH, 311th Infantry, 78th Division, American E. F. ASKIN, THOMAS B. H., Radio Station, Cavite, P. I. *AYER, FRANK A., Lieut., Commanding Officer, -270th Aero Squadron, American E. F. BARBA, W. P., Lieut. Colonel, Ordnance, U. S. A., Washington, D. C. *BARRETT, LESLIE P., 1st Lieut., 5th Field Artillery, American E. F. BLICKENSDERFER, F. C., 1st Lieut., N. A., Ordnance Dept., Edgewood Arsenal, Edgewood, Md. *BROOKS, FLOYD R.., Lieut., Canadian Engineers, Seaford, England. BROWN, GEORGE M., Co. G, 1st Replacement Regiment, Washington Barracks, D. C. *BRUNEL, LOUIS J., Lieut., 5th Field Artillery, Brigade Headquarters, American E. F. *BRUNTON, D. W., Cons. Engr., Naval Consulting Board, Washington, D. C.

Jan 11, 1918

By George Beavers

FLASH roasting of iron concentrate is in the experimental stage at Copperhill. The problem is peculiar in that the iron concentrate is predominantly pyrrhotite; the ratio of that mineral to pyrite being 5 to 1. Results so far indicate that the heat, generated in roasting a material containing 52.0 per cent iron and 38.0 per cent sulfur, requires special handling and for this reason the installation costs per ton of roaster feed may be too great to compete with hearth roasting. Interesting features of flash roasting at Copperhill are: 1. The sulfur dioxide content of the roaster exit gas can be varied between wide limits. Eight per cent sulfur dioxide gas, with 1.30 per cent sulfur in the calcine, has been common practice and gas up to 13.0 per cent sulfur dioxide has been possible. 2. Temperatures of the exit gases are very high. When roasting 60 tons or more of iron concentrate per 24 hr. in a modified Wedge roaster, the temperature in the roaster rises to 2000° F. and the calcine is lowered to 0.20 per cent sulfur. If the entire roaster system could be constructed to withstand such temperatures, ideal roasting conditions would obtain as regards sulfur elimination and tonnage roasted.

Jan 1, 1934

By Chingyuan Y. Li, C. Y. Hsieh

Realizing that aluminum will have a great role to play in the coming industrialization of China, Chinese geologists have long been looking about for some aluminum deposits. The possible sources appear to be alunite, the alumina-rich shales, and the bauxite deposits. The locations of deposits are shown in Fig. I. Alunite Our attention was first directed to the alunite deposits along the southeastern coast of China. Table I summarizes the reserves now believed to exist in that region. Other alunite deposits have been found in Kiangpei, Szechuan province; Charming. Liuyang and Hsanshan, Hunnan province Tsingchow and Chowyuan, Shantung province. No reserve figures are available. High-alumina Shale Shale high enough in aluminum to serve as a source of that metal has been found in northeastern China(Tab1e 2). In Manchuria, the Manchuria Light Metals Co., at Antung and Fushun, operating under Japanese control, has been the only active producer of aluminum. It is not known, however, whether the company uses local raw materials or imports ore from elsewhere.* Shantung Bauxite Bauxite was first recognized in China at Paoshan, Shantung province. Although the reserve is reported to be large (estimated at 271 million tons), the high content of insoluble residue (SiO2) and mineral composition (diaspore) are dis-

Jan 1, 1948

By Chingyuan Y. Li, C. Y. Hsieh

REALIZING that aluminum will have a great role to play in the coming industrialization of China, Chinese geologists have long been looking about for some aluminum deposits. The possible sources appear to be alunite, the alumina-rich shales, and the bauxite deposits. The locations of deposits are shown in Fig. I. ALUNITE Our attention was first directed to the alunite deposits along the southeastern coast of China. Table I summarizes the reserves now believed to exist in that region. [ ] Other alunite deposits have been found in Kiangpei, Szechuan province; Channing, Liuyang and Hsanshan, Hunnan province; Tsingchow and Chowyuan, Shantung province. No reserve figures are available. HIGH-ALUMINA SHALE Shale high enough in aluminum to serve as a source of that metal has been found in northeastern China (Table 2). [ ] In Manchuria, the Manchuria Light Metals Co., at Antung and Fushun, operating under Japanese control, has been the only active producer of aluminum. It is not known, however, whether the company uses local raw materials or imports ore from elsewhere.* SHANTUNG BAUXITE Bauxite was first recognized in China at Paoshan, Shantung province. Although the reserve is reported to be large (estimated at 271 million tons), the high content of insoluble residue (Si02) and mineral composition (diaspore) are dis-

Jan 1, 1946

By Chingyuan Y. Li, C. Y. Hsieh

Realizing that aluminum will have a great role to play in the coming industrialization of China, Chinese geologists have long been looking about for some aluminum deposits. The possible sources appear to be alunite, the alumina-rich shales, and the bauxite deposits. The locations of deposits are shown in Fig. I. Alunite Our attention was first directed to the alunite deposits along the southeastern coast of China. Table I summarizes the reserves now believed to exist in that region. Other alunite deposits have been found in Kiangpei, Szechuan province; Charming. Liuyang and Hsanshan, Hunnan province Tsingchow and Chowyuan, Shantung province. No reserve figures are available. High-alumina Shale Shale high enough in aluminum to serve as a source of that metal has been found in northeastern China(Tab1e 2). In Manchuria, the Manchuria Light Metals Co., at Antung and Fushun, operating under Japanese control, has been the only active producer of aluminum. It is not known, however, whether the company uses local raw materials or imports ore from elsewhere.* Shantung Bauxite Bauxite was first recognized in China at Paoshan, Shantung province. Although the reserve is reported to be large (estimated at 271 million tons), the high content of insoluble residue (SiO2) and mineral composition (diaspore) are dis-

Jan 1, 1948

By R. S. Shoemaker, F. W. McQuiston

EMPEROR GOLD MINES Vatukoula, Fiji 1974 Operating Data to July 1 ORE DESCRIPTION: Ore bodies occur in basalt and associated ash beds overlain by andesite tuffs and sediments. The basalt in much of the ore mined is weathered with alteration of olivine to serpentine and iron oxides, and augite to chorite. The most important host minerals for gold are the tellurides sylvanite and hessite. Next in importance the sulphide s, pyrite, marcasite and arseno-pyrite. A small amount of free gold also occurs. Chalcopyrite, sphalerite, tetrahedrite, bornite, galena and native tellurium are present in small quantities. TYPE OF MINE: Underground and open pit ORE HAULAGE TO MILL: 3.5 ton bottom dump skips from underground. 7 ton trucks from open pit. CAPACITY IN TONS/24 HRS: 1345 short tons ASSAY HEADS (1973): 0.232 oz Au per ton, 0.357 oz Te per ton PRODUCTS: Gold Bullion (400 oz bars) Metallic Tellurium (1 2 lb bars ) RECOVERIES: AU 86.2% Te 88.0% ORE GRINDABILITY: 9.25 Kwh/T TOTAL POWER: 25.7 Kwh/T WATER: Pumped 112 mile to a 318, 000 gallon head tank. Consumption: 2 140 gal per ton, no reclaimed water used. TAILINGS: Pumped 2 /3 mile through 8" pipe. Uphill sections are steel. Downhill sections are fibro asbestos.

Jan 1, 1975

By H. Martyn Chance

I have been induced to present this paper to the Institute because I have been unable to find any publication containing a disctission of this subject. In some of our technical schools and colleges the student is required to construct or copy (generally the latter) a number of profile sections as part of his routine work; but little attention is given to the methods of projecting observed dips and exposures upon the section line, and still less to the method of constructing the under (or above) ground curves. As a result of this lack of instruction every engineer or geologist is compelled to invent for himself a system, or copy the style of others. Geological profile sections have frequently been used to determine underground structure from data obtained at the surface, but the experience of engineers in the anthracite coal-fields has shown that they are to be relied upon only in exceptional instances. The possibility of indicating underground curvatures from dipangles observed at the surface has been found to be limited to a mere approximation of the larger flexures, As a means of predicting the depth and shape of minor rolls, they have been found most unsatisfactory. In the anthracite coal-fields the hypothecated

Jan 1, 1881

By Francis Cameron

Mining is both exciting and rewarding-although at times somewhat frustrating-and we all can have real pride in our industry, in its people, and in its accomplishments. It is, however, with concern that I have noted a deterioration in this Country in what might be called mining's stature and in the growth of a belief in many quarters that our mineral reserves are rapidly approaching exhaustion. In other words, there is a popular image that we are fast becoming a "have not" nation in many respects and that the domestic mining industry can no longer be considered, in the vernacular of Wall Street, to offer much in the way of "growth potential." I do not subscribe to this hypothesis, nor do I believe that the record of the mining industry bears this out. However, let me add that we can, in time, talk ourselves into this frame of mind and we can hasten the day when this very well might come about by unnecessary and unwise legislation or regulation. My remarks today are basically designed to give my reasons for refuting this negative philosophy and to review our record. With your help, I know we can improve our image, and the public's recognition of our industry's peculiar problems.

Jan 4, 1968

By H. Martyn Chance

I HAVE been induced to present this paper to the Institute because I have been unable to find any publication containing a discussion of this subject. In some of our technical schools and colleges the student is required to construct or copy (generally the latter) a number of profile sections as part of his routine work ; but little attention is given to the methods of projecting observed dips and exposures upon the section line, and still less to the method of con¬structing the under (or above) ground curves. As a result of this lack of instruction every engineer or geologist is compelled to invent for himself a system, or copy the style of others. Geological profile sections have frequently been used to determine underground structure from data obtained at the surface, but the experience of engineers in the anthracite coal-fields has shown that they are to be relied upon only in exceptional instances. The possibility of indicating underground curvatures from dip-angles observed at the surface has been found to be limited to a mere approximation of the larger flexures, As a means of predicting the depth and shape of minor rolls, they have been found most unsatisfactory. In the anthracite coal-fields the hypothecatod

Jan 1, 1881

By Howard M. Graff, Sidney C. Bouwer

The economics of mining has traditionally been viewed quite apart from the economics of blast furnace operations. It was realized, of course, that blast furnaces would operate best with good raw materials, but the shipping grade of ore, for example, was decided by a sort of collective bargaining process between the ore producers and the blast furnace operators. The mine operators had to keep their costs down, and were usually successful in convincing management that the ore in any particular deposit was endowed by nature with a certain iron content and that the mine grade could not be raised beyond a certain economic limit. The blast furnace operators would have liked a better grade, but as long as they were able to make a fairly good showing it was more or less accepted that they had to take the ore as it came. The mine operators were able to ship to the nation's blast furnaces thousands of tons of iron ore that would be completely unacceptable by present-day standards. As late as the early 1950's, the major steel companies were witnessing an actual decline in the iron content of their incoming ore supply as the mining companies mined progressively leaner material and upgraded it only enough to pass competitive market requirements

Jan 8, 1965

By Amos P. Brown

PYRITE, the bisulphide of iron, FeS2, is found more or less in all coal-beds: but, as a rule, in certain definite forms. More than any other impurity, it detracts from the commercial value of a coal-deposit, and yet its presence is so universal that it might almost be said that there is no coal entirely free from pyrite. My observation has been confined to the Pennsylvania bituminous and semi-bituminous coals, and to them, therefore, my remarks will be confined. Certain generalizations which I may make, however, will be found of universsl application. The lowest members of the coal-formation, No. XIII. of the Pennsylvania bituminous region, are nearly always pyritiferous, and in many cases highly so. In Cambria county, for instance, coalbed A, the Brookville, is locally known as the " Sulphur seam." The Lower Kittanning, in parts of Clearfield county, is so sulphury as to be almost unmarketable, though otherwise it is a strong locomohive coal. In Mercer county the Pardoe bed, so extensively mined there, carries great quantities of sulphur in the form of pyrite, though usually this can be separated in such a way as to detract little from the market-value of the coal. The other coal-beds of the Lower

Jan 1, 1888

By U. Oko

The cause and the effect of disposing of tailings water from sulfide ore milling operation were examined. Dissolved metallic ions as well as dissolved sulfur-oxygen compounds (polythionates) can prove injurious to life in water streams. Polythionates originate in alkaline flotation circuits and may cause a severe drop in the pH of stream waters. It is proposed that a suitable "aging" period be allotted to tailings water to ensure complete conversion of polythionates to sulfate prior to neutralization and clarification treatment. Discharging alkaline solid-free tailings water without aging will cause downstream acidification. Artificial oxidation of tailings water can be economical only if the concentration of thiosulfate in solution is low. When the concentration is high, it is possible to reduce the concentration greatly by first acidifying the solution, because at a pH below 4 thiosulfate in water reacts to produce a precipitate of elemental sulfur and higher order polythionates. The residual polythionates can then be oxidized at great savings by natural aging or by chemicals such as ozone, chlorine, or peroxide. Chlorine may be an economical reagent for converting polythionates to sulfuric acid but the residual organo-chlorinated compounds can prove to be toxic to aquatic life. Ozone and hydrogen peroxide which do not leave a residue are preferred oxidizers.

Jan 1, 1976