Abstract: The invention relates to a method and device for simultaneously measuring mass concentrations of particulates with different sizes. The method detects particulates within different size ranges in air based on laser scattering and can eliminate cross interference between the particulates within different size ranges. The device is simple in structure, can realize on-line simultaneous measurement of PM1.0, PM2.5 and PM10 with high measurement precision and low cost.

Abstract: An ultrasonic gas sensor includes a housing, and a first ultrasonic transducer and a second ultrasonic transducer that are separately arranged at a top of an inner chamber of the housing, where the first ultrasonic transducer and the second ultrasonic transducer form a V-shaped ultrasonic transmission path in the housing; the housing is provided therein with a gas inlet channel and a gas outlet channel; an upper end of the gas inlet channel is close to the first ultrasonic transducer, and an upper end of the gas outlet channel is close to the second ultrasonic transducer, such that a measured gas flow entering a bypass tube passes through a detection area of the first ultrasonic transducer and the second ultrasonic transducer; a lower end of the gas inlet channel and a lower end of the gas outlet channel communicate with a gas sensor mount.

Abstract: The invention provides a gas flow metering gas chamber and a gas flow meter. The gas flow meter includes the gas flow metering gas chamber, a display device and a housing. The gas flow meter gas cell includes a cavity, a gas inlet, a gas outlet, two ultrasonic transducer mounting holes and a reflection device. The signal emitted by the first ultrasonic transducer installed in the first ultrasonic transducer mounting hole and the signal emitted by the second ultrasonic transducer installed in the second ultrasonic transducer mounting hole intersects with each other to form an L-shaped reflection passage. Compared with V-shaped, W-shaped, and N-shaped reflection structures, the effective distance between the two ultrasonic transducers of the present invention more is increased, the cross section of the cavity is reduced, and the rate of the gas flow is increased, which avoids contamination contained in the measured gas to contaminate the ultrasonic transducers and thereby improves the measurement accuracy.

Abstract: A gas analyzer includes a reference gas chamber and a measurement gas chamber in a single cavity, and a micro-flow infrared gas detection device. A water adjustment device is disposed in the micro-flow infrared gas detection device. By identifying the overlapping phenomenon of the absorption spectrums of the gaseous water and the gas to be measured and by taking advantage of the difference between the infrared absorption spectrums of the gaseous water and the gas to be measured, the water adjustment valve is adjusted to change the velocity variation due to the expansion of the gas in front and rear gas chambers and the water adjustment buffer gas chamber of the micro-flow infrared gas detection device, such that the detected infrared spectrum is located within the absorption spectrum of the gas to be measured while away from the absorption spectrum of the gaseous water, thus addressing the water interference issue.

Abstract: The invention relates to a method and device for simultaneously measuring mass concentrations of particulates with different sizes. The method detects particulates within different size ranges in air based on laser scattering and can eliminate cross interference between the particulates within different size ranges. The device is simple in structure, can realize on-line simultaneous measurement of PM1.0, PM2.5 and PM10 with high measurement precision and low cost.

Abstract: The invention provides a gas flow metering gas chamber and a gas flow meter. The gas flow meter includes the gas flow metering gas chamber, a display device and a housing. The gas flow meter gas cell includes a cavity, a gas inlet, a gas outlet, two ultrasonic transducer mounting holes and a reflection device. The signal emitted by the first ultrasonic transducer installed in the first ultrasonic transducer mounting hole and the signal emitted by the second ultrasonic transducer installed in the second ultrasonic transducer mounting hole intersects with each other to form an L-shaped reflection passage. Compared with V-shaped, W-shaped, and N-shaped reflection structures, the effective distance between the two ultrasonic transducers of the present invention more is increased, the cross section of the cavity is reduced, and the rate of the gas flow is increased, which avoids contamination contained in the measured gas to contaminate the ultrasonic transducers and thereby improves the measurement accuracy.

Abstract: A gas analyzer includes a reference gas chamber and a measurement gas chamber in a single cavity, and a micro-flow infrared gas detection device. A water adjustment device is disposed in the micro-flow infrared gas detection device. By identifying the overlapping phenomenon of the absorption spectrums of the gaseous water and the gas to be measured and by taking advantage of the difference between the infrared absorption spectrums of the gaseous water and the gas to be measured, the water adjustment valve is adjusted to change the velocity variation due to the expansion of the gas in front and rear gas chambers and the water adjustment buffer gas chamber of the micro-flow infrared gas detection device, such that the detected infrared spectrum is located within the absorption spectrum of the gas to be measured while away from the absorption spectrum of the gaseous water thus addressing the water interference issue.

Abstract: A method for measuring the component and calorific value of goal gas. The method includes measuring a volume concentration of H2 (TH2) using a thermal conductivity detector (TCD), measuring a volume concentration of O2 using an electrochemical detector (ECD), measuring volume concentrations of CO, CO2, CH4, and CnHm in the coal gas, revising an interference of CH4 in CnHm, revising a measured volume concentration of H2, and calculating the calorific value of the coal gas.

Abstract: A method for measuring the component and calorific value of goal gas. The method includes measuring a volume concentration of H2 (TH2) using a thermal conductivity detector (TCD), measuring a volume concentration of O2 using an electrochemical detector (ECD), measuring volume concentrations of CO, CO2, CH4, and CnHm in the coal gas, revising an interference of CH4 in CnHm, revising a measured volume concentration of H2, and calculating the calorific value of the coal gas.