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The Effects of Radiations of Different let on Early Responses in the Mammal

Description: This paper will first note briefly the place and status of radiobiotopical investigations with fast neutrons. The monoenergetic (fast) neutron technique employed at this laboratory will be then described and results of studies with various criteria-of-effect in the mouse will be reviewed. Finally, certain general patterns of response for these systems will be pointed out as functions of neutron energy.
Date: February 1, 1963
Creator: Bateman, J. L. & Bond, V. P.
Partner: UNT Libraries Government Documents Department
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Use of a Digital Computer in the Development of a Positron Scanning Procedure

Description: The problem to be discussed originates in our interest in the diagnosis and treatment of brain tumors. It has been established by others that some positron-emitting radioactive isotopes, in particular Arsenic-74 and Copper-64, can be causal to localize in brain tumors and thus to serve as agents for locating the tumors. Although other kinds of radioisotopes have also been used successfully in locating tumors, positron emitters have some especially attractive features. Their use is based on the principle that a positron, or positively charged electron, is a form of "anti-matter," and when it encounters an ordinary negatively charged electron both are annihilated, giving rise to two gamma rays that are emitted in opposite directions. Such an event is detectable through the use of coincidence counting. The data for which the method of analysis is to be discussed in the present paper is generated by a device using the coincidence counting method with multiple detectors in an arrangement potentially suitable for three-dimensional localization of brain tumors.
Date: February 1, 1963
Creator: Robertson, James S. & Niell, Arcadio M.
Partner: UNT Libraries Government Documents Department
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The Effects of Chronic Gamma Irradiation on the Growth of Kalanchoe cv. "Brilliant Star"

Description: Kalanchoe seedlings were exposed to 330 r/20 hrs/day from a Co60 source. Samples were harvested weekly. No new leaves were produced after initial exposure to irradiation. Mitosis in the apical meristem appears to have been suppressed. However, the axillary meristem and the cambium continue their activity. This results in a much broadened stem tip with enlarged cells, supported by a stout internode in which cell size has remained relatively normal but cell number has increased. After about 26 days of exposure, meristematic activity in the shoot apex region appears to resume. This results in the formation of growth centers which can give rise to leaves or malformed structures. The original phyllotaxy is not recovered. It is suggested that this resumption of growth may be an instance of adaptation to irradiation.
Date: February 1, 1963
Creator: Stein, O. L. & Sparrow, A. H.
Partner: UNT Libraries Government Documents Department
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Inelastic Interactions of 11.4 Bec/c π" Mesons in Hydrogen

Description: Production cross sections and angular distributions of Λ and K° particles produced by 11.4 Bev/c π" mesons in hydrogen have been measured. A systematic investigation was made of all two-body decays of unstable neutral particles. No events inconsistent with γ, Λ, or K° were found. Production cross sections, angular distributions and effective mass distributions of π mesons produced in 4-prong events were also measured. No evidence for dominance of any high mass multi-pion resonance was found. Both the pion production and strange particle production reactions demonstrated peripheral characteristics in that the baryon was strongly peaked backward in the center of mass. The average transverse momentum was observed to be a monotonically increasing function of mass. The experimental total interaction cross section was 25.3 ± 1.5 mb. The effect of the pion-nucleon T ' 3/2 isobar was clearly observed.
Date: February 1, 1963
Creator: Ferbel, T. & Taft, H.
Partner: UNT Libraries Government Documents Department
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Chronic Excess Salt Consumption as an Etiologic Factor in Human Hypertension

Description: Since 1940 it has been known that extra salt (i.e. sodium chloride) facilitated the development of experimental hypertension induced by various sterols; subsequently hypertension was induced by desoxycorticosterone acetate plus sodium chloride; then hypertension was produced by using hypertonic saline as the sole source of liquid; and finally, in 1953, Menesly and his associates reported that chronic ingestion of excess dietary salt alone would produce hypertension in rats. Furthermore, in conformity with general pharmacologic experience relating dose response to successive increments of a drug, as the average daily salt intake increased, the average systolic, blood pressure increased.
Date: February 1, 1963
Creator: Dahl, Lewis K.
Partner: UNT Libraries Government Documents Department
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Possibilities and Limitations in the use of Tritiated Thymidine for in Vivo Cytokinetic Studies on Lymphoreticular Tissue

Description: Tritiated thymidine (H3TDR), a specific precursor of deoxyribonucleic acid (DNA), has proved to be a valuable tool in the study of in vivo cellular kinetics. Various methods of analysis have been used in autoradiographic investigations of proliferative patterns and time parameters in different cell lines.
Date: February 1, 1963
Creator: Cottier, H.; Odartchenko, N.; Feinendegen, L. E. & Bond, V. P.
Partner: UNT Libraries Government Documents Department
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The Function of Bridging Groups in Electron-Transfer Reactions

Description: Electron-transfer reactions involving bridged transition states are examined from the point of view of adiabatic electron transfer theory. One important function of the bridging group is to decrease the effective dipole moment of the charge system of the reaction ions. The effect on the activation energy is different for outer-sphere and inner-sphere reactions. Trends in the halide and hydroxide catalysis of isotopic exchange reactions of transition metal ions are discussed.
Date: February 1, 1963
Creator: Hush, N. S.
Partner: UNT Libraries Government Documents Department
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Di-Interstitial Annealing During the First Neutron Irradiation of Graphite: The Mobility of C2

Description: Radiation and annealing mechanisms for dimensional and c-axis changes in which the di-interstitial can be mobile at any or all temperatures above absolute zero are shown to be concordant with earlier work used to determine the migration energy energy of single interstitials and the absolute rate of displacing atoms in graphite. The mechanisms account for the stability of c-axis and dimensional changes with time in the absence of irradiation and with observed c-axis annealing at room temperature following irradiation at low temperatures.
Date: February 1, 1963
Creator: Schweitzer, Donals G.
Partner: UNT Libraries Government Documents Department
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Transport of FissionProducts Through the Soil Following Injection From a Well and Methods Used for Removal

Description: In the summer of 1960 one of the little used wells on the Brookhaven National Laboratory site became accidentally contaminated with radioactive material. The contamination was discovered during a routine sampling of all wells in the waste disposal area, so there was a period of several weeks between the time of discharge.
Date: February 1, 1963
Creator: Gemmell, L. & Pearsall, S. G.
Partner: UNT Libraries Government Documents Department
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The Calculation of Zero-Point Energies of Molecules by Perturbation Methods

Description: Two methods are proposed for calculating zero-point energies of molecules. The first makes use of the fact that one can easily write down the quantum mechanical Hamiltonian for a vibration system. The zero-point energy can then be obtained by a perturbation scheme without solving the secular equation. The second method requires a knowledge of the normal modes and frequencies of a reference molecule, but then enables one to calculate isotope effects by a perturbation scheme. The methods are applied to some examples and the convergence of the perturbation series is investigated. The approximate validity of the law of the mean for the isotope effect on zero-point energies is explored within the framework of the methods.
Date: February 1963
Creator: Wolfsberg, Max
Partner: UNT Libraries Government Documents Department
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The Use of Tritiated Thymidine in the Study of Tissue Activation During Germination in Zea Mays L.

Description: The transition from dormancy to growth in plant seeds has been the topic of many biological studies (1,2). Of particular interest to the radiobiologist are the dramatic changes in radiosensitivity occurring soon after the soaking of the seeds (3). These changes are thought to be associated with the commencement of proliferative activity. The recently developed method of labeling DNA with tritiated thymidine allows analysis of proliferative activity in greater detail than was heretofore possible. In the present study, uptake of tritiated thymidine and mitotic counts were used to determine the sequence of activation of proliferation in tissues or organs of the germinating corn embryo.
Date: February 1, 1963
Creator: Stein, O. L.
Partner: UNT Libraries Government Documents Department
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Fundamental Problem of Late Neurological EffectFollowing Acute Irradiation

Description: Since the end of the last century (Tarknow, 1896) radiation effect o the nervous tissue has been studied in experimental animals and humans by numerous investigators, using mostly pathomorphological changes as a parameter of radiosensitivity . With increasing time intervals following radiation, pathomorphological changes are more evident, which has been known for quite some time.
Date: February 1, 1963
Creator: Yamamoto, Y. L.
Partner: UNT Libraries Government Documents Department
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Short Time Strength Data for CS 1830 Series Cb-1Zr, Annealed at 2200F

Description: This technical report is a summary of short time strength data for CS1830 series Cb-1Zr material. The data are presented as a function of fabrication history or the amount of cold work received during fabrication. Three fabrication categories were considered for comparison: forgings and extrusions; bar, plate, rod and pipe; and sheet and tubing. Forgings and extrusions having received no cold work showed the highest strength over the entire temperature range 68F to 2800F; bar, plate, rod and pipe received moderate cold work and showed lower strength than forgings and extrusions but higher strength than sheet and tubing in the temperature range 2000F to 2800F.
Date: February 8, 1963
Creator: Watson, W. L.
Partner: UNT Libraries Government Documents Department
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Niobium-Tin-Aluminum Alloy Studies

Description: From Abstract : "A proposed constitutional diagram was developed from equilibrium data obtained for the niobium-tin binary alloy system. ... Alloying Nb3Sn with Nb3Al appears to raise the zero field superconducting transformation temperature of Nb3Sn slightly."
Date: February 1963
Creator: Ellis, Thomas Gordon & Wilhelm, Harley A.
Partner: UNT Libraries Government Documents Department
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Gamma Ray Efficiencies for Well Type Scintillation Crystals

Description: From Abstract : "Gamma ray efficiencies for various sized well type NaI(Ti) crystals have been calculated using an IBM 704 digital computer. The adjustable parameters in the program are the gamma ray energy, the heights and diameters of the crystal and the well, the thickness of the well lining, and the positions of the (point) source inside the well. Some typical results are presented in graphical form."
Date: February 8, 1963
Creator: Dingus, Ronald S. & Stewart, M. G.
Partner: UNT Libraries Government Documents Department
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Acid-Base Reactions in Fused Salts. Dichromate-Bromate Reaction

Description: Technical report. From Abstract : "The reaction of Lewis acid and base, Cr2O7= and BrO3_, in fused KNO3 - NaNO3 mixtures has been shown to involve an equilibrium followed by a slow decomposition to gaseous products."
Date: February 1963
Creator: Duke, F. R. & Schlegel, James
Partner: UNT Libraries Government Documents Department
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The Strontium-Strontium Hydride Phase System

Description: Technical report. From Abstract : "The Sr-SrH2 phase diagram was studied by thermal analysis, chemical analysis of equilibrated phases and X-ray diffraction. The maximum solubility of SrH2 in strontium metal is 38 mole % at the peritectic temperature of 880°C. Strontium metal undergoes an allotropic transformation at 555°C and melts at 768°C. A second transformation was found, at about 240°C, in samples containing hydrogen. Strontium hydride was found to have an allotropic transformation at 855°C."
Date: February 20, 1963
Creator: Peterson, D. T. & Colburn, R. P.
Partner: UNT Libraries Government Documents Department
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High Pressure Research at Low Temperatures

Description: Two principle reasons exist for the extension of high pressure research to temperatures near absolute zero. First, the comparison of certain data with theory (such as the pressure-volume relationship) is more meaningful if the effects of thermal vibrations can be ignored. Second, there are phenomena which can be studied only at low temperatures. These include superconductivity, the properties of solid helium and other inert gases, some electronic phenomena, etc.
Date: February 24, 1963
Creator: Swenson, C. A.
Partner: UNT Libraries Government Documents Department
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NPR tritium production

Description: No Description Available.
Date: February 14, 1963
Creator: Baranowski, F. P.
Partner: UNT Libraries Government Documents Department
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