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State, defined

The free energy differences obtained from our constrained simulations refer to strictly specified states, defined by single points in the 14-dimensional dihedral space. Standard concepts of a molecular conformation include some region, or volume in that space, explored by thermal fluctuations around a transient equilibrium structure. To obtain the free energy differences between conformers of the unconstrained peptide, a correction for the thermodynamic state is needed. The volume of explored conformational space may be estimated from the covariance matrix of the coordinates of interest, = ((Ci [13, lOj. For each of the four selected conform-... [Pg.172]

The values of the thermodynamic properties of the pure substances given in these tables are, for the substances in their standard states, defined as follows For a pure solid or liquid, the standard state is the substance in the condensed phase under a pressure of 1 atm (101 325 Pa). For a gas, the standard state is the hypothetical ideal gas at unit fugacity, in which state the enthalpy is that of the real gas at the same temperature and at zero pressure. [Pg.532]

Enthalpy of Formation The ideal gas standard enthalpy (heat) of formation (AHJoqs) of chemical compound is the increment of enthalpy associated with the reaction of forming that compound in the ideal gas state from the constituent elements in their standard states, defined as the existing phase at a temperature of 298.15 K and one atmosphere (101.3 kPa). Sources for data are Refs. 15, 23, 24, 104, 115, and 116. The most accurate, but again complicated, estimation method is that of Benson et al. " A compromise between complexity and accuracy is based on the additive atomic group-contribution scheme of Joback his original units of kcal/mol have been converted to kj/mol by the conversion 1 kcal/mol = 4.1868 kJ/moL... [Pg.392]

In order to write down the microscopic equations of motion more formally, we consider a size N x N 4-neighbor lattice with periodic boundary conditions. At each site (i, j) there are four cells, each of which is associated with one of the four neighbors of site (i,j). Each cell at time t can be in one of two states defined by a Boolean variable where d = 1,..., 4 labels, respectively, the east, north,... [Pg.489]

Laws passed in some states define a drunk driver as one who drives with a blood alcohol level of 0.10% by mass or higher. The level of alcohol can be determined by titrating blood plasma with potassium dichromate according to the unbalanced equation... [Pg.99]

Equilibrium distribution of ortho and para states. Defined value. [Pg.618]

As shown in Fig. 21, in this case, the entire system is composed of an open vessel with a flat bottom, containing a thin layer of liquid. Steady heat conduction from the flat bottom to the upper hquid/air interface is maintained by heating the bottom constantly. Then as the temperature of the heat plate is increased, after the critical temperature is passed, the liquid suddenly starts to move to form steady convection cells. Therefore in this case, the critical temperature is assumed to be a bifurcation point. The important point is the existence of the standard state defined by the nonzero heat flux without any fluctuations. Below the critical temperature, even though some disturbances cause the liquid to fluctuate, the fluctuations receive only small energy from the heat flux, so that they cannot develop, and continuously decay to zero. Above the critical temperature, on the other hand, the energy received by the fluctuations increases steeply, so that they grow with time this is the origin of the convection cell. From this example, it can be said that the pattern formation requires both a certain nonzero flux and complementary fluctuations of physical quantities. [Pg.248]

In principle, one can extract from G(ti)) the complete series of the primary (one-hole, Ih) and excited (shake-up) states of the cation. In practice, one usually restricts the portion of shake-up space to be spanned to the 2h-lp (two-hole, one-particle) states defined by a single-electron transition, neglecting therefore excitations of higher rank (3h-2p, 4h-3p. ..) in the ionized system. In the so-called ADC[3] scheme (22), elertronic correlation effects in the reference ground state are included through third-order. In this scheme, multistate 2h-lp/2h-lp configuration interactions are also accounted for to first-order, whereas the couplings of the Ih and 2h-lp excitation manifolds are of second-order in electronic correlation. [Pg.81]

The chronic carrier state, defined as positive stool or urine cultures for more than 12 months, develops in 1% to 4% of adults with typhoid fever. Persistence of the organism, in many cases, is due to billiary tract carriage, and the frequency of chronic carriage is higher in persons with biliary abnormalities. [Pg.1119]

Figures 3 and 4 were obtained using the steady state defined by the variables and parameters of Tables I and II. Table III shows the poles and time constants computed from the A matrix for this steady state. Figures 3 and 4 were obtained using the steady state defined by the variables and parameters of Tables I and II. Table III shows the poles and time constants computed from the A matrix for this steady state.
Number of unpaired electrons/ground spin state defines antiferromagnetic and ferromagnetic interactions quantitates ground sublevel splittings For 57Fe sites oxidation and spin state ... [Pg.63]

As has already been discussed in the context of (1.19), the probability density function of finding the reference system in a state defined by positions x and momenta px is... [Pg.35]

The measurement of an enthalpy change is based either on the law of conservation of energy or on the Newton and Stefan-Boltzmann laws for the rate of heat transfer. In the latter case, the heat flow between a sample and a heat sink maintained at isothermal conditions is measured. Most of these isoperibol heat flux calorimeters are of the twin type with two sample chambers, each surrounded by a thermopile linking it to a constant temperature metal block or another type of heat reservoir. A reaction is initiated in one sample chamber after obtaining a stable stationary state defining the baseline from the thermopiles. The other sample chamber acts as a reference. As the reaction proceeds, the thermopile measures the temperature difference between the sample chamber and the reference cell. The rate of heat flow between the calorimeter and its surroundings is proportional to the temperature difference between the sample and the heat sink and the total heat effect is proportional to the integrated area under the calorimetric peak. A calibration is thus... [Pg.313]

Note Some states define decontaminated surety material as a RCRA Hazardous Waste. [Pg.432]

TA1 and TA2 are sets (not true types) to which members of TA belong when in a given state defined by a predicate on TA (usually in terms of attributes of TA, but see Section 3.11). If the determining attributes are not const, then objects can migrate across the state types otherwise, the classification of an object is fixed by the determining attributes at the time of its creation a TA is also a TA1 if it has property x[Pg.142]

For each state, define an invariant that relates it to other attributes in the type model. States are boolean attributes, and can be parameterized just like attributes. [Pg.620]

UML has three distinct constructs that remain largely unrelated to one another an attribute, a role in an association, and a state in a state chart. For example, a pie- and postcondition pair cannot refer to the name of a state. In Catalysis these three constructs are closely related. An association defines a pair of inverse attributes that are drawn differently a state defines a Boolean attribute, and the structure of states in a state chart defines invariants on those attributes. Transitions on a state diagram are thus no more than a graphical depiction of action specifications. This approach provides a simpler core set of constructs with different presentations. Actions on UML state transitions are imperative and appear unrelated to pre- and postspecification of operations. [Pg.716]

Hence for an electron in the state defined by quantum numbers n, 1, u (equation 4 a,111) above) we have... [Pg.154]

In the quantum mechanical description (in continuation of Box 2.2), the wavefunction can be described by the product of an electronic wavefunction VP and a vibrational wavefunction / (the rotational contribution can be neglected), so that the probability of transition between an initial state defined by ViXa and a final state defined by TQ/b is proportional to electron coordinates, this expression can be rewritten as the product of two terms < f i M vP2> 2 Franck-Condon factor. Qualitatively, the transition occurs from the lowest vibrational state of the ground state to the vibrational state of the excited state that it most resembles in terms of vibrational wavefunction. [Pg.31]


See other pages where State, defined is mentioned: [Pg.115]    [Pg.1065]    [Pg.392]    [Pg.15]    [Pg.246]    [Pg.402]    [Pg.1363]    [Pg.390]    [Pg.608]    [Pg.709]    [Pg.88]    [Pg.80]    [Pg.20]    [Pg.61]    [Pg.92]    [Pg.172]    [Pg.205]    [Pg.378]    [Pg.81]    [Pg.20]    [Pg.62]    [Pg.143]    [Pg.153]    [Pg.743]    [Pg.359]    [Pg.14]    [Pg.106]    [Pg.133]    [Pg.63]   
See also in sourсe #XX -- [ Pg.385 ]

See also in sourсe #XX -- [ Pg.4 ]




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