Mirrors glazings

Polymers have many potential applications In solar technologies that can help achieve total system cost-effectiveness. For this potential to be realized, three major parameters must be optimized cost, performance, and durability. Optimization must be achieved despite operational stresses, some of which are unique to solar technologies. This paper Identifies performance of optical elements as critical to solar system performance and summarizes the status of several optical elements flat-plate collector glazings, mirror glazings, dome enclosures, photovoltaic encapsulation, luminescent solar concentrators, and Fresnel lenses. Research and development efforts are needed to realize the full potential of polymers to reduce life-cycle solar energy conversion costs. 

Industrial Applications Electrochemichromic solutions/devices (mirrors, glazings, partitions, filters, displays, lenses) oxygen-barrier packaging materials oxidation-reduction (redox) indicator " " ... 

The main application areas for electrochromic systems are in electrically switchable rear-view car mirrors for anti-dazzle, in glazing units for temperature and light control and in visnal displays. The main advantage offered by electrochromic systems in the first two of these applications is the fact that the cells can be made very large, i.e. one cell can comprise a whole glazing unit. 

The desirable properties of an electrochromic system for use in both rear-view mirrors or glazing units are ... 

Focusing collectors are usually cast acrylic Fresnel lenses, or mirrors of aluminized polyester film in frames of aluminum. These reflectors are either enclosed in a bubble of poly(vinyl fluoride) film, or under polycarbonate glazing, which may be covered with a fluorocarbon film to reduce the reflectivity. The absorbers for active systems are copper or aluminum since the temperatures are too high (325—370°C) for plastics. The frames, however, can be molded ABS, high density polyethylene or polyurethane, either solid or structural foam. Polybutylene or chlorinated PVC can be used for piping hot water, and tanks can be made of either reinforced polyester or blow- or rotational-molded, high density polyethylene (12—15). 

Many grades of intedayer are produced to meet specific length, width, adhesion, stiffness, surface roughness, color (93,94), and other requirements of the laminator and end use. Sheet can be supplied with vinyl alcohol content from 15 to about 23 wt %, depending on the supplier and application. A common intedayer thickness for automobile windshields is 0.76 mm, but intedayer used for architectural or aircraft glazing applications, for example, may be much thinner or thicker. There are also special grades to bond rear-view mirrors to windshields (95,96) and to adhere the components of solar cells (97,98). Multilayer coextruded sheet, each component of which provides a separate property not possible in monolithic sheet, can also be made (99—101). 

It also is formed by reduction of soluble arsenic compounds by zinc in acidic solution. This reaction is the basis of an important and sensitive test for arsenic, the Marsh test (Fig. 21-5). The arsenic is deposited as a steel-gray or black mirror from the burning gas onto a cold glazed porcelain dish held in the flame. Antimony produces a velvety brown or black deposit, which is not soluble in sodium hypochlorite solution, whereas the arsenic deposit is. The antimony deposit, but not that of... 

Polymeric materials are used In all solar technologies. In addition to such conventional applications as adhesives, coatings, moisture barriers, electrical and thermal Insulation, and structural members, polymers are used as optical components In solar systems. Mirrors on parabolic troughs are made up of metallized fluoropolymers and acrylics. Commercial flat-plate collectors are glazed with fluoropolymers and ultraviolet-stabilized polyester/ glass fiber composites. Photovoltaic (PV) cell arrays are encap-... 

Local Irregularities (slope-error) in the shape of reflectors present a problem with polymer-glazed mirrors. A slope-error tolerance as low as one mllllradlan Is needed for some point-focus concentrators [14]. This tolerance has been met with glass mirrors however, metallized polymeric films have a poorer tolerance. 

The production of large-area EC-devices have been proposed for architectural, automotive and aerospace glazing, for the realization of automotive sunroofs, rear-view EC-mirrors and for EC-displays (Lampert, 1999). Further applications are EC-paper, EC-glasses, cathodic ray tubes (de Vries, 1999). An overview of the applications of EC-devices and the companies working on it is given by Lampert et al. (2003). The requirements are highly dependent on their use. 

Applications include transparent cookware (Visions , thermal expansion = 7 x 10 V°C), optical materials (e.g., ring-laser gyroscopes), telescope mirror blanks (Zerodur ), infrared-transmitting electric range tops, wood-stove windows, fire door glazing... 

In addition to the extensive use of tin metal itself and its alloys, various compounds of tin are used in industry and commerce. Tin(IV) oxide is used as an opacifier for vitreous enamels, in ceramic glazes and as a polishing powder. Tin chlorides are used to weigl t natural silk, stabilize soap perfumes, silver glass mirrors and as chemical reducing agents. Tin(II) fluoride finds extensive use as an additive to dentifrices. ... 

A metal is characterized by free electrons so that coq is zero and n is complex. In fact metals are not transparent but reflect light, and this is used in mirrors and low-E glazing ... 

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