Proximity effects minimizing

Industrial Power Engineering and Applications Handbook 28.8.4 Minimizing the proximity effect... 

No properly constituted data sets for reaction rates were found for which eq. (1) is followed with acceptable precision (34). This result may be attributed to the incursion of proximity effect contributions. However, certain benzoic acid type ionization equilibria data sets do appear to follow eq. (1) satisfactorily, although none of the sets qualifies as a minimal basis set. Table XXVII summarizes the results for the fittings with parameters, which for every discriminating... 

Figure 5-6, and tries to couple very closely with the forward trace. In doing so, it attempts to cancel the fields produced by the forward trace. It is nature s way of helping us, if we just let it. We should realize that inductance exists only because of the field it produces and vice versa. The field contains the associated stored energy of 1/2 x LI2. Then if the field is somehow canceled, so is the inductance. Proximity effects are also minimized by the paralleling of these opposite traces, and therefore AC resistance is also reduced. 

Electron Beam Lithography. LB PMMA films with thicknesses of 6.3 nm (7 layers) are sufficient for patterning a Cr film suitable for photomask fabrication. For ultrathin PMMA films the resolution (see Fig. 1) is limited by the smallest spot diameter available on MEBES I (1/8 pm). However, it is not possible to obtain this resolution if a thicker resist (>100 nm) is used under the same exposure and development conditions, which demonstrates that ultrathin resists are able to minimize the proximity effect. Also, since the radius of gyration of 188,100 Mw PMMA is about 10 nm in the bulk, and the thickness of the 7 layer film (6.3 nm) is less than 10 nm, it is reasonable to assume there must be an alteration of chain configuration in the ultrathin films. This will be particularly true when the post-deposition baking temperature of the multilayer films is less than the glass transition temperature (115°C), as is the case for the present experiments. In such a case, interdiffusion of PMMA chains between the deposited layers may not result in chain configurations characteristic of the bulk. 

Another method for minimizing the proximity effect involves changing the electron beam acceleration potential from the 10 to 20 KV range that is typically used in direct write applications. L. D. Jackel and co-workers have proposed that increasing the acceleration potential to 100 KV will minimize the need for proximity corrections as the backscattered electrons will be averaged over a larger area (2). While this approach may reduce the effect of backscattered electrons, it will also significantly reduce the resist sensitivity since a smaller number of electrons will be deposited in the resist at 100 KV. 

Figure 28.17(b) Minimizing the effect of proximity in thicker sections (Section 28.8.4)... 

Figure 28.29 Minimizing the effects of skin and proximity through phase interleaving...

The dummy tubes do not pass through the tubesheets, and can be located close to the inside of the shell. The seating strips extend from baffle to baffle in a longitudinal direction and effectively channel the fluid across the tubes to minimize turbulence and heat transfer. On some fixed tubesheet designs, the outer tubes are in close proximity to the inside of the shell so that by-pass is minimal and no by-pass elimination is necessary. There are a number of... 

Modifier additives also play a role in method optimization and are typically added to the modifier at concentrations less than 1 % (v/v). Additives can provide increased efficiency by minimizing undesirable interactions between the analyte and the CSP, and may be necessary to elute certain types of compounds. The type of additive (acidic or basic) that will produce the best results depends upon the functionality of the analyte [72]. Certain additives are strongly retained on the stationary phase, and their effect may persist even after they are removed from the eluent [22]. The impact of both modifiers and additives can also be affected by the proximity of the operating conditions to the critical point of the eluent [73]. 

Separation-based assays are preferred in many applications because they allow discrimination of signals due to substrate, product, and interference. When assays that involve fluorescence detection are developed, they are typically carried out by employing plate readers. When separation-based methods are employed for these applications, the influences of interferences (quenchers and other fluorescent compounds) on the final results are minimized because both substrate and product are quantified. With a separation-based approach, the label employed does not need to be placed in close proximity to the site of action of the enzyme, therefore minimizing the effect of the label on the mode of action of the enzyme. Of course, it is often desirable to develop assays that employ substrates free of labels. 

Rats exposed 5 days/week for 13 weeks to concentrations as high as 7060 ppm showed minimal effects to the nervous system as determined by functional observational battery, automated motor activity, and neuropathology. Rats exposed 6 hours/day for 90 days at 7100 ppm had increased liver and kidney weights males also had liver cell hypertrophy and increased hyaline droplets in the proximal tubules. ... 

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