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TEMP UNCHANGED. 8IJS2 NOT CALLED. SECOND VIRIAL... [Pg.266]

Most processes are catalyzed where catalysts for the reaction are known. The choice of catalyst is crucially important. Catalysts increase the rate of reaction but are unchanged in quantity and chemical composition at the end of the reaction. If the catalyst is used to accelerate a reversible reaction, it does not by itself alter the position of the equilibrium. When systems of multiple reactions are involved, the catalyst may have different effects on the rates of the different reactions. This allows catalysts to be developed which increase the rate of the desired reactions relative to the undesired reactions. Hence the choice of catalyst can have a major influence on selectivity. [Pg.46]

The algorithm may calculate Qnmia and Qcmm to be unchanged. In this case, the designer knows that the match will not penalize the design in terms of increased utility usage. [Pg.386]

Historically an earth was a non-metallic substance, nearly insoluble in water and unchanged on heating. The alkaline earth oxides, e.g. CaO, have an alkaline reaction in addition to being clearly earths . [Pg.20]

It is prepared by the direct chlorination of toluene in the presence of PClj. It is purified by fractionation from the unchanged toluene and the higher chlorinated products. It is used for benzylating amines and for preparing benzyl alcohol. [Pg.57]

In theory, the catalyst can be recovered chemically unchanged at the end of the reaction, although it may be changed physically. [Pg.85]

Simple stable carbonyls, except V(CO)o, have an electronic configuration corresponding to the next noble gas. Carbonyl groups can be substituted by other unchanged ligands (e.g. [Pg.256]

The phthalocyanine molecule is remarkably stable to heat and chemical reagents. The metal-free and heavy metal compounds sublime practically unchanged at 550-580 C. [Pg.312]

The basic characters from which the notations are constructed comprise the upper-case letters A-Z of the alphabet, the numerals zero (symbolized 0) to nine (0-9), three punctuation marks hyphen (-), ampersand ( ) and oblique (/) and a blank space. Many of the normal atomic symbols such as B, F, P, 1, etc., are also employed unchanged but frequently occurring important elements and groups are assigned a single letter notation (e.g. chlorine sG ... [Pg.426]

Alkanes from CH to C4gFlg2 typically appear in crude oil, and represent up to 20% of the oil by volume. The alkanes are largely chemically inert (hence the name paraffins, meaning little affinity), owing to the fact that the carbon bonds are fully saturated and therefore cannot be broken to form new bonds with other atoms. This probably explains why they remain unchanged over long periods of geological time, despite their exposure to elevated temperatures and pressures. [Pg.91]

In the above example, where the ultimate recovery remains unchanged throughout the field life, the capital allowance rate remains a constant factor of 700/250 = 2.8/bbl. [Pg.312]

Residual austenite is a steel structure which during cooling at martensite transformation temperature is not completely converted into martensite and remains unchanged at room temperature together with martensite. [Pg.18]

There are three changable sensor units for the MH-24/64 magnetic head as like as for MH-24. The units must be changed when rope diameter changes more than two times. The sensor units of the MH-40 and MH-54 are unchangable. So the MH-40 and MH-64 heads are more releable having no connectors for this. [Pg.336]

The effect of a long axial rectangular emerging defect of width e and of depth h is to increase the section Sa between the solenoid and the tube value of AS = eh. The induction in the space between the solenoid and the external surface of the tube and inside of tube remains unchanged. [Pg.353]

This effect assumes importance only at very small radii, but it has some applications in the treatment of nucleation theory where the excess surface energy of small clusters is involved (see Section IX-2). An intrinsic difficulty with equations such as 111-20 is that the treatment, if not modelistic and hence partly empirical, assumes a continuous medium, yet the effect does not become important until curvature comparable to molecular dimensions is reached. Fisher and Israelachvili [24] measured the force due to the Laplace pressure for a pendular ring of liquid between crossed mica cylinders and concluded that for several organic liquids the effective surface tension remained unchanged... [Pg.54]

We will use the superscript a to denote surface quantities calculated on the preceding assumption that the bulk phases continue unchanged to an assumed mathematical dividing surface. For an arbitrary set of variations from equilibrium. [Pg.58]

As is made evident in the next section, there is no sharp dividing line between these two types of adsorption, although the extremes are easily distinguishable. It is true that most of the experimental work has tended to cluster at these extremes, but this is more a reflection of practical interests and of human nature than of anything else. At any rate, although this chapter is ostensibly devoted to physical adsorption, much of the material can be applied to chemisorption as well. For the moment, we do assume that the adsorption process is reversible in the sense that equilibrium is reached and that on desorption the adsorbate is recovered unchanged. [Pg.601]

Heterogeneous photochemical reactions fall in the general category of photochemistry—often specific adsorbate excited states are involved (see, e.g.. Ref. 318.) Photodissociation processes may lead to reactive radical or other species electronic excited states may be produced that have their own chemistry so that there is specificity of reaction. The term photocatalysis has been used but can be stigmatized as an oxymoron light cannot be a catalyst—it is not recovered unchanged. [Pg.738]

The analogous coupling between the antisyimnetric stretch and bend is forbidden in the H2O Hamiltonian because of syimnetry.) The 2 1 resonance is known as a Femii resonance after its introduction [ ] in molecular spectroscopy. The 2 1 resonance is often very prominent in spectra, especially between stretch and bend modes, which often have approximate 2 1 frequency ratios. The 2 1 couplmg leaves unchanged as a poly ad number the sum ... [Pg.70]

Expressing (k) is complicated by the fact that k is not unique. In the Kronig-Penney model, if one replaced k by k + lTil a + b), the energy remained unchanged. In tluee dimensions k is known only to within a reciprocal lattice vector, G. One can define a set of reciprocal vectors, given by... [Pg.106]

It is well known that the trace of a square matrix (i.e., the sum of its diagonal elements) is unchanged by a similarity transfonnation. If we define the traces... [Pg.149]

Much surface work is concerned with the local atomic structure associated with a single domain. Some surfaces are essentially bulk-temiinated, i.e. the atomic positions are basically unchanged from those of the bulk as if the atomic bonds in the crystal were simply cut. More coimnon, however, are deviations from the bulk atomic structure. These structural adjustments can be classified as either relaxations or reconstructions. To illustrate the various classifications of surface structures, figure A1.7.3(a ) shows a side-view of a bulk-temiinated surface, figure A1.7.3(b) shows an oscillatory relaxation and figure A1.7.3(c) shows a reconstructed surface. [Pg.287]

Obviously die first law is not all there is to the structure of themiodynamics, since some adiabatic changes occur spontaneously while the reverse process never occurs. An aspect of the second law is that a state fimction, the entropy S, is found that increases in a spontaneous adiabatic process and remains unchanged in a reversible adiabatic process it caimot decrease in any adiabatic process. [Pg.333]

Equation (A2.1.23) can be mtegrated by the following trick One keeps T, p, and all the chemical potentials p. constant and increases the number of moles n. of each species by an amount n. d where d is the same fractional increment for each. Obviously one is increasing the size of the system by a factor (1 + dQ, increasing all the extensive properties U, S, V, nl) by this factor and leaving the relative compositions (as measured by the mole fractions) and all other intensive properties unchanged. Therefore, d.S =. S d, V=V d, dn. = n. d, etc, and... [Pg.344]


See other pages where Unchanges is mentioned: [Pg.256]    [Pg.266]    [Pg.311]    [Pg.343]    [Pg.362]    [Pg.9]    [Pg.127]    [Pg.305]    [Pg.311]    [Pg.339]    [Pg.272]    [Pg.730]    [Pg.16]    [Pg.178]    [Pg.801]    [Pg.66]    [Pg.137]    [Pg.143]    [Pg.145]    [Pg.147]    [Pg.162]    [Pg.162]    [Pg.257]    [Pg.314]    [Pg.338]    [Pg.343]    [Pg.518]   
See also in sourсe #XX -- [ Pg.67 ]




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Golden Rules Remain Unchanged

Porous Solids of Unchanging Overall Sizes

Shrinking Core Model for Spherical Particles of Unchanging Size

Turnover frequencies unchanged with

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