A research program is being conducted to obtain experimental data in the irradiation of plutonium-enriched fuel to confirm a theoretical model for predicting isotopic composition and reactivity changes in plutonium-enriched, light-water-moderated reactors. Quarterly progress: Project fuel fins irradiated to 1860, 3000, and 5300 MWD/T have been successfully sampled in the Radioactive Materials Laboratory. The samples have been dissolved and aliquots delivered to Chemistry for Mass Spectrometry and burnup determination. The first Stanford Pool Irradiation indicated that there was some inconsistency in the thermal flux and the near thermal epithermal flux. The experiment was repeated, increasing the number of foil wheel positions from two to three. The data from the second measurement are being reduced. The EPITHERMOS code modification has been completed. Comparisons between the results computed by the code and experimental data show much improved agreement. The metallographic photomicrographs of a polished half-pellet from rod F, irradiated to 5000 MWD/T, show structure very similar to that shown by the pellet from rod S, irradiated to 1860 MWD/T.

Work performed during the quarter is summarized by: direct measurement of fission gas pressure, loop operations, performance of UO2 fuel, UO2 grain growth and melting studies.

A research program is being conducted to obtain experimental data in the irradiation of plutonium-enriched fuel to confirm a theoretical model for predicting isotopic composition and reactivity changes in plutonium-enriched, light-water-moderated reactors. Quarterly progress: Work has begun in the Radioactive Materials Laboratory to sample the project fuel from the pins irradiated to 1800 and 5000 MWT/T. Some delay has been experienced due to preemption of the hot cells by priority work. Examination of the autoradiographs of the un-irradiated project fuel showed that in a volume of fuel approximately equivalent to a pellet there were 13 hot spots larger than 15 mils. Evaluation of these spots with the fuel analyzer showed that they contained about 14 mg of PuO2 or about 9% of the total present. The EPITHERMOS code is being modified to automatically normalize the epithermal scattering to the correct value for all moderators. Calibration of the flux wires has been made and the reduction of the data from the VBWR irradiation is nearly complete. A similar resonance activation was made in the water reflector of the Stanford Pool Reactor to obtain the relative activity in a well-defined pure water spectrum. Reduction of these data is also in progress.

From introduction: "This is the eighteenth in a series of quarterly reports which cover the progress and results from the conceptual designs, economic evaluations and research and development work performed by the General Electric Company as part of Contract AT(01-3)-189, Project Agreement No. 13."

Quarterly progress report discussing activities related to the Vallecitos Boiling Water Reactor (VBWR) and related facilities.

Work performed during the quarter is summarized by: direct measurement of fission gas pressure, loop operations, performance of UO2 fuel, UO2 grain growth and melting studies.

A research program is being conducted to obtain experimental data in the irradiation of plutonium-enriched fuel to confirm a theoretical model for predicting isotopic composition and reactivity changes in plutonium-enriched, light-water-moderated reactors. Quarterly progress: Forty-six fuel pellet faces have been auto-radiographed. These faces have been prepared from twenty-three pellets by making an exposure before and after the removal of an additional ten mils of fuel. A substantial number of large "hot spots" continue to appear. The largest spot so far observed was 44 mils long, 20 mils wide, and of the order of 20 mils thick. This spot has a PuO2 concentration which varied from 70% on the periphery to 100% at then center. There is some evidence that the segregated regions are elongated with their long axes perpendicular to the direction of the pressing of the green pellet. Determination of the size and concentration distribution is continuing. The EPITHERMOS code now seems to be operating correctly. A test problem for a typical water lattice converged in eleven iterations. The computation of the spectrum for a pure water medium gave results which agreed very well with the expected 1/E spectrum. At the end of the quarter, the program fuel element …

Introduction: The literature reflects ever expansive studies of radiation chemistry over the past twenty years However, in the application of radiation processing to chemical reactions, in general and excepting a few isolated cases, the yield of useful products have been so low as to preclude practical utilization. Thus, for many reactions,radiation alone at ambient conditions is not a sufficient agent for economical production. Hence, we are led to the investigation of radiation effects on reactions at elevated temperatures and pressures where the thermodynamics favor more extensive reactions that may be induced by radiation. the probability of developing a successful practical radiation process is increased when applying radiation at rigorous conditions. To have a commercial advantage, a radiation process usually must replace an expensive catalyst system, generate a reaction at somewhat less rigorous conditions than is usually employed or yield a better or unique product of high value. In our investigations, we have examined only the potential of radiation as a replacement for contact catalyst. Results: We have worked with coal extract rather than coal because it can be melted or dissolved to facilitate pumping into the processing unit and, in general, permits easier handling than a solid. From numerous radiation …

From introduction: "This is the seventeenth in a series of quarterly reports which cover the progress and results from the conceptual designs, economic evaluations and research and development work performed by the General Electric Company as part of Contract AT(01-3)-189, Project Agreement No. 13."

Technical report describing that as part of the AEC Fuel Cycle Program, tests are being conducted to evaluate the significance of current fuel design limitations that do not permit the maximum fuel temperature to exceed the melting point of UO2. The reliability of prediction of the fuel rod operating conditions that will cause melting of the UO2 was evaluated by means of a calibration test conducted in the Vallecitos Boiling Water Reactor. Conclusions: (a) The central portion of the 3.15-cm diameter uranium dioxide fuel column melted. It appears that the UO2 was molten to a radius of 1.22 cm in the peak power region. The maximum extent of melting probably occurred during the peak power run when the kdT in this region of the rod reached 171 watts cm. The estimated radius of melting from metallographic examination indicates the kdT for sintered UO2 is 89 watts/cm. This supports a calculated estimate for sintered UO2 thermal conductivity published by D. R. deHalas and G. R. Horn. The results of the previous calibration run and subsequent experimental data by Lyons are also consistent with the value. This conclusion is contingent on the interpretation of the post-irradiation crystal structure of the UO2. Insufficient …

Since the discovery of the Straub and Feuer as well as Laki et al. that ATP bound to G-actin is transformed to ADP and inorganic phosphate during polymerization of actin (1, 2), it has become increasingly clear that the chemical changes in the nucleotide are related to the change in the physical state of the protein. Barany, Biro, Molnar and Straub have shown that highly purified actin preparation free of any enzyme which would use ATP, ADP or AMP as a substrate still catalyze the breakdown of ATP (3) thus supporting the original idea that the ATP to ADP transformation is related to the globular to fibrous transformation of the actin protein itself. Mommaerts was the first to show that the ADP formed during polymerization remains bound to F-actin and Ulbrecht et al. while extending Mommaert's finding on exhaustively purified actin preparations have shown that the P1 formed during polymerization is not bound to F-actin. The stoichiometry of the splitting and the tightness of binding of the ADP lead inevitably to questions in regard to the position of bond breaking during the hydrolysis and to the nature of the forces involved in the tight binding of ADP to F-actin. To …

The scope of the AGS complex has expanded rapidly during the three years since an accelerated beam was first obtained. Demand for research time far exceeds the amount available although facilities have been much increased. At the same time, experiments are being designed which are more complicated than previous ones and which make more stringent demands on the accelerator and on its auxiliary equipment. There is a continuous trend of experiments to particle beams of greater momentum, as the experimental techniques are refined. This use of increased momentum means that larger areas are required for the apparatus and that more power is necessary for the magnetic optics. All beam-sharing at the AGS is done by multiple use of each accelerated pulse because our experience indicates that pulse-by-pulse beam-sharing is relatively inefficient. (Expansion chambers have seldom been used at the AGS.) The problems of scheduling experiments becomes increasingly complex since combinations must be found satisfying the criteria: maximum number of experiments to run simultaneously; minimum downtime to be taken for rearrangement between successive experimental arrays

In the vast field of radiation pathology we find pathologists, anatomists, and even physiologists busily at work, but the radiobiologist is conspicuously absent, although, according to Zirkle (1959), this field is clearly within his domain. Perhaps it is wise to take this broad hint of the scientifically so well equipped radiobiologist and to stay clear from an area in which an incalculable array of variables makes clearcut experimentation a hopeless venture, a priori. Perhaps it would be better if the pathologist, who must study pertinent material, restricts himself humbly to the recording of his observations, refraining from any attempt at interpretation. On the other hand, since seemingly audacious speculation has borne fruit in the past and the value of the information that results, if the speculation proves to be correct, is worth many times the effort, there is obvious justification for a thesis on the mechanism of delayed radionecrosis.

Activities in a program to develop techniques in the use of pulsed neutron sources to measure shutdown parameters related to large thermal power reactors are reported. The development of pulsed neutron source techniques for large power reactors has led to a new theoretical model recently developed by E. Garelis and J.L. Russell, Jr. The theory is presently based on a bare, one-group model with m-delayed precursors and takes all spatial modes into account. Results indicate, however, that the application of this model is much broader. Experiments were designed and carried out to both verify this new theory and to demonstrate the performance of the experimental hardware in a large power reactor.

Summary: A prototype control rod containing absorber plates made from an electro- deposited dispersion of boron carbide in nickel was tested in the VBWR. It was exposed to the reactor environment of 545 degree F boiling water and thermal neutron fluxes (perturbed) which ranged from 0.6 to 1.1 x 10/sup 13/ nv for 2236 hours over a period of six months. The maximum B/sup 10/ burnup achieved during the test period was 1.8 percent. After irradiation, the rod was examined. The results of the examination are summarized below: (1) The B/sub 4/C-- Ni plate assembly did not undergo significant dimensional changes during irradiation. (2) Numerous blisters developed on both the outer and inner surfaces of three of the four plates. Blistering was more severe on the outer surface than on the inner, and was most severe in a large region located in the lower half of plate 4. Metallographic examination revealed that the blisters were located only in the 2- mil protective nickel overlay covering the B/sub 4/C-- Ni dispersion. It was concluded that they formed from the buildup of gas pressure at the Ni: Ni-- B/sub 4/C interfaces, rather than from corrosion attack. Helium from the B/sup 10/(n alpha …

The duration of mitosis is of great importance in an evaluation of growth rates in proliferating somatic tissues, since calculations are based on observations of mitotic activity, and therefore final results are directly proportional to an assumed value for mitotic time. This duration cannot be measured directly in vivo at a tissue level, since the mode of distribution of the single cell value is not known. This difficulty is not overcome in extrapolations from in vitro measurements. Also it is not overcome with the labeling of proliferating cells after tritiated thymidine injection in vivo if subsequent observation is limited to the rate of progression into mitosis of labeled cells that incorporated the tracer during the period of DNA-synthesis. Observation of separate mitotic phases, however, offers the possibility of following the progression of the wave of labeled cells at successive, short-lasting checking steps, and to analyze the variability in the times of passage through mitosis. In the present work, the progression of labeled cells as a function of time, after a single injection of tritiated thymidine, was followed in successive phases of mitosis in erythroblasts of dog bone marrow.

The development of nuclear arms added the effects of ionizing radiation to the direct and indirect mechanical, chemical or thermal hazards of "conventional" weapons. The biological effects of ionizing radiation are the result of absorption of energy and the morphologically recognizable damage is poorly understood. Although new in their use in weapons and difficult to evaluate in their consequences, ionizing radiations are by no means new to physicians. Furthermore, medical experience has shown that clinical consequences of radiation injury are similar to those with which the clinician has to deal with every day in the treatment of neoplastic disorders and its complications. Soon after the discovery of x-rays by Roentgen and of the phenomenon of radioactivity by Bequerrel in the last decade of the last decade of the 19th century, it was found that ionizing radiation can produce marked biological effects by interfering with cell- and organ functions. Senn and Hussey were the first to effectively treat leukemia by this means. This, since about 60 years, ionizing radiation has been a powerful tool in the hands of physicians both in diagnostic procedures and for therapy of malignant disease. It should not be forgotten however, that the price paid for this …

Work performed during the quarter is summarized by; direct measurement of fission gas pressure, loop operations, performance of UO2 fuel, UO2 grain growth and melting studies.

Studies on a large variety of plant species, particularly by Sparrow and his colleagues, have shown that radiosensitivity, as measured by growth inhibition and lethality, is strongly correlated with various parameters of the cell nucleus. Foremost among these are nuclear volume, SNA content and chromosome number. It is generally accepted that in proliferating cell systems chromosome damage may well be the principal radiobiological lesion, and the observed correlations are in line with the contention that loss of genetic materials following such fragmentation is a factor of a major importance in radiation-induced lethality and growth inhibition in plants.

In the fall of 1961 an extensive program of investigation of high energy p-p interactions was begun at the Brookhaven AGS. The BNL 20" liquid hydrogen bubble chamber and an electrostatically separated beam were used to obtain a total (to date) of 300,000 exposure with about 15 antiprotons per pulse. The exposures were made at antiproton momenta of 3.25 Bev/c and 3.69 Bev/c in the laboratory. Approximately 80% of the exposures were made 3.69 Bev/c antiprotons. A wide variety of reactions occur in these collisions. Some of these such as elastic scattering, pion production, and associated production of hyperons and K-mesons have analogues in p-p collisions. The similarities and differences between the p-p and p-p results can usually be understood in a qualitative way and in some cases quantitative comparison with theory has been possible. The annihilation reactions leading to final states containing pions alone or pions with K-mesons are unique to the nucleon-antinucleon system as are the reactions in which a hyperon, anti-hyperon pair is produced. In the following, we report the principal characteristics of proton-antiproton reactions. Although the scope of this paper is comprehensive it is not a definitive report of the experiment as much of the work …

The kinetics of several oxidation-reduction reactions involving manganese (III) have been studied spectrophotometrically by the use of a flow technique. The free energies of activation for the oxidation of various substituted tris-(1,10-phenanthroline) complexes of iron (II) by manganese (III) in perchloric acid and in pyrophosphoric-sulfuric acid media were found to be linearly related to the standard free energy changes of the reactions. The application of the Marcus theory to the reactions of manganese (III) with iron (II) and with various substituted iron (II)-phenanthroline complexes and to the reaction of cobalt (III) with manganese (II) in perchloric acid leads to an estimate of about 10 -4 F -1 sec -1 for the rate constant of the manganese (II)-manganese (III) electron exchange reaction at 25.0°. Attempts to determine the rate constant for this exchange by a radioactive tracer method were unsuccessful.

Binary fluorides of the type XMnF3 (X= Na, Rb, Cs, and NH4), which were investigated previously by means of x-ray, electron spin resonance specific heat, and magnetization measurements, have been reported to be antiferromagnetic. The present study reports powder neutron diffraction measurements on these compounds undertaken to confirm the antiferromagnetism and to study details of the magnetic ordering. Some information was also obtained concerning the nuclear structures.

The present communication reports the results of several investigations of magnetic structure and magnetic transitions currently in progress or recently completed at Brookhaven National Laboratory.

A feedback technique has been developed to equalize the DC levels of two signal sources so that AC signal components which are much smaller than the DC levels can be compared accurately without introducing a low frequency cut-off and consequent rate-dependency into the system. A digital integrator in the feedback loop provides a highly stable long-term "memory" so that the correct level will be maintained during intervals when the signals are "frozen" at some arbitrary point.