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Optics summary

Many of the physical properties are not affected by the optical composition, with the important exception of the melting poiat of the crystalline acid, which is estimated to be 52.7—52.8°C for either optically pure isomer, whereas the reported melting poiat of the racemic mixture ranges from 17 to 33°C (6). The boiling poiat of anhydrous lactic acid has been reported by several authors it was primarily obtained duriag fractionation of lactic acid from its self-esterification product, the dimer lactoyUactic acid [26811-96-1]. The difference between the boiling poiats of racemic and optically active isomers of lactic acid is probably very small (6). The uv spectra of lactic acid and dilactide [95-96-5] which is the cycHc anhydride from two lactic acid molecules, as expected show no chromophores at wavelengths above 250 nm, and lactic acid and dilactide have extinction coefficients of 28 and 111 at 215 nm and 225 nm, respectively (9,10). The iafrared spectra of lactic acid and its derivatives have been extensively studied and a summary is available (6). [Pg.512]

In summary, laser-based fiber-optic telecommunications has had a revolutionary impact on long-distance telephone communication and is now expanding into many new appHcations areas. [Pg.17]

The optical absorption spectra of Pu ions in aqueous solution show sharp bands in the wavelength region 400—1100 nm (Fig. 4). The maxima of some of these bands can be used to determine the concentration of Pu ions in each oxidation state (III—VI), thus quantitative deterrninations of oxidation—reduction equiUbria and kinetics are possible. A comprehensive summary of kinetic data of oxidation—reduction reactions is available (101) as are the reduction kinetics of Pu + (aq) (84). [Pg.198]

Fig. 8. Summary of real and imaginary e2(tu) parts of the dielectric function for Cgo vacuum-sublimed solid films at room temperature over a wide frequency range, using a variety of experimental techniques. The arrow at the left axis points to i = 4.4, the observed low frequency value of ei obtained from optical data [81]. Fig. 8. Summary of real and imaginary e2(tu) parts of the dielectric function for Cgo vacuum-sublimed solid films at room temperature over a wide frequency range, using a variety of experimental techniques. The arrow at the left axis points to i = 4.4, the observed low frequency value of ei obtained from optical data [81].
The chapter is organized as follows in Section 8.2 a brief overview of ultrafast optical dynamics in polymers is given in Section 8.3 we present m-LPPP and give a summary of optical properties in Section 8.4 the laser source and the measuring techniques are described in Section 8.5 we discuss the fundamental photoexcitations of m-LPPP Section 8.6 is dedicated to radiative recombination under several excitation conditions and describes in some detail amplified spontaneous emission (ASE) Section 8.7 discusses the charge generation process and the photoexcitation dynamics in the presence of an external electric field conclusions are reported in the last section. [Pg.445]

Table 1. Summary of measurements of the parameters of VIRGO optics at LMA, compared with VIRGO specifications. Table 1. Summary of measurements of the parameters of VIRGO optics at LMA, compared with VIRGO specifications.
Hirschfeld, T. Deaton, T. Milanovich, F. Klainer, S. Fitzsimmons, C. Project Summary—Feasibility of Using Fiber Optics for Monitoring Groundwater Contaminants U.S. Environmental Protection Agency, Environmental Monitoring Systems Lab. Las Vegas, NV, January 1984. [Pg.241]

In summary, a new type of activation of a carboxyl group has been realized by incubation with a microorganism resulting in the formation of an optically active compound. This type of reactions is also expected to develop more in the future. [Pg.336]

In summary, we have briefly reviewed current research highlights from studies of second order nonlinear optical responses in organic and polymeric media. We have stressed how fundamental studies have led to microscopic understanding of important electronic states that comprise the origin of the large second order nonlinear responses in these... [Pg.22]

Summary. Coherent optical phonons are the lattice atoms vibrating in phase with each other over a macroscopic spatial region. With sub-10 fs laser pulses, one can impulsively excite the coherent phonons of a frequency up to 50THz, and detect them optically as a periodic modulation of electric susceptibility. The generation and relaxation processes depend critically on the coupling of the phonon mode to photoexcited electrons. Real-time observation of coherent phonons can thus offer crucial insight into the dynamic nature of the coupling, especially in extremely nonequilibrium conditions under intense photoexcitation. [Pg.23]

Table 5.1 Summary of results from Fig. 4, for gases in air at atmospheric pressure. Reprinted from Ref. 4 with permission. 2008 Optical Society of America... Table 5.1 Summary of results from Fig. 4, for gases in air at atmospheric pressure. Reprinted from Ref. 4 with permission. 2008 Optical Society of America...
In summary, the formation of optically active compounds through hydrolysis reactions is dominated by biocatalysis mainly due to the availability and ease of use of a wide variety of esterases, lipases and (to a lesser extent) acylases. Epoxide ring-opening (and related reactions) is likely to be dominated by salen-metal catalysts while enzyme-catalysed nitrile hydrolysis seems destined to remain under-exploited until nitrilases or nitrile hydratases become commercially available. [Pg.11]

In summary, the asymmetric hydrogenation of olefins or functionalized ketones catalysed by chiral transition metal complexes is one of the most practical methods for preparing optically active organic compounds. Ruthenium and rhodium-diphosphine complexes, using molecular hydrogen or hydrogen transfer, are the most common catalysts in this area. The hydrogenation of simple ketones has proved to be difficult with metallic catalysts. However,... [Pg.116]

We present here a condensed explanation and summary of the effects. A complete discussion can be found in a paper by Hellen and Axelrod(33) which directly calculates the amount of emission light gathered by a finite-aperture objective from a surface-proximal fluorophore under steady illumination. The effects referred to here are not quantum-chemical, that is, effects upon the orbitals or states of the fluorophore in the presence of any static fields associated with the surface. Rather, the effects are "classical-optical," that is, effects upon the electromagnetic field generated by a classical oscillating dipole in the presence of an interface between any media with dissimilar refractive indices. Of course, both types of effects may be present simultaneously in a given system. However, the quantum-chemical effects vary with the detailed chemistry of each system, whereas the classical-optical effects are more universal. Occasionally, a change in the emission properties of a fluorophore at a surface may be attributed to the former when in fact the latter are responsible. [Pg.299]

In summary, the optical and structural properties of PE and APE planar waveguides in LiNbOs and LiTaOs were studied. Raman spectroscopy was used to monitor the formation of various phases. [Pg.233]


See other pages where Optics summary is mentioned: [Pg.87]    [Pg.380]    [Pg.441]    [Pg.199]    [Pg.316]    [Pg.317]    [Pg.168]    [Pg.171]    [Pg.236]    [Pg.337]    [Pg.116]    [Pg.16]    [Pg.148]    [Pg.149]    [Pg.162]    [Pg.288]    [Pg.160]    [Pg.177]    [Pg.326]    [Pg.76]    [Pg.138]    [Pg.162]    [Pg.331]    [Pg.165]    [Pg.1]    [Pg.40]    [Pg.47]    [Pg.165]    [Pg.498]    [Pg.326]    [Pg.461]    [Pg.472]    [Pg.19]    [Pg.101]    [Pg.147]   
See also in sourсe #XX -- [ Pg.11 , Pg.16 ]




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