29,279 research outputs found
Ray, David A., D.O.
No full textDr. Ray, a GP for the past 10 years in his hometown of Bridgeport, Texas is a member of TCOM’s first graduating class (1974). He served as the second president of the TCOM Alumni Association from 1975 to 1976.
Interviewed by C. Ray Stokes, August 6, 198
[A vase of roses in a sitting room with ceiling to floor moire curtains, silk wallpaper and glazed ceilings, ca. 1971] [transparency] /
No full textTitle devised by cataloguer from caption list and information in the publication: Australian decor.; Part of the Warren T. Harding and David C. Lorimer collection of interior design.; Similar image published in: Australian decor / Warren T. Harding [and] David C. Lorimer. Photos by David Beal. [Melbourne] : Nelson, [1971]; The photograph includes a Jean Isherwood and a Ray Crooke painting.; Also available in an electronic version via the Internet at: http://nla.gov.au/nla.pic-vn3314479. Photographer David Beal was employed by the firm Decor Associates Pty. Ltd. in whom Warren T. Harding and David C. Lorimer were partners, to photograph homes and business premises they had decorated. Some of these photographs were used in the publication: Australian decor / Warren T. Harding [and] David C. Lorimer. Photos by David Beal. [Melbourne] : Nelson, [1971]
[Sitting room with ceiling to floor moire curtains, silk wallpaper and glazed ceilings, ca. 1971] [transparency] /
No full textTitle devised by cataloguer from caption list and information in the publication: Australian decor.; Part of the Warren T. Harding and David C. Lorimer collection of interior design.; Similar image published in: Australian decor / Warren T. Harding [and] David C. Lorimer. Photos by David Beal. [Melbourne] : Nelson, [1971]; The photograph includes a Jean Isherwood and a Ray Crooke painting.; Also available in an electronic version via the Internet at: http://nla.gov.au/nla.pic-vn3314481. Photographer David Beal was employed by the firm Decor Associates Pty. Ltd. in whom Warren T. Harding and David C. Lorimer were partners, to photograph homes and business premises they had decorated. Some of these photographs were used in the publication: Australian decor / Warren T. Harding [and] David C. Lorimer. Photos by David Beal. [Melbourne] : Nelson, [1971]
Active X-ray optics for the next generation of X-ray space telescopes
No full textDescribed within is the design, manufacture, metrology and X-ray testing of an active X-ray
prototype intended for the next generation of X-ray telescopes. One of the challenges faced by
the X-ray telescope community is how to combine high resolution and high sensitivity into one
system, as weight limitations place constraints on the optics that can be launched. Therefore the
mandate of the active X-ray prototype is to provide high sensitivity through the ability of the optics
to be nested and to deliver high angular resolution through the active control of the optic’s form.
Piezoelectric unimorph actuators provide the active component: it is intended that they will correct
for figure errors within the optic and therefore increase the angular resolution capability.
The prototype’s design is based upon an ellipsoidal segment which provides point-to-point
focussing of an X-ray source. The prototype itself is composed of an electroformed nickel optic
where the non-reflective surface is populated with 30 piezoelectric actuators and it is the production
of the prototype that is the core of the presented research. Metrology of the actuators’ influence
functions is presented and highlight the prototype’s ability to deform its optic surface by microns.
In addition, the measured influence functions are compared against finite element models and a
distinct similarity between the functions is observed.
The prototype was tested at an X-ray beamline facility in November 2008 and the results
showed the prototype’s ability to correct the optic to achieve an improved angular resolution: from
0.786 arc-minutes to 0.686 arc-minutes in terms of full width half maximum. Finally, difficulties
in the manufacture of the prototype and X-ray testing shall be presented alongside future work in
conclusion to this thesis
Interview with Ray David Owen
No full textInterview with Ray Owen, Professor of Biology at Caltech, conducted by Rachel Prud'homme in 1983. The interview covers Owen's early life growing up in Wisconsin, where he attended the University of Wisconsin, studying cattle genetics with C. Stormont; his early research on chimerism in twin calves and on immunological tolerance. In 1946 he joins the biology division faculty at Caltech in genetics as a Gosney Fellow. Recollections of genetics at Caltech following World War II: concurrent arrivals include G. W. Beadle, N. Horowitz, H. Mitchell, and L. DuBridge. Recalls T. H. Morgan's reputation and his colleagues A. H. Sturtevant and S. Emerson. Other members of the biology division at this time include C. Bridges, H. J. Muller, H. Borsook, A. Haagen-Smit, C. Wiersma, A. van Harrevelt, and F. Went. Recollections of L. Pauling. His book, General Genetics, with A. Srb published in 1952. His work with D. Lindsley on bone marrow transplantation. At Caltech, involvement with freshman admissions. In 1961 becomes biology division chair. Discusses teaching and further work in student affairs, including admission and recruitment of women, the Committee on the Freshman Year, and pass/fail grading. Appointment in 1975 to dean of students and vice-president for student affairs. Involvement with National Cancer Program (1972-1975) and continuing research on immunological tolerance. Concludes with observations on genetic engineering and safety of genetics research
Ray, David B. III-107 HL 1417.
No full textMaterials related to Rev. William David Ray, pastor of First Baptist Church Lubbock c. 1960s
David Tobias Ray, Funeral service bulletin, April 6, 1985
No full textBulletin for the funeral service of David Tobias Ray held at Radcliffe Presbyterian Church in Atlanta, G.A. on April 6, 1985
Double-sided fresnel zone plates as high performance optics in X-ray microscopy
No full textX-ray microscopy describes a range of analytical techniques, specialized for the characterization of organic and inorganic samples using high energy photons. It takes advantage of the high penetration depth, high resolution and chemical sensitivity of X-rays and allows for the study of extended samples in their native environment without extensive sample preparation. Many of these experimental methods employ diffractive X-ray optics, like Fresnel zone plate lenses to obtain high spatial resolution or the better utilization of the incoming flux. Since improving the efficiency of zone plates can increase the throughput, quality and resolution of measurements, there is a constant demand for high efficiency and high resolution X-ray optics.
Stacking is an established concept for extending the capabilities of zone plate optics. By stacking two zone plates in each other's optical near field, they act as a single zone plate with combined optical transmission profile, that would be infeasible to make as a single optical element. Yet the existing implementations of stacking suffer from issues regarding complexity and stability.
This work presents the development of an alternative solution to conventional zone plate stacking, that circumvents most of its drawbacks. By patterning two zone plates on the front and back sides of a membrane, double-sided zone plates can deliver the advantages of stacked zone plates as inherently monolithic, single-chip optical elements.
Double-sided blazed zone plates with two complementary binary zone plates on the two sides of the membrane were produced to provide an effective four level transmission profile. This allowed to bypass the fundamental limitations of binary zone plates by providing up to 54.7% diffraction efficiency at 6.2 keV while having 200 nm smallest half-pitch and a reasonable working distance.
For high resolution zone plates, structure height is the main limiting factor. Therefore by patterning two identical zone plates on the two sides of the membrane, one can double the effective structure height. This provided us with a significant gain in focusing efficiency at high photon energies, as we have successfully measured 9.9% focusing efficiency at 9 keV with 30 nm smallest half-pitch, while preserving diffraction limited optical performance.
Stacking two complementary zone plates for multiplying their spatial frequencies opens the possibility for ultra-high resolution zone plate optics. We have successfully produced and tested interlaced zone plate optics down to 7 nm smallest half-pitch while still maintaining practical aperture sizes.
This thesis is a comprehensive summary of the work performed for the fabrication and characterization of the high performance zone plates representing each concept and provides possible examples for their future use
Cult: A Composite Novel
No full textCult (redacted)
The first component of the thesis is a composite novel called Cult which falls into two parts with seven narratives in each. Part 1 tracks the protagonist, Ellen, from her first involvement with the cult through to her eventually leaving it. Although fiction, the first half of the book answers the kinds of questions the author is asked when people discover that she was once a sannyasin (a follower of the guru Bhagwan Shree Rajneesh). While the experiences of meditation, group therapy and communal living are all faithfully rendered within the stories, the need for strong characters, narrative drive and a lightness of touch takes precedence.
Part 2 picks up Ellen’s story some twenty or so years later and explores what becomes of her in middle age. It also looks at other groups in society, such as academia, the law and the internet dating community which each have their own jargon, hierarchies, rituals and rules but are not considered to be cults.
The book examines the question raised in the Epigraph, ‘how do we be together when we feel so alone’ with a focus on relationships other than the familial and the romantic.
Collisions, Chasms and Connections: a Performative Exploration of the Composite Novel Form
The second part of the thesis is both a critical and creative response to three contemporary American books: Olive Kitteridge by Elizabeth Strout; A Visit from the Goon Squad by Jennifer Egan; and Legend of a Suicide by David Vann. The critical element comprises a close reading of the three books; a chronological reconstruction of their overarching storylines; and a consideration of what their authors have said about writing the books. It concludes that, in the composite novel, the simultaneous presentation of multiple views and storylines operate much like a 3D image to give the impression of depth to the characters and situations rendered. The creative element of the essay is a playful and personal response to the texts
X-Ray Waveguide Nanostructures - Design, Fabrication and Characterization
No full textTwo dimensionally confining x-ray channel waveguide structures are fabricated and used for the delivery of nanoscopic x-ray beams. The waveguides can be combined with a high gain Kirkpatrick-Baez-prefocusing mirror system yielding hard x-ray beams with a cross section down to 25 nm (full width at half maximum). The incoming synchrotron x-ray beam is coupled in from the front side of the waveguide. Here we address the general design of the x-ray optical devices and their fabrication by e-beam lithography methods. (c) 2007 American Institute of Physics
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