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Classical determinism

Once the best method of dealing with interferences has been decided upon and the most appropriate method of determination chosen, the analysis should be carried out in duplicate and preferably in triplicate. For simple classical determinations the experimental results must be recorded in the analyst s notebook. However, many modern instruments employed in instrumental methods of analysis are interfaced with computers and the analytical results may be displayed on a visual display unit, whilst a printer will provide a printout of the pertinent data which can be used as a permanent record. [Pg.13]

The detection of thorium in stars of very low metallicity by Patrick Frangois and Monique and Frangois Spite has opened the way to a direct determination of the age of the most ancient stars, and hence also of the age of the Galaxy. The age of some of the oldest halo stars has been estimated at 15.6 billion years, with an error margin of 2 billion years. This agrees with the classic determination of the age of the oldest globular clusters at 14.9 1.5 billion years, and the age of the Universe by means of remote type la supernovas at 14.2 1.7 billion years (Arnould Takahashi 1999). [Pg.183]

In retrospect, one can see that Boltzmann s inspired conjecture (13.69) served, through (13.77), to anticipate an essential feature of the probabilistic quantum description that was to supplant classical determinism in the 20th century. Boltzmann and his followers specifically captured the key probabilistic feature (13.69) that could bring proper metric geometrical character (13.77) to macroscopic-level thermodynamic description, despite gross errors of then-current microscopic dynamical theory. [Pg.449]

Einstein became a member of the Scientific Committee and took an active part in the discussions on quantum mechanics, which was the theme of the 1927 Conference. Indeed, the famous Einstein-Bohr discussions on classical determinism versus the quantum statistical causality took place in Brussels at the Solvay Conferences of 1927 and 1930, and continued thereafter. [Pg.7]

Quantum mechanics has tremendous philosophical consequences which are still debated to this day, and which go well beyond the scope of this book. Perhaps the most important of these consequences is the destruction of classical determinism, and the recognition that it is impossible to make observations without fundamentally changing the system being observed. This result is quantified by the Heisenberg Uncertainty Principle, which is simply a consequence of the wavelike nature of matter. [Pg.107]

Figure 5.11 shows one of the most counterintuitive results of quantum mechanics. There are fundamental limits to our ability to make certain measurements—the act of determining the state of a system intrinsically perturbs it. For example, it is impossible to measure position and momentum simultaneously to arbitrarily high accuracy any attempt to measure position automatically introduces uncertainty into the momentum. Similarly, a molecule which is excited for a finite period of time cannot have a perfectly well-defined energy. As a result, classical determinism fails. It is not possible, even in principle, to completely specify the state of the universe at any instant, hence the future need not be completely defined by the past. These results are usually phrased something like ... [Pg.110]

We conclude this chapter by going back to Albert Einstein, whose work was instrumental in the evolution of the quantum theory. Einstein was unable to tolerate the limitations on classical determinism that seem to be an inevitable consequence of the developments outlined in this chapter, and he worked for many years to construct paradoxes which would overthrow it. For example, quantum mechanics predicts that measurement of the state of a system at one position changes the state everywhere else immediately. Thus the change propagates faster than the speed of light—in violation of at least the spirit of relativity. Only in the last few years has it been possible to do the appropriate experiments to test this ERPparadox (named for Einstein, Rosen and Podolsky, the authors of the paper which proposed it). The predictions of quantum mechanics turn out to be correct. [Pg.124]

Corrosivity of used oils. The classical determination of TBN and TAN involves a titrimetric procedure, whereby the oil sample is dissolved in a particular solvent system and neutralized by strong acid or strong base (ASTM D664 or 2896), equivalent to (IP 171 or 276). TBN and TAN values do not correlate with corrosivity and the titrimetric analysis has a very limited ability to differentiate between acids of varying strengths. A quantitative differential infrared spectroscopy technique used to monitor the neutralization reaction is more meaningful, since the technique applies to reactions in hydrocarbon solvents. The classical reaction between corrosive acids and hard-core RMs results in formation of the metal salt of the acid and carbonic acid ... [Pg.90]

Denotes the spin-alternant quasi-classical determinant. [Pg.310]

While less accurate than the classic determination of the ground state hyperfine splitting, the combination of Is and 2s hfs intervals... [Pg.335]

However, there are obvious differences between the classically determined octanol-water partition data and the reversed phase chromatographic partition data due to the different nature of the partitioning solvents. The correlation between shake flask octanol water partition coefficients and chromatographic retention factor kw (0 % organic solvent) was described to be low (Valko 2004) when structurally diverse compound sets were analysed. Using the q>o or the CHI lipophilicity index an improvement in agreement to logPow was reported (Valko 1993,1997). [Pg.463]

With strong oxidizing agents such as chromium trioxide in aqueous sulfuric acid, alkylpyrroles are converted into maleimides, e.g., 154. This oxidative technique played an important part in the classical determination of porphyrin structures. Milder oxidizing agents, such as hydrogen peroxide, convert pyrroles into pyrrolinones, e.g., oxidation of the parent heterocycle gives a tautomeric mixture of pyrrolin-2-ones 155 and 156. [Pg.418]

Ash content and insoluble ash contents were low, though a low variation was observed (2.9 to 4.1%, 0.27 to 0.68%, for total and acid insoluble ashes, respectively (Table 1). The acid insoluble ashes are a classic determination of cleanliness in botanical products usually a maximum of 1% is accepted for food products. All Griffonia samples were well below that threshold. In both the Inspection Mannals, there are defined degrees of tolerances allowed (i.e. % by number or weight of defective fruit) (4). Ash content and insoluble ash contents are generally part of ISO specifications and should be considered to include in futnre standards of Griffonia seeds. [Pg.384]

TABLE 4.2 Molar Absorptivity Coefficients for Compounds Formed During the Classical Determinations of Some Metal Ions. X = Wavelength of Maximum Absorption. For Experimental Conditions, see Ref. [13]... [Pg.101]

The vapor-water phase transition occurs when classically determined action (A8) approaches to the minimal vallue h due to too short lifetime Tq of longitudinally vibrating dipoles. On the other hand, the transition of ice Ih to other ice modification occurs when the translational bandwith Av—t-band approaches to classically estimated limit (A36) (A38). [Pg.426]

From an economic viewpoint, the classical determination of alloy phase diagrams is a laborious process, involving alloy preparation and heat treatment, compositional, structural, and microstructural analysis (and, even then, not yielding reliable phase boundary information at low temperatures due to kinetic limitations). While this investment is justified for alloys of major technical importance, the need for better economics has driven an effort to use alternative methods of phase discovery such as multiple source, gradient vapor deposition or sputter deposition followed by automated analysis alternatively, multicomponent diffusion couples are used to map binary or ternary alloy systems structurally and by properties (see Section 6). These techniques have been known for decades, but they have been reintroduced more recently as high-efficiency methodologies to create compositional libraries by a combinatorial approach, inspired perhaps by the recent, general introduction of combinatorial methods in chemistry. [Pg.118]

The CMC theory shows a good prediction of the reaction pathway from the measurements in this much-studied biochemical system. Both the MDS diagram itself (fig.8.5A) and the predicted reaction pathway (fig. 8.5B) resemble the classically determined reaction pathway (fig. 8.1). In addition, CMC measurements yield information about the underlying kinetics of the network. For example, species connected by small numbers of fast reactions will have smaller distances between them than species connected by a slow reaction. We therefore conclude that the CMC method is useful and predict that it will be applicable to many other complex reaction systems, as is shown in [12] and section 13.5. [Pg.95]

In Chapter 2, several types of kinetic schemes were examined in detail. While the mathematical apparatus was developed to describe these cases, little was said about other methods used in kinetic studies or about experimental techniques. In this chapter, we will describe some of the methods employed in the study of kinetics that do not make use of the integrated rate laws. In some cases, the exact rate law may be unknown, and some of the experimental techniques do not make use of the classical determination of concentration as a function of time to get data to fit to a rate law. A few of the techniques described in this chapter are particularly useful in such cases. [Pg.79]

Chkhartishvih, L., D. Lezhava, and O. Tsagareishvili. 2000. Quasi-classical determination of electronic energies and vibration frequencies in boron compounds. J. Solid State Chem. 154 148-152. [Pg.72]

The analytical methods for the characterization of raw materials and reaction products are given in Table 3. They are mainly standardized methods and most of them are classical. Determinations of polymer content and hydroxyl values were performed to control side reactions such as dimerization and diol formation. [Pg.145]

The detail points on profiles were read by tracing the profiles drawn on a map of scale 1 1000. The model coordinates and heights were determined for detail points on the profiles. The model coordinates were first transformed into the Gauss-Kruger coordinate system as a geodetic network system and then to a system of classical determined profiles. [Pg.205]


See other pages where Classical determinism is mentioned: [Pg.57]    [Pg.85]    [Pg.103]    [Pg.318]    [Pg.57]    [Pg.14]    [Pg.117]    [Pg.63]    [Pg.107]    [Pg.107]    [Pg.109]    [Pg.111]    [Pg.35]    [Pg.57]    [Pg.172]    [Pg.119]    [Pg.890]    [Pg.20]    [Pg.123]    [Pg.305]    [Pg.362]    [Pg.2724]    [Pg.409]    [Pg.362]    [Pg.889]    [Pg.61]   


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