Runaway selection

Suddendorf You would have to come up with some causal chain just having said that social complexity might be related to social intelligence doesn t explain anything, because the causality can go both ways. In order to explain why we have stayed in this mental arms race in social intelligence, you would have to either resort to a runaway selection mechanism, or argue for some spin-off benefit outside the social domain which allows you to support the investment in a larger brain. 

RUNAWAY SELECTION Genes for producing and detecting signal are linked... 

Runaway reactions, 405 Runaway reactions, DIERS, 521-523 Rupture, disk, 401, 418, 435, 455 Burst pressure, 456 Calculations, non-explosive, 455, 459 Code pressure levels, 410 Effects of temperature, 458 Graphite, 418-420, 424 Installation, 422, 423 Liquids, 462 Low pressure, 418, 421 Manufacturing range, 434, 456 Metal, 411 Non-fire, 465 Quick opening, 414, 415 Reverse buckling, 413 Selection features, 434... 

These methods hardly take spatial distributions of velocity field and chemical species or transient phenomena into account, although most chemical reactors are operated in the turbulent regime and/or a multiphase flow mode. As a result, yield and selectivity of commercial chemical reactors often deviate from the values at their laboratory or pilot-scale prototypes. Scale-up of many chemical reactors, in particular the multiphase types, is still surrounded by a fame of mystery indeed. Another problem relates to the occurrence of thermal runaways due to hot spots as a result of poor local mixing effects. 

Experimental data at the actual relief conditions are recommended for sizing relief vents for runaway reaction scenarios. As always, manufacturers technical specifications are used for selection, purchase, and installation. 

The reaction may proceed directly to phthalic anhydride, or it may proceed via naphthaquinone as an intermediate. Phthalic anhydride may also undergo subsequent conversion to CO, and HzO. Thus, the selectivity to phthalic anhydride is a crucial aspect of the design. Proper control of temperature is required to limit napthaquinone production and avoid the runaway (and possibly explosive) reaction which leads to the production of CO, and HzO. A fluidized-bed is thus preferred over a fixed-bed process. 

Contamination of peroxides has been a major source of accidents by runaway decompositions, particularly during handling and use. Therefore all equipment that is in contact with peroxides must be thoroughly cleaned. When a diluent is used, it should be properly selected and its purity must be strictly controlled. The use of dedicated loading/unloading equipment and avoidance of the use of shared or manifold equipment are methods to reduce the possibility of cross-contamination. 

Heat of reaction, selected by Heikkila et al. (1996), measures the energy available from the reaction. A high heat of reaction may generate higher temperatures and dangerous runaway reactions. Another parameter to consider controllability of a reaction is reaction rate. Reaction rate does not directly express the hazardousness of a reaction (e.g. when the heat of reaction is low). Thus it has been excluded from the list of chosen parameters. 

Radiation from Metal Rod 518 Relief of a Runaway Polymerisation Reaction 355 Optimized Selectivity in a Semi-Continuous Reactor 362... 

Miller, G. Evolution of the Human Brain Through Runaway Sexual Selection The Mind as a Protean Courtship Device. PhD thesis, University of California. 

De Jong, M. . M. and Sabelis, M. W. (1991). Limits to runaway sexual selection the wallflower paradox. Journal of Evolutionary Biology 4 637-655. 

Where the hazard is an exothermic runaway reaction, there are number, of alternative measures that may be used either to prevent or control runaway. Informatipn on the various options is in Annex 1. In the UK, one of the most commonly selected measures used to protect reactors from exothermic runaway is an emergency relief system. These have a number of advantages ... 

HE Huckins, "Selection and Design of Systems to Handle the Effluent from Emergency Relief Systems", International Symposium on Runaway Reactions and Pressure Relief Design, 710-741, AlChE, 1995, ISBN 0-8169-0676-9... 

Uncertainty is introduced at many stages in the sizing of pressure relief systems for runaway chemical reactions, and the application of a safety factor to offset this uncertainty may be appropriate. This Annex gives some guidance on the selection of an appropriate value for any safety factor. 

A Cooling Flow No 1. Control valve fails closed 1. Loss of cooling, possible runaway 1. Select valve to fail open DAC 1/93 ... 

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