Evaluation of Carbagel Process for Air Refrigeration for Use With BNL Reactor (open access)

Evaluation of Carbagel Process for Air Refrigeration for Use With BNL Reactor

Technical report outlining the use of the Carbagel process in nuclear reactors, its technical feasibility, and case studies of the Carbagel process and its theoretical and technical use for reactors such as the Brookhaven National Laboratory reactor.
Date: April 12, 1950
Creator: Winsche, W. E.
System: The UNT Digital Library
Cell Population Kinetics of an Osteogenetic Tissue, I (open access)

Cell Population Kinetics of an Osteogenetic Tissue, I

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 cell population was determined by counting the number of cells beyond the glycine label at different times after injection. The cell kinetics of the fibroblast--pre-osteoblast--osteoblast--osteocyte system has been studied. The fibroblasts are relatively unimportant from the point of view of increase in the cell population. The main site of cell proliferation is the layer of preosteoblasts on the periosteal surface. The rate of movement of cells from the pre-osteoblast to the osteoblast and osteocyte compartments has been measured. The incorporation of osteoblasts into the bone is not a random process, but it appears that the osteoblast must spend a certain time on the periosteal surface before becoming either an osteocyte or a relatively inactive osteoblast lining a haversian canal. During its most active …
Date: March 12, 1963
Creator: Maureen, Owen
System: The UNT Digital Library
Cell Population Kinetics of an Osteogenetic Tissue, II (open access)

Cell Population Kinetics of an Osteogenetic Tissue, II

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 division. A small percentage of osteoblasts was initially labelled at one hour and there was evidence that the majority of these had not divided by 3 or 4 days after injection. Some thymidine labelled cells had also become osteocytes without division. Furthermore, it appeared that a considerable fraction of the initially labelled pre-osteoblasts did not divide. The S-period for the pre-osteoblasts and osteoblasts was measured using a double-labelled thymidine technique.
Date: March 12, 1963
Creator: Owen, Maureen & Pherson, Sheila Mac
System: The UNT Digital Library
Study of Low Frequency Molecular Motions in HF, KHF2, KH2F3 and NaH2F3 (open access)

Study of Low Frequency Molecular Motions in HF, KHF2, KH2F3 and NaH2F3

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 that the F-F distance increases, the position of the H atom between the two fluorines becomes more asymmetrical, and the strength of the hydrogen bond decreases in going from the HF2- ion to H2F3- ion to HF. In this comparison the known structure of the H2F3- ion is considered as being intermediate between that of HF2- and the zig-zag hydrogen bonded chains in solid HF. As a result, the lines observed at 112 mV and 67 mV in the H2F3- spectra and in HF respectively are associated with the deformation frequency v2 of the H-F-H group in these compounds. In addition the spectra of H2F3- ions show a peak at a 15 mV …
Date: March 12, 1963
Creator: Boutin, Henri & Safford, G. J.
System: The UNT Digital Library
Adaptation of a Commercial Counter X-Ray Diffractometer for Investigations to 3000°C (open access)

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

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 examination at temperature. Since this Laboratory has for some time now been engaged in the study of refractory nuclear materials, it was thought desirable to employ and possibly extend this technique to temperatures ranging up to 3000°C. This communication will describe the equipment developed for this purpose, with experimental results to be described in subsequent publications.
Date: March 12, 1963
Creator: LaPalca, Samuel; Farber, Gerald & Adler, George
System: The UNT Digital Library
Mathematics of Intermittent Irradiation (open access)

Mathematics of Intermittent Irradiation

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.
System: The UNT Digital Library
Four Short Articles on Genetics of Maize (open access)

Four Short Articles on Genetics of Maize

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 to be compatible with the perennial expression at the 4n level.
Date: March 12, 1963
Creator: Brookhaven National Laboratory
System: The UNT Digital Library
Linkage in Autotetraploids and Allotetraploids of Zea (open access)

Linkage in Autotetraploids and Allotetraploids of Zea

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 (1962), in a more extensive analysis of linkage among the same group of chromosome 2 markers studied earlier by Murray, concluded that although individual progenies varied, linkage values in diploid and tetraploid maize, with some exceptions, are similar. Limited data from one segment of the allotetraploid of perennial teosinte x maize (Emerson and Beadle 1932) probably represent the only reported linkage tabulation in this type of polyploid. A further study of linkage of Zea polyploids seemed worthwhile because of the increasing practical importance of polyploids, of the possibility of adding to fundamental knowledge of tetraploid cytology and genetics, and of the bearing such work may have upon the question of the taxonomic affinities of maize.
Date: March 12, 1963
Creator: Shaver, Donald L.
System: The UNT Digital Library
Ytterbium and Terbium Dodecaborides (open access)

Ytterbium and Terbium Dodecaborides

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
System: The UNT Digital Library