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Complex elements

It is convenient, for simple systems, to have explicit expressions for equation (B2.4.17). Since the original matrix is non-Hemiitian, the matrix fomied by the eigenvectors will not be unitary, and will have four independent complex elements. Let them be a, b, c and d, so that U is given by equation (B2.4.20). [Pg.2097]

Assay of beryUium metal and beryUium compounds is usuaUy accompHshed by titration. The sample is dissolved in sulfuric acid. Solution pH is adjusted to 8.5 using sodium hydroxide. The beryUium hydroxide precipitate is redissolved by addition of excess sodium fluoride. Liberated hydroxide is titrated with sulfuric acid. The beryUium content of the sample is calculated from the titration volume. Standards containing known beryUium concentrations must be analyzed along with the samples, as complexation of beryUium by fluoride is not quantitative. Titration rate and hold times ate critical therefore use of an automatic titrator is recommended. Other fluotide-complexing elements such as aluminum, sUicon, zirconium, hafnium, uranium, thorium, and rate earth elements must be absent, or must be corrected for if present in smaU amounts. Copper-beryUium and nickel—beryUium aUoys can be analyzed by titration if the beryUium is first separated from copper, nickel, and cobalt by ammonium hydroxide precipitation (15,16). [Pg.68]

A linear coordinate transformation may be illustrated by a simple two-dimensional example. The new coordinate system is defined in term of the old by means of a rotation matrix, U. In the general case the U matrix is unitary (complex elements), although for most applications it may be chosen to be orthogonal (real elements). This means that the matrix inverse is given by transposing the complex conjugate, or in the... [Pg.310]

Figure 2. Vapor pressures of bromine/quaternary ammonium salt complexes elemental Br2, Me4N+ Br, MEMBr, Oct,MeN Cl. From Ref. [59J. Figure 2. Vapor pressures of bromine/quaternary ammonium salt complexes elemental Br2, Me4N+ Br, MEMBr, Oct,MeN Cl. From Ref. [59J.
Number of real parameters contained in complex P The P matrix, made of complex elements, pv, may be written as... [Pg.141]

After factoring of the P matrix, Pecora considers that the constraints are summarized by the equation CC+ = and is completely determined by . This analysis, too, is based on counting the number of complex conditions on the complex elements of C. [Pg.147]

In aU physical applications, although both H and U may contain compLex elements, the eigenvalues K are real (see Section 7.2). Equation (66) can be... [Pg.88]

These complex elements expand the function of this neural adherens junction . [Pg.116]

Table 16.1 gives a FORTRAN program which generates the multivariable Nyquist plot for the Wood and Berry column. The subroutines given in Chap. 15 are used for manipulating the matrices with complex elements. The subroutines PROCTF and FEEDBC calculate the and complex numbers at each value of frequency. A general process transfer function is used for each of the elements in the matrix that has the form... [Pg.565]

This form of nucleosynthesis, known as the r process (or rapid process), is assumed to produce the more complex elements existing in nature, those lying well beyond iron, according to the following series of reactions ... [Pg.165]

The flow-mixing transfer functions Gi(s) and G2(s) can be chosen to represent any desired parallel or series combinations of PFRs and CSTRs or other more complex elements. Making a mass balance at the entry flowmixing point... [Pg.258]

Fifteen to twenty billion years ago, the universe arose as a cataclysmic eruption of hot, energy-rich subatomic particles. Within seconds, the simplest elements (hydrogen and helium) were formed. As the universe expanded and cooled, material condensed under the influence of gravity to form stars. Some stars became enormous and then exploded as supernovae, releasing the energy needed to fuse simpler atomic nuclei into the more complex elements. Thus were produced, over billions of years, the Earth itself and the chemical elements found on the Earth today. About four billion years ago,... [Pg.1]

The simplest symmetry operations and elements needed to describe unitcell symmetry are translation, rotation (element rotation axis), and reflection (element mirror plane). Combinations of these elements produce more complex symmetry elements, including centers of symmetry, screw axes, and glide planes (discussed later). Because proteins are inherently asymmetric, mirror planes and more complex elements involving them are not found in unit cells of proteins. All symmetry elements in protein crystals are translations, rotations, and screw axes, which are rotations and translations combined. [Pg.62]

Inspection of Table II shows that a variety of iodine products are formed with the iodine in several oxidation states. Thus fixation materials with iodine as complexed elemental iodine, iodide, and iodate, must be evaluated, and the solid fixation matrix selected must be able to accept a variety of materials. [Pg.361]

In this respect, we note that also earlier [318,618] the template electrosynthesis was used to produce phthalocyanine complexes elemental metals or dissolved metal salts were used as a source of metal center (see details in Sec. 5.1). [Pg.267]

Our purpose is to construct an analogous parameterization for the 50(4) group. In order to reach this goal we mention that there exists a similar homomorphism between the 50(2) group of 2 x 2 unitary matrices with complex elements with the unit determinant and the 50(3) group. The correspondence establishes as follows for a rotation 1Z in the three dimensional space one can choose a quaternion representation r = (rn.r). This quaternion is normalized and it defines a 2 x 2 matrix ... [Pg.223]

This is the famous Saha-Langmuir equation. In it, g+/g0 is the ratio of the statistical weights of the ionic and atomic states, is the work function of the surface, / is the first ionization potential of the element in question, k is the Boltzmann constant, and T is the absolute temperature. Note that gjg0 is close to 1 for electronically complex elements for simpler elements it can take on a variety of values depending on how many electronic states can be populated in the two species for alkali atoms, for example, it is often Vi. Attainment of thermodynamic equilibrium was assumed in the derivation of this equation, and it is applicable only to well-defined surfaces. [Pg.4]

Law Five (ab)c = a(bc) (associative law of multiplication). The two rules are adopted to eliminate ambiguous cases. Rule 1 complex elements must be broken down into their fundamental counterparts and then reacted and rule 2 a reaction in a series of reactions joins the new polymer to the next element on the right. Thus we have Equations 28, 29, 30, 31, and 32. Finally, in conformity with Law Five, we have Equations 33 and 34. The chemical structures associated with Equations 28, 29, and 30 are shown in Figure 2. [Pg.608]

There are two realizations of the abstract Hilbert space which are frequently used in physics the sequential Hilbert space J( 0, and the L2 Hilbert space. The sequential Hilbert space Jf0 consists of all infinite column vectors c = ct with complex elements having a finite norm c, so that... [Pg.99]

It should further be observed that the set (pa for all values of m and rational values of the complex elements in the column vectors a form an enumerable set Jf", which is everywhere dense in the entire Hilbert space, including the domain D U l) and its complement C(l7 1). We note that all numerical applications are, in fact, based on this theorem. [Pg.117]

Hence even the matrix t is a symmetric matrix with complex elements. [Pg.133]

We note finally that, in the numerical studies of the complex symmetric operators Tu and Tueff, it is usually convenient to use orthonormal basis sets which are real, since the associated matrices will then automatically be symmetric with complex elements. In the case of a truncated basis of order m, most of the eigenvalues will usually turn out to be complex, but we observe that one has to study their behaviour when m goes to infinity and the set becomes complete, before one can make any definite conclusions as to the existence of true complex eigenvalues to Tu and Tuefj, respectively. The connection between the results of approximate numerical treatments and the exact theory is still a very interesting but mostly unsolved problem. [Pg.216]


See other pages where Complex elements is mentioned: [Pg.1728]    [Pg.17]    [Pg.69]    [Pg.185]    [Pg.109]    [Pg.141]    [Pg.39]    [Pg.27]    [Pg.85]    [Pg.71]    [Pg.78]    [Pg.175]    [Pg.144]    [Pg.134]    [Pg.407]    [Pg.11]    [Pg.18]    [Pg.3]    [Pg.310]    [Pg.182]    [Pg.64]    [Pg.96]    [Pg.98]    [Pg.159]    [Pg.194]    [Pg.215]    [Pg.219]    [Pg.65]   
See also in sourсe #XX -- [ Pg.41 ]




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