摘要:
An infrared light-excited light-emitting substance given by the general formula:R1.sub.x R2(.sub.1-x)Ba.sub.z Cl.sub.3+2z where R1 is a rare-earth element, x satisfies the relation 0.01
摘要:
Disclosed herein is an amorphous material in the form of foil for the regenerator, which is prepared by quenching a melt of a rare earth alloy by injection toward the surface of a roll running at a high speed, said alloy being composed of one or more rare earth elements in an amount of 50-99 atomic %, with the remainder being one or more iron family elements. This amorphous material has a large, stable specific heat capacity at very low temperatures.
摘要:
An ultrasonic delay line device has an adjusting circuit for adjusting delay time provided between two terminals at the power input side of an ultrasonic delay line, wherein the adjusting circuit includes a serial connection of a fixed capacitor and a variable resistor connected between said two terminals of the power input side and a fixed coil connected in parallel with the serial connection of the fixed capacitor and the variable resistor.
摘要:
An improved apparatus for preparation of high-melting-point high-toughness metals comprising a reaction chamber in which a halide of said metal is reacted with an active metal and the remaining active metal and the produced active metal halide are vaporized and a condensation chamber in which vapors of the remaining active metal and the active metal halide are condensed is disclosed. The apparatus comprises a reaction chamber and a condensation chamber as described above both of which are provided with a neck having a passage-closing means of the seal pot structure, and the two chambers are placed in parallel in the upright position and are connected with a horizontal connecting duct.
摘要:
A basicity-resistant refractory wherein the substratum includes a surface layer of a composite oxide of which magnesium oxide is the main component, and an oxide as a second component and which forms a high melting point composite oxide with magnesium oxide and iron oxides through reaction with iron oxides in a melt or a calcined mass. The oxide which is the second component may be one or more of titanium oxide, niobium oxide, neodymium oxide, lanthanum oxide, manganese oxide, nickel oxide, and cobalt oxide.
摘要:
A process for preparing compound metal oxides, superconductive compound oxides, is disclosed. The process comprises preparing an aqueous solution containing a predetermined content ratio of chloride, nitrate or acetate of a rare earth metal, an alkaline earth metal and copper, said content ration corresponding to the composition of the object compound metal oxide, adjusting the pH of the solution to 1.5-2.0, adding oxalic acid in an amount such that the concentration of the residual oxalic acid becomes 0.05 M/l-0.1 M/l, collecting the thus formed precipitate and firing it.
摘要:
In an apparatus for preparation of high-melting-point high-toughness metals by reduction of chlorides thereof with an active metal which comprises a heatable and tightly closable reaction chamber, an evacuable and coolable condensation chamber for separating the unreacted active metal and the formed chloride of the active metal from the formed object metal and an intermediate connecting section for communicating and cutting off the two chambers, the improved apparatus which is characterized in that it comprises a seal pot closing means having a funnel and a pot which is closed by introducing a melt of a fusible and vaporizable material and solidifying it therein, is disclosed.
摘要:
A refractory is disclosed which contains integrally sintered magnesia particles forming the skeleton of the refractory and a mineral phase of magnesium orthotitanate (Mg.sub.2 TiO.sub.4) formed between the magnesia particles, thus giving an increased erosion resistance. Preferably, the refractory comprises coarse magnesia particles having an average particle diameter of at least 1 mm or a mixture of coarse magnesia particles having an average particle diameter of at least 1 mm and medium magnesia particles having an average particle diameter of 1 to 0.15 mm and 5 to 50 wt. % of magnesium orthotitanate intervening between the magnesia particles. The refractory not only has an excellent durability in a basic atmosphere, but also has a high strength because of combination of the coarse or medium magnesia particles so that it does not tend to deform and has a high durability against thermal shock.
摘要:
An ultrasonic delay line comprises a delay medium provided with transducers on at least a side surface thereof, an insulating substrate having a frame-like body in which a wiring pattern is print-formed and an opening having substantially the same shape as the outer configuration of the delay medium, the delay medium being fitted in the opening so that an electrode of the transducer is electrically connectable with the wiring pattern, and a packaging member covering at least a part of major surfaces of the insulating substrate and the delay medium so as to secure the two.