14,045 research outputs found
Chalcogenide thin film materials for next generation data storage
No full textData can be stored in the form of amorphous and crystalline marks within a chalcogenide thin film. Commonly Ge2Sb2Te5 is used as the active data storage material to record these two different phases. Changes in phase are induced by controlled heating and cooling with laser radiation or an electric current. The research reported here shows, for the first time, that phase changes are possible in two new materials: BiSbTe and GaLaS. A further, known, phase change system, GeSbTe, has been used to test combinatorial deposition techniques and high throughput characterisation methodologies. An optical system, the static tester, was developed to test the time necessary for phase transitions. The system, capable of automated operation, can sequentially characterise the phase change kinetics of composition spread, thin film, samples. The GeSbTe system was investigated, as a function of composition, using combinatorial deposition methods. This showed that combinatorial methods can be applied to phase change materials and allowed new material characterisation over the whole ternary system. Using combinatorial methods, the electrical sheet resistance of the amorphous material is shown to be correlated to the tellurium concentration and is thought to be due to correlated increases in lone-pair defect charge trapping centres. The material’s resistivity can change by more than an order of magnitude by increasing the Te content from 20 at.% to 50 at.%. Conversely, in the amorphous phase, the refractive index was shown to decrease with increasing Te proportion and this has been related to a decrease in the material’s polarizability. The Sb:Te binary system has been doped with Bi using two different methods; sputter deposition from a composite target and using combinatorial, thermal evaporation deposition of elemental targets. New results have shown that Sb8Te2 can be doped with up to 13at.% Bi and still exist in a stable amorphous state. A novel chalcogenide material consisting of gallium, lanthanum and sulphur was shown, for the first time, to phase change. The crystallisation time of Ga:La:S:Cu material was found to be 150ns and dependent on the Cu proportion. Increasing the Cu by 30 at.% increased the crystallisation time to 350ns. The electrical resistivity of these materials was approximately 4Ωm. This allows efficient Joule heating and electrical switching was demonstrated. A finite element analysis has shown that this material can be amorphised with a current of just 0.4µA in comparison to 2.5mA required for a similar volume of Ge2Sb2Te5. Therefore Ga:La:S:Cu shows potential as a future electrical phase change data storage material
Barbara Simpson
No full textBarbara Simpson, daughter of Mr. and Mrs. Robert E. Simpson of Dutch John, announces her engagement and forthcoming marriage to Dennis L. Newhouse
Simpson Road, October 1967
No full textView of Simpson Road Northwest (now Joseph E. Boone Blvd) from a car
James K. Jordon, circa 1963
No full textJames K. Jordon (nephew of Robert E. Penn) in military uniform walks down the street in France.The Atlanta University Center Robert W. Woodruff Library acknowledges the generous support of the National Endowment for Humanities - Humanities Collections and Reference Resources Implementation Project Grant in supporting the processing and digitization of a number of its major archival collections as part of the project: Spreading the Word: Expanding Access to African American Religious Archival Collections at the Atlanta University Center Robert W. Woodruff Library.</em
Robert E. Penn Collection
No full textThis collection contains the photographs from the life and work of Reverend Robert E. Penn, a Baptist minister and educator. Penn was born in a rural coal mining town in West Virginia, and went on to receive degrees from Clark College, Gammon Theological Seminary, and Central Baptist Theological Seminary. He was a chaplain during World War II, and later after his pastoral work in Kansas City, Kansas, and Gary, Indiana, Penn returned to Atlanta to become Director of Field Education at the Interdenominational Theological Center in 1973. These photographs document Rev. Penns family life and friend in West Virginia, Indiana, and Georgia, as well as his work as Pastor of the First Baptist Church in Gary, Indiana, and Director of Field Education at the Interdenominational Theological Seminary.
At the AUC Robert W. Woodruff Library we are always striving to improve our digital collections. We welcome additional information about people, places, or events depicted in any of the works in this collection. To submit information, please contact us at [email protected].
The Influence of the Specification of Climate Change Damages on the Social Cost of Carbon
No full textDrawing upon climate change damage specifications previously proposed in the literature that the authors have calibrated to a common level of damages at 2.5°C, the authors examine the effect upon the social cost of carbon (SCC) of varying damage specifications in a DICE-like integrated assessment model. They find that SCC estimates are highly sensitive to uncertainty in extrapolating damages to high temperatures at moderate-to-high levels of risk aversion, but only modestly so at low levels of risk aversion. While in the absence of risk aversion, all of the SCC estimates but one agree within a factor of two, with a moderate level of risk aversion included, the differences among estimates grow greatly. For example, one composite damage specification, combining elements of different literature-derived specifications and roughly taking into account calibration uncertainty, yields SCC values 32% higher than the standard quadratic DICE damage function in the absence of risk aversion. With a coefficient of relative risk aversion of 1.4, however, the same uncertain specification yields SCC values almost triple those of the standard function. The authors conclude that failure to consider damages uncertainty and risk aversion jointly can lead to significant underestimation of the SCC.Peer reviewedThe published version of this article is found at: http://www.economics-ejournal.org/economics/journalarticles/2012-1
Robert McMillan Letter, MSS.1955
No full textAbstract: An 1861 letter to Governor Joseph E. Brown of Georgia from Robert McMillan discussing the organization of ten companies from Georgia, as well as copies of two additional letters written on the same piece of paper; one written by McMillan and the other by an unknown author, written to Senator Ira Foster.Scope and Content Note: This collection consists of a letter to Governor Joseph E. Brown of Georgia from Robert McMillan discussing the organization of ten companies from Georgia. Two additional letters are added to the first letter. One letter is also written by McMillan and discusses the need for guns for practice. The other is written by an unknown author and written to Senator Ira Foster. All letters are written on one piece of paper.Biographical/Historical Note: Robert McMillan was commanding colonel of Cobb's Brigade during the Civil War
The History of Early Denton Schools and Robert E. Lee School 1871-1957
No full textBooklet about the history of early Denton schools between 1871 and 1957, with an emphasis on the Robert E. Lee School
Emerging Trends and Technologies in the Information Ecosystem, December 10, 2021
No full textPresentation: "Trends in Collections and Analytics"and "Post-COVID Academic Library Trend-forecasting with a Focus on HBCUs"December’s Emerging Trends presentations provided tips on using technology for the creation and delivery of information. Madhu Kadiyala, Robert L. Fallen, Stephanie Bernard, and Suteera Apichatabutra share their knowledge from the Collections and Content Management Department, “Trends in Collections and Analytics.” There are many trends in the field of collections in the last few years. The whole serials market has been shaken up by mass cancellations, price changes, more document delivery choices, and changes in the way serials are used. Database products are transforming from collections of articles to “one stop shops” containing e-books, conference papers, videos, and many other publication formats. New analytics tools allow us to have detailed views of usage and complex views of collections. Open access materials are becoming better and more plentiful. The market is full of mergers and company acquisitions. “Collections as a service” is a fairly new buzz word, and there are recent cooperative collection projects that aim to preserve predictable numbers of copies of printed text as libraries move to more electronic delivery. In Jessica Epstein's presentation, "Post-COVID Academic Library Trend-Forecasting with a Focus on HBCUs," she covered topics ranging from the impact of access to a physical library space, issues of digital divide, device preferences during pandemic online learning and trend forecasting for Atlanta University Center Robert W. Woodruff Library
Oral History Interview: Robert Null
Full text linkThis interview is one of a series conducted concerning West Virginia communities, focusing on Ceredo. Mr. Robert Null discusses: various coaches (such as Paul Brown, Beau Shimbuckler, Thomas E. DanVule, Eli Camden Henderson, Carl Kenneth Ward, Guy Smith, Willis P. Peterson, Kenneth Dale Craycraft, Charlie Schneider, Stan Parish, Richard Tredway, & Tom Scott); football players (such as Frank Ward, Burt Ward, Ted Smith, Jeff Riffe, Stewart Way, Robert Alexander Morris, Jimmy Brown, Ernie Davis, Floyd Little, Piggy Varns, Vitto Regassi, Wally Reardon, Freddie Wyatt, Bruce Bosely, Sam Huff, & Mike Lewis); other individuals (such as Jimmy Hammer, Simpson Griffith, & Dick Griffith); coaching tactics; and other topics relating to football.https://mds.marshall.edu/oral_history/1302/thumbnail.jp
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