Accelerative

Most of the LFRP research ia the 1990s is focused on the use of nitroxides as the stable free radical. The main problems associated with nitroxide-mediated styrene polymerizations are slow polymerization rate and the iaability to make high molecular weight narrow-polydispersity PS. This iaability is likely to be the result of side reactions of the living end lea ding to termination rather than propagation (183). The polymerization rate can be accelerated by the addition of acids to the process (184). The mechanism of the accelerative effect of the acid is not certain. 

Xylanase (from Streptomyces lividans) [37278-89-0] Mr 43,000 [EC 3.2.1.8]. Purified by anion-exchange chromatography on an Accell QMA column and finally by HPLC using a ProteinPak DEAE 5PW anion-exchange column. Solutions were stored frozen at -70°. [Morosoli et al. Biochem J 239 587 79S6 Wong et al. Microbiol Rev 52 305 1988.]... 

The role of moisture in corrosion of metals and other surfaces is twofold surface wetness acts as a solvent for containments and for metals is a medium for electrolysis. The presence of sulfate and chloride ions acceler-... 

A crystal material is excited by the force imposed on it by an internal I v mounted mass. A voltage is produced by the crystal proportional to accel eration. This voltage is then amplified by a charge amplifier type signal conditioner from whence the signal can be transmitted long distance. (1.000 feet is not uncommon) to the monitor/readout unit. It is calibrated in terms of gravitational units (g), which are proportional to force. Force is ttnc of the most reliable indicators of equipment distress. 

Bunnett and co-workers have shown that an or Ao-carboxy-late anion decreases the rate of reaction of 4-nitrochlorobenzene with methoxide ion but rather strongly increases the reaction rate with piperidine. This effect arises from an accelerative increase in the... 

The accelerative effect of electrostatic attraction between anions and positively charged substrates and the decelerative repulsion of like charges in the reagents is discussed in Sections I,D, 2,a and b, II,Bj4, and III, A, 2. 

The accelerative effect of the protonated form (68) arises from increased resonance stabilization of the charge and is much greater than that which would result from its ammonio analog (69), activating by induction. 

Reactions of iV -alkylated or arylated azinium compounds with nucleophiles proceed more readily than those of the parent, uncation-ized azines, and the ring tends to open. The iV -substituent may bring into play an accelerative effect from the London forces of attraction. Increased displaceability of the substituent in iV -alkyl-azinium compounds has been noted for 2-halopyridinium (87) 1-haloisoquinolinium, 4-halopyrimidinium, 4-methoxypyrid-inium (88), 4-phenoxy- and 4-acetamido-quinazolinium (89), 3-methylthiopyridazinium, and 2-car boxymethylthiopyrimidi-nium salts (90). The latter was prepared in situ from the iV -alkyl-pyrimidine-2-thione. The activation can be effectively transmitted to... 

The accelerative effect of London forces of attraction between a nucleophile and nearby substituents has been investigated in quinoline and benzene derivatives by Bunnett and co-workers, ii7b, 307 In 2-, 4-, and 6-arylsulfonyl-3-nitrochlorobenzene, Loudon and Shulman found that arylmercaptide ion, presumably through this effect, displaced the arylsulfonyl group while methoxide or ammonia displaced the nitro or chloro group. 

The relations in Scheme V take into account intranuclear and intemuclear resonance activation and the special cases of 2-Le-3-aza (poor) and 4-Le-8-aza (extremely poor) activation as well as the two groups of inductive activation the possibility of an accelerative peri effect in substitutions with protic nucleophiles is indicated by the sign for 4-Le-5-aza compounds. 

The accelerative effect of quaternization on the reactivity of 1-halo groups toward water, alcohol, or ammonia has been reported. ... 

When enrichment episodes occur in the real world, but not in the laboratory under federal certification tests, real-world emissions are significantly higher than predicted. Further complicating emissions prediction is that aggressive driver behavior and complex traffic flow characteristics play a large role in enrichment occurrence. Current vehicle activity simulation models can predict average speeds and traffic volumes very well, but poorly predict the hard-accel-eration events that lead to enrichment. 

These subsystems profoundly affect the fuel cell system performance. As an example, the inherently slow air (oxygen) electrode reaction must be acceler-... 

S. Sasaki, Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. 347 (1-3), 83 (1994). 

Vepfek-Siska ascribes the accelerative effects of inert electrolytes to catalysis by trace quantities of Cu ions. 

CAT, Treatment of Electroplating Waste, Center for Advanced Technology, Indore, India, 2005. Available at http //www.cat.emet.in/technology/accel/indus/wsa/ctl/chem effulent.html. 

Not only the photoreaction but also a pinacol rearrangement (Scheme 3) and a m-chloroperbenzoic acid oxidation (Table 7) occurred in the solid state, selectively and acceleratively. 

Martinelli and Nelson (M7) developed a procedure for calculating the pressure drop in tubular systems with forced-circulation boiling. The procedure, which includes the accelerative effects due to phase change while assuming each phase is an incompressible fluid, is an extrapolation of the Lockhart and Martinelli x parameter correlation. Other pressure drop calculation procedures have been proposed for forced-circulation phase-change systems however, these suffer severe shortcomings, and have not proved more accurate than the Martinelli and Nelson method. 

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