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Coordinate concentration

First, let us find the eigenvectors for zero eigenvalue. Dimension of zero eigenspace is equal to the number of fixed points in the discrete dynamical system. If A,- is a fixed point then the correspondent eigenvalue is zero, and the right eigenvector r has only one nonzero coordinate, concentration of A, r = 5ij. [Pg.131]

From the general formulae describing the kinetics of electron tunneling reactions it follows that with the constant value of the parameter ae the kinetic curves represent the function of the dimensionless parameter. t. Therefore, kinetic curves obtained at different temperatures with the coordinates concentration vs. log observation time must be just shifted with respect to the time axis. Consequently, the lack of temperature dependence... [Pg.158]

Alprazolam (Xanax), lorazepam (Ativan), and oxazepam (Serax) are metabolized and cleared from the body more quickly than the other members of this family, and are therefore more likely to produce withdrawal symptoms when they are discontinued. These three drugs, however, are less likely to produce side effects such as impaired coordination, concentration, and memory and muscular weakness or sedation. [Pg.71]

In the latter case, the area supervisor may become a service chief with greater hands-on involvement, with the field coordinator concentrating on marshaling required resources and maintaining effective communications. The choice depends to a great extent on the size and complexity of the facility, and the resources available for the EMO. [Pg.162]

Avogadro s number Cylindrical coordinates Cartesian coordinates Concentration Events... [Pg.222]

For the iron(II) pocket porphyrins, the coordination state of the iron depended on the size of the pocket. Visible absorption and MCD spectral data showed that Fe (Poc-Piv) derived from 171a remained five coordinate even in the presence of excess base. Although the medium and large size pockets showed increasing six-coordination, concentration ranges could be determined within which five-coordinate iron(II) was the dominant species. The O2 and CO binding of the pocket and picket-fence porphyrins were comparedWhile the O2 affinities for both systems were similar, the pocket porphyrins showed a reduced CO affinity. Since electronic and solvent effects were similar in the two model systems, the reduction in CO affinity was attributed to the steric hindrance of the cap which distorted the Fe-C-0 unit from linearity. [Pg.167]

Fig. 2.12 Cathodic chronopotentiometric wave of reduction of Ge(IV) in molten NaF-KF-K2GeFg plotted in improved semi-logarithmic coordinates. Concentration of Ge 0.75 x 10 " mol cm, current density 3 x 10 A cm , temperature 750 °C [13]... Fig. 2.12 Cathodic chronopotentiometric wave of reduction of Ge(IV) in molten NaF-KF-K2GeFg plotted in improved semi-logarithmic coordinates. Concentration of Ge 0.75 x 10 " mol cm, current density 3 x 10 A cm , temperature 750 °C [13]...
Finally, the concentrated localized AE events are represented on the monitor in the form of a histogram "number of localized AE events vs axial coordinate", which is automatically updated at user-defined time intervals. [Pg.69]

In this section we concentrate on the electronic and vibrational parts of the wavefimctions. It is convenient to treat the nuclear configuration in temis of nomial coordinates describing the displacements from the equilibrium position. We call these nuclear nomial coordinates Q- and use the symbol Q without a subscript to designate the whole set. Similarly, the symbol v. designates the coordinates of the th electron and v the whole set of electronic coordinates. We also use subscripts 1 and ii to designate the lower and upper electronic states of a transition, and subscripts a and b to number the vibrational states in the respective electronic states. The total wavefiinction f can be written... [Pg.1127]

Laser Raman diagnostic teclmiques offer remote, nonintnisive, nonperturbing measurements with high spatial and temporal resolution [158], This is particularly advantageous in the area of combustion chemistry. Physical probes for temperature and concentration measurements can be debatable in many combustion systems, such as furnaces, internal combustors etc., since they may disturb the medium or, even worse, not withstand the hostile enviromnents [159]. Laser Raman techniques are employed since two of the dominant molecules associated with air-fed combustion are O2 and N2. Flomonuclear diatomic molecules unable to have a nuclear coordinate-dependent dipole moment caimot be diagnosed by infrared spectroscopy. Other combustion species include CFl, CO2, FI2O and FI2 [160]. These molecules are probed by Raman spectroscopy to detenuine the temperature profile and species concentration m various combustion processes. [Pg.1215]

In this section, we concentrate on the relationship between diffraction pattern and surface lattice [5], In direct analogy with the tln-ee-dimensional bulk case, the surface lattice is defined by two vectors a and b parallel to the surface (defined already above), subtended by an angle y a and b together specify one unit cell, as illustrated in figure B1.21.4. Withm that unit cell atoms are arranged according to a basis, which is the list of atomic coordinates within drat unit cell we need not know these positions for the purposes of this discussion. Note that this unit cell can be viewed as being infinitely deep in the third dimension (perpendicular to the surface), so as to include all atoms below the surface to arbitrary depth. [Pg.1767]

It is convenient to analyse tliese rate equations from a dynamical systems point of view similar to tliat used in classical mechanics where one follows tire trajectories of particles in phase space. For tire chemical rate law (C3.6.2) tire phase space , conventionally denoted by F, is -dimensional and tire chemical concentrations, CpC2,- are taken as ortliogonal coordinates of F, ratlier tlian tire particle positions and velocities used as tire coordinates in mechanics. In analogy to classical mechanical systems, as tire concentrations evolve in time tliey will trace out a trajectory in F. Since tire velocity functions in tire system of ODEs (C3.6.2) do not depend explicitly on time, a given initial condition in F will always produce tire same trajectory. The vector R of velocity functions in (C3.6.2) defines a phase-space (or trajectory) flow and in it is often convenient to tliink of tliese ODEs as describing tire motion of a fluid in F with velocity field/ (c p). [Pg.3055]

This section attempts a brief review of several areas of research on the significance of phases, mainly for quantum phenomena in molecular systems. Evidently, due to limitation of space, one cannot do justice to the breadth of the subject and numerous important works will go unmentioned. It is hoped that the several cited papers (some of which have been chosen from quite recent publications) will lead the reader to other, related and earlier, publications. It is essential to state at the outset that the overall phase of the wave function is arbitrary and only the relative phases of its components are observable in any meaningful sense. Throughout, we concentrate on the relative phases of the components. (In a coordinate representation of the state function, the phases of the components are none other than the coordinate-dependent parts of the phase, so it is also true that this part is susceptible to measurement. Similar statements can be made in momentum, energy, etc., representations.)... [Pg.101]

Some of these have already been noted as 2-coordinate and linear, for example [AgfCN) ]". [Ag(NH3)2]+. [AgfS Oj)] ". Silver(I) halides dissolve in concentrated aqueous halide solutions to give complexes [AgX ]", [AgXj]. for example [AgClj] . [Pg.430]

On the basis of the studies described in the preceding chapters, we anticipated that chelation is a requirement for efficient Lewis-acid catalysis. This notion was confirmed by an investigation of the coordination behaviour of dienophiles 4.11 and 4.12 (Scheme 4.4). In contrast to 4.10, these compounds failed to reveal a significant shift in the UV absorption band maxima in the presence of concentrations up to one molar of copper(ir)nitrate in water. Also the rate of the reaction of these dienophiles with cyclopentadiene was not significantly increased upon addition of copper(II)nitrate or y tterbium(III)triflate. [Pg.110]

The design of a collaborative test must provide the additional information needed to separate the effect of random error from that due to systematic errors introduced by the analysts. One simple approach, which is accepted by the Association of Official Analytical Chemists, is to have each analyst analyze two samples, X and Y, that are similar in both matrix and concentration of analyte. The results obtained by each analyst are plotted as a single point on a two-sample chart, using the result for one sample as the x-coordinate and the value for the other sample as the -coordinate. ... [Pg.688]

Until now we have been discussing the kinetics of catalyzed reactions. Losses due to volatility and side reactions also raise questions as to the validity of assuming a constant concentration of catalyst. Of course, one way of avoiding this issue is to omit an outside catalyst reactions involving carboxylic acids can be catalyzed by these compounds themselves. Experiments conducted under these conditions are informative in their own right and not merely as means of eliminating errors in the catalyzed case. As noted in connection with the discussion of reaction (5.G), the intermediate is stabilized by coordination with a proton from the catalyst. In the case of autoprotolysis by the carboxylic acid reactant, the rate-determining step is probably the slow reaction of intermediate [1] ... [Pg.288]

The miscibility gap becomes progressively more lopsided as n increases. This means that c occurs at lower concentrations and that the tie line coordinates—particularly for the more dilute phase-are lower for large n. [Pg.535]

The physical and chemical properties are less well known for transition metals than for the alkaU metal fluoroborates (Table 4). Most transition-metal fluoroborates are strongly hydrated coordination compounds and are difficult to dry without decomposition. Decomposition frequently occurs during the concentration of solutions for crysta11i2ation. The stabiUty of the metal fluorides accentuates this problem. Loss of HF because of hydrolysis makes the reaction proceed even more rapidly. Even with low temperature vacuum drying to partially solve the decomposition, the dry salt readily absorbs water. The crystalline soflds are generally soluble in water, alcohols, and ketones but only poorly soluble in hydrocarbons and halocarbons. [Pg.167]


See other pages where Coordinate concentration is mentioned: [Pg.174]    [Pg.1206]    [Pg.529]    [Pg.1205]    [Pg.249]    [Pg.28]    [Pg.191]    [Pg.356]    [Pg.174]    [Pg.1206]    [Pg.529]    [Pg.1205]    [Pg.249]    [Pg.28]    [Pg.191]    [Pg.356]    [Pg.76]    [Pg.491]    [Pg.773]    [Pg.1933]    [Pg.2064]    [Pg.2243]    [Pg.2308]    [Pg.2787]    [Pg.3057]    [Pg.692]    [Pg.371]    [Pg.178]    [Pg.273]    [Pg.592]    [Pg.69]    [Pg.83]    [Pg.153]    [Pg.1170]    [Pg.283]    [Pg.575]    [Pg.205]    [Pg.40]    [Pg.65]    [Pg.259]   
See also in sourсe #XX -- [ Pg.20 , Pg.21 , Pg.22 , Pg.23 , Pg.24 , Pg.25 , Pg.67 ]




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Concentration general coordinates

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