skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Optimization of a Strontium Aluminate


Strontium aluminate with Eu 2+ and Dy 3+ has been at the forefront of emerging applications for storage phosphors since its discovery in 1996. In this study, the emission intensity and luminescence lifetime of SrAl 2O 4: Eu 2+, Dy 3+ were enhanced by partial substitution of Ca 2+ into Sr 2+ sites in the matrix.

  1. Maryville College, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
OSTI Identifier:
DOE Contract Number:
Resource Type:
Country of Publication:
United States

Citation Formats

Bone, Alexandria N. Optimization of a Strontium Aluminate. United States: N. p., 2017. Web. doi:10.2172/1376499.
Bone, Alexandria N. Optimization of a Strontium Aluminate. United States. doi:10.2172/1376499.
Bone, Alexandria N. 2017. "Optimization of a Strontium Aluminate". United States. doi:10.2172/1376499.
title = {Optimization of a Strontium Aluminate},
author = {Bone, Alexandria N.},
abstractNote = {Strontium aluminate with Eu2+ and Dy3+ has been at the forefront of emerging applications for storage phosphors since its discovery in 1996. In this study, the emission intensity and luminescence lifetime of SrAl2O4: Eu2+, Dy3+ were enhanced by partial substitution of Ca2+ into Sr2+ sites in the matrix.},
doi = {10.2172/1376499},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month = 8

Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this thesis or dissertation.

Save / Share:
  • Extraction of aluminum from bauxite ore with caustic sodium hydroxide produces an alkaline waste termed bauxite residue. Methods of vegetating bauxite residue impoundments were investigated utilizing alkaline tolerant species with readily available organic amendments. Species screening experiments identified Distichlis spicata var. stricta, an alkaline tolerant grass, as a potential species for bauxite residue reclamation. Additions of sewage sludge to bauxite residue increased growth over 10-fold. Low yields were associated with high shoot tissue concentrations of Fe and Al, and low concentrations of Mg, K, P, Ca and N. In field experiments at a bauxite residue impoundment in Mobile, Alabama, organicmore » amendments (paper pulp waste, coastal bermuda grass mulch and sewage sludge) were tested as ameliorants to increase growth of Distichlis. In coarse textured bauxite residue amended with sewage sludge, a dense cover of Distichlis formed within 1.5 years. After 2.5 years, substantial declines in Distichlis cover occured. Additions of large quantities (6 cm) of sewage sludge to the surface of fine textured bauxite residue fostered growth of numerous local species. Most successful were Panicum dichotomiflorum and Cynodon dactylon. This research indicates the use of alkaline tolerant species with organic ameliorants has potential for bauxite residue reclamation. Problems with aluminum toxicity and Mn/sup 2 +/ deficiency must be overcome through additional research. The use of local, perhaps Al tolerant, species is also indicated if methods of effectively isolating roots from bauxite residue alkalinity are successful.« less
  • It was sought by means of an ion-exchange method to determine the nature and stability of the complexes of some poly- and metaphosphates with strontium. An investigation was made of the extent and course with time of the adsorption of Sr/sup 90/--Y/sup 90/ in 2 x 10/sup -7/ M soplution of ion strength 0.l5 on glass and polyethylene. Y00 was quantitatively adsorbed on glass from alkaline solution. In neutral solutions and on polyethylene the adsorption was less. The hydrolysis velocity of different phosphates in the presence of small amounts of strontium was carried out at 20 deg C at pHmore » 2.6 to 8.9. By means of the ion- exchange method, the strontium complexes of different phosphates were investigated using Sr/sup 85/ and Sr/sup 89/. Eight complexes were determined in a solution with an ion strength of 0.15 at pH 4 to 9 at 20 deg C, and their formation constants were calculated. These constants ranged from 0.2 to 8.74. (M.C.G.)« less
  • This work is the result of the application of nonlinear programming techniques to the optimization of engineering systems. There are two useful products resulting from this work. The first is a computer program, UKOPT, that optimizes power plants and coal conversion processes. It has been applied to, and developed using, advanced power generation concepts (combined cycles and cogeneration systems, for example) and coal conversion processes, often integrated with one another (e.g., integrated coal gasification combined cycles, AFBC based cycles). Hence, the program can be used for the design of power plants, or coal conversion processes integrated with power plants. However,more » since it uses a process simulator for evaluation of the performance measure being optimized, UKOPT can be used for optimizing any process that can be simulated on a process simulator, after appropriate modifications have been made. The second useful part of this work is a compilation of observations, experiences and guidelines for the optimization of engineering systems. These include studies on (1) the efficacy of various optimization methods when applied to process optimization; (2) handling discrete variables and discontinuous and inexact function values; (3) techniques for global optimization; (4) configuration optimization; (5) mathematical manipulations such as a scaling and penalty functions; and (6) techniques for reducing computation time. The program UKOPT incorporates most of the guidelines developed. The observations and guidelines comprising the second part of this work take on added significance because of their potential application to all engineering systems, whether they be power plants, electric circuits, chemical reactors, or systems requiring stress analysis. Some of these applications are demonstrated by means of examples.« less