The theory of isotope effects on vapor pressures for systems with large quantum effects, as manifested by the cross-over phenomenon and deviation from the rule of the mean, is illustrated by the large body of experimental data on the isotopic ethylenes which has recently become available. An effect of molecular geometry was found, viz. a difference in vapor pressures of cis-, trans- . and gemdideuteroethylenes. This was shown to be related to the hindered rotation about the C=C axis in the liquid. A further consequence of the hindered rotation was established, namely a perturbation of the out of plane molecular vibrations. This is a new effect for which a one to one correspondence with the molecular symmetry was established. Quantitative calculations show that this rotation-vibration coupling further enhances the effect of the hindered rotation. A theoretical calculation of the vapor pressure differences of the isotopic ethylenes from molecular data is made through statistical mechanical theory and the calculation of the energy states of the isotopic ethylenes. The agreement with the experimental data, which encompasses a significant number of different parameters, is quantitative.

Recent reports (1, 2, 3, 4, 5) suggest that the crystalline structure of ice permits unusual forms of energy relationships and that the structured state of water may be of importance in the whole cell. A number of biologically interesting compounds show significantly altered responses to the excitation energy of ultraviolet light in ice as compared to the liquid state. This paper describes the effect of a change in phase state on a biologically active nucleoprotein, a bacteriophage particle. Phage is found to be much more sensitive to inactivation by ultraviolet light when irradiated in frozen aqueous suspension than when irradiated at room temperature (7): the sensitive target appears to be the phage DNA.

Periodically irradiated and annealed graphites show property changes that are markedly different from the changes after the first irradiation and anneal. Evidence is presented indicating the existence of consecutive reactions between interstitial complexes that lead to steady state concentrations of the intermediate species in a chain. The steady state concentrations result in dimensional recoveries and stored energy releases that do not increase with irradiation as they do in continuously irradiated graphites. Interstitial complexes, formed by a thermal anneal, interact through an integral chain via mobile single interstitials. Kinetic equations of chains reacting at one or both ends are described. The calculations for chains reacting at both ends show that large complexes can decompose to form smaller ones. Experimental evidence supporting the calculations shows that periodic removal of the smaller complexes of large amounts of damage associated with the layer interstitials.

The driving force for liquid metal corrosion is the equilization of chemical potential for dissolution of all solid surfaces in contact with the liquid. In any practical system, this is an impossible goal; therefore, one observes several mass transfer processes.

Harrison and Paskin (HP) have calculated the ordering energy of β-CuZn using recent theoretical techniques of treating electron screening and Mott's polar model of an alloy. Good agreement is obtained between the calculated total energy of the order-disorder transformation and specific heat measurements. A consequence of the HP calculation is that the ordering energy is long-range and oscillates in sign. Walker and Keating recently measured the neutron diffuse scattering of β-CuZn above the critical temperature Tc and find their data is in agreement with order calculated by only considering a nearest neighbor interaction. Using the Cowley statistical theory of order, we compare the order generated by a nearest-neighbor interaction and the long-range interaction of HP at a temperature 1.1Tc. we find the average behavior of the order generated by the nearest-neighbor and long range interaction to be similar, The major difference is the nearest-neighbor interaction generates order that asymptotically, varies smoothly with neighbor distance whereas the order resulting from the long-range interaction fluctuates markedly about the nearest-neighbor generated order. This result may explain the success of statistical theories, based on nearest-neighbor interactions, in both order-disorder of alloys as well as in some magnetic systems which are also believed to have …

The solution time of analogue multipliers using field-effect transistors is investigated. This time is ultimately limited by the charging time of the field-effect transistor junction. In typical devices suitable for analogue multiplication the charging time is found to be about 10-20 nsec less than one percent. A four quadrant pulse amplitude multiplier circuit is described, whose solution time is equal to the field-effect transistor charging time.

The basic similarity in cytochrome physiology between Anacystis nidulans ad Euglena gracilis, strains Z, is impressive in view of their gross dissimilarities in size, structure, and pigment content. We have investigated the cytochrome reactions by sensitive spectrophotometric methods in order to gain some insight into the patterns of energy transfer from the various light receptors to the reaction centers involved in the two photochemical reactions of green plant photosynthesis and also to elucidate the pathways of photosynthetic electron transfer. The major thrust of this presentation will be the implications of experiments on whole cells in which both wavelength and intensity of monochromatic actinic light have been systematically varied. Some preliminary observations of the effect of carbonyl cyanide-m chlorophenylhydrazone (CCCP) are presented, and the light-driven reduction of cytochrome b6 in Euglena chloroplast fragments is described.

A model has been developed for the analysis of current reversal chronopotentiograms in systems where the electrode process is followed by a homogeneous second order reaction. The model is analyzed using the IBM 7094 digital computer programed in FORTRAN language. Working curved, derived with the aid of dimensional analysis, can be used to evaluate rate constants from experimental data. The electroreducation of uranium (VI) to uranium (V) with subsequent second order disproportionation of uranium (V) has been studied as an experimental test of the model. Disproportionation rate constants thus obtained are in satisfactory agreement with previously reported values. Other possible applications of the model are discussed.

The radiolysis of several polyaromatic compounds which might be used as coolant material in a reactor was investigated using both gamma and reactor radiation. The compounds selected were naphthalene, anthracene, naphthacene, pyrene, phenanthrene, 1, 2 benzanthracene, chrysene, triphenylene, 9, 10 dihydrophenanthrene, phenazine, 7, 8, benzoquinoline and m-phenanthroline, in addition to the uncondensed ring compounds, biphenyl, ortho, meta and para terphenyl and bibenzyl. Gas yields, percentage decomposition, percentage "high boiler" and number average molecular weights were determined. A correlation was found between radiation stability and electron affinity and singlet triplet excitation energies. The most stable compounds were the condensed ring compounds, naphthalene, pyrene, chrysene, phenanthrene and triphenylene.

A pool of material in steady-state turnover is a collection of identical molecules from which deletions are made at a constant rate, along with simultaneous addition of new identical molecules at the same rate, the total pool size remaining unchanged. It is of interest to consider what may be expected in the way of such pools among the various chemical species which can be isolated from biological systems. It is clear what the model requires, i.e. any molecule belonging to the pool must have as much chance as any other pool molecule to make its exit. This situation is approximated by molecules in solution in a well mixed volume of fluid, hence the choice of the word "pool." The mixing brings pool molecules into proximity with the exit mechanism in a random way.

In a continuation of the study of the properties of the φ meson we have roughly doubled the available data on the φ production via the reactions [equations were not transcribed]. The data discussed here was obtained in the Brookhaven National 20" Hydrogen Bubble Chamber exposed at a separated beam of K- of 2.24 Gev/c.

The importance of the examination of paper and textile supported art objects by means of low energy X-rays has been ably discussed in the preceding papers of this session. The apparatus used for such radiography, however, has tended to be both expensive and confined to laboratory use. A lack of mobility arises from the weight and size of X-ray apparatus and the fact that its installation frequently requires shielding and special electric power lines. An inexpensive radiographic apparatus that required no special installation or external power and is small and light enough to be easily portable should be quite useful.

The increasing complexity of the data of nuclear physics has led to widespread interest in the possibility of utilizing a digital computer for on-line data collection. Through the combined efforts of the Instrumentation Division and the Neutron Physics group at Brookhaven such a system has been placed into operation. Several features of this system are believed to be unique and of interest to research groups centered about a major facility like a reactor or an accelerator.

The heavy metal intoxications involving the brain may be divided into two groups: One, in which the offending metal is clearly a poison, such as mercury or lead; and a second, in which the offending agent is normally an essential constituent of the body. The latter category would include manganese poisoning, copper poisoning (or Wilson's disease) and, if some recent data are valid, Huntington's chorea, in which iron seems to have been implicated. Our interest in the second category of diseases is due to the fact that these conditions represent special aberrations of normal homeostasis. Homeostasis is the sum of the processes which maintain constant structure, function and constitution in the body and its organs. In manganese poisoning, the homeostatic control is disturbed by virtue of oversupply of this element via an abnormal route (the respiratory tract), while in Wilson's disease homeostasis is disturbed by virtue of genetically transmitted abnormal avidity of the body for dietary copper. In the present paper, we will discuss first some of the clinical features of chronic manganese poisoning in order to raise some questions about extrapyramidal syndrome in general. Thereafter, we will allude to some investigations conducted at this center during the last ten …

The descriptive parameters of a waveguide with smooth or periodic structure are most easily measured in a waveguide section of suitable length which is transformed into a resonant cavity by placing short circuits at both ends. Measurements of dispersion diagram, phase velocity, group velocity, voltage attenuation coefficient, shunt impedance, field configuration, etc. all involve some form of perturbation technique. The introduction of a perturbing object in a resonant cavity changes the stored electric energy We and magnetic energy Wm by Δwe and ΔWm' resulting in a frequency shift Δf of the resonant frequency f, which is given by the perturbation formula of J. Muller.

The Brookhaven Bubble Chamber Group is developing a Hough-Powell fast analysis system (HPD)1 for bubble chamber photographs. High precision measurements are made with a computer controlled flying spot digitizer. We are currently testing the track selection programs for the system. We have just completed a study of a method for automatic bubble density measurements.

We undertook the present diffraction study of the bifluoride ion in sodium acid fluoride and the present refinement of the earlier data on potassium acid fluoride with the hope of obtaining more accurate information not only on the position of the hydrogen atom, but also on the vibrations of the ion. We felt that it would be through the combination of information on the motions of the system from diffraction and spectroscopic studies that the question of the symmetry of the ion could be settled. In this paper we summarize briefly the results of our diffraction study and show that these data, in combination with the spectroscopic data, provide new, and we feel convincing, evidence that the F-H-F ion is linear and symmetric.

Early effects obtained with monoenergetic fast neutrons in mice have been described elsewhere. Emphasis in this report will be placed on the late effects of lens opacification (cataractogenesis), particularly during the period soon after irradiation with low or fractionated doses of neutrons at two energy levels, or X-rays. Considerations will also be given to the influence of age at time of irradiation upon the induction of lens opacities. Both studies are continuing, with periodic slit-lamp microscope examinations, but findings to date warrant this initial report at this conference.

Brookhaven has sponsored a summer program to study possible experimentation with super-high-energy accelerators of ~ 1000 BeV and to examine the feasibility of colliding beam experiments. A group of about fifty physicists took part in this study program. These investigations are a continuation and supplementary to our previous studies at Brookhaven about two years ago.

Investigations on the relative biological effectiveness (RBE) of densely ionizing radiations (with high LET, rate of linear energy transfer) are of importance in both fundamental and applied radiobiology. In the latter, they serve as a basis in setting permissible exposure levels for types of radiation about which little long range experience is available. Some of the best RBE studies have been done on chromosomal aberrations. The difficulty is determining RBE on the basis of chromosomal exchanges or 2-break aberrations is that the dose-response curves differ for radiations of different LET and dose rate. The dose-squared term tends to predominate with radiations of low LET (such as γ rays and most X rays) and high doses or dose rates; the linear term dominates with high LET tracks in general and at low doses or dose rates. The shape of the curves is thought to reflect the existence of two classes of mechanisms by which chromosome exchanges are produced; exchanges caused by the passage of a single ionizing particle account for the linear component of the dose-response curve, exchanges due to the interaction of effects of two independent ionizing particles are responsible for the dose-squared component. This model has been amply confirmed …

If one injects into an animal H3-thymidine, 50% of it is incorporated into deoxyribonucleic acid (DNA), within approximately 30 to 45 minutes, while the rest is catabolized. A storage of H3-thymidine for later incorporation into DNA does not occur, on the basis of available evidence. Once incorporated, the label remains bound to DNA until cell death and no unequivocal evidence has as yet been presented to indicate metabolic renewal or intracellular turnover of the DNA molecule. The loss of labeled DNA from the bone marrow is therefore directly influenced by the rate of proliferation of the various cell types with release of mature cells into the peripheral blood.

A strong motivation for metabolic investigations of essential metals lies with the simple fact that these elements are primordial metabolites and building blocks of living matter, a truism largely forgotten today. Among them, the metals of the first transition group display high physical and chemical flexibility: They can concomitantly coordinate natural or artificial ligands; they can regulate electron and proton transport; they can act as catalysts or as cofactors to catalysis.

In brief, these facilities consist of a 250 KvP X-ray generator; two areas of a research reactor, one a well thermalized unit of moderate capacity and a larger area with a mixed thermal and fast neutron distribution, all of which are used for brief, acute exposure. A 10 acre field, currently with almost 4000 curies of cobalt 60, serves to irradiate entire plants for either short or long periods of time. Recently, the flux density of the thermal column was increased by a factor of 5 over the original density. This was accomplished by lowering the thermal column 12 inches deeper into the reactor shield. Fast neutrons at this higher flux density are also available to the cooperator. An additional facility available to the program is the array of kilocurie gamma sources in the Nuclear Engineering Department of Brookhaven National Laboratory.

It has been previously reported that within twenty days following bombardment of mice 10 MeV protons (as well as with 20 MeV deuterons and 40 MeV alpha particles) that atypical epithelial hyperplasia developed without underlying recognizable vascular or collagen alterations as predisposing factors. The source of these monoenergetic accelerator-produced heavy ionizing particles was the 60-inch cyclotron of the Brookhaven National Laboratory. The technique employed utilized a variable-thickness filter in the beam in order to deliver multiple Bragg peaks in depth in the path of the charged particles in the tissue being irradiated. In this way a cylinder of skin was bombarded with essentially uniform ionization limited to a depth of 1-2 mm. In some instances the epidermal lesions resulting from an exposure of 2000 to 5000 rad resembled the type of lesion considered in the skin of man to be carcinoma in situ. The eventual fate of such lesions then constituted a question of importance in the possible relationship atypical hyperplasia in the pathogenesis of carcinoma in situ and of invasive carcinoma in skin. It is with this problem that the currently reported study is concerned.