Ultraviolet sensitivity

For extensive studies of the effects of 254 nm radiation on acrylates and methacrylates, the reader is referred to the work of Morimoto and Suzuki(14) and of Grassie (15,16). In 1964, Oster reported on the crosslinking of these and other polymers by the near ultraviolet, sensitized by the presence of 2-methylanthraquinone (17). 

G Yu, K Pakpaz, and AJ Heeger, Semiconducting polymer diodes large size, low cost photodetectors with excellent visible-ultraviolet sensitivity, Appl. Phys. Lett., 64 3422-3424, 1994. 

Wu, K.J. Steding, A. Becker, C.H. Matrix-Assisted Laser Desorption-TOF-MS of Oligonucleotides Using 3-Hydroxy-picolinic Acid As an Ultraviolet-Sensitive Matrix. Rapid Commun. Mass Spectrom. 1993, 7,142-146. 

Mw of the PMMA portion, which is the more ultraviolet-sensitive of the two polymers. The PVdF portion also crosslinks, though at a slightly reduced rate compared with PVdF homopolymer alone. (The crosslinking is deduced from the fact that the PVdF fraction in the blend retains its solubility after longer exposure than does PVdF exposed alone.)... 

FLUORESCENCE AND ULTRAVIOLET SENSITIVITIES OF SUBSTITUTED AROMATIC ACIDS... 

This is the mechanism proposed in the model for the transduction of visual spectrum photons by the eye. It has led to a very accurate equation for the perceived spectral response of all eyes in the animal world, including the ultraviolet sensitivity of many animals. This is particularly true for the well-documented sensitivity of (many) insects. 

During the 1950-60 time period, there was speculation that the ultraviolet sensitivity of animals was due to a secondary absorption band of retinol and retinal designated the p-band. More recent data does not show a good correlation between the peak spectral absorption in the UV band and the peak absorption for these two p-bands. In Section 17.3.3, the absorption in the lens due to these two p-bands is seen to occupy a distinctly different spectral region than that of the UV chromophoie in humans. If the absorption in the U V was due th the presence of these bands in the chromophores of the S-, M- or L-band photoreceptors, the measured sensitivity in the UV band should correlate with the measured sensitivity in at least one of these other bands. Multiple authors have performed these experiments. They have noted the lack of correlation between the UV sensitivity of their subjects and the state of adaptation of the subjects other spectral bands165. 

The fact that there are four saline-based chromophores and the experimental evidence that they appear in at least two distinct but overlapping sets of three should be important in inferring the actual relationship between the genes and the chromophores. Comparing the genetic code for the common chromophores between the ultraviolet sensitive members of Arthropoda who are believed to lack a L-channel chromophore and the members of Mollusca and Chordata who do exhibit L-channel sensitivity should prove beneficial. Since most members of Chordata are known to be tetrachromatic, focusing on the presence or absence of the ultraviolet chromophore may not be as fruitful. Recent data has confirmed that the system architecture of the human system is tetrachromatic. Our vision in the ultraviolet is limited primarily by the absorption of our lens group. 

Morton, A.R. and Haynes, R.H. (1969) Changes in the ultraviolet sensitivity of Escherichia coli during growth in bath cultures. J. Bacteriol. 97, 1379-1385. 

Fig 1 Scheme of the screen-printed process a typical thick-film screen consists of a finely woven mesh of stainless steel, nylon or polyester, mounted under tension on a metal frame, normally aluminium. The screen defines the pattern of the printed film and also determines the amount of paste which is deposited. The mesh is coated with a ultraviolet sensitive emulsion (usually a polyvinyl acetate or polyvinyl alcohol sensitized with a dichromate solution) onto which the circuit pattern can be formed photographically. The ink is placed at one side of the screen and a squeegee crosses the screen under pressure, thereby bringing it into contact with the substrate and also forcing the ink through the open areas of the mesh. The required circuit pattern is thus left on the substrate... 

Previous syntheses of tricarbonyl( /-diene)iron complexes have relied mainly on the reaction of Fe(CO)s, Fc3(CO)i2, or Fc2(CO)9 with the free diene. The use of the first two carbonyls suffers from the prolonged reflux times and/or ultraviolet irradiation necessary to obtain reaction and the consequent low yields and mixtures of complexes obtained with heat- and ultraviolet-sensitive dienes. The latter reagent, although utilized at lower temperatures, may react with polyenes (n > 3) to give mixtures containing, in addition to the expected product, binuclear derivatives containing a metal—metal bond.2... 

Robinson, G. W., Caughey, T. A., Auerbach, R. A. Picosecond emission spectroscopy with an ultraviolet sensitive streak camera. In Advances in Laser Chemistry/Springer Series in Chemical Physics. Tlewafl, A. H. (Ed.) p. 108, Berlin, Heidelberg, New York Springer 1978 Robinson, G. W. et al. J. MoL Struct 47, 221 (1978)... 

Several copper(I) and copper(II) complexes form nuclei for the catalytic deposition of copper or nickel. These include phosphite complexes of Cu such as CuP(OMe)3BH3CN or [Cu(P(OMe)3)4]BPli4 and Cu amine complexes such as [Cu(en)2][BPli4]2 or [Cu(bipy)2][BPli4]2. The complexes are only ultraviolet sensitive, permitting their being handled in dayli t. They are considered useful in printed circuit manufacturing. 

I. No vales Flamarique (2000). The ontogeny of ultraviolet sensitivity, cone disappearance and regeneration in the sockeye salmon Oncorhynchus nerka. J. Exp. Biol, 203, 1161-1172. 

L.A. Wilkens (1984). Ultraviolet sensitivity in hyperpolarizing photoreceptors of the giant clam Tridacna. Nature, 309,446-448. 

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