摘要:
Sensor array for detecting biomarkers for cancer in breath samples. The sensor array is based on 2D films or 3D assemblies of conductive nanoparticles capped with an organic coating wherein the nanoparticles are characterized by a narrow size distribution. Methods of use of the sensor array for discriminating between patterns of volatile organic compounds from healthy individuals and patients with various types of cancer are disclosed.
摘要:
The measurement is conducted by means of thermogravimetric scales (10) bearing at one end of the beam (20) a catalyst body (30) for catalysing a coking reaction of the tars present in the gas state. Precautions are taken in order to ensure homogeneity and regularity of the sampled gas flow and to guarantee predominant catalysis on the catalytic body (30), the weight increase of which gives the weight of the deposited coke and indirectly the content of tars present in the gas state in the gas to be measured. A calorimetric device (34) for analyzing gases from the coking of the tars provides a complementary and/or additional measurement. The solid tars are filtered beforehand, but their content may be measured by an auxiliary device.Possible application to analyzing gases from biomass.
摘要:
A chemical sensor using metal nano-particles and a method for manufacturing a chemical sensor using metal nano-particles are provided. The chemical sensor includes: metal nano-particles; single-ligand organic molecules (or a single molecule) that binds to the metal nano-particles by using a metal bonding functional group; a substrate bonding functional group formed at the metal nano-particles and the single-ligand organic molecules as bound to each other; a substrate; electrodes formed on the substrate and having an interdigitate (IDT) structure; and a substrate functional group formed on the substrate and positioned between the electrodes, wherein the substrate bonding functional group and the substrate functional group are covalently bonded.
摘要:
A thin-film passive sampler for use in detecting hydrophobic organic contaminants in air or aqueous environments. The sampler features a relatively thin layer of a suitable absorbent matrix coated directly on a solid support unit made of an inert material such as titanium or glass fibers. The passive samplers are simple and cost-effective to manufacture, easy to use, and exhibit rapid equilibration times and high accuracy.
摘要:
A gas-sensing semiconductor device 1′ is fabricated on a silicon substrate 2′ having a thin silicon dioxide insulating layer 3′ in which a resistive heater 6 made of doped single crystal silicon formed simultaneously with source and drain regions of CMOS circuitry is embedded. The device 1′ includes a sensing area provided with a gas-sensitive layer 9′ separated from the heater 6′ by an insulating layer 4′. As one of the final fabrication steps, the substrate 2′ is back-etched so as to form a thin membrane in the sensing area. The heater 6′ has a generally circular-shaped structure surrounding a heat spreading plate 16′, and consists of two sets 20′, 21′ of meandering resistors having arcuate portions nested within one another and interconnected in labyrinthine form. The fabrication of the heater at the same time as the source and drain regions of CMOS circuitry is particularly advantageous in that the gas-sensing semiconductor device is produced without requiring any fabrication steps in addition to those already employed in the IC processing apart from a post-CMOS back etch and deposition of the gas-sensitive layer. The circular design is advantageous in that it is the best solution to minimise the size of the membrane at fixed power loss and heated area.
摘要:
A chemical vapor sensor is provided that passively measures a suspect chemical species of interest with high sensitivity and chemical specificity, for use with safety systems. A vapor concentrator amplifies a suspect chemical vapor concentration to a detectible level, for use with an infrared detector. Compensation is provided for environmental variations that may influence the passive measurement of the chemical vapor sensor. Environmental variations may include extrinsic vapors in the surrounding air, or air currents that divert the sample vapor as it drifts from the suspect vapor source to a sampling intake. In an example, ethanol vapor is measured and carbon dioxide tracer measurements are used to calculate an ethanol vapor measurement that is adjusted for environmental variations. In an aspect, a time artifact filter sets the output of the carbon dioxide sensor to match the time dependence of the ethanol sensor, to calculate blood alcohol concentration.
摘要:
A method for detecting a gas phase constituent such as carbon monoxide, nitrogen dioxide, hydrogen, or hydrocarbons in a gas comprising oxygen such as air, includes providing a sensing material or film having a metal embedded in a catalytically active matrix such as gold embedded in a yttria stabilized zirconia (YSZ) matrix. The method may include annealing the sensing material at about 900° C., exposing the sensing material and gas to a temperature above 400° C., projecting light onto the sensing material, and detecting a change in the absorption spectrum of the sensing material due to the exposure of the sensing material to the gas in air at the temperature which causes a chemical reaction in the sensing material compared to the absorption spectrum of the sensing material in the absence of the gas. Systems employing such a method are also disclosed.
摘要:
A gas-sensing semiconductor device 1′ is fabricated on a silicon substrate 2′ having a thin silicon dioxide insulating layer 3′ in which a resistive heater 6 made of doped single crystal silicon formed simultaneously with source and drain regions of CMOS circuitry is embedded. The device 1′ includes a sensing area provided with a gas-sensitive layer 9′ separated from the heater 6′ by an insulating layer 4′. As one of the final fabrication steps, the substrate 2′ is back-etched so as to form a thin membrane in the sensing area. The heater 6′ has a generally circular-shaped structure surrounding a heat spreading plate 16′, and consists of two sets 20′, 21′ of meandering resistors having arcuate portions nested within one another and interconnected in labyrinthine form. The fabrication of the heater at the same time as the source and drain regions of CMOS circuitry is particularly advantageous in that the gas-sensing semiconductor device is produced without requiring any fabrication steps in addition to those already employed in the IC processing apart from a post-CMOS back etch and deposition of the gas-sensitive layer. The circular design is advantageous in that it is the best solution to minimise the size of the membrane at fixed power loss and heated area.
摘要:
The chemical compound: Each R1 is H or CH3. A device for detecting an analyte having: a substrate; a film on the substrate, a flow cell for delivering air containing the analyte to the film, and an apparatus for measuring the refractive index of the film. Each R2 is an alkyl group. Each X is O or S.
摘要:
A gas sensor unit includes a conductive polymer and an absorbent for absorbing gas molecules. The conductive polymer is polyaniline (PAN) and the absorbent is polyurethane (PU). The content of the conductive polymer is 25-55 wt % and the content of the absorbent is 45-75 wt %