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Reactive efforts

The only question is whether the effort will be proactive or reactive. Proactive efforts are led by the enlightened leadership of safety, engineering, and management communities reactive efforts are pushed by accidents, litigation, and overseas competition. [Pg.55]

As a conclusion, JUPITER experiment and analysis was found to possess sufficient consistency on the whole, especially for the prediction of criticality, space-dependency of C/Es in core region, and sodium void reactivity, which were persistent problems in the past JUPITER evaluations. It was also recognized that there is, however, some room for further improvements about the C28/F49 ratio, reaction rate distribution in blanket region, and Doppler reactivity. Efforts are now being conducted from various viewpoints such as re-evaluation of experimental and analytical errors, application of new most-detailed analytical tools, comparisons with other experimental cores, and refrnement of statistical tests for physical consistency. [Pg.124]

The zinc electrode has been a constant lure for electrochemists over the last 150 years and in every case it has been the death knell of the project. With its high energy density, low costs, and high reactivity, efforts have been continuously made to produce a good rechargeable system based on this electrode. [Pg.550]

These plans will be consolidated into one concise plan, with annexes for each river system within the western rivers. There have been numerous action plans in the past but they have not included all of the western rivers the plans had different terminology and the plans did not fully address each of the possible river extremes. The WAPs will establish common framework for proactive and reactive efforts, ensure safety of life and navigation, provide protection of infrastructure, and prevent marine casualties during periods of high water, high velocity, low water, and ice. [Pg.56]

The existence of the polyad number as a bottleneck to energy flow on short time scales is potentially important for efforts to control molecnlar reactivity rising advanced laser techniqnes, discussed below in section Al.2.20. Efforts at control seek to intervene in the molecnlar dynamics to prevent the effects of widespread vibrational energy flow, the presence of which is one of the key assumptions of Rice-Ramsperger-Kassel-Marcns (RRKM) and other theories of reaction dynamics [6]. [Pg.75]

Much effort has gone into detenuining these quantities since they are fundamental to ionic reactivity. Examples include thenuodynamic equilibrium measurements for all quantities and photoelectron studies for detenuination of EAs and IPs. The most up-to-date tabulation on ion thenuochemistry is the NIST Chemistry WebBook (webbook.nist.gov/chemistry) [123]. [Pg.815]

Cyclobutadiene escaped chemical charactenzation for more than 100 years Despite numerous attempts all synthetic efforts met with failure It became apparent not only that cyclobutadiene was not aromatic but that it was exceedingly unstable Beginning m the 1950s a variety of novel techniques succeeded m generating cyclobutadiene as a transient reactive intermediate... [Pg.451]

Other fairly recent commercial products, poly(vinyl amine) and poly(vinyl amine vinyl alcohol), have addressed the need for primary amines and their selective reactivity. Prior efforts to synthesize poly(vinyl amine) have been limited because of the difficulty hydrolyzing the intermediate polymers. The current product is prepared from /V-ethenylformamide (20) formed from the reaction of acetaldehyde and formamide. The vinyl amide is polymerized with a free-radical initiator, then hydrolyzed (eq. 7). [Pg.320]

Esterification. Extensive commercial use is made of primary amyl acetate, a mixture of 1-pentyl acetate [28-63-7] and 2-metliylbutyl acetate [53496-15-4]. Esterifications with acetic acid are generally conducted in the Hquid phase in the presence of a strong acid catalyst such as sulfuric acid (34). Increased reaction rates are reported when esterifications are carried out in the presence of heteropoly acids supported on macroreticular cation-exchange resins (35) and 2eohte (36) catalysts in a heterogeneous process. Judging from the many patents issued in recent years, there appears to be considerable effort underway to find an appropriate soHd catalyst for a reactive distillation esterification process to avoid the product removal difficulties of the conventional process. [Pg.373]

Efforts to raise the alpha-selectivity have been made. Thus nitration of anthraquinone using nitrogen dioxide and ozone has been reported (17). l-Amino-4-bromoanthraquinone-2-sulfonic acid (bromamine acid) [116-81 -4] (8) is the most important intermediate for manufacturing reactive and acid dyes. Bromamine acid is manufactured from l-aminoanthraquinone-2-sulfonic acid [83-62-5] (19) by bromination in aqueous medium (18—20), or in concentrated sulfuric acid (21). l-Aminoanthraquinone-2-sulfonic acid is prepared from l-aminoanthraquinone by sulfonation in an inert, high boiling point organic solvent (22), or in oleum with sodium sulfate (23). [Pg.310]

The first major objective for the inherent safety review is the development of a good understanding of the hazards involved in the process. Early understanding of these hazards provides time for the development team to implement recommendations of the inherent safety effort. Hazards associated with flammability, pressure, and temperature are relatively easy to identify. Reactive chemistry hazards are not. They are frequently difficult to identify and understand in the lab and pilot plant. Special calorimetry equipment and expertise are often necessary to fully characterize the hazards of runaway reactions and decompositions. Similarly, industrial hygiene and toxicology expertise is desirable to help define and understand health hazards associated with the chemicals employed. [Pg.117]

Two new sections on the protection of phosphates and the alkyne-CH are included. All other sections of the book have been expanded, some more than others. The section on the protection of alcohols has increased substantially, reflecting the trend of the nineties to synthesize acetate- and propionate-derived natural products. An effort was made to include many more enzymatic methods of protection and deprotection. Most of these are associated with the protection of alcohols as esters and the protection of carboxylic acids. Here we have not attempted to be exhaustive, but hopefully, a sufficient number of cases are provided that illustrate the true power of this technology, so that the reader will examine some of the excellent monographs and review articles cited in the references. The Reactivity Charts in Chapter 10 are identical to those in the first edition. The chart number appears beside the name of each protective group when it is first introduced. No attempt was made to update these Charts, not only because of the sheer magnitude of the task, but because it is nearly impossible in... [Pg.785]

Efforts to establish a theoretical explanation of the reactivity of nucleophilic reagents have centered on correlations with intrinsic electron-donor properties which are the fundamental basis of nucleophilicity. According to Edwards and Pearson, in general, such properties include basicity, polarizability, and the presence of unshared electron pairs on the atom adjacent to the nucleophilic atom of the reagent. When only the first two of these properties are operative, Eq. (8), which was proposed by Edwards, has proved successful in... [Pg.301]


See other pages where Reactive efforts is mentioned: [Pg.890]    [Pg.2627]    [Pg.135]    [Pg.80]    [Pg.454]    [Pg.157]    [Pg.554]    [Pg.417]    [Pg.75]    [Pg.203]    [Pg.321]    [Pg.447]    [Pg.448]    [Pg.46]    [Pg.301]    [Pg.237]    [Pg.285]    [Pg.413]    [Pg.313]    [Pg.294]    [Pg.82]    [Pg.406]    [Pg.411]    [Pg.136]    [Pg.208]    [Pg.18]    [Pg.739]    [Pg.898]    [Pg.10]    [Pg.454]    [Pg.586]    [Pg.4]    [Pg.701]    [Pg.706]   
See also in sourсe #XX -- [ Pg.55 ]

See also in sourсe #XX -- [ Pg.55 ]




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