Design schemes generation

Figure 5.13 Number of design schemes generated at system and subsystem level (Andersson, 1994)...

It will be apparent from the discussions in the previous sections that an absolute value of reliability is at best an educated guess. However, the risk of failure determined is a quantitative measure in terms of safety and reliability by which various parts can be defined and compared (Freudenthal et al., 1966). In developing a reliable product, a number of design schemes should be generated to explore each for their... 

The approach chosen by Schostarez and Paquette (Scheme XCII) was fully regio-controUed and designed to generate modhephene and epimodhephene independently Bicyclic enone 787 was transformed by conju te addition into 788 or 789. When the first sutetrate was thermolyzed, ene chemistry locked the condary methyl sub-... 

Initially, the protein-like HP sequences were generated in [18] for the lattice chains of N = 512 monomeric units (statistical segments), using for simulations a Monte Carlo method and the lattice bond-fluctuation model [34], When the chain is a random (quasirandom) heteropolymer, an average over many different sequence distributions must be carried out explicitly to produce the final properties. Therefore, the sequence design scheme was repeated many times, and the results were averaged over different initial configurations. 

For illustration, let us estimate the dispersion error of the aforementioned narrow-band technique and compare it with the one induced by the wideband method of (2.107)—(2.115). The cell dimensions are chosen as Ay = 2Ax and T2D = 0-85 in (5.46). Figure 5.5 gives the results for two mesh resolutions with respect to Ax. In contrast with the performance of the latter scheme, the narrow-band approach achieves a remarkable reduction around the design frequency, whereas its accuracy deteriorates at finer resolutions. This is, however, not a serious shortcoming, since a given computational domain appears to have a smaller electrical size at lower frequencies and, consequently, the dispersion error is not as considerable as in the high-frequency band. Moreover, it is noteworthy to observe that the narrow-band scheme generates smaller errors for coarser lattices and thus, its application to broadband simulations should not be ruled out. 

Two phosphole-3-carboxylates with 4,5-diphenyl substituents ((276) and (277)) have been prepared by a rather specialized approach <93BSF695>, outlined in Scheme 85. This method was designed to generate phospholide ions with a C-functional group (e.g. (278)), but the ions can be alkylated on P to form phospholes. The ions are formed by a base-induced retro-Michael reaction. While of value in producing an otherwise inaccessible substitution pattern on the ring, the method is less... 

This scheme is designed to generate groups of minima that are in local equilibrium on a timescale determined by the choice of the barrier height, In the appli-... 

Interestingly, none of the stereoselective reactions described previously assembles a new chiral center instead, the applied strategies rely on previously existing, special chiral characteristics of the substrates (prochiral moieties or fluxional axial chirahty). In contrast to these approaches, a recently published report relies solely on catalyst design to generate a new stereocenter in the product through chelate-assisted hydroarylation (Scheme 23.54) [166]. The most selective Rh catalyst 31 uses a biaryl-substituted Cp ring as the structural element to induce enantioselectivity. After the reaction, the hydroarylation product with a new quaternary stereocenter can be isolated in 87% yield and 91% ee. 

Using the Gmbbs second-generation catalyst, the product of cross-metathesis is the f-isomer. Some specialized Z-selective catalysts have been designed (Scheme 8.92). ° ... 

A novel assay system [17] was designed to generate D-X5P from o-xylulose in situ (Scheme 15.4,leftpart). For this purpose, the commercially unavailable xylulokinase (XK) from S. cereuisiae was overexpressed in E. coU and purified in a single step. 

The use of a well known and mastered design scheme with a compact modular layout of the primary circuit in which short nozzles connect the main plant equipment (reactor, steam generator, MCP), is the main factor contributing to improvement of the technical and economic characteristics of the VBER-300. Such a design provides minimal mass and overall dimensions of the primary circuit, reduces the primary piping, minimizes the construction scope of the reactor compartment and consequently, reduces the capital construction investment per unit. 

Tentative training scheme for the development and pre-conceptual design of Generation-IV nuclear reactors (preliminary version—Euratom, 2011)... 

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