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Area tabulations

You have been asked to determine the repeatability for a particular assay at the 100% target value. Prepare a standard solution containing the correct amount of analyte and run the solution six times in succession through the HPLC system, recording the values for peak area. Tabulate your results and calculate the RSD. Data from the accuracy section of the validation is also used to assess the precision of the assay by examining the percent of RSD obtained from all of the results. [Pg.166]

The coefficient k, expressed in J sec cm is the quantity of heat in joules, transmitted per second through a sample one centimeter in thickness and one square centimeter in area when the temperature difference between the two sides is one degree kelvin (or Celsius). The tabulated values are in microjoules. To convert to microcalories, divide values by 4.184. To convert to mW m divide values by 10. [Pg.507]

The gas permeability constant is the amount of gas expressed in cubic centimeters passed in 1 s through a 1-cm area of film when the pressure across a film thickness of 1 cm is 1 cmHg and the temperature is 25°C. All tabulated values are multiplied by 10 and are in units of seconds" (centimeters of Hg) k Other temperatures are indicated by exponents and are expressed in degrees Celsius. [Pg.1070]

In the discussion of Table 4.1, we acknowledged that there might be some uncertainty in the values of the quantities tabulated, but we sidestepped the origin of the uncertainty. In the next section we shall consider one of these areas the effect of crystal dimensions of the value of T j,. [Pg.211]

Particulate systems composed of identical particles are extremely rare. It is therefore usefiil to represent a polydispersion of particles as sets of successive size intervals, containing information on the number of particle, length, surface area, or mass. The entire size range, which can span up to several orders of magnitude, can be covered with a relatively small number of intervals. This data set is usually tabulated and transformed into a graphical representation. [Pg.126]

Basically, the tabled values represent area (proportions or probability) associated with a scaling variable designated by Z in Fig. 3-56. The normal cui ve is centered at 0, and for particular values of Z, designated as z, the tabulated numbers represent the corresponding area under the cui ve between 0 and z. For example, between 0 and 1 the area is. 3413. (Get this number from Table 3-4. The value of A includes the area on both sides of zero. Thus we want A/2. For z = 1, A = 0.6827, A/2 = 0.3413. For z = 2, A/2 = 0.4772.) The area between... [Pg.491]

For purposes of data correlation, model studies, and scale-up, it is useful to arrange variables into dimensionless groups. Table 6-7 lists many of the dimensionless groups commonly founa in fluid mechanics problems, along with their physical interpretations and areas of application. More extensive tabulations may oe found in Catchpole and Fulford (Ind. Eng. Chem., 58[3], 46-60 [1966]) and Fulford and Catchpole (Ind. Eng. Chem., 60[3], 71-78 [1968]). [Pg.674]

Performance data on some typical tray and compartment diyers are tabulated in Table 12-10. These indicate that an overall rate of evaporation of 0.0025 to 0.025 kg water/(s m") of tray area may be expected from tray and tray-truck diyers. The thermal efficiency of this type of diyer will vary from 20 to 50 percent, depending on the diying temperature used and the humidity of the exhaust air. In diying to very low moisture contents under temperature restrictions, the thermal efficiency may be in the order of 10 percent. The major operating cost for a tray diyer is the labor involved in loading and unloading the trays. About two labor-hours are required to load and unload a standard two-truck tray diyer. In addition, about one-third to one-fifth of a... [Pg.1192]

According to this method, it is not necessaiy to investigate the kinetics of the chemical reactions in detail, nor is it necessary to determine the solubihties or the diffusivities of the various reactants in their unreacted forms. To use the method for scaling up, it is necessaiy independently to obtain data on the values of the interfacial area per unit volume a and the physical mass-transfer coefficient /c for the commercial packed tower. Once these data have been measured and tabulated, they can be used directly for scahng up the experimental laboratory data for any new chemic ly reac ting system. [Pg.1366]

There are a number of different types of experimental laboratory units that could be used to develop design data for chemically reacting systems. Charpentier [ACS Symp. Sen, 72, 223-261 (1978)] has summarized the state of the art with respect to methods of scaUng up lab-oratoiy data and tabulated typical values of the mass-transfer coefficients, interfacial areas, and contact times to be found in various commercial gas absorbers as well as in currently available laboratoiy units. [Pg.1366]

Perhaps of more interest are also numerous reviews of specialized topical areas within shock-compression science as tabulated in Table 1.2. These specialized reviews contain much detailed information on the topics under con-... [Pg.9]

If T is normally distributed witli mean p and standard deviation a, then tlie random variable (T - p)/a is normally distributed with mean 0 and standard deviation 1. The term (T - p)/a is called a standard normal variable, and tlie graph of its pdf is called a "standard normal curve. Table 20.5.2 is a tabulation of areas under a standard normal cur e to tlie right of Zo of r normegative values of Zo. Probabilities about a standard normal variable Z can be detennined from tlie table. For example,... [Pg.584]

The collection and tabulation of data will provide an opportunity to become familiar with the company and will generate a good understanding of the operation of the plant. Much of the data will be needed to establish the models needed to size the various areas of the plant. For instance, hours worked should be analyzed to identify shift work, direct and indirect effort, and the normal and overtime activity. Outside contractors may be employed, and this contribution will need to be determined, sometimes by visiting the contractor s facilities. When expansions are being planned, it may be necessary to discuss the contributions that outside contractors make to the factory and assess the increase which they can accommodate. [Pg.69]

Table 1.29 tabulates most known examples of erosion corrosion problems occuring in aqueous systems. Historically, erosion corrosion first became a problem with the copper alloy (70%Cu 29%Zn l%Sn) condensers of naval shipsErosion corrosion of copper alloys has been an ongoing problem since then. The other major problem areas are (a) power plants where steels are exposed to water or water/steam mixtures in the temperature range 90°-280°C (b) the oil and gas industry where steels are exposed to various liquid, gas, and sometimes solids combinations containing carbon dioxide. [Pg.294]

The last comprehensive review of reactions between carbon-centered radicals appeared in 1973.142 Rate constants for radical-radical reactions in the liquid phase have been tabulated by Griller.14 The area has also been reviewed by Alfassi114 and Moad and Solomon.145 Radical-radical reactions arc, in general, very exothermic and activation barriers are extremely small even for highly resonance-stabilized radicals. As a consequence, reaction rate constants often approach the diffusion-controlled limit (typically -109 M 1 s"1). [Pg.36]

Repeating this procedure at the various temperature points selected, the heat-exchanger area may then be obtained as the area under a plot of Y.q vs. 1/6 A7 , or as A — Hq/UAT according to the following tabulation ... [Pg.481]

Research into cluster catalysis has been driven by both intrinsic interest and utilitarian potential. Catalysis involving "very mixed -metal clusters is of particular interest as many established heterogeneously catalyzed processes couple mid and late transition metals (e.g., hydrodesulfurization and petroleum reforming). Attempts to model catalytic transformations arc summarized in Section II.F.I., while the use of "very mixed -metal clusters as homogeneous and heterogeneous catalysis precursors are discussed in Sections I1.F.2. and I1.F.3., respectively. The general area of mixed-metal cluster catalysis has been summarized in excellent reviews by Braunstein and Rose while the tabulated results are intended to be comprehensive in scope, the discussion below focuses on the more recent results. [Pg.106]

Each scenario was modeled to determine the explosion overpressure at the three buildings under review. The resultant overpressures, and corresponding vulnerability estimates, for the most severe scenario in each process area are tabulated below. [Pg.44]

The catalyst consists of V205 supported on silica gel with K2S04 and other promoters also present. The physical property values tabulated below are typical of the low or intermediate surface area supports that one might expect to use in this application. DeMaria et al. (8) did not report data of these types for their catalyst. [Pg.559]

Data on the geographic distribution of surficial radium concentrations were acquired by the National Airborne Radiometric Reconnaissance (NARR) survey, part of the National Uranium Resource Evaluation (NURE) program conducted by the U.S. Department of Energy in the mid-1970s. The data were originally collected and tabulated by 1° by 2° quadrangle map area, and the data cover approximately 450 out of a total of 474 such quadrangles... [Pg.22]

NL-DFT analysis was then carried out to obtain more accurate information of the distribution of mesopores. It was shown that smaller mesopores with 2 to 12 nm diameter are formed only on calcined Co(20)/CyDTA/SiO2 catalyst, whereas mesopore diameter is distributed above 12 nm on other catalysts. In Table 6.2, cumulative pore volume (VJ and specific surface area (Sc) of mesopores are tabulated. Because of the presence of smaller mesopores, cumulative specific surface area of calcined Co(20)/CyDTA/SiO2 catalyst is larger than that of calcined Co(20)/SiO2 catalyst, whereas cumulative pore volume of the former is smaller. The formation... [Pg.104]

The tabulated volumes of nitrogen, cc at STP, were adsorbed on the surface of a 2.47 g sample at the pressures indicated at the atmospheric boiling point of nitrogen. Find the specific surface of the solid given that the area occupied by a nitrogen moleclule is 0.162(10-18) m2 and that Avogadro s number is 6.023(1023). [Pg.662]

Here the Ac is the channel cross-section flow area, and the factor, fRe, is a numerical constant computed and tabulated for various channel geometries. The characteristic dimension has been replaced by a hydraulic diameter defined as four times the flow area divided by the channel perimeter. [Pg.222]

Since the normal curve is symmetrical about u = 0, the area under the curve to the right of a given value u (i.e., the probability of occurrence, a, of a value greater than u i) is equal to the area to the left of — u i. It is therefore sufficient to tabulate only the values corresponding to positive values of u. For example, there is a probability of 0.05 than u will exceed 1.64, and hence that x will exceed pt + 1.64a. [Pg.277]


See other pages where Area tabulations is mentioned: [Pg.991]    [Pg.991]    [Pg.991]    [Pg.991]    [Pg.666]    [Pg.1855]    [Pg.36]    [Pg.483]    [Pg.1762]    [Pg.2319]    [Pg.62]    [Pg.504]    [Pg.12]    [Pg.45]    [Pg.445]    [Pg.153]    [Pg.4]    [Pg.185]    [Pg.26]    [Pg.305]    [Pg.216]    [Pg.171]    [Pg.178]    [Pg.62]    [Pg.153]    [Pg.514]   
See also in sourсe #XX -- [ Pg.7 , Pg.38 ]




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