Molecular velocity measurement system, molecular velocity measurement method, device and storage medium

Abstract

The embodiment of the present application provides a molecular velocity measurement system, a molecular velocity measurement method, an apparatus and a storage medium, which belong to the field of material measurement technology. The system includes: a gas pulse valve ejects a target molecule according to a first delay trigger signal; a laser excitation module sets a first laser signal according to the energy transition information of the target molecule to excite the target molecule to obtain an excited molecule; a laser detection module sets a second laser signal according to the charge separation information of the target molecule, and ionizes the excited molecule according to the second laser signal to obtain a target ion; a delay signal generator sends a first delay trigger signal to the gas pulse valve, and records the first laser time and the second laser time; a data processing module obtains the target velocity according to the first laser time, the second laser time and the preset flight distance. The embodiment of the present application can effectively improve the measurement accuracy of molecular velocity over long distances by adopting molecular velocity measurement using laser ionization detection.

Description

Technical Field

[0001] The present application relates to the field of material measurement technology, and in particular to a molecular velocity measurement system, a molecular velocity measurement method, a device, and a storage medium. Background Art

[0002] At present, Molecular Tagging Velocimetry (MTV) is an optical measurement technology that uses laser technology to directly measure the velocity of specific molecules in a flow field. It has the characteristics of no external interference, non-contact measurement, high temporal and spatial resolution and accuracy. Related technologies usually use MTV combined with a charge coupled device (CCD), that is, by fluorescently labeling the molecules and determining the molecular velocity by measuring the trajectory and pattern of the fluorescence. However, since the fluorescence emitted by a molecule is weak, and the fluorescent label of the molecule will continue to decay as the flight distance increases, it will cause significant velocity measurement errors. Therefore, the molecular velocity measurement technology used in related technologies is not accurate enough for long-distance molecular velocity measurements. Summary of the Invention

[0003] The main purpose of the embodiments of the present application is to propose a molecular velocity measurement system, a molecular velocity measurement method, an apparatus and a storage medium, which can effectively improve the measurement accuracy of molecular velocity over long distances by adopting molecular velocity measurement using laser ionization detection.

[0004] To achieve the above-mentioned purpose, the first aspect of the embodiment of the present application proposes a molecular velocity measurement system, which includes: a delay signal generator, a gas pulse valve, a laser excitation module, a laser detection module and a data processing module, wherein the delay signal generator is respectively connected to the gas pulse valve, the laser excitation module, the laser detection module and the data processing module in communication; wherein,

[0005] The gas pulse valve is used to eject the target molecules according to the received first delayed trigger signal;

[0006] The laser excitation module is used to set a first laser signal according to the energy transition information of the target molecule, and excite the target molecule according to the laser of the first laser signal to obtain an excited molecule;

[0007] The laser detection module is used to set a second laser signal according to the charge separation information of the target molecule, and ionize the excited molecule according to the laser of the second laser signal to obtain target ions;

[0008] The delay signal generator is used to send the first delay trigger signal to the gas pulse valve, and is also used to record the first laser time when the laser excitation module marks the excited molecules, and record the second laser time when the laser detection module detects the target ions;

[0009] The data processing module is used to calculate the speed according to the first laser time, the second laser time and the preset flight distance to obtain the target speed of the target molecule.

[0010] In some embodiments, the laser detection module includes a laser detection unit and an ionization collector, and the laser detection module is used to set a second laser signal according to the charge separation information of the target molecule, and ionize the excited molecule according to the laser of the second laser signal to obtain the target ion, specifically including:

[0011] The laser detection unit sets a second laser signal according to the charge separation information of the target molecule;

[0012] The laser detection unit ionizes the excited molecules according to the laser of the second laser signal to obtain the target ions;

[0013] When the ionization collector identifies the target ion, the second laser time of obtaining the target ion is recorded by the delay signal generator.

[0014] In some embodiments, the laser detection unit includes an electrode plate and a laser detector, and the laser detection unit ionizes the excited molecules according to the laser of the second laser signal to obtain the target ions, including:

[0015] When the excited molecules fly to the preset excitation position of the electrode plate, the laser detector performs charge separation on the excited molecules according to the laser of the second laser signal to obtain the target ions and extranuclear electrons;

[0016] The target ions and extranuclear electrons are deflected according to the electrode plates, and the target ions are sent to the ionization collector.

[0017] In some embodiments, the laser excitation module is configured to set a first laser signal according to the energy transition information of the target molecule, and excite the target molecule according to the first laser signal to obtain an excited molecule, specifically comprising:

[0018] Setting a first laser signal according to energy transition information of the target molecule;

[0019] receiving a second delay trigger signal sent by the delay signal generator, and starting the laser excitation module according to the second delay trigger signal;

[0020] The target molecules in the ground state are excited according to the first laser signal to obtain the excited molecules in the excited state.

[0021] In some embodiments, before the laser detection unit sets the second laser signal according to the charge separation information of the target molecule, the laser detection module is used to set the second laser signal according to the charge separation information of the target molecule, and ionize the excited molecule according to the laser of the second laser signal to obtain the target ion, which specifically further includes:

[0022] Receive the third delay trigger signal sent by the delay signal generator, and start the laser detection module according to the third delay trigger signal.

[0023] In some embodiments, the gas pulse valve is configured to eject the target molecule according to the received first delayed trigger signal, including:

[0024] receiving the first delay trigger signal sent by the delay signal generator, and starting the gas pulse valve according to the first delay trigger signal;

[0025] The gas pulse valve ejects a gas mass with a broadened velocity, and the gas mass includes target molecules.

[0026] To achieve the above-mentioned purpose, a second aspect of an embodiment of the present application proposes a molecular velocity measurement method, which is applied to the molecular velocity measurement method proposed in the first aspect above. The method includes:

[0027] Start the laser excitation module according to a second delayed trigger signal sent to the laser excitation module by a delayed signal generator;

[0028] Setting a first laser signal of the laser excitation module according to the energy transition information of the target molecule;

[0029] The target molecules ejected from the gas pulse valve are excited at a preset excitation position by the laser of the first laser signal to obtain a first laser time;

[0030] Starting the laser detection module according to a third delayed trigger signal sent to the laser detection module by the delayed signal generator;

[0031] Setting a second laser signal of the laser detection module according to the charge separation information of the target molecule;

[0032] a second laser time obtained by ionizing the excited molecules at a preset detection position according to the second laser signal;

[0033] Speed ​​calculation is performed according to the first laser time, the second laser time and the preset flight distance to obtain a target speed of the target molecule.

[0034] In some embodiments, the preset flight distance is used to represent the mapping distance between the laser excitation module and the laser detection module in the flight direction of the target molecule, and the speed calculation is performed according to the first laser time, the second laser time and the preset flight distance to obtain the target speed of the target molecule, including:

[0035] determining a laser time difference according to the first laser time and the second laser time;

[0036] The speed is calculated based on the laser time difference and the preset flight distance to obtain the target speed.

[0037] To achieve the above-mentioned objectives, a third aspect of the embodiments of the present application provides a computer device, including:

[0038] at least one memory;

[0039] at least one processor;

[0040] at least one computer program;

[0041] The at least one computer program is stored in the at least one memory, and the at least one processor executes the at least one computer program to implement the multi-threaded memory management method described in the first aspect above.

[0042] To achieve the above-mentioned purpose, the fourth aspect of the embodiments of the present application proposes a computer-readable storage medium, which stores a computer program, and the computer program is used to enable a computer to execute the multi-threaded memory management method described in the first aspect above.

[0043] The embodiment of the present application proposes a molecular velocity measurement system, a molecular velocity measurement method, an apparatus and a storage medium. First, a target molecule is ejected through a gas pulse valve according to a received first delayed trigger signal. The laser excitation module sets a first laser signal according to the energy transition information of the target molecule, and excites the target molecule according to the laser of the first laser signal to obtain an excited molecule. Then, the laser detection module sets a second laser signal according to the charge separation information of the target molecule, and ionizes the excited molecule according to the laser of the second laser signal to obtain a target ion. Among them, the delayed signal generator is used to send a first delayed trigger signal to the gas pulse valve, and is also used to record the first laser time when the laser excitation module marks the excited molecule, and record the second laser time when the laser detection module detects the target ion. Finally, the data processing module calculates the speed according to the first laser time, the second laser time and the preset flight distance to obtain the target speed of the target molecule. The embodiment of the present application can effectively improve the measurement accuracy of molecular speed over long distances by adopting molecular velocity measurement using laser ionization detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is an optional structural diagram of the molecular velocity measurement system provided in an embodiment of the present application;

[0045] Figure 2 This is an optional flow chart of the gas pulse valve provided in the embodiment of the present application;

[0046] Figure 3 This is a velocity width distribution diagram of a gas mass ejected from a gas pulse valve provided in an embodiment of the present application;

[0047] Figure 4 This is an optional flow chart of the laser excitation module provided in an embodiment of the present application;

[0048] Figure 5 This is an optional flow chart of the laser detection module provided in an embodiment of the present application;

[0049] Figure 6 This is an optional flow chart of the molecular velocity measurement method provided in an embodiment of the present application;

[0050] Figure 7 yes Figure 6 Flowchart of step S670 in FIG.

[0051] Figure 8 This is a schematic diagram of the hardware structure of the computer device provided in the embodiment of the present application. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0053] It should be noted that although the device schematics illustrate functional module divisions and the flowcharts illustrate logical sequences, in certain circumstances, the steps shown or described may be performed in a sequence that differs from the module divisions in the device or the sequence in the flowcharts. The terms "first," "second," and so on, in the specification, claims, and drawings, are used to distinguish similar items and are not necessarily used to describe a specific sequence or precedence.

[0054] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application pertains. The terms used herein are for the purpose of describing the embodiments of this application only and are not intended to limit this application.

[0055] First, let’s analyze some of the terms used in this application:

[0056] A molecule is a whole composed of atoms bonded together in a specific bonding sequence and spatial arrangement. This bonding sequence and spatial arrangement is called the molecular structure. Atoms are the smallest units of matter, such as hydrogen and oxygen atoms. Atoms are composed of a nucleus and electrons.

[0057] Ground state: refers to the state in which the molecule is at the lowest energy level under normal conditions, and the electrons move in the orbit closest to the nucleus.

[0058] Excited state: refers to the state in which an atom or molecule is excited to a higher energy level but has not yet been ionized after absorbing a certain amount of energy.

[0059] At present, Molecular Tagging Velocimetry (MTV) is an optical measurement technology that uses laser technology to directly measure the velocity of specific molecules in a flow field. It has the characteristics of no external interference, non-contact measurement, high temporal and spatial resolution and accuracy. Related technologies usually use MTV combined with a charge coupled device (CCD), that is, by fluorescently labeling the molecules and determining the molecular velocity by measuring the trajectory and pattern of the fluorescence. However, since the fluorescence emitted by a molecule is weak, and the fluorescent label of the molecule will continue to decay as the flight distance increases, it will cause significant velocity measurement errors. Therefore, the molecular velocity measurement technology used in related technologies is not accurate enough for long-distance molecular velocity measurements.

[0060] Based on this, the embodiments of the present application provide a molecular velocity measurement system, a molecular velocity measurement method, an apparatus and a storage medium, which can effectively improve the measurement accuracy of molecular velocity over long distances by adopting molecular velocity measurement using laser ionization detection.

[0061] See also Figure 1 , Figure 1 This is an optional structural diagram of the molecular velocity measurement system provided in an embodiment of the present application. Figure 1 The molecular velocity measurement system can specifically include a delay signal generator 110, a gas pulse valve 120, a laser excitation module 130, a laser detection module 140 and a data processing module 150, and the delay signal generator 110 is respectively communicated with the gas pulse valve 120, the laser excitation module 130, the laser detection module 140 and the data processing module 150.

[0062] The gas pulse valve 120 is used to eject the target molecule 160 according to the received first delayed trigger signal;

[0063] The laser excitation module 130 is used to set a first laser signal according to the energy transition information of the target molecule 160, and excite the target molecule 160 according to the laser of the first laser signal to obtain an excited molecule 170;

[0064] The laser detection module 140 is used to set a second laser signal according to the charge separation information of the target molecule 160, and ionize the excited molecule 170 according to the laser of the second laser signal to obtain the target ion 180;

[0065] The delay signal generator 110 is used to send a first delay trigger signal to the gas pulse valve 120, and is also used to record the first laser time when the laser excitation module 130 marks the excited molecules and records the second laser time when the laser detection module 140 detects the target ions 180;

[0066] The data processing module 150 is configured to calculate the speed of the target molecule 160 according to the first laser time, the second laser time, and the preset flight distance.

[0067] It should be noted that in order to accurately control the trigger signal timing between the gas pulse valve, laser excitation module and laser detection module so that they meet the specific time interval requirements, this application uses the same delay signal generator to provide delay signals to the gas pulse valve, laser excitation module and laser detection module in the system. Among them, the delay signal generator and the laser excitation module and laser detection module have microsecond and nanosecond level sensitivities to ensure that the molecular excitation and detection frequencies match, so that the flight time of the molecule meets the time difference between excitation and detection, thereby completing the data acquisition of one molecule.

[0068] Therefore, because molecules in a flow field have a certain velocity spread, this application adopts a "mark-and-read" molecular velocity measurement method. This method measures only a very small portion of the molecules in the flow field and uses a highly time-sensitive laser to mark the flying gas molecules. This minimizes the velocity spread of the marked molecules in the flow field, greatly improving the accuracy of molecular velocity measurement. To ensure consistency in the "write" and "read" operations for specific molecules in the flow field, this application uses a time-delay signal generator to precisely control the timing of the system involving multiple laser beams.

[0069] Please note that Figure 2 , Figure 2 This is an optional flow chart of the gas pulse valve provided in the embodiment of the present application. In some embodiments of the present application, the specific execution process of the gas pulse valve may include but is not limited to steps S210 to S220. Figure 2 These two steps are introduced in detail.

[0070] Step S210, receiving a first delayed trigger signal sent by a delayed signal generator, and starting the gas pulse valve according to the first delayed trigger signal;

[0071] In step S220 , the gas pulse valve ejects a gas mass with a broadened velocity, and the gas mass includes the target molecule.

[0072] In some embodiments, during steps S210 to S220, a controller of the gas pulse valve receives a first delayed trigger signal from a delayed signal generator. The delayed signal generator then transmits a first delayed interval corresponding to the first delayed trigger signal to the gas pulse valve. The gas pulse valve then opens and ejects a gas mass with a broadened velocity, the gas mass including multiple target molecules.

[0073] It should be noted that the gas pulse valve of the present application can pulse multiple identical gas boluses to achieve velocity measurement of a target molecule in each gas bolus. Therefore, after measuring the velocity of target molecules in multiple gas boluses, the present application can achieve velocity measurement of all molecules in the entire gas bolus.

[0074] It should be noted that if Figure 3 As shown, Figure 3This is a velocity width distribution diagram of a gas clump (also called a molecular beam) ejected from a gas pulse valve. The gas clump is composed of hydrogen molecules at a measurement temperature of 500K. Each triangle in the diagram represents a target molecule, the horizontal axis represents the velocity of each target molecule in the gas clump, and the vertical axis represents the relative signal intensity of each target molecule in the molecular beam. Furthermore, since molecular velocity broadening follows a Gaussian distribution, and the velocity difference between the two target molecules shown in the figure at half-width is approximately 0.5 km / s, this intuitively illustrates that the gas pulse valve ejects a gas clump with velocity broadening.

[0075] It can be seen that a gas mass ejected by the gas pulse valve includes multiple target molecules with different molecular speeds, and the target molecules with different speeds will gradually form the following according to the speed when flying in the molecular velocity measurement system. Figure 1 The long bar shown, and the right end of the long bar represents the fastest gas mass, and the left end of the long bar represents the slowest gas mass.

[0076] It should be noted that the related technology uses laser-labeled fluorescence detection for velocity measurement. Although the detection time is short, it is highly dependent on the fluorescence lifetime of the molecule being measured. Since the fluorescence of the molecule being measured decays with increasing distance after being labeled, it is difficult to accurately measure some molecules that are difficult to detect by fluorescence or at long flight distances. Based on this, the present application adopts resonance-enhanced multiphoton ionization.

[0077] Specifically, first, the first laser signal of the laser excitation module is set according to the energy transition information of the target molecule. This energy transition information is used to indicate information for transforming the type of target molecule from the ground state v = 0 to the excited state v = 1. Therefore, the first laser signal is used to indicate the laser frequency information required to transform the ground state v = 0 of the target molecule to the excited state v = 1. The present application excites the target molecule according to the laser of the first laser signal to obtain an excited molecule in an excited state.

[0078] It should be noted that the gas clusters of this application can be applied to a variety of different molecular combinations. For example, when a gas cluster contains gas clusters of different molecules, the type of molecule for which velocity measurement is required is first determined. Then, based on the energy transition information of that molecule type, the laser excitation module is tuned to set the first laser signal to meet measurement requirements such as the excitation wavelength. If velocity measurement of another type of molecule is required, the first laser signal of the laser excitation module can be adjusted to achieve laser marking of the different molecules.

[0079] It should be noted that the laser excitation module of the present application can use stimulated Raman pumping or infrared pumping to continuously output to excite the target molecules, thereby achieving nanosecond-level excitation accuracy.

[0080] See also Figure 4 , Figure 4 This is a flowchart of a specific implementation of the laser excitation module provided in the embodiment of the present application. In some embodiments of the present application, the specific implementation process of the laser excitation module may include but is not limited to steps S410 to S430. Figure 4 These three steps are introduced in detail.

[0081] Step S410, setting a first laser signal according to energy transition information of the target molecule;

[0082] Step S420, receiving a second delay trigger signal sent by the delay signal generator, and starting the laser excitation module according to the second delay trigger signal;

[0083] Step S430 , exciting the target molecules in the ground state according to the first laser signal to obtain excited molecules in the excited state.

[0084] In some embodiments, in steps S410 to S430, after setting a first laser signal based on the energy transition information of the target molecule, the delay signal generator sends a second delay signal to the laser excitation module according to the second delay interval corresponding to the second delay trigger signal. The laser excitation module then turns on and continuously outputs to the excitation mark position to excite the target molecule that has flown to the excitation mark position, thereby obtaining an excited molecule in an excited state.

[0085] It should be noted that when the laser excitation module excites the target molecule, the delay signal generator simultaneously records the first laser time when the laser excitation module marks the excited molecule, recorded as t0. This first laser time is also used to represent the time zero point for measuring the speed of the target molecule. Compared with traditional molecular speed measurement devices and methods, this application uses a molecular labeling velocimetry method with a high time resolution laser device to mark the time zero point during the high-speed motion of molecules. This method has an extremely high level of control precision and can significantly reduce the corresponding errors in the measurement results.

[0086] It should be noted that, since different laser frequencies correspond to different energy levels, the laser excitation module can achieve the labeling of molecules when using different laser frequencies to excite the target molecules. At the same time, although the labeling of molecules in this application decays less with the extension of the flight distance, compared with the fluorescent labeling method used in related technologies, the decay rate of this application is slower, which can achieve long-distance molecular speed measurement. At the same time, this application can also accurately measure the speed of molecules such as hydrogen that are difficult to generate fluorescent signals, that is, it has a wider range of applications for molecular speed measurement.

[0087] It should be noted that when the laser excitation module of the present application marks the molecules in the gas mass, it can achieve laser marking of molecules at different positions in the same gas mass by adjusting the second delay interval corresponding to the second delay trigger signal, thereby achieving speed measurement of each molecule in the gas mass.

[0088] See also Figure 1 and Figure 5 In some embodiments of the present application, the laser detection module 140 includes a laser detection unit 141 and an ionization collector 142. The specific execution process of the laser detection module 140 specifically includes but is not limited to steps S510 to S530. Figure 5 These three steps are introduced in detail.

[0089] Step S510: the laser detection unit 141 sets a second laser signal according to the charge separation information of the target molecule 160;

[0090] Step S520 , the laser detection unit 141 ionizes the excited molecules 170 according to the laser light of the second laser signal to obtain target ions 180 ;

[0091] In step S530 , when the ionization collector 142 identifies the target ion 180 , the second laser time for obtaining the target ion 180 is recorded by the delay signal generator 110 .

[0092] In steps S510 to S530 of some embodiments, the laser excitation module of the present application marks the molecules in the gas mass at the excitation marking position, and then excites the molecules to fly forward to fly to the laser detection position. In order to detect the marked excited molecules more sensitively, the present application adopts a resonance enhanced multi-photon ionization method, that is, by tuning the laser detection module so that it outputs a second laser signal that meets the requirements. Then, the excited molecules that fly to the laser detection position are ionized and detected by the laser of the second laser signal, that is, the laser detection unit is used to ionize the excited molecules according to the laser of the second laser signal to obtain target ions. Then, the ionized target ions fly to the ionization collector, and when the ionization collector identifies the target ions, the second laser time of the target ions detected by the laser detection module is recorded by the delay signal generator, which is recorded as T0.

[0093] It should be noted that the charge separation information in this application is used to represent information for removing electrons from excited molecules in the excited state v=1, and the second laser signal is used to represent laser frequency information capable of removing electrons from excited molecules in the excited state. The first laser signal and the second laser signal have different laser frequencies.

[0094] It should be noted that the unlabeled molecules in the gas mass cannot be identified when they fly to the laser detection position of the laser detection module and will not be ionized.

[0095] In some embodiments, before the laser detection module sets the second laser signal according to the charge separation information of the target molecule, the molecular speed measurement system of the present application also includes: receiving a third delay trigger signal sent by the delay signal generator, and starting the laser detection module according to the third delay trigger signal.

[0096] It should be noted that, in this application, after setting the second laser signal, the delay signal generator sends a signal to the laser excitation module according to the third delay interval corresponding to the third delay trigger signal. Then, the laser excitation module turns on and continuously outputs laser light to the laser detection position to ionize the excited molecules flying to the laser detection position, thereby obtaining ionized target ions.

[0097] It should be noted that since the energy of the target ions obtained is relatively weak, the ionization collector of the present application is equivalent to an avalanche amplifier, which can amplify the optical signal of the target ions obtained into an electrical signal that can be recognized by a computer to determine whether the target molecules are successfully ionized, thereby improving the time measurement accuracy.

[0098] It should be noted that this application uses a delay signal generator to send a delay signal to the laser detection module within a reasonable range, and obtains the signal intensity information of the molecules through the data processing module, so that the gas molecule velocity distribution can be calculated based on the time interval between the laser excitation module and the laser detection module and the collected signal intensity.

[0099] See also Figure 1 In some embodiments of the present application, the laser detection unit 141 includes an electrode plate 143 and a laser detector 144. The specific execution process of the laser detection unit 141 ionizing the excited molecules 170 according to the laser of the second laser signal includes:

[0100] When the excited molecule 170 flies to the preset excitation position of the electrode plate 143, the laser detector 144 performs charge separation on the excited molecule 170 according to the laser of the second laser signal to obtain the target ion 180 and the extranuclear electron;

[0101] The target ions 180 and the extranuclear electrons are deflected by the electrode plates 143 , and the target ions 180 are sent to the ionization collector 142 .

[0102] It should be noted that the preset excitation position of the laser detection module of the present application is the laser detection position, which refers to the middle area between the positive plate (+) and the negative plate (-) of the electrode plate 143 where the laser light of the second laser signal intersects. The laser detection position, the excitation mark position, and the gas pulse valve's air outlet are all on the same straight line.

[0103] It should be noted that the present application is used to ionize the labeled excited molecules through the laser detection module to ionize the excited molecules in the excited state into positive ions and electrons. Since positive ions are more massive and easier to distinguish than electrons, the present application uses the ionized positive ions as target ions, and the electrons are extranuclear electrons. Therefore, according to the polarity of the electrode plate, the target ions fly out of the electrode plate in the direction of the negative plate (-) and are collected in the ionization collector. When the ionization collector collects the target ions of the target molecule, the delay signal generator records the second laser time of the target ion detected by the laser detection module. In addition, the extranuclear electrons fly out of the electrode plate in the direction of the positive plate (+).

[0104] It should be noted that the laser detection module of the present application can use stimulated Raman pumping or infrared pumping to continuously output to excite molecules, thereby achieving nanosecond-level laser detection accuracy.

[0105] It should be noted that the preset flight distance in this application is used to represent the distance difference between the laser excitation module and the laser detection module, which is recorded as ΔS. For example, ΔS can be 0.5m, 1m, etc., and is not specifically limited here.

[0106] Therefore, the present application combines laser excitation labeling with laser ionization detection, and uses the ionization collector of the laser detection module to generate ion signals for signal acquisition, thereby replacing the system of fluorescence reading CCD camera in the traditional MTV method, which can effectively simplify the system structure of the molecular velocity measurement system and reduce the structural cost to a certain extent. In addition, the present application adopts the detection method of resonance enhanced multi-photon ionization between laser excitation labeling and laser ionization detection. The time error between the two is at the nanosecond level, and the system structure of the present application can be applied to speed measurements with large ΔS, and has high molecular velocity measurement accuracy.

[0107] It should be noted that the present application is also applicable to the resonance enhanced multi-photon ionization method such as hydrogen, and can also detect single, more dilute molecules, with higher sensitivity in detecting molecular signals.

[0108] It should be noted that, in order to reduce the interference of external gas on the molecular velocity measurement, the molecular velocity measurement system of the present application can be placed in a vacuum chamber, and the vacuum degree can reach 10 -8Torr level. The vacuum chamber features a multi-stage differential vacuum system, where the vacuum level increases sequentially from the beam source of the gas pulse valve to the detection points for laser excitation and laser detection, minimizing interference with detection. Furthermore, the system's alignment can be adjusted using partitions between the multi-stage vacuum chambers.

[0109] It should be noted that the data processing module may be a computer for data processing, that is, the delay signal generator sends the recorded time data to the data processing module to calculate the target speed.

[0110] See also Figure 6 , Figure 6 This is an optional flow chart of the molecular velocity measurement method provided in the embodiment of the present application, which is applied to a molecular velocity measurement system in the above embodiment of the present application. In some embodiments, the molecular velocity measurement method provided in the embodiment of the present application may specifically include but is not limited to steps S610 to S670. Figure 6 These seven steps are introduced in detail.

[0111] Step S610, starting the laser excitation module according to the second delayed trigger signal sent to the laser excitation module by the delayed signal generator;

[0112] Step S620, setting a first laser signal of a laser excitation module according to energy transition information of the target molecule;

[0113] Step S630, exciting the target molecules ejected from the gas pulse valve at a preset excitation position according to the laser of the first laser signal to obtain a first laser time;

[0114] Step S640, receiving a third delayed trigger signal sent by the delayed signal generator to the laser detection module, and starting the laser detection module according to the third delayed trigger signal;

[0115] Step S650, setting a second laser signal of the laser detection module according to the charge separation information of the target molecule;

[0116] Step S660, ionizing the excited molecules at a preset detection position according to the second laser signal to obtain a second laser time;

[0117] Step S670 , performing velocity calculation according to the first laser time, the second laser time and the preset flight distance to obtain a target velocity of the target molecule.

[0118] In some embodiments, in steps S610 to S670, for example, please refer to Figure 1First, the delay signal generator 110 outputs a first delayed trigger signal, that is, outputs a trigger signal with a first delay interval of t1 to the controller of the gas pulse valve 120. The gas pulse valve 120 opens and ejects a gas mass through the time interval t4 to be injected into the interior of the vacuum cavity. The gas mass includes multiple target molecules 160. The emitted target molecules 160 reach the excitation position where they interact with the laser excitation module 130 after a flight time of t5. Among them, the laser excitation module 130 will now set the first laser signal according to the energy transition information of the target molecule, and the delay signal generator 110 outputs a second delayed trigger signal, that is, starts the laser excitation module 130 according to the output trigger signal of the second delay interval t2, and the time when the first laser signal reaches the excitation position where it interacts with the target molecule 160 is t6, and the time t6 is a fixed value. At the same time, the laser detection unit 141 sets the second laser signal according to the charge separation information of the target molecule 160. The delay signal generator 110 outputs a third delayed trigger signal, that is, the laser detection module 140 is started according to the trigger signal of the output third delay interval t3, and the time when the third laser signal reaches the laser detection that interacts with the excited molecule 170 is t7, and the time t7 is a fixed value. Then, when the laser excitation module 130 performs state excitation on the target molecule, the delay signal generator 110 will simultaneously record the first laser time when the laser excitation module 130 marks the excited molecule, recorded as t0. Afterwards, the same wave packet molecule where the marked excited molecule 170 is located arrives at the laser detection position of the laser detection module 140 after a time interval of t8. When the laser detection module 140 ionizes the target molecule, the laser detection unit 141 is used to ionize the excited molecule 170 according to the laser of the second laser signal to obtain the target ion 180. Then, the ionized target ions 180 fly to the ionization collector. When the ionization collector 142 identifies the target ions 180 , the delay signal generator 110 records the second laser time T0 of the target ions detected by the laser detection module 140 .

[0119] It should be noted that the total time it takes for target molecule 160 to reach the designated excitation location and be marked to obtain the excited molecule is t0. To ensure that the first laser signal encounters the target molecule 160 at this location, t2 can be dynamically adjusted to achieve interaction between the target molecule and the laser light of the first laser signal at the excitation location. Similarly, t3 can be dynamically adjusted to achieve interaction between the excited molecule and the laser light of the second laser signal at the laser detection location.

[0120] See also Figure 7 , Figure 7This is an optional flow chart of step S670 provided in the embodiment of the present application. In some embodiments, the preset flight distance is used to represent the mapping distance of the laser excitation module and the laser detection module in the flight direction of the target molecule. Then step S670 may specifically include but is not limited to steps S710 to S720. Figure 7 These two steps are introduced in detail.

[0121] Step S710, determining a laser time difference according to the first laser time and the second laser time;

[0122] Step S720 , performing speed calculation based on the laser time difference and the preset flight distance to obtain a target speed.

[0123] It should be noted that the present application subtracts the first laser time t0 from the second laser time T0 to determine the laser time difference, recorded as Δt. Then, the speed is calculated based on the preset flight distance ΔS and the laser time difference Δt, that is, the target speed of the target molecule is determined according to ΔS / Δt.

[0124] The molecular velocity measurement system provided in the embodiment of the present application includes a laser excitation module and a laser detection module with nanosecond-level sensitivity, which can enable the measurement of the flight time of gas molecules to reach the nanosecond level during the entire process. Compared with the molecular velocity measurement method of the related art, it can accurately and effectively measure the speed of ultrafast gas molecules. In addition, the molecular velocity measurement method of the related art lacks precise control of the time zero point, which makes the measurement result have a certain error, while the embodiment of the present application uses a laser excitation and detection module with high time precision. Therefore, in addition to having the advantages of non-intervention, non-interference, non-contact measurement, high spatiotemporal resolution, and high precision, the present application can also avoid the disadvantage that the fluorescent labeling will continue to attenuate as the distance increases, and it is impossible to perform accurate measurement over long distances. It can be seen that the molecular velocity measurement system provided by the present application can effectively simplify the structure and design cost of the velocity measurement system, and can provide nanosecond-level time control for the entire measurement process, significantly improving the measurement accuracy of ultrafast gas flight speed.

[0125] The present application also provides a computer device comprising: at least one memory, at least one processor, and at least one computer program, wherein the at least one computer program is stored in the at least one memory and the at least one processor executes the at least one computer program to implement any of the molecular velocity measurement methods described in the above embodiments. The computer device can be any intelligent terminal, such as a tablet computer or an in-vehicle computer.

[0126] See also Figure 8 , Figure 8 The hardware structure of a computer device according to another embodiment is shown, and the computer device includes:

[0127] The processor 810 may be implemented as a general-purpose central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits, and is configured to execute relevant programs to implement the technical solutions provided in the embodiments of the present application.

[0128] The memory 820 can be implemented in the form of a read-only memory (ROM), a static storage device, a dynamic storage device, or a random access memory (RAM). The memory 820 can store an operating system and other application programs. When the technical solutions provided in the embodiments of this specification are implemented through software or firmware, the relevant program code is stored in the memory 820 and is called by the processor 810 to execute the molecular velocity measurement method of the embodiments of this application.

[0129] Input / output interface 830, used to implement information input and output;

[0130] Communication interface 840, used to implement communication interaction between this device and other devices, which can be achieved through wired means (such as USB, network cable, etc.) or wireless means (such as mobile network, WiFi, Bluetooth, etc.);

[0131] bus 850 , which transmits information between various components of the device (e.g., processor 810 , memory 820 , input / output interface 830 , and communication interface 840 );

[0132] The processor 810 , the memory 820 , the input / output interface 830 and the communication interface 840 are connected to each other in communication within the device via a bus 850 .

[0133] An embodiment of the present application further provides a computer-readable storage medium, which stores a computer program, and the computer program is used to enable a computer to execute the molecular velocity measurement method in the above embodiment.

[0134] The memory, as a non-transient computer-readable storage medium, can be used to store non-transient software programs and non-transient computer executable programs. In addition, the memory may include a high-speed random access memory and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some embodiments, the memory may optionally include a memory remotely arranged relative to the processor, and these remote memories may be connected to the processor via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0135] The embodiments described in the embodiments of this application are intended to more clearly illustrate the technical solutions of the embodiments of this application and do not constitute a limitation on the technical solutions provided by the embodiments of this application. Those skilled in the art will appreciate that with the evolution of technology and the emergence of new application scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

[0136] Those skilled in the art will understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of the present application, and may include more or fewer steps than shown in the figures, or a combination of certain steps, or different steps.

[0137] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, i.e., they may be located in one place or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of this embodiment.

[0138] Those skilled in the art will appreciate that all or some of the steps in the methods, systems, and functional modules / units in the devices disclosed above may be implemented as software, firmware, hardware, or appropriate combinations thereof.

[0139] The terms "first", "second", "third", "fourth", etc. (if any) in the specification of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0140] It should be understood that in this application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0141] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the above-mentioned units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0142] The units described above as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0143] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0144] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes multiple instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of various embodiments of the present application. The aforementioned storage medium includes: various media that can store programs, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0145] The preferred embodiments of the present invention are described above with reference to the accompanying drawings, but are not intended to limit the scope of the present invention. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and essence of the present invention are intended to be within the scope of the present invention.

Claims

1. A molecular velocity measurement system, characterized in that: The system includes: a delay signal generator, a gas pulse valve, a laser excitation module, a laser detection module and a data processing module, wherein the delay signal generator is respectively connected to the gas pulse valve, the laser excitation module, the laser detection module and the data processing module in communication; wherein, The gas pulse valve is used to eject the target molecules according to the received first delayed trigger signal; The laser excitation module is used to set a first laser signal according to the energy transition information of the target molecule, and to excite the target molecule according to the laser of the first laser signal to obtain an excited molecule; wherein, the laser excitation module is used to set a first laser signal according to the energy transition information of the target molecule, and to excite the target molecule according to the first laser signal to obtain an excited molecule, specifically comprising: setting the first laser signal according to the energy transition information of the target molecule; receiving a second delayed trigger signal sent by a delayed signal generator, and starting the laser excitation module according to the second delayed trigger signal; and exciting the target molecule in the ground state according to the first laser signal to obtain the excited molecule in the excited state; The laser detection module is used to set a second laser signal according to the charge separation information of the target molecule, and ionize the excited molecule according to the laser of the second laser signal to obtain the target ion; wherein the laser detection module includes a laser detection unit and an ionization collector, and the laser detection module is used to set a second laser signal according to the charge separation information of the target molecule, and ionize the excited molecule according to the laser of the second laser signal to obtain the target ion, specifically comprising: the laser detection unit sets the second laser signal according to the charge separation information of the target molecule; the laser detection unit ionizes the excited molecule according to the laser of the second laser signal to obtain the target ion; when the ionization collector identifies the target ion, the second laser time of obtaining the target ion is recorded by a delay signal generator; The delay signal generator is used to send the first delay trigger signal to the gas pulse valve, and is also used to record the first laser time when the laser excitation module marks the excited molecules, and record the second laser time when the laser detection module detects the target ions; The data processing module is used to calculate the speed according to the first laser time, the second laser time and the preset flight distance to obtain the target speed of the target molecule.

2. The system according to claim 1, wherein: The laser detection unit includes an electrode plate and a laser detector. The laser detection unit ionizes the excited molecules according to the laser of the second laser signal to obtain the target ions, including: When the excited molecules fly to the preset excitation position of the electrode plate, the laser detector performs charge separation on the excited molecules according to the laser of the second laser signal to obtain the target ions and extranuclear electrons; The target ions and extranuclear electrons are deflected according to the electrode plates, and the target ions are sent to the ionization collector.

3. The system according to claim 1, wherein: Before the laser detection unit sets the second laser signal according to the charge separation information of the target molecule, the laser detection module is used to set the second laser signal according to the charge separation information of the target molecule, and ionize the excited molecule according to the laser of the second laser signal to obtain target ions, specifically further comprising: Receive the third delay trigger signal sent by the delay signal generator, and start the laser detection module according to the third delay trigger signal.

4. The system according to any one of claims 1 to 3, characterized in that The gas pulse valve is used to eject target molecules according to the received first delayed trigger signal, comprising: receiving the first delay trigger signal sent by the delay signal generator, and starting the gas pulse valve according to the first delay trigger signal; The gas pulse valve ejects a gas mass with a broadened velocity, and the gas mass includes target molecules.

5. A molecular velocity measurement method, applied to a molecular velocity measurement system according to claim 4, characterized in that: The method comprises: Start the laser excitation module according to a second delayed trigger signal sent to the laser excitation module by a delayed signal generator; Setting a first laser signal of the laser excitation module according to the energy transition information of the target molecule; The target molecules ejected from the gas pulse valve are excited at a preset excitation position by the laser of the first laser signal to obtain a first laser time; Starting the laser detection module according to a third delayed trigger signal sent to the laser detection module by the delayed signal generator; Setting a second laser signal of the laser detection module according to the charge separation information of the target molecule; a second laser time obtained by ionizing the excited molecules at a preset detection position according to the second laser signal; Speed ​​calculation is performed according to the first laser time, the second laser time and the preset flight distance to obtain a target speed of the target molecule.

6. The method according to claim 5, characterized in that The preset flight distance is used to represent the mapping distance between the laser excitation module and the laser detection module in the flight direction of the target molecule, and the speed calculation is performed according to the first laser time, the second laser time and the preset flight distance to obtain the target speed of the target molecule, including: determining a laser time difference according to the first laser time and the second laser time; The speed is calculated based on the laser time difference and the preset flight distance to obtain the target speed.

7. A computer device, characterized in that: include: at least one memory; at least one processor; at least one computer program; The at least one computer program is stored in the at least one memory, and the at least one processor executes the at least one computer program to implement: The method according to claim 5 or 6.

8. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and the computer program is used to cause a computer to execute: The method according to claim 5 or 6.

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