State inaccessible

Dashes indicate inaccessible states blanks indicate no available data. 

In addition, we have established that there is a sense of direction to the location of the inaccessible states. State 2, the state reached from 1 by a reversible adiabatic path, represents the division between the states on the second isotherm that are accessible and inaccessible from state 1. We represent this schematically in Figure 2.1 lb, where the reversible adiabatic path separates states that are accessible from state 1 from those that are inaccessible. The observation that the reversible path serves as the boundary between the two sets of states will be useful later when we show the direction of allowed processes in terms of the sign of A5(universe). 

In the analysis in Section 2.2b, we showed that for any given initial state there are states that are accessible via irreversible adiabatic paths from the initial state, as well as states that are inaccessible from that initial state by way of irreversible adiabatic paths. Figure 2.11b showed that a reversible adiabatic path containing the initial state marked the division between the states that were accessible or inaccessible from that state, with all accessible states lying on one side of the reversible adiabatic path, and all inaccessible states lying on the other side of it. 

Schottky effect in solids 580-5 Second law of thermodynamics 56-90 absolute temperature, identification of as integrating factor 71-8 Caratheodory principles differentials 63-7 and inaccessible states 68-71... 

The identification of excited states in strong field interactions with molecules has lead to some novel forms of molecular spectroscopy, allowing previously inaccessible states to be studied. For the most part, this comes from the ability to do transient spectroscopy in the time domain with ultrashort pulses. But, the strong field interaction also allows for new population mechanisms. 

Not illustrated is the use of multiphoton excitation of fluorescence (12.15). thus far demonstrated in flame systems only for excitation of atoms. It affords the means to excite otherwise inaccessible states and offers other potential advantages in spatial resolution and for optically thick flames, in spite of inherently low signal levels. 

Dashes indicate inaccessible states blanks indicate no available data. TABLE 2-183 Compressibility Factors for Refrigerant 124... 

Dashes indicate inaccessible states. Average uncertainty is about 20 percent. Values derived from formulations for thermal conductivity, specific heat at constant pressure, and viscosity contained in Thermophysical Properties of Refrigerants. American Society of Heating, Refrigerating and Air-Conditioning Engineers, New York, 1976. For further details see M. W. Johnson, M.S.M.E. thesis, Purdue University, West Lafayette, Ind., 1976. 

Selection rules are the real key to spectroscopy. Without them, transitions between so many levels would be possible that reconstructing energy level diagrams from observational data would become an almost insuperable task. However, since selection rules may hinder accessing certain excited states, it is also necessary to know experimental means of violating them, so that one can, where necessary, reach otherwise inaccessible states. Thus, in a spectrum in which only singlet states can be photo-excited, it may prove useful that electron impact excitation can violate the... 

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