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Intensive measurement technique

1 Quantities to be Measured and Objectives of Intensive Measurement Technique [Pg.132]

In intensive measurement, the following quantities are measured at short intervals on the pipeline  [Pg.132]

The following information can be obtained from these parameters  [Pg.132]

These three groups of parameters are arranged in order of their priority, so that the necessity for detailed investigation of succeeding parameters depends on the results from the preceding group. [Pg.132]

In group (a) pipe/soil potentials are evaluated. Here the explanations in the first half of Section 3.3.1 and criterion No. 1 in Table 3-1 are relevant. If the protection criterion is not fulfilled (1/ U, the cause must be found and remedied (e.g., removing foreign contacts, repairing major holidays or increasing the protection current). [Pg.132]


The cathodic protection of pipelines is best monitored by an intensive measurement technique according to Section 3.7, by an off potential survey eveiy 3 years and by remote monitoring of pipe/soil potentials. After installation of parallel pipelines, it can be ascertained by intensive measurements whether new damage of the pipe coating has occurred. These measurements provide evidence of possible external actions that can cause mechanical damage. [Pg.288]

One of the most interesting and important species in air is hydrogen peroxide (H2O2). Kok et al. (1978) suggested that H2O2 is an index of the HO2 radical concentration and better represents oxidation capacity than ozone. However, the relatively complicated and labor-intensive measurement technique hmits H2O2 measurements to very few sites and even then only occasionally (probably because of fixing to ozone as the oxidant leader species). [Pg.282]

The phase Doppler method utilizes the wavelength of light as the basis of measurement. Hence, performance is not vulnerable to fluctuations in light intensity. The technique has been successfully appHed to dense sprays, highly turbulent flows, and combustion systems. It is capable of making simultaneous measurements of droplet size, velocity, number density, and volume flux. [Pg.334]

XRD offers unparalleled accuracy in the measurement of atomic spacings and is the technique of choice for determining strain states in thin films. XRD is noncontact and nondestructive, which makes it ideal for in situ studies. The intensities measured with XRD can provide quantitative, accurate information on the atomic arrangements at interfaces (e.g., in multilayers). Materials composed of any element can be successfully studied with XRD, but XRD is most sensitive to high-Z elements, since the diffracted intensity from these is much lar r than from low-Z elements. As a consequence, the sensitivity of XRD depends on the material of interest. With lab-based equipment, surface sensitivities down to a thickness of -50 A are achievable, but synchrotron radiation (because of its higher intensity)... [Pg.198]

Contributions in this section are important because they provide structural information (geometries, dipole moments, and rotational constants) of individual tautomers in the gas phase. The molecular structure and tautomer equilibrium of 1,2,3-triazole (20) has been determined by MW spectroscopy [88ACSA(A)500].This case is paradigmatic since it illustrates one of the limitations of this technique the sensitivity depends on the dipole moment and compounds without a permanent dipole are invisible for MW. In the case of 1,2,3-triazole, the dipole moments are 4.38 and 0.218 D for 20b and 20a, respectively. Hence the signals for 20a are very weak. Nevertheless, the relative abundance of the tautomers, estimated from intensity measurements, is 20b/20a 1 1000 at room temperature. The structural refinement of 20a was carried out based upon the electron diffraction data (Section V,D,4). [Pg.46]

Ion exchange technique at Rocky Flats 378 Ion intensity measurements, vapor... [Pg.463]

Chemical methods for structure determination in diene pol3 mers have in large measure been superseded by infrared absorption techniques. By comparing the infrared absorption spectra of polybutadiene and of the olefins chosen as models whose ethylenic structures correspond to the respective structural units, it has been possible to show that the bands occurring at 910.5, 966.5, and 724 cm. are characteristic of the 1,2, the mns-1,4, and the m-1,4 units, respectively. Moreover, the proportion of each unit may be determined within 1 or 2 percent from measurements of the absorption intensity in each band. The extinction coefficients characteristic of each structure must, of course, be known these may be assigned from intensity measurements on model compounds. Since the proportions of the various units depend on the rates of competitive reactions, their percentages may be expected to vary with the polymerization temperature. The 1,2 unit occurs to the extent of 18 to 22 percent of the total, almost independent of the temperature, in free-radical-polymerized (emulsion or mass) poly butadiene. The ratio of trans-1,4 to cfs-1,4, however,... [Pg.239]

The centric scan, one-dimensional, DHK SPRITE measurement was used to study the ingress of lithium. This measurement technique was selected due to the low absolute sensitivity of 7Li (27% of [36]), the small amounts that are present and the short signal lifetimes (bulk Tx of 10 ms and T2 of 120 ps). In addition to the robust, quantitative nature of this technique, lithium is a quadrupolar nucleus and interpretation of the image intensity is more complex than spin % nuclei. Once again Eq. (3.4.2) is quantitatively correct for even quadrupolar nuclei due to the fact the longitudinal steady state does not influence the image intensity. [Pg.301]

Compared to the structures of Li+-water solvates, the structures of Li+-acetonitrile solvates are in general less studied. The Li+ ion was found to be four coordinate with the use of different techniques, e.g., by NMR where acetonitrile was gradually replaced by water in a 1.6 M solution of LiC104 (130), or based on IR intensities measured for the acetonitrile C-N stretching vibration (131,132). Even mixed coordination of a counter ion and acetonitrile were reported to be four coordinate, viz., in [Li(CH3CN)3Br] for 0.58 M LiBr in CH3CN (133). Extensive... [Pg.529]


See other pages where Intensive measurement technique is mentioned: [Pg.131]    [Pg.131]    [Pg.580]    [Pg.131]    [Pg.131]    [Pg.573]    [Pg.131]    [Pg.131]    [Pg.580]    [Pg.131]    [Pg.131]    [Pg.573]    [Pg.411]    [Pg.404]    [Pg.203]    [Pg.1295]    [Pg.47]    [Pg.292]    [Pg.350]    [Pg.2]    [Pg.344]    [Pg.130]    [Pg.617]    [Pg.9]    [Pg.286]    [Pg.7]    [Pg.463]    [Pg.158]    [Pg.48]    [Pg.575]    [Pg.178]    [Pg.25]    [Pg.409]    [Pg.423]    [Pg.426]    [Pg.441]    [Pg.329]    [Pg.423]   


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