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N. W. H. Mason, J. B. Wilson and J. B. Steel argue that there is no logical conceptual basis, and no empirical data, to support an association between environmental adversity and the occurrence of alternative stable states. While ...
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N. W. H. Mason, J. B. Wilson and J. B. Steel argue that there is no logical conceptual basis, and no empirical data, to support an association between environmental adversity and the occurrence of alternative stable states. While we agree that robust debate on the relative frequency of occurrence of alternative stable states is valuable, any apparent logic in their argument is confounded by misinterpretation and direct misrepresentation of our earlier arguments (Didham et al. 2005), despite the fact that we clarified many of the same issues in response to T. Fukami and W. G. Lee (Didham and Norton 2006). Opinion, not logic or evidence, underlies Mason, Wilson and Steel's argument, and this does little to further our understanding of why some systems exhibit alternative stable states that are resilient to restoration management efforts.
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Steel is an efficient material for structural purposes because of its good strength to weight ratio. The basic requirement in the choice of particular steel is that it must be suitable for the product application and design condit...
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Steel is an efficient material for structural purposes because of its good strength to weight ratio. The basic requirement in the choice of particular steel is that it must be suitable for the product application and design conditions required. It must be available in the product form and shape required and it should be cost effective for the required applications. The versatility of steel for structural applications, rests on the fact that it can be readily available at a relatively cheaper price in a wide range of product forms, and with a useful range of material properties. The key to understanding the versatility of steel lies in its basic metallurgical behavior. This paper briefly describes the recent developments in steel construction technology, which have successfully transformed the market place and how India can take advantage of these developments and what strategies need to be adopted for large-scale introduction of steel intensive building construction in India.
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The 2012 AMS Leroy P. Steele Prizes were presented at the 118th Annual Meeting of the AMS in Boston in January 2012. The Steele Prizes were awarded to MICHAEL ASCHBACHER, RICHARD LYONS, STEVE SMITH, and RONALD SOLOMON for Mathemat...
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The 2012 AMS Leroy P. Steele Prizes were presented at the 118th Annual Meeting of the AMS in Boston in January 2012. The Steele Prizes were awarded to MICHAEL ASCHBACHER, RICHARD LYONS, STEVE SMITH, and RONALD SOLOMON for Mathematical Exposition; to WILLIAM THURSTON for a Seminal Contribution to Research; and to IVO M. BABUSKA for Lifetime Achievement.
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The ability to absorb energy of impact or blast is crucial to the design of army and navy structures. Metallic foams possess low density, energy absorption and vibration damping capabilities. Manufacture of steel foam on an indust...
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The ability to absorb energy of impact or blast is crucial to the design of army and navy structures. Metallic foams possess low density, energy absorption and vibration damping capabilities. Manufacture of steel foam on an industrial scale has not been made so far. At Maynard Steel, inventive developments of steel foam have been made that result in lower weight compared to solid steel. US and international patent applications are pending for these developments. The intent of this paper is to bring awareness to defense and civilian engineers and designers regarding the availability of this new material for applications. It is visualized that the components made using this material will eventually be used among other applications in armored vehicles, naval ships and protective panels for US embassy buildings all over the world.
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Developments in stainless steels, particularly in the latter part of the 20th century have been influenced by economic factors, the needs of industry for improved properties and performance, improvements in steelmaking technology ...
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Developments in stainless steels, particularly in the latter part of the 20th century have been influenced by economic factors, the needs of industry for improved properties and performance, improvements in steelmaking technology and weldability issues. This paper reviews the more recent developments of four important groups of stainless steels namely: Supermartensitic, Superduplex, Superaustenitic and Superferritic types. It describes the evolution of the latest versions as well as important properties and applications. It also discusses weldability problems and highlights possible future research needs in this area.
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The car industry is facing pressure because of the growing demand for more fuel-efficient passenger cars. In order to limit energy consumption and air pollution the weight of the carbody has to be reduced. At the same time, high l...
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The car industry is facing pressure because of the growing demand for more fuel-efficient passenger cars. In order to limit energy consumption and air pollution the weight of the carbody has to be reduced. At the same time, high levels of safety have to be guaranteed. In this situation, the choice of material becomes a key decision in car design. As a response to the requirements of the automotive sector, high strength steels and advanced high strength steels have been developed by the steel industry. These modern steel grades offer an excellent balance of low cost, light weight and mechanical properties.
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Microstructural control is essential to fully exploit the properties of ferritic-austenitic stainless steels. Intermetallic phases are widely regarded as detrimental and their presence is generally considered unacceptable. Whilst ...
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Microstructural control is essential to fully exploit the properties of ferritic-austenitic stainless steels. Intermetallic phases are widely regarded as detrimental and their presence is generally considered unacceptable. Whilst it is recognised that most specifications stipulate that no deleterious third phases are permitted, there are occasions when it becomes important to perform a quantitative assessment. When the limitation of such phases to below a critical level is essential, methods are required to enable accurate and reliable quantification. The work investigated the effects of different techniques for the preparation of both metallographic sections and acetate replicas on the results of subsequent point counting. Manual point count estimates of low intermetallic phase volume fractions (i.e. < 5 %) were made in a range of duplex and superduplex stainless steels. The most promising laboratory method was assessed by an interlaboratory round-robin study. Whilst good repeatability of measurements was achieved at one laboratory, significant differences were apparent in the results of the interlaboratory study, indicating that manual point counting of a low phase volume fraction has inherent limitations, which should be recognised when setting acceptance criteria. Measurement of properties relevant to service remains the preferred way to establish the absence of deleterious levels of intermetallic phase.
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