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Elastic properties of monoclinic hafnium oxide

Description: The elastic properties of monoclinic hafnium oxide were studied as functions of porosity, temperature and grain size. An important finding of this study was that hafnium oxide is subject to microcracking when the grain size exceeds a critical value between 2 and 3 mu m. The behavior of the elastic moduli with porosity and temperature for crack-free hafnium oxide was typical for polycrystalline ceramics. The nature of the thermal expansion and the internal friction supported this finding. The el… more
Date: December 1, 1977
Creator: Dole, S.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Skull melting of synthetic minerals

Description: Direct high-frequency induction melting of dielectric materials in a water-cooled cage has been developed in the LASL synthetic minerals program. Molten material is contained in a skull, i.e., sintered shell, of its own composition so the traditional problems associated with refractory melt contamination are essentially eliminated. Preliminary analyses of power input, cage design, and coil geometry are discussed. Initial experimental results on the preparation of polycrystalline ingots, single … more
Date: December 1, 1977
Creator: Scott, S. D.; Hull, D. E. & Herrick, C. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis of monazite, zircon, and apatite from the southeastern Piedmont. National uranium resource evaluation program

Description: Two hundred sixty-three monazite, 191 zircon, and 16 apatite grains from 52 stream-sediment locations in the Southeastern Piedmont were analyzed by electron microprobe for one of the following suites of elements: Ca, La, Ce, Pr, Nd, Sm, Eu, Gd, Er, Dy, Y, Th, U, P, and F, or Ca, La, Ce, Fe, Er, Hf, Y, Th, U, P, Zr, Mg, Al, and Si. Monazite samples that had high uranium or thorium content and zircon samples that had high hafnium or iron content from a total of six locations were reanalyzed to co… more
Date: December 1, 1981
Creator: Karfunkel, B S; Fay, W M & Price, V Jr
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Extension of nuclear structure data base searches for gamma-ray laser candidates

Description: Results from a data base search of computerized nuclear structure libraries have been extended and augmented so as to expand the information available for nuclei suitable as gamma-ray laser candidates. The spectrum of nuclear levels occurring in deformed rotational nuclei have been calculated and have been used in conjunction with isomeric state data for odd-A systems. The results of this augmentation effort are presented with particular emphasis on results obtained for /sup 177/Lu, /sup 177/Hf… more
Date: December 1, 1987
Creator: Arthur, E. D.; Madland, D. G. & George, D. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Beryllium Use in the Advanced Test Reactor

Description: The Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) began operation in 1967. It makes use of a unique serpentine fuel core design and a beryllium reflector. Reactor control is achieved with rotating beryllium cylinders to which have been fastened plates of hafnium. Over time, the beryllium develops rather high helium content because of nuclear transmutations and begins to swell. The beryllium must be replaced at nominally 10-year intervals. Determination of when the replaceme… more
Date: December 1, 2007
Creator: Longhurst, Glen R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High Temperature Oxidation Behavior of gamma-Ni+gamma'-Ni3Al Alloys and Coatings Modified with Pt and Reactive Elements

Description: Materials for high-pressure turbine blades must be able to operate in the high-temperature gases (above 1000 C) emerging from the combustion chamber. Accordingly, the development of nickel-based superalloys has been constantly motivated by the need to have improved engine efficiency, reliability and service lifetime under the harsh conditions imposed by the turbine environment. However, the melting point of nickel (1455 C) provides a natural ceiling for the temperature capability of nickel-base… more
Date: December 1, 2007
Creator: Mu, Nan
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Study of radionuclides created by sup 181 Ta(. gamma. ,xn yp) reactions for bremsstrahlung photons produced by 150-MeV electrons

Description: Ten radionuclides, including isomers, from {sup 172}Ta to {sup 180}Ta and {sup 180m}Hf were produced by photon interactions with a sample of elemental tantalum and measured by counting photons using a high-resolution detection system. Relative yields of these radionuclides were obtained. In addition, precision half lives were obtained for {sup 175,176,180}Ta and {sup 180m}Hf. Those obtained for the three Ta isotopes agree with previously reported values. For {sup 180m}Hf, the present measuremen… more
Date: December 1, 1991
Creator: Miller, M.A. (Wisconsin Univ., River Falls, WI (United States)) & Dickens, J.K. (Oak Ridge National Lab., TN (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Grain boundary diffusion in oriented Ni sub 3 Al bicrystals containing boron

Description: The present research program entitled Grain Boundary Diffusion in Oriented Ni{sub 3}Al Bicrystals Containing Boron'' was granted to Lehigh University for a period of three years (September 1, 1986 to August 31, 1989). The work on grain boundary diffusion in Ni{sub 3}Al was partially completed. On the other hand, a number of new properties have been explored. Some additional efforts have been made on diffusion in newly discovered oxide superconductors.
Date: December 20, 1990
Creator: Chou, Y.T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Corrosion Study in the Chemical Air Separation (MOLTOX trademark ) Process

Description: This report presents the results of studies aimed at solving the corrosion problems encountered during operation of the MOLTOX{trademark} pilot plant. These studies concentrated on the screening of commercial and developmental alloys under conditions simulating operation conditions in this high temperature molten salt process. Process economic studies were preformed in parallel with the laboratory testing to ensure that an economically feasible solution would be achieved. In addition to the abo… more
Date: December 1, 1988
Creator: Kang, Doohee; Wong, Kai P.; Archer, R. A. & Cassano, A. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Laser conditioning and electronic defect measurements of HfO sub 2 and SiO sub 2 thin films

Description: Multilayer HfO{sub 2}/SiO{sub 2} high reflectors (HR) and polarizers show a permanent increase in their 1064-nm damage thresholds following laser conditioning at subthreshold fluences. Threshold increases of 2--3x are typical. In an effort to better understand the conditioning effect we have made laser conditioning and electronic property measurements on single layers of these two materials. The laser damage threshold of 1-{mu}m thick e-beam deposited SiO{sub 2} was increased by laser condition… more
Date: December 17, 1990
Creator: Kozlowski, M.R.; Staggs, M.; Rainer, F. (Lawrence Livermore National Lab., CA (USA)) & Stathis, J.H. (International Business Machines Corp., Yorktown Heights, NY (USA). Thomas J. Watson Research Center)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Experimental and theoretical studies on the C15 intermetallic compounds MV{sub 2} (M = Zr, Hf and Ta): Elasticity and phase stability

Description: The phase stability of C15 HfV{sub 2} was studied by specific heat measurements. The elastic constants of C15 HfV{sub 2} were measured by the resonant ultrasound spectroscopy. Total energy and electronic structure of C15 intermetallic compounds MV{sub 2} (M = Zr, Hf and Ta) were calculated using the linear muffin tin orbital (LMTO) method. The band structures at X-point near the Fermi level were used to understand the anomalous shear moduli of the C15 HfV{sub 2} and ZrV{sub 2}. It was found tha… more
Date: December 1, 1994
Creator: Chu, F.; Mitchell, T. E.; Chen, S. P.; Sob, M.; Siegl, R. & Pope, D. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The organometallic chemical vapor deposition of transition metal carbides: The use of homoleptic alkyls

Description: The organometallic chemical vapor deposition of transition metal carbides (M = Ti, Zr, Hf, and Cr) from tetraneopentyl-metal precursors has been carried out. Metal carbides can be deposited on Si, Al{sub 2}O{sub 3}, and stainless steel substrates from M[CH{sub 2}C(CH{sub 3}){sub 3}]{sub 4} at temperatures in the range of 300 to 750 C and pressures from 10{sup {minus}2} to 10{sup {minus}4} Torr. Thin films have also been grown using a carrier gas (Ar, H{sub 2}). The effects of variation of the m… more
Date: December 31, 1993
Creator: Healy, M. D.; Smith, D. C.; Springer, R. W.; Rubiano, R. R.; Springer, R. W. & Parmeter, J. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Study of radionuclides created by {sup 181}Ta({gamma},xn yp) reactions for bremsstrahlung photons produced by 150-MeV electrons

Description: Ten radionuclides, including isomers, from {sup 172}Ta to {sup 180}Ta and {sup 180m}Hf were produced by photon interactions with a sample of elemental tantalum and measured by counting photons using a high-resolution detection system. Relative yields of these radionuclides were obtained. In addition, precision half lives were obtained for {sup 175,176,180}Ta and {sup 180m}Hf. Those obtained for the three Ta isotopes agree with previously reported values. For {sup 180m}Hf, the present measuremen… more
Date: December 1, 1991
Creator: Miller, M. A. & Dickens, J. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

ORNL isotopic power fuels quarterly report for period ending September 30, 1973

Description: Heat soak periods were completed on four of the ten sets of compatibility couples which were put on test during the previous quarter. The four sets contain a total of 18 couples. Four couples were examined, and tests on the others are in progress. Examination of the Kilowatt Test Source capsule was completed. Four Cm/sup 203/ceramic couples were examined and additional tests are underway. Materials selection and test conditions were finalized for a 15-couple matrix to be initinted during FY 197… more
Date: December 1, 1973
Creator: Lamb, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Failure characterization of nodular defects in multi-layer dielectric coatings

Description: Nodular defects in multi-layer dielectric coatings have been computer modeled to characterize the electro-mechanical responses to laser pulses with wavelengths of 1.06 {mu}m and pulse lengths between 1 and 20 ns. The simulation begins with an axisymmetric electric field model using AMOS, a full-wave Maxwell solver with lossy (dispersive) electric and magnetic material models. Electric fields calculated by this code determine the spatial distribution of absorbed laser energy in the vicinity of t… more
Date: December 20, 1994
Creator: Sawicki, R. H.; Shang, C. C. & Swatloski, T. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Single-beam photothermal microscopy - a new diagnostic tool for optical materials

Description: A novel photothermal microscopy (PTM) is developed which uses only one laser beam, working as both the pump and the probe. The principle of this single-beam PTM is based on the detection of the second harmonic component of the laser modulated scattering (LMS) signal. This component has a linear dependence on the optical absorptance of the tested area and a quadratic dependence on the pump laser power. Using a pump laser at the wavelengths of 514.5- and 532-nm high-resolution photothermal scans … more
Date: December 22, 1998
Creator: Feit, M. D.; Kozlowski, M.; Natoli, J. Y.; Rubenchik, A. M.; Sheehan, L.; Wu, Z. L. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Trapping of hydrogen in Hf-based high κ dielectric thin films for advanced CMOS applications.

Description: In recent years, advanced high κ gate dielectrics are under serious consideration to replace SiO2 and SiON in semiconductor industry. Hafnium-based dielectrics such as hafnium oxides, oxynitrides and Hf-based silicates/nitrided silicates are emerging as some of the most promising alternatives to SiO2/SiON gate dielectrics in complementary metal oxide semiconductor (CMOS) devices. Extensive efforts have been taken to understand the effects of hydrogen impurities in semiconductors and its behavi… more
Date: December 2007
Creator: Ukirde, Vaishali
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Carbon Diffusion in the Group IVB and VB Transition Element Monocarbides

Description: New data were summarized for the diffusion of carbon in titanium, zirconium, hafnium, vanadium, niobium, and tantalum monocarbides which were measured over temperature ranges overlapping between 1700 to 3000 degrees Celsius.
Date: December 1, 1965
Creator: Tobin, J. M.; Adelsberg, L. M.; Cadoff, L. H. & Brizes, W. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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