Environment, changing the

Tzolova-Miiller et al. (unpublished data) followed the dehydration of VOx/SBA-15, shown in Figure 14. The spectra provide a good example illustrating the usefulness of simultaneously acquired NIR data. The band at 1902 nm is typical for adsorbed water, and it can be seen by comparing the UV-vis and the NIR range that the vanadium environment changes the moment water desorbs (i.e., as the respective band vanishes). 

Simple treatments, such as heating the carbon in steam or in an oxidizing environment, change the surface structure. The surface porosity increases63 due to operation of the Boudouard reaction ... 

Fig. 9 Decrease of friction force upon environment change from ambient humid air to saturated alcohol vapor. The friction signals are normalized to the initial friction signals measured in ambient air for each experiment to minimize errors because of tip diameter variance in each measurement and emphasize the relative change because of condensed alcohol layer formation. The inset shows temporal changes of friction force upon sudden environment changes. The applied normal signal is kept constant at 75 nN. (View this art in color at WWW. dekker. com.)...

SUTTON inquired about how far it is possible at present to make significant comparisons between interatomic distances observed in the gas phase and in the crystal phase. Chemists need to do this to find out whether environment changes the structure of a molecule. Significant is an arbitrary word, but may be defined as a difference of more than 0.005 A. HEDBERG seemed to best summarize the discussion that followed. He stated that there had been no concerted attempt known to him to compare solid-state and gas-phase results, but that there are a number of examples where differences are large. It was agreed that such comparative studies should certainly be made. TUKEY s feeling was that it was inappropriate until we first examined the reliability of the results obtained by each of the various methods. Once we can estimate standard deviations that include the systematic errors properly, then we can have a basis for informed discussion. 

The reaction of a many-electron system to a time-dependent perturbation is almost as important as its adjustment to a static time-independent environment change. The theory of the first-order response of a system to an oscillating field follows very similar lines to the perturbation theory of the last chapter. 

What are appropriate roles for the computer in creating test environments ("delivery" of tests) and in assessing students perfomoance (How might the dynamics of interactive process oriented environments change the nature of the Unds of "items" that are given to students )... 

Many project investment decisions are the result of significant analysis of various projects. The decision is based on analyses and the assumption that the organization commits large sums of money upfront to a project, and if the project fails, the company has lost most if not all of the investment. This approach can be risky as the business environment changes. The viability of a project can be seriously questioned if the assumptions that led to a project being selected have changed. In the same way, a project that appeared unfeasible can become viable with changes in the business environment. 

Second, Collins s notion of the tacit presumes that apprentices will replicate a previously working artifact. New lasers are said to fail if they fail to work in similar, predictable, and controlled laboratory environments. In the mines, however, apprentices may replicate previous procedures, follow fully articulated rules and procedures, and still fail because new situations and environments change the conditions that enabled previous models to succeed. 

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