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Clarifier derivative

The concept of temperature derives from a fact of conmron experience, sometimes called the zeroth law of themiodynamics , namely, if tM o systems are each in thermal equilibrium with a third, they are in thermal equilibrium with each other. To clarify this point, consider the tliree systems shown schematically in figure A2.1.1, in which there are diathemiic walls between systems a and y and between systems p and y, but an adiabatic wall between systems a and p. [Pg.324]

The equilibrium problem for a plate is formulated as some variational inequality. In this case equations (3.92)-(3.94) hold, generally speaking, only in the distribution sense. Alongside (3.95), other boundary conditions hold on the boundary F the form of these conditions is clarified in Section 3.3.3. To derive them, we require the existence of a smooth solution to the variational inequality in question. On the other hand, if we assume that a solution to (3.92)-(3.94) is sufficiently smooth, then the variational inequality is a consequence of equations (3.92)-(3.94) and the initial and boundary conditions. All these questions are discussed in Section 3.3.3. In Section 3.3.2 we prove an existence theorem for a solution to the variational equation and in Section 3.3.4 we establish some enhanced regularity properties for the solution near F. ... [Pg.200]

This inequality can be written in the new variables. In order to clarify the structure of the relation obtained in this way, we write down one of the second derivatives of w ... [Pg.287]

Chemical Precipitation. The product of the extraction processes, whether derived from acid or carbonate leach, is a purified uranium solution that may or may not have been upgraded by ion exchange or solvent extraction. The uranium ia such a solution is concentrated by precipitation and must be dried before shipment. Solutions resulting from carbonate leaching are usually precipitated directly from clarified leach Hquors with caustic soda without a concentration step, as shown ia equation 9. [Pg.318]

The main by-products of the Ullmaim condensation are l-aniinoanthraquinone-2-sulfonic acid and l-amino-4-hydroxyanthraquinone-2-sulfonic acid. The choice of copper catalyst affects the selectivity of these by-products. Generally, metal copper powder or copper(I) salt catalyst has a greater reactivity than copper(Il) salts. However, they are likely to yield the reduced product (l-aniinoanthraquinone-2-sulfonic acid). The reaction mechanism has not been estabUshed. It is very difficult to clarify which oxidation state of copper functions as catalyst, since this reaction involves fast redox equiUbria where anthraquinone derivatives and copper compounds are concerned. Some evidence indicates that the catalyst is probably a copper(I) compound (28,29). [Pg.310]

The alkylation reactions of enolate anions of both ketones and esters have been extensively utilized in synthesis. Both very stable enolates, such as those derived from (i-ketoesters, / -diketones, and malonate esters, as well as less stable enolates of monofunctional ketones, esters, nitriles, etc., are reactive. Many aspects of the relationships between reactivity, stereochemistry, and mechanism have been clarified. A starting point for the discussion of these reactions is the structure of the enolates. Because of the delocalized nature of enolates, an electrophile can attack either at oxygen or at carbon. [Pg.435]

Tlie oxo-thione form 241 is taken for 2-mercapto-4-hydroxyimidazoles (Scheme 83) [76AHC(S1), p. 463]. These tautomeric equilibria were clarified by the consideration of models in which some tautomeric forms were blocked. Thus, for S-alkylated 5,5-diphenyl 242 or 5-spirocyclohexyl 243 derivatives, oxo-thiol forms are the major tautomers [73T3565 76AHC(S1), p. 463]. [Pg.245]

The structure of 5-amino-l-thia-2,4-diazoles has been clarified by Goerdeler, Huppertz, and Wember who compared the ultraviolet spectra and basicities of 194 (E, = Me or Ph) and the methylated derivatives 195 and 196, thereby showing that 194 exists in the amino form. This conclusion is supported by polarographic data. ... [Pg.72]

Formula for the chemical potentials have been derived in terms of the formation energy of the four point defects. In the process the conceptual basis for calculating point defect energies in ordered alloys and the dependence of point defect concentrations on them has been clarified. The statistical physics of point defects in ordered alloys has been well described before [13], but the present work represents a generalisation in the sense that it is not dependent on any particular model, such as the Bragg-Williams approach with nearest neighbour bond energies. It is hoped that the results will be of use to theoreticians as well as... [Pg.346]

At R > 400 pm the orientation of the reactants looses its importance and the energy level of the educts is calculated (ethene + nonclassical ethyl cation). For smaller values of R and a the potential energy increases rapidly. At R = 278 pm and a = 68° one finds a saddle point of the potential energy surface lying on the central barrier, which can be connected with the activated complex of the reaction (21). This connection can be derived from a vibration analysis which has already been discussed in part 2.3.3. With the assistance of the above, the movement of atoms during so-called imaginary vibrations can be calculated. It has been attempted in Fig. 14 to clarify the movement of the atoms during this vibration (the size of the components of the movement vector... [Pg.219]

The course of the reaction has not been fully clarified. Hydrolytic and aromatization processes are probably responsible for the formation of colored or fluorescent deriva4 tives (cf. Potassium Hydroxide Reagent). For instance, sevin is converted to a-naphthalkali metal salt of the o-hydroxycinnamic acid pro- duced by hydrolytic cleavage of the pyrone ring is converted from the non-fluorescent cis- to the fluorescent trans-form by the action of long-wavelength UV light (X = 365 nm) [2]. [Pg.202]

The exceeded value for children via the environment from exposure to dioctyltin (356% of the TDI) relates to the consumption of local produce close to a PVC processing plant and largely derives from default values on release to the environment. Further refinement of this exposure assessment is currently under way. Until this is clarified, dioctyltin remains a compound of concern via this exposure route for children. [Pg.39]

The data in animals are insufficient to derive an acute inhalation MRL because serious effects were observed at the lowest dose tested (Hoechst 1983a). No acute oral MRL was derived for the same reason. The available toxicokinetic data are not adequate to predict the behavior of endosulfan across routes of exposure. However, the limited toxicity information available does indicate that similar effects are observed (i.e., death, neurotoxicity) in both animals and humans across all routes of exposure, but the concentrations that cause these effects may not be predictable for all routes. Most of the acute effects of endosulfan have been well characterized following exposure via the inhalation, oral, and dermal routes in experimental animals, and additional information on the acute effects of endosulfan does not appear necessary. However, further well conducted developmental studies may clarify whether this chemical causes adverse developmental effects. [Pg.190]

More recent studies on Co (II) salen and related derivatives are discussed in Section IV(A), and these will clarify and extend the older work just considered, particularly from a structural point of view. [Pg.7]

The most fundamental issues of the structures of heavier group 14 element-centered anionic derivatives R3EM (R = alkyl, aryl, silyl E = Si, Ge, Sn, Pb M = alkali or alkaline earth metals) turned out to be the questions of their aggregation states (monomeric, dimeric, or oligomeric), nature of the E-M bond (covalent or ionic), and configuration of the anionic centers E (tetrahedral, pyramidal, or planar). The most important experimental techniques that are widely used to clarify these questions are NMR spectroscopy and X-ray diffraction analysis. [Pg.93]

To clarify this problem, our approach will be the following first, we shall devote ourselves to finding a formula for K, independently of any of the three existing derivations made for the most general TV-dimensional case then we shall compare our answer to the previously published results. [Pg.140]

The relative stereochemistry of stephadiamine (16) was clarified by X-ray diffraction analysis, using the direct method, and the absolute configuration was solved by the heavy-atom method, using the N-p-bromobenzoyl derivative (6). Stephadiamine (16), a C-norhasubanan alkaloid, is not regarded as a hasubanan congener in the strict sense, but as a new member of oe-amino acid derivatives (6). [Pg.332]

The effectiveness of these parameters is considered to depend heavily on the liquefaction conditions and the characteristics of the coal which is used. The better parameters can possibly be derived from both the amounts of the petrographic components %9 such as inerts ingredients %9 or reactive macerals % and their quality, such as H/C atomic ratio and so on. Consequently, it must be said that much further study is necessary to finally clarify the more comprehensive parameter. [Pg.100]

Exactly this problem was the subject of synthetic experiments carried out by J. Oro et al. (1984), which were intended to clarify the possible formation of these condensation agents. They used simple compounds, such as formaldehyde, acetaldehyde, glyoxal and ammonia as starting materials, and were able to synthesize imidazole as well as its 2- and 4-methyl derivatives. [Pg.153]

The above derivation shows that Jarzynski s identity is an immediate consequence of the Feynman-Kac theorem. This connection has not only theoretical value, but is also useful in practice. First, it forms the basis for an equilibrium thermodynamic analysis of nonequilibrium pulling experiments [3, 15]. Second, it helps in deriving a Jarzynski identity for dynamics using thermostats. Moreover, this derivation clarifies an important aspect trajectories can be thought of as mapping initial conditions (I = 0) to trajectory endpoints, and the Boltzmann factor of the accumulated work reweights that map to give the desired Boltzmann distribution. Finally, it can be easily extended to transformations between steady states [17] in which non-Boltzmann distributions are stationary. [Pg.177]

Another example of a nudibranch, which probably modifies dietary metabolites to obtain more effective allomones, is seen in Aldisa cooperi (= A. sanguinea cooperi) [155]. It elaborates two fish antifeedant bile acids (104,105) that are absent in its prey, the sponge Anthoarcuata graceae, where the main steroid is 4-cholesten-3-one (106). Biosynthetic experiments starting from both labelled mevalonic acid and labelled 4-eholesten-3-one would definitely clarify, whether, the two allomones (104-105) are biosynthetized de novo by the mollusc, or if they are derived from a food source. [Pg.114]


See other pages where Clarifier derivative is mentioned: [Pg.458]    [Pg.222]    [Pg.124]    [Pg.442]    [Pg.159]    [Pg.326]    [Pg.125]    [Pg.264]    [Pg.229]    [Pg.87]    [Pg.16]    [Pg.405]    [Pg.12]    [Pg.6]    [Pg.623]    [Pg.39]    [Pg.52]    [Pg.260]    [Pg.572]    [Pg.285]    [Pg.129]    [Pg.2]    [Pg.40]    [Pg.65]    [Pg.55]    [Pg.273]    [Pg.89]    [Pg.277]    [Pg.357]    [Pg.8]   
See also in sourсe #XX -- [ Pg.27 , Pg.81 , Pg.130 , Pg.210 ]




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