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Auger and Reaction Studies of Poisoning by Sulfur and Regeneration of Metal Synthesis Gas Catalysts. Progress Report: April 1, 1975--December 15, 1975

Description: The objective is to determine the rate and mechanism of (1) sulfur poisoning and (2) of regeneration of metal catalysts used in synthesis gas conversion to hydrocarbon products. Auger electron spectroscopy (AES) is used for surface analysis, and in-situ reaction studies of deactivation and regeneration are combined with microreactor studies to quantify sulfur poisoning. An all-glass internal recirculation microreactor has been designed, fabricated, debugged and integrated into a metal-free feed… more
Date: December 1975
Creator: Katzer, James R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Changes in surface conditions with first plasma in the Princeton Large Torus (PLT)

Description: In--situ measurements are reported of the changes in surface composition of 305 stainless steel exposed to the first plasma discharges in PLT. Auger electron spectroscopy of pre-exposure surfaces shows a multilayer coverage of carbon and a fractional monolayer coverage of oxygen. Surfaces subjected to increasing levels of plasma exposure show substantial removal of the carbon multilayer, increased fractional-monolayer coverages of oxygen and iron, and tenth-monolayer quantities of chlorine and … more
Date: January 1, 1976
Creator: Dylla, H.F. & Cohen, S.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Photoelectron spectroscopy and Auger electron spectroscopy of solids and surfaces

Description: The use of photoelectron spectroscopy, primarily x-ray photoelectron spectroscopy, to obtain information on the electronic structure of a wide variety of solids (especially the bulk electronic structure of solids) is covered. Both valence band and core-level spectra, as well as a few cases of photon excited Auger electron spectroscopy, are employed in the investigations to derive information on N(E). The effect of several modulations inherent in the measured I(E)'s, such as final state band str… more
Date: January 1, 1976
Creator: Kowalczyk, S. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study of grain boundary segregation using the Auger electron emission technique. Annual technical progress report VI, January 1, 1976--December 31, 1976. [Summary of research activities at Michigan Tech]

Description: Studies of admirality brass stress corrosion in copper sulfate and copper nitrate have provided information on environmental contributions to SCC in acid systems. SCC susceptibility is a function of bulk corrosion rate, and is maximized when conditions favor localized attack. At a given pH and stress, solution composition determines crack initiation rates, but the crack crevice environment is not characteristic of the bulk salt solution. Crack propagation appears to be strongly related to anodi… more
Date: January 1, 1976
Creator: Stein, D. F.; Heldt, L. A.; Lee, J. K. & Pinchback, T. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Surface characterization of ceramic materials. [LEED, AES, XPS, ion scattering spectroscopy, secondary ion mass spectroscopy]

Description: In recent years several techniques have become available to characterize the structure and chemical composition of surfaces of ceramic materials. These techniques utilize electron scattering and scattering of ions from surfaces. Low-energy electron diffraction is used to determine the surface structure, Auger electron spectroscopy and other techniques of electron spectroscopy (ultraviolet and photoelectron spectroscopies) are employed to determine the composition of the surface. In addition the… more
Date: September 24, 1976
Creator: Somorjai, G. A. & Salmeron, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Determination of the surface composition of binary alloys by Auger electron spectroscopy: the gold--silver and gold--tin systems

Description: Auger electron spectroscopy was exploited as a means of determining the surface phase diagram of Au--Ag and Au--Sn alloys. Polycrystalline Au--Ag alloy foils of a wide range of composition (atom fractions of 0.15 to 0.97) were cleaned. The intensities of the Auger emission from transitions at several energies were measured and normalized to those of pure Au and Ag. The surface monolayer compositions of the alloys were determined. The Auger data was consistent with enrichment of Ag in the surfac… more
Date: November 1, 1976
Creator: Overbury, S. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Auger and Reaction Studies of Poisoning by Sulfur and Regeneration of Metal Synthesis Gas Catalysts. Progress Report, December 8, 1975--December 8, 1976

Description: CO methanantion rates have been measured in the all-glass internal recycle reactor developed for this work. The methanation rate over the cylinder Ni film catalyst at 400/sup 0/C is 3.9 sec/sup -1/ initially, and the catalyst undergoes deactivation to a value of 1.8 sec/sup -1/, comparable with a reported value of 2.5 sec/sup -1/. The activation energy for Ni film on alumina is 24 kcal/mole, that for Ni film on silica is 17.8 kcal/mole comparable to values for Ni on these supports. The kinetics… more
Date: December 10, 1976
Creator: Katzer, James R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Rate and pressure dependence of contaminants in vacuum deposited aluminum films

Description: Experiments were conducted to measure the quantity of trapped impurities in electron beam-deposited aluminum films. The depositions were conducted at the 1.3 x 10/sup -4/ Pa to 1.3 x 10/sup -2/ Pa pressure range with rates varying from a few A/sec to 70 A/sec. An RGA was used to record the residual gas spectrum before and during all runs. The films were analyzed by sputter profiling and Auger Electron Spectroscopy. The chief contaminants found were carbon and oxygen. The carbon contaminant trac… more
Date: January 1, 1977
Creator: Springer, R.W. & Catlett, D.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Study of grain boundary segregation using the Auger electron emission technique. Annual technical progress report, VII, January 1, 1977--December 31, 1977

Description: An analysis of plastic flow at the tip of a propagating crack during brittle fracture has been developed. The plastic flow analysis takes into account the anisotropy of slip by a mixed mode opening scheme. Values of the true fracture energy for different crack systems are obtained; the effects of an embrittling agent can be taken into account. The fracture stresses of Cu--Bi alloys having varied grain sizes and Bi concentrations were measured. Dilute alloys exhibited a decreasing fracture stres… more
Date: January 1, 1977
Creator: Stein, D. F.; Heldt, L. A.; Clough, S. P.; Hack, J. A.; Pinchback, T. R. & Vonk, S. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Interaction of nitric oxide wth the (1010) face of ruthenium

Description: The low-energy electron diffraction (LEED) technique was used to probe the atomic geometry of the surfaces that resulted from the steady-state interaction of nitric oxide with Ru(10 anti 10) as a function of temperature and pressure. Auger electron spectroscopy (AES) was used to identify the atomic species present on these surfaces. Results were obtained at reactant partial pressures in the range from 10/sup -9/ to 10/sup -6/ torr and substrate temperatures from -25 to 950/sup 0/C. The interact… more
Date: February 1, 1977
Creator: Orent, T. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Luminescence studies of oxygen absorption on thorium

Description: The interaction of oxygen with a thorium metal surface is being studied by monitoring the luminescence of thorium in an electron beam. By combining luminescence measurements with Auger electron spectroscopy data, it is possible to distinguish between processes that depend upon the oxygen pressure at the sample surface, and those that depend only upon the amount of adsorbed oxygen.
Date: February 15, 1977
Creator: Bastasz, R.; Colmenares, C. A.; Smith, R. L. & Somorjai, G. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Auger-electron line-shape study of CVD silicon nitride films

Description: The shapes of integral Auger-electron signals from chemical-vapor-deposited silicon nitride with 0.3 at percent and 12 at percent oxygen have been compared with each other and with signals from clean Si and SiO/sub 2/. The data show the probable existence of elementally bound Si in the nitrides. Incorporation of oxygen decreases the structure associated with elemental Si but does not cause the Si L/sub 2/,/sub 3/ VV line shape to change to that characteristic of SiO/sub 2/. The nitrogen peak sh… more
Date: May 1, 1977
Creator: Madden, H. H.; Moore, G. & Holloway, P. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Ion backscattering studies of Synthoil catalyst materials. [2 MeV /sup 4/He/sup +/ ions]

Description: Energetic ion backscattering has been used to analyze new and used CoMo catalyst pellets in support of the SYNTHOIL Process catalyst deactivation study. These analyses enabled the first absolute quantitative determinations of atomic composition and compositional gradients within the pellets. In cases where they can be compared, the backscattering data agree with data from parallel analysis programs using the electron microprobe and Auger spectroscopy. Enrichment of Mo and Ca in the outer 2 ..mu… more
Date: May 1, 1977
Creator: Borders, J. A. & Peterson, G. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Catalysis studies

Description: The New Research Initiatives Program (NRIP) project on catalysis in Los Alamos Scientific Laboratory (LASL) Group CMB-8 has made significant progress towards performing the first basic in situ experimental studies of heterogeneous catalysis on solid compound surfaces in a LEED-Auger system. To further understand the surface crystallography of a possible catalyst compound, LEED-Auger measurements were made on UO/sub 2/(approximately 100) vicinal surfaces. These (approximately 100) vicinal surfac… more
Date: November 1, 1977
Creator: Taylor, T. N. & Ellis, W. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Auger study of surface carbon and oxygen on thorium following ion bombardment

Description: The composition of a thorium metal surface has been monitored using Auger electron spectroscopy following Ar/sup +/ bombardment at different temperatures. After extended Ar/sup +/ bombardment, enough contaminated overlayers were removed to expose a surface region containing only thorium, bulk impurities, and imbedded argon. The main impurities, carbon and oxygen, differed in their behavior when the sample was annealed following bombardment. The amount of surface carbon either increased or remai… more
Date: November 17, 1977
Creator: Bastasz, R. & Colmenares, C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Scanning Auger electron spectroscopy studies of grain-boundary segregation in Type 304 stainless steel

Description: Scanning Auger electron spectroscopy studies have been conducted on grain-boundary surfaces of Type 304 stainless steel that were fractured in situ. To enhance the probability of intergranular fracture, the specimens were first subjected to creep deformation for 1000 h at 700/sup 0/C. A semiquantitative surface chemical composition was calculated from the peak heights of Auger electron spectra. The concentration of Cr at the fracture surface was not different from the bulk value. This indicates… more
Date: January 1, 1978
Creator: Park, J.Y.; Danyluk, S. & Busch, D.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Study of grain boundary segregation using the Auger electron emission technique. Annual technical progress report, VIII, January 1-December 31, 1978

Description: The susceptibility of nickel-copper alloys to liquid metal embrittlement was studied by Auger spectroscopy. Alloys corresponding to Monel 400 with various levels of additional phosphorous were employed and were given various thermal treatments to control the extent of segregation. Segregation of phosphorous to the boundaries, with accompanying decreases in copper and nickel concentrations, greatly reduces susceptibility to intergranular embrittlement by mercury.
Date: January 1, 1978
Creator: Stein, D. F.; Heldt, L. A. & Funkenbusch, A. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Surface impurity studies in the ISX-A tokamak

Description: The Impurity Study Experiment (ISX-A) was a tokamak designed to study impurity sources, plasma-wall interactions, impurity behavior within the plasma, and related phenomena. An Auger electron spectrometer, attached to the tokamak by means of a UHV sample transfer system, has been the primary tool used for surface studies of the first wall. Stainless steel samples positioned at the wall edge were used to follow the progressive ''cleanup'' of the torus wall. Cleaning consisted of low energy hydro… more
Date: January 1, 1978
Creator: Emerson, L. C.; Clausing, R. E. & Heatherly, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Versatile UHV sample transfer system

Description: A vacuum transfer system has been developed that allows samples to be inserted from air into an Auger analyzer. Following an initial analysis they may then be moved to and from a separate vacuum chamber for other studies. The system is constructed of standard UHV components and is unlimited with respect to the transfer distance. All-metal sealed valves isolate the various chambers so that the vacuum integrity of each is maintained. The sample size is limited only by the smallest constriction wi… more
Date: January 1, 1978
Creator: Clausing, R. E.; Heatherly, L. & Emerson, L. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Long-term changes in the surface conditions of PLT

Description: Long-term changes in the surface conditions of the PLT vacuum vessel wall have been monitoried by the periodic analysis of a variety of sample substrates (stainless steel, alumina, silicon), exposed to PLT discharges for periods of up to several months and subsequently removed for analysis by Auger electron spectroscopy (AES), photoelectron spectroscopy (ESCA), ion backscattering, nuclear reaction analysis, secondary ion mass spectrometry (SIMS), and scanning electron microscopy. Samples expose… more
Date: June 1, 1978
Creator: Cohen, S.A.; Dylla, H.F.; Rossnagel, S.M.; Picraux, S.T.; Borders, J.A. & Magee, C.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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