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Themselves

Debye-Hiickel theory The activity coefficient of an electrolyte depends markedly upon concentration. Jn dilute solutions, due to the Coulombic forces of attraction and repulsion, the ions tend to surround themselves with an atmosphere of oppositely charged ions. Debye and Hiickel showed that it was possible to explain the abnormal activity coefficients at least for very dilute solutions of electrolytes. [Pg.125]

Can be coupled in the 4-position with dia-zotized bases to give a series of azo dyestuffs more usually it is first sulphonated to give a valuable series of intermediates for solubilized azo dyestuffs. The nitro-l-naphthols are themselves dyestuffs, e.g. 2,4-dinitro-l-naph-thol ( naphtol yellow ). [Pg.270]

Some nitro-compounds are themselves coloured and can be used as dyestuffs, e.g. picric acid. In this case the nitro-group can be considered to be the chromophore. For aliphatic nitro-compounds see nitroparaffins. [Pg.277]

Ullman reaction The synthesis of diaryls by the condensation of aromatic halides with themselves or other aromatic halides, with the concomitant removal of halogens by a metal, e.g. copper powder thus bromobenzene gives diphenyl. The reaction may be extended to the preparation of diaryl ethers and diaryl thio-ethers by coupling a metal phenolate with an aryl halide. [Pg.411]

Watson s vivid and outspoken account of how he and Crick discovered the structure of DNA (and won themselves a Nobel Prize) - one of the greatest scientific achievements of the century. [Pg.441]

Poiar stationary phases which have a polar moment. These phases interact with the dipoiar moments of poiar components themselves and those components capable of induced polarization such as aromatics. [Pg.21]

Liquid chromatography is preceded by a precipitation of the asphaltenes, then the maltenes are subjected to chromatography. Although the separation between saturated hydrocarbons and aromatics presents very few problems, this is not the case with the separation between aromatics and resins. In fact, resins themselves are very aromatic and are distinguished more by their high heteroatom content (this justifies the terms, polar compounds or N, S, 0 compounds , also used to designate resins). [Pg.83]

As we have shown previously, obtaining both good cold operation characteristics and sufficient cetane numbers constitutes the principal objective for the refiner in the formulation of diesel fuel. To this is added the need for deep desulfurization and, perhaps in the future, limitations placed on the chemical nature of the components themselves, e.g., aromatics content. [Pg.223]

As their name implies, these products are used essentially for jet aircraft they can also be used in stationary turbines, which are themselves adaptable to a large variety of fuels such as natural gas, LPG, diesel fuel, and heating oil. [Pg.225]

The vapor pressure of a crude oil at the wellhead can reach 20 bar. If it were necessary to store and transport it under these conditions, heavy walled equipment would be required. For that, the pressure is reduced (< 1 bar) by separating the high vapor pressure components using a series of pressure reductions (from one to four flash stages) in equipment called separators , which are in fact simple vessels that allow the separation of the two liquid and vapor phases formed downstream of the pressure reduction point. The different components distribute themselves in the two phases in accordance with equilibrium relationships. [Pg.319]

In using the alkylphenols, it is possible to obtain three types of detergents the alkylphenols themselves transformed as salts of calcium, the alkylphenol-sulfides conferring antioxidant properties and finally the alkylphenol-sulfides transformed by action of CO2 into alkylsalicylate-sulfides (Figure 9.9). [Pg.360]

The same procedure may be used to rank the parameters themselves (GRV, N/G, ((>, S, Bg, recovery factor), to indicate which has the greatest influence on the HCIIP or ultimate recovery (UR). [Pg.176]

The end users of CBR systems should in principle be able to maintain the case-bases themselves and use the systems for varying inspection types (within certain limits). Adaptation of neural-network based systems, though possible by end-users, is difficult to be done reliably. Adaptation of rule-based systems usually has to be done by the rule-base designer. [Pg.103]

The major drawback of this identification method, as used to date, is that only a part of the useful information contained into original Bscan image, i.e. segmented Bscan image, is used for defect characterization. Moreover, it requires the availability of defect classification information (i.e. if the defect is volumetric or planar, e.g. a crack or a lack of fusion), which, generally, may be as difficult to obtain as the defect parameters themselves. Therefore, we... [Pg.171]

A nematic liquid crystal cell, based on Merck Licrilite E202, was used in these experiments. The rod like liquid crystal molecules preferentially aligned themselves with each other and to an alignment surface in the liquid crystal device. Any birefringence. An, was given as the difference between the two orthogonal refractive indices. As a consequence, any resulting... [Pg.680]

Electromagnetic earthquake forerunners show themselves like the electromagnetic phenomena, including electromagnetic emission (EME) in a radio frequency range. This emission caused by collective exiting of the set of local mechano-electrical transformers (MET). The excitation mechanism inside the crust is determined by the fact that elastic tension ranges up to the threshold level within the source area. [Pg.914]

The probes themselves could be fitted with a button, like a computer mouse, for clicking when over a grid point. This would allow one-hand operation and make sampling in... [Pg.1016]

Calculated from various theoretical equations some of the sources are themselves compilations rather than original. [Pg.239]

The effect is more than just a matter of pH. As shown in Fig. XV-14, phospholipid monolayers can be expanded at low pH values by the presence of phosphotungstate ions [123], which disrupt the stmctival order in the lipid film [124]. Uranyl ions, by contrast, contract the low-pH expanded phase presumably because of a type of counterion condensation [123]. These effects caution against using these ions as stains in electron microscopy. Clearly the nature of the counterion is very important. It is dramatically so with fatty acids that form an insoluble salt with the ion here quite low concentrations (10 M) of divalent ions lead to the formation of the metal salt unless the pH is quite low. Such films are much more condensed than the fatty-acid monolayers themselves [125-127]. [Pg.557]


See other pages where Themselves is mentioned: [Pg.51]    [Pg.110]    [Pg.267]    [Pg.155]    [Pg.160]    [Pg.180]    [Pg.288]    [Pg.308]    [Pg.318]    [Pg.331]    [Pg.332]    [Pg.341]    [Pg.352]    [Pg.354]    [Pg.381]    [Pg.384]    [Pg.391]    [Pg.411]    [Pg.54]    [Pg.188]    [Pg.190]    [Pg.485]    [Pg.230]    [Pg.187]    [Pg.221]    [Pg.275]    [Pg.543]    [Pg.61]    [Pg.79]    [Pg.101]    [Pg.176]    [Pg.478]   


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