Ion type flame speed measuring device with telescopic pole needle and speed measuring method thereof

文档序号:1887673 发布日期:2021-11-26 浏览:17次 中文

阅读说明:本技术 一种极针可伸缩的离子式火焰测速装置及其测速方法 (Ion type flame speed measuring device with telescopic pole needle and speed measuring method thereof ) 是由 李贝贝 郑金磊 赵江坤 刘秀梅 李伟 刘利利 舒远 刘威威 魏令行 于 2021-07-21 设计创作,主要内容包括:本发明公开了一种极针可伸缩的离子式火焰测速装置及其测速方法,包括数据处理器、高速通讯模块、离子式火焰传感器、实验管道,能够实现传感器极针长度的改变,进而实现一个传感器对不同直径的管道的火焰传播信号的测量,通过设计的数据采集电路,通过改变采集电路中电阻值的大小可以改变传感器的量程,提高数据采集装置的通用性,通过金属瓦片使采集电路与极针相连,能够提高采集电路的灵敏度,所述传感器前端采用螺纹连接,便于传感器的安装,通过多个离子式火焰传感器组合测试,采用求导、双位置多传感器协同方式计算火焰锋面到达时刻,火焰速度计算精度更高。(The invention discloses an ion type flame speed measuring device with a telescopic pole needle and a speed measuring method thereof, which comprise a data processor, a high-speed communication module, an ion type flame sensor and an experimental pipeline, can realize the change of the length of the pole needle of the sensor, further realizes the measurement of flame propagation signals of pipelines with different diameters by one sensor, and through the designed data acquisition circuit, the measuring range of the sensor can be changed by changing the resistance value in the acquisition circuit, the universality of the data acquisition device is improved, the collection circuit is connected with the polar needle through the metal tile, the sensitivity of the collection circuit can be improved, the front end of the sensor adopts threaded connection, the installation of the sensor is convenient, through the combination test of a plurality of ionic flame sensors, adopt and turn round, two position multisensor collaborative mode calculate the flame frontal arrival moment, flame speed calculation accuracy is higher.)

1. An ion type flame speed measuring device with a telescopic pole needle comprises an experiment pipeline (5) with two ends connected with a pipeline (6) to be measured, wherein a plurality of pressure measuring holes are respectively and uniformly distributed on two sections of the experiment pipeline (5) in an annular direction, short guide pipes are arranged on the pressure measuring holes, an ion type flame sensor (4) is installed on each short guide pipe, the ion type flame sensor (4) comprises a sensor shell, a threaded probe in threaded connection with each short guide pipe is arranged on the sensor shell, a ceramic tube (46) is arranged in each threaded probe, and one end, far away from the threaded probe, of each ceramic tube (46) is connected with a damping ring (47); the method is characterized in that:

a sleeve (410) is fixed in the sensor shell, a movable fastening ring (416) is arranged in the sleeve (410), a polar needle fixing tube (418) which can move and is used for fixing the polar needle (415) is arranged in the fastening ring (416), the pole needle (415) sequentially passes through the damping ring (47) and the ceramic tube (46) and then extends out of the sensor shell, the polar needle fixing tube (418) is provided with a first clamping head (4181) and a second clamping head (4182) which can extrude the polar needle (415) to move, the fastening ring (416) corresponds to the first chuck (4181) and the second chuck (4182) and is used for controlling the first chuck (4181) and the second chuck (4182) to extrude the pole needle (415), a driven part (419) for driving the polar needle fixing tube (418) to move is arranged at the rear end of the polar needle fixing tube (418), a return spring (417) sleeved outside the polar needle fixing tube (418) is connected between the driven part (419) and the sleeve (410).

2. An ionic flame velocimetry device as claimed in claim 1, wherein said probe is retractable: the sensor housing comprises a housing front portion (41), a housing middle portion (42) and a housing rear portion (43), the ceramic tube (46) and the thread probe are fixed at the front end of the housing front portion (41), one end of the ceramic tube (46) is flush with the end portion of the thread probe of the housing front portion (41), the ceramic tube (46) is fixed with the thread probe in a sticking mode, and the damping ring (47) is fixed with the ceramic tube (46) in a sticking mode.

3. An ionic flame velocimetry device as claimed in claim 2, wherein said probe is retractable: the middle part (42) of the shell is in threaded connection with the front part (41) of the shell, one end of a compression spring (413) is fixedly welded at the rear end of the middle part (42) of the shell, and a metal tile (412) which is used for being tightly attached to the pole needle (415) is fixedly welded at the other end of the compression spring (413); casing rear portion (43) are pasted and are fixed with circuit board support (431), it is fixed with circuit board (48) to press from both sides tight on circuit board support (431), casing rear portion (43) are fixed with casing middle part (42) joint, casing rear portion (43) threaded connection has protective sheath (49), and the rear end of utmost point needle (415) penetrates in protective sheath (49).

4. An ionic flame velocimetry device as claimed in claim 3, wherein said probe is retractable: the circuit board support (431) is provided with a movable clamping plate (4313), a fixed clamping plate (4314) corresponding to the movable clamping plate (4313) and a trapezoidal groove (4311), and the trapezoidal groove (4311) is internally provided with a tension spring (4312) which is welded and fixed with the fixed clamping plate (4314) and the movable clamping plate (4313).

5. An ionic flame velocimetry device as claimed in claim 3, wherein said probe is retractable: the terminal (482) of the ion probe of the circuit board (48) is connected to the ear ring (4121) of the metal tile (412) through a lead (414), the power terminal (481) and the data acquisition terminal (483) of the circuit board (48) are connected to an aviation plug (44) on the rear part (43) of the shell through signal wires (45), and the power terminal (481), the terminal (482) of the ion probe and the data acquisition terminal (483) are connected with a slide rheostat (484).

6. An ionic flame velocimetry device as claimed in claim 3, wherein said probe is retractable: and a felt ring (421) corresponding to the polar needle (415) is arranged on the rear part (43) of the shell.

7. An ionic flame velocimetry device as claimed in claim 1, wherein said probe is retractable: the first clamp head (4181) and the second clamp head (4182) are oppositely arranged to form an inverted circular truncated cone-shaped clamp head, the fastening ring (416) forms an inverted circular truncated cone-shaped cylinder structure corresponding to the inverted circular truncated cone-shaped clamp head, a blocking edge (4101) corresponding to the sleeve (410) is formed at the upper edge of the fastening ring (416), a step edge (411) corresponding to the blocking edge (4101) is formed in the sensor shell, and two holes for the pole needle (415) to penetrate through and clamp the pole needle are formed in the pole needle fixing tube (418).

8. An ionic flame velocimetry device as claimed in claim 1, wherein said probe is retractable: the distance between the two sections of the experimental pipeline (5) is 3-5 times of the inner diameter of the experimental pipeline (5).

9. An ionic flame velocimetry device as claimed in claim 1, wherein said probe is retractable: the diameter of the short conduit does not exceed 1/3 of the diameter of the experimental pipe (5).

10. A method for measuring flame speed by using the ionic flame speed measuring device with telescopic pole needles as claimed in any one of claims 1 to 9, wherein: the method comprises the following steps:

s1, before the test starts, checking the installation and connection of each component of the test system, and after the check is finished, entering the step S2;

s2, starting the data processor 1 before the flame in the experimental pipeline is ignited or before the flame is propagated to the position of the sensor;

s3, respectively reading signal change curves of four flame sensors on two sections of a pipeline when the flame combustion in the experimental pipeline is finished; the data processor calculates a first derivative of a flame signal change curve, and the time corresponding to the maximum value of the curve is the time when the flame front reaches the position of the flame sensor;

s4, recording the arrival time of the flame front obtained by the four flame sensors on the same section, calculating to obtain an average time value, namely the arrival time t1 of the flame recorded by the flame sensors on the section, and solving to obtain the arrival time t2 of the flame recorded by the other front;

s5, the axial distance between the two sections is L, and the flame propagation speed calculation formula is as follows:

Technical Field

The invention belongs to the field of flame sensors, and particularly relates to an ion type flame speed measuring device with a telescopic pole needle and a speed measuring method thereof.

Background

In the process of transporting combustible substances such as petroleum dust, the danger of explosion is often accompanied. When the piping for transporting the material is mixed with the spark, there is a risk of explosion occurring in the transportation piping. When an explosion accident occurs, the accident can not only cause the casualties of people, but also cause huge economic loss. At present, the main solution to this problem is to arrange a spark detection and extinguishing device in the conveying pipeline, and to find the dangerous sparks in the pipeline and extinguish them in time by the spark detection and extinguishing device. The flame sensor is an important component of the spark detection device, and whether the flame sensor can accurately detect sparks determines whether the detection system can normally operate. The existing flame sensors mainly comprise an infrared flame sensor, an ultraviolet flame sensor and an ion probe type flame sensor.

The infrared and ultraviolet flame sensors detect the presence of a spark by capturing the infrared/ultraviolet spectrum emitted by the spark. However, due to the influence of the detection principle of the infrared flame sensor and the ultraviolet flame sensor, the infrared flame sensor and the ultraviolet flame sensor are easily interfered by other light sources to cause misjudgment. Thus, infrared and ultraviolet flame sensors are generally suitable for spark detection in enclosed environments.

The working principle of the ion probe type flame sensor is as follows: the combustion reaction has ion reaction, so that the flame has positive and negative ions, when an electric field is applied to the flame, the external circuit can generate weak current, and whether the flame passes through can be judged by detecting whether the current in the external circuit exists. Compared with infrared type and ultraviolet type flame sensors, the ion probe type flame sensor has no misjudgment condition and is accurate in detection. However, the pole needles with different lengths are needed for pipelines with different diameters, the length of the pole needle of the ion probe type flame sensor is fixed, and the same sensor cannot detect flame signals of the pipelines with different diameters.

Disclosure of Invention

In view of the technical defects, the invention aims to provide an ion type flame speed measuring device with a telescopic pole needle.

In order to solve the technical problems, the invention adopts the following technical scheme:

the invention provides an ion type flame speed measuring device with telescopic pole needles, which comprises an experimental pipeline, wherein two ends of the experimental pipeline are connected with a pipeline to be measured, a plurality of pressure measuring holes are respectively and uniformly distributed on two sections of the experimental pipeline in an annular manner, short guide pipes are arranged on the pressure measuring holes, ion type flame sensors are arranged on the short guide pipes, each ion type flame sensor comprises a sensor shell, a threaded probe in threaded connection with the short guide pipe is arranged on the sensor shell, a ceramic pipe is arranged in the threaded probe, and one end, far away from the threaded probe, of the ceramic pipe is connected with a damping ring;

a sleeve is fixed in the sensor shell, a movable fastening ring is arranged in the sleeve, a movable polar needle fixing tube used for fixing a polar needle is arranged in the fastening ring, the polar needle sequentially penetrates through the damping ring and the ceramic tube and then extends out of the sensor shell, a first chuck and a second chuck which can extrude the polar needle to move are arranged on the polar needle fixing tube, the fastening ring corresponds to the first chuck and the second chuck and is used for controlling the extrusion of the first chuck and the second chuck on the polar needle, a driven part used for driving the polar needle fixing tube to move is arranged at the rear end of the polar needle fixing tube, and a return spring sleeved outside the polar needle fixing tube is connected between the driven part and the sleeve; the ion type flame sensor is in communication connection with the high-speed communication module, the high-speed communication module is in communication connection with the data processor, and the sensor shell is provided with a driving button corresponding to a driven part.

Preferably, the sensor housing includes that the casing is anterior, casing middle part, casing rear portion, ceramic pipe, screw probe are fixed at the anterior front end of casing, the tip parallel and level of the screw probe of ceramic pipe one end and casing front portion, the ceramic pipe is pasted fixedly with the screw probe, the damping circle is pasted fixedly with the ceramic pipe.

Preferably, the middle part of the shell is in threaded connection with the front part of the shell, one end of a compression spring is fixedly welded at the rear end of the middle part of the shell, and a metal tile tightly attached to the pole needle is fixedly welded at the other end of the compression spring; the utility model discloses a quick-witted pole needle, including casing, casing rear portion, circuit board support, casing rear portion and casing middle part joint, casing rear portion threaded connection has the protective sheath, and the rear end of pole needle penetrates in the protective sheath.

Preferably, the circuit board support is provided with a movable clamping plate, a fixed clamping plate corresponding to the movable clamping plate and a trapezoidal groove, and a tension spring welded and fixed with the fixed clamping plate and the movable clamping plate is arranged in the trapezoidal groove.

Preferably, the terminal of the ion probe of the circuit board is connected to the earring of the metal tile through a lead, the power supply terminal and the data acquisition terminal of the circuit board are connected to the aviation plug on the rear part of the shell through signal wires, and the power supply terminal, the terminal of the ion probe and the data acquisition terminal are connected with a slide rheostat.

Preferably, a felt ring corresponding to the polar needle is arranged on the rear part of the shell.

Preferably, chuck one, chuck two set up relatively and form an inverted circular truncated cone type chuck, the tighrening ring forms an inverted circular truncated cone shape tube structure that corresponds with inverted circular truncated cone type chuck, the tighrening ring top edge is formed with the edge that blocks that corresponds with the sleeve, be formed with in the sensor casing and block along the ladder edge that corresponds, it has two confession utmost point needles to penetrate and plays the hole of clamping action to it to open on the utmost point needle fixed tube.

Preferably, the distance between two sections of the test tube is in the range of 3-5 times the inner diameter of the test tube.

Preferably, the diameter of the short conduit does not exceed 1/3 the diameter of the experimental pipe.

The invention also provides a speed measurement method of flame propagation speed by using the device, which comprises the following steps:

s1, before the test starts, checking the installation and connection of each component of the test system, and after the check is finished, entering the step S2;

s2, starting the data processor 1 before the flame in the experimental pipeline is ignited or before the flame is propagated to the position of the sensor;

s3, respectively reading signal change curves of four flame sensors on two sections of a pipeline when the flame combustion in the experimental pipeline is finished; the data processor calculates a first derivative of a flame signal change curve, and the time corresponding to the maximum value of the curve is the time when the flame front reaches the position of the flame sensor;

s4, recording the arrival time of the flame front obtained by the four flame sensors on the same section, calculating to obtain an average time value, namely the arrival time t1 of the flame recorded by the flame sensors on the section, and solving to obtain the arrival time t2 of the flame recorded by the other front;

s5, the axial distance between the two sections is L, and the flame propagation speed calculation formula is as follows:

advantageous effects

1. The invention can realize the change of the length of the pole needle of the sensor, thereby realizing the measurement of flame propagation signals of pipelines with different diameters by one sensor;

2. according to the designed data acquisition circuit, the measuring range of the sensor can be changed by changing the resistance value in the acquisition circuit, so that the universality of the data acquisition device is improved;

3. the collection circuit is connected with the polar needle through the metal tile, so that the sensitivity of the collection circuit can be improved;

4. the front end of the sensor is in threaded connection, so that the sensor is convenient to mount;

5. through the combination test of a plurality of ionic flame sensors, adopt and turn round, two position multisensor collaborative mode calculate the flame frontal arrival moment, flame speed calculation accuracy is higher.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a diagram of a flame propagation speed testing apparatus;

FIG. 2 is a front view of the flame sensor;

FIG. 3 is a side view of a flame sensor;

FIG. 4 is a sectional view of section A-A in front elevation;

FIG. 5 is a sectional view of section B-B in front elevation;

FIG. 6 is an isometric view of a metal tile;

FIG. 7 is an isometric view of the actuator button;

FIG. 8 is a three-view diagram of a circuit board support;

FIG. 9 is a circuit diagram of an ion current data acquisition circuit;

the names of the components in the figure are:

1-data processor, 2-high speed processing module, 3-signal shielding wire, 4-ion type flame sensor, 5-experimental pipe, 6-measured pipe, 41-housing front, 42-housing middle, 43-housing rear, 431-bracket, 44-aviation plug, 45-signal wire, 46-ceramic tube, 47-damping ring, 48-circuit board, 49-protective sheath, 410-sleeve, 4101-blocking edge, 411-step edge, 412-metal tile, 4121-ear ring, 413-pressure spring, 414-lead wire, 415-pole needle, 416-fastening ring, 417-return spring, 418-pole needle fixing tube, 4181-clamp head one, 4182-clamp head two, 419-driven mechanism, 420-drive button, 421-felt ring, 4311-trapezoidal groove, 4312-tension spring, 4313-movable clamp plate, 4314-fixed clamp plate, 481-power terminal, 482-ion probe terminal, 481-ion probe terminal, 483- -data acquisition terminal, 484- -slide rheostat.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1: as shown in fig. 1-9, the present invention provides an ion type flame speed measuring device with a telescopic pole needle, which comprises a data processor 1, a high speed communication module 2, an ion type flame sensor 4, an experimental pipe 5, the two ends of the experimental pipeline 5 are connected with a pipeline 6 to be tested, a plurality of pressure measuring holes vertical to the pipe wall are respectively and uniformly arranged on the circumference of two sections vertical to the axis of the experimental pipeline 5, each pressure measuring hole is correspondingly provided with 1 short guide pipe vertical to the axis of the pipeline, each short guide pipe is provided with an ion type flame sensor 4, the ion type flame sensor 4 is in communication connection with the high-speed communication module 2, the high-speed communication module 2 is in communication connection with the data processor 1, the ion type flame sensor 4 is connected to a welding short guide pipe uniformly distributed on the test pipeline 5 by using threads;

the acquisition element of the ion type flame sensor is flush with the inner wall of the test pipeline 5, the aviation plug 44 of the ion type flame sensor is connected with the signal acquisition inlet of the high-speed communication module 2 by using a shielding signal wire 3, and the high-speed communication module 2 is connected with the data processor 1 by using a network cable; the ion type flame sensor 4 comprises a sensor shell, wherein a threaded probe in threaded connection with a short guide pipe is arranged on the sensor shell, a ceramic tube 46 is arranged in the threaded probe, one end, far away from the threaded probe, of the ceramic tube 46 is connected with a damping ring 47, a sleeve 410 is fixedly arranged in the sensor shell, a movable fastening ring 416 is arranged in the sleeve 410, a movable polar needle fixing tube 418 is correspondingly arranged in the fastening ring 416, a polar needle 415 is fixed at the end part of the polar needle fixing tube 418, and the polar needle 415 sequentially penetrates through the damping ring 47 and the ceramic tube 46 and extends out of the sensor shell;

the pole needle fixing tube 418 is provided with a first chuck 4181 and a second chuck 4182 which can press the pole needle 415 to move, the fastening ring 416, the first chuck 4181 and the second chuck 4182 are correspondingly used for controlling the first chuck 4181 and the second chuck 4182 to press the pole needle 415, and the rear end of the pole needle fixing tube 418 is provided with a driven part 419 which can drive the pole needle fixing tube 418 to move

The sensor housing is provided with an actuating button 420 corresponding to an actuated member 419, and a return spring 417 fitted around the outside of the needle fixing tube 418 is connected between the actuated member 419 and the sleeve 410. The sensor casing includes casing front portion 41, casing middle part 42, casing rear portion 43, ceramic pipe 46, screw probe are fixed at casing front portion 41 front end, and the tip parallel and level of the screw probe of ceramic pipe 46 one end and casing front portion 41, ceramic pipe 46 is pasted fixedly with the screw probe, damping circle 47 is pasted fixedly with ceramic pipe 46.

The middle part 42 of the shell is in threaded connection with the front part 41 of the shell, one end of a compression spring 413 is fixedly welded at the rear end of the middle part 42 of the shell, and a metal tile 412 which is tightly attached to the pole pin 415 is fixedly welded at the other end of the compression spring 413; casing rear portion 43 is pasted and is fixed with circuit board support 431, the tight circuit board 48 that is fixed with of clamp on the circuit board support 431, casing rear portion 43 is fixed with casing middle part 42 joint, casing rear portion 43 threaded connection has protective sheath 49, and the rear end of utmost point needle 415 penetrates in the protective sheath 49. The circuit board support 431 is provided with a movable clamping plate 4313, a fixed clamping plate 4314 corresponding to the movable clamping plate 4313 and a trapezoidal groove 4311, and the trapezoidal groove 4311 is internally provided with a tension spring 4312 which is fixedly welded with the fixed clamping plate 4314 and the movable clamping plate 4313.

The terminal 482 of the ion probe of the circuit board 48 is connected to the ear ring 4121 of the metal tile 412 through the lead 414, the power terminal 481 and the data acquisition terminal 483 of the circuit board 48 are connected to the aviation plug 44 on the rear 43 of the housing through the signal wire 45, and the power terminal 481, the terminal 482 of the ion probe and the data acquisition terminal 483 are connected to the slide rheostat 484. The rear portion 43 of the housing is provided with a felt ring 421 corresponding to the pole needle 415.

The first chuck 4181 and the second chuck 4182 are oppositely arranged to form an inverted circular truncated cone-shaped chuck, the fastening ring 416 forms an inverted circular truncated cone-shaped structure corresponding to the inverted circular truncated cone-shaped chuck, the blocking edge 4101 corresponding to the sleeve 410 is formed at the upper edge of the fastening ring 416, the step edge 411 corresponding to the blocking edge 4101 is formed in the sensor housing, and two holes for the pole needle 415 to penetrate through and clamp are formed in the pole needle fixing tube 418.

The axial distance between the two sections perpendicular to the axis is in the range of 3-5 times the inner diameter of the experimental pipe 5. The diameter of short pipe is no longer than 1/3 of experiment pipeline 5 diameter, and the pipe is kept away from pipeline end hole and is the screw hole, experiment pipeline 5 passes through the ring flange with by survey pipeline 6 and is connected.

When in specific use: in operation, when the pole pin 415 needs to be extended, the driving button 420 is pressed down and pushed by the driving mechanism 419 to push the pole pin fixing tube 418 to move forward together, so that the fastening ring 416 is attached to and moves forward together with the chuck 4181 and the chuck 4182, and the pole pin 415 is pressed by the chuck 4181 and the chuck 4182 to move forward together under the action of the pressing force. When the fastening ring 416 is stopped by the step 411 after moving forward a certain distance, the needle fixing tube 418 will continue to move forward a certain distance, during the moving process, the fastening ring 416 is separated from the chuck 4181 and the chuck 4182, the needle 415 is no longer pressed by the chuck 4181 and the chuck 4182 and is stopped by the friction force, which is mainly provided by the damping ring 47, and the needle 415 extends a certain length from the damping ring.

When the actuator button 420 is released, the needle holding tube 418 moves backward by the return spring 417, and when the actuator button moves a certain distance, the fastening ring 416 is blocked by the blocking edge 4101 to stop moving backward, the needle holding tube 418 continues to move backward, the fastening ring 416 is engaged with the collet 4181 and the collet 4182 again, the collet 4181 and the collet 4182 again clamp and hold the needle 415, and the actuator button 420 is pressed by the actuator 419 to return to its original position.

When the pole needle needs to be shortened, the working principle is similar to that when the pole needle is extended, and the details are not repeated. However, the difference is that the pole needle needs to be shortened to a certain length by external force in the process of shortening the pole needle, and the pole needle cannot be shortened by the sensor.

The invention also provides a speed measurement method of flame propagation speed by using the device, which comprises the following steps:

s1, before the test starts, checking the installation and connection of each component of the test system, and after the check is finished, entering the step S2;

s2, starting the data processor 1 before the flame in the experimental pipeline is ignited or before the flame is propagated to the position of the sensor;

s3, respectively reading signal change curves of four flame sensors on two sections of a pipeline when the flame combustion in the experimental pipeline is finished; the data processor calculates a first derivative of a flame signal change curve, and the time corresponding to the maximum value of the curve is the time when the flame front reaches the position of the flame sensor;

s4, recording the arrival time of the flame front obtained by the four flame sensors on the same section, calculating to obtain an average time value, namely the arrival time t1 of the flame recorded by the flame sensors on the section, and solving to obtain the arrival time t2 of the flame recorded by the other front;

s5, the axial distance between the two sections is L, and the flame propagation speed calculation formula is as follows:

it will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

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