CN101408462A - Method and device for measuring ultrasonic wave coal wall temperature - Google Patents

Method and device for measuring ultrasonic wave coal wall temperature Download PDF

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Publication number
CN101408462A
CN101408462A CNA2008101945332A CN200810194533A CN101408462A CN 101408462 A CN101408462 A CN 101408462A CN A2008101945332 A CNA2008101945332 A CN A2008101945332A CN 200810194533 A CN200810194533 A CN 200810194533A CN 101408462 A CN101408462 A CN 101408462A
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China
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pin
ultrasonic
circuit
chip
ultrasonic sensor
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CNA2008101945332A
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Chinese (zh)
Inventor
童敏明
童紫原
付明
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中国矿业大学
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Priority to CNA2008101945332A priority Critical patent/CN101408462A/en
Publication of CN101408462A publication Critical patent/CN101408462A/en

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Abstract

The invention relates to an ultrasonic coal wall temperature measurement method and a device thereof. An ultrasonic sensor is arranged at a designated point of a coal mine, a single-chip microcomputer circuit is utilized to control the ultrasonic sensor to transmit ultrasonic signals, and the sensor also receives the reflected signals and triggers the external interrupt of a single-chip microcomputer by an ultrasonic receiving circuit to obtain the time of flight of the ultrasonic signals between the round trip. On the premise of knowing the coal wall distance, data are processed by the single-chip microcomputer according to a gas constant and an adiabatic exponent of the signal flight environment to obtain the measurement result of the coal wall temperature, and the result is displayed by a digital display. The measurement device is composed of the ultrasonic sensor, the single-chip microcomputer circuit, the ultrasonic transmitting circuit, the ultrasonic receiving circuit and the digital display. The ultrasonic sensor is connected with the ultrasonic transmitting circuit and the ultrasonic receiving circuit simultaneously, an external interrupt port of the single-chip microcomputer circuit is connected with the ultrasonic receiving circuit, and an output interface of the single-chip microcomputer circuit is connected with the digital display.

Description

Measuring ultrasonic wave coal wall temperature method and device

Technical field

The present invention relates to a kind of temperature measuring equipment, especially relate to a kind of measuring ultrasonic wave coal wall temperature method and device.

Background technology

Existing temp measuring method mainly can be divided into two kinds, and a kind of is contact, and a kind of is contactless.Contact type measurement needs enough contact for a long time and reaches thermal equilibrium, and this method often will be destroyed the thermal equilibrium state of testee, and is subjected to the corrosive attack of measured medium.Therefore, to structure, the performance requirement harshness of temperature-sensing element, this method is unfavorable for the measurement of rib temperature.The characteristics that the noncontact method is measured temperature are: do not contact with testee, do not change the Temperature Distribution of testee yet, this method thermometric is more superior, more infrared measurement of temperature as present usefulness, but it is higher owing to coal dust concentration in mine, make infrared reception measure and exist, can not accurately measure than mistake.

Summary of the invention

The objective of the invention is to overcome the deficiency in the prior art, provide that a kind of operating process is simple, the low cost of manufacture of equipment, anti-interference strong and high non-contact type ultrasonic rib thermometry and the device of precision.

Measuring ultrasonic wave coal wall temperature method of the present invention:

A. fixed point is provided with the ultrasonic sensor that a frequency is about 40KHZ under coal mine;

B. adopt single chip circuit control ultrasonic transmit circuit to drive ultrasonic sensor and send the ultrasonic signal that is about 40KHZ, utilize the function of ultrasonic transmit circuit phase inverter, ultrasonic transmit circuit is exported positive and negative 5 volts driving voltage, the work of driving ultrasonic sensor, this ultrasonic sensor receives the ultrasonic signal of reflected back simultaneously, external interrupt by ultrasound wave receiving circuit triggering single chip circuit draws the time delay t between signal;

C. measure between fixed point ultrasonic sensor and the rib apart from l, obtain the signal velocity v of ultrasonic signal on this path by formula v=2l/t;

D. determine coal seam gas law constant R and gas adiabatic exponent K on every side, carry out digital processing, demonstrate the temperature of the rib of surveying through digital indicator by single-chip microcomputer.

Measuring ultrasonic wave coal wall temperature device of the present invention, by ultrasonic sensor, single chip circuit, ultrasonic transmit circuit, ultrasound wave receiving circuit and digital indicator constitute, wherein: ultrasonic sensor is connected with the ultrasound wave receiving circuit with ultrasonic transmit circuit simultaneously, and the external interrupt mouth of single chip circuit is connected with the ultrasound wave receiving circuit, and the output interface of single chip circuit is connected with digital indicator.

The model of described ultrasonic sensor is TCF40-25TR1, and the model of single chip circuit is AT89S52, and the digital indicator model is SM410561K; Described ultrasonic transmit circuit adopts the 74ls04 chip, three input port pins 1 of the phase inverter of chip 74ls04, pin 3, pin 5 link to each other with the P0.0 mouth of single-chip microcomputer simultaneously, wherein the output terminal pin 2 of phase inverter pin 1 input port links to each other with phase inverter input port pin 11, pin 13 simultaneously, wherein the delivery outlet pin 10 of pin 11 links to each other with the positive pole of ultrasonic sensor, and the delivery outlet pin 4 of pin 3 links to each other with the negative pole of ultrasonic sensor with the delivery outlet pin of pin 56 simultaneously; Described ultrasound wave receiving circuit adopts ultrasonic receiving chip CX20106A, and the pin of chip CX20106A 1 connects the positive pole of ultrasonic sensor, and negative pole is by filter capacitor C1 ground connection, is connected the RC series network between pin 2 and the ground; Be connected detection capacitor C 3 between pin 3 and the ground, pin 4 is an earth terminal, insert a resistance R 2 between pin 5 and power supply, meet an integrating capacitor C4 between pin 6 and the ground, pin 7 is the guidance command output terminal, this pin connects a pull-up resistor R3 to power end, and pin 8 is a positive source, and voltage is 4.5~5.5V.

Beneficial effect of the present invention: utilize hyperacoustic propagation characteristic, ultrasound wave has beam because of wavelength is short strong and be easy to the characteristics of concentrating energy by focusing on, in communication process, be not easy disturbed, what the ultrasound wave thermometric adopted is the method for non-cpntact measurement, by under the prerequisite of certain distance, sending ultrasonic signal receives through rib reflected back signal and by same sensor, determine flying over the mistiming of signal by the relation of analyzing between two signals, compare with the temp measuring method of prior art, has the measuring accuracy height, only need a ultrasonic sensor to carry out on-line measurement, its manufacturing cost is lower.Simultaneously, because ultrasonic sensor has good selectivity to signal, ultrasonic signal has stronger penetrability, when transmitting and receiving reflected signal, be subjected to the interference of environmental factor little, can guarantee the precision of measurement, be applicable in the more abominable mine of environmental baseline and carry out temperature survey.Because the outstanding or water bursting in mine of gas goes to toward the omen that the rib temperature variation is arranged, so the detection of rib temperature has important effect to effective forecasting coal mine disaster evil in the mine.

Description of drawings

Fig. 1 is the theory diagram of ultrasound wave temperature measuring equipment of the present invention;

Fig. 2 is the single-chip microcomputer display circuit figure of ultrasound wave temperature measuring equipment of the present invention;

Fig. 3 is ultrasonic transmit circuit figure of the present invention;

Fig. 4 is ultrasound wave receiving circuit figure of the present invention;

Fig. 5 is a single-chip microcomputer main program flow chart of the present invention.

Concrete embodiment

The invention will be further described below in conjunction with the embodiment in the accompanying drawing:

Shown in Figure 1, the ultrasound wave temperature measuring equipment mainly contains single chip circuit, digital indicator, ultrasonic transmit circuit, ultrasound wave receiving circuit and ultrasonic sensor, ultrasonic sensor is connected with the ultrasound wave receiving circuit with ultrasonic transmit circuit simultaneously, and single chip circuit links to each other with ultrasonic transmit circuit, single chip circuit links to each other with the ultrasound wave receiving circuit, and single chip circuit links to each other with digital indicator.Wherein, the model of ultrasonic sensor is TCF40-25TR1, and single chip circuit adopts AT89S52, and the model of digital indicator is SM410561K, the chip for driving of ultrasonic transmit circuit adopts phase inverter 74ls04, and the receiving chip model of ultrasound wave receiving circuit is CX20106A.Single chip circuit is traditional circuit, be provided with two timers in the single-chip microcomputer and be respectively timer 0 and timer 1, it is the 40KHZ square-wave signal that timer 1 allows the P0.0 mouth of single-chip microcomputer produce frequency, after the external port down trigger of single chip circuit, calculate degree of the flying time of ultrasonic signal on the path by timer 0, utilize the acoustic thermometry principle, carry out data processing, draw the measurement result of temperature, show by numeric display unit.

Shown in Figure 2, circuit connection diagram for numeric display unit and single-chip microcomputer, the result who is used for measuring the rib temperature shows by digital indicator, the P1.0 mouth of single-chip microcomputer links to each other with the pin 1 of digital indicator by resistance R 1 among the figure, the P1.1 mouth of single-chip microcomputer links to each other with the pin 2 of digital indicator by resistance R 2, the P1.2 mouth of single-chip microcomputer links to each other with the pin 3 of digital indicator by resistance R 3, the P1.3 mouth of single-chip microcomputer links to each other with the pin 4 of digital indicator by resistance R 4, the P1.4 mouth of single-chip microcomputer links to each other with the pin 5 of digital indicator by resistance R 5, the P1.5 mouth of single-chip microcomputer links to each other with the pin 6 of digital indicator by resistance R 6, the P1.6 mouth of single-chip microcomputer links to each other with the pin 7 of digital indicator by resistance R 7, and the P1.7 mouth of single-chip microcomputer links to each other with the pin 8 of digital indicator by resistance R 8.The RST mouth of single-chip microcomputer links to each other with power supply by pushbutton switch S1, resistance R 13, and the RST mouth of single-chip microcomputer links to each other with power supply by capacitor C 1, and the RST mouth of single-chip microcomputer constitutes the reset circuit of single-chip microcomputer by resistance R 14 ground connection simultaneously.The P2.0 mouth of single-chip microcomputer links to each other with the base stage B1 of triode Q1 by resistance R 12, the P2.1 mouth of single-chip microcomputer links to each other with the base stage B2 of triode Q2 by resistance R 11, the P2.2 mouth of single-chip microcomputer links to each other with the base stage B3 of triode Q3 by resistance R 10, the P2.3 mouth of single-chip microcomputer links to each other with the base stage B4 of triode Q4 by resistance R 9, collector C1, the C2 of triode Q1, Q2, Q3, Q4, C3, C4 link to each other with the position choosing end pin 9,10,11,12 of digital indicator respectively, and the emitter E 1 of triode Q1, Q2, Q3, Q4, E2, E3, E4 connect power supply simultaneously.The pin 18,19 of single-chip microcomputer connects two pins of crystal oscillator H1 respectively, and passes through capacitor C 2, C3 ground connection respectively.The pin 31,40 of single-chip microcomputer connects power supply; Pin 20 ground connection.

Shown in Figure 3, be hyperacoustic radiating circuit, the 74ls04 chip that employing has inverter function constitutes, three input port pins 1 of the phase inverter of chip 74ls04, pin 3, pin 5 links to each other with the P0.0 mouth of single-chip microcomputer simultaneously, the square-wave signal of the 40KHZ frequency that the reception single-chip microcomputer sends, wherein the output terminal pin 2 of phase inverter pin 1 input port simultaneously and phase inverter input port pin 11, pin 13 links to each other, wherein the delivery outlet pin 10 of pin 11 links to each other with the positive pole of ultrasonic sensor, the delivery outlet pin 4 of pin 3 links to each other with the negative pole of ultrasonic sensor with the delivery outlet pin of pin 56 simultaneously, to constitute the required driving voltage of ultrasonic sensor.Pin 12 passes through resistance R 1 respectively with the negative pole of ultrasonic sensor simultaneously, and R2 is connected to power supply.

Shown in Figure 4, be the ultrasonic reception circuit, utilize ultrasonic receiving chip CX20106A and correspondent peripheral circuit to form the ultrasonic reception circuit and receive the ultrasound wave that reflects through rib, wherein pin of chip 1 is the ultrasonic signal input end, the input impedance of this pin is about 40k Ω, connect the positive pole of ultrasonic sensor, negative pole is by filter capacitor C1 ground connection.Being connected the RC series network between pin 2 and the ground, is an ingredient of negative feedback series network, and the numerical value that changes them can change the gain and the frequency characteristic of prime amplifier.Increase resistance R 1 or reduce capacitor C 2, amount of negative feedback will be increased, enlargement factor descends, otherwise then enlargement factor increases.Be connected detection capacitor C 3 between pin 3 and the ground, greatly mean value detection of electric capacity, moment, corresponding sensitivity was low; If capacity is little, then be peak detection, moment is corresponding highly sensitive.Pin 4 is an earth terminal.Insert a resistance R 2 between pin 5 and power supply, in order to the centre frequency f0 of bandpass filter to be set, resistance R 2 resistances are big more, and centre frequency is low more, during R=200k Ω, and f0 ≈ 42kHZ.Meet an integrating capacitor C4 between pin 6 and the ground, can suitably adjust detection range.Pin 7 is the guidance command output terminal, and it is the open collector way of output, and this pin connects a pull-up resistor R3 to power end, and this end is not output as high level when having acknowledge(ment) signal, then produces decline when signal is arranged, and can trigger the external interrupt of single-chip microcomputer.Pin 8 is a positive source, and voltage is 4.5~5.5V.

Shown in Figure 5, operational flow diagram for single-chip microcomputer, the steps include: to open the external interrupt of single-chip microcomputer and the enable bit that timer 0 interrupts, allow single-chip microcomputer generation external interrupt and timer 0 to interrupt, the working method of timer 0 and timer 1 is set, the initial value of timer 0 and timer 1 is set, start timer 0 and timer 1, produce the square wave that frequency is 40KHZ by the P0.0 mouth negate of single-chip microcomputer behind the 12.5us of timer 1 timing with this, drive ultrasonic sensor and send ultrasound wave, wait sees whether single-chip microcomputer external interrupt takes place, if, show that then the ultrasonic reflections signal receives successfully, after entering external interrupt, close and interrupt and timer 0, this moment, the count value of timer 0 was ultrasound wave travel-time in path back and forth, after recording distance, can calculate the velocity of propagation of ultrasound wave in this path, according to the ultrasound wave temperature-measurement principle, drawn hyperacoustic velocity of propagation and temperature has certain relation by utilizing, further to have drawn the measurement result of temperature, and show by digital indicator, withdraw from interruption after showing 10S, device will be measured again.If do not receive ultrasonic signal, then external interrupt does not take place in single-chip microcomputer, arrived the break period of timer 0, timer 0 interrupts, disconnected and the timer 0 in the Central Shanxi Plain of having no progeny in entering, and send digital indicator with E, show this measurement result mistake, and withdraw from interruption after showing 10S, device will be measured again.

Measuring ultrasonic wave coal wall temperature method of the present invention: fixed point is provided with the ultrasonic sensor that a frequency is about 40KHZ under coal mine; Open the interrupt control position of timer 0 of single chip circuit and the interrupt control position of external interrupt mouth, the interrupt control position of timeing closing device 1, the working method that the timer 0 of single-chip microcomputer is set is 16 counting modes, and initial value is made as 0, the timer 1 that single-chip microcomputer is set adopts 8 automatic refitting modes, the initial value of most-significant byte and least-significant byte all is made as 0xF4, and startup timer 0 and timer 1, timer 0 is used to write down hyperacoustic travel-time, the timing of single-chip microcomputer by the overflow position of timer 1 being judged timer 1 is to denying to come the P0.0 mouth of control single chip computer to send the square wave that frequency is 40KHZ, adopt the P0.0 mouth control ultrasonic transmission/reception sensor of single chip circuit to send the ultrasonic signal that is about 40KHZ with this, ultrasonic sensor receives the ultrasonic signal through the rib reflected back, utilize the chip CX20106A characteristic of ultrasound wave receiving circuit, when receiving signal, level on the pin 7 becomes low level by high level, the pin 7 of CX20106A is linked to each other with the external interrupt mouth of single chip circuit, the external interrupt mouth that can trigger single-chip microcomputer interrupts, after entering interruption of interruption pass and timer 0, the count value of timer 0 is the time delay t between ultrasonic emitting signal and reflected back signal at this moment;

Measure between fixed point ultrasonic sensor and the rib apart from l, obtain the signal velocity v of ultrasonic signal on this path by formula v=2l/t;

Determine coal seam ambient gas constant R and adiabatic exponent K, according to The Ideal-Gas Equation: pV=nRT, under the known standard situation, the volume of 1mol ideal gas is about 22.4L, wherein:

P=101325Pa, T=273.15K, n=1mol, V=22.4L is about 8314.2J/molk for entering to obtain R.Adiabatic exponent K is about 1.4, according to the molecular weight M of gas, utilizes acoustic thermometry principle formula:

C = ( K · R M · T ) 1 2 - - - ( 1 )

Draw the temperature computation formula thus:

T = C 2 · M K · R - - - ( 2 )

In the above-mentioned formula: the velocity of propagation (m/s) of C-ultrasound wave in medium; R-gas law constant (J/molk); The K-adiabatic exponent; The molecular weight of M-gas (kg/mol); T-measures temperature.

For particular environment, the molecular weight M and the adiabatic exponent K of gas law constant R and gas are approximately known constant, to record hyperacoustic velocity of propagation, carry out data processing by single-chip microcomputer, can calculate to be measured temperature, and this measurement result is shown by digital indicator 5.

Repeat above-mentioned steps, can carry out the measurement of next some position.

Claims (5)

1. measuring ultrasonic wave coal wall temperature method is characterized in that:
A. fixed point is provided with the ultrasonic sensor that a frequency is about 40KHZ under coal mine;
B. adopt single chip circuit control ultrasonic transmit circuit to drive ultrasonic sensor and send the ultrasonic signal that is about 40KHZ, utilize the function of ultrasonic transmit circuit phase inverter, ultrasonic transmit circuit is exported positive and negative 5 volts driving voltage, the work of driving ultrasonic sensor, this ultrasonic sensor receives the ultrasonic signal of reflected back simultaneously, external interrupt by ultrasound wave receiving circuit triggering single chip circuit draws the time delay t between signal;
C. measure between fixed point ultrasonic sensor and the rib apart from l, obtain the signal velocity v of ultrasonic signal on this path by formula v=2l/t;
D. determine coal seam gas law constant R and gas adiabatic exponent K on every side, carry out digital processing, demonstrate the temperature of the rib of surveying through digital indicator by single-chip microcomputer.
2. measuring ultrasonic wave coal wall temperature device, it is characterized in that: it is by ultrasonic sensor, single chip circuit, ultrasonic transmit circuit, ultrasound wave receiving circuit and digital indicator constitute, wherein: ultrasonic sensor is connected with the ultrasound wave receiving circuit with ultrasonic transmit circuit simultaneously, and the external interrupt mouth of single chip circuit is connected with the ultrasound wave receiving circuit, and the output interface of single chip circuit is connected with digital indicator.
3. according to right 2 described measuring ultrasonic wave coal wall temperature devices, it is characterized in that: the model of described ultrasonic sensor is TCF40-25TR1, and the model of single chip circuit is AT89S52, and the digital indicator model is SM410561K.
4. according to right 2 described measuring ultrasonic wave coal wall temperature devices, it is characterized in that: described ultrasonic transmit circuit adopts the 74ls04 chip, three input port pins 1 of the phase inverter of chip 74ls04, pin 3, pin 5 link to each other with the P0.0 mouth of single-chip microcomputer simultaneously, the output terminal pin 2 of phase inverter pin 1 input port links to each other with phase inverter input port pin 11, pin 13 simultaneously, the delivery outlet pin 10 of pin 11 links to each other with the positive pole of ultrasonic sensor, and the delivery outlet pin 4 of pin 3 links to each other with the negative pole of ultrasonic sensor with the delivery outlet pin of pin 56 simultaneously.
5. according to right 2 described measuring ultrasonic wave coal wall temperature devices, it is characterized in that: described ultrasound wave receiving circuit adopts ultrasonic receiving chip CX20106A, the pin 1 of chip CX20106A connects the positive pole of ultrasonic sensor, negative pole is by filter capacitor C1 ground connection, be connected the RC series network between pin 2 and the ground, be connected detection capacitor C 3 between pin 3 and the ground, pin 4 is an earth terminal, insert a resistance R 2 between pin 5 and power supply, meet an integrating capacitor C4 between pin 6 and the ground, pin 7 is the guidance command output terminal, and this pin connects a pull-up resistor R3 to power end, pin 8 is a positive source, and voltage is 4.5~5.5V.
CNA2008101945332A 2008-10-30 2008-10-30 Method and device for measuring ultrasonic wave coal wall temperature CN101408462A (en)

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101750157B (en) * 2010-01-12 2011-06-22 浙江大学 Temperature detection and signal transmission device under vacuum environment
CN102539009A (en) * 2012-01-06 2012-07-04 华北电力大学 System for monitoring fire facing side wall temperature of water cooled wall of power station boiler on line, and monitoring method
CN103149862A (en) * 2013-02-05 2013-06-12 中国矿业大学 Automatic sound emission monitoring method and automatic sound emission monitoring device
CN105241574A (en) * 2015-10-13 2016-01-13 华北电力大学(保定) Method for acoustically reconstructing three-dimensional temperature field by taking regard of sound ray bending behavior
CN105300553A (en) * 2015-09-08 2016-02-03 重庆大学 Travel time measurement method based on ultrasonic two-dimensional temperature measurement device
CN105486424A (en) * 2014-09-17 2016-04-13 南京理工大学 Ultrasonic non-invasive measurement method for transient temperature field of inner wall of combustion chamber
CN105698961A (en) * 2016-04-14 2016-06-22 重庆大学 Method for rebuilding of three-dimensional temperature field under microwave heating environment
CN108663969A (en) * 2018-05-15 2018-10-16 郑州云海信息技术有限公司 A kind of SCM Based power panel sequential time delay module and method
CN110933273A (en) * 2019-11-27 2020-03-27 重庆特斯联智慧科技股份有限公司 Face shooting device and system suitable for ground installation of building

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101750157B (en) * 2010-01-12 2011-06-22 浙江大学 Temperature detection and signal transmission device under vacuum environment
CN102539009A (en) * 2012-01-06 2012-07-04 华北电力大学 System for monitoring fire facing side wall temperature of water cooled wall of power station boiler on line, and monitoring method
CN103149862A (en) * 2013-02-05 2013-06-12 中国矿业大学 Automatic sound emission monitoring method and automatic sound emission monitoring device
CN105486424A (en) * 2014-09-17 2016-04-13 南京理工大学 Ultrasonic non-invasive measurement method for transient temperature field of inner wall of combustion chamber
CN105300553A (en) * 2015-09-08 2016-02-03 重庆大学 Travel time measurement method based on ultrasonic two-dimensional temperature measurement device
CN105241574A (en) * 2015-10-13 2016-01-13 华北电力大学(保定) Method for acoustically reconstructing three-dimensional temperature field by taking regard of sound ray bending behavior
CN105241574B (en) * 2015-10-13 2017-11-07 华北电力大学(保定) Consider three-dimensional temperature field acoustics method for reconstructing in the stove of Ray-tracing method behavior
CN105698961A (en) * 2016-04-14 2016-06-22 重庆大学 Method for rebuilding of three-dimensional temperature field under microwave heating environment
CN108663969A (en) * 2018-05-15 2018-10-16 郑州云海信息技术有限公司 A kind of SCM Based power panel sequential time delay module and method
CN110933273A (en) * 2019-11-27 2020-03-27 重庆特斯联智慧科技股份有限公司 Face shooting device and system suitable for ground installation of building

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