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Another common sentence error involves a pronoun following the word than. Because the than + (pro)noun construction requires a verb (even if that verb is not articulated), you must use the subjective form of the pronoun I am taller than he [is]. [Pg.19]

You ll probably find at least one multiple-choice question that tests your ability to differentiate between who and whom. Who is the subjective form, and whom is the objective. If you re unclear about which to use, substitute the words he and him for who or whom. If he is correct, you need who (both subjective case) and if him is correct, you need whom (both objective case). Here s an example ... [Pg.20]

This endothermic reaction requires an expensive fired heater as reactor and several subsequent steps if it is desired to lower the H2/CO ratio below 3. A review of this subject forms the introduction to an interesting article by Malleus et al. (157). [Pg.376]

An investigation of several alternative measures based on direct curve comparisons was undertaken by Poll and McLean (2001). For example, for a cross-over trial they considered the following measure for each subject formed by a weighted sum of relative bioavailabilities over the measurement times i ... [Pg.367]

Extensive advances and improvements have been made in the area of sample introduction for ICP-MS and this subject forms a large part of this text. The currently available liquid and solid sampling systems, from nebulisers and spray chambers to electrothermal vaporisation and laser ablation, are described and discussed in detail herein. [Pg.495]

Except in the United Slates of America, this book is sold subject to the condition that it shall not, by way of trade or otherwise, be lent, re-sold, hired out, or otherwise circulated without the publisher s prior consent in any form of binding or cover other than that in which it is published and without a similar condition including this condition being imposed on the subsequent purchaser... [Pg.4]

When subjected to an electron bombardment whose energy level is much higher than that of hydrocarbon covalent bonds (about 10 eV), a molecule of mass A/loses an electron and forms the molecular ion, the bonds break and produce an entirely new series of ions or fragments . Taken together, the fragments relative intensities constitute a constant for the molecule and can serve to identify it this is the basis of qualitative analysis. [Pg.48]

If oil and water are mixed as an emulsion, dehydration becomes much more difficult. Emulsions can form as oil-in-water or water-in-oil if mixed production streams are subjected to severe turbulence, as might occur in front of perforations in the borehole. Emulsions can be encouraged to break (or destabilise) using chemicals, heat or just gentle agitation. Chemical destabilisation is the most common method and laboratory tests would normally be conducted to determine the most suitable combination of chemicals. [Pg.248]

The example just shown assumed one discount rate and one oil price. Since the oil price is notoriously unpredictable, and the discount rate is subjective, it is useful to calculate the NPV at a range of oil prices and discount rates. One presentation of this data would be in the form of a matrix. The appropriate discount rates would be 0% (undiscounted),.say 10% (the cost of capital), and say 20% (the cost of capital plus an allowance for risk). The range of oil prices is again a subjective judgement. [Pg.321]

It takes time to train a film interpreter. In addition, human interpretation of weld quality based on film radiography is very subjective, inconsistent, labour intensive, and sometimes biased. It is thus desirable to develop some forms of computer-aided systems. [Pg.181]

The reference sample in form of a cylinder or bar with probe placed on top of it, is subject to tensile or compressive loading using strength machine ( Instron type). [Pg.382]

A section related to materials sets out, apart from general requirements, that compliance with the material specifications of the directive can be achieved in one of the following forms by using materials which comply to harmonised standards, by using materials covered by a European approval of materials, a subject which will be explained further on, and by a particular material appraisal carried out by the notified body. [Pg.942]

We attempt to delineate between surface physical chemistry and surface chemical physics and solid-state physics of surfaces. We exclude these last two subjects, which are largely wave mechanical in nature and can be highly mathematical they properly form a discipline of their own. [Pg.2]

Surface Micelles. The possibility of forming clusters of molecules or micelles in monolayer films was first proposed by Langmuir [59]. The matter of surface micelles and the issue of equilibration has been the subject of considerable discussion [191,201,205-209]. Nevertheless, many ir-a isotherms exhibit nonhorizontal lines unexplained by equations of state or phase models. To address this, Israelachvili [210] developed a model for ir-u curves where the amphiphiles form surface micelles of N chains. The isotherm... [Pg.134]

Micellar structure has been a subject of much discussion [104]. Early proposals for spherical [159] and lamellar [160] micelles may both have merit. A schematic of a spherical micelle and a unilamellar vesicle is shown in Fig. Xni-11. In addition to the most common spherical micelles, scattering and microscopy experiments have shown the existence of rodlike [161, 162], disklike [163], threadlike [132] and even quadmple-helix [164] structures. Lattice models (see Fig. XIII-12) by Leermakers and Scheutjens have confirmed and characterized the properties of spherical and membrane like micelles [165]. Similar analyses exist for micelles formed by diblock copolymers in a selective solvent [166]. Other shapes proposed include ellipsoidal [167] and a sphere-to-cylinder transition [168]. Fluorescence depolarization and NMR studies both point to a rather fluid micellar core consistent with the disorder implied by Fig. Xm-12. [Pg.481]

The Langmuir-Hinshelwood picture is essentially that of Fig. XVIII-14. If the process is unimolecular, the species meanders around on the surface until it receives the activation energy to go over to product(s), which then desorb. If the process is bimolecular, two species diffuse around until a reactive encounter occurs. The reaction will be diffusion controlled if it occurs on every encounter (see Ref. 211) the theory of surface diffusional encounters has been treated (see Ref. 212) the subject may also be approached by means of Monte Carlo/molecular dynamics techniques [213]. In the case of activated bimolecular reactions, however, there will in general be many encounters before the reactive one, and the rate law for the surface reaction is generally written by analogy to the mass action law for solutions. That is, for a bimolecular process, the rate is taken to be proportional to the product of the two surface concentrations. It is interesting, however, that essentially the same rate law is obtained if the adsorption is strictly localized and species react only if they happen to adsorb on adjacent sites (note Ref. 214). (The apparent rate law, that is, the rate law in terms of gas pressures, depends on the form of the adsorption isotherm, as discussed in the next section.)... [Pg.722]

The mechanism of the Fischer-Tropsch reactions has been the object of much study (note Eqs. XVI11-55-XV111-57) and the subject of much controversy. Fischer and Tropsch proposed one whose essential feature was that of a metal carbide—patents have been issued on this basis. It is currently believed that a particular form of active adsorbed carbon atoms is involved, which is then methanated through a series of steps such as... [Pg.731]

Several years ago Baer proposed the use of a mahix A, that hansforms the adiabatic electronic set to a diabatic one [72], (For a special twofold set this was discussed in [286,287].) Computations performed with the diabatic set are much simpler than those with the adiabatic set. Subject to certain conditions, A is the solution of a set of first order partial diffei ential equations. A is unitary and has the form of a path-ordered phase factor, in which the phase can be formally written as... [Pg.137]


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