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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

The partial reduction of hematite to magnetic iron oxide.

Sopko, Michael. D. January 1961 (has links)
The iron and steel industry has been and still is faced with rising capital and operating costs. The capital cost of a blast furnace complete with coking ovens and all other raw material facilities is in the order of fourty million dollars and up. In addition each ton of raw material carries the cost of removal from the pit or mine, possible beneficiation costs, plus the high cast of transportation. These costs, it is to be noted, are also increasing. To meet this challenge the industry decided to embark on a twofold program of research.
22

Partial reduction and magnetic concentration of hematite.

Jones, Peter. E. January 1960 (has links)
The steel industry today is faced with rising costs in every phase of production. The capital cost of a blast-furnace complete with coking ovens and all other raw material facilities is in the order of $40 million and up. In addition, each ton of raw material delivered to the blast-furnace carries the cost of removal from the pit or mine, plus the high cost of transportation by boat or by rail. Packard (1) reports that the United States steel companies spend nearly $20 million in research annually, for two main reasons.
23

A study of the mechanism of rust formation.

Smith, Gordon. W. January 1961 (has links)
The wastage of metals due to corrosion has become an important engineering problem in recent years. The growing demand for, and increasing cost of materials, and the cost of shutdown and labour involved in making replacements, makes every effort to understand corrosion worthwhile. The annual cost of corrosion in Canada has recently been set at $300 million (1). This figure is only approximate, because an estimate of this type is extremely difficult to make. A breakdown of the figure is given in Table I.
24

Inverse Segregation in Aluminum-Copper Alloys.

Youdelis, William V. January 1956 (has links)
Segregation which occurs in slowly cooled castings and in the direction indicated by the equilibrium diagram is called "normal segregation". The first crystals to separate from the molten alloy during solidification are rich in the higher melting point alloy and occupy a position close to the mold face. As the solidification proceeds the growing dendrites push before them the residual liquid which is becoming continually enriched in the lower melting point alloy (usually the alloy of high solute concentration). [...]
25

Mechanisms of Solidification in Binary Alloy Castings.

Youdelis, William V. January 1959 (has links)
The demands of present day industry for machines of ever increasing complexity and durability has accentuated the need for the improvement in the art of metal casting. This particular method of shaping metals has in fact become so expedient, that a concerted effort is being made to overcome the multitude of practical problems that still exist in the casting industry. Many of the solutions to these problems, particularly those concerning ingot quality, are only empirical and are not based on the knowledge of the fundamental mechanisms of solidification. [...]
26

The recovery of copper from copper matte.

Finlay, James. E. January 1954 (has links)
Note: Missing page 76. / The importance of the metal copper in our present day civilization is a result of a growing dependence upon electric power in industry and in the home. In addition to its high electrical conductivity, copper because of its thermal conductivity and the physical properties of its alloys with zinc, nickel, aluminum and tin, is also in demand for a great number of nonelectrical applications. The demand for large tonnages of high-purity low-cost copper has necessitated the development of smelting plants operated at large capacity and under careful control to obtain maximum efficiency.
27

The extraction of lithium from spodumene.

Sharratt, Harold. J. January 1955 (has links)
Although lithium occurs more commonly in the earth's crust than lead or tin, it is one of the least known of the lesser used metals. Demand for it prior to World War l was almost nil, but with the great technological advances that always accompany warfare it fast became important in numerous applications. Lithium was first discovered (1) by Arfvedsen in Sweden in 1817 while analyzing a sample of petalite – a lithium aluminum silicate. It was named after the Greek "litheos", meaning "stony", because it was thought to occur only in minerals.
28

Corrosion Behaviour of Welded Low Alloy Steel.

Briggs, David C. January 1958 (has links)
One of many corrosion problems confronting engineers is the failure of metal structures caused by specific corrosive attack at welds. Such attack is especially dangerous when more rapid than the normal corrosion rate of the material, and usually occurs in the following forms: (a) Specific attack of weld metal; (b) Specific attack of parent metal adjacent to a weld deposit; (c) Intergranular corrosion of weld or parent metal in stainless steel due to "sensitization".
29

Scaling studies in sea water distillation.

Jue, Bruce. C. January 1960 (has links)
Industrial growth, population increase and rising living standards have drastically increased the world's demand for fresh water over the last few decades. Present supplies are adequate to meet the needs in many areas, but there are numerous locations where shortages already exist. As growth and development continue this problem will almost certainly become more acute and an effort is being made to evaluate possible ways of easing the situation.
30

Noble metals placer formation an offshore processing conduit /

Welkie, Carol J., January 1976 (has links)
Thesis (M.S.)--University of Wisconsin--Madison. / Typescript. Includes glossary. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 86-88).

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