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Elements density

In the North American market, water heaters are almost always made with the cold water inlet and hot water outlet lines coming out of the top of the tank. The hot water outlet opens right into the top of the tank and so draws off the hottest water. The hot water has risen to the top of the tank because of its lower density. The cold water on the inlet side is directed to the bottom of the tank by a plastic dip-tube. In some models the dip-tube is curved or bent at the end to increase the turbulence at the bottom of the tank. This is to keep any sediment from settling on the bottom of the tank. As sediment— usually calcium carbonate or lime—precipitated out of the water by the increased temperature builds up, it will increase the thermal stress on the bottom of a gas-fired water heater and increase the likelihood of tank failure. On electric water heaters the sediment builds up on the surface of the elements, especially if the elements are high-density elements. Low-density elements spread the same amount of power over a larger surface of the element so the temperatures are not as high and lime doesn t build up as quickly. If the lower elements get completely buried in the sediment, the element will likely overheat and burn out. [Pg.1216]

From these data one can conclude that antiresorptives are capable of inducing striking reductions in fracture risk with limited changes in bone density. Therefore, other factors than bone density should explain their efficacy. Bone quality is the term that encompasses all the non-bone-density elements implied in bone strength, as previously discussed. [Pg.206]

The M-NM transition has been a topic of interest from the days of Sir Humphry Davy when sodium and potassium were discovered till then only high-density elements such as Au, Ag and Cu with lustre and other related properties were known to be metallic. A variety of materials exhibit a transition from the nonmetallic to the metallic state because of a change in crystal structure, composition, temperature or pressure. While the majority of elements in nature are metallic, some of the elements which are ordinarily nonmetals become metallic on application of pressure or on melting accordingly, silicon is metallic in the liquid state and nonmetallic in the solid state. Metals such as Cs and Hg become nonmetallic when expanded to low densities at high temperatures. Solutions of alkali metals in liquid ammonia become metallic when the concentration of the alkali metal is sufficiently high. Alkali metal tungsten bronzes... [Pg.346]

Let us summarize. The calculation of Cl first anharmonicities requires no storage or transformation of second and third derivative two-electron integrals, but the full set of first derivative MO integrals is needed. One must construct and transform one set of effective density elements for third derivative integrals and 3M — 6 sets of effective densities for second derivative integrals. In addition to the 3N — 6 MCSCF orbital responses k(1) and the Handy-Schaefer vector Cm needed for the Hessian, the first anharmonicity requires the solution of 3JV — 6 response equations to obtain (1). [Pg.210]

In these expressions differentiation and one-index transformations refer to the g integrals only of the Fock matrix [Eqs. (235) and (236)], treating the t elements as densities. The Fock matrix density elements in (Dj 1 and to the contravariant representation. If first derivative integrals in the MO basis is reduced to two occupied and two unoccupied indices (Handy et al., 1986). Note that 7] + T2 [Eqs. (257) and (258)] has the same structure as the <2) part of the MRCI Hessian (129). [Pg.225]

In the first expression the integrals are in the covariant AO representation (in which they are calculated), and the one-index transformed density elements are in the contravariant representation (obtained from the MO basis in usual one- and two-electron transformations). The second expression is useful whenever the transformation matrix is calculated directly in the covariant AO representation and requires the transformation of the Fock matrix to the contravariant representation. The last expression is convenient when the number of perturbations is large, since it avoids the transformation of the covariant AO Fock matrix to the MO or contravariant AO representations. [Pg.241]

The assumption of fast attainment of equilibrium for the off-diagonal elements makes it possible for us to set dp12(t)/dt = 0 in Eq. (8) and dp2 (t)/dt = 0 in Eq. (9). This is the famous Smoluchowski approximation [9]. The off-diagonal density elements play the same role as the velocity of the Brownian particle [9], and their time derivatives are assumed to vanish. This allows us to express pj 2 and p2 as a function of the diagonal density matrix elements,... [Pg.364]

Of course the diagonal density elements pj 1 (f), p22(t) are identified with the probabilities p (t) and pi(t), respectively. One of the major tasks of this review is to point out the difficulties that are currently met with the extension of this interpretation to the case where the Markov condition of the ordinary Pauli master equation does not apply. [Pg.364]

At normal temperature and pressure, hydrogen is a colorless, odorless gas with no toxic effects. It is the lowest density element, whilst also having a high diffusion... [Pg.5]

What you monitor Particles, moisture, viscosity, temperature, additives, oxidation, AN/BN, soot, glycol, FTIR, RPVOT Wear debris density, temperature, particle count, moisture, elemental analysis, viscosity, analytical ferrography Wear debris, elemental analysis, moisture, particle count, temperature, viscosity, anal5fiical ferrography, vibration analysis Elemental analysis, analytical ferrography, vibration analysis, temperature Analytical ferrography, ferrous density, elemental analysis... [Pg.1520]

Figure 7. Transition densities calculated for a Bchl molecule and a carotenoid. Density elements, containing charge qi, qj, and so on, are depicted together with their corresponding separation fy. Summing the Coulombic interaction between all such elements gives the total Coulombic interaction, which, according to the TDC method, promotes energy transfer. See color insert. Figure 7. Transition densities calculated for a Bchl molecule and a carotenoid. Density elements, containing charge qi, qj, and so on, are depicted together with their corresponding separation fy. Summing the Coulombic interaction between all such elements gives the total Coulombic interaction, which, according to the TDC method, promotes energy transfer. See color insert.
Having discussed the scattering density element of the Debye equation, the geometrical term can now be considered. Sections 2.4, 2.5 and 2.6 deal with only particles that have a uniform scattering density within their surface boundaries. Density fluctuations are dealt with in section 2.7. In a small Q range close to zero Q, the Debye equation is reduced to a simple form, a Gaussian curve. This is shown by the expansion of the term containing sin(rQ)/rg as a power series ... [Pg.160]

Electron Boiling Density Element Configuration Point (K) (g/L) Atomic Radius (A) h (kj/mol)... [Pg.276]

Figure 5.3, Relationship between exposure ( ) and developed silver density (D). The continuous curve illustrates the basic sensitometry obtained in negative-working systems. Increasing exposure results in increasing developed (optical) density (elemental silver or image dye in the case of colour systems). The dotted curve illustrates positive-working sensitometry, where increasing exposure results in decreasing developed density... Figure 5.3, Relationship between exposure ( ) and developed silver density (D). The continuous curve illustrates the basic sensitometry obtained in negative-working systems. Increasing exposure results in increasing developed (optical) density (elemental silver or image dye in the case of colour systems). The dotted curve illustrates positive-working sensitometry, where increasing exposure results in decreasing developed density...
Elenent Atom Densities Element Atom Densities cm ... [Pg.458]

In searching for new explosives one is most concerned with performance (detonation velocity and pressure), thermal properties, and sensitivity. Whether a new candidate explosive is ultimately widely used may well be determined by other factors, such as cost, toxicity, melting point, etc., but the initial research effort is guided by the trinity of performance, thermal stability, and sensitivity. This presents a difficult multifactoral problem in assessing the various molecular properties that contribute to each of these principal selection criteria. For instance, detonation velocity is affected by density, elemental composition, and heat of formation. These factors must be varied together in such a way as to maximize the combined effect on performance. [Pg.605]

The movement of the atom is defined by its momenta and spatial coordinates. These define what is known as the phase space. The minimum volume per representative point in phase space equals as follows from Heisenberg s uncertainty principle dx dpx h. The normalized space density element becomes... [Pg.113]

Explicit expressions for the electronic energy, gradient, and Hessian may be derived by inserting the electronic Hamiltonian in the form of equation (104) and invoking the anticommutation relations of the elementary operators. For the energy, we obtain an expression of the form of equation (29), where the density elements are given by ... [Pg.1168]

In second quantization, therefore, the density elements are expectation values of the excitation operators, the numerical values of which may be obtained by the repeated application of the anticommutation relations (equations 101-103). [Pg.1168]


See other pages where Elements density is mentioned: [Pg.450]    [Pg.314]    [Pg.79]    [Pg.220]    [Pg.231]    [Pg.197]    [Pg.206]    [Pg.206]    [Pg.209]    [Pg.214]    [Pg.222]    [Pg.237]    [Pg.450]    [Pg.434]    [Pg.3950]    [Pg.477]    [Pg.317]    [Pg.392]    [Pg.193]    [Pg.32]    [Pg.201]    [Pg.480]    [Pg.5083]    [Pg.40]    [Pg.27]    [Pg.98]    [Pg.13]    [Pg.72]    [Pg.477]    [Pg.1162]   
See also in sourсe #XX -- [ Pg.141 ]

See also in sourсe #XX -- [ Pg.141 ]

See also in sourсe #XX -- [ Pg.47 ]

See also in sourсe #XX -- [ Pg.47 ]

See also in sourсe #XX -- [ Pg.130 ]




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Density carbon family elements

Density halogen family elements

Density liquid elements and salts

Density matrices matrix elements

Density matrix diagonal elements

Density matrix elements

Density matrix elements master equation

Density matrix elements, transferability

Density metallic elements

Density nitrogen family elements

Density of Molten Elements and

Density of Molten Elements and Representative Salts

Density of elements

Density of the elements

Density operator matrix elements

Density oxygen family elements

Density rare earth elements

Density transition elements

Electron density matrix elements

Electron density matrix elements transferability

Element mass densities

Elemental data density

Elements of Electron Density Shape Analysis

Elements of density-functional theory

Local density functional Hamiltonian matrix elements

Quantum chemical methods density matrix elements

Solid Density of Selected Elements

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