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The development and testing of a demonstration brushless alternator for the ML-1 mobile nuclear power plant is described. The brushless concept was selected after it became apparent that a conventional power generator could not satisfy the ML-1 weight and size requirements. The demonstration alternator fabricated and tested under this program did not meet all performance specifications; the efficiency was low and the unit could not be operated for significant periods of time without overheating. However, a large body of useful data was accumulated during the extensive development program. Of special interest are data on the rotor and stator design, the cooling requirements and on the distribution of eddy current losses. Analysis of the data indicates that a brushless alternator, only slightly larger and heavier than was specified for the ML-1, could be developed with a modest additional effort.

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Evidence is presented which points to (at least) two bound forms of bacteriochlorophyll present in chromatophores of Rhodospirillum rubrum, both of them readily converted to unbound bacteriochlorophyll (abs. max. 770 mu) when the chromatophores are extracted with acetone or ethanol. Controlled oxidation of the chromatophores with Ir(IV) or with Zn(II) and ferricyanide preferentially destroys the more strongly absorbing pigment (abs. max. 880 mu) but brings about only a slight decrease in the magnitude of the photoinduced absorption changes at 810 and 792 mu. Such oxidations yield a new pigment, absorbing at 715 mu in the aqueous preparation and, more strongly, at 680-684 mu when the pigment is extracted into organic solvents. This pigment is formed irreversibly and is therefore different from the material formed by photooxidation of chromatophores. Its visible spectrum and the spectrum of the material formed from it by acidification suggest that it is a chlorophyll-like substance, possibly derived from bacteriochlorophyll by (two-electron) oxidation of one of the dihydropyrrole rings to a pyrrole ring. Directions are given for separation of this pigment from other colored compounds present in the oxidation mixtures.

The recently completed 25-inch hydrogen bubble chamber combines excellent picture quality with a fast operating cycle. The chamber has a unique optical system and is designed to take several pictures each Bevatron pulse, in conjunction with the Bevatron rapid beam ejection system. At present the chamber operates twice per Bevatron pulse. The general features of the chamber constructiosn are shown in Figs. 1 and 2. The chamber is ten inches deep at the narrowest point. The magnet is of conventional water cooled design and in present operation produces a vertical field of 18.5 kgauss. With suitable generators it has produced a field of 22.8 kgauss. The most important new features are discussed below.

Phosphorus pentoxide reacts with ether to form bicyclo-tetraphosphate ester (II), cyclotetraphosphate ester (III), isocyclotetraphosphate ester (IV), and tetraphosphate ester (V). Phosphorus n.m.r. measurements show the content of the mixtures. The so-called 'ethyl metaphosphate' (Langheld ester) is a mixture of III (50% to 45%), IV (36% to 25%), and V (14% to 30%).

Using the Berkeley polarized-proton target, we have measured the polarization parameter P({theta}) for proton-proton (p-p) scattering. The measurements were obtained at beam kinetic energies of 0.330, 0.680, and 0.740 GeV at the 184-in. synchrocyclotron and 1.70, 2.85, 3.50, 4.00, 5.05, and 6.15 GeV at the Bevatron. The angular regions measured were from 20 to 100 degrees center of mass; the square of the four-momentum transfer ranged from 0.1 to 0.8 (GeV/c){sup 2}.

The effect of finite resistance in the vacuum-tank walls on the longitudinal stability of an intense beam of particles in an accelerator is investigated theoretically. We show that even if the particle frequency is an increasing function of particle energy, the wall resistance can render the beam unstable against longitudinal bunching. In the absence of frequency spread in the unperturbed beam, the instability occurs with a growth rate that is proportional to (N/{sigma}){sup 1/2}, where N is the number of particles in the beam and {sigma} is the conductivity of the surface material. By means of the Vlasov equation a criterion for beam stability is obtained. In the limit of highly conducting walls the criterion involves the frequency spread in the unperturbed beam, the number of particles N, the beam energy, geometrical properties of the accelerator, but not the conductivity {sigma}. A numerical example presented indicates that certain observations of beam behavior in the MURA 40-Mev-electron accelerator may be related to the phenomenon we investigated.

The prebiotic synthesis of phosphorus-containing compounds--such as nucleotides and polynucleotides--would require both a geologically plausible source of the element and pathways for its incorporation into chemical systems on the primitive Earth. The mineral apatite, which is the only significant source of phosphate on Earth, has long been thought to be problematical in this respect due to its low solubility and reactivity. However, in the last decade or so, at least two pathways have been demonstrated which would circumvent these perceived problems. In addition, recent results would seem to suggest an additional, extraterrestrial source of reactive phosphorus. It appears that the 'phosphorus problem' is no longer the stumbling block which it was once thought to be.

Reversible photoinduced electron paramagnetic resonance (EPR) signals and photoconductivity were observed when a solution of tetracyancethylene (TCNE) in tetrahydrofuran (THF) was irradiated in the charge-transfer band of the complex formed between these two compounds. The eleven-line hyperfine structure of the EPR spectrum which was obtained demonstrated the presence of TCNE negative ion radical. The concentration of this radical was found to be directly proportional to the square root of the light intensity. Second order decay kinetics were followed when the light was shut off. Both the EPR signal and the photoconductivity rose initially as the square of the time. The latter portions of the growth curves could be fit to the latter portions of a hyperbolic tangential growth curve. From these data a reaction mechanism was proposed. The rate law dn/dt + kn{sup 2} = {alpha}L(1-e{sup -{beta}t}) = 0, where n = the concentration of radicals, t = the time, k, {alpha}, and {beta} are rate constants, and L = the light intensity, described both the photo-induced EPR and the photoconductivity within the limits of experimental accuracy.

About 70,000 pictures of 2.45-GeV/c K{sup -}-p interactions have been obtained in the present 72-inch hydrogen bubble-chamber experiment. Approximately 24,000 events of all topologies except 1-, 2-, and 3-prong events have been measured, and 50% have been remeasured. They report here on a study of the production of known resonances in the reactions: (1) K{sup -} + p {yields} {Lambda} + {pi}{sup +} + {pi}{sup -}; (2) K{sup -} + p {yields} {Lambda} + {pi}{sup +} + {pi}{sup 0} + {pi}{sup -}. The cross section for production and number of events in reactions (1) and (2) are given in Table I.

We have successfully conducted a series of experiments involving scattering of high energy pions and protons from a target containing polarized protons. Results of some of these experiments were reported at this conference, and in the literature. Proton polarizations as high as 65% have been measured; the average polarization during sustained data-taking has been typically 45%.

The decay kinetics of the photo-induced absorbance changes in red and green algae are very sensitive to the wavelength of the actinic 11ght. A four to twofold increase in half-decay time is noted in going from short wavelength (550-650 mu) to long wavelength (> 700 mu) excitation. The slow decay ratios, produced by long wavelength light can be enhanced with a steady background of short wavelength light. A relationship between initial decay rates and 02 evolution rates is described. This relationship allows a direct correspondence between these spectroscopic studies and the 'red-drop' and 'enhancement' experiments of Emerson.

Program 3 of Operation BREN consisted in a study of the performance of biological shields composed of various arrangements of steel, water, and borated polyethylene in spherical, cubical, and parallelepipedal geometries. Studies were also made of the radiation levels within concrete-lined and -capped pits, 4 ft in dia and 8 ft deep. The principal radiation source was the ORNL Health Physics Research Reactor, an unshielded, unreflected, 90 wt % U-10 wt % Mo, cylindrical bare-metal assembly. It was supported at heights ranging from 27 to 1500 ft by a hoist car riding outside of a 1527-ft-high steel tower. A 1200-curie Co/sup 60/ gamma-ray source, similarly supported, was substituted for the reactor for some measurements. The work reported includes measurements of fast-neutron and gamma-ray dose rates and thermal-neutron fluxes in air and within the various shields, using the reactor source, measurements of gamma-ray dose rates in air from the Co/sup 60/ gamma-ray source, and measurements of gamma-ray pulse-height spectra within the pits, also employing the Co/sup 60/ source. 8 refs., 33 figs., 29 tabs.

A number of burnout tests have been run subsequent to the publication of the burnout equations in DP-355 and DP-725. The range of variables was extended in these tests and the burnout heat flux was measured. This memorandum presents a modified empirical equation, which correlates the new data, for use in the design of fuel assemblies for the HWCTR. We expect to submit this material for a journal publication within the next quarter.

Operation of the present accelerator is summarized and plans for a new injection system and additional machine modernization are described. Research results of both experimentalists and theorists are reviewed in very brief summaries; references are provided. (RWR)

Information is presented concerning coated fuel particle development and evaluation; burnup capabilities of Y/sub 2/O/sub 3/-stabilized UO/sub 2/ and stabilized fuel - BeO matrix materials; high-temperature studies of substoichiometric urania and urania solid solutions; high-temperature carbides and borides research; and high-flux reactor materials gaseous fuels research.

The altitudes and times of ablation have been determined for the SNAP-10A, SS-316 vessel wall reentering under various conditions. The results are confined to one typical location on the reactor and to one typical reentry trajectory. The location is the side wall of the vessel and the trajectory is the one used in NAA-SR-8303.

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Work was continued on the development of a process for the gasification of bituminous coal with heat from a nuclear reactor. Major objectives of the project are: (1) develop and test components for a gas-cooled reactor system that can heat gases to 2000/sup 0/ to 2500/sup 0/F; (2) investigate coal gasification methods compatible with this system; and (3) develop an exchanger that can utilize high-temperature heat to gasify coal or heat chemical process streams. During the past year, work was concentrated on the design, construction and installation of a fluidized-bed gasifier in the high-temperature heat system. Design of the fluidized-bed gasifier was based on information obtained from laboratory and pilot-scale gasifiers. The gasification chamber, a length of 6-inch, schedule 80 stainless steel pipe, is fitted with ten 1/2-inch Hastelloy-X tubes running lengthwise. Hot helium flowing through the 1/2-inch tubes provides heat for the gasification of the steam-fluidized char in the 6-inch pipe. Helium leaving the gasifier generates the superheated steam required for gasification. Fabrication and installation of the gasifier was completed and shakedown runs started. In the gasifier, the heat-exchanger tubes will be heated to 1900/sup 0/F in a mixture of the corrosive gases, including H/sub 2/, CO, CO/sub 2/, …

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