CN111307247A - Self-powered water level monitoring device and monitoring method - Google Patents
Self-powered water level monitoring device and monitoring method Download PDFInfo
- Publication number
- CN111307247A CN111307247A CN201910143345.5A CN201910143345A CN111307247A CN 111307247 A CN111307247 A CN 111307247A CN 201910143345 A CN201910143345 A CN 201910143345A CN 111307247 A CN111307247 A CN 111307247A
- Authority
- CN
- China
- Prior art keywords
- water level
- electrode
- self
- distributed
- electrodes
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
- G01F23/22—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water
- G01F23/24—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of resistance of resistors due to contact with conductor fluid
- G01F23/241—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of resistance of resistors due to contact with conductor fluid for discrete levels
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02N—ELECTRIC MACHINES NOT OTHERWISE PROVIDED FOR
- H02N1/00—Electrostatic generators or motors using a solid moving electrostatic charge carrier
- H02N1/04—Friction generators
Landscapes
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Fluid Mechanics (AREA)
- General Physics & Mathematics (AREA)
- Measurement Of Levels Of Liquids Or Fluent Solid Materials (AREA)
Abstract
The invention discloses a self-powered water level monitoring device and a monitoring method, which are applied to a solid-liquid friction nano generator for water level sensing, wherein the measuring device comprises a friction nano generator unit and a signal analysis unit, the friction nano generator unit comprises a water container 2, a protective sleeve 5 and a metal electrode, the metal electrode comprises a main electrode 1 and distributed electrodes 4, the main electrode 1 is arranged at the upper end of the water container 2, the distributed electrodes 4 are arranged at the lower end of the water container 2 at equal intervals, the protective sleeve is arranged outside the metal electrode and the water container 2, the friction nano generator unit outputs voltage signals due to the water level changes, the device obtains the water level changes by analyzing the changes of the voltage signals, and can monitor the water level in real time.
Description
Technical Field
The invention relates to a monitoring device, in particular to a self-powered water level monitoring device and a monitoring method.
Background
Along with the development of intelligent ships, ship draft monitoring has important meaning to guaranteeing ship stability, security, improving ship efficiency and preventing ship overturning and other water traffic accidents. The draught measurement of the traditional navigation ship is a means of manually observing the mark of the ship draught line. The randomness is large, observation errors exist, and real-time monitoring cannot be achieved; for old ships, the waterline is affected by factors such as seawater corrosion, mud and sand abrasion, shedding, oil dirt pollution and the like, and is difficult to identify, so that the measurement accuracy is greatly influenced.
Therefore, a novel ship draft monitoring device which can accurately monitor in real time, is self-powered and has high durability is needed to be invented, the requirement of ship draft measurement is met, the purposes of adjusting the navigation attitude, reducing the navigation energy consumption and guaranteeing the navigation safety are achieved, and the ship intellectualization is realized.
Disclosure of Invention
The invention provides a self-powered water level monitoring device based on a friction nano generator, which directly converts water level change into an electric signal for analysis and processing and can monitor the water level in real time.
In order to achieve the above object, the present invention provides a self-powered water level monitoring apparatus, comprising a friction nanogenerator unit and a signal analysis unit, wherein the friction nanogenerator unit comprises,
the water-containing capacitor comprises a water-containing container, a main electrode and a distributed electrode, wherein the main electrode is arranged at the upper end of the outer wall of the water-containing container, the distributed electrode comprises a plurality of sub-electrodes, and the plurality of sub-electrodes are arranged at the lower end of the outer wall of the water-containing container in an up-down sequence;
the signal analysis unit is connected between the main electrode and the distributed electrode;
when the water fluctuates in the water container, the signal analysis unit detects the potential difference between the main electrode and the distributed electrode, and the signal analysis unit obtains the water level change according to the potential difference.
Preferably, the interval between each sub-electrode of the distributed electrode is the same, and preferably, the interval ranges from 1mm to 50 mm.
Preferably, each electrode width of the distributed electrodes ranges from 1mm to 50 mm.
Preferably, the water container is a tubular body or a cylindrical body.
Preferably, the device further comprises a protective sleeve, wherein the protective sleeve is arranged at the outer ends of the water container and the main electrode;
and/or the protective sleeve is a tubular body or a columnar body.
Preferably, the main electrode and the distributed electrode are arranged around the outer surface of the water container in a circle.
Preferably, the water container is made of polytetrafluoroethylene, nylon, silica gel or polyimide.
Preferably, the material of the protective sleeve is polytetrafluoroethylene, nylon, silica gel or polyimide.
Preferably, the main electrode and the distributed electrode are both strip-shaped and horizontally arranged on the outer wall of the water container.
Preferably, the signal analyzing unit includes a voltage signal detecting element, a low pass filter, and a signal analyzing device.
Preferably, the signal analysis device further comprises a resistor connected between the distributed electrode and a main electrode, and the signal analysis unit is connected to two ends of the resistor; preferably, the resistance is in the range of 100M Ω -1000M Ω.
Correspondingly, the invention also provides a self-powered water level monitoring method, which adopts any one of the self-powered water level monitoring devices, wherein,
the distributed electrodes and the main electrodes are in open circuit, when the water level rises or falls, the signal analysis unit monitors that voltage signals between the distributed electrodes and the main electrodes are in stepped rising or falling, when the water level passes through gaps between the distributed sub-electrodes and the sub-electrodes, the voltage growth rates are different, and the position of the water level is obtained through a voltage waveform diagram.
Preferably, the signal analysis unit performs filtering processing on the voltage signal, and then obtains a dv/dt curve by deriving time, when the water level fluctuates, there is a peak every time the water level passes through an electrode, and there is a trough every time the water level passes through a gap, and the position of the water level is obtained through a dv/dt curve oscillogram.
The invention also provides a self-powered water level monitoring method, which adopts the self-powered water level monitoring device, wherein,
the distributed electrodes are connected with the main electrode through resistors, the signal analysis unit monitors voltages at two ends of the resistors, when the water level fluctuates, the voltage changes every time the water level passes through one electrode or one gap, and the position of the water level is obtained through the change of the voltage signals.
Compared with the prior art, the invention has the following beneficial effects:
1. the self-powered water level sensor based on the friction nano generator is formed by the water container, the main electrode and the distributed electrodes, the water level change is directly converted into an electric signal for analysis and processing, and the water level can be monitored in real time.
2. The designed friction nanometer generator unit can flexibly design the size according to the actual condition of the ship and enhance voltage and current signals.
3. Under the environment of any wave frequency and water quality, the water level signal can be accurately transmitted, and the device can adapt to different sea conditions.
4. The invention has simple structure, the high polymer material used by the water container has good hydrophobicity, and the influence of seawater corrosion on the output signal of the device can be reduced if the high polymer material is sealed at the outer side of the friction nano generator.
5. As a self-powered water level monitoring device, the invention utilizes a sensor to automatically sense and obtain water level information, and combines the current automatic control technology, and the big data processing and analyzing technology can be directly applied to intelligent ships and unmanned ships.
For the above reasons, the present invention can be widely applied to the field of ships.
Drawings
FIG. 1 is a schematic view of the structure of the present invention
FIG. 2 is a schematic diagram of the power generation principle of the present invention
FIG. 3 is a signal analysis diagram of the present invention
FIG. 4 is a graph of dv/dt characteristic change analysis according to the present invention
FIG. 5 is a graph of the characteristic change of resistance voltage according to the present invention
Description of the reference numerals
1 main electric level 2 water container
3 water level 4 distributed electrode to be measured
5 protective sleeve
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, 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 some, but not all, embodiments of the present invention. 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.
As shown in fig. 1 to 3, a typical structure of the self-powered water level monitoring apparatus includes a friction nano-generator unit and a signal analysis unit, and the friction nano-generator unit is connected with the signal analysis unit. The friction nanometer generator unit comprises a water container 2, a protective sleeve 5, a main electrode 1 and a distributed electrode 4, wherein the main electrode 1 is arranged at the upper end of the outer wall of the water container 2, the distributed electrode 4 comprises a plurality of sub-electrodes, and the plurality of sub-electrodes are arranged at the lower end of the outer wall of the water container 2 in an up-down sequence; the signal analyzing unit (not shown in the figure) includes a voltage signal detecting element, a low-pass filter, and a signal analyzing device.
The voltage signal detection element, the low-pass filter and the signal analysis equipment form a signal analysis unit for detecting and analyzing signals of the monitoring device. The voltage signal detection element is used for detecting a voltage signal output by the monitoring device, the low-pass filter is used for filtering noise in the signal, and the signal analysis equipment is used for sensor signal derivation and other operations.
Taking the example that the water container 2 adopts a PTFE circular tube, and the main electrode and the distributed electrode all adopt copper, the working principle of the invention is as follows: before the water level 3 enters the PTFE round pipe 2, the water level monitoring device is in an electrostatic equilibrium state. After water level 3 got into PTFE pipe 2, water can take place the friction with PTFE, produces the triboelectric charge, because the electron adsorption capacity of water is less than PTFE, PTFE can take on the negative charge, and then can respond to out the positive charge on the copper electrode, and water also can take on the positive charge for PTFE, because PTFE is the electret, so the negative charge can remain on the PTFE surface. When water flows through the first sub-electrode, the electrostatic balance is disrupted due to the positive charge of the water. The non-electrostatic equilibrium creates a potential difference between the main electrode 1 and the distribution electrode 4, resulting in the transfer of electrons from the distribution electrode to the main electrode, creating a current in the external circuit. Similarly, when the water level 3 passes through the second and third sub-electrodes, the positive charges induced on the distributed electrode flow to the main electrode through the external circuit to form a current.
The interval between each sub-electrode of the distributed electrode is the same, preferably, the interval range is 1 mm-50 mm; the width of each electrode of the distributed electrode ranges from 1mm to 50 mm.
The main electrode 1 and the distributed electrode 4 can be both in strip shapes and are horizontally arranged on the outer wall of the water container 2. The water container 2 may be a tubular body or a columnar body, or may be an irregular structure such as a U-shaped pipe. When the tube-containing water container 2 is a tubular body, the radial dimension range is 5 mm-20 mm. The main electrode 1 and the distributed electrode 4 are arranged around the outer surface of the tubular water container in a circle.
The material of the water container 2 is polytetrafluoroethylene, nylon, silica gel or polyimide, and the like, and preferably adopts hydrophobic material.
The protective sleeve 5 is of an optional structure, is made of polytetrafluoroethylene, nylon, silica gel or polyimide and the like, and is preferably made of a hydrophobic material.
The process of monitoring the water level using the self-powered water level monitoring apparatus of the present invention will be described below.
In embodiment 1, when the distributed electrode and the main electrode are open-circuited and the water level rises or falls, the signal analysis unit monitors that the voltage signal between the distributed electrode and the main electrode rises in a stepwise manner, as shown in fig. 3. When the water level passes through the sub-electrodes, the voltage increases faster, and when the water level passes through the gaps between the sub-electrodes, the voltage increases less. This is because the water level can induce more charges on the electrodes when passing through the sub-electrodes, and less charges when passing through the gaps. The position of the water level can be obtained by the voltage waveform diagram.
Further, when the bit between the distributed electrode and the main electrode is open, the low-pass filter performs filtering processing on the open-circuit voltage signal, and then performs derivation on time to obtain a dv/dt curve, as shown in fig. 4. When the water level rises, a rising positive value wave crest can be generated when the water level passes through one sub-electrode, and a positive value wave trough can be generated when the water level passes through one gap; when the water level descends, the water level has a negative value wave trough every time the water level passes through one sub-electrode, and has a negative value wave crest every time the water level passes through one gap. When the water level passes through the electrodes, the voltage increases rapidly, and the slope is larger; when the water level passes through the gap, the voltage is increased slightly, and the slope is small. And obtaining the position of the water level through a dv/dt curve waveform diagram. In embodiment 2, when a 100M Ω -1000M Ω resistor is connected between the distributed electrodes and the main electrodes, the signal analysis unit monitors voltage signals at two ends of the resistor as shown in fig. 5, when the water level rises, the voltage rises by a certain value every time the voltage passes through one sub-electrode, and when the voltage passes through one gap, the voltage drops by a certain value; when the water level is lowered, the voltage is lowered by a certain value every time the voltage passes through one sub-electrode, and the voltage is raised by a certain value every time the voltage passes through one gap. The position of the water level can be directly obtained through the change of the voltage signal. Since the charge is transferred between the main electrode and the distributed electrode via the resistor when the water level passes the sub-electrode, substantially no charge is transferred when passing the gap.
Through experimental exploration, the voltage is basically unrelated to the rising speed of the water level, namely the voltage is unrelated to the water level change frequency. The salinity of the liquid is increased, so that the voltage is reduced, and the characteristic rule of the liquid is not influenced, namely the open-circuit voltage, the resistance voltage and the dv/dt characteristic are not changed. Meanwhile, the water level monitoring resolution can be improved by reducing the width and the gap of the electrodes.
The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention. Such as variations in the shape, material, and dimensions of the various components.
It should be noted that the various features described in the above embodiments may be combined in any suitable manner without departing from the scope of the invention. The invention is not described in detail in order to avoid unnecessary repetition. In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.
Claims (14)
1. A self-powered water level monitoring device is characterized by comprising a friction nano generator unit and a signal analysis unit, wherein the friction nano generator unit comprises,
the water-containing capacitor comprises a water-containing container, a main electrode and a distributed electrode, wherein the main electrode is arranged at the upper end of the outer wall of the water-containing container, the distributed electrode comprises a plurality of sub-electrodes, and the plurality of sub-electrodes are arranged at the lower end of the outer wall of the water-containing container in an up-down sequence;
the signal analysis unit is connected between the main electrode and the distributed electrode;
when the water fluctuates in the water container, the signal analysis unit detects the potential difference between the main electrode and the distributed electrode, and the signal analysis unit obtains the water level change according to the potential difference.
2. The self-powered water level monitoring device according to claim 1, wherein the spacing between each sub-electrode of the distributed electrode is the same, preferably, the spacing is in the range of 1mm to 50 mm.
3. The self-powered water level monitoring device according to claim 1 or 2, wherein each electrode width of the distributed electrodes ranges from 1mm to 50 mm.
4. A self-powered water level monitoring device according to any one of claims 1 to 3 wherein the water containing vessel is a tubular or cylindrical body.
5. The self-powered water level monitoring device according to claim 4, further comprising a protective sleeve disposed at an outer end of the water containing container and the main electrode;
and/or the protective sleeve is a tubular body or a columnar body.
6. A self-powered water level monitoring device according to claim 4 or 5 wherein the main and distributed electrodes are disposed around the outer surface of the water containing vessel.
7. The self-powered water level monitoring device according to any one of claims 1 to 5, wherein the material of the water containing vessel is polytetrafluoroethylene, nylon, silica gel or polyimide.
8. The self-powered water level monitoring device of claim 5, wherein the protective sleeve is made of polytetrafluoroethylene, nylon, silicone or polyimide.
9. The self-powered water level monitoring device according to claims 1 to 8, wherein the main electrode and the distribution electrode are both elongated and horizontally disposed on the outer wall of the water containing vessel.
10. The self-powered water level monitoring device according to any one of claims 1 to 9, wherein the signal analyzing unit comprises a voltage signal detecting element, a low pass filter and a signal analyzing device.
11. The self-powered water level monitoring device according to any one of claims 1 to 8, further comprising a resistor connected between the distributed electrode and a main electrode, the signal analysis unit being connected across the resistor;
preferably, the resistance is in the range of 100M Ω -1000M Ω.
12. The self-powered water level monitoring method, characterized in that the self-powered water level monitoring apparatus of any one of claims 1 to 9 is used, wherein,
the distributed electrodes and the main electrodes are in open circuit, when the water level rises or falls, the signal analysis unit monitors that voltage signals between the distributed electrodes and the main electrodes are in stepped rising or falling, when the water level passes through gaps between the distributed sub-electrodes and the sub-electrodes, the voltage growth rates are different, and the position of the water level is obtained through a voltage waveform diagram.
13. The monitoring method according to claim 10,
and the signal analysis unit carries out filtering processing on the voltage signal, then obtains a dv/dt curve by differentiating time, when the water level fluctuates, a peak exists when the water level passes through one electrode, a trough exists when the water level passes through one gap, and the position of the water level is obtained through a dv/dt curve oscillogram.
14. The self-powered water level monitoring method, characterized in that the self-powered water level monitoring apparatus of any one of claims 1 to 9 is used, wherein,
the distributed electrodes are connected with the main electrode through resistors, the signal analysis unit monitors voltages at two ends of the resistors, when the water level fluctuates, the voltage changes every time the water level passes through one electrode or one gap, and the position of the water level is obtained through the change of the voltage signals.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910143345.5A CN111307247A (en) | 2019-02-26 | 2019-02-26 | Self-powered water level monitoring device and monitoring method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910143345.5A CN111307247A (en) | 2019-02-26 | 2019-02-26 | Self-powered water level monitoring device and monitoring method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111307247A true CN111307247A (en) | 2020-06-19 |
Family
ID=71156659
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910143345.5A Pending CN111307247A (en) | 2019-02-26 | 2019-02-26 | Self-powered water level monitoring device and monitoring method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111307247A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113155008A (en) * | 2021-03-10 | 2021-07-23 | 广东化一环境科技有限公司 | Thickness detection equipment and detection method for layered medium |
| CN113300629A (en) * | 2021-06-11 | 2021-08-24 | 大连海事大学 | Compressed air power generation device based on friction nanometer power generation |
| CN113556059A (en) * | 2021-08-30 | 2021-10-26 | 上海大学 | Energy collector combining piezoelectric and friction nano power generation based on vortex-induced vibration |
| CN114337353A (en) * | 2021-12-31 | 2022-04-12 | 武汉大学 | Tubular single-electrode structure friction nano generator, preparation method thereof, performance testing device and performance testing method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103780123A (en) * | 2013-02-01 | 2014-05-07 | 国家纳米科学中心 | Sliding friction nanometer generating set and generating set |
| CN105450079A (en) * | 2014-09-30 | 2016-03-30 | 北京纳米能源与系统研究所 | Vibration energy collector and intelligent flowmeter |
| CN107782406A (en) * | 2017-11-23 | 2018-03-09 | 大连海事大学 | A kind of level sensor based on friction electric induction |
| CN107860437A (en) * | 2017-12-18 | 2018-03-30 | 大连海事大学 | A kind of circular pipe type liquid level sensor |
| CN207439502U (en) * | 2017-11-23 | 2018-06-01 | 大连海事大学 | A kind of water level sensor based on friction electric induction |
-
2019
- 2019-02-26 CN CN201910143345.5A patent/CN111307247A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103780123A (en) * | 2013-02-01 | 2014-05-07 | 国家纳米科学中心 | Sliding friction nanometer generating set and generating set |
| CN105450079A (en) * | 2014-09-30 | 2016-03-30 | 北京纳米能源与系统研究所 | Vibration energy collector and intelligent flowmeter |
| CN107782406A (en) * | 2017-11-23 | 2018-03-09 | 大连海事大学 | A kind of level sensor based on friction electric induction |
| CN207439502U (en) * | 2017-11-23 | 2018-06-01 | 大连海事大学 | A kind of water level sensor based on friction electric induction |
| CN107860437A (en) * | 2017-12-18 | 2018-03-30 | 大连海事大学 | A kind of circular pipe type liquid level sensor |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113155008A (en) * | 2021-03-10 | 2021-07-23 | 广东化一环境科技有限公司 | Thickness detection equipment and detection method for layered medium |
| CN113300629A (en) * | 2021-06-11 | 2021-08-24 | 大连海事大学 | Compressed air power generation device based on friction nanometer power generation |
| CN113556059A (en) * | 2021-08-30 | 2021-10-26 | 上海大学 | Energy collector combining piezoelectric and friction nano power generation based on vortex-induced vibration |
| CN113556059B (en) * | 2021-08-30 | 2022-06-17 | 上海大学 | Energy collector combining piezoelectric and friction nano power generation based on vortex-induced vibration |
| US11863088B2 (en) | 2021-08-30 | 2024-01-02 | Shanghai University | Vortex-induced vibration-based piezoelectricity and friction nanometer power generation combined energy collector |
| CN114337353A (en) * | 2021-12-31 | 2022-04-12 | 武汉大学 | Tubular single-electrode structure friction nano generator, preparation method thereof, performance testing device and performance testing method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111307247A (en) | Self-powered water level monitoring device and monitoring method | |
| CN101566491B (en) | Method and system for measuring liquid level of conductive liquid | |
| CN108692713A (en) | A kind of wave monitoring system and its working method | |
| CN103776511A (en) | Level information monitoring method, device and system | |
| CN113549918A (en) | Contact type measuring device and method for sacrificial anode cathodic protection state of offshore submarine pipeline | |
| CN101028573A (en) | Water conductivity monitoring circuit for use with a steam generator | |
| CN106352948A (en) | Novel capacitive-sensor liquid level detection system and method | |
| CN106560709B (en) | Happen suddenly water pollution source traceability system and method | |
| US4297640A (en) | Apparatus for measuring the electric charge condition of non-conductive particles in a mildly conductive electrolyte | |
| CN201438127U (en) | Precise liquid level sensor | |
| CN116625325B (en) | Working method of three-dimensional natural potential monitoring device for seepage in seabed | |
| CN208383126U (en) | A kind of wave monitoring system | |
| CN204255283U (en) | Existing field real-time measurement offshore oil film thickness device | |
| CN104482853A (en) | Device and method for on-site real-time measurement of at-sea oil film thickness | |
| US4319484A (en) | Linear response capacitance wave height measuring system | |
| CN111189881A (en) | Two-phase flow grid sensor visualization method based on differential measurement mode | |
| CN111664911A (en) | System and method for detecting mud-water interface in thickener | |
| JP5464548B2 (en) | Measurement method of fresh salt water interface | |
| CA1304602C (en) | Apparatus for and method of determining liquid flow in open channels and conduits | |
| CN210605007U (en) | Underwater detector water outlet monitoring circuit based on field learning method | |
| CN206488894U (en) | A kind of oily leak detection warning device of high-frequency sasser capacitance method | |
| CN207197630U (en) | Three electric pole type drilling water level intelligent monitors | |
| CN201440134U (en) | Electrochemistry measuring probe | |
| CN106560714B (en) | Large-scale plant that raises overstandard waste water emission early-warning method | |
| US4173888A (en) | Peak point detector for ionized mass flow rate measurement |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB02 | Change of applicant information | ||
| CB02 | Change of applicant information |
Address after: No.8, yangyandong 1st Road, Yanqi Economic Development Zone, Huairou District, Beijing Applicant after: Beijing Institute of Nanoenergy and Nanosystems Address before: 100083, C building, Tiangong building, No. 30, Haidian District, Beijing, Xueyuan Road Applicant before: Beijing Institute of Nanoenergy and Nanosystems |