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• 2701. [Article] Precision measurements of the Mössbauer fraction of Fe⁵⁷ in Pt, Pd and Cu

  Precision measurements of the Mössbauer fraction of the 14.4 kev Fe⁵⁷ transition were made using the black, wide absorber technique. The Fe⁵⁷ was diffused, as a dilute Mössbauer impurity, into 99.995% ...

  Citation × Citation Citation Abstract Copy Title: Precision measurements of the Mössbauer fraction of Fe⁵⁷ in Pt, Pd and Cu Author: Nees, Wilbur Lee Year: 1968 Precision measurements of the Mössbauer fraction of the 14.4 kev Fe⁵⁷ transition were made using the black, wide absorber technique. The Fe⁵⁷ was diffused, as a dilute Mössbauer impurity, into 99.995% purity single crystal chips of Pt, Pd and Cu. By comparing the Debye form of -ln f, corrected for anharmonicity, with our data, we extracted a high and low temperature Debye theta, as well as an anharmonicity coefficient, є, for the three materials. We estimated the accuracy of our data to be ± 1%. From the data we concluded that the Fe⁵⁷ in Cu has stronger force constants and is more anharmonic than pure Cu, while Fe⁵⁷ in Pt and Pd has smaller force constants and about the same anharmonicity as the pure host materials. Title: Precision measurements of the Mössbauer fraction of Fe⁵⁷ in Pt, Pd and Cu Author: Nees, Wilbur Lee Year: 1968 Precision measurements of the Mössbauer fraction of the 14.4 kev Fe⁵⁷ transition were made using the black, wide absorber technique. The Fe⁵⁷ was diffused, as a dilute Mössbauer impurity, into 99.995% purity single crystal chips of Pt, Pd and Cu. By comparing the Debye form of -ln f, corrected for anharmonicity, with our data, we extracted a high and low temperature Debye theta, as well as an anharmonicity coefficient, є, for the three materials. We estimated the accuracy of our data to be ± 1%. From the data we concluded that the Fe⁵⁷ in Cu has stronger force constants and is more anharmonic than pure Cu, while Fe⁵⁷ in Pt and Pd has smaller force constants and about the same anharmonicity as the pure host materials. Close

• 2702. [Article] Bi-Material Assembly Subjected to Thermal Stress: Propensity to Delamination Assessed Using Interfacial Compliance Model

  It is shown that an engineering stress model suggested about 30 years ago for the approximate evaluation of the interfacial stresses in adhesively bonded or soldered bi-material assemblies experiencing ...

  Citation × Citation Citation Abstract Copy Title: Bi-Material Assembly Subjected to Thermal Stress: Propensity to Delamination Assessed Using Interfacial Compliance Model Author: Suhir, Ephraim Year: 2016 It is shown that an engineering stress model suggested about 30 years ago for the approximate evaluation of the interfacial stresses in adhesively bonded or soldered bi-material assemblies experiencing thermal loading and based on the concept of interfacial compliance can be employed also for the assessment of the assembly’s propensity to delamination. The analysis is limited to the shearing mode of failure and to the elastic stresses. A probabilistic extreme value distribution (EVD) approach can be used to consider the random nature of both the actual and the critical stress-energy-release-rates (SERR). The step-wise nature of the typical failure oriented accelerated test (FOAT) loading in the electronics reliability field (such as, e.g., temperature cycling) is addressed. The general concepts are illustrated by numerical examples. Title: Bi-Material Assembly Subjected to Thermal Stress: Propensity to Delamination Assessed Using Interfacial Compliance Model Author: Suhir, Ephraim Year: 2016 It is shown that an engineering stress model suggested about 30 years ago for the approximate evaluation of the interfacial stresses in adhesively bonded or soldered bi-material assemblies experiencing thermal loading and based on the concept of interfacial compliance can be employed also for the assessment of the assembly’s propensity to delamination. The analysis is limited to the shearing mode of failure and to the elastic stresses. A probabilistic extreme value distribution (EVD) approach can be used to consider the random nature of both the actual and the critical stress-energy-release-rates (SERR). The step-wise nature of the typical failure oriented accelerated test (FOAT) loading in the electronics reliability field (such as, e.g., temperature cycling) is addressed. The general concepts are illustrated by numerical examples. Close

• 2703. [Article] Remote Plasma Assisted Growth of Graphene Films

  Single and multiple layers of graphene films were grown on 111 oriented single crystals of nickel and polycrystalline nickel films using remote plasma assisted chemical vapor deposition. Remote plasma ...

  Citation × Citation Citation Abstract Copy Title: Remote Plasma Assisted Growth of Graphene Films Author: Nandamuri, Gopichand, Roumimov, Sergei, Solanki, Raj Year: 2010 Single and multiple layers of graphene films were grown on 111 oriented single crystals of nickel and polycrystalline nickel films using remote plasma assisted chemical vapor deposition. Remote plasma was employed to eliminate the effect of the plasma electrical field on the orientation of the grown graphene films, as well as to reduce the growth temperature compared to conventional chemical vapor deposition. The electrical and optical properties, including high resolution transmission electron microscopy of these films, suggest that this approach is both versatile and scalable for potential large area optoelectronic applications. Title: Remote Plasma Assisted Growth of Graphene Films Author: Nandamuri, Gopichand, Roumimov, Sergei, Solanki, Raj Year: 2010 Single and multiple layers of graphene films were grown on 111 oriented single crystals of nickel and polycrystalline nickel films using remote plasma assisted chemical vapor deposition. Remote plasma was employed to eliminate the effect of the plasma electrical field on the orientation of the grown graphene films, as well as to reduce the growth temperature compared to conventional chemical vapor deposition. The electrical and optical properties, including high resolution transmission electron microscopy of these films, suggest that this approach is both versatile and scalable for potential large area optoelectronic applications. Close

• 2704. [Article] Influence of light on algal growth in the lower Willamette River

  During the summer of 1974 chemical conditions in the lower reaches of the Willamette River, Oregon were similar to those in other rivers currently experiencing nuisance algal growth problems. Temperature ...

  Citation × Citation Citation Abstract Copy Title: Influence of light on algal growth in the lower Willamette River Author: Wille, Stephen Arthur Year: 1976 During the summer of 1974 chemical conditions in the lower reaches of the Willamette River, Oregon were similar to those in other rivers currently experiencing nuisance algal growth problems. Temperature and chemical nutrients are not limiting. Relatively high populations of phytoplankton and productivity values for upstream periphyton beds and surface waters suggest moderately eutrophic conditions. However, with increased depth in the lower river, and a constant euphotic zone, the amount of photosynthetically available light is reduced. With sufficient depth and complete mixing the critical depth is exceeded. Primary productivity rates are subsequently limited by low light availability in the lower river. Title: Influence of light on algal growth in the lower Willamette River Author: Wille, Stephen Arthur Year: 1976 During the summer of 1974 chemical conditions in the lower reaches of the Willamette River, Oregon were similar to those in other rivers currently experiencing nuisance algal growth problems. Temperature and chemical nutrients are not limiting. Relatively high populations of phytoplankton and productivity values for upstream periphyton beds and surface waters suggest moderately eutrophic conditions. However, with increased depth in the lower river, and a constant euphotic zone, the amount of photosynthetically available light is reduced. With sufficient depth and complete mixing the critical depth is exceeded. Primary productivity rates are subsequently limited by low light availability in the lower river. Close

• 2705. [Article] Anisotropic magnetoresistance in the organic superconductor β″–(BEDT-TTF)2SF5CH2CF2SO3

  In this paper, we report transport measurements of interlayer magnetoresistance with field parallel and perpendicular to the current direction in an all organic superconductor β″–(BEDT-TTF)₂SF₅CH₂CF₂SO₃. ...

  Citation × Citation Citation Abstract Copy Title: Anisotropic magnetoresistance in the organic superconductor β″–(BEDT-TTF)2SF5CH2CF2SO3 Author: Su, X., Zuo, F., Schlueter, J. A., Williams, Jack M., Nixon, P. G., Winter, Rolf Walter, Gard, Gary L. Year: 1999 In this paper, we report transport measurements of interlayer magnetoresistance with field parallel and perpendicular to the current direction in an all organic superconductor β″–(BEDT-TTF)₂SF₅CH₂CF₂SO₃. For H∥I, the isothermal magnetoresistance R(H) at low temperatures (T Title: Anisotropic magnetoresistance in the organic superconductor β″–(BEDT-TTF)2SF5CH2CF2SO3 Author: Su, X., Zuo, F., Schlueter, J. A., Williams, Jack M., Nixon, P. G., Winter, Rolf Walter, Gard, Gary L. Year: 1999 In this paper, we report transport measurements of interlayer magnetoresistance with field parallel and perpendicular to the current direction in an all organic superconductor β″–(BEDT-TTF)₂SF₅CH₂CF₂SO₃. For H∥I, the isothermal magnetoresistance R(H) at low temperatures (T Close

• 2706. [Article] Flight Test of Pacific Spaceflight Pressure Garment Mark II in Bell 206 Jet Ranger

  Pacific Spaceflight’s Mark II pressure garment (model Gagarin) was test flown to 17,200 feet MSL (5,242m) while worn and operated by Dr. C.M. Smith. The garment and its portable life support system (PLSS) ...

  Citation × Citation Citation Abstract Copy Title: Flight Test of Pacific Spaceflight Pressure Garment Mark II in Bell 206 Jet Ranger Author: Smith, Cameron M. Year: 2014 Pacific Spaceflight’s Mark II pressure garment (model Gagarin) was test flown to 17,200 feet MSL (5,242m) while worn and operated by Dr. C.M. Smith. The garment and its portable life support system (PLSS) maintained appropriate pressure, temperature and carbon dioxide levels throughout the 47-minute flight. The suit also provided sufficient elbow mobility, due to its convolute joints, for the suited person to operate the portable life support system’s manual suit pressure setting valve and the hand-held radio. Title: Flight Test of Pacific Spaceflight Pressure Garment Mark II in Bell 206 Jet Ranger Author: Smith, Cameron M. Year: 2014 Pacific Spaceflight’s Mark II pressure garment (model Gagarin) was test flown to 17,200 feet MSL (5,242m) while worn and operated by Dr. C.M. Smith. The garment and its portable life support system (PLSS) maintained appropriate pressure, temperature and carbon dioxide levels throughout the 47-minute flight. The suit also provided sufficient elbow mobility, due to its convolute joints, for the suited person to operate the portable life support system’s manual suit pressure setting valve and the hand-held radio. Close

• 2707. [Article] Thermal hysteresis in acoustic resonators

  In some applications of piezoelectrically driven acoustic resonators, the power dissipated in the resonating material may be sufficient to significantly change the temperature and hence the resonance frequency. ...

  Citation × Citation Citation Abstract Copy Title: Thermal hysteresis in acoustic resonators Author: Casperson, Lee W., Davis, Lloyd M., Harvey, John D. Year: 1982 In some applications of piezoelectrically driven acoustic resonators, the power dissipated in the resonating material may be sufficient to significantly change the temperature and hence the resonance frequency. A straightforward analysis shows that this effect can lead to severe hysteresis and thermal bistability. This model is in agreement with experiments that have been performed using a fused silica acousto‐optic modulator. Title: Thermal hysteresis in acoustic resonators Author: Casperson, Lee W., Davis, Lloyd M., Harvey, John D. Year: 1982 In some applications of piezoelectrically driven acoustic resonators, the power dissipated in the resonating material may be sufficient to significantly change the temperature and hence the resonance frequency. A straightforward analysis shows that this effect can lead to severe hysteresis and thermal bistability. This model is in agreement with experiments that have been performed using a fused silica acousto‐optic modulator. Close

• 2708. [Article] Transmission studies of explosive vaporization of a transparent liquid film on an opaque solid surface induced by excimer-laser-pulsed irradiation

  Examines the dynamics of the explosion of a liquid film by an ultraviolet excimer pulsed laser studied experimentally on top of an amorphous silicon film deposited on fused quartz. Background on thermal ...

  Citation × Citation Citation Abstract Copy Title: Transmission studies of explosive vaporization of a transparent liquid film on an opaque solid surface induced by excimer-laser-pulsed irradiation Author: Leung, P.T., Do, Nhan, Klees, Leander, Leung, Wing P., Tong, Frank Year: 1992 Examines the dynamics of the explosion of a liquid film by an ultraviolet excimer pulsed laser studied experimentally on top of an amorphous silicon film deposited on fused quartz. Background on thermal physics of superheated pure or mixed liquids; Techniques for surface temperature measurement; Experimental of probe laser and pulsed excimer laser. Title: Transmission studies of explosive vaporization of a transparent liquid film on an opaque solid surface induced by excimer-laser-pulsed irradiation Author: Leung, P.T., Do, Nhan, Klees, Leander, Leung, Wing P., Tong, Frank Year: 1992 Examines the dynamics of the explosion of a liquid film by an ultraviolet excimer pulsed laser studied experimentally on top of an amorphous silicon film deposited on fused quartz. Background on thermal physics of superheated pure or mixed liquids; Techniques for surface temperature measurement; Experimental of probe laser and pulsed excimer laser. Close

• 2709. [Article] Residual images in charged-coupled device detectors

  We present results of a systematic study of persistent, or residual, images that occur in charged-coupled device (CCD) detectors. A phenomenological model for these residual images, also known as "ghosting," ...

  Citation × Citation Citation Abstract Copy Title: Residual images in charged-coupled device detectors Author: Rest, Armin, Mündermann, Lars, Widenhorn, Ralf, Bodegom, Erik, McGlinn, T. C. Year: 2002 We present results of a systematic study of persistent, or residual, images that occur in charged-coupled device (CCD) detectors. A phenomenological model for these residual images, also known as "ghosting," is introduced. This model relates the excess dark current in a CCD after exposure to the number of filled impurity sites which is tested for various temperatures and exposure times. We experimentally derive values for the cross section, density, and characteristic energy of the impurity sites responsible for the residual images. Title: Residual images in charged-coupled device detectors Author: Rest, Armin, Mündermann, Lars, Widenhorn, Ralf, Bodegom, Erik, McGlinn, T. C. Year: 2002 We present results of a systematic study of persistent, or residual, images that occur in charged-coupled device (CCD) detectors. A phenomenological model for these residual images, also known as "ghosting," is introduced. This model relates the excess dark current in a CCD after exposure to the number of filled impurity sites which is tested for various temperatures and exposure times. We experimentally derive values for the cross section, density, and characteristic energy of the impurity sites responsible for the residual images. Close

• 2710. [Article] On the Production of the Positive Antihydrogen Ion H̄+ via Radiative Attachment

  We provide an estimate of the cross section for the radiative attachment of a second positron into the state of the ion using Ohmura and Ohmura's (1960 Phys. Rev. 118 154) effective range theory and the ...

  Citation × Citation Citation Abstract Copy Title: On the Production of the Positive Antihydrogen Ion H̄+ via Radiative Attachment Author: Keating, Chris M., Charlton, M., Straton, Jack C. Year: 2014 We provide an estimate of the cross section for the radiative attachment of a second positron into the state of the ion using Ohmura and Ohmura's (1960 Phys. Rev. 118 154) effective range theory and the principle of detailed balance. The ion can potentially be created using interactions of positrons with trapped antihydrogen, and our analysis includes a discussion in which estimates of production rates are given. Motivations to produce include its potential use as an intermediary to cool antihydrogen to ultra-cold (sub-mK) temperatures for a variety of studies, including spectroscopy and probing the gravitational interaction of the anti-atom. Title: On the Production of the Positive Antihydrogen Ion H̄+ via Radiative Attachment Author: Keating, Chris M., Charlton, M., Straton, Jack C. Year: 2014 We provide an estimate of the cross section for the radiative attachment of a second positron into the state of the ion using Ohmura and Ohmura's (1960 Phys. Rev. 118 154) effective range theory and the principle of detailed balance. The ion can potentially be created using interactions of positrons with trapped antihydrogen, and our analysis includes a discussion in which estimates of production rates are given. Motivations to produce include its potential use as an intermediary to cool antihydrogen to ultra-cold (sub-mK) temperatures for a variety of studies, including spectroscopy and probing the gravitational interaction of the anti-atom. Close