Wavelength shift

Pressure. Standard atmospheric pressure is defined to be the force exerted by a column of mercury 760-mm high at 0°C. This corresponds to 0.101325 MPa (14.695 psi). Reference or fixed points for pressure caUbration exist and are analogous to the temperature standards cited (23). These points are based on phase changes or resistance jumps in selected materials. For the highest pressures, the most rehable technique is the correlation of the wavelength shift, /SX with pressure of the mby, R, fluorescence line and is determined by simultaneous specific volume measurements on cubic metals... 

Isothiazole has an absorption maximum in ethanol solution at 244 nm, with a molar absorptivity of 5200. This absorption occurs at a longer wavelength than with pyrazole or isoxazole, the displacement being due to the presence of the sulfur atom. A series of approximate additive wavelength shifts has been drawn up in Table 11 and this should enable prediction of UV maxima of isothiazoles with reasonable accuracy, even for multiply substituted compounds. The longest wavelength band results from a electronic... 

P.D. Horn and Y.M. Gupta, Wavelength Shift of the Ruby Luminescence R Lines Under Shock Compression, Appl. Phys. Lett. 49, 856-858 (1986). 

Systematic studies on disubstituted thiophenes are scarce, but some differences between the various series of disubstituted thiophenes have been detected. According to Imoto et al., the main effect of substituents in 2,5-disubstitution in thiophenes appears in the wavelength shift, whereas the main effect of substituents in the 2,4-disub-stituted thiophenes appears in the intensity changes of the bands. The intensities of the first absorption band of some 2,6-disubstituted thiophenes have been calculated from the spectroscopic momenta of the substituents. The UV absorption of thiophene was displaced... 

Figure 1-19, which contains some of the results obtained by Faessler and Goehring,41 shows what information about chemical constitution the x-ray emission process can yield under favorable circumstances. In this simple case, wavelength shift and line intensity are both useful, the latter in the less obvious way explained below. 

Absorption edges, table, 307, 308 wavelength shift with change of chemical state, 37, 38... 

Wavelength shift of K absorption edge of sulfur, 37, 38 Weight-fraction , use, 164, 171 Window absorption, 45 Windowless counter tube, 55, 222 Windows, for electron beam, 177 for proportional counter, 55... 

Substituent effects on the are remarkable. Electron-withdrawing groups at the 5 -position, e.g., 5 -nitro-substitution (indoline component), and donor substituent at the 8-position (benzothiopyran component) in 44 leads to a longer wavelength shift. As the polarity of the solvent increases, the max of the colored form of spiroindolinobenzothiopyran results in hypsochromic shift. This can be interpreted as the existence of a polar structural component of the colored form in the ground state. Kinetic study has suggested that the zwitterionic structure largely contributes to the colored form of 6-nitrospiroindolinobenzothiopyran, as well as spiropy-rans.97 Based on H-NMR and X-ray analysis,98 99 the existence of an... 

Purely electrochromic dyes. Transient membrane potentials have typical amplitudes on the order of 100 mV across a typical 4 nm thick bilayer. This means an average electric field within the membrane of 2.5 x 107 Vm 1 or 2.5 x 105 V cm While this may seem like a very large field, in fact it produces a small wavelength shift of only about 0.4 nm (20 cm-1) in A,max for typical dyes absorbing... 

The assignment of the band to Cr(CO)5 is not conclusive. Direct comparison with visible absorption bands of matrix-isolated Cr(CO)5 is difficult because of wavelength shifts produced by Cr(CO)5 matrix interactions 16). 

As a rule of thumb, a difference of 4 cm"1 in the Raman spectrum corresponds to a wavelength shift of 0,1 nm in the measured spectrum. To distinguish two spectral features 50 cm 1 apart, full spectral separation must be achieved over an interval of less than 2 nm. This effectively excludes filter solutions. Therefore, Raman arrangements practically always rely on spectrometers for spectral analysis. 

Glazer, A.N., and Stryer, L. (1983) Fluorescent tandem phycobiliprotein conjugates Emission wavelength shifting by energy transfer. Biophys. /. 43, 383-386. 

Rees and co-workers23 first studied the effect of the deposition of thin HRI overlays onto LPGs by analyzing the wavelength shift of the attenuation bands. The Langmuir-Blodgett deposition technique was exploited to deposit an incrementally thicker overlay (up to few hundreds of nanometers) of an organic material whose refractive index was 1.58. 

To experimentally prove the phenomenon of the modal transition and its effects on the sensitivity of nano-coated LPGs to SRI changes, the dip coating, as deposition technique, and the sPS, as HRI material, were used. Here the LPG sensitivity (different for each cladding mode) is defined as the gradient of the wavelength shift of the attenuation bands minima with respect to the SRI (d esj/dSRI). 

As a preliminary test, the experimental setup just described was used to characterize the bare LPG. In Fig. 3.15 it is reported that the central wavelength and the transmission loss peak of the attenuation band centred around 1,300 nm (related to the cladding mode LP06) as a function of the SRI. The refractive index sensitivity of the bare LPG was found to be 5.06 nm/RIU (refractive index units) and 3.59 dB/ RIU, around the water refractive index, in terms of wavelength shift and amplitude... 

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