An analytical system and method for detecting volatile organic chemicals in water including a coated SAW detector that provides for improved reduction of moisture at the coating of the SAW detector. A stabilized SAW sensitivity and long lasting calibration is achieved. The analytical system further includes an improved sample vessel and sparger that allow for easy grab sample analysis, while also providing efficient purging of the volatile organic compounds from the water sample. In addition, an improved preconcentrator provides a stabilized sorbent bed.

According to improvement of the receptor layer of various sensors of the type for detecting physical parameters (for example, a surface stress sensor, QCM, and SPR), all of high sensitivity, selectivity, and durability are achieved simultaneously. A porous material or a particulate material, e.g., nanoparticles, is used in place of a uniform membrane which has been conventionally used as a receptor layer. Accordingly, the sensitivity can be controlled by changing the membrane thickness of the receptor layer, the selectivity can be controlled by changing a surface modifying group to be fixed on the porous material or particulate material, and the durability can be controlled by changing the composition and surface properties of the porous material or particulate material.

A reference chamber for a fluid sensor comprises a housing, a deflectable structure, which is arranged movably within the housing, a control device configured to drive the deflectable structure at a first point in time such that the deflectable structure assumes a defined position, and to drive the deflectable structure at a second point in time such that the deflectable structure moves out of the defined position and a movement of the deflectable structure in the housing is obtained. The reference chamber comprises an evaluation device configured to determine a movement characteristic of the movement of the deflectable structure on the basis of the moving into the defined position or on the basis of the moving out of the defined position and to determine an atmospheric property in the housing on the basis of the movement characteristic.

A gas detection device according to an embodiment of the present invention includes a casing and a plurality of sensor elements. The casing includes a gas introducing port, a first chamber that communicates with the introducing port, a second chamber that communicates with the first chamber, a flow limiter that limits a flow of gas from the first chamber to the second chamber, and a gas exhausting portion that communicates with the second chamber. The plurality of sensor elements are disposed within the second chamber and have different detection sensitivities depending on a gas type.

A variable value calculating process includes: measuring a propagation time of the propagation of an ultrasound wave through a measurement sector inside a housing; obtaining a temperature calculated value on the basis of the measured value of the propagation time and a reference distance for the measurement sector; obtaining a temperature measured value by measuring the temperature inside the housing; and obtaining a temperature replacement fluctuation value indicating a difference between the temperature calculated value and the temperature measured value. The variable value calculating process is executed for each of a plurality of temperature conditions under which the temperature of a reference gas inside the housing differs. A temperature compensation table in which the temperature of a gas to be measured is associated with a temperature compensation value relating to the temperature is obtained on the basis of the temperature replacement fluctuation values obtained under each temperature condition.

A method is disclosed. In one example, the method includes bonding a first panel of a first material to a base panel in a first gas atmosphere, wherein multiple hermetically sealed first cavities encapsulating gas of the first gas atmosphere are formed between the first panel and the base panel. The method further includes bonding a second panel of a second material to at least one of the base panel and the first panel, wherein multiple second cavities are formed between the second panel and the at least one of the base panel and the first panel.

A gas sensor (100,200) includes at least one sensor device including a surface acoustic wave (SAW) device (110) or a quartz crystal microbalance (QCM) device (210), and a layer of metal organic framework (MOF) material (120,220) disposed on each of the at least one sensor device. The at least one sensor device is structured to sense a change in mass of the MOF material.

A gas sensor comprises a substrate, a first semiconductor-based sensor element for determining the density and/or viscosity of a gas, which element is arranged above the substrate and which has a resonant element, and a cover arranged above the first sensor element, wherein the substrate and/or the cover has an opening to allow the passage of a gas to the first sensor element.

A gas concentration measurement device comprises: a transmission circuit and a transmission oscillator for transmitting first ultrasonic waves in a concentration measurement space and transmitting second ultrasonic waves, which continue temporally from the first ultrasonic waves in the concentration measurement space; a reception oscillator and a reception circuit for receiving the ultrasonic waves that have propagated through the concentration measurement space; and a propagation time measurement unit for determining, on the basis of the times at which the first ultrasonic waves and the second ultrasonic waves were transmitted and the times at which the first ultrasonic waves and the second ultrasonic waves were received, the time in which ultrasonic waves propagate through the concentration measurement space. The second ultrasonic waves have an opposite phase with respect to that of the first ultrasonic waves, and the amplitude of the second ultrasonic waves is greater than that of the first ultrasonic waves.

A MEMS sensor includes a sensor package and a membrane arranged in the sensor package, wherein a first partial volume of the sensor package adjoins a first main side of the membrane and a second partial volume of the sensor package adjoins a second main side of the membrane, wherein the second main side is arranged opposite the first main side. The MEMS sensor includes a first opening in the sensor package, said first opening connecting the first partial volume to an external environment of the sensor package in an acoustically transparent fashion. The MEMS sensor includes a second opening in the sensor package, said second opening connecting the second partial volume to the external environment of the sensor package in an acoustically transparent fashion.