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Severity approaches

To realize an automatic evaluation system, it would be desirable to also suppress geometrically caused signals as well, so that only the actual defect signals are obtained. Several approaches have already been made which are also to be implemented as part of a SQUID research project (SQUID = Super Conducting Quantum Interference Device). [Pg.310]

We have expressed P in tenns of Jacobi coordinates as this is the coordmate system in which the vibrations and translations are separable. The separation does not occur in hyperspherical coordinates except at p = oq, so it is necessary to interrelate coordinate systems to complete the calculations. There are several approaches for doing this. One way is to project the hyperspherical solution onto Jacobi s before perfonning the asymptotic analysis, i.e. [Pg.977]

Lamellar morphology variables in semicrystalline polymers can be estimated from the correlation and interface distribution fiinctions using a two-phase model. The analysis of a correlation function by the two-phase model has been demonstrated in detail before [30,11] The thicknesses of the two constituent phases (crystal and amorphous) can be extracted by several approaches described by Strobl and Schneider [32]. For example, one approach is based on the following relationship ... [Pg.1407]

There are several approaches to gain the required surface sensitivity with diffraction methods. We review several of these here, emphasizing the case of solid/vacuum interfaces some of these also apply to other interfaces. [Pg.1754]

To remedy this diflSculty, several approaches have been developed. In some metliods, the phase of the wavefunction is specified after hopping [178]. In other approaches, one expands the nuclear wavefunction in temis of a limited number of basis-set fiinctions and works out the quantum dynamical probability for jumping. For example, the quantum dynamical basis fiinctions could be a set of Gaussian wavepackets which move forward in time [147]. This approach is very powerfLil for short and intemiediate time processes, where the number of required Gaussians is not too large. [Pg.2320]

To obtain an effective algorithm for substructure searching the factorial degree of the brute force algorithm has to be drastically deaeased. In the next sections we discuss several approaches where combination leads to a much more effective and apphcable approach for substructure searching. In the process of searching the isomorphism between Gq and a substructure of Gx, the partial mappings Gq —> Gj can be used as well. In these cases, not all atoms from Gq are mapped and, for those which are not, the array value Mj is set to 0. [Pg.297]

Although Pd is cheaper than Rh and Pt, it is still expensive. In Pd(0)- or Pd(ll)-catalyzed reactions, particularly in commercial processes, repeated use of Pd catalysts is required. When the products are low-boiling, they can be separated from the catalyst by distillation. The Wacker process for the production of acetaldehyde is an example. For less volatile products, there are several approaches to the economical uses of Pd catalysts. As one method, an alkyldi-phenylphosphine 9, in which the alkyl group is a polyethylene chain, is prepared as shown. The Pd complex of this phosphine has low solubility in some organic solvents such as toluene at room temperature, and is soluble at higher temperature[28]. Pd(0)-catalyzed reactions such as an allylation reaction of nucleophiles using this complex as a catalyst proceed smoothly at higher temperatures. After the reaction, the Pd complex precipitates and is recovered when the reaction mixture is cooled. [Pg.5]

An analytical method is standardized by determining its sensitivity. There are several approaches to standardization, including the use of external standards, the method of standard addition. [Pg.130]

UV/Vis detectors are among the most popular. Because absorbance is directly proportional to path length, the capillary tubing s small diameter leads to signals that are smaller than those obtained in HPLC. Several approaches have been used to increase the path length, including a Z-shaped sample cell or multiple reflections (Figure 12.44). Detection limits are about 10 M. [Pg.604]

To apply these ideas to solution nonideality, we consider a theory developed by Flory and Krigbaum. This is only one of several approaches to the problem, but it is one which can be readily outlined in terms of material we have already developed. We shall only sketch the highlights of the Flory-Krigbaum theory, since the details are complicated and might actually obscure the principal ideas. [Pg.560]

WurtZ-Type Coupling of Dihalosilanes. Several approaches have been developed for the synthesis of polysdanes. However, the most commonly utilized method is based on the Wurtz-type alkah metal coupling of dichlorosilanes. Both homo- and copolymers can be prepared this way (eq. 10). [Pg.261]

Alkylphenols can be synthesized by several approaches, including alkylation of a phenol, hydroxylation of an alkylbenzene, dehydrogenation of an alkylcyclohexanol, or ring closure of an appropriately substituted acycHc compound. The choice of approach depends on the target alkylphenol, availabihty of the starting materials, and cost of processing. The procedures discussed herein encompass commercial methods, general methods, and a few specific examples of commercial interest. [Pg.58]

Crystallization from Solution. Crystallization techniques are related to the methods used to iaduce a driving force for soflds formation and to the medium from which crystals are obtained. Several approaches are defined ia the foUowiag discussion. [Pg.356]

There are several approaches to the preparation of multicomponent materials, and the method utilized depends largely on the nature of the conductor used. In the case of polyacetylene blends, in situ polymerization of acetylene into a polymeric matrix has been a successful technique. A film of the matrix polymer is initially swelled in a solution of a typical Ziegler-Natta type initiator and, after washing, the impregnated swollen matrix is exposed to acetylene gas. Polymerization occurs as acetylene diffuses into the membrane. The composite material is then oxidatively doped to form a conductor. Low density polyethylene (136,137) and polybutadiene (138) have both been used in this manner. [Pg.39]

Several approaches to unfused azetes have appeared, the most widely used being extrusion of small molecules from heterocyclic precursors. [Pg.282]

One potential difficulty with CF-EF is the electrodeposition of the particles at the electrode away from the filtration medium. This phenomenon, if allowed to persist, will result in performance decay of CF-EF with respect to maintenance of the electric field. Several approaches such as momentaiy reverses in polarity, protection of the electrode with a porous membrane or filter medium, and/or utilization of a high fluid shear rate can minimize electrodeposition. [Pg.2009]

Several approaches are available to eliminate this problem. If stresses cannot be sufficiently reduced, a metal possessing greater resistance to caustic SCC can be specified for replacement tubing. Alteration to the environment, such as eliminating alkalinity or increasing system pressure to prevent flashing (thereby minimizing the potential for concentration of caustic), would also prevent failure by this mechanism. [Pg.217]

Several approaches are available to alleviate or eliminate cavitation damage problems ... [Pg.279]

These and other considerations have led to attempts to produce materials which effectively cross-link on cooling to room temperature after processing but which on reheating appear to lose their cross-links. Several approaches to such fugitive cross-linking have been made in recent years of which the following have come to, or at least near to, commercial fruition ... [Pg.54]

Several approaches are used, either individually or collectively, to degrade polymers in this way. Of these the most important are ... [Pg.881]

The problem is one of constrained functional minimization, and has several approaches. [Pg.272]

Several approaches have been disclosed to make release coatings that can be printed with ink jet or laser jet printers (e.g., to make linerless labels). For example, Khatib and Langan [164] disclose a blend of two different acrylate functional silicones, one with a high level of acrylate functionality to provide the printability and one with a low level of acrylate functionality to provide easy PSA release. Lievre and Mirou [165] describe an aqueous blend of a crosslinkable silicone and poly(vinyl alcohol-vinyl acetate) resins while Shipston and Rice describe a blend of acrylic resin and a surfactant [166]. [Pg.565]

There are several approaches that can be used to tackle this problem and two of these will be considered now. [Pg.95]

Several approaches to the synthesis of nitronaphthyridines and their derivatives are reported. Very common ones are those in which the construction of the nitronaphthyridine system was achieved by using nitro synthons (see Section II,A) or by nitration of the naphthyridine ring, although a successful nitration requires the presence of electron-donating substituents (see Section II,B). Furthermore, the oxidation of the amino group in aminonaphthyridines... [Pg.286]

Several approaches to 4-amino-3-furazancarboxylic acid are known (Scheme 35). Thus, saponification of isocyanatofurazancarbonitrile with cone, sulfuric acid... [Pg.85]

Several approaches based on nitro-aldol for the synthesis of amino sugars have been reported Alumina-catalyzed reaction of methyl 3- nitropropanoate with O-benzyl-o-lactaldehyde gives the o-ribo-nitro-aldol fanti, and isomeri in 63% yield, which is converted into L-dannosamine fsee Secdon 3 3 Jager and coworkers have reported a short synthesis of L-acosamine based on the stereoselective nitro-aldol reaction of 2-O-benzyl-L-lactaldehyde with 3-nitropropanal dimethyl acetal as shovm in Scheme 3 10 The stereoselecdve nitro-aldol reacdon is carried ont by the silyl nitronate approach as discussed in Secdon 3 3... [Pg.50]


See other pages where Severity approaches is mentioned: [Pg.1770]    [Pg.106]    [Pg.109]    [Pg.118]    [Pg.134]    [Pg.11]    [Pg.297]    [Pg.36]    [Pg.65]    [Pg.172]    [Pg.444]    [Pg.449]    [Pg.412]    [Pg.231]    [Pg.329]    [Pg.1306]    [Pg.62]    [Pg.474]    [Pg.489]    [Pg.12]    [Pg.82]    [Pg.53]    [Pg.462]    [Pg.116]   


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