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Nonreactive

The total number of stoichiometric (nonreacted) components is designated by m there are m(m+l)/2 equations of the form given by Equations (33) and (34). [Pg.134]

Stratt R M and Maroncelli M 1996 Nonreactive dynamics in solution the emerging molecular view of solvation dynamics and vibrational relaxation J. Phys. Chem. 100 12 981... [Pg.897]

Although the Sclirodinger equation associated witii the A + BC reactive collision has the same fonn as for the nonreactive scattering problem that we considered previously, it cannot he. solved by the coupled-channel expansion used then, as the reagent vibrational basis functions caimot directly describe the product region (for an expansion in a finite number of tenns). So instead we need to use alternative schemes of which there are many. [Pg.975]

This equation may be solved by the same methods as used with the nonreactive coupled-channel equations (discussed later in section A3.11.4.2). Flowever, because F(p, p) changes rapidly with p, it is desirable to periodically change the expansion basis set ip. To do this we divide the range of p to be integrated into sectors and within each sector choose a (usually the midpoint) to define local eigenfimctions. The coiipled-chaimel equations just given then apply withm each sector, but at sector boundaries we change basis sets. Let y and 2 be the associated with adjacent sectors. Then, at the sector boundary p we require... [Pg.976]

At this point, it is important to note that as the potential energy surfaces are even in the vibrational coordinate (r), the same parity, that is, even even and odd odd transitions should be allowed both for nonreactive and reactive cases but due to the conical intersection, the diabatic calculations indicate that the allowed transition for the reactive case ate odd even and even odd whereas in the case of nomeactive transitions even even and odd odd remain allowed. [Pg.51]

In this chapter, we discussed the significance of the GP effect in chemical reactions, that is, the influence of the upper electronic state(s) on the reactive and nonreactive transition probabilities of the ground adiabatic state. In order to include this effect, the ordinary BO equations are extended either by using a HLH phase or by deriving them from first principles. Considering the HLH phase due to the presence of a conical intersection between the ground and the first excited state, the general fomi of the vector potential, hence the effective... [Pg.79]

Another type of demasking involves formation of new complexes or other compounds that are more stable than the masked species. For example, boric acid is used to demask fluoride complexes of tin(IV) and molybdenum(VI). Formaldehyde is often used to remove the masking action of cyanide ions by converting the masking agent to a nonreacting species through the reaction ... [Pg.1170]

Nonreactive additive flame retardants dominate the flexible urethane foam field. However, auto seating appHcations exist, particularly in Europe, for a reactive polyol for flexible foams, Hoechst-Celanese ExoHt 413, a polyol mixture containing 13% P and 19.5% Cl. The patent beHeved to describe it (114) shows a reaction of ethylene oxide and a prereacted product of tris(2-chloroethyl) phosphate and polyphosphoric acid. An advantage of the reactive flame retardant is avoidance of windshield fogging, which can be caused by vapors from the more volatile additive flame retardants. [Pg.479]

Reactant molecules are able to withstand more fluorine coUisions, as they become more highly fluorinated, without decomposition because some sites are stericaUy protected, ie, coUisions at carbon—fluorine sites are obviously nonreactive. The fluorine concentration may therefore be increased as the... [Pg.275]

Direct Fluorination. This is a more recently developed method for the synthesis of perfluorinated compounds. In this process, fluorine gas is passed through a solution or suspension of the reactant in a nonreactive solvent such as trichlorotrifluoroethane (CFC-113). Sodium fluoride may also be present in the reaction medium to remove the coproduct hydrogen fluoride. There has been enormous interest in this area since the early 1980s resulting in numerous journal pubHcations and patents (7—9) (see Fluorine compounds, organic-direct fluorination). Direct fluorination is especially useful for the preparation of perfluoroethers. [Pg.298]

Petroleum resins are low molecular weight thermoplastic hydrocarbon resins synthesized from steam cracked petroleum distillates. These resins are differentiated from higher molecular weight polymers such as polyethylene and polypropylene, which are produced from essentially pure monomers. Petroleum resin feedstocks are composed of various reactive and nonreactive aliphatic and aromatic components. The resins are usually classified as C-5... [Pg.351]

Pentanes are only slightly toxic. Because of their high volatihties and, consequently, their low flash points, they are highly flammable. Pentanes are classified as nonreactive, ie, they do not react with fire-fighting agents. The fire ha2ard properties for pentanes are Hsted in Table 8 (38). [Pg.404]

Quats are usually moderately soluble ia water, but this varies widely owiag to the range of groups bonded to the nitrogen. They are fundamentally nonreactive but act as surface—active cations. Compatibility with anionic detergents and activity ia the presence of hard water have been claimed for some quats (19). [Pg.95]

More convenient is the use of aryl a2ides which are readily converted into isocyanates upon heating in nonreactive solvents via the loss of nitrogen. The latter method is useful for the synthesis of isocyanates with additional substituents which could not be prepared with phosgene (20). [Pg.448]

Solvent extraction using nonreactive Hquids, such as C - or C -alcohols, benzene, or benzene-alcohol mixtures, yields generally 5—20% wax or bitumen (15). The yield and composition of the product are determined primarily by the petrologic character of the coal, not its degree of coalification. Montan wax is extracted from suitable coals for a variety of purposes. [Pg.151]

The free maleic acid content in maleic anhydride is determined by direct potentiometric titration (166). The procedure involves the use of a tertiary amine, A/-ethylpipetidine [766-09-6J, as a titrant. A tertiary amine is chosen as a titrant since it is nonreactive with anhydrides (166,167). The titration is conducted in an anhydrous solvent system. Only one of the carboxyhc acid groups is titrated by this procedure. The second hydrogen s dissociation constant is too weak to titrate (166). This test method is not only used to determine the latent acid content in refined maleic acid, but also as a measure of the sample exposure to moisture during shipping. [Pg.459]

Chemical Properties and Reactivity. LLDPE is a saturated branched hydrocarbon. The most reactive parts of LLDPE molecules are the tertiary CH bonds in branches and the double bonds at chain ends. Although LLDPE is nonreactive with both inorganic and organic acids, it can form sulfo-compounds in concentrated solutions of H2SO4 (>70%) at elevated temperatures and can also be nitrated with concentrated HNO. LLDPE is also stable in alkaline and salt solutions. At room temperature, LLDPE resins are not soluble in any known solvent (except for those fractions with the highest branching contents) at temperatures above 80—100°C, however, the resins can be dissolved in various aromatic, aUphatic, and halogenated hydrocarbons such as xylenes, tetralin, decalin, and chlorobenzenes. [Pg.395]


See other pages where Nonreactive is mentioned: [Pg.900]    [Pg.1904]    [Pg.2425]    [Pg.2638]    [Pg.2807]    [Pg.42]    [Pg.44]    [Pg.48]    [Pg.48]    [Pg.51]    [Pg.81]    [Pg.234]    [Pg.687]    [Pg.87]    [Pg.88]    [Pg.88]    [Pg.282]    [Pg.292]    [Pg.349]    [Pg.314]    [Pg.460]    [Pg.474]    [Pg.367]    [Pg.353]    [Pg.429]    [Pg.431]    [Pg.79]    [Pg.80]    [Pg.493]    [Pg.494]    [Pg.455]   
See also in sourсe #XX -- [ Pg.218 , Pg.222 , Pg.230 , Pg.234 ]




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Additives nonreactive liquid

Adhesives, applications nonreactive

Alkanes nonreactivity

Balances independent, nonreactive system

Balances on Nonreactive Processes

Cofeed (FBR) vs. Distributed Dosing of Reactants (PBMR) Nonreactive Conditions

Collision reaction, nonreactive trajectories

Collisions, nonreactive

Combination of reactive and nonreactive sections in a RD column

Cooling nonreactive

Determination of Change in Enthalpy for Nonreacting Species and Mixtures

Diluents nonreactive

Energy Balances on Single-Phase Nonreactive Processes

Ethane nonreactivity

Fundamentals of Material Balance (Nonreactive Systems)

Mass transfer coefficients nonreactive measurement

Mechanisms Using Nonreactive Gases and KED

Modification nonreactive

Molten salts nonreactive

Nondiluent, Nonreactive

Nonreacting

Nonreacting Multistage Isothermal Systems

Nonreacting Systems

Nonreacting component

Nonreacting mixture

Nonreaction node

Nonreactive Nonaqueous Dispersants

Nonreactive Processes

Nonreactive binary mixtures

Nonreactive cationic surfactants

Nonreactive complexes

Nonreactive gas mixture

Nonreactive gases

Nonreactive ligand concentration

Nonreactive measurement

Nonreactive polyamides

Nonreactive resins

Nonreactive scattering amplitudes

Nonreactive trajectories

Phase Separation Kinetics in Nonreactive Polymer Systems

Phase Transition from Photochemically Nonreactive Inclusion Complexes to Reactive Ones

Rotational excitation, nonreactive

Scattering nonreactive

Single-phase flows nonreacting

System, Nonreactive

Ternary Polymer Addition (Nonreactive)

The Laws for Closed Nonreacting Systems

The Laws for Open Nonreacting Systems

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