Mirrors concentrators

Methane reforming reaction is accomplished under the action of heat collected from mirror concentrator of solar light. The mixture of CO and H2 produced in this reaction can be stored and then, when necessary, converted into high-potential heat (with the temperature up to 950 K) in the methanation catalytic reactor. The efficiency of solar-to-chemical energy conversion as high as... 

Natural weathering (see Section 5.2.5) can be accelerated directly by exposure in a climate more severe than that expected in service. There are established test sites for this purpose in Australia and in the hotter states of the USA. The severity of exposure can also be maximised by arranging for the plane of the test pieces to automatically follow the sun. Another approach is to use a Fresnel mirror concentrating device that increases the intensity of sunlight falling on the test piece. These procedures are standardised in ISO 877 [25]. 

In one process, mirrors concentrate the Sun s rays on zinc oxide and vaporize it at a temperature of 1,200°C. The vaporized zinc is later recondensed into a powder. This zinc can then be transported, and when reacted with water vapor, produce hydrogen fuel while using the 02 from the water to recombine the zinc back into zinc oxide. 

As in tic, another method to vaUdate a chiral separation is to collect the individual peaks and subject them to some type of optical spectroscopy, such as, circular dichroism or optical rotary dispersion. Enantiomers have mirror image spectra (eg, the negative maxima for one enantiomer corresponds to the positive maxima for the other enantiomer). One problem with this approach is that the analytes are diluted in the mobile phase. Thus, the sample must be injected several times. The individual peaks must be collected and subsequently concentrated to obtain adequate concentrations for spectral analysis. 

These modes of operation ate used in conjunction with the two most popular energy analyzers, the cylindrical mirror analyzer (CMA) and the concentric hemispherical analyzer (CHA). The most common form of the CMA used today is the double-pass version diagramed in Eigute 21. This device consists of two perfectly coaxial cylinders of radii r and r. The outer cylinder is held at a potential of (— ) and the inner cylinder is held at ground. The... 

Solar-thermal technology uses tracking mirrors to concentrate sunlight onto a receiver. In turn, the receiver absorbs solar energy as heat, warming a fluid that then drives a turbine generator. Most solar-thermal plants requite cooling water. 

Fig. 3. The 10-MW Solar One plant, which advanced solar thermal power through the use of tracking mirrors to concentrate sunlight onto a central...

Nitric acid dissolves silver at all concentrations. This is the principal chemical reaction for the dissolution of silver into the soluble nitrate, which is the chemical intermediate for the production of electroplated ware, catalysts, battery plates, pharmaceuticals, mirrors, and silver haUdes for photographic materials. Nitric acid removes silver from the residual pellet in the gold fire assay. 

The cerium concentrate derived from bastnasite is an excellent polish base, and the oxide derived direcdy from the natural ratio rare-earth chloride, as long as the cerium oxide content is near or above 50 wt %, provides an adequate glass poHsh. The polishing activity of the latter is better than the Ce02 Ln0 ratio suggests. Materials prepared prior to any Ln purification steps are sources for the lowest cost poHshes available used to treat TV face plates, mirrors, and the like. For precision optical polishing the higher purity materials are preferred. 

The finish of flange facings varies with the manufacturer. For raised-face or male mating surfaces the finish usually consists of a continuous spiral groove formed by a round-nosed tool or a V tool (serrated finish). Female surfaces are smooth-finished (i.e., without definite tool markings). Other finishes are concentric-grooved, lapped, or mirror (cold-water). The latter two are usually for application without gaskets. 

A numerical solution of this equation for a constant surface concentration (infinite fluid volume) is given by Garg and Ruthven [Chem. Eng. ScL, 27, 417 (1972)]. The solution depends on the value of A. = n i — n )/ n — n ). Because of the effect of adsorbate concentration on the effective diffusivity, for large concentration steps adsorption is faster than desorption, while for small concentration steps, when D, can be taken to he essentially constant, adsorption and desorption curves are mirror images of each other as predicted by Eq. (16-96) see Ruthven, gen. refs., p. 175. 

Mirror segments (like Keck) will concentrate the diffracted energy into lines perpendicular to the edges, thus producing a diffraction pattern that is brighter or darker in some places than that of a circular aperture. 

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