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The leachabilities of /sup 90/Sr, /sup 239/Pu, and /sup 137/Cs from solids in Tank 108-SX were determined. Through 21 leach cycles covering a 3.5 day period, 63 volumes of leachate removed 1.4, 4.6, and 19.2% of the /sup 239/Pu, /sup 90/Sr, and /sup 137/Cs, respectively, from the 108-SX solids. With the exception of the first few leachates, the /sup 239/Pu concentrations in the leachates were less than maximum permissible concentration in drinking water for 168-h/wk exposure. A composite of the TK-108-SX leachate was passed through a column containing typical Hanford soil. Column distribution coefficients with 108-SX leachate of 14, 24, and 20 were obtained for /sup 239/Pu, /sup 90/Sr, and /sup 137/Cs, respectively, indicating appreciable sorption of all these radionuclides by the soil. The radionuclides were not readily removed from the loaded soil columns with 12 column volumes of dilute leachate solution. Laboratory results with the 108-SX sludge were carefully evaluated to determine their significance to the overall analysis of the safety of long-term storage of Redox sludge in existing underground tanks. The primary deterrent to movement of the radionuclides from such solids to the water table is the absence of moving water in the storage zone. Incident precipitation does …

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This report contains a compilation of unclassified plutonium programs underway in FY 1970 in the field of materials science. It includes work in ceramics, metallurgy, solid state physics and physical chemistry. Information on each of the programs is given in five sub-headings: scope of the work; technical effort in manyears; primary class of materials studied; person(s) to contact for further information; and reports and publications. All the work listed is restricted to either research or long range development and not applied or hardware-type projects.

Di-tertiarybutylnitroxide (DTBN), which they have tried to use as a trapping agent to identify the species giving rise to the photo-induced EPR signals in photosynthetic materials, functions as a Hill reagent with spinach chloroplasts. Evidence is presented which indicates that the reduction of DTBN is affected by photosystem II of the electron transport system of spinach chloroplasts. The reduced form of DTBN, the hydroxylamine, undergoes a photo-oxidation with spinach chloroplasts. Possible explanations of this apparent inconsistency are presented. A product which could be ascribed to a chemical coupling reaction between the nitroxide and the radical species giving rise to the photo-induced EPR signals in spinach chloroplasts was not detected, even using radioactive tracer methods.

The influence upon axial stability in an electron ring of the diffraction radiation reaction force, generated by a ring moving in an acceleration column, is calculated theoretically. A stability criterion is obtained, and numerical examples show that the criterion is not an important constraint upon the choice of parameters or the operation of an electron ring accelerator.

Static quadrupole moments of the first excited states of {sup 28}Si, {sup 32}S, and {sup 40}Ar have been measured using the reorientation effect in projectile Coulomb excitation. The results obtained are Q({sup 28}Si,2{sup +}) = +0.11 {+-} 0.05 b, Q({sup 32}S,2{sup +}) = -0.20 {+-} 0.06 b, and Q({sup 40}Ar, 2{sup +}) = +0.01 {+-} 0.04 b.

Semiconductors with a sufficiently large energy gap, in contact with an electrolyte, can be used as electrodes for the study of electrochemical reactions of excited molecules. The behavior of excited chlorophyll molecules at single crystal ZnO-electrodes has been investigated. These molecules inject electrons from excited levels into the conduction band of the electrode, thus giving rise to an anodic photocurrent. The influence of various agents on this electron transfer has been studied. In the presence of suitable electron donors (e.g., hydroquinone, phenylhydrazine) in the electrolyte chlorophyll molecules, absorbing quanta, mediate the pumping of electrons from levels of the reducing agents into the conduction band of the semiconductor-electron acceptor. The electron capture by the semiconductor electrode is irreversible, when an adequate electrochemical gradient is provided in the electrode surface. An experimental technique for the study of the kinetics of photoelectrochemical reactions of chlorophyll molecules is introduced and a theoretical approach for its calculation is given. Some properties of excited chlorophyll at semiconductor electrodes (unidirectional electron transfer, highly efficient charge separation, chlorophyll as electron pump and able to convert electronic excitation into electric energy) show similarity to the behavior of chlorophyll in photosynthetic reaction centers.

Early in 1968 a research group was set up at the Lawrence Radiation Laboratory to investigate the exciting new concept of accelerating ions by means of relativistic electron rings, which had been introduced and developed by Veksler, Sarantsev, and other workers at Dubna. The initial work of our group was reported at the first USSR National Conference on Particle Accelerators in 1968. In this report the author review the subsequent progress and the present program.

Branched alkanes from blue-green algae were separated on a 750 feet high resolution capillary gas chromatographic column. The mixture was found to be 90% of 1:1 ratio 7-methyl, and 8-methyl-heptadecane, and 10% of 6-methylheptadecane. An optical rotation of +2.5 {+-} 0.5 was obtained on a 5 mg of mixture.

The authors have measured the asymmetry in the cross section for the reaction {gamma}p {yields} {pi}{sup +}n between the two stages of polarization of the initial proton normal to the plane of scattering. The initial laboratory photon energies, k, were 5 GeV and 16 GeV, and the regions of momentum transfer, t, covered were 0.14 {le} {radical}-t {le} 1.01 GeV/c and 0.14 {le} {radical}-t {le} 0.78 GeV/c respectively. A butanol polarized target was used with the SLAC 20 GeV/c magnetic spectrometer. The data show a sizeable asymmetry at both 5 GeV and 16 GeV. The 16 GeV data peak at {radical}-t {approx} 0.30 GeV/c with an asymmetry of about -0.70, and the 5 GeV data pak at {radical}-t {approx} 0.80 GeV/c with an asymmetry of about -0.70. The direction of our normal to the scattering plane is along (photon in) x (pion out).

In order to build a thin particle detector with 10 micron spatial resolution and automatic readout, the avalanche of ionization electrons in high electric fields in liquid argon and liquid xenon has been studied. We present a scheme using an array of points that could be used to make a reliable liquid argon filled detector. The avalanche pulses in liquid xenon have a rise time more than three orders of magnitude faster than that in liquid argon, suggesting that the positive charge carriers are holes, and making possible a detector with a time resolution of better than 100 nanoseconds. A direct observation of hole conduction is described.

In experiments related to the development of the electron-ring accelerator, electrons were injected into a pulsed magnetic field to form rings that were then compressed radially to a small size. The injected beam had a current of about 150 A at an energy of 3.3 MeV with an energy spread of {+-} 0.1% and a pulse length duration of 20 nsec. At low intensity, an increase in the minor radius of the ring and a large loss of electrons was observed to occur during the compression cycle. At high intensity, cooperative phenomena that caused a large increase in the energy spread accompanied by particle loss were observed. Theoretical interpretation of these observations suggests that the primary source of electron loss and enlargement of the axial dimension was the crossing of single-particle resonances during compression in the presence of large magnetic field nonlinearities and perturbations. The cooperative phenomena are interpreted as resulting from a negative mass instability. Despite the large minor radius and small number of electrons, experiments on extracting the ring were performed; under acceleration the ring failed to retain its integrity because of inadequate self-focusing.

The hydrocarbon content of leaf fossils from Iceland has been investigated by gas chromatography-mass spectrometry. The distribution patterns of normal hydrocarbons, branched hydrocarbons, and cyclic hydrocarbons are compared to those of present-day living organisms. The diagenetic pathways of these hydrocarbons are discussed.

The carcinogenic activity of the benzo[a]pyrene 1, the 7,12-dimethylbenz[a]anthracene 2 and the 3-methylcholanthrene 3 is suggested to be determine by the electrophilic attack of the active oxygen, induced by the hydroxylating enzyme systems, on the most reactive substituting carbon atom(s). The cationic intermediate(s) with the charge mainly localized on a complementary, interrelated position(s) of the hydroxyl substituted position(s) reacts further with the cellular nucleophiles. The electrophilic nature of the ultimate chemical carcinogens constitutes the common distinctive feature that correlates their different structures and allows us to understand their carcinogenicity. The formation of a covalent bond with the nucleophiles of the biological macromolecules, nucleic acids and proteins, appears to be the essential requirement in the primary process of carcinogenesis.

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The possibility of using the collective field of a large number of electrons to effect the acceleration of protons to high energies in a compact accelerator--or to permit acceleration of heavier ions in a manner not critically dependent on the charge-to-mass ratio of these ions--has been noted in an earlier Comment. A most attractive conceptual form for such an accelerator is the electron ring accelerator (ERA) and in the present Comment they direct attention to the basic phenomena--insofar as they know them--that govern the design and operation of an ERA. Briefly, the ERA concept visualizes the use of a compact ring of relativistic electrons that circulate in a plane perpendicular to an external magnetic field. The ring is partially neutralized by ions held in the potential well of the electrons. The electric field of these ions and the magnetic attractive forces between the circulating electrons then together act to overcome the electrostatic repulsion of the electrons and make possible the achievement of a configuration that is self-stable in the absence of external focusing fields. Acceleration of the ring with its accompanying ions, in a direction perpendicular to the plane of the ring, can be achieved (at the expense of the …

The procaryotic photosynthetic microorganisms Anacystis nidulans, Nostoc and Rhodospirillum rubrum have cell walls and membranes that are resistant to the solution of methane in their lipid components and intracellular fluids. But Anacystis nidulans, possesses a limited bioxidant system, a portion of which may be extracellularly secreted, which rapidly oxidizes methane to carbon dioxide. Small C{sup 14} activities derived from CH{sub 4} in excess of experimental error are detected in all the major biochemical fractions of Anacystis nidulans and Nostoc. This limited capacity to metabolize methane appears to be a vestigial potentiality that originated over two billion years ago in the early evolution of photosynthetic bacteria and blue-green algae.

Fluorescence properties of purified isoleucyl-tRNA-synthetase isolated from E. coli B have been studied. No changes in the quantum yield, energy or polarization of the emission were detected in the presence (either individually or in combinations) of the substrates and cofactors required for activation of L-isoleucine. In 2.5 M urea enzyme activity and intrinsic fluorescence intensity (at 340 nm) each decrease with time, showing similar kinetics and rate constants. The rate of this decay is reduced in the presence of ligands which can bind to the enzyme and the effect has been used to measure dissociation constants for enzyme-ligand complexes. Values have been obtained for the complexes between enzyme and L-isoleucine (K{sub diss} = 2.5 x 10{sup -5} M), L-valine (K{sub diss} = 3.0 x 10{sup -4} M), ATP (K{sub diss} = 1.5 x 10{sup -4} M) and PP{sub i} (K{sub diss} = 2.0 x 10{sup -4} M) at 25{sup o}. The effects of ionic strength, and the temperature dependence and urea concentration dependence of L-isoleucine binding have also been studied. Magnesium ions, which are required for catalysis, do not greatly affect the binding of single substrates, but changes are seen in the presence of ATP and L-isoleucine together. The magnesium …

The authors have searched for an asymmetry in the inelastic scattering of electrons from a polarized proton target in the region of resonance excitation, at values of four-momentum transfer squared of 0.4, 0.6 and 1.0 (GeV/c){sup 2}. Data were also taken using an incident positron beam in order to distinguish any possible effect of time-reversal violation from that due to higher-order ({alpha}{sup 3}) contributions to the scattering. No sizeable violation of time-reversal invariance was found.

Irradiation of benzo[a]pyrene 1 with 1-methylcytosine hydrochloride 2a (molar ratio 1:10) at 3500 {angstrom} in methanol-acetone produces the 6-(1-methylcytos-5-yl)-benzo[pa]pyrene 3. The structure of the photoproduct shows the hydrocarbon bound through the most active 6-carbon atom to the nucleophilic 5-position of the base. The specific substitution of both moieties combined with other data allows them to understand the carcinogenic activity of the hydrocarbon and thereby to propose a possible mechanism of their linkage in vivo. In this model, the K region does not play a role in triggering the cancer process.

A statistical approach is proposed to validation of SHAC models. It includes a definition of validation, an explanation of its purposes, and a description of the statistical aspects of experimental design. It proposes a study to validate design codes with statistical samples of real-world systems. Also included is a summary of present SHAC validation methodologies and studies as well as recommendations for future activity.

A study was performed of the correlation between fuel form stability and exposure environment of (temperature and atmosphere). 100% Tm/sub 2/O/sub 3/, 80% Tm/sub 2/O/sub 3//20% Yb/sub 2/O/sub 3/ and 100% Yb/sub 2/O/sub 3/ wafers were subjected to air, dynamic vacuum and static vacuum at temperatures to 2000/sup 0/C for times to 100 hours. Results showed the Tm/sub 2/O/sub 3//Yb/sub 2/O/sub 3/ cubic structure to be unaffected by elemental levels of iron, aluminum, magnesium and silicon and unaffected by the environmental conditions imposed on the wafers. A second task emphasized the optimization of the thermal, mechanical and chemical stability of Tm/sub 2/O/sub 3/ fuel forms. Enhancement was sought through process variable optimization and the addition of metal oxides to Tm/sub 2/O/sub 3/. CaO, TiO/sub 2/ and Al/sub 2/O/sub 3/ were added to form a grain boundary precipitate to control fines generation. The presence of 1% additive was inadequate to depress the melting point of Tm/sub 2/O/sub 3/ or to change the cubic crystalline structure of Tm/sub 2/O/sub 3//Yb/sub 2/O/sub 3/. Tm/sub 2/O/sub 3//Yb/sub 2/O/sub 3/ wafers containing CaO developed a grain boundary phase that improved the resistance to fines generation. The presence of Yb/sub 2/O/sub 3/ did not appear to …