A nephelometric turbidimeter for measuring a turbidity of a liquid sample in a transparent sample cuvette. The nephelometric turbidimeter includes a cuvette chamber housing with a cuvette chamber having the transparent sample cuvette arranged therein, and a drying apparatus. The drying apparatus includes a cuvette chamber inlet opening which vents the cuvette chamber, a cuvette chamber outlet opening which de-vents the cuvette chamber, an air circulator which circulates air from the cuvette chamber outlet opening to the cuvette chamber inlet opening, and a drying body. The drying body is provided as a container of a hygroscopic agent defined by a drying substance which is arranged in a drying path between the cuvette chamber outlet opening and the cuvette chamber inlet opening so that air flows through the drying body.

A probe for an IR or UV sensor comprising a light emitter and detector is described comprising a lens. The detector detects the spectrums of the emitted light after it has passed a gas to be measured. The sensor of the present invention is especially suitable for such as harsh or aggressive environments measuring the exhaust gasses, for example in ships, vehicles, chimneys etc., and comprises purge gas protections for delicate optical parts to prevent particles etc. from the exhaust gas depositing on the optics. The sensor further has a flow of sample gas from the gas to be measured being adapted to prevent the purge gas from inferring with the measurements.

A surface analysis system for an air purification unit includes an air purification unit including a carrier and a metallic catalyst supported on the carrier, the air purification unit is configured to provide an air flow path in a first direction, a first light-source unit configured to irradiate inspection light onto a surface of the air purification unit, and an analysis unit configured to determine information regarding the surface of the air purification unit by receiving the inspection light reflected by the surface of the air purification unit, wherein the inspection light has an infrared wavelength, and the analysis unit is further configured to obtain oxidation number information of the metallic catalyst through infrared spectroscopy.

In order to provide a more practical gas analysis device than that having conventionally been, while keeping the laser source and the photodetector separated from the gas cell, thereby preventing exposure to a high temperature, the gas analysis device includes: a gas cell; a laser source or a photodetector separated from the gas cell; and a laser light transmission mechanism provided between the gas cell and the laser source or the photodetector. The laser light transmission mechanism includes one or a plurality of tubular members, and an inner space of the one or the plurality of tubular members provides a light path for the laser light.

Methods and systems for inspecting a specimen are provided. One system includes an inspection subsystem configured for directing light to an area on the specimen and for generating output responsive to light from the area on the specimen. The system also includes a first gas flow subsystem configured for replacing a gas in a first local volume surrounding the area on the specimen with a first medium that scatters less of the light than the gas. In addition, the system includes a second gas flow subsystem configured for replacing the gas in a second local volume proximate the first local volume with a second medium different than the first medium. The system further includes a computer subsystem configured for detecting abnormalities on the specimen based on the output.