Preparation of Fine Spherical Particles of Precursors for Yttrium Barium Cuprate Superconductors via thermal decomposition of triethylene glycol solution

1994 ◽  
Vol 620 (11) ◽  
pp. 1915-1920 ◽  
Author(s):  
Holger Stephan ◽  
Karsten Gloe ◽  
Ulrich Wiesner ◽  
Gernot Krabbes
Keyword(s):  
Thermal Decomposition ◽  
Cuprate Superconductors ◽  
Triethylene Glycol ◽  
Spherical Particles ◽  
Yttrium Barium Cuprate ◽  
Yttrium Barium ◽  
Glycol Solution

Adsorption of water molecules on yttrium barium cuprate superconductors

2000 ◽  
Vol 45 (9) ◽  
pp. 1147-1153 ◽  
Author(s):  
B. M. Gorelov ◽  
D. V. Morozovskaya ◽  
V. M. Pashkov ◽  
V. A. Sidorchuk
Keyword(s):  
Cuprate Superconductors ◽  
Water Molecules ◽  
Yttrium Barium Cuprate ◽  
Adsorption Of Water ◽  
Yttrium Barium

scholarly journals Yttrium-barium cuprate superconductors on titanium and rutile substrates

2008 ◽  
Vol 97 ◽  
pp. 012090
Author(s):  
C Mitterbauer ◽  
G Gritzner ◽  
N Hörhager ◽  
H W Weber
Keyword(s):  
Cuprate Superconductors ◽  
Yttrium Barium Cuprate ◽  
Yttrium Barium

INTERGRANULAR FLUX TRAPPING EFFECTS IN YTTRIUM BARIUM CUPRATE SUPERCONDUCTORS

1989 ◽  
Vol 03 (05) ◽  
pp. 437-446 ◽  
Author(s):  
G.J. RUSSELL ◽  
D.N. MATTHEWS ◽  
K.N.R. TAYLOR ◽  
B. PERCZUK
Keyword(s):  
Magnetic Field ◽  
Applied Field ◽  
Cuprate Superconductors ◽  
Weak Link ◽  
Anomalous Behavior ◽  
Granular System ◽  
Electrical And Magnetic Properties ◽  
Yttrium Barium Cuprate ◽  
Yttrium Barium ◽  
Circulating Currents

Simultaneous measurements of the magnetic field dependence of the critical current density and the magnetization of yttrium barium cuprate superconductors have shown the presence of significant residual magnetic fluxes after the applied field has been reduced to zero. This trapped flux can be sufficient to leave the material in the mixed state and results in anomalous behavior of the observed electrical and magnetic properties. The flux appears to be associated with a magnetic field component threaded through the intergranular regions, whose motion is inhibited by circulating currents flowing in the granular system surrounding the field and preserved through the weak-link coupling. Once this coupling is destroyed, the field can move more freely. For a current-carrying sample in zero applied field, the Lorentz force due to the residual field causes the flux to leak from the sample, leading to the appearance of a voltage along the specimen.

Completely Textured Yttrium Barium Cuprate Superconductors

1989 ◽  
pp. 253-257
Author(s):  
D. N. Matthews ◽  
A. Bailey ◽  
S. Town ◽  
G. Alvarez ◽  
G. J. Russell ◽  
...  
Keyword(s):  
Cuprate Superconductors ◽  
Yttrium Barium Cuprate ◽  
Yttrium Barium

Preparation of YBa2Cu3O7−x precursors from a fused eutectic of sodium and potassium hydroxides

1989 ◽  
Vol 4 (6) ◽  
pp. 1307-1311 ◽  
Author(s):  
Nicholas Coppa ◽  
Daniel H. Nichols ◽  
John W. Schwegler ◽  
J. E. Crow ◽  
G. H. Myer ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Potassium Hydroxide ◽  
Product Formation ◽  
Mechanical Grinding ◽  
Reaction Conditions ◽  
Fine Powders ◽  
Yttrium Barium ◽  
Sodium And Potassium

A method for preparing YBa2Cu3O7−x from the simultaneous thermal decomposition of the nitrates of yttrium, barium, and copper in an anhydrous fused eutectic of sodium and potassium hydroxide is described. This method eliminates the need for any mechanical grinding or the introduction of carbon containing anions. Products formed are fine powders (∼1 μm) having mole ratios 1.00Y:2.00Ba:3.06Cu.X-ray diffraction analyses reveal that the initial products are Y(OH)3, BaO2, and CuO, which when air calcinated/oxygen annealed at 900–950 °C form the superconducting YBa2Cu3O7−x A mechanism is postulated for product formation as a function of reaction conditions.

THE ACTIVATION OF PURIFIED HUMAN PLASMINOGEN IN SOLUTIONS OF ETHYLENE GLYCOLS

1963 ◽  
Vol 41 (1) ◽  
pp. 889-895 ◽  
Author(s):  
Phyllis S. Roberts
Keyword(s):  
Methyl Ester ◽  
Ethylene Glycol ◽  
Diethylene Glycol ◽  
Room Temperature ◽  
Fast Rate ◽  
Triethylene Glycol ◽  
Ethylene Glycols ◽  
Human Plasminogen ◽  
Glycol Solution ◽  
Rate Of Accumulation

Ethylene glycols have been found to allow activation of purified preparations of human plasminogen. The activity of the enzyme formed, plasmin, was measured using TAMe (p-toluene-sulphonyl-L-arginine methyl ester) as a substrate. In 50% (v/v) solutions of these compounds at pH 7.6 and 30 °C, plasmin accumulated faster in diethylene and triethylene glycols than in glycerol, but in ethylene glycol no plasmin was found. When lower concentrations of ethylene glycol (from zero to 50%) and shorter times of incubation were used, plasmin was found. With equimolar solutions (4.3 M) of glycerol and the three glycols, only diethylene glycol showed a fast rate of accumulation of plasmin. A 50% triethylene glycol solution partially inhibited the rate of spontaneous activation but stabilized the plasmin formed and therefore enzyme accumulated. At room temperature more plasmin accumulated than at higher temperatures when plasminogen was incubated in 50% triethylene glycol solution, and no plasmin was found when plasminogen was incubated at pH 7.6, 30 °C, in 50% solutions of propylene glycols, several ethers of the ethylene glycols, several polymers of various glycols, and dioxane.

Superconducting fibers from organometallic precursors. Part II: Chemistry and low temperature processing1

1991 ◽  
Vol 6 (5) ◽  
pp. 895-907 ◽  
Author(s):  
Richard M. Laine ◽  
Kay A. Youngdahl ◽  
Richard A. Kennish ◽  
Martin L. Hoppe ◽  
Zhi-Fan Zhang ◽  
...  
Keyword(s):  
Low Temperature ◽  
Organometallic Polymers ◽  
Metal Carboxylate ◽  
Copper Metal ◽  
Metal Carboxylates ◽  
Yttrium Barium Cuprate ◽  
Yttrium Barium ◽  
Organometallic Precursors ◽  
Optimal Approach ◽  
Selection Of

Working principles are developed as guidelines for the selection and/or design of organometallic polymers for processing fiber precursors to metal oxide fibers. These principles form the basis for the selection of metal carboxylate preceramics as an optimal approach to processing yttrium barium cuprate (123) ceramic superconducting fibers. A variety of candidate yttrium, barium, calcium, strontium, bismuth, and copper metal carboxylates were synthesized. Solubility and empirical rheology tests were conducted to screen these compounds to choose spinnable precursor systems. Simple extrusion studies confirmed that THF solutions of mixtures of yttrium, barium, and copper isobutyrates with some quantity of barium 2-ethyl-hexanoates can be used to successfully form 60–70 μm diameter 123 precursor fibers.

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