A universal respiratory detector for detecting a respiratory gas. The universal respiratory detector may include a plurality of layers with a visual indicator to quickly and reversibly change color to detect a respiratory gas parameter such as carbon dioxide. The color change may be visible from both sides of the detector. In some examples, the respiratory detector may be a biocompatible and conformable sticker for mounting on a person's face or an oxygen delivery device.

The present inventive concept relates to a battery-free gas sensor or humidity sensor comprising a metal-organic framework and a method of manufacturing the same. In a photodiode-type battery-free gas sensor or humidity sensor according to the present inventive concept, since photoelectron collection electrodes are formed at certain intervals between P-N junction layers, when gas is adsorbed thereon, the gas can be detected without an extra power source by change of photocurrent. Due to fine pores of the metal-organic framework, gas sensitivity may be increased and stability of catalysts may be improved. When catalysts are not provided, humidity may be detected. Therefore, a system that used the photodiode-type battery-free gas sensor and the photodiode-type battery-free humidity sensor together may be performed humidity correction to accurately measure an amount of a gas.

The present invention concerns an assay, a method and a device for detecting the presence of an odorous compound on a surface comprising enclosing the surface in a compartment, which compartment comprises an odor capturing agent including a visual indicating agent, wherein the surface comprises an odorous compound derived from biofilm.

The invention relates to a retroreflector able to be placed in contact with an environment, comprising, by way of constituent material, a material enabling a parameter of said environment to be picked up, said material modifying the optical transmission properties of the retroreflector when said parameter is present, said retroreflector being able to receive an incident light beam via a first face and to reemit a light beam via said first face.

A molecular detection apparatus of an embodiment includes: a first detector which includes a first sensor containing a MOF having a fluorescence emitting property, a light source which irradiates the MOF with light, and a light receiver which receives fluorescence from the MOF; a second detector which includes a sensor layer electrodes electrically connected with the sensor layer; and a type discrimination and concentration calculation part which discriminates a type of the molecules to be detected based on a measurement result measured by the first detector, and calculates a concentration of the molecules a measurement result measured by the second detector based on a discrimination result of a type of the molecules.

A heat cycle system is a heat cycle system (1) using a working medium containing hydrofluoroolefin (HFO) that has a double bond in a molecule structure, the heat cycle system (1) having a compressor (10), a high-pressure side heat exchanger (12), a low-pressure side heat exchanger (14), an expansion mechanism (13), and an acid detection means (40) which is disposed in a discharge pipe (21) connecting the compressor (10) and the high-pressure side heat exchanger (12) and which detects acid generated by decomposition of the working medium in a heat cycle.

Among other things, this application describes systems and methods for detecting gas using a wide band light source, and at least two narrow band light sensors, wherein each sensor may be operable to detect light at a different range of wavelengths. Additionally, the gas detector device may comprise a color changing indicator operable to react with gas in the air to change color, wherein different gases may react to create different colors, and wherein the sensors detect light reflected by the color changing indicator from the wide band light source. The gas detector device may comprise a processor in communication with the at least two light sensors operable to receive detected reflected wavelength information from the light sensors, and determine the type of gas that reacted with the color changing indicator based on the color detected by the sensors, wherein each color may be associated with a different type of gas.

The invention relates to a method for measuring the concentration of a gas component in an atmosphere of a packaging which is made from a plastic film and which comprises a gas concentration indicator substance on the side of the plastic film facing the atmosphere.

A device for detecting volatile compounds. The device includes a substrate and a matrix disposed on the substrate. The matrix includes a carboxyl-rich binder, a clay, and a pH-sensitive indicator dye admixed with the binder and the clay. The pH-sensitive indicator dye is dimensioned and configured to change color in response to contact with a pre-determined concentration of a volatile compound.

A method of immobilization of an insoluble dopant. In some embodiments, the insoluble dopant comprises a coordination polymer. In some embodiments, the insoluble dopant comprises a vapochromic coordination polymer. The method may comprise dissolving a polymer carrier in a solvent. The polymer carrier may comprise a thermoplastic such as, but not limited to, polylactic acid, polyethylene glycol or polycarbonate. The insoluble dopant (e.g. a coordination polymer such as a vapochromic coordination polymer) may then be mixed into the dissolved polymer. Phase separation of the mixture of the dopant and dissolved polymer may be induced to form a hydrogel. The hydrogel may be employed as is (e.g. as a raw material for hydrogel 3D printing, as a sensing material, etc.) or may undergo further processing (e.g. solidification, grinding, extrusion, etc.) before being employed, for example, as a raw material for 3D printing, as a sensing material, etc.