Quenching 260 INDEX

As an example, the battery-limits capital cost can be estimated for the production of 10,000 t/yr of ethylene (qv) from ethanol (11). Seven processing blocks, ie, vaporizer, reactor, water quench, compressor, dryer, distillation, and energy recovery, can be identified. The highest temperature is 350°C (reactor), and the highest pressure is about 1.7 MPa (17 atm) (compressor, two towers). If a materials-pressure factor, + of 1.03 is assumed, then for N = 7 0 = 0.87 1/0 = 1 64 and f =0 K = 6.3. This gives the 1981 cost as 4.4 X 10 . The 1991 battery-Hmits investment can be obtained, by updating with the CE Plant Cost Index, as 5.3 x 10 . ... 

Semicrystalline polyalkyl terephthalates are opaque due to diffraction of light as it crosses the interface between crystalline and amorphous regions. Amorphous polyethylene terephthalate has a low refractive index, making it appear glass-like in quenched parts. 

Thus, E is defined as the product of the energy transfer rate constant, ku and the fluorescence lifetime, xDA, of the donor experiencing quenching by the acceptor. The other quantities in Eq. (12.1) are the DA separation, rDA the DA overlap integral, / the refractive index of the transfer medium, n the orientation factor, k2 the normalized (to unit area) donor emission spectrum, (2) the acceptor extinction coefficient, eA(k) and the unperturbed donor quantum yield, QD. 

A solution of 14 g of the distilled, solid 4-ethoxy-3-methoxyphenol in 20 mL MeOH was treated with a solution of 5.3 g KOH in 100 mL hot MeOH. There was then added 11.9 g methyl iodide, and the mixture was held at reflux temperature for 2 h. The reaction was quenched with 3 volumes H.O, made strongly basic by the addition of 1 volume of 5% NaOH, and extracted with 2x150 mL E O. Pooling the extracts and removal of the solvent under vacuum gave 9.7 g of 2.4-dimethoxy-1-ethoxybenzene as a clear, off-white oil that showed a single peak by GC. An acceptable alternate synthesis of this ether i s the ethylation of 2,4-dimethoxyphenol, whichisdescribedintherecipeforTMA-4. The index of refraction was nD25 = 1.5210. 

Fig. 3 Dissolving kinetics (in terms of average hydrodynamic radius Rh) of collapsed single-chain PNIPAM globules, where t is the standing time after the solution temperature was quenched from 33.02 to 30.02 °C and the dashed line represents a stable average value of Rh of individual PNIPAM random coils at 30.02 °C. The weight-average molar mass (Mw) of the PNIPAM sample used is 1.08 x 107g/mol with a polydispersity index (Mw/Mn) less than 1.1 [32]...

Luminescence lifetime depends upon radiative and nomadiative decay rates. In nanoscale systems, there are many factors that may affect the luminescence lifetime. Usually the luminescence lifetime of lanthanide ions in nanociystals is shortened because of the increase in nomadiative relaxation rate due to surface defects or quenching centers. On the other hand, a longer radiative lifetime of lanthanide states (such as 5Do of Eu3+) in nanocrystals can be observed due to (1) the non-solid medium surrounding the nanoparticles that changes the effective index of refraction thus modifies the radiative lifetime (Meltzer et al., 1999 Schniepp and Sandoghdar, 2002) (2) size-dependent spontaneous emission rate increases up to 3 folds (Schniepp and Sandoghdar, 2002) (3) an increased lattice constant which reduces the odd crystal field component (Schmechel et al., 2001). 

Our first attempts at a straight-forward analysis of these two compounds was frustrated by the broad, structureless and highly overlapping spectra. However, it was known from previous studies that the parent s fluorescence is quenched under acid conditions whereas that of the metabolite is relatively unaffected. This fact suggested that a higher order strategy could be devised an EEM would be obtained under two pH conditions, acid and base. In this case, the data would be an array T indexed by three subscripts ... 

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