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Factors affecting amount

Factors Affecting Amount and Rate of Surface Runoff from ET Landfill Covers... [Pg.1068]

Carbon is alkylated ia the form of enolates or as carbanions. The enolates are ambident ia activity and can react at an oxygen or a carbon. For example, refluxing equimolar amounts of dimethyl sulfate and ethyl acetoacetate with potassium carbonate gives a 36% yield of the 0-methylation product, ie, ethyl 3-methoxy-2-butenoate, and 30% of the C-methylation product, ie, ethyl 2-methyl-3-oxobutanoate (26). Generally, only one alkyl group of the sulfate reacts with beta-diketones, beta-ketoesters, or malonates (27). Factors affecting the 0 C alkylation ratio have been extensively studied (28). Reaction ia the presence of soHd Al O results mosdy ia C-alkylation of ethyl acetoacetate (29). [Pg.199]

One consequence of this is that in a thermoplastic injection moulding the molecular orientations will vary from place to place according to the flow pattern. This may well set up sufficient stresses in the moulding to cause it to distort from its intended shape. Factors affecting the amount of orientation were discussed briefly in the previous chapter and by the author elsewhere. Sometimes the conditions required to minimise distortion may be such that the moulding cycle becomes too long to be economic. In these cases it may be necessary to modify the moulding or at least the position and number of feed... [Pg.202]

Although an appreciable amount of information is currently available about the factors affecting the design, performance, and installation of deflagration and detonation flame arresters, there is still a lack of information on many other relevant factors. A number of suggested test procedures and... [Pg.182]

Numerous factors affect the spread of luizardous substances into tlie area surrounding a leaking/buming container or contaituuent vessel. Evacuation decision-makers must carefully consider each of tliese factors in order to determine the conditions created by the release, tlie areas tluit have been or will be affected, and the heiilth affects on people. The factors tliat affect evacuation include amount of released material(s), physical and cheniical properties of the released material(s), health hazards, dispersion pattern, rate of release, and potential duration of release. Each of these factors is explained below. [Pg.497]

One of the important factors affecting composite properties is the amount of fiber it contains, i,e., percentage by volume. [Pg.819]

Sulphuric acid is used to a very large extent for pickling low-alloy steels. The rate at which it removes the scale depends on (q) the porosity and number of cracks in the scale, (b) the relative amounts of wiistite, decomposed wiistite, magnetite and haematite in the scale, and (c) factors affecting the activity of the pickle. [Pg.292]

Reacetylation of chitosan under proper conditions leads to products having the same solubility. Experiments showed that the amount of acetic anhydride was the most important factor affecting the N-acetylation degree of the chitosan. The effect of the means of adding materials and the amount of solvent on the reaction could not be ignored [70]. [Pg.156]

This strnctnring of liqnids into discrete layers when confined by a solid surface has been more readily observable in liquid systems other than water [1,55]. In fact, such solvation forces in water, also known as hydration forces, have been notoriously difficult to measure due to the small size of the water molecule and the ease with which trace amounts of contamination can affect the ordering. However, hydration forces are thought to be influential in many adhesive processes. In colloidal and biological systems, the idea that the hydration layer mnst be overcome before two molecules, colloidal particles, or membranes can adhere to each other is prevalent. This implies that factors affecting the water structure, such as the presence of salts, can also control adhesive processes. [Pg.37]

The rate of product to be applied is the critical factor affecting all residue studies. The rate should be the highest recommended rate for that particular crop and should be applied at the limit of the GAP for the specific crop. The test item should ideally be pre-weighed in a laboratory prior to making the application. In most cases, this procedure results in easier accountability of test items, more accurate measurement of required doses, and more accurate application in the field since only the correct amount of water is required to be added by the field operator. This procedure also reduces the quantity of test item required and hence reduces the waste, which has to be disposed of. An additional spare sample, which is weighed at the same time in case of mishap with the original sample may be prepared. [Pg.182]

Not surprisingly, The amount of di-t-butylperoxide (DtBP) is an important factor affecting the outcome of the reaction. The level of incorporation increases in proportion to the amount of DtBP (compare samples 1, 2, 6). Too much of the radical promoter is deleterious, since sample 6 was partially orosslinked, and an attempted modification reaction using 6.53 mmol of DtBP produced a completely insoluble product, which apparently was highly crosslinked. [Pg.305]

The third factor affecting dispersion is turbulence. Mechanical turbulence is caused by the roughness of the Earth s surface. Away from the surface, convective turbulence (heated air rising and cooler air falling) becomes increasingly important. The amount of turbulence and the height to which it operates depends on the surface roughness, wind speed and atmospheric stability. [Pg.575]

C02 is not the only factor involved in photosynthesis, so that for its use, other factors must be at levels that do not limit the process. Light, temperature, amount of available nutrients and the relative humidity are other environmental factors affecting photosynthetic activity. [Pg.104]

The paper first considers the factors affecting intramolecular reaction, the importance of intramolecular reaction in non-linear random polymerisations, and the effects of intramolecular reaction on the gel point. The correlation of gel points through approximate theories of gelation is discussed, and reference is made to the determination of effective functionalities from gel-point data. Results are then presented showing that a close correlation exists between the amount of pre-gel intramolecular reaction that has occurred and the shear modulus of the network formed at complete reaction. Similarly, the Tg of a network is shown to be related to amount of pre-gel intramolecular reaction. In addition, materials formed from bulk reaction systems are compared to illustrate the inherent influences of molar masses, functionalities and chain structures of reactants on network properties. Finally, the non-Gaussian behaviour of networks in compression is discussed. [Pg.377]

Another important factor affecting carbon deposition is the catalyst surface basicity. In particular, it was demonstrated that carbon formation can be diminished or even suppressed when the metal is supported on a metal oxide carrier with a strong Lewis basicity [47]. This effect can be attributed to the fact that high Lewis basicity of the support enhances the C02 chemisorption on the catalyst surface resulting in the removal of carbon (by surface gasification reactions). According to Rostrup-Nielsen and Hansen [12], the amount of carbon deposited on the metal catalysts decreases in the following order ... [Pg.60]

We have seen in the preceding chapters that a considerable amount of both experimental and theoretical evidence points to the existence of a transition layer at the boundary of two phases—in other words, of a layer in which the concentration of the phases is different from that in the bulk. It will, therefore, be advisable to consider quite generally what factors affect the concentration — for instance, the distribution of a solute in a solvent. [Pg.36]


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See also in sourсe #XX -- [ Pg.146 ]




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