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Functional derivatives of

Functional derivatives of polyethylene, particularly poly(vinyl alcohol) and poly(acryLic acid) and derivatives, have received attention because of their water-solubility and disposal iato the aqueous environment. Poly(vinyl alcohol) is used ia a wide variety of appHcations, including textiles, paper, plastic films, etc, and poly(acryLic acid) is widely used ia detergents as a builder, a super-absorbent for diapers and feminine hygiene products, for water treatment, ia thickeners, as pigment dispersant, etc (see Vinyl polymers, vinyl alcohol polymers). [Pg.479]

Carboxjiates with a fiuorinated alkyl chain ate marketed by the 3M/Industrial Chemical Products Company under the trade name Fluotad surfactants. They also include other functional derivatives of fiuorinated and perfluorinated alkyl chains. Replacement of hydrogens on the hydrophobe by fluorine atoms leads to surfactant molecules of unusually low surface tension. This property imparts excellent leveling effectiveness. [Pg.238]

To determine the position of the tricritical point and the structure of the ordered phases stable below the bifurcation we analyze the asymptotic form of Qeff for e 0. At local minima the functional derivative of Qeff with respect to all the OPs vanishes. From this condition and from (45), (58), (47), and (64) we find that at the metastable states... [Pg.725]

The application of spectroscopic methods to the study of tautom-erism proved especially fruitful. The tautomerism of hydroxy and amino derivatives of isoxazole is of great interest to the chemistry of isoxazole this subject, as well as the tautomerism of functional derivatives of other five-membered heterocycles, has been reviewed by Katritzky and Lagowski. We shall therefore only... [Pg.380]

There are some problems associated with the use of functional derivatives of carboxylic acids. Long-chain acid anhydrides are not commercially available, and one half of the acylation reagent is not utilized. Acyl chlorides require the use of tertiary base catalysts, whose double role has been explained before. Some of the intermediate acyl ammonium compounds formed are, however, insoluble in the solvent system. Examples include RCO - N+EtsCL in LiCl/DMAc, where RCO refers to the propionyl, hexanoyl, and stearoyl moiety, respectively. Hexanoyl- and stearoyl-pyridinium chlorides are also insoluble in the same solvent system [185]. [Pg.131]

Also other examples, some from functional derivatives of quinoxaline aldehydes 2,202,231,273,310,590,909,932... [Pg.298]

Note that in all current implementations of TDDFT the so-called adiabatic approximation is employed. Here, the time-dependent exchange-correlation potential that occurs in the corresponding time-dependent Kohn-Sham equations and which is rigorously defined as the functional derivative of the exchange-correlation action Axc[p] with respect to the time-dependent electron-density is approximated as the functional derivative of the standard, time-independent Exc with respect to the charge density at time t, i. e.,... [Pg.81]

While the behavior of the exchange-correlation potential Vxc (recall from equation (5-16) that the exchange-correlation potential Vxc is defined as the functional derivative of the... [Pg.105]

Note that the operator fKS differs from the Fock operator f that we introduced in Section 1.3 in connection with the Hartree-Fock scheme only in the way the exchange and correlation potentials are treated. In the former, the non-classical contributions are expressed via the - in its exact form unknown - exchange-correlation potential Vxc, the functional derivative of Exc with respect to the charge density. In the latter, correlation is neglected... [Pg.109]

First, the self-energy operator is replaced by a local exchange-correlation potential, which is given by the functional derivative of the exchange-correlation energy with respect to the electron density ... [Pg.84]

The addition-elimination reaction of hetero-atom-substituted nitroalkenes provides functionalized derivatives of unsaturated nitro compounds.26 Nitroenamines are generally prepared from a-nitro ketones and amines (see Chapter 5 regarding acylation of nitro compounds).26... [Pg.76]

Barboiu, M., Hovnanian, N., Luca, C., Popescu, G. and Cot, L. (1998) Functionalized derivatives of benzocrown-ethers, III, New macrocydic derivatives containing chiral and linear lateral amino-acid moieties. European Journal of Organic Chemistry, 1705—1708. [Pg.335]

Of the further functional derivatives of cyclopropenones in the diphenyl series, the oxime115,121) and several hydrazones115) (e.g. 158/159), and a2ines (e.g. 760U5)), are easily available from the ethoxy cation 75 and hydroxylamine, hydrazines, and hydrazones, respectively. Sometimes oximation of cyclopropenones produces unexpected results (see later and Ref.42 ). [Pg.33]

There are several ways of obtaining functionals for nonideal systems. In most cases the free energy functional is expressed as the sum of an ideal gas term, a hard-sphere term, and a term due to attractive forces. Below, I present a scheme by which approximate expression for the free energy functional may be obtained. This approach relies on the relationship between the free energy functional and the direct correlation function. Because the direct correlation functions are defined through functional derivatives of the excess free energy functional, that is,... [Pg.118]

Here A(r — r ) is the Onsager coefficient that specifies the transport properties of the considered system at a certain timescale and lengthscale, and which is nonlocal in general. The local chemical potential difference p(r) can be found in a standard way as a functional derivative of the coarse-grained free energy functional F [<()] ... [Pg.178]


See other pages where Functional derivatives of is mentioned: [Pg.26]    [Pg.236]    [Pg.82]    [Pg.213]    [Pg.220]    [Pg.350]    [Pg.171]    [Pg.125]    [Pg.299]    [Pg.155]    [Pg.228]    [Pg.232]    [Pg.63]    [Pg.106]    [Pg.121]    [Pg.93]    [Pg.261]    [Pg.500]    [Pg.1056]    [Pg.157]    [Pg.167]    [Pg.168]    [Pg.327]    [Pg.86]    [Pg.458]    [Pg.482]    [Pg.489]    [Pg.220]    [Pg.116]    [Pg.78]   
See also in sourсe #XX -- [ Pg.817 , Pg.818 , Pg.819 ]




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Calculating Derivatives of General Functions

Derivation of P(E) Functions

Derivation of the Nonnalized Transfer Function

Derivation of the Transfer Function

Derivative Continuity of the Basis Function at its Ends

Derivative function

Derivative of an Analytic Function

Derivatives of arsabenzene possessing a functional group

Derivatives of common functions

Derivatives of function

Derivatives of the Molecular Mechanics Energy Function

Function derived

Functional derivatives of carbonic acid

Functional derivatives, of carboxylic acids

Interconversion of functional derivatives

Olefins and Functional Derivatives in the Presence of Alcohols

Olefins and Functional Derivatives in the Presence of Carboxylic Acids, Thiols, Amines or Hydrogen Chloride

Olefins and Functional Derivatives in the Presence of Water

Partial derivative of function

Preparation of Functionalized Alkenylzirconocene Derivatives

Pressure and Temperature Derivatives of the Functions

Statistical derivation of the NVT partition function

Synthesis and Reactions of Functionalized Alkyl Boron Derivates

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