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Competition between

As referred to above, most of the modules involve the intervention of a third party, the so-called notified bodies. These bodies are designated by Member States as being competent to carry out the certification tasks for which they are notified. As a precondition for their notification they must fulfil the minimum criteria which are set out in the relevant directives. These conditions vary from independence, impartiality and professional integrity, to technical competence, possession of or access to necessary facilities and to liability insurance. Once notified, the Commission publishes a list of all notified bodies in the Official Journal, It is worth noting that there is free competition between notified bodies and that manufacturers can make their own choice from all notified bodies notified within the European Union. [Pg.939]

Various functional forms for / have been proposed either as a result of empirical observation or in terms of specific models. A particularly important example of the latter is that known as the Langmuir adsorption equation [2]. By analogy with the derivation for gas adsorption (see Section XVII-3), the Langmuir model assumes the surface to consist of adsorption sites, each having an area a. All adsorbed species interact only with a site and not with each other, and adsorption is thus limited to a monolayer. Related lattice models reduce to the Langmuir model under these assumptions [3,4]. In the case of adsorption from solution, however, it seems more plausible to consider an alternative phrasing of the model. Adsorption is still limited to a monolayer, but this layer is now regarded as an ideal two-dimensional solution of equal-size solute and solvent molecules of area a. Thus lateral interactions, absent in the site picture, cancel out in the ideal solution however, in the first version is a properly of the solid lattice, while in the second it is a properly of the adsorbed species. Both models attribute differences in adsorption behavior entirely to differences in adsorbate-solid interactions. Both present adsorption as a competition between solute and solvent. [Pg.391]

For very fast reactions, the competition between geminate recombmation of a pair of initially fomied reactants and its escape from the connnon solvent cage is an important phenomenon in condensed-phase kinetics that has received considerable attention botli theoretically and experimentally. An extremely well studied example is the... [Pg.860]

Straub J E and Berne B J 1986 Energy diffusion in many dimensional Markovian systems the consequences of the competition between inter- and intra-molecular vibrational energy transfer J. Chem. Phys. 85 2999 Straub J E, Borkovec M and Berne B J 1987 Numerical simulation of rate constants for a two degree of freedom system in the weak collision limit J. Chem. Phys. 86 4296... [Pg.897]

Gershinsky G and Berne B J 1999 The rate constant for activated barrier crossing the competition between IVR and energy transfer to the bath J. Chem. Phys. 110 1053... [Pg.897]

From SCRP spectra one can always identify the sign of the exchange or dipolar interaction by direct exammation of the phase of the polarization. Often it is possible to quantify the absolute magnitude of D or J by computer simulation. The shape of SCRP spectra are very sensitive to dynamics, so temperature and viscosity dependencies are infonnative when knowledge of relaxation rates of competition between RPM and SCRP mechanisms is desired. Much use of SCRP theory has been made in the field of photosynthesis, where stnicture/fiinction relationships in reaction centres have been connected to their spin physics in considerable detail [, Mj. [Pg.1617]

C3.2.2.12 COMPETITION BETWEEN INNER SPHERE AND OUTER SPHERE NUCLEAR POLARIZATION DYNAMICS... [Pg.2986]

Section 8 13 When nucleophilic substitution is used for synthesis the competition between substitution and elimination must be favorable However the normal reaction of a secondary alkyl halide with a base as strong or stronger than hydroxide is elimination (E2) Substitution by the Sn2 mechanism predominates only when the base is weaker than hydroxide or the alkyl halide is primary Elimination predominates when tertiary alkyl halides react with any anion... [Pg.355]

A further consequence of the high temperatures is that much of the sample is simply evaporated without producing isolated positive ions. There is a competition between formation of positive ions and the evaporation of neutral particles. Since the mass spectrometer examines only isolated charged species, it is important for maximum sensitivity that the ratio of positive ions to neutrals be as large as possible. Equation 7.1 governing this ratio is given here. [Pg.46]

Since = AH /ASf, the observed behavior of this series of polymers may be understood as a competition between these effects. For the smaller substituents, the effect on AH dominates and decreases with bulk. For larger substituents, the effect of AS dominates and increases with bulk. [Pg.211]

This has the advantage that the expressions for the adsotbed-phase concentration ate simple and expHcit, and, as in the Langmuir expression, the effect of competition between sorbates is accounted for. However, the expression does not reduce to Henry s law in the low concentration limit and therefore violates the requirements of thermodynamic consistency. Whereas it may be useful as a basis for the correlation of experimental data, it should be treated with caution and should not be used as a basis for extrapolation beyond the experimental range. [Pg.256]

Fig. 3. Two-dimensional schematic illustrating the distribution of Hquid between the Plateau borders and the films separating three adjacent gas bubbles. The radius of curvature r of the interface at the Plateau border depends on the Hquid content and the competition between surface tension and interfacial forces, (a) Flat films and highly curved borders occur for dry foams with strong interfacial forces, (b) Nearly spherical bubbles occur for wet foams where... Fig. 3. Two-dimensional schematic illustrating the distribution of Hquid between the Plateau borders and the films separating three adjacent gas bubbles. The radius of curvature r of the interface at the Plateau border depends on the Hquid content and the competition between surface tension and interfacial forces, (a) Flat films and highly curved borders occur for dry foams with strong interfacial forces, (b) Nearly spherical bubbles occur for wet foams where...
Aldehydes are important products at all pressures, but at low pressures, acids are not. Carbon monoxide is an important low pressure product and declines with increasing pressure as acids increase. This is evidence for competition between reaction sequence 18—20 and reaction 21. Increasing pressure favors retention of the parent carbon skeleton, in concordance with the reversibiUty of reaction 2. Propylene becomes an insignificant product as the pressure is increased and the temperature is lowered. Both acetone and isopropyl alcohol initially increase as pressure is raised, but acetone passes through a maximum. This increase in the alcohoLcarbonyl ratio is similar to the response of the methanoLformaldehyde ratio when pressure is increased in methane oxidation. [Pg.341]

In the case of Co—Cr having perpendicular anisotropy there is, in principle, a competition between the uniaxial anisotropy of a hexagonal stmcture and the demagnetizing energy of the thin film. In the case of magnetically separated Co—Cr columns (particulate morphology) then also the shape anisotropy contributes to the perpendicular anisotropy. [Pg.174]

Knowledge of photoiaduced electroa-transfer dyaamics is important to technological appUcations. The quantum efficiency, ( ), ie, the number of chemical events per number of photons absorbed of the desired electron-transfer photoreaction, reflects the competition between rate of the electron-transfer process, eg, from Z7, and the radiative and radiationless decay of the excited state, reflected ia the lifetime, T, of ZA ia abseace ofM. Thus,... [Pg.390]

In the case of hyperphenylalaninaemia, which occurs ia phenylketonuria because of a congenital absence of phenylalanine hydroxylase, the observed phenylalanine inhibition of proteia synthesis may result from competition between T.-phenylalanine and L-methionine for methionyl-/RNA. Patients sufferiag from maple symp urine disease, an inborn lack of branched chain oxo acid decarboxylase, are mentally retarded unless the condition is treated early enough. It is possible that the high level of branched-chain amino acids inhibits uptake of L-tryptophan and L-tyrosiae iato the brain. Brain iajury of mice within ten days after thek bkth was reported as a result of hypodermic kijections of monosodium glutamate (MSG) (0.5—4 g/kg). However, the FDA concluded that MSG is a safe kigredient, because mice are bom with underdeveloped brains regardless of MSG kijections (106). [Pg.283]

Other specific discovery assays have been used such as differential inhibition of a vancomycin resistant S. aureus strain and its susceptible parent, and an assay based on antagonism of the antibacterial activity by N,A/-diacetyl-L-Lys-D-Ala-D-Ala [24570-39-6] a tripeptide analogue of the dalbaheptides receptor. AppHcation of this latter test to 1936 cultures (90) led to the isolation of 42 dalbaheptides, six of which, including kibdelin (Table 3), parvodicin (Table 3), and actinoidin A2 (68) were novel. A colorimetric assay based on competition between horseradish peroxidase bound teicoplanin and the... [Pg.535]

Physical properties of isopropyl alcohol are characteristic of polar compounds because of the presence of the polar hydroxyl, —OH, group. Isopropyl alcohol is completely miscible ia water and readily soluble ia a number of common organic solvents such as acids, esters, and ketones. It has solubiUty properties similar to those of ethyl alcohol (qv). There is a competition between these two products for many solvent appHcations. Isopropyl alcohol has a slight, pleasant odor resembling a mixture of ethyl alcohol and acetone, but unlike ethyl alcohol, isopropyl alcohol has a bitter, unpotable taste. [Pg.104]

Radioisotope dilution assays are based on the principle of competition between radioactive labeled ( Co) vitamin B 2 and cobalamins extracted from matrices for binding sites on the intrinsic factor (a glycoprotein). Binding is in proportion to the concentration of the radioactive and nonradio active B 2 with the concentration of intrinsic factor as the limiting factor. Free cobalamins are separated from those bound on the intrinsic factor by absorption... [Pg.114]

Fiber-reactive dye is also hydrolyzed by reaction with free OH ions in the aqueous phase. This is a nonreversible reaction and so active dye is lost from the system. Hydrolysis of active dye can take place both in the dyebath and on the fiber, although in the latter case there is a competition between the reactions with free hydroxyl ions and those with ionized ceUulose sites. The hydrolyzed dye estabHshes its own equUibrium between dyebath and fiber which could be different from the active dye because the hydrolyzed dye has different chemical potentials in the two phases. The various reactions taking place can be summarized as in Figure 2. [Pg.354]

Fig. 13. Two-component development involving competition between electrostatic and adhesive forces, where + outside and beneath the large circles represents the positively charged toner and the large circles containing negative signs represent carrier beads. Fig. 13. Two-component development involving competition between electrostatic and adhesive forces, where + outside and beneath the large circles represents the positively charged toner and the large circles containing negative signs represent carrier beads.
The reactivities of 1-methylpyrazole (33) and pyrazole (29) are similar and so are the corresponding charges. The competition between C-4 and C-4 in 1-phenylpyrazole depends on the electrophile and on the experimental conditions (Section 4.04.2.3.10(i)). Thus in an acidic medium the reaction takes place on the conjugate acid (34) and considering the calculated charge densities the attack on C-4 would always be favoured. [Pg.174]


See other pages where Competition between is mentioned: [Pg.817]    [Pg.1191]    [Pg.1552]    [Pg.2808]    [Pg.2935]    [Pg.2998]    [Pg.64]    [Pg.65]    [Pg.131]    [Pg.204]    [Pg.139]    [Pg.28]    [Pg.432]    [Pg.429]    [Pg.400]    [Pg.269]    [Pg.467]    [Pg.334]    [Pg.487]    [Pg.64]    [Pg.527]    [Pg.236]    [Pg.537]    [Pg.540]    [Pg.540]    [Pg.99]    [Pg.450]    [Pg.226]    [Pg.493]   


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