Activity Theory

Van Aalsvoort, J. (2004b). Activity theory as a tool to address the problem of chemistry s lack of relevance in secondary school chemical education. IntemationalJoumal of Science Education, 26(13), 1635-1651. 

Broke, B., and Battmann, W., The arousal-activation theory of extraversion and neuroticism A systematic analysis and principal conclusions. Advances in Behaviour Research and Therapy 14(4), 211-246, 1992. 

Kapsalis, J.G. 1987. Influence of hysteresis and temperature on moisture sorption isotherms. In Water Activity Theory and Application to Foods (L.B. Rockland and L.R. Beuchat, eds), pp. 173-213. Dekker, New York. 

If these conclusions are valid they have important implications for the design of tests to evaluate relative toxicity and also for structure/activity theories for example if the relationship between polarity and toxicity is strongly influenced by decay processes then it is important that these are given appropriate consideration in designing candidate compounds. The analysis presented above also gives a strong support for further pharmacodynamic studies of pesticide action... 

The district court rejected both the strict product liability and the ultrahazardous activity theory in Perkins s suit and granted summary judgment in favor of the gun manufacturer. In a similar case, Richman v. Charter Arms Corp. (involving a robbery, rape, and murder committed using a. 38 caliber handgun), the court granted summary judgment to the defendant on product liability but not on ultrahazardous activity. The two cases were then combined in an appeal to the U.S. Circuit Court of Appeals, Fifth District. 

Rockland, L.B. and Beuchat, L.R. (eds) (1987) Water Activity Theory and Applications to Food, Marcel Dekker, New York. 

Chaiklin, S., Hedegaard, M. and Jensen, U.J. (eds) 1999. Activity Theory and Social Practice. 

Several methods to evaluate the temperature variation ofDiw are given in Box 18.4. As an example we use the values for trichlorofluoromethane (CFC-11) calculated from the activation theory model (see Box 18.4, Eq. 2) ... 

BrOnsled showed the inadequacy of both the classical and the activity theories of rate of certain reactions. He proposed a new theory postulating that when ions or molecules react, they first form an unstable critical complex, which then decomposes to give the reaction products. The reaction that determines the velocity of a chemical change consists in the formation nf that unstable critical complex. 

Because of the large number of dyestuffs and the fact that most of these colorants have not been tested for carcinogenicity, structure-activity theory may help predict possible candidates Tor study. 

For infinitely dilute solutions activity coefficients approach unity so the activity and the concentration of an ion will be equal. For calculations involving more concentrated solutions corrections must be made using activity coefficients, especially when relating the calculated concentration of species to an imposed mass (mole) balance constraint. The activity coefficients can be calculated from a number of ion activity theories and the relevant equations for some of the commonly used ones are shown below. 

Bone, D.P. 1987. Practical applications of water activity and moisture relations in foods. In Water activity Theory and application to food, ed. L.B. Rockland and L.R. Beuchat. New York Marcel Dekker, Inc. 

I. lancu A. Olmer R. D. Strous, Caffeinism History, Clinical Features, Diagnosis, and Treatment. In Caffeine and Activation Theory) B. D. Smith, U. Gupta, B. S. Gupta, Eds. CRC Press LLC Boca Raton, FL, 2007 pp 331-347. 

Rhee H, Ha JH, Jeon SJ et al (2008) Femtosecond spectral interferometry of optical activity theory. J Chem Phys 129 094507... 

Kinetics of Yielding. Tensile yield stresses were measured at several Instron rates for block polymer B. These results and those of Bauwens-Crowet et ah (9) for BPA polycarbonate were analyzed in the framework of the Rhee-Eyring stress bias activation theory for comparison purposes. Yield stress of the block polymer is roughly half that of the homopolymer at a given temperature. The apparent activation volume for the block polymer is double that of the homopolymer at each temperature. Activation energies at zero stress are essentially the same (60 kcal/mole for the block polymer vs. 70 kcal/mole for BPA polycarbonate above —50°C). 

As the authors indicated, the activity of these opioid aromatic ethers could not have been anticipated from any known structure-activity theory. ... 

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