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Mass approaches

When time approaches infinity, the cumulative mass approaches a linear function of time ... [Pg.60]

In the calculation results (Fig. 26.6), the initial segment of the path is marked by the disappearance of the amorphous silica as it reacts to form cristobalite. The amorphous silica is almost completely consumed after about 10000 years of reaction. The mineral s mass approaches zero asymptotically because (as can be seen in Equation 26.1) as its surface area As decreases, the dissolution rate slows proportionately. During the initial period, only a small amount of quartz forms. [Pg.398]

Chandrasekhar, S. (1964). The dynamical instability of gaseous masses approaching the Schwarz-schild limit in general relativity. Astrophys. J., 140 417—433. [Pg.22]

The steady-state temperature of the fiberglass process line can be estimated with a lumped mass approach by iteratively solving Equation (5-22) for Tj. Assume the ambient and initial target temperature to be 20°C (293 K) and a nominal heat transfer coefficient of 0.015 kW/m K. [Pg.98]

These approximations are reliable apart from when a(r) is very small, as Figure 18.13 confirms. As a(r) —> 0, the remaining mass approaches 1, which is the correct (but practically useless) limit for end-chain scission of a population with initially infinite degree of polymerization. For a realistic population with initially finite degree of polymerization, this is unhelpful as the correct limit is 1 - x/n. It may be shown that when 0(a(r)) > 1 In, and n is large, the initial distribution of polymer molecules has little effect on the frequencies and the approximations remain valid. [Pg.496]

Attempts to quantitatively explain the energetic position of the quantum well emission using a simple effective-mass approach have been fairly successful for narrow quantum wells with Lz < 3 nm [9]. For wide wells, however, some groups even observe two emission lines, which were initially interpreted in terms of a defect-related transition at lower energies and a band-to-band transition at higher energies [10]. [Pg.520]

More traditional approaches to treating the age of groundwater systems have tended to overemphasize the advective-dominated portions of the system. The age mass approach forces consideration of both advective and diffusive transport through the entire system. This is nicely illustrated by the observation of Bethke and Johnson (2002b) that the accumulation of age... [Pg.2711]

We consider nanocrystals as spherical QDs and use the effective mass approach developed in [2]. The spin-orbit interaction is neglected in the consideration. The details of the approximation are given below. [Pg.64]

To multiplex the MASS approach and further increase the throughput, it... [Pg.73]

Tiller et al. [289] reported the use of accurate LC-MS/MS data from a Q-TOF system as a first-line approach for metabolite identification studies in the discovery phase of the drug development. In this approach, first, the MS/MS spectrum of the parent compound under conditions of high mass resolution is obtained in order to support the proposed fragmentation pattern by elemental composition data. In the next step of the accurate mass approach to metabolite identification, the in vitro samples of drug candidates from incubations in liver microsomal preparations or hepatocytes are analyzed by LC-MSE on the Q-TOF mass spectrometer. Data are... [Pg.175]

The highest level of protein structure is the association of proteins into macromolecular assemblies. Typically, such structures are very large, exceeding 1 mDa in mass, approaching 30-300 nm in size, and containing tens to hundreds of polypeptide chains, as well as nucleic acids in some... [Pg.66]

Blom, K.F., Average mass approach to stable isotope dilution mass spectrometry. Mass Spectrom., 22, 530-533 (1987). [Pg.48]

This generator was based on a suspended, proof-mass approach that used concatenated roll transducers. [Pg.82]

Equation (7-9) holds in the absence of main-chain scission, i.e. at d>(S)=0. In this case, the reciprocal molar mass approaches infinity at the gel dose, i.e. [Pg.195]

Although the idea of dynamically similar but thermodynamically different polymers seems at first to be a rather contrived and artifical model, there is one class of systems that are actually quite close realisations of it. These are pairs of isotopically substituted polymers of high relative molecular mass, approaching those relative molecular masses for which phase separation would take place. The composition dependence of the mutual diffusion coefficient for such diffusion couples has been measured directly for interfaces between polystyrene and deuterated polystyrene (Green and Doyle 1987) and the results are in excellent agreement with theory (figure 4.21). This also means that we can use equation (4.4.7) to check whether isotopic labelling is likely to perturb an attempted self-diffusion measurement. [Pg.159]

Irvars Diego Mas, Pierce Matthew E, Darcel Caroline, etc. 2011. The synthetic rock mass approach for jointed rock mass modeling. IntJ.Rock Meek Min. Sci, 48 219-244. [Pg.683]

One must remember that nothing happens to the parts alone. These cleaning steps are applied to the parts and the basket in which they are contained. If the basket blocks fluid flow because it has too small an open area, the parts won t be well contacted with solvent. If it has a thermal mass approaching that of the parts, hot solvent vapor will condense on its surfaces instead of those of the parts. This is why it is important to choose a parts basket which has these two characteristics (1) small (thin) support elements so the open area is as large as possible to not block fluid flow, and (2) as little metal as possible to minimize thermal mass so that heat transfer potential is not wasted (in Box 1.4 is described a situation where the opposite is desired). These characteristics minimize loss of the treatment effect by not "wasting" it on the parts basket. [Pg.9]

Consider a polymer chain that can be positioned at various distances, z, aw ay from an impenetrable surface. As the chain s center of mass approaches the surface, some of the chain s extended conformations are not physically viable because those conformations would pass through the surface (see Figure 33.2). Because the conformational entropy decreases as the chain approaches the surface, the conformational free energy F increases, and this can be described as a repulsive force, / = -dF/dz, between the surface and the chain. [Pg.631]

Shahidi-Latham, S.K., Dutta, S.M., Prieto Conaway, M.C. and Rndewicz, P.J. (2012) Evalnation of an accurate mass approach for the simnltaneons detection of drug and metabolite distributions via whole-body mass speetrometrie imaging. Anal. Chem. 84, 7158-7165. [Pg.50]

The core holes responsible are believed to be formed as a result of sufficiently energetic atomic collisions occurring within the collision cascade. As a result, this should display a primary ion energy threshold as is indeed observed ( 900 eV for Ar impact on Aluminum surfaces). The threshold is present as the energy transfer from atoms/ions involved in collisions with electrons is an inefficient process. Also of note is the fact that collision threshold energy scales with the masses of the colliding partners. Indeed, those between the atoms of the same mass, otherwise referred to as symmetric collisions, yield the lowest threshold. Collisions between atoms of different masses are referred to as asymmetric collisions. This variation can be traced back to the fact that the efficiency of momentum transfer increases as the atomic masses approach each other (see Section 3.2.1.1 and relations contained within). [Pg.129]

Local Power Per Mass Approach. Davies (1987) showed that values of dmax for a wide variety of dispersion devices could be correlated with local power per mass if a rough estimate of Smax/ avg could be obtained. By extending the ideas of McManamey (1979), he argued that this could be accomplished by assuming that all the power is dissipated in a localized, device-specific volume. The results of his analysis of literature data for dilute inviscid dispersed phases, corrected for interfacial tension, are shown in Figure 12-11. The slope of the line bounding the data is as predicted by eq. (12-21). The rotor-stator data discussed above would lie between the data for agitated vessels and liquid whistles. [Pg.666]

A more plausible interpretation is that the motion of ponderous objects, projected into tangent three-dimensional space, differs imperceptibly from four-dimensional reality in the local environment where a classical description suffices. It only becomes an issue for fast-moving objects and where particle mass approaches zero. The real meaning of both relativity and quantum theory is obscured by their formulation as alternatives to Newtonian mechanics that kick in at some classical limit. [Pg.36]


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See also in sourсe #XX -- [ Pg.402 , Pg.412 , Pg.413 ]




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