Ultraviolet radiation sensor

In Chapter 5.4, optical ultraviolet radiation sensors are described, including UV-enhanced silicon-based pn diodes, detectors made from other wide band gap materials in crystalline or polycrystalline form, the latter being a new, less costly alternative. Other domestic applications are personal UV exposure dosimetry, surveillance of sun beds, flame scanning in gas and oil burners, fire alarm monitors and water sterilization equipment surveillance. 

Saura, I (1994), Gas-sensing properties of SnOj pyrolytic films subjected to ultraviolet radiation Sensors and Actuators B Chemical, 17,3,211-14. 

The detector best suited to meet these conditions is a radiation type sensor. Ultraviolet (UV), infrared and visible radiation are generated when combustion produces a flame and all three types of radiation sensors respond to the radiation from the flame. 

Rosen, R. Davidov, L. A. Rossa, R. A. Belkin, S. Microbial sensors of ultraviolet radiation based on rec, lux gene fusion, Appl Biochem. BiotechnoL, Nov-Dec. 2000, 89(2-3), 151-160. 

Rapid and sensitive colorimetric sensor for the detection of Hg using L-cysteine-functionalized GNPs induced by ultraviolet radiation The L-cysteine-modified GNPs aggregate quickly in the presence of Hg. Functionalized GNPs can be used for delivery of various payloads into cells, such as small drug molecules or laige biomolecules like DNA and siRNA Chai et al. [61]... 

In the most common method, the solution is irradiated with near-ultraviolet radiation (200-400 nm) to decompose organic matter by means of a radical formation mechanism. Then the generated CO2 is transported toward the detector with a carrier gas. In order to eliminate some ionic compounds that can interfere with the measurement, a membrane is placed before the detector. The detection is carried out either by the measurement of conductivity via a sensor or by a nondispersive infrared analyzer. In this online system, the sample analysis takes aroimd 6 min. Other systems based on the same principle have also been described. In this case the oxidation and detection are produced in the same chamber. In this "batch" apparatus the sample is trapped and analyzed for 3-30 min. With this latter system, some ionic species other than H and HCO3 can interfere with the conductivity readings. Species such as Ti02 [85,90] and persulfate [91,121] have been used as catalysts present as a diluted suspension in water. The TOC is obtained from the difference between the conductivities for the irradiated and nonirradiated samples. 

Luminescence can be defined as the emission of light (intended in the broader sense of ultraviolet, visible, or near infrared radiation) by electronic excited states of atoms or molecules. Luminescence is an important phenomenon from a basic viewpoint (e.g., for monitoring excited state behavior) [1] as well as for applications (lasers, displays, sensors, etc.) [2,3]. 

Irradiation Measurements. An Epply photometer with sensors for total global irradiance, photosynthetic active radiation (PAR), and ultraviolet (UV) radiation (295-385 nm) was used to measure irradiance continuously and averaged a measurement every 0.5 h. 

There are a variety of ultraviolet detection devices. They convert radiation arriving at a sensing device or medium to some form of display. Conversion methods include electrical (photovoltaic cells and phototubes), thermal (thermopile), and chemical (photographic plates). For most devices, selective filters determine what wavelengths arrive at the sensor. 

While heat may indicate that a fire is in progress, often monitoring this one parameter is not sufficient to insure fire safety, since localized fires may not excite the heat sensor. Instrumentation is available to monitor the cylinder cabinet for smoke, ultraviolet, or infrared radiation. Use of multiple types of fire detectors provides the most protection in all types of situations. 

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