Activity pattern

Winter, another early pioneer of the study of oxygen exchange, has made a thorough investigation of the kinetics of Ri and R2 exchange over 38 inorganic oxides, and the results are reproduced in Tables 2 and 3.l l The 

Hargreaves JSJ Mellor IM Table 2. Oxygen exchange reactions oxide outgassed. 

Oxide B.E.T. To (°C) Reaction Temp. (°C) Main Reaction logic (Ac) E (kcal mopi) log 10 (rate)35o logic (rate)3oo m 

Although the activities have been determined under differing reaction temperatures, they have been extrapolated to 300°C and 350°C as a means of comparison. The data in the tables illustrates a number of features of the reaction. Comparison has been made between the conditions of pretreatment, such as vacuum versus oxygen atmospheres. The temperature of the vacuum pre-treatment was carefully controlled, as previous studies had shown that when the sample was pre-heated too high in vacuum, a 

---

The Modeling Engine in THERdbASE has the following model groups 1) Population Distributions, 2) Location/Activity Patterns, 3) Food Consumption Patterns, 4) Agent Releases Characteristics, 5) Microenvironment Agent Concentrations, 6) Macroenvironment Agent Concentrations, 7) Exposure Patterns and Scenarios, 8) Dose Patterns, and 9) Risk Assessment. 

Data files on the THERdbASE CD are 1990 Bureau of Census Population Information, California Adult Activity Pattern Study (1987-88), AT T-sponsored National Activity Pattern Study (1985), Chemical Agents from Sources, Chemical Agent Properties, Air Exchange Rates, Information from EPA s TEAM (Total Exposure Assessment Methodology) Studies, Information from EPA s NOPES (NonOccupational Pesticides Exposure Study) Studies, Information from EPA s AIRS (Aerometric Information Retrieval System), and Human Physiological Parameters. 

Brain scans are used to study epiiepsy, brain tumors, strokes, Aizheimer s disease, and mentai iiiness. Each of these disorders generates a unique brain activity pattern that differs from the pattern seen in normai brains. Physicians interpret these patterns both for diagnosis and to indicate appropriate treatment. 

Pariente, J. Perez-. An investigation on the activity pattern of alchemical transmutations. JSci Exploration 16, no. 4 (Dec 2002) 593-602. 

The breathing rate data used to define the BR variable were adapted from the reported distribution generated from Shamoo et al.3 In the Shamoo study, a different distribution was identified for several activity patterns, and for this simulation the slow, medium, and fast rate classifications were combined. The distribution is shown in Figure 3. 

Shamoo, D.A., Johnson, T.R., Trim, S.C., Little, D.E., Linn, W.S., and Hackney, J.D., Activity patterns of a panel of outdoor workers exposed to oxidant pollution, Journal of Exposure Analysis and Environmental Epidemiology, 1(4), 423-438, 1991. 

The simplest approach is to simply identify the likelihood of contact between people and pollutant at significant concentrations. This is often the extent of "risk" analysis of preliminary, multi-media, problem-scoping studies of hazardous or toxic materials (2). In the most detailed approach, finely resolved spatial and temporal patterns ("micro-environments") of concentration are measured for each of many individuals representing finely resolved population groups ("cohorts") characterized by unique "activity patterns" (3, 4 ). 

Datta, S. Siwek, D. F. (2002). Single cell activity patterns of pedunculopontine tegmentum neurons across the sleep-wake cycle in the freely moving rats. J. Neurosci. Res. 70, 611-21. 

A comparison of various metals as catalysts for the hydrogenolysis of hydrocarbons reveals a wide variation in catalytic activity, even among such closely related metals as the noble metals of group VIII of the periodic table. Striking differences in the distribution of hydrogenolysis products have also been revealed in studies on selected hydrocarbon reactants. These features are emphasized in the following discussion of activity patterns and product distributions in hydrogenolysis. 

Comparisons of the activities of various metal catalysts for reactions of hydrocarbons involving hydrogen as a reactant or product reveal activity patterns which are strongly dependent on the particular reaction considered. Several examples are discussed in the following subsections of this article. 

Fig. 4. Comparison of activity patterns of the group VIII noble metals for cyclopropane hydrogenation and ethane hydrogenolysis. The activities were all determined at hydrogen and hydrocarbon partial pressures of 0.20 and 0.030 atm, respectively (63).

The activity of the transition metals, especially for the chemisorption of molecular hydrogen and in hydrogenation reactions has been correlated, in the past, with the existence of partially filled d bands. Many alloy studies were prompted by the expectation that catalytic activity would change abruptly once these vacancies were filled by alloying with a group IB metal. Examples of such behavior have been collected together for the Pd-Au system (1). It is to be expected also that various complications might superimpose on the simple activity patterns observed for primitive... 

It was claimed that this model helps to explain earlier catalytic results using Cu-Ni alloys, but comparisons with alloys in granular, or other massive form, are difficult. The available catalytic results on Cu-Ni alloys show that the method of preparation of the catalyst can have a profound influence upon the observed activity pattern. The promoting effect on the catalytic activity, caused by cooling in hydrogen rather than in vacuum... 

Robel, R.J., R.W. Felthousen, and A.D. Dayton. 1983. Effects of dietary carbofurans on bobwhite activity patterns. Bull. Environ. Contam. Toxicol. 30 105-109. 

Neele SJ, Rombouts SA, Bierlaagh MA, Barkhof F, Scheltens P, Netelenbos JC (2001) Raloxifene affects brain activation patterns in postmenopausal women during visual encoding. J Clin Endocrinol Me tab 86 1422-1424... 

---