CN106644667B - System and method for detecting formaldehyde content in air - Google Patents
System and method for detecting formaldehyde content in air Download PDFInfo
- Publication number
- CN106644667B CN106644667B CN201710100866.3A CN201710100866A CN106644667B CN 106644667 B CN106644667 B CN 106644667B CN 201710100866 A CN201710100866 A CN 201710100866A CN 106644667 B CN106644667 B CN 106644667B
- Authority
- CN
- China
- Prior art keywords
- formaldehyde
- temperature
- air
- dry gas
- content
- 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.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/34—Purifying; Cleaning
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/62—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating the ionisation of gases, e.g. aerosols; by investigating electric discharges, e.g. emission of cathode
Abstract
The invention relates to a system and a method for detecting formaldehyde content in air. The system comprises a temperature-control dewatering device and a formaldehyde detection device, wherein a water absorption material and a temperature controller are arranged in the temperature-control dewatering device, the temperature-control dewatering device is provided with an air inlet and a dry air outlet, the formaldehyde detection device is provided with a dry air inlet, and the dry air inlet is connected with the dry air outlet of the temperature-control dewatering device; the method comprises the following steps: sending the air containing formaldehyde into a temperature-control dewatering device, starting a temperature controller, raising the temperature of the temperature-control dewatering device, absorbing water by the air containing formaldehyde through a water absorbing material, raising the temperature to obtain dry air, sending the dry air into a formaldehyde detection device, and detecting the content of formaldehyde in the air. The invention can realize the rapid and direct detection of the formaldehyde content in the air, effectively remove the influence of the moisture in the air, realize the rapid and effective evaluation of the formaldehyde pollution condition in the air, and has convenient and accurate operation and low cost.
Description
Technical Field
The invention relates to a system and a method for directly, quickly and accurately detecting the content of formaldehyde in air.
Background
Formaldehyde is a protoplasmic poison, one of the major pollutants in the air, and has been identified by the World Health Organization (WHO) and the united states Environmental Protection Agency (EPA) as a potentially dangerous carcinogen and an important environmental pollutant. In recent years, there have been many reports on formaldehyde. The formaldehyde has the hazards of carcinogenesis and cancer promotion, and is especially harmful to the old, children and pregnant women with lower immunity. Investigation shows that excessive formaldehyde inhalation for a long time can cause various serious diseases such as nasopharyngeal carcinoma, throat cancer and the like. The harm of formaldehyde to human body is mainly manifested by abnormal smell, irritation, allergy, lung function abnormality, liver function abnormality, immune function abnormality, etc.
When the content of formaldehyde in the air reaches 0.06-0.1 mg/m3When in use, people can feel peculiar smell and discomfort; when the content reaches 0.5-0.6 mg/m3In time, the symptoms of eye stinging, throat discomfort or pain can occur; when the content reaches 30mg/m3Immediately, it will cause death.
The formaldehyde is so harmful that how to detect the content of the formaldehyde quickly and accurately is very important, so that the content of the formaldehyde in the air is effectively removed or reduced. Since formaldehyde is very soluble in water and is volatile, it is difficult to directly measure the formaldehyde content in air. In addition, in the formaldehyde detection process, the final detection result of the formaldehyde content has large deviation due to the influence of moisture in the air.
At present, a great deal of research is carried out on the aspect of analyzing and detecting the formaldehyde content at home and abroad, and a plurality of feasible formaldehyde detection methods are also established. Currently, common methods include: acetylacetone spectrophotometry, chromatography, electrochemical method, and chemical titration. In addition, there are produced various methods such as phloroglucinol method, ion chromatography, infrared spectroscopy, thin layer chromatography, and the like in succession. Although the detection methods can realize the detection of formaldehyde in the air, the detection process is very complicated. For example, the acetylacetone spectrophotometry involves a color reaction, requires periodic calibration of a standard solution, and can only detect formaldehyde in an aqueous phase, which is very inconvenient. Meanwhile, detection methods such as chromatography, infrared spectroscopy and the like need a series of complex pretreatment processes before detection, cannot realize direct detection of formaldehyde in the air, and are susceptible to the influence of moisture in the air. The sensitivity and accuracy of the detection methods are different, and need to be considered comprehensively according to the actual conditions of different monitoring points.
The first prior art discloses a method for measuring gaseous formaldehyde in polyformaldehyde. According to the method, the gaseous formaldehyde is collected into the water phase to form the formaldehyde solution, and the formaldehyde solution is calibrated to perform quantitative determination. The method of the invention has complicated process, can not realize direct quantitative determination of formaldehyde content in the air, and can not eliminate the influence of moisture.
The second prior art discloses a formaldehyde detecting and removing device. The technology is to decompose formaldehyde into CO qualitatively2And H2O, the quantitative detection cannot be completely realized, and the influence of moisture cannot be eliminated.
Disclosure of Invention
The invention aims to provide a system and a method for measuring the content of formaldehyde in air, which can not only eliminate the influence of moisture in air, but also realize direct sample injection detection of formaldehyde, do not need some complex pretreatment processes, do not need early-stage color reaction, and have convenient and quick operation.
The invention provides a system for detecting formaldehyde content in air, which comprises a temperature-control water removal device and a formaldehyde detection device.
The temperature-control dewatering device is internally provided with a water absorbing material and a temperature controller; the temperature control water removal device is provided with an air inlet and a dry air outlet.
The formaldehyde detection device is provided with a dry gas inlet, and the dry gas inlet is connected with a dry gas outlet of the temperature control water removal device.
Further, the system also comprises an air inlet device, and a filter is arranged in the air inlet device. The air inlet device is provided with an air inlet and a filtered air outlet, and the filtered air outlet is connected with the air inlet of the temperature-control water removal device.
Furthermore, the system also comprises an air extractor which is connected with the air inlet device and the temperature-control water removing device and used for conveying the filtered air exhausted by the air inlet device into the temperature-control water removing device.
Furthermore, the system also comprises a formaldehyde enrichment device, and the formaldehyde enrichment device is connected with the temperature control water removal device and the formaldehyde detection device.
Preferably, the system further comprises a solenoid valve,
the air extractor is connected with the temperature-control water removal device through the electromagnetic valve.
The temperature control water removal device is connected with the formaldehyde enrichment device through the electromagnetic valve.
The formaldehyde enrichment device is connected with the formaldehyde detection device through the electromagnetic valve.
The invention also provides a method for detecting the formaldehyde content in the air by using the system, which comprises the following steps:
and sending air containing formaldehyde into the temperature-control dewatering device, starting the temperature controller, raising the temperature of the temperature-control dewatering device, and obtaining dry air after the air containing formaldehyde absorbs moisture through the water absorbing material and is heated.
And sending the dry gas into the formaldehyde detection device to detect the content of formaldehyde.
Preferably, the water-absorbing material is a copolymer of sodium polyacrylate and sodium alginate.
In the method for detecting the formaldehyde content in the air, the temperature of the temperature-control water removal device is controlled to rise to 25-50 ℃.
Further, the method further comprises the steps of:
and feeding the air containing formaldehyde into the air inlet device for filtering to obtain filtered air, and then feeding the filtered air into the temperature-controlled water removal device.
And sending the dry gas into the formaldehyde enrichment device, and sending the dry gas into the formaldehyde detection device until the content of formaldehyde reaches the detection limit of the formaldehyde detection device.
Preferably, when the volume of the dry gas reaches the volume limit of the temperature-control water removal device, the electromagnetic valve is opened, and the dry gas enters the formaldehyde enrichment device. When the formaldehyde enrichment device reaches the volume limit, the electromagnetic valve is opened, and the dry gas enters the formaldehyde detection device.
Compared with the prior art, the method does not need a complex pretreatment process when the content of the formaldehyde in the water-containing air is measured. Moreover, by arranging the temperature-control water removal device, the water in the air can be effectively removed, the formaldehyde is completely in a volatile state, the influence of the water on the determination of the content of the formaldehyde is avoided, and the accuracy of the detection result is ensured.
The system and the method can realize the rapid and direct detection of the formaldehyde content in the air, effectively remove the influence of moisture in the air and realize the rapid and effective evaluation of the formaldehyde pollution condition in the air. The invention has convenient and accurate operation and low cost.
Drawings
FIG. 1 is a schematic diagram of a system for detecting formaldehyde content in air according to an embodiment of the present invention.
FIG. 2 is a schematic flow chart of a method for detecting formaldehyde content in air by using the system shown in FIG. 1 according to an embodiment of the present invention.
The reference numbers in the drawings are as follows:
1. an air intake device;
2. an air extraction device;
3. a temperature control water removal device;
4. a formaldehyde enrichment device;
5. a formaldehyde detection device;
601. solenoid valve, 602, solenoid valve, 603, solenoid valve.
Detailed Description
The following detailed description of the present invention, taken in conjunction with the accompanying drawings and examples, is provided to enable the invention and its various aspects and advantages to be better understood. However, the specific embodiments and examples described below are for illustrative purposes only and are not limiting of the invention.
As shown in fig. 1, a system for detecting formaldehyde content in air according to an embodiment of the present invention includes a temperature-controlled water removal device 3 and a formaldehyde detection device 5. In other embodiments of the present invention, an air intake apparatus 1 is further included. In a different embodiment, a suction device 2 is also included. In other embodiments, further comprising a formaldehyde enrichment device 4. In the preferred embodiment of the present invention, a solenoid valve 601, a solenoid valve 602, and a solenoid valve 603 may be further included.
In the invention, an air inlet device 1, an air exhaust device 2, a temperature control dewatering device 3, a formaldehyde enrichment device 4 and a formaldehyde detection device 5 are connected in sequence. Wherein, an electromagnetic valve 601 is arranged between the air extractor 2 and the temperature-controlled dewatering device 3. An electromagnetic valve 602 is arranged between the temperature control water removal device 3 and the formaldehyde enrichment device 4. Electromagnetic valves 603 are arranged between the formaldehyde enrichment device 4 and the formaldehyde detection device 5. The solenoid valve can realize the automatic control of the gas transmission between the connecting devices.
The air inlet device 1 is provided with a filter, and when impurities in air to be measured are more, fine particles in the air can be filtered and removed. The air intake device 1 has an air inlet and a filtered air outlet.
The temperature control and water removal device 3 is used for receiving the filtered air sent by the air inlet device 1, and is provided with a water absorption material and a temperature controller. Wherein, the water absorbing material is used for absorbing and removing the water in the filtered air. Meanwhile, the temperature controller is used for regulating and controlling the temperature of the temperature-control dewatering device 3, so that the formaldehyde is in a volatile state. The temperature control dewatering device 3 is provided with an air inlet and a dry air outlet. Wherein the air inlet is connected to the filtered air outlet of the air inlet device 1.
The air extractor 2 is arranged between the air inlet device 1 and the temperature-control dewatering device 3 and is connected with the air inlet device 1 and the temperature-control dewatering device 3. The air extracting device 2 can send the filtered air exhausted by the air inlet device 1 into the temperature-controlled dewatering device 3.
The formaldehyde detection device 5 is used for receiving the dry gas sent by the temperature-controlled water removal device 3, so as to detect the content of formaldehyde in the dry gas, namely the content of formaldehyde in the air. The formaldehyde detecting device 5 has a dry gas inlet. Wherein, the dry gas inlet is connected with the dry gas outlet of the temperature-control dewatering device 3. In the present invention, the formaldehyde detecting device 5 is a high-sensitivity, high-resolution formaldehyde detecting apparatus. In some embodiments, the formaldehyde detecting device 5 can be a mass spectrometer.
The formaldehyde enrichment device 4 is used for storing the dry gas sent in by the temperature-control dewatering device 3, so that the content of formaldehyde in the dry gas can reach the detection limit of the formaldehyde detection device 5. The formaldehyde enrichment device 4 is connected with the temperature control dewatering device 3 and the formaldehyde detection device 5.
In the preferred embodiment of the invention, the air extractor 2 is connected with the temperature-controlled water removal device 3 through an electromagnetic valve 601. The temperature control water removal device 3 is connected with the formaldehyde enrichment device 4 through an electromagnetic valve 602. The formaldehyde enrichment device 4 is connected with the formaldehyde detection device 5 through an electromagnetic valve 603.
Fig. 2 is a schematic flow chart illustrating a process of detecting formaldehyde content in air by using the system shown in fig. 1 according to an embodiment of the present invention. The method is realized by the following processes:
air containing formaldehyde is sent to a temperature-controlled dewatering device 3. In the different embodiments of the present invention, for the formaldehyde-containing air containing more impurities, the formaldehyde-containing air is firstly sent into the air inlet device 1, and fine particles in the air are filtered and removed under the action of the filter, so as to obtain the filtered air. In some embodiments, the filtered air may be sent to the temperature-controlled water removal device 3 through the air extraction device 2. As a preferred embodiment of the invention, the filtered gas can be controlled to enter the temperature-controlled water removal device 3 through the electromagnetic valve 601.
The water absorbing material arranged in the temperature control water removing device 3 can effectively absorb and remove the water in the air to be measured. And starting the temperature controller to control the temperature in the water removing device 3 to rise. Since formaldehyde is very soluble in water and starts to volatilize at temperatures above 19 ℃. Therefore, in the invention, the temperature controller controls the temperature in the temperature-controlled dewatering device 3 to be 25-50 ℃, so that all formaldehyde in the air to be detected exists in a gas volatilization state, the complete separation of the formaldehyde and the moisture is realized, and the accuracy of the detection result can be ensured. This step results in a drying gas containing volatile formaldehyde.
The water absorbing material of the invention is a high molecular polymer material which has stronger water absorbing performance and water retention performance and is insensitive to formaldehyde, can effectively absorb water in air, does not react with formaldehyde, and comprises super absorbent resins. In the invention, the water-absorbing material can be sodium polyacrylate or sodium alginate. Preferably, the water-absorbing material of the invention is a copolymer of sodium polyacrylate and sodium alginate.
The dried gas is sent to a formaldehyde detection device 5, and the content of formaldehyde, namely the content of formaldehyde in the air, is detected.
In different embodiments of the present invention, when the formaldehyde content in the air is low or the detection limit of the formaldehyde detection device 5 is high, the dry gas needs to be sent to the formaldehyde enrichment device 4 for storage. And when the content of the formaldehyde in the dry gas reaches the detection limit of the formaldehyde detection device 5 in the formaldehyde enrichment device 4, the dry gas is sent into the formaldehyde detection device 5 to measure the content of the formaldehyde.
The formaldehyde detection device 5 can select detection equipment with high sensitivity and high resolution, such as a mass spectrometer and the like. The invention does not limit the selection of the formaldehyde detection device, and can be selected according to the detection requirements of different embodiments.
In a preferred embodiment of the invention, the delivery of gas between the different devices can be automatically controlled by means of solenoid valves 601, 602, 603. When the volume of the gas in the temperature-control water removal device 3 reaches the volume limit of the device, the electromagnetic valve 602 can be automatically triggered to open, so that the dry gas in the temperature-control water removal device 3 is conveyed to the formaldehyde enrichment device 4. Similarly, when the volume of the gas in the formaldehyde enrichment device 4 reaches the volume limit, the electromagnetic valve 603 can be automatically triggered to open, so that the dry gas is conveyed to the formaldehyde detection device 5.
Finally, it should be noted that: it should be understood that the above examples are only for clearly illustrating the present invention and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications of the invention may be made without departing from the scope of the invention.
Claims (6)
1. A system for detecting the content of formaldehyde in air is characterized by comprising an air inlet device, a temperature-control dewatering device, a formaldehyde enrichment device and a formaldehyde detection device;
the air inlet device is internally provided with a filter and is provided with an air inlet and a filtered air outlet;
the temperature-control dewatering device is internally provided with a water absorbing material and a temperature controller; the temperature control dewatering device is provided with an air inlet and a dry air outlet, and the temperature of the temperature control dewatering device is 25-50 ℃; an air inlet of the temperature-control water removal device is connected with a filtered air outlet of the air inlet device, and a dry air outlet is connected with an inlet of the formaldehyde enrichment device;
the formaldehyde detection device is provided with a dry gas inlet, and the dry gas inlet is connected with an outlet of the formaldehyde enrichment device;
the formaldehyde enrichment device is used for storing the dry gas sent by the temperature-control water removal device.
2. The system of claim 1, further comprising an air extractor connected to the air inlet and the temperature-controlled water removal device for delivering filtered air exhausted from the air inlet into the temperature-controlled water removal device.
3. The system of claim 2, further comprising a solenoid valve,
the air exhaust device is connected with the temperature-control water removal device through the electromagnetic valve;
the temperature control dewatering device is connected with the formaldehyde enrichment device through the electromagnetic valve;
the formaldehyde enrichment device is connected with the formaldehyde detection device through the electromagnetic valve.
4. A method for detecting the formaldehyde content in air by using the system of any one of claims 1-2, comprising the steps of:
feeding air containing formaldehyde into the air inlet device for filtering to obtain filtered air;
sending the filtered air into the temperature-control dewatering device, starting the temperature controller, controlling the temperature of the temperature-control dewatering device to rise to 25-50 ℃, and obtaining dry air after the filtered air absorbs water through the water absorbing material and rises the temperature; and sending the dry gas into the formaldehyde enrichment device, and sending the dry gas into the formaldehyde detection device when the formaldehyde content reaches the detection limit of the formaldehyde detection device, wherein the formaldehyde enrichment device is used for storing the dry gas sent into the temperature control water removal device.
5. The method as claimed in claim 4, wherein the water-absorbing material is a copolymer of sodium polyacrylate and sodium alginate.
6. A method for detecting the formaldehyde content in air by using the system of claim 3, which comprises the following steps:
feeding air containing formaldehyde into the air inlet device for filtering to obtain filtered air;
sending the filtered air into the temperature-control dewatering device, starting the temperature controller, controlling the temperature of the temperature-control dewatering device to rise to 25-50 ℃, and obtaining dry air after the filtered air absorbs water through the water absorbing material and rises the temperature; sending the dry gas into the formaldehyde enrichment device, and sending the dry gas into the formaldehyde detection device to detect the content of formaldehyde until the content of formaldehyde reaches the detection limit of the formaldehyde detection device, wherein the formaldehyde enrichment device is used for storing the dry gas sent by the temperature-controlled water removal device;
when the volume of the dry gas reaches the volume limit of the temperature-control water removal device, the electromagnetic valve is opened, and the dry gas enters the formaldehyde enrichment device;
when the formaldehyde enrichment device reaches the volume limit, the electromagnetic valve is opened, and the dry gas enters the formaldehyde detection device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710100866.3A CN106644667B (en) | 2017-02-23 | 2017-02-23 | System and method for detecting formaldehyde content in air |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710100866.3A CN106644667B (en) | 2017-02-23 | 2017-02-23 | System and method for detecting formaldehyde content in air |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106644667A CN106644667A (en) | 2017-05-10 |
| CN106644667B true CN106644667B (en) | 2022-02-01 |
Family
ID=58846609
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710100866.3A Active CN106644667B (en) | 2017-02-23 | 2017-02-23 | System and method for detecting formaldehyde content in air |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106644667B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110466307B (en) * | 2018-05-09 | 2024-04-09 | 江苏日盈电子股份有限公司 | In-vehicle air quality control system and method and vehicle |
| CN110470792A (en) * | 2018-05-09 | 2019-11-19 | 江苏日盈电子股份有限公司 | Air quality acquisition methods and air quality obtain system |
| CN210071766U (en) * | 2018-07-31 | 2020-02-14 | 常州承信投资合伙企业(有限合伙) | Vehicle with air purification device and air quality detection device |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201311379Y (en) * | 2008-12-15 | 2009-09-16 | 济南海纳特科技有限公司 | Formaldehyde tester of wood-based plates by gas analyzing method |
| CN201517972U (en) * | 2009-09-25 | 2010-06-30 | 东莞市升微机电设备科技有限公司 | Test system for detecting volatile organics |
| CN101858876A (en) * | 2010-06-01 | 2010-10-13 | 东莞市升微机电设备科技有限公司 | Detecting system and humidity detecting method for detecting volatile organic compound |
| CN103727598A (en) * | 2013-12-20 | 2014-04-16 | 杨海基 | Device for removing indoor formaldehyde |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1257398C (en) * | 2004-05-11 | 2006-05-24 | 南京林业大学 | Pumping measurement method for formaldehyde release quantity of artificial board |
-
2017
- 2017-02-23 CN CN201710100866.3A patent/CN106644667B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201311379Y (en) * | 2008-12-15 | 2009-09-16 | 济南海纳特科技有限公司 | Formaldehyde tester of wood-based plates by gas analyzing method |
| CN201517972U (en) * | 2009-09-25 | 2010-06-30 | 东莞市升微机电设备科技有限公司 | Test system for detecting volatile organics |
| CN101858876A (en) * | 2010-06-01 | 2010-10-13 | 东莞市升微机电设备科技有限公司 | Detecting system and humidity detecting method for detecting volatile organic compound |
| CN103727598A (en) * | 2013-12-20 | 2014-04-16 | 杨海基 | Device for removing indoor formaldehyde |
Also Published As
| Publication number | Publication date |
|---|---|
| CN106644667A (en) | 2017-05-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106644667B (en) | System and method for detecting formaldehyde content in air | |
| CN111766182B (en) | System and method for detecting particulate matter emission in engine tail gas | |
| CN110244031B (en) | Wood-based plate VOC releases survey device | |
| CN204556457U (en) | A kind of stationary pollution source PM2.5 discharges continuous monitor system | |
| CN102103128A (en) | Method for determining contents of formaldehyde, acetaldehyde and acetone in water-borne adhesives for cigarettes | |
| CN103364484A (en) | Cigarette mainstream smoke on-line analysis device and method | |
| CN103471879A (en) | Smoke gas collecting device and method for quickly and accurately determining seven heavy metals in smoke gas | |
| CN103278589A (en) | Detection method and device for volatile and semi-volatile components | |
| CN104237431A (en) | Method for measuring TSNAs (tobacco-specific nitrosamines) in electronic cigarette smoke | |
| CN104165969B (en) | A kind of pollution source sulfur dioxide (SO2) emissions on-line monitoring system and method | |
| WO2020248526A1 (en) | Exhaust gas test device for fuel cell vehicle | |
| CN104483339B (en) | On-line analyzer and analysis method of mercury in flue gas based on wet enrichment | |
| CN107153022A (en) | A kind of online coke oven flue gas analytical instrument pretreatment system | |
| CN107894491A (en) | Test the device and method of water soluble ion concentration in wet desulphurization neat stress | |
| CN110320292A (en) | The measuring method of volatile component in a kind of full flue gas of electronic cigarette | |
| CN106802326A (en) | The detection method of the content of VOC in electronic cigarette atomizing vapour | |
| CN113777210A (en) | Method for simultaneously detecting water-soluble anion and cation contents in atmosphere-particles by using rapid solvent extraction-ion chromatography | |
| CN106066352A (en) | A kind of sulfur hexafluoride gas trace moisture content determinator and method thereof | |
| Griffith et al. | Improved steam-distillation apparatus | |
| JP2003302316A (en) | Oil analyzing-method and oil analyzer | |
| CN110850022A (en) | Method for detecting quality of Shuangdong capsule | |
| CN109738584A (en) | A kind of electric nasus system | |
| CN211292803U (en) | VOCs gas detection device | |
| CN108318300A (en) | A kind of vehicle-mounted gas detector sampling probe | |
| CN213715153U (en) | VOCs detection device in waste gas |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |