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Limiting mean

When measuring the noise level, i.e. the limiting mean sound power level in dB for airborne noise emitted by a machine, reference may be made to the following lEC and ISO publications ... [Pg.259]

These ai e, of course, the limits for the air-free mixture. But remember, the original mixture, before we removed the air, had 2% O2. So the lower limit for the original mixture (with the air added back) is 25.4% + 2/0.209 = 35.0 (the increased lower limit means greater percentage of the combustible mixture in air or lower percentage of air required with the combustible mixture to cause combustion). It is logical that less air is needed since the original mixture (with the air added back) has a head start on combustion (with the contained 2% O2). [Pg.281]

Surface sensitivity in LEED is provided by the limited mean free path for inelastic scattering of slow electrons. This mean fi-ee path is the distance traveled by an electron in the solid before it collides inelastically, loses energy, and thus becomes... [Pg.257]

It is conceptually impossible to be complete in a mathematical sense in the constmctioii oi event trees and fault trees. What matters is the approach to completeness and the abihiy lo demonstrate with reasonable assurance that only small contributions are omitted. This inherent limitation means that any calculation using this methodology is always subject to revision and to doubt as to its completeness. [Pg.5]

Binding occupational exposure limit values reflect feasibility factors related to social acceptability. When the results of environmental monitoring have to be compared with OELs, factors that influence exposure and that entail preventive policies are considered. For these values member states shall establish a corresponding national binding occupational exposure limit value based on but not exceeding the community limit value. That is, a binding limit means a minimum requirement. [Pg.368]

In other companies, senior managements knowledge of operations and process safety may be limited, meaning that your first t2isk is to provide basic information. In either case, its obviously important to assess—in advance— the information needs of the people whose endorsement you seek. Otherwise,... [Pg.11]

This brief analysis explains why it is very important to know whether the Hubbard relation is reproduced in the liquid cage model. The existence of the Hubbard limit means that orientational relaxation is insensitive to the precise details of the interaction. Below, it is shown that this is the case. [Pg.252]

At sufficiently low strain, most polymer materials exhibit a linear viscoelastic response and, once the appropriate strain amplitude has been determined through a preliminary strain sweep test, valid frequency sweep tests can be performed. Filled mbber compounds however hardly exhibit a linear viscoelastic response when submitted to harmonic strains and the current practice consists in testing such materials at the lowest permitted strain for satisfactory reproducibility an approach that obviously provides apparent material properties, at best. From a fundamental point of view, for instance in terms of material sciences, such measurements have a limited meaning because theoretical relationships that relate material structure to properties have so far been established only in the linear viscoelastic domain. Nevertheless, experience proves that apparent test results can be well reproducible and related to a number of other viscoelastic effects, including certain processing phenomena. [Pg.820]

For several technical reasons, it is not possible to acquire NMR data with perfect phase. One reason is the inability to detect XY magnetisation correctly another is the fact that we are unable to collect the data as soon as the spins are excited. These limitations mean that we have to phase correct our spectrum so that we end up with a pure absorption spectrum. What we don t want is a dispersion signal (see Spectrum 4.2). [Pg.36]

It should be noted that the basic reactions used to prepare phthalocyanine derivatives today are fundamentally those developed by Linstead and coworkers in the 1930s [52-54]. Due to the large number of substituted phthalocyanines described in the literature, space limitations mean that a detailed review of synthetic aspects cannot be provided here. The following discussion is concerned with the synthesis of lanthanide phthalocyanines via (i) template tetramerization of phthalonitrile with lanthanide salts, (ii) direct metalation of the metal-free ligands by the salts or (iii) metal exchange of a labile metal ion or ions for a lanthanide. [Pg.231]

Xenobiotic Mean Limits Mean Limits Mean Limits... [Pg.110]

Explosive nature of chemical substances is described with upper and lower explosion limits. The explosiveness of vapour cloud depends especially on the lower explosion limit (LEL). The LEL is the concentration of vapour, at which the vapour cloud is possible to ignite. The wider range between explosion limits means, that it is more probable that the formed vapour cloud is in the flammable region, i.e. the higher tendency for explosion. Edwards and Lawrence (1993) have used explosive limits to determine the explosiveness of chemical substances. [Pg.49]

Instrumentation and methods currently available provide limited means for realtime measurements of the continuous wave (CW) and transient characteristics of luminescent substances. The measurement, in real time, of the spatial distribution of a parameter of interests, for instance, in cells and in tissue cannot be attained with present technology. Optical fibers are used to monitor the response of a sensor in limited regions in space. [Pg.255]

The reproductive/developmental toxicity screening test can provide initial information on possible effects on reproduction and/or development and may make it possible to identify a substance as being toxic to reproduction, i.e., the test gives a clear positive result. However, this test offers only limited means of detecting postnatal manifestations of prenatal exposure or effects that may be induced during postnatal exposure. In addition, because of the study design (e.g., relatively small numbers of animals per dose level, relatively short smdy duration), the test will not provide evidence for definite claims of no effects. [Pg.187]

The probability that 99.7 % of the correct measurement results are expected to lie within the action limits means that only 3 out of 1000 correct measurement results will lie outside this range. Correct means that they belong to the same statistical distribution of data. Therefore the probability is very high that a result that is outside the action range is incorrect. [Pg.275]

As long as care is taken so that effective binary diffusivity obtained from experiments under the same set of conditions is applied to a given problem, the approach works well. Although the limitations mean additional work, because of its simplicity and because of the unavailability of the diffusion matrices, the effective binary diffusion approach is the most often used in geological systems. Nonetheless, it is hoped that effort will be made in the future so that multi-component diffusion can be handled more accurately. [Pg.254]

Variously substituted nitrile imines are easily available and react readily with a wide range of double and triple bonds. Intermolecular cycloaddition is therefore an area of major interest, and a large proportion of the papers on the use of nitrile ylides in synthesis is concerned with the exploitation of this reaction. Space limitation means, regrettably, that work leading to results that were predictable on the basis of known chemistry (19) has generally not been included. [Pg.502]

But as long as simple bodies were defined as anything not yet known to be compound, chemists felt it necessary to call their readers attention to the limited meaning of such a conditional identity. Fourcroy s statement in 1800 is typical ... [Pg.215]

Tricoordinated boron compounds (boranes) are coordinatively unsaturated and their chemistry is dominated by reactions in which complexes are formed. These complexes are either neutral molecules (borane complexes), anions (borates) or boron cations. Space limitations mean that little or no attention will be paid to complexes containing several boron atoms and to species of the type L-BH3, [BH,]- and [L2BH2]+ (L = neutral ligand), discussed in detail in several books and reviews. Similarly, little attention will be paid to the plethora of metal borates and the cyclic and polymeric amino- and phosphino-boranes. [Pg.81]

Here the 0 of the limit means sufficiently small for the limit to exist which is to be understood more precisely in the context of the experiment. A corresponding z-meter in the multivariable case would have n xrdials, each of which is tweaked in turn (holding the remaining n — 1 dials fixed) to determine the successive partial derivatives Zi,i = 1,2,..., n. It is noteworthy that the multivariate dz carries sufficient information to evaluate each of its possible monovariate dxi derivatives zj, confirming its status as a more powerful type of mathematical object. [Pg.8]

Mean. Limits Mean. Limits. Mean. Limits. [Pg.346]

In this section we will discuss in some detail the relationship between molecular mechanics force field parameters and real physical parameters. As mentioned before, the fundamental difference between spectroscopic and molecular mechanics force fields is that the former are molecule-specific while the latter are general. Empirical force field parameters can be used for the calculation of unknown structures and their strain energies, and for the prediction of vibrational frequencies of new compounds. However, the parameters themselves generally have limited meaning. [Pg.32]


See other pages where Limiting mean is mentioned: [Pg.149]    [Pg.1121]    [Pg.489]    [Pg.7]    [Pg.449]    [Pg.163]    [Pg.248]    [Pg.273]    [Pg.60]    [Pg.500]    [Pg.218]    [Pg.357]    [Pg.167]    [Pg.266]    [Pg.264]    [Pg.771]    [Pg.106]    [Pg.318]    [Pg.322]    [Pg.152]    [Pg.133]    [Pg.334]    [Pg.141]    [Pg.30]    [Pg.7]   
See also in sourсe #XX -- [ Pg.290 ]




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