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Recent Approachs

As an indication of the types of infonnation gleaned from all-electron methods, we focus on one recent approach, the FLAPW method. It has been used to detennine the band stmcture and optical properties over a wide energy range for a variety of crystal stmctures and chemical compositions ranging from elementary metals [ ] to complex oxides [M], layered dichalcogenides [, and nanoporous semiconductors The k p fonnulation has also enabled calculation of the complex band stmcture of the A1 (100) surface... [Pg.2214]

The most recent approach to reductive nanofabrication that can indeed constmct nanoscale stmctures and devices uses microscopic tools (local probes) that can build the stmctures atom by atom, or molecule by molecule. Optical methods using laser cooling (optical molasses) are also being developed to manipulate nanoscale stmctures. [Pg.203]

An attempt has been made to define a single critical value, like for brittle fracture, from these curves (5). However, the amount of crack growth which is used to define this critical value is inevitably rather arbitrary. A more recent approach (6) is to fit a power law curve of the form... [Pg.546]

Significant recent approaches to chemical reactor network synthesis can be classified into two categories, viz. superstructure optimization and network targeting. In the former, a superstructure is postulated and then an optimal sub-network within it is identified to maximize performance index (Kokossis and Floudas, 1990). [Pg.281]

The steric constant Es and related quantities do not constitute the only approach to the study of steric effects on reactivity. Steric strain energy calculations and topological indices are more recent approaches. Qualitative concepts have been... [Pg.343]

One of the more recent approaches for designing xc functionals is based on inverting eq. (6.7). An accurate electron density may be calculated by advanced wave... [Pg.181]

Comparatively little space will therefore be devoted to some rather recent approaches, such as the plasma model of Bohm and Pines, the two-body interaction method developed by Brueckner in connection with nuclear theory, Daudel s loge theory, and the method of variation of the second-order density matrix. This does not mean that these methods would be less powerful or less impor-... [Pg.211]

We then turn to a more recent approach to the determination of i by Point [51, 52] in Sect. 3.7 explaining how it differs from that of Lauritzen and Hoffman (LH). Section 3.8 covers other proposed nucleation models and we conclude with an overview of nucleation theories and their successes and most notable shortcomings. [Pg.236]

Surprisingly, after this very first example, there was a 20 year delay in the literature in the appearance of the second report on siloxane macromonomers. However, during this period there have been numerous studies and developments in the vinyl and diene based macromonomers91 -94). The recent approach to the synthesis of siloxane macromonomers involves the lithiumtrimethylsilanolate initiated anionic polymerization of hexamethyltrisiloxane in THF 95,123). The living chain ends were then terminated by using styrene or methacrylate functional chlorosilanes as shown in Reaction Scheme X. [Pg.23]

A recent approach was based on the DMAc/LiCl and N-methyl-2-pyrrohdone/IiCl solvent systems [252,253] that enabled better dry tensile strengths although they did not provide adequate wet tenacities, due to poor crystallinity and poor consohdation of the fibre. A further problem was the... [Pg.185]

NLP systems are being developed to address the increasingly challenging problem of data mining for systems level content from the published literature, that is, integrating across the global expert database of biomedical research [71]. One recent approach to this problem was to develop a web-based tool, PubNet, that is able to visualize concept and theme networks derived from the PubMed literature [72]. [Pg.156]

Our clients in R D groups for stimulating discussions on R D improvement and for requesting and trialing our recent approaches to the simulations of impact and economic assessment of new ways of working and new technology applications in drug discovery. [Pg.272]

Delmon, B. "Recent Approaches To The Anatomy and Physiology of Cobalt Molybdenum Hydrodesulfurization Catalysts" in preprints of Third International Conference on the Chemistry and Uses of Molybdenum, Univ. of Michigan, Ann Arbor, 1979 (Climax Molybdenum Company). [Pg.434]

With only few exceptions, most log P programs refer to the octanol-water system. Based on Rekker s fragmental constant approach, a log P calculation for aliphatic hydrocarbon-water partitioning has been reported [96]. Another more recent approach to alkane-water log P and log D is based on the program VolSurf [97]. It is believed that these values may offer a better predictor for uptake in the brain. [Pg.37]

Gokbuget N, Hoelzer D. Recent approaches in acute lymphoblastic leukemia in adults. Rev Clin Exp Hematol 2002 6 114-141. [Pg.1413]

There are two main scopes for the use of microbiocides in PVC and other polymers. The classical approach is the protection of susceptible plastic material whereas a more recent approach is the achievement of biocidal surfaces. [Pg.103]

A multitude of semiempirical and semiclassical theories have been developed to calculate electron impact ionization cross sections of atoms and atomic ions, with relatively few for the more complicated case of molecular electron impact ionization cross sections. One of the earlier treatments of molecular targets was that of Jain and Khare.38 Two of the more successful recent approaches are the method proposed by Deutsch and Mark and coworkers12-14 and the binary-encounter Bethe method developed by Kim and Rudd.15,16 The observation of a strong correlation between the maximum in the ionization efficiency curve and the polarizability of the target resulted in the semiempirical polarizability model which depends only on the polarizability, ionization potential, and maximum electron impact ionization cross section of the target molecule.39,40 These and other methods will be considered in detail below. [Pg.328]

Recent approaches tend to adopt the uneven discretization of the time horizon of interest wherein each time point along the time horizon coincides with either the start or the end of a task (Schilling and Pantelides, 1996). In addition to accurate representation of time this approach results in much smaller number of time points, hence fewer binary variables, as shown in Fig. 1.8b. [Pg.10]

A more recent approach, which also profits from the synthetic versatility of stabilized thionium ions, has been elaborated by Berard and Piras [22]. These authors observed that the cyclobutane thionium ions 1-76 obtained from the cyclopropyl phenyl sulfides 1-75 by treatment with pTsOH under anhydrous conditions can be trapped by an adjacent electron-rich aromatic ring to give the chromane derivatives 1-77 in good to excellent yields (Scheme 1.20). As expected, 1-77 were obtained as single diastereoisomers with a ds-orientation of the methyl and the phenylthio group as a consequence of steric constraints. [Pg.22]

In a more recent approach, the same group synthesized macrocycles using a Passerini reaction followed by a ring-closing metathesis [23], but the final cycliza-tion gave only low yields. [Pg.545]

Since the anionic triblock copolymers are based on monomers susceptible to this mechanism, one recent approach to this synthesis has been to prepare butadiene-isoprene-butadiene triblock copolymers, which are then hydrogenated so that the high-1,4 polybutadiene end blocks become crystallizable, similar to high-pressure polyethylene (l -5 ). [Pg.102]


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See also in sourсe #XX -- [ Pg.12 ]




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