Retardation definition

Luckasson, R., Coulter, D.L., Polloway, E.A., Reiss, S., Schalock, R.L. and Snell, M.E. (1992). Mental Retardation Definition, Classification and Systems of Support. American Association of Mental Retardation, Washington, DC. 

One problem associated with discussing flame retardants is the lack of a clear, uniform definition of flammabiHty. Hence, no clear, uniform definition of decreased flammabiHty exists. The latest American Society for Testing and Materials (ASTM) compilation of fire tests Hsts over one hundred methods for assessing the flammabiHty of materials (2). These range in severity from small-scale measures of the ignitabiHty of a material to actual testing in a full-scale fire. Several of the most common tests used on plastics are summarized in Table 1. 

VAc polymerization 294 retarders 264 7 definition 264 reverse transfer constant... 

In a practical sense, stability of a dispersion ofttimes is accompanied by a retarded separation of the phases. Unfortunately, a quantitative definition cannot be based on this rate of separation because of the overwhelming influence of density, viscosity, and thermal effects. In short, a kinetic criterion, such as sedimentation rate, is not as likely to portray stability as one based on thermodynamic considerations. In this latter category are sediment volumes, turbidity, consistency, and electrical behavior. 

With a growing implementation of the thin-layer chromatographic laboratories with densitometric scanners and particularly in the case of PLC, it seems quite important to reconsider definition of the Rp coefficient and the ways of its determination. Further, it seems strongly advisable to recommend the retardation factor in its i P(max) form as a more practical one for the preparative layer chromatographic usage. 

Finally, an officially updated definition of the retardation factor, R, issued by lUPAC is important to the whole field of planar chromatography (the linear and the nonlinear TLC mode included). The importance of such a definition has two reasons. First, it is promoted by the growing access of planar chromatography users for densitometric evaluation of their chromatograms and second, by the vagueness of the present definition in the case of skewed concentration profiles with the samples developed under mass overload conditions. 

The agents in this class are bicyclophosphates and bicyclothiophosphates. This class of agents is not specifically listed in the Chemical Weapons Convention nor is it covered by the language of the general definitions in the Schedules. Some of these chemicals have been used as fire retardants, oil lubricants, and for medicinal research. They also occur as breakdown products in some synthetic turbine engine lubricants and some rigid polyurethane foams. 

Definitions of mental illness tend to contain two aspects a normative element and a functional element. Normative definitions delimit abnormal behavior in light of what is typical, usual, or the norm. Some degree of deviance from the norm is necessary for a behavior to be considered abnormal. Deviance alone, however, is never sufficient for a label of abnormality. High IQ is just as deviant as low IQ, but only mental retardation is labeled abnormal. This leads us to the functional element of the definition. Typically, the label of abnormality requires deviance plus maladaptation. Maladaptation suggests some diminished capacity to function relative to an average. For example, the DSM defines mental disorder as a syndrome that is associated with distress or impairment in functioning (American Psychiatric Association, 1994, pp- xxi-xxii). 

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