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As-determined basis

As-determined, basis analytical data obtained from the analysis sample of coal or coke after conditioning and preparation (ASTM D-2013 ASTM D-3180). [Pg.208]

Before suggesting an approach for predicting the minimum number of shells for an entire network, a more convenient method for determining the number of shells in a single unit must first be found. Adopting the design criterion given by Eq. (7.13) as the basis, then any need for trial and error can be eliminated, since an explicit... [Pg.225]

Obviously, the BO or the adiabatic states only serve as a basis, albeit a useful basis if they are determined accurately, for such evolving states, and one may ask whether another, less costly, basis could be Just as useful. The electron nuclear dynamics (END) theory [1-4] treats the simultaneous dynamics of electrons and nuclei and may be characterized as a time-dependent, fully nonadiabatic approach to direct dynamics. The END equations that approximate the time-dependent Schrddinger equation are derived by employing the time-dependent variational principle (TDVP). [Pg.221]

For a particular process, this expression should be multiplied with the probability for that process as determined by projection of the END evolved state v /(t) for the system on the appropriate final state v /y described within the same basis set and at the same level of approximation as the evolved state, that is, the amplitude (< /y t /(f)) at a sufficiently large time f. [Pg.236]

The data in Table 7.6 list the mole fraction of methyl acrylate in the feedstock and in the copolymer for the methyl acrylate (Mi)-vinyl chloride (M2) system. Use Eq. (7.54) as the basis for the graphical determination of the reactivity ratios which describe this system. [Pg.459]

Quantitative Analysis of All llithium Initiator Solutions. Solutions of alkyUithium compounds frequentiy show turbidity associated with the formation of lithium alkoxides by oxidation reactions or lithium hydroxide by reaction with moisture. Although these species contribute to the total basicity of the solution as determined by simple acid titration, they do not react with allyhc and henzylic chlorides or ethylene dibromide rapidly in ether solvents. This difference is the basis for the double titration method of determining the amount of active carbon-bound lithium reagent in a given sample (55,56). Thus the amount of carbon-bound lithium is calculated from the difference between the total amount of base determined by acid titration and the amount of base remaining after the solution reacts with either benzyl chloride, allyl chloride, or ethylene dibromide. [Pg.239]

Protein Content. The protein content of milk can be determined using a variety of methods including gasometric, Kjeldahl, titration, colorimetric, and optical procedures (see Proteins). Because most of the techniques are too cumbersome for routine use in a dairy plant, payment for milk has seldom been made on the basis of its protein content. Dye-binding tests have been appHed to milk for determination of its protein content these are relatively simple to perform and can be carried out in dairy plant laboratories. More emphasis will be given to assessing the nutritional value of milk, and the dependence on fat content as a basis for payment will most likely change. [Pg.364]

Defects in the LDL receptor have been particularly well explored as a basis of the disease familial hypercholesterolemia (93,111). A number of defects that collectively impair LDL receptor trafficking, binding, or deUvery underHe this disease where LDL and semm cholesterol rise to levels that mediate early cardiovascular mortaUty. Studies of the population distribution of this defect can determine the source of the original mutation. Thus, in Quebec, about 60% of the individuals suffering from familial hypercholesterolemia have a particular 10-kdobase deletion mutation in the LDL gene (112). This may have arisen from an original founder of the French Canadian settiement in the seventeenth century. [Pg.283]

Critical Micelle Concentration. The rate at which the properties of surfactant solutions vary with concentration changes at the concentration where micelle formation starts. Surface and interfacial tension, equivalent conductance (50), dye solubilization (51), iodine solubilization (52), and refractive index (53) are properties commonly used as the basis for methods of CMC determination. [Pg.238]

As Olah et al. have reported (81JOC2706), iV-nltropyrazole in the presence of Lewis or Brpnsted acid catalysts is an effective nitrating agent for aromatic substrates. The greater lability of the N—NO2 bond in iV-nltropyrazole compared with aliphatic nltramines was discussed on the basis of its molecular structure as determined by X-ray crystallography. [Pg.270]

To use Eq. (18--50) one must know the pattern of the filtration process, i.e., the variation of the flow rate and pressure with time. Generally the pumping mechanism determines the filtration flow characteristics and serves as a basis for the following three categories [Tiller and Crump, Chem. Eng. Prog., 73(10), 65 (1977)] ... [Pg.1704]

Any difference in physical properties of the individual solids can be used as the basis for separation. Differences in density size, shape, color, and electrical and magnetic properties are used in successful commercial separation processes. An important factor in determining the techniques that can be prac tically applied is the particle-size range of the mixture. A convenient guide to the application of different solid-solid separation techniques in relation to the particle-size range is presented in Fig. 19-1, which is a modification of an original illustration by Roberts et al. [Pg.1756]

The complexes on surface of chelate-functionalized silica often include ligands available in solution in the coordination sphere. Use of a chromophore reagent as a ligand leads to the formation of colored mixed ligand complexes (MLC). The phenomena can be used as a basis for developing test-systems for visual determination of microquantities of inorganic cations in water. [Pg.43]

Reduced molibdophosphoric HPA was found to be well recovered by silica modified with tetradecyl ammonium nitrate. It was assumed as a basis of phosphoms determination in the range of 0.5-5 pmole using solid-phase spectrometry. [Pg.60]

BBT solution on unmodified sorbents of different nature was studied. Silica gel Merck 60 (SG) was chosen for further investigations. BBT immobilization on SG was realized by adsoi ption from chloroform-hexane solution (1 10) in batch mode. The isotherm of BBT adsoi ption can be referred to H3-type. Interaction of Co(II), Cu(II), Cd(II), Ni(II), Zn(II) ions with immobilized BBT has been studied in batch mode as a function of pH of solution, time of phase contact and concentration of metals in solution. In the presence of sodium citrate absorbance (at X = 620 nm) of immobilized BBT grows with the increase of Cd(II) concentration in solution. No interference was observed from Zn(II), Pb(II), Cu(II), Ni(II), Co(II) and macrocomponents of natural waters. This was assumed as a basis of soi ption-spectroscopic and visual test determination of Cd(II). Heavy metals eluted from BBT-SG easily and quantitatively with a small volume of HNO -ethanol mixture. This became a basis of soi ption-atomic-absoi ption determination of the total concentration of heavy metals in natural objects. [Pg.292]

Similarly, contaminant concentrations in rivers or streams can be roughly assessed based on rate of contaminant introduction and dilution volumes. Estuary or impoundment concentration regimes are highly dependent on the transport mechanisms enumerated. Contaminants may be localized and remain concentrated or may disperse rapidly and become diluted to insignificant levels. The conservative approach is to conduct a more in-depth assessment and use model results or survey data as a basis for determining contaminant concentration levels. [Pg.235]

The vibration characteristics, determined by use of the instrumentation, will serve as the basis for acceptance or rejection of the machine. API standards generally require that the equipment be operated at speed increments of approximately 10% from zero to the maximum continuous speed and run at the maximum continuous speed until bearings, lube-oil temperatures, and shaft vibrations have stabilized. Next, the speed should be increased to trip speed and the equipment run for a minimum of 15 minutes. Finally, the speed should be reduced to the maximum continuous speed and the equipment should be run for four hours. API does not require that the four hours be uninterrupted however, it is generally interpreted that way. The interpretation is one of the many test criteria to be discussed. It would seem that a break in the test at the midpoint is not the same as having it cut short five minutes from the end because the vendor s boiler took an upset that was not related to the compressor test. The ibration during the shop test is normally specified as the API limit of 1.0 mils peak to peak, or the value from Equation 10.1, unfiltcred. whichever is lower. [Pg.410]

Here, we shall examine a series of processes from the viewpoint of their kinetics and develop model reactions for the appropriate rate equations. The equations are used to andve at an expression that relates measurable parameters of the reactions to constants and to concentration terms. The rate constant or other parameters can then be determined by graphical or numerical solutions from this relationship. If the kinetics of a process are found to fit closely with the model equation that is derived, then the model can be used as a basis for the description of the process. Kinetics is concerned about the quantities of the reactants and the products and their rates of change. Since reactants disappear in reactions, their rate expressions are given a... [Pg.109]

The equilibrium constant can be determined at any temperature from standard state information on reactants and product. Considering the synthesis of NH3, the equilibrium conversion can be determined for a stoichiometric feed of Hj and Nj, at the total pressure. These conversions are determined by the number of moles of each species against conversion X by taking as a basis, 1 mole of N2. [Pg.481]

Shock-compressed solids and shock-compression processes have been described in this book from a perspective of solid state physics and solid state chemistry. This viewpoint has been developed independently from the traditional emphasis on mechanical deformation as determined from measurements of shock and particle velocities, or from time-resolved wave profiles. The physical and chemical studies show that the mechanical descriptions provide an overly restrictive basis for identifying and quantifying shock processes in solids. These equations of state or strength investigations are certainly necessary to the description of shock-compressed matter, and are of great value, but they are not sufficient to develop a fundamental understanding of the processes. [Pg.197]

An analysis of this type is appropriate during the preliminary design stage when process alternatives may have to be screened economically, or when it is necessary to determine a feasible design as the basis for equipment trials and/or final designs. [Pg.271]


See other pages where As-determined basis is mentioned: [Pg.195]    [Pg.402]    [Pg.409]    [Pg.411]    [Pg.412]    [Pg.414]    [Pg.195]    [Pg.402]    [Pg.409]    [Pg.411]    [Pg.412]    [Pg.414]    [Pg.96]    [Pg.131]    [Pg.140]    [Pg.298]    [Pg.258]    [Pg.83]    [Pg.121]    [Pg.693]    [Pg.36]    [Pg.276]    [Pg.424]    [Pg.477]    [Pg.848]    [Pg.2170]    [Pg.354]    [Pg.443]    [Pg.555]    [Pg.39]    [Pg.43]    [Pg.139]    [Pg.117]    [Pg.371]   
See also in sourсe #XX -- [ Pg.9 , Pg.42 ]




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A) determinations

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