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The Legendary "White Metal" and its "Ore"

Description: Report concerning stories about claims of a "white metal" extracted from an "ore" found packed around pieces of iron or steel. It includes information about various tests conducted about the validity of these claims and their findings.
Date: December 1925
Creator: Davis, C. W.
Partner: UNT Libraries Government Documents Department

The Performance of Silicon Based Sensor and its Application in Silver Toxicity Studies

Description: The silicon based sensor is able to detect part per trillion ionic silver in 0.0098% hydrofluoric acid based on the open circuit potential (OCP) measurement. The OCP jump of 100 ppt ionic silver solution is up to 120 mV. The complex agent can effectively suppress the ionic silver concentration and suppress the OCP signal. The ability of complex agent to suppress the OCP signal depends on the formation constant of the complex with silver. The complex adsorbed on the sensor surface induces a second OCP jump, the height of the second jump depends on the formation constant of the complex. The MINEQL chemical equilibrium modeling program is used to calculate the ionic silver concentration when complex agent presents, a discrepancy is found between the MINEQL simulation result and the OCP signal of the silicon based sensor. The toxicity of ionic silver to C. dubia is studied parallel to the OCP signal of silicon based sensor. Less toxicity is found when the complex agent is present similar to the OCP signal. Another discrepancy is found between the MINEQL simulation and the toxicity test when MINEQL simulation is used to predict and control the ionic silver concentration. The data from both biosensor C. dubia and silicon based sensor support each other and both are not in agreement with MINEQL simulation prediction.
Date: August 2000
Creator: Peng, Haiqing
Partner: UNT Libraries

Non-cyanide silver plating

Description: Lawrence Livermore National Laboratory (LLNL) and Technic, Inc. have entered into a CRADA (Cooperative Research and Development Agreement) with the goal of providing industry with an environmentally benign alternative to the presently used silver cyanide plating process. This project has been in place for about six months and results are quite promising. The main objective, that of deposition of deposits as thick as 125 um (5 mils), has been met. Property data such as stress and hardness have been obtained and the structure of the deposit has been analyzed via metallography and x-ray diffraction. These results will be presented in this paper, along with plans for future work.
Date: November 7, 1995
Creator: Dini, J.W.
Partner: UNT Libraries Government Documents Department

Synthesis, structure, and reactivity of high oxidation state silver fluorides and related compounds

Description: This thesis has been largely concerned with defining the oxidizing power of Ag(III) and Ag(II) in anhydrous hydrogen fluoride (aHF) solution. Emphasis was on cationic species, since in a cation the electronegativity of a given oxidation state is greatest. Cationic Ag(III) solv has a short half life at ordinary temperatures, oxidizing the solvent to elemental fluorine with formation of Ag(II). Salts of such a cation have not yet been preparable, but solutions which must contain such a species have proved to be effective and powerful oxidizers. In presence of PtF{sub 6}{sup {minus}}, RuF{sub 6}{sup {minus}}, or RhF{sub 6}{sup {minus}}, Ag(III) solv effectively oxidizes the anions to release the neutral hexafluorides. Such reactivity ranks cationic Ag(III) as the most powerfully oxidizing chemical agent known as far. Unlike its trivalent relative Ag (II) solv is thermodynamically stable in acid aHF. Nevertheless, it oxidizes IrF{sub 6}{sup {minus}} to IrF{sub 6} at room temperature, placing its oxidizing potential not more than 2 eV below that of cationic Ag(III). Range of Ag{sup 2+} (MF{sub 6}{sup {minus}}){sub 2} salts attainable in aHF has been explored. An anion must be stable with respect to electron loss to Ag{sup 2+}. The anion must also be a poor F{sup {minus}} donor; otherwise, either AgF{sup +} salts or AgF{sub 2} are generated.
Date: May 1, 1995
Creator: Lucier, G.M.
Partner: UNT Libraries Government Documents Department

Application of Silver Chloride in Investigations of Elasto-Plastic States of Stress

Description: Note presenting a description of the use of silver chloride as a material for photoelastic stress analysis, which offers the possibilities of studying both elastic and plastic states of stress in a crystalline metallike material on either a microscale or macroscale. In order to use it, however, it is necessary to relate the stress state quantitatively with the observed relative retardation and extinction angle.
Date: November 1953
Creator: Goodman, L. E. & Sutherland, J. G.
Partner: UNT Libraries Government Documents Department

ANSWERS TO QUESTIONS ON OFF-GAS TREATMENT. Eurochemic Assistance Program: Comments by HAPO, dated March 12, 1959, on Questions by E.L. Nicholson

Description: Information relative to the performance and operation of silver reactors is presented. The information is given as answers to questions submitted in the USAECEurochemic Company cooperative program. The answers to 8 questions are presented along with the basis for comments. (J.R.D.)
Date: March 26, 1959
Creator: Bupp, L. P.
Partner: UNT Libraries Government Documents Department

Spreading of liquid Silver and Silver-Molybdenum alloys on molybdenum substrates

Description: The spreading of liquid Ag and Ag-Mo alloys on molybdenum substrates has been studied using a drop-transfer setup. Even though initial spreading velocities as fast as {approx}1 m/s have been recorded in some experiments, a large variation in the spreading dynamics has been observed, and there is no unique relationship between the contact angle and the spreading velocity. This can be attributed to the formation of ridges at the triple junction, the movement of which controls spreading. The fastest spreading rates are consistent with results reported for low temperature liquids; these can be described using a molecular-kinetic model. Spreading kinetics and final contact angles were similar for pure silver and silver-molybdenum liquids.
Date: August 1, 2002
Creator: Rauch, Nicole; Saiz, Eduardo & Tomsia, Antoni P.
Partner: UNT Libraries Government Documents Department

Claude Monet

Description: No Description Available.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: 1926
Creator: Muray, Nickolas
Partner: UNT College of Visual Arts + Design

Photogram

Description: No Description Available.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: 1923~
Creator: Moholy-Nagy, László
Partner: UNT College of Visual Arts + Design

Untitled (Sprinter)

Description: No Description Available.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: 1890~/1900~
Creator: Marey, Jules Etienne & Demeny, Georges
Partner: UNT College of Visual Arts + Design