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."

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."

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.

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."

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."

From Abstract : "The solubilities of the individual rare earth lactates and α-hysroxyisobutyrates in water at 20 and 60° were determined for comparison with the rare earth glycolate solubilities determined earlier."

The heavy gas model using a synthetic kernel leads to coupled equations for the determination of the neutron flux in a bare reactor. The very special problem of solving analytically the defining equation for the energy dependent neutron flux in a region for which there are no source terms is considered. (auth)

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.

"Research in thermal contact resistance at MIT and advances made during the past year are summarized. The problem of predicting cortact resistance is examined in an analysis of a model for the contact which relates the geometry of actual surfaces in contact to the contact model, and a deformation analysis which relates the contact geometry to the load carried by the surfaces. Experimental procedures are described and are applied to two stainless steel surfaces in contact and to W and graphite surfaces in contact. A significant result is that a surface may be described by two measurable parameters which may be combined with two such parameters of any other surface to completely determine the geometry of the interface if they are placed in contact. It thus remains to construct a device which will readily measure these two parameters."

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

It has been established by chromosome marker studies, histochemical, immunological, and cytological methods that the hemopoietic tissues of animals exposed to lethal doses of whole-body irradiation can be repopulated by transfused autologous, homologous or heterologous bone marrow cells. However, the morphology of the cell responsible for the regeneration of hematopoietic activity in the various hemopoietic organs has not been identified. It has been shown that the bone marrow contains the cell or cells capable of regenerating all types of hemopoietic tissues. In order to identify transfused cells, one must have a label which persists through successive divisions. Odell and Smith labeled the donors with S35 methionin and were thus able to follow the accumulation of the donor marrow cells in the recipients lungs and subsequently their releases to the bone marrow and spleen. However, this compound has a relatively rapid turnover in the labeled cells and thus a relatively limited capability of serial studies to observe mitosis and differentiation. Tritiated thymidine is ideal for this purpose since it is incorporated solely into DNA and is diluted only by mitosis. In addition the high resolution with tritium makes it certain that one is observing nuclear labeling. Bond et al. have studied …

Previous attempts by the present authors to compare the behavior of orally administered vitamin B12 with that of injected material have been inconclusive. Thus, 30 days after administration to normal humans, 0.19% of a tracer amount (0.5 μg) of injected radioactive vitamin B12 is excreted per day; and in an independent study, the eventual daily output was found to be 0.23% of a 3 μg dose. By contrast the total excretion rate of normal vitamin B12 from body stores appears to be only ≈0.03% per day. Such a divergence may result from incomplete mixing of radioactive vitamin B12 and body stores of the vitamin. Alternatively it may actually reflect the functioning of different compartments attending the several modes of administration involved. The possibility of degradation or transformation of vitamin within tissues and organs must also be considered.

The aim of this series of experiments was to evaluate the existence of abscopal effects of irradiation. No attempt was made towards the elucidation of mechanisms. Very early in the history of radiological research it was noticed radiation produces both local and general effects involving the entire body. Gauss and Lembcke introduced the term "Roentgenkater" (radiation sickness). They ascribed these "General Effects" to the circulation of toxic substances released from cells that disintegrated following irradiation.