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Focused concept

With the advent of short pulsed lasers, investigators were able to perfonn time resolved coherent Raman scattering. In contrast to using femtosecond pulses whose spectral widtii provides the two colours needed to produce Raman coherences, discussed above, here we consider pulses having two distinct centre frequencies whose difference drives the coherence. Since the 1970s, picosecond lasers have been employed for this purpose [113. 114], and since the late 1980s femtosecond pulses have also been used [115]. Flere we shall briefly focus on the two-colour femtosecond pulsed experiments since they and the picosecond experiments are very similar in concept. [Pg.1210]

The history of EM (for an overview see table Bl.17,1) can be interpreted as the development of two concepts the electron beam either illuminates a large area of tire sample ( flood-beam illumination , as in the typical transmission electron microscope (TEM) imaging using a spread-out beam) or just one point, i.e. focused to the smallest spot possible, which is then scaimed across the sample (scaiming transmission electron microscopy (STEM) or scaiming electron microscopy (SEM)). In both situations the electron beam is considered as a matter wave interacting with the sample and microscopy simply studies the interaction of the scattered electrons. [Pg.1624]

Whereas most chemists focused their attention on speculation about atoms and the question of atomic weights, the constant multiplicity in compounds occupied an increasingly central role. The new concept of substitution, i.e., the replacement of one element by another in a compound, started to make a major impact on chemistry in the 1840s. It was probably Dumas, who in the 1830s at the request of his father-in-law (who was the director of the famous Royal Sevres porcelain factory) resolved an event that upset a royal dinner party at the Tuil-... [Pg.29]

Our strategy in proceeding, therefore, is to write separate expressions for the forces cited in items (1) and (2), and then set them equal to each other as required by item (3). Since we have discussed osmotic effects in Chap. 8 and elastic forces in Chap. 3, we shall invoke certain concepts and relationships from these chapters in this discussion. In this derivation we continue to omit numerical coefficients and some of the less pertinent parameters (although we retain Vj for the sake of Problem 5 at the end of the chapter), and focus attention on the relationship between a, M, and the interaction parameter x-... [Pg.618]

Writing by Bubble Forming. Bubble formation occurs under thin metal layers on polymeric substrate films, caused by local evaporation when hit by a focused laser beam (see Fig. 3c). Bubble formation occurs as in the DIP concept in dye-in-polymer films which are covered by a thin metal (mostiy gold) or ceramic layer (6) (see Fig. 3d). [Pg.140]

Statistical Process Control Statistical process control (SPG), also called statistical quahty control (SQC), involves the apphcation of statistical concepts to determine whether a process is operating satisfactorily The ideas involved in statistical quahty control are over fifty years old, but only recently with the growing worldwide focus on increased productivity have applications of SPG become widespread. If a process is operating satisfactorily (or in control ), then the variation of product quahty tails within acceptable bounds, usually the minimum and maximum values of a specified composition or property (product specification). [Pg.735]

This guideline describes methods to help the chemical processing industry apply the CCPS chemical process safety concepts to outsourced manufacturing operations, specifically the tolling vendor-client relationship. In addition to the focus on process safety, information and examples provided in this text foster good practices relative to community and worker health, and environmental responsibility. [Pg.1]

A striking example of the importance of narrowing the focus in research, which is what the concept of the parepisteme really implies, is the episode (retailed in Chapter 3, Section 3.1.1) of Eilhard Mitscherlich s research, in 1818, on the crystal forms of potassium phosphate and potassium arsenate, which led him, quite unexpectedly, to the discovery of isomorphism in crystal species and that, in turn, provided heavyweight evidence in favour of the then disputed atomic hypothesis. As so often happens, the general insight comes from the highly specific observation. [Pg.159]


See other pages where Focused concept is mentioned: [Pg.104]    [Pg.129]    [Pg.13]    [Pg.217]    [Pg.386]    [Pg.147]    [Pg.240]    [Pg.104]    [Pg.129]    [Pg.13]    [Pg.217]    [Pg.386]    [Pg.147]    [Pg.240]    [Pg.808]    [Pg.759]    [Pg.883]    [Pg.1411]    [Pg.1629]    [Pg.1643]    [Pg.1803]    [Pg.2698]    [Pg.182]    [Pg.517]    [Pg.60]    [Pg.476]    [Pg.373]    [Pg.318]    [Pg.1522]    [Pg.72]    [Pg.266]    [Pg.268]    [Pg.282]    [Pg.296]    [Pg.297]    [Pg.352]    [Pg.38]    [Pg.179]    [Pg.178]    [Pg.21]    [Pg.46]    [Pg.76]    [Pg.96]    [Pg.105]    [Pg.131]    [Pg.168]    [Pg.224]    [Pg.510]    [Pg.581]    [Pg.693]   
See also in sourсe #XX -- [ Pg.15 ]




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Biogas biorefineries other biorefinery concepts with focus

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