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Neutron-diffraction study of the solid layers at the liquid-solid boundary in 4He films adsorbed on graphite
(American Physical Society, 1981)
A neutron scattering study of the structure of 4He films adsorbed on graphite is reported. Diffraction from helium monolayers at a temperature of 1.2 K shows the formation of an incommensurate, triangular-lattice solid ...
Collective Excitations in Ethane Monolayers Adsorbed on Graphite (0001) Surfaces
(American Physical Society, 1984)
Inelastic incoherent neutron spectra below 4.1 THz have been obtained for the √3×4 "herringbone" and √3×√3 "on-end" monolayer phases of ethane adsorbed on graphite basal planes. One-phonon cross sections calculated ...
Technology for automated analysis of maize pollen used as a marker for mutation: 1. Flow-through systems
(National Institute of Environmental Health Sciences, 1981-01)
Maize pollen is used as a monitor for environmental pollutants. Mutant pollen grains (induced by environmental pollutants) are detectable above a background frequency of 5 or less in 10(5). To enumerate a satisfactory ...
Calculated effective Hamiltonian for La2CuO4 and solution in the impurity Anderson approximation
(American Physical Society, 1988)
We report local-density-functional calculations of hybridization matrix elements and effective electron-electron interactions in La2CuO4 defining a general effective Hamiltonian that we propose as an appropriate starting ...
Detection of the gravitomagnetic field using an orbiting superconducting gravity gradiometer. Theoretical principles
(American Physical Society, 1989)
The angular momentum of the Earth produces gravitomagnetic components of the Riemann curvature tensor, which are of the order of 10-10 of the Newtonian tidal terms arising from the mass of the Earth. These components could ...
Anomalous layering of Fe(CO)5 adsorbed on graphite
(American Physical Society, 1989)
Synchrotron x-ray diffraction experiments reveal the adsorption of iron pentacarbonyl [Fe(CO)5] on graphite basal-plane surfaces to be an extreme example of incomplete wetting in which only one solid layer of film coexists ...
Descartes on Theological Knowledge
(International Phenomenological Society, 1982)
Arnauld charged Descartes with circularity in his theological proof. I argue that Arnauld was correct. I also make suggestions about why Descartes fails to see the circularity. Both points are important. Many are uncomfortable ...
Performance-Based Teacher Evaluation in Missouri: A Three-Year Report
(1988)
The teacher performance evaluation, mandated in Missouri by a bill that legislators enacted during 1983, is a process for professional development through the identification and documentation of job related expectations ...
Audit of Principal Effectiveness: A User's Technical Manual. Designed and Tested for Principal Assessment in Elementary, Middle and Secondary Schools (Revised)
(1986)
This technical manual is presented to assist those using the Audit of Principal Effectiveness, an 80-statement evaluation instrument designed to determine teachers' perceptions of principals' effectiveness, allow principals ...
Audit of Principal Effectiveness: Instrumentation for Principalship Research-A Research Project Report
(1988-01)
Using the literature and research on principal effectiveness as a foundation, the Audit of Principal Effectiveness was developed. Initially, 162 items forming 12 theoretical factors describing effective principal behavior ...
Performance-Based Principal Evaluation in Missouri: A Three-Year Report
(1988)
The performance-based principal evaluation (PBPE), passed as a section of the 1985 Missouri Educational Reform Act, is a process for professional development of principals through the identification and documentation of ...
Principal Effectiveness in "National Recognition" Schools -- A Research Project Summary Report
(1989-07)
Between 1982 and 1987, 1,500 outstanding schools were recognized by the School Recognition Program, based on an analysis of their leadership, order and discipline, community support, and high standards and expectations for ...
Effects of hydrostatic pressure on the low-temperature photoluminescence spectrum of heavily doped CdS
(American Physical Society, 1985)
The photoluminescence spectrum of heavily doped CdS is studied under pressure at 300 and 6 K in a diamond anvil cell. The pressure-induced shift of the broad green luminescence peak at 300 K is found to depend on the ...
Photoluminescence studies of a GaAs-Ga1-xAlxAs superlattice at 8-300 K under hydrostatic pressure (0-70 kbar)
(American Physical Society, 1985)
The pressure dependence (0-70 kbar) of the photoluminescence spectra from a GaAs-Ga1-xAlxAs multiple-quantum-well (MQW) structure is reported at 8-300 K. The pressure coefficients of the EnhΓ and EnlΓ (n=1, 2) transitions ...
High-pressure studies of GaAs-Ga1-xAlxAs quantum wells of widths 26 to 150 Å
(American Physical Society, 1986)
Photoluminescence spectra of GaAs quantum wells of widths 26 to 150 Å are studied as a function of hydrostatic pressure (0-70 kbar) at 80 and 150 K. The pressure coefficients of both the heavy- and light-hole excitons are ...
High-pressure studies of GaAs-AlxGa1-xAs quantum wells at 300 and 80 K using photoreflectance spectroscopy
(American Physical Society, 1988)
A detailed photoreflectance study of a GaAs-Al0.3Ga0.7As multiple quantum well of well width 260 Å is carried out at 300 and 80 K. The pressure dependence of a large number of quantized states is observed. The sublinearity ...
Pressure studies of impurity levels in AlxGa1-xAs
(Institute of Physics, 1989)
The authors present a study of the deep and shallow donor levels under hydrostatic pressure. The shallow levels follow the conduction bands, while the deep levels are strongly sublinear with pressure. The temperature ...
Temperature dependence of the quantized states in a GaAs-Ga1-xAlxAs superlattice
(American Physical Society, 1988)
A detailed study of the photoreflectance spectra of a GaAs-Al0.3Ga0.7As superlattice as a function of temperature has revealed the temperature coefficients of the quantum- well transitions associated with the direct Γ ...
Multilayer structure of nitrogen adsorbed on graphite
(American Physical Society, 1989)
Elastic neutron diffraction has been used to study the structure and layering of nitrogen films adsorbed on the (002) surfaces of an exfoliated graphite substrate. The neutron-diffraction pattern of the fully compressed ...
Application of inelastic epithermal neutron scattering to the vibrational spectroscopy of adsorbed molecules: Butane physisorbed on graphite (0001) surfaces
(American Institute of Physics, 1984)
Inelastic epithermal neutron scattering (IENS) has been used to investigate the intramolecular vibrations of butane [CH3(CH2)2CH3] physisorbed on the (0001) surfaces of a graphite powder. The purpose of these studies was ...