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Adaptation of a Commercial Counter X-Ray Diffractometer for Investigations to 3000°C

Description: The rapid advances in many technologically important areas have not only served to accentuate the increased demands for high temperature metals and ceramics but have necessitated a more through knowledge of their physical properties when exposed to high temperature service. Toward this latter end, the use of X-ray diffraction has proved an invaluable tool in providing data of regions of thermal stability, expansion coefficients, solid solubility limits, and phase transformations by direct exami… more
Date: March 12, 1963
Creator: LaPalca, Samuel; Farber, Gerald & Adler, George
Partner: UNT Libraries Government Documents Department
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Cell Population Kinetics of an Osteogenetic Tissue, I

Description: Cell proliferation on the actively growing periosteal surface of the femur of rabbits aged two weeks, has been investigated using autoradiographic techniques. Injections of tritiated glycine and tritiated thymidine were given simultaneously and the animals sacrificed at intervals from one hour to 5 days after injection. The glycine labelled the position of the bone surface at the time of injection and the thymidine labelled the cells which were synthesizing DNA . The rate of increase in the cel… more
Date: March 12, 1963
Creator: Maureen, Owen
Partner: UNT Libraries Government Documents Department
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Cell Population Kinetics of an Osteogenetic Tissue, II

Description: A study of the cell kinetics on the actively growing periosteal surface of the femur of rabbits ages two weeks has been continues. A single injection of tritiated thymidine was given and the rabbits killed from one hour to four days after injection. The grain count spectra of the different cell types, pre-osteoblast, osteoblast and osteocyte, have been compared at different times after injection. The results showed evidence for the uptake of thymidine in nuclei which is not associated with cell… more
Date: March 12, 1963
Creator: Owen, Maureen & Pherson, Sheila Mac
Partner: UNT Libraries Government Documents Department
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Four Short Articles on Genetics of Maize

Description: Studies carried on since 1956 indicate that the prosaic breeding procedure of sibbing among the most perennial segregates in the hybrid of 4n maize x 4n perennial teosinte quickly restores perennialism to 50% maize tetraploids through increasing the expression of the rhizomatous habit under selection pressure. Similarly, only two generations of selection at the 75% maize level have resulted in a progressive recovery of the perennial expressive. A high degree of maize-likeness therefore appears … more
Date: March 12, 1963
Creator: Brookhaven National Laboratory
Partner: UNT Libraries Government Documents Department
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Linkage in Autotetraploids and Allotetraploids of Zea

Description: Studies of linkage in polyploids have been exceedingly rare. Only three previous studies of linkage in autotetraploid maize have been reported. Murray (1944), in a limited analysis of crossing over among 4 linked markers in chromosome 2, found varying degree of difference in linkage values between 2n and 4n maize in the three interposed segments. Dempsey (1956) found linkage values wx - c region of chromosome 9 to correspond closely between autotetraploid and diploid maize. More recently Welch … more
Date: March 12, 1963
Creator: Shaver, Donald L.
Partner: UNT Libraries Government Documents Department
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Mathematics of Intermittent Irradiation

Description: Initiation of reactions by intermittent irradiation is frequently encountered in physical, chemical, and biological systems. Mathematical expressions for transient and steady state concentrations of reactive species in these systems are useful for predicting performance and for research purposes. A general method of formulation of the intermittent irradiation problem is presented herein, and illustrative solutions are obtained for radioactive decay chains and for the rotating sector method.
Date: March 12, 1963
Creator: Hill, F. B.
Partner: UNT Libraries Government Documents Department
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Study of Low Frequency Molecular Motions in HF, KHF2, KH2F3 and NaH2F3

Description: The spectra of KHF2, KH2F3, NaH2F3, liquid and solid HF were measured between 1200 and 30 cm-1 by the inelastic scattering of "cold neutrons" (0.005e.v.). The spectrum of KHF2 is in agreement with previous infrared measurements and shows a peak at 147 mV corresponding to a deformation frequency v2 of the F-H-F group and a broad peak at 13 mV due to a libration of this group. The observed spectra for KH2F3, NaH2F3 solid and liquid HF were compared with that for KHF2 considering the known results… more
Date: March 12, 1963
Creator: Boutin, Henri & Safford, G. J.
Partner: UNT Libraries Government Documents Department
open access

Ytterbium and Terbium Dodecaborides

Description: The synthesis of several rare earth dodecaborides, isomorphous with UB12 and ZrB12, and crystallographic data for these phases were reported recently. The unit cells are face centered cubic with four formula weights of MeB12 per unit cell; the structures may be visualized in terms of boron atoms linked in a rigid three-dimensional network, with the metal atoms in large cubo-octahedral holes.
Date: March 12, 1963
Creator: La Placa, Sam & Noonan, Daniel
Partner: UNT Libraries Government Documents Department
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