7,756 research outputs found
Hardness and Microstructure of Binary and Ternary Nitinol Compounds
The hardness and microstructure of twenty-six binary and ternary Nitinol compounds (Ni-Ti, Ni-Ti- Ta, Ni-Ti-Hf, and Ni-Ti-Zr) were studied. A small (50g) button of each compound was produced by vacuum arc melting (VAM). Each alloy was homogenized in vacuum for 48 hr followed by furnace cooling. Specimens from the buttons were then heat treated at 800, 900, 1000 or 1100 C for 2 hr followed by water quenching. The hardness and microstructure of each specimen was compared to the baseline (55-Nitinol, 55 at.% Ni 45 at.% Ti, after heat treatment at 900 C). The results show that sixteen of the studied compounds had higher hardness values than the baseline material with relatively low levels of secondary phase precipitation. Moreover, five of these compounds had hardness values greater than or equal to approximately 660HV (58HRC) with essentially no property-degrading precipitation phases
A fluorometric method for the estimation of tryptophan
The various colorimetric methods now employed for the estimation of tryptophan are not specific for tryptophan but give colored products with many compounds containing the indole nucleus, including indole itself. In order to facilitate studies of the enzymatic synthesis of tryptophan from indole and serine by extracts of Neurospora (1), a search for a rapid, quantitative method for the estimation of tryptophan in the presence of indole was undertaken. Tauber (2) reported that tryptophan gives a green fluorescence when treated with 70 to 72 per cent perchloric acid at room temperature. Modification of this procedure has led to a method for the rapid estimation of tryptophan, without preliminary extraction of indole, in hydrolyzed or unhydrolyzed tryptophan-containing materials
Global Climate Change and Catholic Responsibility: Facts and Faith Response
Citation: Braun G, Hellwig MK, Byrnes WM (2007) Global Climate Change and Catholic Responsibility: Facts and Faith Response. Journal of Catholic Social Thought 4(2): 373-401. Abstract: The scientific evidence is now overwhelming that human activity is causing the Earthâs atmosphere to grow hotter, which is leading to global climate change. If current rates of greenhouse gas (GHG) emissions continue, it is predicted that there will be dramatic changes, including flooding, more intense heat waves and storms, and an increase in disease. Indigenous peoples and the poor will be most severely affected, as will Earthâs wild animals and plants, a quarter of which could become extinct in fifty years. We urgently need to switch to renewable (non-GHG emitting) energy sources, and try to live in a simpler, more sustainable way. In this article, a renewable energy expert, a biochemist, and a theologian have come together to describe the situation in which we find ourselves, and present ideas for a solution that incorporates Catholic social teaching
An evolutionary economic perspective on technical change and adjustment in cane harvesting systems in the Australian sugar industry
Australian sugar-producing regions have differed in terms of the extent and rate of incorporation of new technology into harvesting systems. The Mackay sugar industry has lagged behind most other sugar-producing regions in this regard. The reasons for this are addressed by invoking an evolutionary economics perspective. The development of harvesting systems, and the role of technology in shaping them, is mapped and interpreted using the concept of path dependency. Key events in the evolution of harvesting systems are identified, which show how the past has shaped the regional development of harvesting systems. From an evolutionary economics perspective, the outcomes observed are the end result of a specific history.Crop Production/Industries,
The plastic limit of clays
The plastic limit of soils was first described by Atterberg in 1911. The thread-rolling test was standardised at the US Public Roads Bureau in the 1920s and 1930s, and has subsequently become one of the standard tests of soil mechanics. This paper reviews the original definitions of plastic limit as proposed by Atterberg, and proposes that the brittle failure observed in the plastic limit test is caused by either air entry or cavitation in the clay. Critical state soil mechanics is used to show that the observed range of undrained shear strengths of soils at plastic limit is consistent with this hypothesis. The fallacy that strength at plastic limit is a constant is highlighted, and the implications for geotechnical practice are discussed. </jats:p
Success Strategies Being Implemented in Fresh Milk Supply Chains
Deregulation of the Australian dairy industry, and ensuing supermarket strategies are transforming the fresh milk supply chains. Factors such as increasing consumer awareness, concerns about food safety and environment, innovation, supply chain integration and rationalisation of supply base are adding momentum to this transformation. Milk processors in response to changing market expectations are getting proactive in their relationship with retailers across all aspects of business, innovating to generate sufficient returns from proprietary brands and strategically orienting themselves to develop a mixed customer portfolio and appropriate management structures to service that portfolio. Milk producers are expanding businesses to achieve production and cost efficiencies and strengthening contractual relationships on input and output side for a greater security.Livestock Production/Industries,
CRAFTING SMALLHOLDER-DRIVEN AGRICULTURAL RESEARCH SYSTEMS IN SOUTHERN AFRICA
Research and Development/Tech Change/Emerging Technologies,
General Relativity and Gravitation: A Centennial Perspective
To commemorate the 100th anniversary of general relativity, the International
Society on General Relativity and Gravitation (ISGRG) commissioned a Centennial
Volume, edited by the authors of this article. We jointly wrote introductions
to the four Parts of the Volume which are collected here. Our goal is to
provide a bird's eye view of the advances that have been made especially during
the last 35 years, i.e., since the publication of volumes commemorating
Einstein's 100th birthday. The article also serves as a brief preview of the 12
invited chapters that contain in-depth reviews of these advances. The volume
will be published by Cambridge University Press and released in June 2015 at a
Centennial conference sponsored by ISGRG and the Topical Group of Gravitation
of the American Physical Society.Comment: 37 page
El perro que no ladrĂł: el caso de Juan Carlos RodrĂguez
The extensive body of research associated with the name of Juan Carlos RodrĂguez has failed to receive the attention it deserves. The reasons commonly adduced, by way of explanation, focus upon factors external to the texts themselves. In this article I review two recently published books by RodrĂguez and a celebratory volume with an eye to foregrounding other, internal barriers to RodrĂguezâs reception. These include a cyclical style of argumentation, of the kind associated with symptomal reading; the absence of a clear exposition of the Althusserian problematic upon which RodrĂguezâs seminal texts are otherwise based; and a critique of Althusserâs alleged historicism, which, while it scores some useful points, was less than attentive to the philosopherâs complexities. More damagingly, this same critique also fuelled the scurrilous distortions of Althusserâs work still circulating throughout the bourgeois academy and so threatens RodrĂguezâs own work with premature closure
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