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Pitch Control. Resinous constituents of wood cause problems in paper machines by sticking to the rollers and causing spots or holes in the paper the worst cases cause paper webs to mpture. Costly stoppages, wastages, and quaUty problems because of these resinous substances can be avoided by using Upases (84). [Pg.299]

A small steady supply of water entering a column through solubility or entrainment can, in some cases, cause severe cycling at constant intervals during which time the water is expelled. After expulsion of water, the column lines out until enough is built up for another cycle. [Pg.303]

Sulfonyl bromides and iodides react similarly217-218-225 copper-salt catalysis in these cases facilitates the additions but is not absolutely necessary however, it influences the stereochemistry of the additions. Addition of sulfonyl iodides226 as well as the uncatalyzed thermal addition of sulfonyl bromides227 to alkynes leads to an exclusive trans-addition, whereas CuBr2 catalysis in the latter case causes the formation of cis-addition products to some extent (11 16%) correspondingly, copper-salt catalysis in sulfonyl chloride additions to alkynes leads to the formation of a mixture of Z,E-isomers228-229 (equation 40). [Pg.189]

During the forties and fifties, episodes of severe air pollution occurred In a number of urban and Industrial areas. They were responsible for 111 health and In some cases caused death among the populations concerned. As the scientific and public Information base on the adverse effects of urban air pollution Increased, so did public demand for control measures. As a result, many Industrial countries Introduced comprehensive air pollution control laws at various times from the mid-fifties onwards. Industrial response to these laws led to the application of control techniques which effectively reduced the emissions of some pollutants. However there are other sources and factors which can obscure the benefits of these control actions. For example, consider urban growth. In 1980 there were 35 cities with populations over 4 million. By the year 2000 this number will nearly double to 66, and by the 2025, this number will more than double to an estimated 135 (9). In developing countries, from 1980 to the year 2000, It Is estimated that twice as many people will live In cities of a total population of 1 million or more In Latin America (101 million to 232 million) and East Asia (132 million to 262 million). Three times as many people will live In cities of 1 million or more In South Asia (106 million to 328 million) and four times as many In Africa (36 million to 155 million) (10). Accompanying this rapid growth are Increases In Industrial activity... [Pg.165]

Direct fluorinations with elemental fluorine still are not feasible on an industrial scale today they are even problematic when carried out on a laboratory-scale [49-53]. This is caused by the difficulty of sustaining the electrophilic substitution path as the latter demands process conditions, in particular isothermal operation, which can hardly be realized using conventional equipment. As a consequence, uncontrolled additions and polymerizations usually dominate over substitution, in many cases causing large heat release which may even lead to explosions. [Pg.597]

An orientation-dependent asymmetry in line intensity of a quadrupole doublet is, in contrast to the aforementioned case, caused by the polarization response of... [Pg.495]

Rare forms of DM have been reported and account for 1% to 5% of all diagnosed cases. Causes of these rare forms of DM include specific genetic conditions, surgery, drugs, malnutrition,... [Pg.644]

However, both assumptions are in general not valid1, thus complicating the comparison of results in the various papers and, in some cases, causing errors in the extrapolation of one result from another within a paper, as we shall see. [Pg.139]

Recommended therapy in the uncomplicated case caused by fully susceptible strains is 4 weeks of either high-dose penicillin G or ceftriaxone, or 2 weeks of combined therapy with high-dose penicillin G plus gentamicin (Table 37-3). [Pg.414]

Similarly to 17 Th neutral loss, 18Th mass shifts are also very common, corresponding to the loss of water. Such shifts are (in most cases) caused by elimination of hydroxyl group from serine and threonine side chains. [Pg.205]

One of the major causes of the distorted behaviour seen when rough electrodes are used is due to the fact that different parts of the interface have different bulk resistance pathways to them, in some cases causing transmission line type behaviour. [Pg.288]

Strains of type G were isolated from Argentinian soil in 1968. It is suggested that type G do not produce sufficiently high levels of toxin, so far no lethal cases caused by type G have been reported (Ciccarelli et ah, 1977). [Pg.203]

As intake increases above the range of adequacy a region will be reached at which the adverse effects of excessive intake will begin to manifest themselves. Figure 9.1 depicts these interesting dose-response curves, and the curve at the right side of the figure represents a typical dose-response relationship for toxicity, in this case caused by excessive intakes of substances we cannot live without at lower doses. [Pg.262]

A poster cannot communicate as much information as a journal article can. When designing a poster, the presenter should accept this constraint and limit the poster to the essential information. If too much information is included, the poster will overwhelm the audience and in many cases cause passershy to give up on that poster and move on to the next one. —Alley (2003)... [Pg.298]

Roots pumps must be exactly level. When attaching the pump it is necessary to ensure that the pump is not under any tension or strain whatsoever. Any strains in the pump casing caused by the connection lines shall be avoided. Any strain to which the pump is subjected vi/ill endanger the pump since the clearances inside the roots pump are very small. [Pg.142]

Several trophic levels must be considered. Breeding plants with greater allomone content in some cases causes specialist herbivores to accumulate higher levels of these compounds and discourages parasites that normally control herbivore levels (36). The presence of secondary compounds may also alter the usefulness of the crop plant to man or his domestic animals. Lines of cotton with high gossypol content have increased insect resistance with regard to a nunter of insects, but have reduced value as food materials for livestock. [Pg.307]


See other pages where Cases causes is mentioned: [Pg.124]    [Pg.123]    [Pg.274]    [Pg.425]    [Pg.219]    [Pg.353]    [Pg.523]    [Pg.325]    [Pg.422]    [Pg.1068]    [Pg.1081]    [Pg.91]    [Pg.386]    [Pg.189]    [Pg.206]    [Pg.209]    [Pg.315]    [Pg.75]    [Pg.521]    [Pg.784]    [Pg.29]    [Pg.233]    [Pg.312]    [Pg.203]    [Pg.161]    [Pg.249]    [Pg.342]    [Pg.108]    [Pg.774]    [Pg.322]    [Pg.323]    [Pg.274]    [Pg.465]    [Pg.306]   
See also in sourсe #XX -- [ Pg.2 , Pg.13 , Pg.17 , Pg.27 , Pg.28 , Pg.34 ]




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