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UV reflectors

UV reflectors also reflect radiation energy in the visible and infrared (IR) energy spectral regions at least as efficiently as in the UV region. This is undesirable in such cases where the substrate or the piece being irradiated is heat sensitive. To overcome this, the surface of the reflector is coated with... [Pg.31]

Weather-Resistance. For long-lived outdoor products, most plastics can be stabilized somewhat by opaque UV reflectors or at least dissolved UV stabilizers. For inherent resistance to sunlight, rain, and other components of weather, some preferred plastics include acrylonitrile/styrene/acrylic rubber, acry-lonitrile/styrene/ethylene-propylene rubber, polyvinyl chloride, fluoropolymers, and polymethyl methacrylate. [Pg.653]

Another saturated tetrahydrofuryl core has found application as a component of liquid crystals. Cholesteric liquid crystal polymers are useful as photostable UV filters in cosmetic and pharmaceutical preparations for the protection of human epidermis and hair against UV radiation, especially in the range 280-450nm <2000DEP19848130>. Fused bifuran 81 is a suitable monomer for the preparation of these desired polymers as it contains the requisite characteristics of having more than one chiral, bifunctional subunit type which is capable of forming a cholesteric liquid crystal phase with a pitch of <450 nm. It also contains an achiral aromatic or cycloaliphatic hydroxyl or amino carboxylic acid subunit, achiral aromatic or cycloaliphatic dicarboxylic acids, and/or achiral aromatic or cycloaliphatic diols or diamines. Polymers prepared from suitable monomers, such as diol 81, can also be used as UV reflectors, UV stabilizers, and multilayer pigments. [Pg.584]

Neo-amylose is suited for food and non-food applications. Due to its resistant starch properties it is suited for use as dietary fiber [139]. Beside this food application, smooth spherical microparticles with a size of 10-100 pm are accessible by recrystaUization of Neo-amylose in dimethylsulfoxide (DMSO). These are suited as cosmetics additive in creams, lotions, or as UV-reflectors [140]. Furthermore, Neo-amylose has proved to be an advantageous constituent in hard or soft films in order to generate gelatin free capsules [139]. [Pg.18]

Details A white fine powdery solid, used in plastics and paints as a pigment of high refringence. It acts as a UV reflector, hence it can provide UV resistance. It is also a photocatalyst. [Pg.253]

Besides the application as dietary fibre, Neo-amylose can be used for the production of smooth particles with a size of 10-100 pm by re-crystallization in dimethyl sulfoxide (DMSO). The application of these particles as a supplement to cosmetics such as creams, lotions or as UV-reflector has been described in WO 0038623. " Further hard or soft films can be produced from Neo-amylose in order to generate gelatine-free capsules for encapsulation purposes. ... [Pg.289]

The most known photostabilizers can be classified by their action mechanisms UV reflectors, UV absorbers, quenchers of excited states, hydroperoxide decomposers, radical scavengers [22]. [Pg.170]

One way of implementing the UV disinfection process at existing activated sludge plants involves suspending the UV lights (in the form of low-pressure mercury arc UV lamps with associated reflectors) above the secondary clarifiers. The effluent is exposed to the UV radiation as it rises over the wire in a thin film. [Pg.455]

A typical UV curing unit may house one or more lamps. Most frequently, the material to be cured is passed underneath one or more lamps using a moving belt. The speed of the belt determines how long the web is exposed to the UV. The UV generated by the lamp is reflected by a reflector, which may either focus or defocus it, depending on the process. [Pg.21]

UV Irradiance is the radiant power arriving at a surface per unit area. The most commonly used unit of irradiance is W/cm. It varies with lamp output power, efficiency, the focus of its reflector system, and its distance to the surface. The intense peak of focused power directly under the lamp is referred to as peak irradiance. Although not a defined term, intensity is occasionally used to refer to irradiance. Irradiance... [Pg.21]

Infrared radiance is the amount of infrared energy primarily emitted by the quartz envelope of the UV source. This energy is collected and focused with the UV energy on the surface of the substrate to the extent depending on the IR reflectivity and efficiency of the reflector. Infrared radiafion can be expressed in exposure or irradiance units, but most commonly, the surface temperature it generates is of primary interest. The heat it produces may be a benefit or a nuisance. ... [Pg.22]

Example of a cold mirror reflector. (Courtesy of Horde UV America.)... [Pg.32]

Cold mirror A reflector that is coated by a dichroic material that absorbs or passes wavelengths in the infrared region while reflecting those in the UV range. [Pg.252]

Irradiator (lamp head) Assembly or fixture that is a sheet metal housing containing the UV bulb, reflector, shutter, magnetrons, or screens it may also include a blower. [Pg.256]

Instrument manufacturers offer a variety of devices, including monitoring systems for standard process or for spot curing technology and systems for process control. Online UV radiometers can measure and display the peak intensity and total UV energy used in the process. More-advanced systems map the entire process and evaluate the lamp focus, reflector focus and reflector efficiency within a specific... [Pg.183]

Figure 6. Instrumental schematic for vacuum UV photofragmentation-laser induced fluorescence measurement of ammonia SHGC, second harmonic generation crystal SFMC, sum frequency mixing crystal BS, beam splitter BD, beam dump TP, turning prism CL, cylindrical lens R, reflector TD, trigger diode OSC, oscillator cell AMP, amplifier cell BE, beam expander G, grating OC, output coupler M, mirror BC, beam combiner L, lens A, aperture PD, photodiode SC, sample cell RC, reference cell FP, filter pack SAM.PMT, sample cell photomultiplier REF.PMT, reference cell photomultiplier PP, additional photomultiplier port EX, exhaust and CGI, calibration gas inlet to flow line. (Reproduced with permission from reference 15. Copyright 1990 Optical Society of America.)... Figure 6. Instrumental schematic for vacuum UV photofragmentation-laser induced fluorescence measurement of ammonia SHGC, second harmonic generation crystal SFMC, sum frequency mixing crystal BS, beam splitter BD, beam dump TP, turning prism CL, cylindrical lens R, reflector TD, trigger diode OSC, oscillator cell AMP, amplifier cell BE, beam expander G, grating OC, output coupler M, mirror BC, beam combiner L, lens A, aperture PD, photodiode SC, sample cell RC, reference cell FP, filter pack SAM.PMT, sample cell photomultiplier REF.PMT, reference cell photomultiplier PP, additional photomultiplier port EX, exhaust and CGI, calibration gas inlet to flow line. (Reproduced with permission from reference 15. Copyright 1990 Optical Society of America.)...
Fig. 17.7. The MALDI schematic design of a MALDI ToF instrument (Micromass ToF Spec 2E, MMUK) showing ion generation via laser desorption (UV/IR), followed by ion acceleration through the field-free ToF-mass analyser, where the ions are reversed as they enter the reflector to end at the detectors. Fig. 17.7. The MALDI schematic design of a MALDI ToF instrument (Micromass ToF Spec 2E, MMUK) showing ion generation via laser desorption (UV/IR), followed by ion acceleration through the field-free ToF-mass analyser, where the ions are reversed as they enter the reflector to end at the detectors.
See other pages where UV reflectors is mentioned: [Pg.31]    [Pg.254]    [Pg.326]    [Pg.1351]    [Pg.31]    [Pg.254]    [Pg.326]    [Pg.1351]    [Pg.116]    [Pg.245]    [Pg.13]    [Pg.146]    [Pg.24]    [Pg.31]    [Pg.32]    [Pg.32]    [Pg.173]    [Pg.222]    [Pg.234]    [Pg.30]    [Pg.30]    [Pg.39]    [Pg.40]    [Pg.40]    [Pg.189]    [Pg.192]    [Pg.202]    [Pg.206]    [Pg.380]    [Pg.266]    [Pg.116]    [Pg.264]    [Pg.337]   


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