Thomas Gage letter to Andrew Simpson

Thomas Gage was commander-in-chief of British Forces in America from 1763 to 1775. This is a letter to Captain Andrew Simpson, 1769.https://digitalcommons.wofford.edu/littlejohnmss/1071/thumbnail.jp

Probing the Crystallization Process and Morphology of Thin Films of Yttrium Iron Garnet on Non-Garnet Substrates with in situ TEM Methods

University of Minnesota Ph.D. dissertation. October 2018. Major: Material Science and Engineering. Advisors: David Flannigan, Bethanie Stadler. 1 computer file (PDF); vii, 142 pages.Thin films of yttrium iron garnet (YIG) are of high interest for promising photonics and spintronics applications. Integration challenges with current silicon processing technology have limited device geometries and caused reduced performance largely arising from crystallization issues of as-deposited films. In order to gain understanding of the amorphous to crystalline phase transformation of YIG thin films on non-garnet substrates, plan-view TEM and in situ laser annealing TEM methods were utilized. Thin YIG films were sputtered onto SiO2 TEM window membranes. These films were initially annealed ex situ using standard RTA annealing methods. A nanocrystalline matrix phase between YIG crystallites was discovered where previous studies had reported uncrystallized material. Preliminary in situ laser annealing led to the serendipitous discovery of a 2-step rapid thermal anneal which improved garnet phase formation in the films. To investigate YIG crystallization kinetics on SiO2, temperature dependent in situ laser annealing TEM diffraction experiments were conducted. Avrami constants and apparent activation energy for the nanocrystalline phase formation is reported. In situ bright-field TEM was also used to investigate the growth of the YIG crystallites and indicated they enter a stress limited growth phase after reaching a critical dimension. Additionally, considerable effort was put into instrument development for in situ TEM methods, including optimization of single-shot pump probe capability. A range for optimized cathode to Wehnelt aperture distance and photoelectron inducing laser fluence are reported. Demonstrations of single-shot capabilities in both diffraction and imaging modes with current equipment are shown

Orbit transfer rocket engine integrated control and health monitoring system technology readiness assessment

The objectives of this task were to: (1) estimate the technology readiness of an integrated control and health monitoring (ICHM) system for the Aerojet 7500 lbF Orbit Transfer Vehicle engine preliminary design assuming space based operations; and (2) estimate the remaining cost to advance this technology to a NASA defined 'readiness level 6' by 1996 wherein the technology has been demonstrated with a system validation model in a simulated environment. The work was accomplished through the conduct of four subtasks. In subtask 1 the minimally required functions for the control and monitoring system was specified. The elements required to perform these functions were specified in Subtask 2. In Subtask 3, the technology readiness level of each element was assessed. Finally, in Subtask 4, the development cost and schedule requirements were estimated for bringing each element to 'readiness level 6'

The Chester Bulletin- September 8, 1892

The collection consists of individual issues of The Chester Bulletin a newspaper printed in Chester, South Carolina until 1899. The editors were Thomas W. Clawson, Jr. and George W. Gage. This issue scanned from microfilm is from September 8, 1892 (volume XIV, number 19).https://digitalcommons.winthrop.edu/chesterbulletin/1001/thumbnail.jp

The Chester Bulletin-September 1, 1882

The collection consists of individual issues of The Chester Bulletin a newspaper printed in Chester, South Carolina until 1899. The editors were Thomas W. Clawson, Jr. and George W. Gage. This issue scanned from microfilm is from September 1, 1882 (volume IV, number 22).https://digitalcommons.winthrop.edu/chesterbulletin/1000/thumbnail.jp

Optimized magneto-optical isolator designs inspired by seedlayer-free terbium iron garnets with opposite chirality

Simulations demonstrate that undoped yttrium iron garnet (YIG) seedlayers cause reduced Faraday rotation in silicon-on-insulator (SOI) waveguides with Ce-doped YIG claddings. Undoped seedlayers are required for the crystallization of the magneto-optical Ce:YIG claddings, but they diminish the interaction of the Ce:YIG with the guided modes. Therefore new magneto-optical garnets, terbium iron garnet (TIG) and bismuth-doped TIG (Bi:TIG), are introduced that can be integrated directly on Si and quartz substrates without seedlayers. The Faraday rotations of TIG and Bi:TIG films at 1550nm were measured to be +500 and -500°/cm, respectively. Simulations show that these new garnets have the potential to significantly mitigate the negative impact of the seedlayers under Ce:YIG claddings. The successful growth of TIG and Bi:TIG on low-index fused quartz inspired novel garnet-core waveguide isolator designs, simulated using finite difference time domain (FDTD) methods. These designs use alternating segments of positive and negative Faraday rotation for push-pull quasi phase matching in order to overcome birefringence in waveguides with rectangular cross-sections

The Chester Bulletin- August 27, 1896

The collection consists of individual issues of The Chester Bulletin a newspaper printed in Chester, South Carolina until 1899. The editors were Thomas W. Clawson, Jr. and George W. Gage. This issue scanned from microfilm is from August 27, 1896 (volume XVIII, number 25).https://digitalcommons.winthrop.edu/chesterbulletin/1002/thumbnail.jp

The Chester Bulletin- September 15, 1898

The collection consists of individual issues of The Chester Bulletin a newspaper printed in Chester, South Carolina until 1899. The editors were Thomas W. Clawson, Jr. and George W. Gage. This issue scanned from microfilm is from September 15, 1898 (volume XX, number is missing).https://digitalcommons.winthrop.edu/chesterbulletin/1003/thumbnail.jp

THE ROLE OF PREDATORS IN THE ECOLOGY, EPIDEMIOLOGY, AND SURVEILLANCE OF PLAGUE IN THE UNITED STATES

Predators play important roles in the ecology, epidemiology, and surveillance of plague in the United States. Most predators are accidental hosts of plague and, with the possible exception of grasshopper mice (Onychomys spp.), are not important sources of infection for feeding fleas. However, predators undoubtedly do play an important role in the natural cycle of plague by transporting infected fleas between different populations of plague-susceptible rodents. Predators are known to be at least accidental hosts for 40 of the 50 flea species that have been found to be naturally infected with plague in the U.S. Carnivores, including domestic cats, also play an important epidemiological role and have been sources of infection for 24 human plague cases since 1970. Serosurveillance of rodent-consuming carnivores is currently the most cost-effective method of monitoring plague in the western U.S. During the 1990s, these surveys have allowed CDC and other public health agencies to both identify plague risks for humans living in endemic regions and document the spread of plague into areas where it had not been identified previously