A study of aluminum recovery from power plant fly ash by high temperature chlorination was undertaken to demonstrate that fly ash could be a potential source of aluminum, iron and possibly silicon. Magnetic separation of the iron oxide served as a first step to alleviate the iron contamination problem. However, the agglomeration of some iron oxide with alumina and silica made it difficult to completely separate the iron from the fly ash. Further iron separation was achieved by chlorinating the nonmagnetic ash fraction at 550/sup 0/C for 30 minutes. This reduced the iron oxide content to less than 4 percent by weight. Chlorine flow rates affected the reaction rate much more drastically than temperatures. This suggested that diffusion was the major rate-controlling step. Besides Fe/sub 2/O/sub 3/, Al/sub 2/O/sub 3/ and SiO/sub 2/, other oxides such as CaO, K/sub 2/O, Na/sub 2/O and MgO might have complicated the alumina recovery by forming individual chlorides or complexes. Investigating methods for separating more Fe/sub 2/O/sub 3/, and possibly CaO, K/sub 2/O, Na/sub 2/O and MgO from the nonmagnetic ash fraction before chlorinating it is highly recommended.

Evaporated films of La, Ce, Yb, Y, Ag--Mn(5 percent), KCl, MnF$sub 2$, CsCl and LaF$sub 3$ were studied using the soft x-ray appearance potential spectroscopy (SXAPS) technique. Studies were also made of bulk polycrystalline samples of Y, Zr, Nb, and Mo. The results are discussed in terms of existing SXAPS theories. Several similarities between soft x-ray absorption (SXA) data and the SXAPS results are discussed, and it is shown that the SXA data can aid in the interpretation of SXAPS spectra when using the well-known self-convolution model. In this approximation the absorption coefficient, $alpha$(E), is substituted for the density of states, N(E-E/sub c/) $Yields$ $alpha$(E). For more localized excitations, a convolution of $alpha$(E) with bremsstrahlung isochromat data, based on Wendin's two density of states formalism is used to predict SNAPS results. (auth)

This report addresses the design and performance of the atom probe field ion microscope.

None

The proton NMR in powdered samples of H/sub 2/O(s), H/sub 2/S(s), and C/sub 6/H/sub 6/(s) have been studied by multiple pulse line narrowing techniques. The resultant spectra provide nuclear magnetic shielding tensors that are (at least approximately) axially symmetric. The anisotropy is 34.2 +- 1.0 ppM for ice, 11.1 +- 1.0 ppM for the highest-temperature phase of solid hydrogen sulfide, and -5.3 +- 0.3 for benzene. Comparisons are made with previous experimental and theoretical work.

None

The crystal and molecular structures of the following organophosphorus (OP) insecticides have been determined by three-dimensional X-ray analysis: ronnel (0,0-dimethyl 0-2,4,5 trichlorophenyl phosphorothioate), ronnel oxon (0,0-dimethyl 0-2,4,5 trichlorophenyl phosphate), bomophos (0-(4-bromo-2,5-dichlorophenyl) 0,0-dimethyl phosphorothioate), Ruelene (0-(4-tert-Butyl-2-chlorophenyl)-0-methyl-N-methyl phosphoroamidate), fospirate (0,0-dimethyl 0-3,5,6-trichloro-2-pyridyl phosphate) and chlorpyrifos (0,0-diethyl 0-3,5,6-trichloro-2-pyridyl phosphorothioate). Phosphorus to meta hydrogen distances for the respective compounds are: 5.51, 5.49, 5.42, (5.68, 5.13), 5.79 and 5.78 A. All of these distances fall well within the range of literature values cited for the intramolecular active site-separation distance for insect acetylcholinesterase (AChE), yet are well outside that for mammalian AChE. In addition the crystal structure of ronnel displays a hydrogen-sulfur intermolecular interaction in the b direction and a phosphorus which is readily accessible for phosphorylation of AChE. The structure of ronnel oxon is quite similar to that of ronnel. CNDO 11 molecular orbital calculations are presented to show the charge distribution in the compound. A likely intramolecular hydrogen bond in bromophos restricts rotation about the phenolic C-O bond. The configuration of Ruelene is substantiated by CNDO 11 molecular orbital calculations and van der Waals arguments and features a possible weak intramolecular hydrogen bond which somewhat restricts rotation about the phenolic C-O bond. Charge density information …

The $sup 2$D quadrupole interaction was observable in all the samples of LaNi$sub 5$D/sub x/ up to a critical temperature T/sub c/ at which the intensity of the quadrupole interaction spectrum disappeared and only a narrow unsplit line remained. The critical temperatures were 360$sup 0$K for the x = 3.6 sample and 380$sup 0$K for the x = 5.7, 6.7 samples. Based on preliminary electric field gradient (EFG) calculations, it appears likely that several quadrupole interactions are being observed from inequivalent deuterium sites in the lattice. In the temperature range T greater than or equal to 300$sup 0$K, it appears that diffusional averaging is not entirely isotropic and that the deuterium still occupies certain interstitial sites preferentially. The temperature dependence of the $sup 2$D characteristic quadrupole frequency ($nu$/sub Q/) and the disappearance of the $sup 2$D quadrupole interaction signal were found to be compatible with desorption of the deuterium from the LaNi$sub 5$ lattice with increasing temperature. Spectra obtained from D$sub 2$ gas samples under various experimental conditions (pure gas, gas above LaNi$sub 5$D$sub 6$.$sub 7$, and gas within or on LaNi$sub 5$ at 77$sup 0$K) may provide evidence for the identification of the solid-solution $alpha$-phase or for the existence …

None

P-type germanium single crystals (8 x 10/sup 14/Ga/cm/sup 3/ and 6 x l0/ sup 1 Ga/cm/sup 3) were irradiated with 1.1-Mev electrons at pumped liquid helium temperatures and defect production and annealing studied using ac hopping conductivity. Production rates obtained from measurements at 1.5 deg K and 10/ sup 4/ Hz were 0.6 cm/sup -10/ for samples doped 6 x 10/sup 15/ Ga/cm/sup 3/ and 0.11 cm/sup -10/ for samples doped 8 x 10/ sup 14/ Ga/cm/sup 3/. Above 10/sup 14/ e,/cm/sup 2/ fluence the production rates for the higher doped samples decreased to approximately 0.06 cm/sup -1/ at 10/sup 15/ e/cm/sup 2/ fluence except for one sample which was anomalous. No such long irradiation of the low doped samples was made. The apparent inconsistency between these results and production rates of less than 3 x 10/sup -4/ cm/sup -1/ observed by previous workers was resolved by introducing a donor level for the defect produced by irradiation near the chemical acceptor level, so that the defect would be neutral at temperatures near 30 deg K and charged + 1 at l.5 deg K. Surface effects were observed which did not affect production rate measurements at 1.5 deg K more than …

Europium oxide is presently being tested for use as the control material in future nuclear power reactors. Elastic properties of europia and selected europia-rich compositions of the europia-hafnia system were investigated. The sonic technique was employed to measure elastic moduli from room temperature to 1500$sup 0$C. Sintered monoclinic europia specimens were found to have uncommonly low room temperature moduli values and to exhibit hysteresis between heating and cooling curves because of the presence of microcracks caused by thermal expansion anisotropy. Fine grained hot pressed europia as well as sintered specimens that contained at least 6 mole percent hafnia did not exhibit these characteristics. Photomicrographs revealed that grain growth suppression was produced by and related to the amount of hafnia introduced. Hysteresis loops in the moduli versus temperature measurements were exhibited only by those specimens for which the average grain size was in excess of a critical value of 8 $mu$m. Dilatometer measurements indicated that thermal expansion was relatively constant over the compositional range of interest. (auth)

The electric mobility and effective valence of hydrogen and deuterium in vanadium, niobium, tantalum and three niobium-tantalum alloys were measured. A resistance technique was used to directly determine the electric mobility of hydrogen and deuterium at 30/sup 0/C while a steady-state method was used to measure the effective valence. The use of mass spectrographic techniques on a single specimen which contained both hydrogen and deuterium greatly increased the precision with which the isotope effect in the effective valence could be measured.

The feasibility of calculating Wagner self-interaction parameters from binary phase diagrams was examined. The self-interaction parameters of 22 non-ferrous liquid solutions were calculated utilizing an equation based on the equality of the chemical potentials of a component in two equilibrium phases. Utilization of the equation requires the evaluation of the first and second derivatives of various liquidus and solidus data at infinite dilution of the solute component. Several numerical methods for evaluating the derivatives of tabular data were examined. A method involving power series curve fitting and subsequent differentiation of the power series was found to be the most suitable for the interaction parameter calculations. Comparison of the calculated self-interaction parameters with values obtained from thermodynamic measurements indicates that the Wagner self-interaction parameter can be successfully calculated from binary phase diagrams.

The application of fault tree analysis (FTA) to system safety and reliability is presented within the framework of system safety analysis. The concepts and techniques involved in manual and automated fault tree construction are described and their differences noted. The theory of mathematical reliability pertinent to FTA is presented with emphasis on engineering applications. An outline of the quantitative reliability techniques of the Reactor Safety Study is given. Concepts of probabilistic importance are presented within the fault tree framework and applied to the areas of system design, diagnosis and simulation. The computer code IMPORTANCE ranks basic events and cut sets according to a sensitivity analysis. A useful feature of the IMPORTANCE code is that it can accept relative failure data as input. The output of the IMPORTANCE code can assist an analyst in finding weaknesses in system design and operation, suggest the most optimal course of system upgrade, and determine the optimal location of sensors within a system. A general simulation model of system failure in terms of fault tree logic is described. The model is intended for efficient diagnosis of the causes of system failure in the event of a system breakdown. It can also be used to assist …

A variant of the maraging class of steels is proposed for application at 77$sup 0$K and below where a combination of very high strength and good toughness is required. The alloy has a composition of Fe-12Ni-4Co-2Mo-0.05Ti where low interstitial content. The as quenched and quenched and aged structures were completely martensitic with a prior austenitic grain size of 10 to 12 $mu$m. This structure had a Y.S. of 138.5 ksi and 154 ksi before and after aging respectively. All aging was done at 444$sup 0$C for 4 hours. The DBTT was shown to lie above 77$sup 0$K as measured by C/sub v/ testing. Based on dilatometric studies of the $alpha$ $Yields$ $gamma$ and $gamma$ $Yields$ $alpha$ transformation temperatures a cycling treatment consisting of reportedly heating to above the A/sub f/ temperature followed by a water quench was utilized to further reduce the prior $gamma$ grain size to approximately 4 to 6 $mu$m. The structure was completely martensitic and possessed a Y.S. of 151 ksi at 77$sup 0$K in the unaged condition with a Y.S./K/sub IC/ ratio of 1.9 while the aged structure showed a Y.S. of 162 ksi with a Y.S./K/sub IC/ ratio of 1.3. C/sub v/ testing showed the …

None

Off-line experiments indicated that fluorides of As, Se, Br, Kr, Zr, Nb, Mo, Tc, Ru, Sb, Te, I and Xe could be volatilized, but except for Br, Kr, I and Xe, none of these elements were observed after mass separation in the on-line experiments. The results of the on-line experiments indicated a very low level of hydride contamination at ambient temperature and consequently, uranium tetrafluoride replaced uranyl stearate as the primary gaseous fission product target. Possible reasons for the failure of the heated target system to yield non-rare gas activities are discussed and suggestions for designing a new heated target system are presented.

Iodoacetamide has been shown by others to be a radiation sensitizer for bacteria and for certain mammalian cells tested in vitro. This work describes an examination of the effectiveness of iodoacetamide used in vivo. Survival of ascites tumor cells maintained in the peritoneal cavity of mice was used as an indicator of sensitization. Survival was assessed using TD{sub 50} and total tumor cell population determination methods. A comparison of results obtained by these methods is made. The effects of oxygen tension and radiation dose rate upon results was examined. Iodoacetamide was found to be effective as a radiation sensitizer under all conditions although to a lesser degree than that reported by others for in vitro experiments with bacteria. Radioactive tracer studies indicate that iodoacetamide has rapid and total access to most if not all tissues of the body. This fact coupled with the observation of a sensitization in an in vivo system where the anoxia so prevalent in well developed tumors was present, suggests the possibility of clinical usefulness of iodoacetamide in cancer radiation therapy. Certain observations are reported on the effect of various cell and host treatment procedures upon cell population growth kinetics seen subsequent to inoculation of hosts …

None

None

Thesis. Starting with partial wave amplitudes for pi N yields N pi and pi N yields several isobar model states of N pi pi , one can apply the constraint of unitarity (using the K-matrix). This permits the removal of the overall phase ambiguity of the isobar amplitudes at each energy. The K-matrix fits generated a smooth prescription for the T-matrix amplitudes, enabling one to search the complex energy plane for poles. The uniqueness of these poles was demonstrated by doing Breit-Wigner refits to the fitted T-matrix amplitudes. The success of the results and the obvious interpretation justified a simple determination of coupling signs for which there can be checks with theory. This thesis corresponds closely to a forthcoming paper submitted to Physical Review except that here the K-matrix is based on a 1972 solution A'' isobar-model fits to N pi pi data, and in the final paper solution B'' is used. (auth)

The heat capacity of high purity electrotransport refined lutetium was measured between 1 and 20/sup 0/K. Results for theta/sub D/ were in excellent agreement with theta values determined from elastic constant measurements. The heat capacity of a series of lutetium-hydrogen solid solution alloys was determined and results showed an increase in ..gamma.. from 8.2 to about 11.3 mJ/g-atom-K/sup 2/ for hydrogen content increasing from zero to about one atomic percent. Above one percent hydrogen ..gamma.. decreased with increasing hydrogen contents. The C/T data showed an increase with temperature decreasing below about 2.5/sup 0/K for samples with 0.1 to 1.5 atomic percent hydrogen. This accounts for a large amount of scatter in theta/sub D/ versus hydrogen content in this range. The heat capacity of a bulk sample of lutetium dihydride was measured between 1 and 20/sup 0/K and showed a large increase in theta/sub D/ and a large decrease in ..gamma.. compared to pure lutetium.

None

None