Light direction

Fodor, S. P. (1991). Light-directed, spatially addressable parallel chemical synthesis. Science 251, 767-773. 

The action spectmm of positive and negative phototaxis of Anabaena variabilis was measured recently106). This species contains no C-phycoerythrin. Accordingly, maximum activity is found at around 615 nm (Fig. 7). In addition, in this form a second maximum occurs at around 675 nm, and a third small, but distinct, one at 440 nm, both indicating that chlorophyll a is also involved in the active light absorption (see above). The utilization via photosynthesis, however, could be excluded in this case, since the trichomes oriented themselves perfectly well to the light direction in the presence of photosynthetic inhibitors, such as DCMU and DBMIB, at concentrations in which the photosynthetic oxygen evolution was almost completely inhibited. 

In-situ Light-Directed Synthesis of Oligonucleotides for High Density Arrays... 

In-situ photofabrication of OND arrays involves light-directed, spatially addressable, parallel (combinatorial) chemical synthesis [35,43,66-68]. A surface, usually a sihcon wafer or a glass slide, is coated with hnker molecules... 

Selenium has many industrial uses, particularly electronic and solid-state applications, which have increased phenomenally in recent years. This is attributed to its unique properties (1) it converts light directly to electricity (photovoltaic action) (2) its electrical resistance decreases with increased illumination (photoconductivity) and (3) it is able to convert alternating current to direct current. 

Using the published absorption coefficients (cr) as a function of wavelength, one can then apply the Beer-Lambert law to calculate the intensity of light transmitted through such a vertical column to the earth s surface or to an altitude z. The resulting attenuation coefficients for 03 are shown in Fig. 3.15 for an overhead sun. Clearly, 03 is responsible for most of the attenuation of light directly from the sun of A < 310 nm reaching the earth s surface. 

Optical Tweezers, Light-Directed Synthesis, and Imaging... 

Light-directed solid state synthesis of peptides217 and oligonucleotides is another new tool.218 Development of this technology may provide new advances in preparation of DNA chips (Chapter 26) with a higher density of components than are now available. 

I-odor. S P A. 01 at. "Light-Directed. Spatially Addressable Parallel Chemical Synthesis.". Vcienee, 767 (February IS. 19911 Jam>ld. M.F. "Nanosurfaee Clietnisiry on Size-Selected Silicon C liniers." Seitner. 1085 tMay 14. 1991). 

Rowland was the first to rule reflection gratings on concave metal surfaces. Such gratings eliminate the necessity of the spectroscope collimator or focusing lenses, as they take light direct front the spectroscope slit and form the spectral-line images like a concave mirror. The echelon is another special type of grating. 

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