Device for determining parameters of tape superconductors

FIELD: electricity.

SUBSTANCE: device for determining the parameters of tape superconductors includes a generator, a frequency-setting element of the generator, a coil connected to the generator, a receiver, a frequency-assigning element of the receiver and a coil connected to the receiver; the coils of the generator and receiver are located with a gap allowing for placement between the coils of the tape superconductor, and the frequencies bandwidth of the frequency-specifying elements of the generator and receiver coincide not less than half the bandwidth of the frequency-assigning element having a smaller bandwidth.

EFFECT: ensuring the possibility of high accuracy and reproducibility of measurement results.

13 cl, 2 dwg

 



 

Same patents:

FIELD: electricity.

SUBSTANCE: semiconductor gas sensor contains the housing 1 of the reactionary chamber 2 made of stainless steel. The housing 1 from the end face is enclosed by the mesh 3 from wire with the diameter 0.03…0.05 mm with the mesh width 0.05…0.07 mm from stainless steel. The spherical semiconductor gas-sensitive element 5 by means of wires of the heater 6 and the measuring conductor 7 is installed in the housing 1 at the centre of the reactionary chamber 2 on the contact conductors 4. Inside the semiconductor gas-sensitive element 5 the heater 6 is located which is designed as a cylindrical spring inside which along its axis and along the diameter of the spherical semiconductor element 5 the direct measuring conductor 7 is placed. The heater 6 and the measuring conductor 7 of the gas-sensitive elements are made from platinum wire with the diameter 0.015…0.03 mm. The heater is implemented by 2…8 rounds of this wire with the diameter of rounds 0.3…0.6 mm. The space around the direct measuring conductor 7 and inside the cylindrical spring of the heater 6 is filled with gas-sensitive compound of SnO2 around which (and around the heater 6) the spherical porous and gas-sensitive layer 5 of In2O3 is provisioned; the external diameter of which is 0.8…0.9 of mm.

EFFECT: improvement of sensitivity, improvement of mechanical strength, long-term stability, response time and resistance to external factors.

8 dwg, 4 tbl

FIELD: measurement equipment.

SUBSTANCE: invention relates to devices for investigation of superconductors with the help of electric and magnetic means. Two inductance coils are installed in the device body. Axes of coils are aligned in parallel to each other and the surface of the sample placed between the coils. To reduce scattering field of the primary coil and to increase the value of signal fall during transition into superconducting condition, the inductance coils are made with a rectangular cross section and installed with a smaller side of a rectangle in parallel to the sample surface. A mechanism to adjust and fix the distance between the sample and the surface of the cryoagent provides for elimination of impact of convection vapours near the cryoagent surface. The device body is made of two halves. The sample of the superconductor is installed in the plane of the body joint to ensure accurate fixation of superconductor position relative to inductance coils and cryoagent surface.

EFFECT: invention makes it possible to ensure high accuracy of measurement of temperature parameters of superconductors.

5 cl, 5 dwg

FIELD: electricity.

SUBSTANCE: determination method of electrical resistivity for melts wherein a melting pot with melt is suspended coaxially in a cylindrical electric oven at the lower end in the resilient wire head while the upper end of resilient wire is fixed in the fixation unit. At that, before melt testing, length of the resilient wire head is changed by blocking the upper end of resilient wire in regard to the fixation unit. The device intended for determination of electrical resistivity for melts comprises a melting pot with melt is suspended coaxially in a cylindrical electric oven at the lower end in the resilient wire head while the upper end of resilient wire is fixed in the fixation unit. At that a clamp and a pin are introduced to it additionally; the pin is fixed non-coaxially in the fixation unit, the clamp is fixed at the pin, it may be moved along the pin and has the facility for fixation in the clamp of the resilient wire upper end.

EFFECT: reducing time for experiments and their simplification during determination of electric resistivity for different melts in case of their change.

2 cl, 2 dwg

FIELD: metallurgy.

SUBSTANCE: disclosed is an apparatus for mounting an electric heater in an electric furnace, having at least two connecting elements of the electric heater which are current leads, a lower flange of the electric furnace having at least two flange attachment lugs which are also current leads and at least two bolt connections. Each of the flange attachment lugs has a wedge-shaped depression, the wedge-shaped depression of each flange attachment lug holding at least one connecting element of the electric heater. The apparatus further includes at least two wedge-shaped fixing elements, at least one of which is placed in the wedge-shaped depression of each of the flange attachment lugs, and the bolt connection grips the wedge-shaped fixing elements of the connecting elements of the electric heater in the flange attachment lugs.

EFFECT: faster and easier replacement of the electric heater, simple and cheap experiments.

3 dwg

FIELD: measurement equipment.

SUBSTANCE: angle of sample rotation is determined in a rotary magnetic field developed by a magnetic assembly in the form of three coils of a three-phase stator, they measure current values, by values of the rotation angle and current they determine specific electric resistance, at the same time measurement of current in one of coils is carried out by means of a multimeter, and zero values of current in any coil are used for alarm on violation of magnetic field parameters. A device for realisation of the method includes a source of a rotary magnetic field with a magnetic system in the form of three coils of a three-phase stator, current sensors, connected to coils, and a computer, an additional current sensor, a multimeter and an alarm device, comprising three subtracting devices, a summator, a threshold element, an optical indicator, inlets of the multimeter are connected with an additional current sensor, the outlet of the multimeter is connected with one of the computer inlets, inlets of each subtracting device are connected to outlets of two current sensors, connected to coils, outlets of subtracting devices are connected to inlets of the summator, the outlet of which via the threshold element is connected with the optical indicator, the outlet of the threshold element is the outlet of the alarm device and is connected with the other inlet of the computer.

EFFECT: provision for reduction of measurement time, simplified experiment with preservation of required accuracy.

5 cl, 1 dwg

Hydrogen detector // 2525643

FIELD: measurement equipment.

SUBSTANCE: invention relates to analysis of materials, in particular, for detection of hydrogen content, and may be used in manufacturing of hydrogen gas analysers in space engineering, motor industry, chemical industry, etc. Substance of the invention: a resistive sensor of hydrogen concentration is proposed, comprising a hydrogen-sensitive element made in the form of a thin-film resistor, comprising in a material at least palladium oxide and a heating element that heats the hydrogen-sensitive element. The hydrogen-sensitive element may be made of silver-palladium resistive paste. The sensor may be made in accordance with a simple and cheap technology widely used in the industry.

EFFECT: creation of a miniature hydrogen detector to detect both atomic and molecular hydrogen, making it possible to perform qualitative and quantitative measurements.

2 cl, 1 dwg, 1 ex

FIELD: instrumentation.

SUBSTANCE: proposed method uses thermo-catalytical sensor with working element and comparator arranged in reaction chamber with diffusion feed of analysed medium. Said working element and comparator are interconnected in series and connected to DC stabiliser controlled by external signal. With instrument switched on, circuit current is adjusted to set preset initial voltage at comparator whereat working element exceeds that of methane complete oxidation start temperature. Thereafter, circuit current is fixed and kept permanent unless instrument switch-off. Working element initial voltage is measured and memorised. Low concentrations of methane are defined using the working element voltage as an output signal. At a time, comparator voltage is controlled unless it reaches preset limit to terminate measurement of voltage at comparator. Voltage at comparator is used as output signal to define methane concentration unless said comparator returns to limit magnitude. Proposed device comprises DC stabiliser controlled by external signal, thermo-catalytical sensor with working element and comparator connected in series, and processor connected via ADC with said sensor to control DC stabiliser to measure voltages at working element and comparator and to process output signals.

EFFECT: expanded range of measurements, higher accuracy.

3 cl, 1 dwg

FIELD: instrument making.

SUBSTANCE: semiconductor gas sensor comprises a body 1 of a reaction chamber 2 made from corrosion-resistant steel. The body 1 closed at the end with a net 3 from stainless steel with wire of diameter 0.03-0.04 mm and pitch of 0.06-0.08 mm. In the body 1 in the centre of the reaction chamber 2 on contact conductors 4 there is a ball-shaped semiconductor sensitive element 5 with the help of wires of a heater 6 and a metering conductor 7. Inside the semiconductor gas sensitive element 5 there is a heater 6 in the form of a cylindrical spring, inside of which along its axis and the diameter of the ball-shaped semiconductor element 5 there is a straight metering conductor 7. The heater 6 and the metering conductor 7 of the gas sensitive element 5 are made of a platinum wire with diameter of 0.01-0.02 mm, the heater 6 has 2-7 turns of the wire, the ball-shaped semiconductor gas sensitive element 2 has the diameter of 0.4-0.8 mm and is made of the mixture of tin oxide SnO2: 5-95 wt % and indium oxide In2O3: 5-95 wt %.

EFFECT: higher sensitivity of a semiconductor gas sensor to low concentrations of gas, development of a simple, reliable, comparatively cheap and efficient sensor, capable of long-term operation in non-serviced mode.

7 dwg, 3 tbl

FIELD: machine building.

SUBSTANCE: method involves determination of polytherms of those properties, for example kinematic viscosity, molten metal so that values of properties are obtained in the form of electric signals, which are displayed on one of the multichannel display channels. At that, polytherm values of molten metal are supplied to differentiator inlet; differentiated signals, which are displayed on the other channel of the multichannel display, are picked up from its outlet. Then, differentiated signals are supplied to a comparison unit, the output signals of which are supplied to an alarm unit inlet and the third channel of the multichannel display, as well as to the adder inlet, from the outlet of which the signals are supplied to the fourth channel of multichannel display and alarm unit.

EFFECT: obtaining additional results and more reliable information, evaluation accuracy of abnormalities on polytherms, and providing the possibility of evaluating the experiment results by semiskilled personnel.

2 cl, 3 dwg

FIELD: construction.

SUBSTANCE: method consists in periodical registration of temperature in process of item reinforcement heating by means of sending of an electric current through it and subsequent heat exchange. Reinforcement condition and tightness of its embedment in the concrete of the checked item are determined by characteristics of temperature field distribution on the item surface and speed of temperature variation in specific zones (points).

EFFECT: higher efficiency and validity of check results for assessment of reinforcement condition.

4 cl, 8 dwg

FIELD: the invention refers to analytical chemistry particular to determination of general hydrogen in uranium dioxide pellets.

SUBSTANCE: the installation has an electrode furnace with feeding assembly , an afterburner, a reaction tube with calcium carbide, an absorption vessel with Ilovay's reagent for absorption of acetylene, a supply unit. The afterburner of hydrogen oxidizes hydrogen to water which together with the water exuding from pellets starts reaction with carbide calcium. In result of this equivalent amount of acetylene is produced. The acetylene passing through the absorption vessel generates with Ilovay's reagent copper acietilenid which gives red color to absorption solution. According to intensity of color of absorption solution the contents of general hydrogen are determined.

EFFECT: simplifies construction of the installation, increases sensitivity and precision of determination of the contents of hydrogen in uranium dioxide pellets.

2 cl, 1 dwg

FIELD: analytical chemistry; analysis of gas mixtures.

SUBSTANCE: according to method of measuring concentration of gas impurity in air, volt-ampere characteristic I (U) is chosen as electrical characteristic. Preliminary calibration is carried out by placing detector in clean air and in gas sample which has known amount of impurity of foreign gas. Voltage and/or temperature of heating of gas-sensitive film are changed till nonlinear part emerges at volt-ampere characteristic. Voltage Uc is determined at which voltage volt-ampere characteristic changes to non-linear law. Moreover calibration is carried out by measuring volt-ampere characteristics inside voltage area being lower than Uc. Concentration dependence of changes in conductivity of detector in gas sample is determined relatively conductivity in clean air at initial part of volt-ampere characteristic within voltage area being lower than Uc. Changes in conductivity of detector are measured in clean air relatively to conductivity of detector when impurity is present. Concentration of impurity in air is found from value of the relation. Permanent presence of medium of comparison (clean air) is not necessary and all the measurements can be made by means of single detector.

EFFECT: improved precision of measurement.

2 cl, 11 dwg

FIELD: physics.

SUBSTANCE: method of determining hydrogen concentration in the presence of gaseous impurities involves measurement of an electrical signal at the output of a semiconductor sensor with a metal oxide sensitive layer while heating it to a given temperature. The value of conductivity of the sensitive layer of the semiconductor sensor is determined from the value of this signal, stored, compared with a calibration value and hydrogen concentration is determined. The signal at the output of the semiconductor sensor is continuously measured, while periodically heating the sensor to temperature T1 and cooling to temperature T2. The time derivative of the conductivity of the sensitive layer of the sensor is determined during the interval between the end of the heating to T1 and the end of cooling to T2. The value of conductivity, which is a function of gas concentration, is determined. Presence and number of local minimums on the graph of conductivity of the sensitive layer versus time in the interval between the end of heating and the end of cooling is then determined. If there are two local minimums, the electrical signal at the output of the semiconductor sensor is measured in the time interval between the first and last local minimums, in which the absolute value the time derivative of conductivity is minimal. If there is one local minimum, the electrical signal at the output of the semiconductor sensor is measured in the time interval between the end of heating and the last local minimum, in which the absolute value of the time derivative of conductivity is minimal, and from the value of the measured electrical signal, the value of conductivity of the sensitive layer of the semiconductor sensor is determined, from which hydrogen concentration is determined.

EFFECT: increased accuracy and selectivity of determining hydrogen concentration.

3 cl, 2 dwg

FIELD: physics.

SUBSTANCE: invention can be used for monitoring gaseous atmosphere in industrial buildings with dangerous working conditions, particularly for providing for hydrogen explosion safety under the containment shell of a nuclear power plant and explosion-proof compartments. In the hydrogen gas analyser, which has a sensor compartment which can be linked to the monitored volume, the sensor compartment has a sensor and porous or diffusion membrane wall which is selective towards hydrogen. The sensor compartment is filled with hydrogen-sensitive substance with exothermal response. The sensor is made in form of at least one thermocouple or thermistor. The membrane wall is made from shock-resistant material. The sensor compartment has an airtight cartridge with a holding bracket for joining to the monitored volume.

EFFECT: design of a reliable, simple and cheap gas analyser with long service life.

4 cl, 1 dwg

FIELD: physics.

SUBSTANCE: invention can be used when making gas sensors, based on composite semiconductor inorganic materials, as well as during synthesis of equivalent circuit film structures. In the gas-sensitive element, active and capacitive resistance is measured depending on frequency, from which the magnitude and angle of impedance of the equivalent circuit model of the gas-sensitive element are determined; the transfer-function coefficient of the gas-sensitive element is then determined and the electric circuit of the model of the gas-sensitive element is synthesised with determination of values of resistance and capacitance of elements of the circuit model of the analysed gas-sensitive element.

EFFECT: measurements are taken in a wide frequency range, which enables to select that region where values corresponding to the true volume resistance of the sample are measured.

1 dwg

FIELD: construction.

SUBSTANCE: method consists in periodical registration of temperature in process of item reinforcement heating by means of sending of an electric current through it and subsequent heat exchange. Reinforcement condition and tightness of its embedment in the concrete of the checked item are determined by characteristics of temperature field distribution on the item surface and speed of temperature variation in specific zones (points).

EFFECT: higher efficiency and validity of check results for assessment of reinforcement condition.

4 cl, 8 dwg

FIELD: machine building.

SUBSTANCE: method involves determination of polytherms of those properties, for example kinematic viscosity, molten metal so that values of properties are obtained in the form of electric signals, which are displayed on one of the multichannel display channels. At that, polytherm values of molten metal are supplied to differentiator inlet; differentiated signals, which are displayed on the other channel of the multichannel display, are picked up from its outlet. Then, differentiated signals are supplied to a comparison unit, the output signals of which are supplied to an alarm unit inlet and the third channel of the multichannel display, as well as to the adder inlet, from the outlet of which the signals are supplied to the fourth channel of multichannel display and alarm unit.

EFFECT: obtaining additional results and more reliable information, evaluation accuracy of abnormalities on polytherms, and providing the possibility of evaluating the experiment results by semiskilled personnel.

2 cl, 3 dwg

FIELD: instrument making.

SUBSTANCE: semiconductor gas sensor comprises a body 1 of a reaction chamber 2 made from corrosion-resistant steel. The body 1 closed at the end with a net 3 from stainless steel with wire of diameter 0.03-0.04 mm and pitch of 0.06-0.08 mm. In the body 1 in the centre of the reaction chamber 2 on contact conductors 4 there is a ball-shaped semiconductor sensitive element 5 with the help of wires of a heater 6 and a metering conductor 7. Inside the semiconductor gas sensitive element 5 there is a heater 6 in the form of a cylindrical spring, inside of which along its axis and the diameter of the ball-shaped semiconductor element 5 there is a straight metering conductor 7. The heater 6 and the metering conductor 7 of the gas sensitive element 5 are made of a platinum wire with diameter of 0.01-0.02 mm, the heater 6 has 2-7 turns of the wire, the ball-shaped semiconductor gas sensitive element 2 has the diameter of 0.4-0.8 mm and is made of the mixture of tin oxide SnO2: 5-95 wt % and indium oxide In2O3: 5-95 wt %.

EFFECT: higher sensitivity of a semiconductor gas sensor to low concentrations of gas, development of a simple, reliable, comparatively cheap and efficient sensor, capable of long-term operation in non-serviced mode.

7 dwg, 3 tbl

FIELD: instrumentation.

SUBSTANCE: proposed method uses thermo-catalytical sensor with working element and comparator arranged in reaction chamber with diffusion feed of analysed medium. Said working element and comparator are interconnected in series and connected to DC stabiliser controlled by external signal. With instrument switched on, circuit current is adjusted to set preset initial voltage at comparator whereat working element exceeds that of methane complete oxidation start temperature. Thereafter, circuit current is fixed and kept permanent unless instrument switch-off. Working element initial voltage is measured and memorised. Low concentrations of methane are defined using the working element voltage as an output signal. At a time, comparator voltage is controlled unless it reaches preset limit to terminate measurement of voltage at comparator. Voltage at comparator is used as output signal to define methane concentration unless said comparator returns to limit magnitude. Proposed device comprises DC stabiliser controlled by external signal, thermo-catalytical sensor with working element and comparator connected in series, and processor connected via ADC with said sensor to control DC stabiliser to measure voltages at working element and comparator and to process output signals.

EFFECT: expanded range of measurements, higher accuracy.

3 cl, 1 dwg

Hydrogen detector // 2525643

FIELD: measurement equipment.

SUBSTANCE: invention relates to analysis of materials, in particular, for detection of hydrogen content, and may be used in manufacturing of hydrogen gas analysers in space engineering, motor industry, chemical industry, etc. Substance of the invention: a resistive sensor of hydrogen concentration is proposed, comprising a hydrogen-sensitive element made in the form of a thin-film resistor, comprising in a material at least palladium oxide and a heating element that heats the hydrogen-sensitive element. The hydrogen-sensitive element may be made of silver-palladium resistive paste. The sensor may be made in accordance with a simple and cheap technology widely used in the industry.

EFFECT: creation of a miniature hydrogen detector to detect both atomic and molecular hydrogen, making it possible to perform qualitative and quantitative measurements.

2 cl, 1 dwg, 1 ex

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