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Utility number

Number of total components to utilize Number of atoms in a specific component Number of ring atoms in a specific component Molecular weight... [Pg.207]

In evaluation of the parameters Aj and Bj, Timm and Ra-chow ( ) utilized number and weight average molecular weights coupled with the observed, normalized chromatogram for that standard. Specifically,... [Pg.115]

What are the health-economic consequences of a disease, in terms of healthcare utilization (number and duration of hospitalizations, frequency of use of healthcare resources, direct and indirect cost of treatment, lost productivity and activity, the overall burden of a disease on the environment and society) ... [Pg.146]

Table 1 Utilizing number of individuals of Medicaid services in FY 1998... Table 1 Utilizing number of individuals of Medicaid services in FY 1998...
In this manuscript, bracketed numbers (e.g., ([4+2]) are used to describe the number of atoms in each component of a cycloaddition reaction. Thus this notation is differentiated from electronic designations which, by convention, utilize numbers with subscripts indicating orbital type (e.g., 4p+2p). [Pg.42]

Track key metrics (e.g. agent utilization, number of processing errors, etc.). [Pg.328]

The PDEF file from your floorplanner specifies a max utilization number for each of the clusters. [Pg.194]

Recall from Chapter 2 the definition of atom economy, the ratio of the mass of the species in the desired product relative to the mass of all of the reactants. In all of these reactions the atoms present in the reactants are also present in the products. In this case it is implied that these reactions are 100% atom economical. Remember from Chapter 2 that atom economy is a mass utilization number only it does not take into account the energy usage, the toxicity of the products, or whether the feedstocks are derived from renewable materials. [Pg.116]

Another variable that needs to be set for distillation is refiux ratio. For a stand-alone distillation column, there is a capital-energy tradeoff, as illustrated in Fig. 3.7. As the refiux ratio is increased from its minimum, the capital cost decreases initially as the number of plates reduces from infinity, but the utility costs increase as more reboiling and condensation are required (see Fig. 3.7). If the capital... [Pg.77]

S = number of streams including utilities (points in graph theory)... [Pg.214]

Equation (7.2) put in words states that the minimum number of units required is one less than the number of streams (including utility streams). [Pg.215]

Rgura 7.2 To target the number of units for pinched problems, the streams above and below the pinch must be counted separately, with the appropriate utilities included. [Pg.216]

Increasing the chosen value of process energy consumption also increases all temperature differences available for heat recovery and hence decreases the necessary heat exchanger surface area (see Fig. 6.6). The network area can be distributed over the targeted number of units or shells to obtain a capital cost using Eq. (7.21). This capital cost can be annualized as detailed in App. A. The annualized capital cost can be traded off against the annual utility cost as shown in Fig. 6.6. The total cost shows a minimum at the optimal energy consumption. [Pg.233]

Consider again the simple process shown in Fig. 4.4d in which FEED is reacted to PRODUCT. If the process usbs a distillation column as separator, there is a tradeofi" between refiux ratio and the number of plates if the feed and products to the distillation column are fixed, as discussed in Chap. 3 (Fig. 3.7). This, of course, assumes that the reboiler and/or condenser are not heat integrated. If the reboiler and/or condenser are heat integrated, the, tradeoff is quite different from that shown in Fig. 3.7, but we shall return to this point later in Chap. 14. The important thing to note for now is that if the reboiler and condenser are using external utilities, then the tradeoff between reflux ratio and the number of plates does not affect other operations in the flowsheet. It is a local tradeoff. [Pg.239]

Before any matches are placed, the target indicates that the number of units needed is equal to the number of streams (including utility streams) minus one. The tick-off heuristic satisfied the heat duty on one stream every time one of the units was used. The stream that has been ticked off is no longer part of the remaining design problem. The tick-off heuristic ensures that having placed a unit (and used up one of our available units), a stream is removed from the problem. Thus Eq. (7.2) is satisfied if eveiy match satisfies the heat duty on a stream or a utility. [Pg.370]

Example 16.1 The process stream data for a heat recovery network problem are given in Table 16.1. A problem table analysis on these data reveals that the minimum hot utility requirement for the process is 15 MW and the minimum cold utility requirement is 26 MW for a minimum allowable temperature diflFerence of 20°C. The analysis also reveals that the pinch is located at a temperature of 120°C for hot streams and 100°C for cold streams. Design a heat exchanger network for maximum energy recovery in the minimum number of units. [Pg.371]

The pinch design method developed earlier followed several rules and guidelines to allow design for minimum utility (or maximum energy recovery) in the minimum number of units. Occasionally, it appears not to be possible to create the appropriate matches because one or other of the design criteria cannot be satisfied. [Pg.372]

The network can now be designed using the pinch design method.The philosophy of the pinch design method is to start at the pinch and move away. At the pinch, the rules for the CP inequality and the number of streams must be obeyed. Above the utility pinch and below the process pinch in Fig. 16.17, there is no problem in applying this philosophy. However, between the two pinches, there is a problem, since designing away from both pinches could lead to a clash where both meet. [Pg.381]

The composite curves (including utilities) are divided into enthalpy intervals. The minimum (fractional) number of shells for the temperatures of each interval k is evaluated using Eqs. (D.7) to (D.9). [Pg.441]

The two numbers each have their own utility which explains why both are taken into account when setting specifications. Nevertheless, in the context of refining today, it is the minimum MON that is the most difficult constraint for the refiner. For example, to obtain an 85 MON for Eurosuper it often happens that the RON is greater than 95 in actual practice it is 96 or even 97. Likewise, Superplus can represent, for an 88 MON, an RON of 99 or 100. [Pg.199]

The gradual reduction and ultimate elimination of lead has seen considerable effort by the refiner to maintain the octane numbers at satisfactory levels. In Europe, the conventional unleaded motor fuel, Eurosuper, should have a minimum RON of 95 and a minimum MON of 85. These values were set in 1983 as the result of a technical-economic study called RUFIT (Rational Utilization of Fuels in Private Transport). A compromise was then possible between refining energy expenses and vehicle fuel consumption (Anon., 1983). [Pg.210]

The additives for improving the cetane number, called pro-cetane, are particularly unstable oxidants, the decomposition of which generates free radicals and favors auto-ignition. Two families of organic compounds have been tested the peroxides and the nitrates. The latter are practically the only ones being used, because of a better compromise between cost-effectiveness and ease of utilization. The most common are the alkyl nitrates, more specifically the 2-ethyl-hexyl nitrate. Figure 5.12 gives an example of the... [Pg.221]

To give some structure to the process design it is common to present information and ideas in the form of process flow schemes (PFS). These can take a number of forms and be prepared in various levels of detail. Atypical approach is to divide the process into a hierarchy differentiating the main process from both utility and safety processes. [Pg.239]

The 3D inspection system has a number of measuring and report utilities that enables the user to easily find, analyse and report possible indications in the test object. As an example, a moveable 2D projection view plane can be moved along e.g, the welding geometry dynamically updating the content of the 2D projection view window. Indications can be measured using any referenee co-ordinate system and the results and screen dumps can automatically be dumped in report files suited for later import into a word processing application. [Pg.872]

A term that is nearly synonymous with complex numbers or functions is their phase. The rising preoccupation with the wave function phase in the last few decades is beyond doubt, to the extent that the importance of phases has of late become comparable to that of the moduli. (We use Dirac s terminology [7], which writes a wave function by a set of coefficients, the amplitudes, each expressible in terms of its absolute value, its modulus, and its phase. ) There is a related growth of literatm e on interference effects, associated with Aharonov-Bohm and Berry phases [8-14], In parallel, one has witnessed in recent years a trend to construct selectively and to manipulate wave functions. The necessary techifiques to achieve these are also anchored in the phases of the wave function components. This bend is manifest in such diverse areas as coherent or squeezed states [15,16], elecbon bansport in mesoscopic systems [17], sculpting of Rydberg-atom wavepackets [18,19], repeated and nondemolition quantum measurements [20], wavepacket collapse [21], and quantum computations [22,23], Experimentally, the determination of phases frequently utilizes measurement of Ramsey fringes [24] or similar" methods [25]. [Pg.96]

Phase interference in optical or material systems can be utilized to achieve a type of quantum measmement, known as nondemolition measurements ([41], Chapter 19). The general objective is to make a measurement that does not change some property of the system at the expense of some other property(s) that is (are) changed. In optics, it is the phase that may act as a probe for determining the intensity (or photon number). The phase can change in the comse of the measurement, while the photon number does not [126]. [Pg.103]

Basically, two different methods arc commonly used for representing a chemical struchiive in 3D space. Both methods utilize different coordinate systems to describe the spatial arrangement of the atoms of a molecule under con.sidcration. The most common way is to choose a Cartesian coordinate system, i.e., to code the X-, y-, and z-coordinates of each atom, usually as floating point numbers, For each atom the Cartesian coordinates can be listed in a single row. giving consecutively the X-, )> , and z-valnc.s. Figure 2-90 illustrates this method for methane. [Pg.92]

A number of other software packages are available to predict NMR spectra. The use of large NMR spectral databases is the most popular approach it utilizes assigned chemical structures. In an advanced approach, parameters such as solvent information can be used to refine the accuracy of the prediction. A typical application works with tables of experimental chemical shifts from experimental NMR spectra. Each shift value is assigned to a specific structural fragment. The query structure is dissected into fragments that are compared with the fragments in the database. For each coincidence, the experimental chemical shift from the database is used to compose the final set of chemical shifts for the... [Pg.519]

In the following decades, chemists tried to utilize more and more the knowledge on reactions which had already been gained. A number of landmark syntheses represent the change to modern chemistry, such as the synthesis of the estrogenic steroid equilenin (W. Bachmann, 1939), of pyridoxine (K. Folkers, 1939), and of quinine (R.B. Woodward, W. von E. Doering, 1944) [23]. [Pg.568]

Note that in equation system (2.64) the coefficients matrix is symmetric, sparse (i.e. a significant number of its members are zero) and banded. The symmetry of the coefficients matrix in the global finite element equations is not guaranteed for all applications (in particular, in most fluid flow problems this matrix will not be symmetric). However, the finite element method always yields sparse and banded sets of equations. This property should be utilized to minimize computing costs in complex problems. [Pg.48]

YAcHMOP stands for yet another extended Hiickel molecular orbital package. The package has two main executables and a number of associated utilities. The bind program does molecular and crystal band structure extended Hiickel calculations. The viewkel program is used for displaying results. We tested Version 3.0 of bind and Version 2.0 of viewkel. [Pg.343]

MacroModel (we tested Version 6.5) is a powerful molecular mechanics program. The program can be run from either its graphic interface or an ASCII command file. The command file structure allows very complex simulations to be performed. The XCluster utility permits the analysis and filtering of a large number of structures, such as Monte Carlo or dynamics trajectories. The documentation is very thorough. [Pg.344]

I undertook the present task to give a birds-eye view of the broad field of palladium in organic synthesis. 1 have tried to accomplish this ttisk by citing many references these were selected from a much larger number which I have collected over the years. I tried to be as comprehensive as possible by selecting those references which reported original ideas and new reactions, or evident synthetic utility. Synthetic utility is clearly biased towards catalytic rather than stoichiometric reactions and this emphasis is apparent in the selection of the... [Pg.559]

Equation 19 utilizes the Y-residuals, 1) — Y, where 1) are the points on the calculated best-fit line or the fitted 1) values. The appropriate number of degrees of freedom is A — 2 the minus 2 arises from the fact that linear calibration lines are derived from both a slope and an intercept which leads to a loss of two degrees of freedom. [Pg.209]


See other pages where Utility number is mentioned: [Pg.546]    [Pg.546]    [Pg.2]    [Pg.87]    [Pg.188]    [Pg.364]    [Pg.1671]    [Pg.2338]    [Pg.2355]    [Pg.2390]    [Pg.2651]    [Pg.2977]    [Pg.476]    [Pg.683]    [Pg.125]    [Pg.327]    [Pg.167]   
See also in sourсe #XX -- [ Pg.4 ]




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