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Quantities directional total

In a purely chemical approach to how reactions take place, all of these factors come together specifically, the rate is related to the total energy used and released, the energy of activation required, steric effects, and the types of bonds being broken and formed. For this reason, it is most common to measure the energy and rate quantities directly for the conditions of the reaction. Because of the complexity of soil, it is even more important to measure these directly. [Pg.80]

Directional total quantities average the radiation over all wavelengths and describe the dependence on the directions in the hemisphere. [Pg.505]

Here d2radiation flow emitted by the surface element into the solid angle element dee in the direction of the angle /3 and total intensity L has units W/m2sr it belongs to the directional total quantities and represents the part of the emissive power falling into a certain solid angle element. [Pg.510]

The total intensity L(f3,ip,T) describes the directional dependency (distribution over the solid angles of the hemisphere) of the radiated energy at all wavelengths (directional total quantity). [Pg.511]

The incident intensity K(f3,(p) describes the directional distribution of the incident radiation flow (directional total quantity). [Pg.517]

Unfortunately, the minimum size of a-Si cluster that can be amplified by this method still remains unclear as we have not been able to measure effectively the too small total mass of the deposits. The number density of silver particles is, therefore, the only quantity directly accessible in this experiment, but the number density of Si nuclei and its variation with deposition parameters should be properly reflected on those of the developed silver particles. [Pg.342]

Because gel acts as a molecular sieve, there is a direct correlation between elution volume (Ve, the volume of solvent required to elute the protein from the column since it first contacted the gel) and molecular weight. When gel-filtration chromatography is used to determine molecular weight, the gel column must be carefully calibrated. This is accomplished by careful measurement of several quantities. The total column volume V, is equal to the sum of the volume occupied by the gel Vg and the void volume Vc, which is the volume occupied by the solvent molecules ... [Pg.159]

This relation is known as Kirchhoff s law. Equation 7.27 may be substituted into the various relationships for the integrated emissivity or absorptivity. However, it does not follow that such quantities as directional total, hemispherical-spectral, or hemispherical total emissivity and absorptivity are necessarily equal. In fact, the integrated properties are only equal if certain restrictions are met. These are given in Table 7.1. [Pg.532]

In the control test, the enzyme having been immediately destroyed, the predpitate, weighing 338 mg. represents the quantity of total albumin contained in each tube. In test No. 2, the papain has been left i minute in direct contact with the albumin, then rapidly brought to 100 . The duration of heating, which has been from 10 to 20 seconds, has been quite sufiSd t to bring abouta maximum effect, ii 2 mg. of dissolved albumin... [Pg.441]

The results show that is the same for a-Ce and y-Ce and hence that changes in the n are directly related to changes in Values of the 4f-occupation (Allen et al. 1983) derived from BIS experiments on the basis of the Gunnarsson-Schonhammer (1983) (G-S) model are 1.0 for y-Ce and 0.85 for a-Ce. In our case, n is derived in a simple way by finding the minimum of the total energy curve and is different from the 4f-occupation number in the G-S model, which is the eigenvalue of a number operator in their model Hamiltonian. Since our basic quantities are total energies, a direct comparison of our results with the experimental spectra is more appropriate than is a comparison with the G-S values. [Pg.205]

Quantity Direct Complex Total van der Waals Bulka... [Pg.361]

The B.P. estimation of total balsamic acids is due to Cocking. The acids from the saponified balsams are converted into the corresponding magnesium salts and the salts of the balsamic acids are separated from the salts of the resin acids by filtration and from aromatic alcohols by extraction with sodium bicarbonate. The B.P. quantities directed to be used must be adhered to and the manipulative details must be closely followed to prevent precipitation of gummy matter and formation of clots. [Pg.643]

To determine moderate amounts of Cr(III) and Cr(VI) in samples that have both oxidation states present, Cr(VI) is analyzed by direct titration in one sample, and the total chromium is found in a second sample after oxidation of the Cr(III). The Cr(III) concentration is determined as the difference. Trace quantities of Cr(VI) in Cr(III) compounds can be detected and analyzed by (3)-diphenylcarbazide. Trace quantities of Cr(III) in Cr(VI) may be detected and analyzed either photometrically (102) or by ion chromatography using various modes of detection (103). [Pg.141]

The acetone supply is strongly influenced by the production of phenol, and so the small difference between total demand and the acetone suppHed by the cumene oxidation process is made up from other sources. The largest use for acetone is in solvents although increasing amounts ate used to make bisphenol A [80-05-7] and methyl methacrylate [80-62-6]. a-Methylstyrene [98-83-9] is produced in controlled quantities from the cleavage of cumene hydroperoxide, or it can be made directly by the dehydrogenation of cumene. About 2% of the cumene produced in 1987 went to a-methylstyrene manufacture for use in poly (a-methylstyrene) and as an ingredient that imparts heat-resistant quaUties to polystyrene plastics. [Pg.364]

The second term in brackets in equation 36 is the separative work produced per unit time, called the separative capacity of the cascade. It is a function only of the rates and concentrations of the separation task being performed, and its value can be calculated quite easily from a value balance about the cascade. The separative capacity, sometimes called the separative power, is a defined mathematical quantity. Its usefulness arises from the fact that it is directly proportional to the total flow in the cascade and, therefore, directly proportional to the amount of equipment required for the cascade, the power requirement of the cascade, and the cost of the cascade. The separative capacity can be calculated using either molar flows and mol fractions or mass flows and weight fractions. The common unit for measuring separative work is the separative work unit (SWU) which is obtained when the flows are measured in kilograms of uranium and the concentrations in weight fractions. [Pg.81]

In addition to ethylene oxide, carbon dioxide, and water, small quantities of acetaldehyde and traces of formaldehyde are also produced in the process. They generally total less than 0.2% of the ethylene oxide formed. Acetaldehyde is most likely formed by isomerization of ethylene oxide, whereas formaldehyde is most likely formed by direct oxidation of ethylene (108). [Pg.455]

In spin relaxation theory (see, e.g., Zweers and Brom[1977]) this quantity is equal to the correlation time of two-level Zeeman system (r,). The states A and E have total spins of protons f and 2, respectively. The diagram of Zeeman splitting of the lowest tunneling AE octet n = 0 is shown in fig. 51. Since the spin wavefunction belongs to the same symmetry group as that of the hindered rotation, the spin and rotational states are fully correlated, and the transitions observed in the NMR spectra Am = + 1 and Am = 2 include, aside from the Zeeman frequencies, sidebands shifted by A. The special technique of dipole-dipole driven low-field NMR in the time and frequency domain [Weitenkamp et al. 1983 Clough et al. 1985] has allowed one to detect these sidebands directly. [Pg.116]

Air is usually the basic load component to an ejector, and the quantities of water vapor and/or condensable vapor are usually directly proportional to the air load. Unfortunately, no reliable method exists for determining precisely the optimum basic air capacity of ejectors. It is desirable to select a capacity which minimizes the total costs of removing the noncondensable gases which accumulate in a process vacuum system. An oversized ejector costs more and uses unnecessarily large quantities of steam and cooling water. If an ejector is undersized, constant monitoring of air leaks is required to avoid costly upsets. [Pg.198]


See other pages where Quantities directional total is mentioned: [Pg.2110]    [Pg.120]    [Pg.166]    [Pg.79]    [Pg.183]    [Pg.173]    [Pg.146]    [Pg.120]    [Pg.120]    [Pg.259]    [Pg.2110]    [Pg.170]    [Pg.241]    [Pg.970]    [Pg.207]    [Pg.378]    [Pg.202]    [Pg.203]    [Pg.415]    [Pg.163]    [Pg.94]    [Pg.514]    [Pg.1812]    [Pg.2221]    [Pg.185]    [Pg.131]    [Pg.331]    [Pg.93]    [Pg.399]    [Pg.53]    [Pg.252]    [Pg.437]    [Pg.35]   
See also in sourсe #XX -- [ Pg.505 ]




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