Now showing items 141-150 of 177
Phase separation during film growth
(The American Institute of Physics, 1992-07-15)
A diffusion equation describing phase separation during co‐deposition of a binary alloy is derived, and solved in the limit of dominant surface diffusion. Linear stability analysis yields results similar to bulk spinodal ...
Thermodynamic properties of metastable Ag‐Cu alloys
(The American Institute of Physics, 1993-09-01)
The enthalpies of formation of metastable fcc Ag‐Cu solid solutions, produced by ball milling of elemental powders, were determined by differential scanning calorimetry. Experimental thermodynamic data for these metastable ...
Charge calibration of CsI(Tl)/photodiode spectroscopy systems
(Elsevier, 1992-04-01)
A charge calibration method for spectroscopy systems that use inorganic scintillators, photodiodes, and charge-sensitive preamplifiers is presented. The shaped square wave (SSW) method accounts for ballistic deficit when ...
Existence and Uniqueness Theorems for the Neutron Transport Equation
(The American Institute of Physics, 1963-11)
In an attempt to understand the conditions under which the neutron transport equation has solutions, and the properties of those solutions, a number of existence and uniqueness theorems are proved. One finds that the ...
Evidence for field enhanced electron capture by EL2 centers in semi‐insulating GaAs and the effect on GaAs radiation detectors
(The American Institute of Physics, 1994-06-15)
The performance of Schottky contact semiconductor radiation detectors fabricated from semi‐insulating GaAs is highly sensitive to charged impurities and defects in the material. The observed behavior of semi‐insulating ...
Transition from lateral to transverse phase separation during film co‐deposition
(The American Institute of Physics, 1991-11-11)
We report observations of two distinct types of phase‐separated microstructures in co‐deposited Al‐Ge films. In the initial stages of growth, lateral phase separation is observed, with a temperature dependence consistent ...
Time‐Dependent One‐Speed Albedo Problem for a Semi‐Infinite Medium
(The American Institute of Physics, 1965-07)
A Laplace transformation technique is used to determine the neutron distribution in a semi‐infinite medium which has been irradiated by a neutron pulse. The result is given in terms of known solutions of Milne's problem ...
Evaluation of wavelength shifters for spectral separation of barium fluoride emissions
(Elsevier, 1994-08-21)
Application of the barium fluoride (BaF2) scintillator for characterization of intense radiation fields has been pursued since the fast component was discovered in the early 1980's. Unfortunately, ~ 80% of the scintillator ...
Direct measurement of k o for monitor neutron activation analysis
(Kluwer Academic Publishers; Akadémiai Kiadó ; Springer Science+Business Media, 1994-03)
This paper introduces the thermal column or the cold neutron guide beam of the 20 MW NBSR at the National Institute of Standards and Technology as a direct k o measurement facility. Measurement of k o at this facility not ...