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2- form conservation

The complete picture about equivalences is achieved by asserting that objects that do not follow the Pauli exclusion principle do not form conservative dipoles. The Second Principle of Thermodynamics, in which entropy can only stay constant or increase during a transformation, can be translated to state that a thermal dipole is not conservative or that entropy behaves as bosons. [Pg.194]

Eigure a shows that the eigensurfaces form an interconnected double sheet, the lower member of which has a ring of equivalent minima at r = and IV = — k. As expected angular momentum is conserved, but with the complication that it is vibronic, rather than purely vibrational in character. [Pg.18]

If there are no reactions, the conservation of the total quantity of each species dictates that the time dependence of is given by minus the divergence of the flux ps vs), where (vs) is the drift velocity of the species s. The latter is proportional to the average force acting locally on species s, which is the thermodynamic force, equal to minus the gradient of the thermodynamic potential. In the local coupling approximation the mobility appears as a proportionality constant M. For spontaneous processes near equilibrium it is important that a noise term T] t) is retained [146]. Thus dynamic equations of the form... [Pg.26]

A mapping is said to be symplectic or canonical if it preserves the differential form dp A dq which defines the symplectic structure in the phase space. Differential forms provide a geometric interpretation of symplectic-ness in terms of conservation of areas which follows from Liouville s theorem [14]. In one-degree-of-freedom example symplecticness is the preservation of oriented area. An example is the harmonic oscillator where the t-flow is just a rigid rotation and the area is preserved. The area-preserving character of the solution operator holds only for Hamiltonian systems. In more then one-degree-of-freedom examples the preservation of area is symplecticness rather than preservation of volume [5]. [Pg.335]

We will assume in this article that the system is time-reversible, so T(p) = T —p). Dichotomic Hamiltonians arise from elementary particle models, the simplest nontrivial class of conservative systems. Moreover, even seemingly more complex systems can usually be written in the dichotomic form through change of variables or introduction of additional degrees of freedom. [Pg.353]

The bond orders obtained from Mayer s formula often seem intuitively reasonable, as illustrated in Table 2.6 for some simple molecules. The method has also been used to compute the bond orders for intermediate structures in reactions of the form H -1- XH HX -1- H and X I- XH -H H (X = F, Cl, Br). The results suggested that bond orders were a useful way to describe the similarity of the transition structure to the reactants or to the products. Moreover, the bond orders were approximately conserved along the reaction pathway. [Pg.103]

Conservation of reaction units requires that the number of reaction units associated with the reactant A equal the number of reaction units associated with the reactant B. Translating the previous statement into mathematical form gives... [Pg.21]

The stoichiometry between two reactants in a precipitation reaction is governed by a conservation of charge, requiring that the total cation charge and the total anion charge in the precipitate be equal. The reaction units in a precipitation reaction, therefore, are the absolute values of the charges on the cation and anion that make up the precipitate. Applying equation 2.3 to a precipitate of Ca3(P04)2 formed from the reaction of Ca and P04 , we write... [Pg.22]

An equation stating that matter is conserved, and that the total amount of a species added to a solution must equal the sum of the amount of each of its possible forms present in solution. [Pg.159]

The desired final precipitate, Mg2P207, contains two moles of Mg, and the impurity, Mg(P03)2, contains only one mole of Mg. Conservation of mass, therefore, requires that two moles of Mg(P03)2 must form in place of each mole of Mg2P207. One mole of Mg2P207 weights 222.6 g. Two moles of Mg(P03)2 weigh 364.5 g. Any replacement of Mg2P207 with Mg(P03)2 must increase the precipitate s mass. [Pg.247]

Conserva.tlon, Because the most common conservation problem with metal objects occurs when corrosion processes form a threat to the safety of the object or disfigure its appearance to an unacceptable degree (130,131), many conservation treatments are intended to stabilize the corrosion processes and to remove aesthetically displeasing corrosion cmsts. The latter requkes a great deal of thought and discussion as to when a corrosion layer ceases to be a deskable patina and becomes unacceptable. [Pg.425]

Cellulose nitrate also has widespread use as an adhesive and coating material. Whereas stabilizers are added to products, eg, sodium carbonate as a neutralizer, many conservators are hesitant to use cellulose nitrate materials because of the inherent instabiUty and the dangers to the object from nitric acid, formed when the nitric oxide combines with moisture. [Pg.427]


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See also in sourсe #XX -- [ Pg.78 ]




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