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Specification of the problem

A leaded bronze is a more complex material than a lead fistula, as it is a Cu-Sn-Pb alloy. The two requirements are to relate the chemical states and concentrations of the elements present in the external layers to those in the bulk and to examine lateral inhomogeneity by comparison of XPS with SAM. Analysis of the microchemical composition of the original patina is also of interest. [Pg.857]

The bulk elemental compositions of the three bronzes as determined by ICP/EPMA are reported in Fig. 24. Trace elements at concentrations down to 0.01 wt.% [22] were also detected. Table 2 summarizes photoelectron BEs and Auger KEs for Cu, Sn and Pb, and the modified Auger parameter [23] for Cu, defined as aJu = BE(Cu 2/73/2) -1- KE(Cu L3VV). Cu was present as Cu+ at the surfaces (as-received condition) of all the bronzes, as indicated by a = 1849.1 0.1 eV, and confirmed by the line shape of the Cu 2/73/2. spectrum (Fig. 25), which lacked the shake-up structure characteristic of Cu- species 24]. Neither Sn nor Pb showed any variation in valence state as a function of bulk content, being always in the Sn and Pb forms, respectively. [Pg.857]

Although bronzes 1 and 3 contained similar bulk Pb contents, Pb was found by XPS on the surface only for bronze 1. Small quantities of chlorides and [Pg.857]

Compositional variations across the interface between the original patina and the bare surface of bronze 3 were also explored. In the SEM image in Fig. 31 points 1, 2 and 3 correspond to the bare surface, interface, and patina, re- [Pg.861]

38) with lateral resolutions of about 0.5 and 0.1 (itn, respectively. These tni-croanalytical results are of particular methodological relevance because they represent an improvement over EPMA mapping and perhaps anticipate an ever wider use of SAM analysis in the study of the surface microchemistry of metallurgical archaeomaterials. [Pg.868]


This simplification must be used with caution, of course, making sure that the specification of the problem does not determine the magnitude of the pressure gradient, but it is very useful in the important case of a coarsely porous catalyst pellet. [Pg.41]

Complete specification of the problem requires that boundary conditions be imposed at each end of the computational domain. At y = 0 we have... [Pg.408]

The two structures differ in only one place, the orientation at position 4. The numbering system is the same for both sfructures, so the proposed structure of galactose meets the specifications of the problem. [Pg.924]

Having established the formal specification of the problem-solving framework, the next goal is to establish how the solution of example problems can be turned into relevant problem-solving experience (Section III). [Pg.273]

Specification of the problem complete specification is essential for computer methods. [Pg.543]

SPECS Subroutine to read in the specifications of the problem pco2 = 1... [Pg.102]

The process sketched out in this section can be used to create an adsorber design. There are often times when one wants to examine the performance of an existing unit. When performance analysis is needed there are several alternatives. Depending on the specifics of the problem there may be an analytical solution for the adsorption problem and that may enable the creation of a satisfactory descrip-hon of the process to use in understanding phenomena that are observed in operation. [Pg.294]

The most important task in any automation problem is to provide an accurate and detailed specification of the problem. The person most able to tackle this task is the analyst. Very often he or she will have Httle, if any, experience in the general area of automation and computing. This chapter has tried to illustrate how an analyst, in consultation with a... [Pg.85]

Step 3 To evaluate the bulk flow term, we now must relate Wa to the concentration gradient utilizing the specification of the problem statement. For diffusion of almost all solutes through a liquid, the concentration of the diffusing species is considered dilute. For a dilute concentration of the diffusion solute, we have for constant total concentration. [Pg.694]

These setup files can also be exported from an existing model specification in ModKit+. In this case ModKit + acts as a mediator between the user, the model repository ROME, and the simulation framework CHEOPS. ModKit+ then provides specifications of the problem, the simulation setup, and correct references to the models which must be imported as files (cf. Subsect. 5.3.3). [Pg.490]

To complete the specification of the problem for 9, we must specify a particular velocity field u. In the case of Re <creeping-flow solutions of Chaps. 7 and 8, and it is again convenient to focus our attention on the case of a sphere in a uniform streaming flow, in which a first approximation to the velocity field is given by the Stokes solution, Eq. (7-158), from which we can calculate the velocity components by means of (7-102). [Pg.602]

This equation specifies an intensive property in the tank (specific or molar internal energy) at the point where it has admitted an amount of mass m. An additional property must be specified to fully define the state in the tank. This will depend on the specifics of the problem. For example, if the volume of the... [Pg.269]

No fluid can enter or exit through the wire frame at the top, and the film surface is pinned there. At the bottom, the film drains into the bath (or pool) in the cuvette, from which the film is drawn. The bath is otherwise inert, and it is assumed that the film shape tends to a static meniscus shape over the bath. This assumption will allow boundary conditions over the bath to be specified. The details of the mathematical specification of the problem appear elsewhere [57-60] in this section, the focus is on simplified models and comparing results from them with the experimental results discussed previously. [Pg.240]

The HlFi system allows the designer to move interactively from one level of specification to another, either in a top-down or in a bottom-up manner. The top-down direction typically starts out from a behavioral specification of the problem (described in chapter 2) and refines it to a structure of lower level behaviors according to a chosen algorithm. [Pg.73]

In the time optimal and energy optimal xenon overide problems, atoms of iodine and xenon make no direct contribution to the cost functional. Yet they have an indirect effect. If xenon is added at some time in the control period, the specification of the problem will not be met (i.e., the trajectory would not arrive at the target curve at the end of the control period as originally planned), and some correction will be necessary, for example, the extension of the control period at the final flux. Similarly, if iodine is added, there must be a perturbation in the control program, although the choice of correction may not be unique. [Pg.287]

Specification of the Problem. In the foUowing, the cardinalities 2, k are treated in detail. Hence appropriate edges in ovalene and drcumovalenes are to be counted, representing positions of naphthalene holes in the circular coronoids 2, k). [Pg.212]

For completing the specification of the problem we must state the initial age distribution of cells for each i. If there are no cells with scars originally, then the number densities must vanish identically for all z 1. The reader is referred to Hjortso and Bailey (1982, 1983) for a detailed treatment of yeast cell populations with population balance models. [Pg.37]


See other pages where Specification of the problem is mentioned: [Pg.272]    [Pg.28]    [Pg.35]    [Pg.43]    [Pg.54]    [Pg.77]    [Pg.86]    [Pg.153]    [Pg.160]    [Pg.168]    [Pg.175]    [Pg.43]    [Pg.238]    [Pg.8]    [Pg.20]    [Pg.8]    [Pg.140]    [Pg.253]    [Pg.219]    [Pg.323]    [Pg.343]    [Pg.257]    [Pg.20]    [Pg.573]    [Pg.152]    [Pg.73]    [Pg.478]    [Pg.558]   


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Problem specification

SPECIFIC PROBLEMS

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