摘要:
The invention relates to a device for monitoring the oxygen concentration in an aircraft tank. The device includes an absorption measuring section equipped with a laser or laser diode (6), a photodiode (7), a temperature sensor (8) and a reflector (5) for carrying out laser spectroscopy on a gas volume to be measured inside the tank. The conducting components of the device are positioned outside the tank and its reflector (5) is positioned in the tank in the gas volume to be measured, the components and reflector being optically coupled by a window (3) that is situated in the tank wall (2). The absorption measuring section is mainly located in the chamber containing the gas to be measured.
摘要:
The invention relates to a device for monitoring the oxygen concentration in an aircraft tank. The device includes an absorption measuring section equipped with a laser or laser diode (6), a photodiode (7), a temperature sensor (8) and a reflector (5) for carrying out laser spectroscopy on a gas volume to be measured inside the tank. The conducting components of the device are positioned outside the tank and its reflector (5) is positioned in the tank in the gas volume to be measured, the components and reflector being optically coupled by a window (3) that is situated in the tank wall (2). The absorption measuring section is mainly located in the chamber containing the gas to be measured.
摘要:
A method an apparatus uses the narrow-band measurement of the absorption of given spectral lines of a gas using laser light sources, so that the spectrally resolved measurement of individual absorption lines, and thus the selection of an individual gas component, is possible. A laser diode which is operated at a higher temperature is correspondingly varied over a certain temperature region, wherein the selected spectral line is crossed. On the basis of absorption measurements, the method and sensor deliver the gas concentration, with a high selectivity.
摘要:
A FET gas sensor having a relatively low operating temperature, for example, room temperature, is free from cross sensitivities from interfering gases by a preceding in-line filter. The sensor's service life is substantially stabilizable by using fabric-like activated charcoal filters which can be regenerated by a moderate temperature increase, and by limiting the diffusion of the analyte gas, which is made possible by the relatively small amount of gas detectable on the sensitive layer of the sensor. This substantially increases the service life of the filters. The gas sensor eliminates cross sensitivities to thereby increase the detection reliability thereof. Also, the gas sensor has relative long term stability and is economical to build. The gas sensor can read relatively weak signals generated by gas-sensitive layers, for example, without other stronger gas signals interfering with the weak signals.
摘要:
A gas sensitive field effect transistor comprises a semiconductor substrate that includes a capacitance well, and source and drain regions of a field effect transistor. A gate of the field effect transistor is separated from the semiconductor substrate by an insulator, and a gas sensitive layer separated from the gate by an air gap. The field effect transistor provides an output signal indicative of the presence of a target gas within the air gap to an amplifier, which provides an amplified output signal that is electrically coupled to the capacitance well.
摘要:
The invention relates to a gas sensor which is used to detect ammonia by detecting and evaluating conductivity variations on semi-conductive metal oxides, comprising: a substrate, a gas sensitive layer made of a semi-conductive metal oxide, a catalytic filter which is disposed in front of the metal oxide, said filter being used to convert ammonia, contained in the measuring gas, into a NO/NO2 mixture or to only NO2, measuring electrodes which are arranged on the surface of the substrate in order to detect conductivity variations in the semi-conductive metal oxide which is at least sensitive to NO/NO2, a controllable electric heating device which is used to adjust predetermined temperatures at least for the semi-conductive metal oxide, whereby the formed NO/NO2 can be guided to the metal oxide and the content of ammonia in the measuring gas can be determined from the NO/NO2-measurement by means of the semi-conductive metal oxide.
摘要翻译:本发明涉及一种用于通过检测和评估半导电金属氧化物的导电率变化来检测氨的气体传感器,包括:基板,由半导体金属氧化物制成的气敏层,设置在催化过滤器 在金属氧化物的前面,所述过滤器用于将包含在测量气体中的氨转化为NO / NO 2混合物或仅将NO2测量电极设置在衬底的表面上,以便检测电导率变化 至少对NO / NO2敏感的半导体金属氧化物,至少用于半导体金属氧化物调节预定温度的可控电加热装置,由此所形成的NO / NO 2可被引导到金属 氧化物,测定气体中的氨的含量可以通过半导体金属氧化物从NO / NO 2测定中求出。
摘要:
A gas-sensitive field-effect transistor (GasFET) for the detection or measurement of an amount of hydrogen sulfide present in ambient air includes a raised gate electrode and a transistor structure. The raised gate electrode may be formed from or coated with a gas-sensitive material such as tin oxide, or silver, silver oxide or mixtures thereof. An insulator layer may be disposed on top of the transistor structure. An air gap is formed between the gas-sensitive layer of the raised gate electrode and the insulator layer on top of the transistor structure.
摘要:
An ozone sensor has an ozone-sensitive layer containing an ozone-sensitive material which is encapsulated in a polymer or in a polymer mixture or is coated by at least one polymer or polymer mixture. Advantages result from a longer service life of the ozone-sensitive materials which, because of their high hygroscopic properties, would not be stable without encapsulation or coating. Furthermore, a polymer matrix can be selectively used as a filter or in order to eliminate interfering influences.
摘要:
A volumetric flow of an analyte, including exhaled air, is fed to a gas sensor unit by used of gas flow device, which can include various sensors for the determination of nitrogen oxides. An oxidation catalyst is used when using an NO2 sensor, which converts nitrogen monoxide to nitrogen dioxide and the gas sensor unit measures the content of nitrogen dioxide. The nitrogen monoxide content is calculated from the nitrogen dioxide content. In order to eliminate cross-sensitivity moisture and ethanol are also measured. The device can be applied to the determination of nitrogen monoxide content of exhaled air.
摘要:
A biosensor for detecting an antigen using an antigen/antibody coupling includes: a silicon substrate, at least one interdigital electrode pair structure that is located on the silicon substrate, the electrode pair being interspaced at a maximum distance of 1.0 μm; a counter-electrode on the silicon substrate; a reference electrode; a first layer of protein, covering at least the interdigital electrode structure; a selective second protein layer applied to the first layer and containing a capture antibody selected specifically with respect to the antigen of interest and to which the antigen can be coupled. A sensor signal can be read on the interdigital electrode structure, if the antigen is coupled to the capture antibody by way of a sample to be analysed that comes into contact with the biosensor and a redox reactive molecule is enzymatically released on the sensor surface by an enzyme-marked detection antibody likewise coupled to the antigen.