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The Jones method

The ideal response value is represented by r, represents the mean response at a particular value of the product design factor (represented by the index x) calculated over the region of interest of the environmental factors (R ), so [Pg.167]

Jones uses an integrated squared error loss value [L(x) as the performance criterion  [Pg.168]

But this L(x) value has in fact the same problem as an S/N ratio, it contains two experimental goals with a fixed relation between them. This problem is solved by separating L(x) into two distinct criteria, which are  [Pg.168]

To control the relation between M(x) and V(x) in L(x), which is in equation (17) still completely dependent on t, a weighing factor /L is introduced, which results in  [Pg.168]

Another important advantage of using a response surface methodology based method, like Jones method, is that a mathematical model is used to describe the response as a function of the product design and environmental variables. Using this model, interpolations of the product [Pg.168]


Upon completion of data collection, estimation of values for the remaining compounds was performed. The estimates are primarily based on the methods of Shebeko (16) and Jones (2). The Jones method (regression of the stoichiometric concentrations for volume % fuel in fuel plus air) is shown below ... [Pg.54]

The two most common methods used to correct resolved peak profiles for the broadening imposed by the finite width of the X-ray beam in the diffractometer, are due to Jones (15) and Stokes (16). Both are essentially unfolding or deconvolution methods, but the Jones method defines specific functions for both the uncorrected and the instrumental broadening profile. If the uncorrected profile is Gaussian, then... [Pg.171]

The methods in general use for separating the size and distortion broadening components of the resolved and corrected peak profiles can be separated into two groups, non-transform and transform methods. The non-transfona methods are essentially similar to the Jones method, being approximations to a convolution. The transform method discussed here makes use of the Fourier coefficients found after the Stokes correction. [Pg.172]

This mixture was saponified with methanolic potassium hydroxide to give the two epimers of 267 in quantitative yield. By enol acetylation, 267 was converted to 268 which in turn was oxidized by osmium tetroxide and periodate to the noraldehydes 269. The mixture 269 was converted to 270 via oxidation, esterification, and mild alkaline hydrolysis. The hydroxyesters 270 were oxidized by the Jones method to afford the single crystalline diketoester 271. Ketalization of 271 yielded the ketal 272 in quantitative... [Pg.172]

The Jones method is rapid and the yields high. The main limitation is the low solvent power of acetone. However, the method was used successfully by Eisen-braun for oxidation of cyclooctanol to cyclooctanone on a fairly large scale. [Pg.805]

Other oxidation procedures were used, e.g., pyrldinium chlorochromate (Corey s reagent), and dipyridine Cr(VI) oxide (Collins reagent), but did not produce yields comparable to the Jones method. [Pg.178]

The basic principle underlying the Jones method is that any elliptic vibration can be represented by the column vector... [Pg.214]

Two simulation methods—Monte Carlo and molecular dynamics—allow calculation of the density profile and pressure difference of Eq. III-44 across the vapor-liquid interface [64, 65]. In the former method, the initial system consists of N molecules in assumed positions. An intermolecule potential function is chosen, such as the Lennard-Jones potential, and the positions are randomly varied until the energy of the system is at a minimum. The resulting configuration is taken to be the equilibrium one. In the molecular dynamics approach, the N molecules are given initial positions and velocities and the equations of motion are solved to follow the ensuing collisions until the set shows constant time-average thermodynamic properties. Both methods are computer intensive yet widely used. [Pg.63]

There are various, essentially equivalent, versions of the Verlet algoritlnn, including the origmal method employed by Verlet [13, 44] in his investigations of die properties of the Lennard-Jones fluid, and a leapfrog fonn [45]. Here we concentrate on the velocity Verlet algoritlnn [46], which may be written... [Pg.2250]

Finally, the parametrization of the van der Waals part of the QM-MM interaction must be considered. This applies to all QM-MM implementations irrespective of the quantum method being employed. From Eq. (9) it can be seen that each quantum atom needs to have two Lennard-Jones parameters associated with it in order to have a van der Walls interaction with classical atoms. Generally, there are two approaches to this problem. The first is to derive a set of parameters, e, and G, for each common atom type and then to use this standard set for any study that requires a QM-MM study. This is the most common aproach, and the derived Lennard-Jones parameters for the quantum atoms are simply the parameters found in the MM force field for the analogous atom types. For example, a study that employed a QM-MM method implemented in the program CHARMM [48] would use the appropriate Lennard-Jones parameters of the CHARMM force field [52] for the atoms in the quantum region. [Pg.225]

Figure 18.12 The electron-density map is interpreted by fitting into it pieces of a polypeptide chain with known stereochemistry such as peptide groups and phenyl rings. The electron density (blue) is displayed on a graphics screen in combination with a part of the polypeptide chain (red) in an arbitrary orientation (a). The units of the polypeptide chain can then be rotated and translated relative to the electron density until a good fit is obtained (b). Notice that individual atoms are not resolved in such electron densities, there are instead lumps of density corresponding to groups of atoms. [Adapted from A. Jones Methods Enzym. (eds. H.W. Wyckoff, C.H. Hirs, and S.N. Timasheff) 115B 162, New York Academic Press, 1985.]... Figure 18.12 The electron-density map is interpreted by fitting into it pieces of a polypeptide chain with known stereochemistry such as peptide groups and phenyl rings. The electron density (blue) is displayed on a graphics screen in combination with a part of the polypeptide chain (red) in an arbitrary orientation (a). The units of the polypeptide chain can then be rotated and translated relative to the electron density until a good fit is obtained (b). Notice that individual atoms are not resolved in such electron densities, there are instead lumps of density corresponding to groups of atoms. [Adapted from A. Jones Methods Enzym. (eds. H.W. Wyckoff, C.H. Hirs, and S.N. Timasheff) 115B 162, New York Academic Press, 1985.]...
Although as already stated the use of metal amalgams, and in particular use of the Jones reductor or of the related silver reductor, is the best method of reducing solutions in preparation for titration with an oxidant, it may happen that for occasional use there is no Jones reductor available, and a simpler procedure will commend itself. In practical terms, the need is most likely to arise in connection with the determination of iron, for which the reduction of iron(III) to iron(II) may be necessary. [Pg.415]

Bockris and Parry-Jones, friction method for the potential of zero charge, 40 Bockris and Sen, theory of the friction method for determining the potential of zero charge, 40 Bubbles... [Pg.627]

Analysis of methyl parathion in sediments, soils, foods, and plant and animal tissues poses problems with extraction from the sample matrix, cleanup of samples, and selective detection. Sediments and soils have been analyzed primarily by GC/ECD or GC/FPD. Food, plant, and animal tissues have been analyzed primarily by GC/thermionic detector or GC/FPD, the recommended methods of the Association of Official Analytical Chemists (AOAC). Various extraction and cleanup methods (AOAC 1984 Belisle and Swineford 1988 Capriel et al. 1986 Kadoum 1968) and separation and detection techniques (Alak and Vo-Dinh 1987 Betowski and Jones 1988 Clark et al. 1985 Gillespie and Walters 1986 Koen and Huber 1970 Stan 1989 Stan and Mrowetz 1983 Udaya and Nanda 1981) have been used in an attempt to simplify sample preparation and improve sensitivity, reliability, and selectivity. A detection limit in the low-ppb range and recoveries of 100% were achieved in soil and plant and animal tissue by Kadoum (1968). GC/ECD analysis following extraction, cleanup, and partitioning with a hexane-acetonitrile system was used. [Pg.181]

The author thanks the following scientists at DuPont Crop Protection for developing the methods summarized in this chapter Jennifer S. Amoo and William Jones for the watery/dry crop method M. Elena Cabusas, Brock Peterson and Dennis Walker for the alternative watery/dry crop method James J. Stry, Michael Gagnon and Sidney Hill for the soil method and the oily crop method and Lei Jin and Timothy Devine for the water method. [Pg.410]

Several authors observed CL emission based on reduction reactions. Lu et al. [59] developed a method by applying a Jones reductor for producing unstable reductants. A column (100 X 3 mm i.d.) filled with Zn-Hg particles was inserted into the flow stream of a flow injection system. CL was measured using a homemade CL analyzer. Although the Jones reductor was more effective for the species studied in 0.5-5 mol/L H2S04 solution, the authors found that a lower acid concentration improved the CL emission. Hie optimal pH was 6.5 for V(II), 2.5 for Mo(III), 3.5 for U(III), 3.0 for W(III), 3.0 for Cr(II), 2.5 for Ti(III), and 2.5 for Fe(II). The methods allowed determination of the above-mentioned species at pg/mL to ng/mL levels. It was assumed that the CL reactions were related to the production of superoxide radicals by dissolved oxygen in the solutions. The proposed methods could be successfully applied to the determination of V [60], Mo [61], and U [62] in water or steel samples. [Pg.128]

The conventional method for determining the cell constant of a conductance cell involves the use of solutions of known specific resistance. The a-queous KC1 solutions of Jones and Bradshaw 32) are the currently accepted standards. These workers carefully measured three solutions of given weight concentrations corresponding to molarities of about 1,0.1 and 0.01. There are two disadvantages to this approach. First, a solution of an exactly specified concentration must be prepared. Second, it does not permit measurement of the cell constant over a range of concentrations in order to test for stray current leakages which would cause systematic variations in the calculated constant. [Pg.9]

Unfortunately, Maxwell s equations can be solved analytically for only a few simple canonical resonator structures, such as spheres (Stratton, 1997) and infinitely long cylinders of circular cross-sections (Jones, 1964). For arbitrary-shape microresonators, numerical solution is required, even in the 2-D formulation. Most 2-D methods and algorithms for the simulation of microresonator properties rely on the Effective Index (El) method to account for the planar microresonator finite thickness (Chin, 1994). The El method enables reducing the original 3-D problem to a pair of 2-D problems for transverse-electric and transverse-magnetic polarized modes and perform numerical calculations in the plane of the resonator. Here, the effective... [Pg.58]


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Jones’ method

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