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Natural technique

In modern art, analytical techniques are of increased importance in flavor design. Sense of flavor is in general conservative and the use of artificial substances in this field is far less encouraged compared with fragrances. Consequently, reproduction of natural aroma is favored, and therefore analysis of foodstuff is the dominating force in innovation. However, naturally, techniques used in flavor analysis are applicable to fragrance analysis as well. [Pg.602]

The given examples and, although singularities under low Wagner number conditions were treated, also the good agreement with measurements show clearly that this solution technique is very well suited for the type of problems dealt with. When the conductivity is constant, which is often encountered, the boundary element method appears even to be the most natural technique because only data on the boundaries are needed and used. [Pg.221]

The Fourier series is a method for describing a complex periodic signal. It affords a representation of the signal as a function of both time and frequency in such a manner that one can easily extract a frequency spectrum for the signal. Since many bioelectric signals may be considered periodic (EKG and EEG wave forms, for example), Fourier-series representation is a natural technique to use, although as will be shown later, other methods may prove more useful when specific data-reduction techniques are to be used. [Pg.196]

The technique of neutralization and the production of superbase systems from synthetic sulfonates are similar to those employed for the natural sulfonates. [Pg.360]

It is possible that more than one of these drive mechanisms occur simultaneously the most common combination being gas cap drive and natural aquifer drive. Material balance techniques are applied to historic production data to estimate the contribution from each drive mechanism. [Pg.192]

This technique is suitable where the natural mobility ratio is greater than 1.0. Polymer chemicals such as polysaccharides are added to the injection water. -... [Pg.210]

Artificial lift techniques are discussed in Section 9.6. During production, the operating conditions of any artificial lift technique will be optimised with the objective of maximising production. For example, the optimum gas-liquid ratio will be applied for gas lifting, possibly using computer assisted operations (CAO) as discussed in Section 11.2. Artificial lift may not be installed from the beginning of a development, but at the point where the natural drive energy of the reservoir has reduced. The implementation of artificial lift will be justified, like any other incremental project, on the basis of a positive net present value (see Section 13.4). [Pg.339]

In the near future the technique will be further evaluated using ultrasonic signals from natural defects, e.g., fatigue cracks. The performance measure and the parameter optimization procedure wilt also be refined in order to obtain a computationally efficient implementation, easy to use for a trained operator. [Pg.95]

Therefore, it seems natural to turn to time-frequency techniques in order to perform an efficient defect detection through the signal provided by the sensors. [Pg.360]

An other worst case for the projection technique used is the ease if corrosion is on both sides of the wall in the double wall penetration. Then by the nature of the double wall penetration it is only possible to determine the integral material loss in the penetrating direction without any possibility to distinguish the side on which the erosion can be found. [Pg.567]

Considering existing microscopical techniques, one can find that non-destmctive information from the internal stmcture of an object in natural conditions can be obtained by transmission X-ray microscopy. Combination of X-ray transmission technique with tomographical reconstmction allows getting three-dimensional information about the internal microstmcture [1-3]. In this case any internal area can be reconstmcted as a set of flat cross sections which can be used to analyze the two- and three-dimensional morphological parameters [4]. For X-ray methods the contrast in the images is a mixed combination of density and compositional information. In some cases the compositional information can be separated from the density information [5]. Recently there has been a... [Pg.579]

Up to now the Reference Block Method and the DGS-Method are world wide the most important techniques for evaluating defect signals in manual Ultrasonic Testing. Even today, individual national standards refer to either one of these two echo evaluation techniques. However, both reflected echo signals from natural defects are compared with an echo from a known reference reflector at the same distance. The result of the evaluation is either... [Pg.812]

We have considered briefly the important macroscopic description of a solid adsorbent, namely, its speciflc surface area, its possible fractal nature, and if porous, its pore size distribution. In addition, it is important to know as much as possible about the microscopic structure of the surface, and contemporary surface spectroscopic and diffraction techniques, discussed in Chapter VIII, provide a good deal of such information (see also Refs. 55 and 56 for short general reviews, and the monograph by Somoijai [57]). Scanning tunneling microscopy (STM) and atomic force microscopy (AFT) are now widely used to obtain the structure of surfaces and of adsorbed layers on a molecular scale (see Chapter VIII, Section XVIII-2B, and Ref. 58). On a less informative and more statistical basis are site energy distributions (Section XVII-14) there is also the somewhat laige-scale type of structure due to surface imperfections and dislocations (Section VII-4D and Fig. XVIII-14). [Pg.581]

Studies to determine the nature of intermediate species have been made on a variety of transition metals, and especially on Pt, with emphasis on the Pt(lll) surface. Techniques such as TPD (temperature-programmed desorption), SIMS, NEXAFS (see Table VIII-1) and RAIRS (reflection absorption infrared spectroscopy) have been used, as well as all kinds of isotopic labeling (see Refs. 286 and 289). On Pt(III) the surface is covered with C2H3, ethylidyne, tightly bound to a three-fold hollow site, see Fig. XVIII-25, and Ref. 290. A current mechanism is that of the figure, in which ethylidyne acts as a kind of surface catalyst, allowing surface H atoms to add to a second, perhaps physically adsorbed layer of ethylene this is, in effect, a kind of Eley-Rideal mechanism. [Pg.733]

The importance of low pressures has already been stressed as a criterion for surface science studies. However, it is also a limitation because real-world phenomena do not occur in a controlled vacuum. Instead, they occur at atmospheric pressures or higher, often at elevated temperatures, and in conditions of humidity or even contamination. Hence, a major tlmist in surface science has been to modify existmg techniques and equipment to pemiit detailed surface analysis under conditions that are less than ideal. The scamiing tunnelling microscope (STM) is a recent addition to the surface science arsenal and has the capability of providing atomic-scale infomiation at ambient pressures and elevated temperatures. Incredible insight into the nature of surface reactions has been achieved by means of the STM and other in situ teclmiques. [Pg.921]

The relative simplicity of tlie method and the penetrative nature of the x-rays, yield a technique that is sensitive to elements with Z > 10 down to a few parts per million (ppm) and can be perfonued quantitatively from first principles. The databases for PIXE analysis programs [21, 22 and 23] are typically so well developed as to include accurate fiindamental parameters, allowing the absolute precision of the technique to be around 3% for major elements and 10-20% for trace elements. A major factor m applying the PIXE teclmique is that the bombardmg energy of the... [Pg.1841]


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See also in sourсe #XX -- [ Pg.256 , Pg.280 ]




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