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A Thermal Type Flow Meter for Low Flow Rates of Anhydrous Hydrofluoric Acid

Description: Report discussing a thermal type flow meter which was adapted for metering anydrous hydrofluoric acid at low flow rates. Corrosive gases, which are not appropriate for handling in standard type rotameters or orifice meters, are also suitable for this thermal type flow meter.
Date: June 24, 1946
Creator: Johnsson, Karl Otto; Peed, W. F. & Clewett, G. H.
Partner: UNT Libraries Government Documents Department

Chambers Works Process for the Manufacture of Fluorine in East Area Carbon Anode Cells (M.W.38.0)

Description: Historical: This process is based on experimental work done in Jackson Laboratory, Send Works, Blue Products, and East Area. It supersedes the Tentative Chambers Works Process for the Manufacture of Fluorine Using Carbon Anode Units, dated December 2, 1943.
Date: January 18, 1948
Creator: E. I. du Pont de Nemours & Company
Partner: UNT Libraries Government Documents Department

Separation of Metal Ions by Anion Exchange in Mixtures of Hydrochloric Acid and Hydrofluoric Acid

Description: Distribution coefficients were determined for the adsorption of more than 40 elements on anion-exchange resins from mixtures of HCl (0.1 to 12M) and HF (0.1-8M). Two resins, Dowex 1 x 10, 200 to 400 mesh and Dowex 1 x 4, 100 to 200 mesh, were used. Distribution coefficients were also determined for the adsorption of many elements on both resins from 0.1 to 12M HCl and 0.1 to 12M HF. Anion exchange in the presence of HF was found useful for separating impurities from various materials for their subsequent determination, and specific procedures used in our spectrochemical laboratory for this purpose are outlined. The results of a literature search on the use of anion exchange in hydrofluoric acid and fluoride-containing media are presented in an extensive bibliography.
Date: December 1978
Creator: Faris, J. P.
Partner: UNT Libraries Government Documents Department

A new device for filtering hydrofluoric acid and other strong acids. Information report

Description: During the course of a research problem involving hydrofluoric acid it became necessary to filter concentrated hydrofluoric solutions to remove various solid materials. The search for a suitable filter media finally led to the use of a commercially manufactured plastic material known as ``Sponge Teflon`` (polytetrafluoroethylone) which is produced by the DuPont Company. This material, which comes in 1/8 in. sheets, is used primarily as a gasket material in acid lines, and is impervious to all acids, including hydrofluorle acid.
Date: July 9, 1948
Creator: Bell, R.
Partner: UNT Libraries Government Documents Department

CORROSION ASSOCIATED WITH HYDROFLUORINATION IN THE OAK RIDGE NATIONAL LABORATORY FLUORIDE VOLATILITY PROCESS

Description: Studies carried out on corrosion associated with the hydrofluorination- dissolution phase in the fused-salt Fluoride Volatility Process are summarized. Corrosion for hydrofluorination-dissolver vessels used in bench-scale and semiworks-scale process development at ORNL is discussed. The results of a study on construction materials for the dissolution phase are presented. Corrosion studies at ANL are described for comparison purposes. A full-size hydrofluorinator dissolver is described. (M.C.G.)
Date: November 15, 1961
Creator: Goldman, A.E. & Litman, A.P.
Partner: UNT Libraries Government Documents Department

Buffered Electropolishing – A New Way for Achieving Extremely Smooth Surface Finish on Nb SRF Cavities to be Used in Particle Accelerators

Description: Future accelerators require unprecedented cavity performance, which is strongly influenced by interior surface nano-smoothness. Electropolishing (EP) is the technique of choice to be developed for high-field superconducting radio frequency (SRF) cavities. Electrochemical impedance spectroscopy (EIS) and related techniques point to the electropolishing mechanism of Nb in a sulphuric and hydrofluoric acid electrolyte controlled by a compact surface salt film under F- diffusion-limited mass transport control. These and other findings are guiding a systematic characterization to form the basis for cavities process optimization.
Date: May 1, 2009
Creator: Hui Tian, Charles Reece, Michael Kelley
Partner: UNT Libraries Government Documents Department

Basic Electropolishing Process Research and Development in Support of Improved Reliable Performance SRF Cavities for the Future Accelerator

Description: Future accelerators require unprecedented cavity performance, which is strongly influenced by interior surface nanosmoothness. Electropolishing is the technique of choice to be developed for high-field superconducting radiofrequency cavities. Electrochemical impedance spectroscopy (EIS) and related techniques point to the electropolishing mechanism of Nb in a sulfuric and hydrofluoric acid electrolyte of controlled by a compact surface salt film under F- diffusion-limited mass transport control. These and other findings are currently guiding a systematic characterization to form the basis for cavity process optimization, such as flowrate, electrolyte composition and temperature. This integrated analysis is expected to provide optimum EP parameter sets for a controlled, reproducible and uniform surface leveling for Nb SRF cavities.
Date: May 1, 2009
Creator: H. Tian, C.E. Reece,M.J. Kelley
Partner: UNT Libraries Government Documents Department

DISSOLUTION OF ZIRCONIUM AND ZIRCALOY-2 IN NITRIC-HYDROFLUORIC ACID MIXTURES AT REFLUX TEMPERATURES

Description: BS>The initial rate constants were obtained for zirconium and Zircaloy-2 dissolution at reflux temperatures in nltric--hydrofluoric acid mlxtures. Variation of the nitric acid concentration in these solutions had very little effect on the initial dissolution rate, except for the change in the reflux temperature. The nitric acid concentration exhibited an appreciable effect on the average dissolution rate over longer periods of time. An empirical treatment of the rates over extended periods is presented. The maximum attainable rates for zirconium dissolution, adjusted to an initial lM hydrofluoric acid concentration, were determined at lower temperatures. Stability of resultant Zircaloy-2 dissolver solutions is reported for both nitric--hydrofluoric acid mixtures and nitric--oxalic--hydrofluoric acid mixtures. Possible reactions and some analyses of off-gases from these dissolutions are given. (auth)
Date: September 1, 1959
Creator: Vander Wall, E.M. & Whitener, E.M.f Bauer, D.L.
Partner: UNT Libraries Government Documents Department

INHIBITION OF HNO$sub 3$-HF CORROSION OF TYPE 304-L STAINLESS STEEL WITH Al(NO$sub 3$)$sub 3$/center dot/9H$sub 2$O

Description: To prevent corrosion of equipment by nitric acid hydrofluoric acid mixture, aluminum nitrate nonohydrate is added to tie up the fluoride, either as aluthinum fluoride or a tight complex. It was found that a solution of nitric acid, hydrofluoric acid, and aluthinum nitrate nonohydraie in which the hydrofluonic acid - aluminum nitrate nonohydrate molar ratio is 3, did not show serious corrosive attack on the 300-series stainless steel. (J.E.D.)
Date: November 18, 1957
Creator: Walker, W.L.
Partner: UNT Libraries Government Documents Department

Improvement of Laser Damage Resistance and Diffraction Efficiency of Multilayer Dielectric Diffraction Gratings by HF-Etchback Linewidth Tailoring

Description: Multilayer dielectric (MLD) diffraction gratings for Petawatt-class laser systems possess unique laser damage characteristics. Details of the shape of the grating lines and the concentration of absorbing impurities on the surface of the grating structures both have strong effects on laser damage threshold. It is known that electric field enhancement in the solid material comprising the grating lines varies directly with the linewidth and inversely with the line height for equivalent diffraction efficiency. Here, they present an overview of laser damage characteristics of MLD gratings, and describe a process for post-processing ion-beam etched grating lines using very dilute buffered hydrofluoric acid solutions. This process acts simultaneously to reduce grating linewidth and remove surface contaminants, thereby improving laser damage thresholds through two pathways.
Date: October 28, 2010
Creator: Nguyen, H T; Larson, C C & Britten, J A
Partner: UNT Libraries Government Documents Department

Conversion of Oxyfluoride Based Coated Conductors

Description: Direct measurements of HF pressure in equilibrium with the film during the BaF2 process are sorely needed. It is the HF partial pressure that governs the rate at which the film composition is changing and is, therefore, an important factor in controlling the composition/time trajectory of the film. Establishing the composition/time trajectory of both MOD-derived and e-beam derived films for a given set of conditions is another goal for the project. These studies will provide a fundamental understanding of the ex situ process for producing coated conductors.
Date: November 1, 2006
Creator: Wesolowski, Dan
Partner: UNT Libraries Government Documents Department

CORROSION OF STAINLESS STEEL IN HNO$sub 3$-HF SOLUTIONS

Description: Studies were made on the safe handling of HHO/sub 3/-HF solutions in 304 L and 309SCb stainless-steel equipment under carefully controlled conditions. The corrosion behavior of both wrought and welded 304L and 309SCb was investigated in various HNO/sub 3/--HF solutions, ranging in HNO/sub 3/ concentration from 0 to 10.0 M and HF concentration from 0.01 to 1.5 M, at temperatures from 24 deg C to the boiling point. (auth)
Date: July 1, 1960
Creator: Kranzlein, P.M.
Partner: UNT Libraries Government Documents Department

Prediction of release-etch times for surface-micromachined structures

Description: A one-dimensional model is presented which describes the release-etch behavior of sacrificial oxides in aqueous HF. Starting from first principles and an empirical rate law, release etch kinetics are derived for primitive geometries. The behavior of complex three-dimensional structures is described by joining the solutions of constituent primitives and applying appropriate boundary conditions.The two fitting parameters, k{sub 1} and k{sub 2}, are determined from the simplest structure and describe the more complex structures well. Experimental validation of the model is presented with data for all of the geometries and four types of sacrificial oxides.
Date: May 1, 1997
Creator: Eaton, W.P.; Jarecki, R.L. & Smith, J.H.
Partner: UNT Libraries Government Documents Department

Insensitive HE EOS

Description: A typical insensitive high explosive such as LX-17 has a large carbon-content and produces hydrogen fluoride (HF) as a detonation product. It is also characterized by slow energy release as indicated by a large curvature of the detonation front. We analyze these new physics issues which are needed to predict the performance of a insensitive high explosive. (U)
Date: December 1, 1997
Creator: Ree, F.H.; Viecelli, J. & van Thiel, M.
Partner: UNT Libraries Government Documents Department

Depleted uranium plasma reduction system study

Description: A system life-cycle cost study was conducted of a preliminary design concept for a plasma reduction process for converting depleted uranium to uranium metal and anhydrous HF. The plasma-based process is expected to offer significant economic and environmental advantages over present technology. Depleted Uranium is currently stored in the form of solid UF{sub 6}, of which approximately 575,000 metric tons is stored at three locations in the U.S. The proposed system is preconceptual in nature, but includes all necessary processing equipment and facilities to perform the process. The study has identified total processing cost of approximately $3.00/kg of UF{sub 6} processed. Based on the results of this study, the development of a laboratory-scale system (1 kg/h throughput of UF6) is warranted. Further scaling of the process to pilot scale will be determined after laboratory testing is complete.
Date: December 1, 1994
Creator: Rekemeyer, P.; Feizollahi, F.; Quapp, W.J. & Brown, B.W.
Partner: UNT Libraries Government Documents Department

The Uptake of Hydrogen Fluoride by a Forest

Description: A mathematical model of hydrogen fluoride (HF) deposition and accumulation of fluoride in a Eucalyptus rostrata forest has been developed. The model is based on tree physiology and meteorological principles. The data base for the model was derived from a literature survey of the physiological characteristics of E. rostrata and similar eucalyptus species and from current knowledge of meteorological processes in plant canopies.
Date: December 18, 1980
Creator: Murphy, C.E. Jr.
Partner: UNT Libraries Government Documents Department