Abstract This paper discusses the Ray Copper Mine in Arizona. Arizona is the largest producer of copper in USA. There are some other states where copper reserves have been discovered but Arizona by far remains the leading copper-producing state accounting for 65 percent of the total US copper-production. Copper and its by-products represent over 80 percent of Arizona's nonfuel mineral value.
Abstract This paper discusses how Chemical Mechanical Planarization (CMP) is one of the most effective methods in achieving adequate local and global surface planarization and how chemical mechanical polishing of copper attracts a lot of interest. It examines the effects of different factors including the slurry, polishing pads and down force etc. on the quality of planarized copper layer in CMP Cu. It also presents, a new CMP copper technique with the name of ?Abrasive-free polishing (AFP)?.
Outline
Introduction to CMP and CMP Copper(Cu)
Techniques of CMP copper Removal Mechanism
Slurry-- Chemistry
Slurry?Abrasives Particles
Processing Factors
Polishing Pads
Abrasive-Free Polishing of Copper-a New Technique
Conclusions
From the Paper "Recent years have witnessed the rapid development of using copper (Cu) for low resistivity electrical connections in microelectronic devices.1,2 In fact, copper is one of most commonly used pure metals in the electrical industry because of its low conduct resistivity of about 6?10-8W-m and excellent mechanical properties as well. There are various methods to deposit Cu thin films, for example, electroplating, electroless plating, sputtering and thermal evaporation can be used.3.4 The copper thin films achieved by these techniques, especially those from the electrochemical techniques, are not planar enough to promise a successful multilevel interconnection. However, in fabrication of a logic device with five or more layers, at least one layer should be perfectly planar. Lack of layer planarity may lead to severe problems for photo-lithography (such as insufficient focus depth) and dry etching in sub 0.5 mm 5. Chemical Mechanical Planarization (CMP) is one of the most effective methods in achieving adequate local and global surface planarization.6 Therefore, chemical mechanical polishing of copper attracts a lot of interests in recent years."
Abstract This paper introduces the compositions and operating parameters of cyanide and acid copper plating baths. The advantages and limitations of two electroplated copper interconnection methods are compared. Furthermore, a state of the art copper electroplating technique, namely, super filling copper plating, is investigated. Finally possible research endeavors to extend this technique are rendered.
From the paper:
From the Paper " Copper (Cu) is one of most commonly used pure metals in the electrical industry. This is because that copper has a low conduct resistivity (about 6?10-8W-m), which is fit for the low resistivity electrical connections. There are various methods to deposit Cu film; for example, ECD1 (electroplating and electroless plating), PVD2 (sputtering and evaporation) and sometimes CVD methods3 can be used. Among these techniques, electroplating is the one with the least cost and the highest deposition rate which can be controlled properly by varying the applied current. Most important of all, the thickness of the copper coating deposited by the electroplating can be as high as several centimeters (such as in the electro-forming technology). Because of these advantages, the copper electroplating attracts a lot of interests in the microelectronic fabrications in recent years."
Abstract This paper discusses the Montana copper mines, which, at the turn of the 20th century, were a focus of desperate conflict very unique for any place and any time. The paper describes the backgrounds of the three Copper Kings - William Clark, Maracus Daly and F. Heinze , and the battle these men waged amongst themselves for control of the mines. The day to day life of the minors, the conditions they toiled under, and the legacy that the copper wars of Montana had on the labor practices we enjoy today are also discussed.
From the Paper "Daly and his partners bought up as many adjoining properties as they could get their hands on and then imported laborers from around the world. He especially liked the Irish or course because he was born there. What Daly didn't know at the time was that they were sitting on the largest copper sulfide deposit in the Americas (7). He built a smelter at Anaconda which was 26 miles west of Butte and connected it by rail with Butte. In 1882, he decided to mine the copper ore and increase production (3). Daly's decision to mine the pure copper or glance coincided with two major industrial advances, the dawning of the electrical age and the invention of the telephone. In 1876, at the Centennial Exposition in Philadelphia, Alexander Graham Bell introduced the telephone. Then in 1880 Edison began to really develop his ideas for transporting electricity for city lights and both new inventions needed copper wire (7). "
Abstract This report will highlight three key areas of unmet potential where both federal and provincial governments can play an important role in economic stimulation: wind energy products; recycling copper: new facilities; and, looking at what happens after the mine shuts down?
Abstract This paper examines Alzheimer?s; it's aetiology and symptoms, in order to question the orthodox and alternative treatments available. It discusses the considered main causes that include zinc, copper, iron and aluminium, as well as including a brief overview of the accepted commonest risk factors. It is concluded by considering and suggesting, that ginkgo biloba is the main contender as the alternative to orthodox medicine in treating and preventing, Alzheimer's disease.
Outline
Abstract
Introduction
Chapter 1
An Overview of Alzheimer's Disease ? Definition, Aetiology and Risk Factors
Associated Structural Abnormalities of AD
Beta Amyloid Plaques (BAPs)
Neurofibrillary Tangles
Risk Factors of AD
Chapter 2 ? The Biometals
The "Normal" role of Zinc
The Paradoxical Role of Zinc
Iron
Copper Aluminium
Free Radicals and Oxidative Stress
The Cholesterol Theory
Chapter Three ? Ginkgo Biloba
Ginkgo Biloba as an Antioxidant and Preventative
Vitamin ?E? and Other Free Radical Scavengers
Chapter Four - The Role of Orthodox Treatments
Nerve Growth Factor (NGF), One of the Neurotrophic Factors
Selegiline
Oestrogen Replacement Therapy (ERT)
Metal Chelation Therapy
Non-Steroidal Anti-Inflammatory Drugs
Chapter Five ? Conclusion
From the Paper "Copper is another essential trace mineral in the human body; it is a constituent of many enzymes and takes part in the absorption of iron and in melanin formation. Lack of copper may result in anaemia and bone changes. Estimated safe and adequate dietary intake is 1.5-3.0 mg/day for adults, and 0.4-0.6 mg/day for infants (Tortora and Grabowski, 2000). Copper plays a crucial role, with cholesterol, in nutrition and normal brain function. Recent evidence indicates that copper and cholesterol may both be important factors in the aetiology of AD. Sparks et al (2003) explains how trace amounts of copper (0.12 ppm) added to water and given to cholesterol-fed rabbits induced BAP accumulation, including senile plaque-like structures in the hippocampus and temporal lobe."
Abstract The paper is a comparative case study describing the activities of an oil company with that of copper exporting African nations. Referring to the case of Saudi Aramco Oil, the paper highlights the involvement of the various large oil companies based in the United States together with that of the Saudi's and the effects, positive and negative, that resulted from this arrangement in terms of pricing and growth. The paper then discusses the manner in which major copper producers plan their operation in establishing forward contracts with selected buyers and discusses the benefit of this operation. The paper concludes with a comparison of the similarities between the two operations.
Outline:
Summary of the case
Analysis of concepts
Application to the case
From the Paper "Saudi Aramco is the biggest oil company in the world, ranking first in global sales, production and reserves. Owned by the Saudi Arabian government, the company can exert great pressure on other oil-producing lands; however, because it is not blessed with integrated refining and marketing operations, Saudi Aramco becomes a "price-taker" when oil demand plummets. The history of Aramco is very much one of US involvement: in 1948, Exxon and Mobil joined up with Standard Oil of California and Texaco to produce Aramco. In 1951, the Saudi government agreed to allow the aforementioned companies to retain their ownership in Aramco just so long as the government received 50 percent of their profits. Not long thereafter, though, the Saudis saw how the major US oil companies were able to bring the Iranian government to ruin when Iran made the mistake of "getting uppity" and nationalized British oil holdings; put simply, the major US oil companies - along with the CIA - engineered the return to power of the Shah, and he made sure to give the big US corporations a monopoly over the nation's oil-producing sector."
Tags: oil, opec, embargo, oligopoly, risk, management, wertical, intergration
Abstract This paper provides an insight into brass, a useful alloy of two metals, copper and zinc which has been used for cultural uses and ornamentation since the 13th century BC. It examines how the porosity, or the ratio of the volume of interstices of a material to the volume of its mass, can be reduced in order for brasses of all compositions to be worked or hardened to form wires, fittings or ornaments with the most utilitarian strength, elasticity or ductility features.
Outline
Introduction
Brass
A Thousand Years of Brass-Making
Phase Diagram for All Brasses
Density of Brass Varieties
Porosity in Brass
Metal Porosity--in its Place
Manufacturing Methods to Reduce Porosity
Post-Manufacturing Methods that May Reduce Porosity
Unavoidable Internal Change Mechanisms Possibly Affecting Porosity
Summary and Conclusions
From the Paper "As with many metals and alloys, brass is often worked after its formation, not merely for shaping into the desired form, but also to alter for improvement one or more of its physical properties: Strength or hardness, ductility or elasticity, as examples. The methods are generally lumped as a number of "hardening" types, although their purposes rarely include the reduction of porosity, per se. Some are carried out at room temperature (called "cold work"); others are performed at a variety of elevated temperatures, each having its own intended effect (called "hot working")(14:7-9)."
Abstract This paper considers the history of telecommunication and the types of evolving technology and makes a comparison of these and the need and importance of the next phase of transmission, Fiber Optic Cable Networking (FOCN). The paper also includes a brief discussion of the Telecommunication Act of 1996, which is meant to facilitate the decision process of consumers between copper or fiber optics cable and, ultimately, whether a trenchless or open-cut technique is best for installation purposes.
From the Paper "In today's reality, the technology is constrained by network dependencies. It is especially true in cases like communications, computing, and power supply. Innovations such as telephone analog switching systems that convert signals to photonics and optical/photonic systems using light transmission have already changes the way the future is approached. Molitor, 2003, explains, "Light changes polarity one-quadrillion times per second. Scientists already have succeeded in switching light 100 trillion times per second (terabits). Emerging evidence that the speed of light may be exceeded by a factor of 10-1,000-fold suggests future threshold potentials" "
A review of an experiment that determined the reagent that would be limiting and the mass of the precipitate that would be formed in a chemical reaction.
Abstract The paper predicts the mass of precipitate that would be produced by the reaction of 2.00 g of strontium chloride with 2.00 g of copper (II) sulfate pentahydrate in 75 mL of water. The paper lists the materials utilized in this experiment, the procedure and the data collected. The paper provides the calculations used and shows how the prediction that was made turned out to be accurate.
From the Paper "The actual mass of the precipitate is 0.29 g. However, this is not entirely accurate. When removing the filter paper from the funnel the paper ripped, causing some of the precipitate to fall off onto the paper towel below. As a result, the observations are not entirely accurate because the mass of the filter paper and the precipitate should be higher. This also caused the calculation of the actual mass of the precipitate to be slightly lower than it should be. This was a human source of error, as it cannot be fixed after the error was made."
Tags: strontium, chloride, copper, (II), sulfate, pentahydrate, filter, paper
Abstract Sintering, which is a stage of powder metallurgy, is a thermal process that creates inter-particle welds. It is where powder compacts are annealed in a controlled atmosphere to a temperature at which solid-state diffusion occurs. On the other hand, recrystallization is the process of the formation of new strain-free grains from initially cold-worked grains. This paper examines an experiment that had, as its objectives, the intention of examining of the effects of sintering and recrystallization on the microstructure and the hardness of the specimens. The samples used are copper and copper-zinc powders for sintering and brass for recrystallization. The paper shows that the copper and copper-zinc powders are compacted and are sintered in a nitrogen-containing atmosphere at different temperature and time settings. The brass samples are cold-worked and are annealed at different temperature and time settings. The paper includes tables.
Paper Outline:
Abstract
Introduction
Experimental Section
Results and Discussion
Conclusion
References
From the Paper "When a polycrystalline metal is cold worked, the grain boundaries act to interrupt the slip processes that occur in the crystals. The lattice adjacent to the grain boundaries is much more distorted in the center of the grains. Decreasing the grain size increases the grain boundary area and, as a consequence, the volume and the uniformity of the distorted metal. This effect decreases the number of possible sites of nucleation and, therefore, the smaller the grains of the metal before cold work, the greater will be the rate of nucleation and the smaller the recrystallized grain size for a given degree of deformation."
Abstract European Industrialization and Effect on Working Women
Women Inheriting Businesses, Marry into Craft
Metalsmiths, Silvercasters, Bucklemakers
Metalsmithing Guilds Persecute
Rise in Jewelry Making
Greater Recognition for Individual Work
Sexual Division of Labor - Commitment of Children
Still Men Described as "Opening the Door"
Majority of Art Professors are Female as well as the most
Well Known Metalsmith (ex. Helen Shirk)
Abstract This paper focuses on the hardware behind fiber optics technology, particularly the cabling. The author discusses how fiber works and what it can do and why it's a technological leap over previous networking technologies, which rely on copper wiring. The author points out some of the advantages and applications of fiber optic technology.
Abstract This paper is about investment opportunities in Zambia. Zambia is landlocked and shares its boundaries with eight other countries. It is part of the high African plateau, everywhere more than 1,0001 m above sea level, except in the valleys of the Zambezi River and its tributaries, the Luangwa and Kafue. The Zambian economy revolves around the copper industry, the source of virtually all export revenue.
