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Restriction connectivity

As a result of the preceding discussion, it appears that, from a physical point of view, the connected partition functions or the connected restricted partition functions are the only interesting quantities. They have a limit when V- oc, and in what follows we shall study only this limit, representing a partition function by the symbol +J (S1,. . . , SN) and a restricted partition function by ... [Pg.382]

Let us now consider partition functions in reciprocal space. The Fourier transform of a (connected) restricted partition function can be expressed as... [Pg.383]

In most cases the different constituent blocks are incompatible, giving rise to intramolecular phase separation, but the chemical connectivity restricts the special dimension of phase segregation to the nanoscale. As a result, at sufficiently high molecular weight, monodisperse block copolymers form a rich variety of self-assembled structures or an array of periodic nanostructures with a periodicity of 10-100 nm, commonly referred to as microphase-separated structures. By changing the relative composition, the compatibility between the component polymers, and the architecture of the copolymer molecules, the size and type of nanostructures can be precisely controlled [1-6]. [Pg.223]

This ensures the correct connection between the one-dimensional Kramers model in the regime of large friction and multidimensional imimolecular rate theory in that of low friction, where Kramers model is known to be incorrect as it is restricted to the energy diflfiision limit. For low damping, equation (A3.6.29) reduces to the Lindemann-Flinshelwood expression, while in the case of very large damping, it attains the Smoluchowski limit... [Pg.849]

After return to the Commander window, the reaction retrieval may be executed separately 629 Dicls-Aldcr reactions between aliphatic dienes and cyclic dicno-pliiles are found. This partial result can be narrowed down by restricting tlie reaction conditions by means of the fact editor, The search field codes for the yield and the temperature can be found to be RX.NYD and RX.T, respectively, either by browsing the database structure or by applying the Find option, as described in the first example. To ensure that the retrieved reaction conditions belong to the same experiment, both search terms must be connected by means of the PROXIMITY operator. Before the retrieval is started, the option "Refine results in... [Pg.255]

The selectivity relationship merely expresses the proportionality between intermolecular and intramolecular selectivities in electrophilic substitution, and it is not surprising that these quantities should be related. There are examples of related reactions in which connections between selectivity and reactivity have been demonstrated. For example, the ratio of the rates of reaction with the azide anion and water of the triphenylmethyl, diphenylmethyl and tert-butyl carbonium ions were 2-8x10 , 2-4x10 and 3-9 respectively the selectivities of the ions decrease as the reactivities increase. The existence, under very restricted and closely related conditions, of a relationship between reactivity and selectivity in the reactions mentioned above, does not permit the assumption that a similar relationship holds over the wide range of different electrophilic aromatic substitutions. In these substitution reactions a difficulty arises in defining the concept of reactivity it is not sufficient to assume that the reactivity of an electrophile is related... [Pg.141]

As a vessel is loaded, it moves downward because of deflection of the load cells and support stmcture. Pipes rigidly attached to a vessel restrict its free movement and assume some portion of the load that cannot be measured by the load cells. This is very detrimental to scale accuracy. Deflection of the load cell is unavoidable deflection of the vessel support stmcture should be minimized. Anything which increases vessel deflection, eg, mbber pads used for shock protection, must be avoided. The total number of pipes should be minimized and be of the smallest diameter, thinnest wall possible. Pipe mns to weigh vessels must be horizontal and the first pipe support should be as far as possible from the vessel. Alternatively, a section of mbber hose or flexible bellows should be used to make the final connection to the vessel. The scale should be caUbrated using weights, not by means of an electrical simulation method, which cannot account for the effects of the piping or test the correct functioning of the scale. [Pg.337]

The steric bulk of the three iodine atoms in the 2,4,6-triiodoben2ene system and the amide nature of the 1,3,5-substituents yield rotational isomers of the 5-A/-acyl-substituted 2,4,6-triiodoisophthalamides. Rotational motion in the bonds connecting the side chains and the aromatic ring is restricted. These compounds also exhibit stereoisomerism when chiral carbon atoms are present on side chains. (R,5)-3-Amino-l,2-propanediol is incorporated in the synthesis of iohexol (11) and ioversol (12) and an (3)-2-hydroxypropanoyl group is used in the synthesis of iopamidol (10). Consequendy, the resulting products contain a mixture of stereoisomers, ie, meso-isomers, or an optical isomer. [Pg.466]

As mentioned previously, ternaiy mixtures can be represented by 125 different residue curve maps or distillation region diagrams. However, feasible distillation sequences using the first approach can be developed for breaking homogeneous binaiy azeotropes by the addition of a third component only for those more restricted systems that do not have a distillation boundaiy connected to the azeotrope and for which one of the original components is a node. For example, from... [Pg.1307]

A delta-connected or an ungrounded star-connected winding should also be protected through a restricted ground fault scheme, otherwise it will remain unprotected. There is no zero sequence or residual current in such a winding to detect a ground fault. [Pg.690]

This is the most common scheme in normal use for any power system with more than one feeder, connected to a common bus, such as for distribution and sub-distribution power networks, having a number of load points, controlled through a main incoming feeder. In a switchgear assembly, for instance, common protection may be provided at the incoming for a ground fault or combined 0/C and G/F protections as discussed above. In such cases, a restricted G/F protection may not be appropriate or required, as the protection now needed is sy.stem protection, rather than individual equipment proteelion. The incomer must operate whenever a fault occurs at any point on the system. Moreover, for an LT system, where it may not be desirable or possible to provide individual protection to each feeder, such a scheme is adopted extensively. [Pg.690]

New types of anodes have been developed and tested as shown in Fig. 16-5 to improve the possibility of maintenance and repair. They can be lifted onto a ship and repaired. The connecting cables are also replaceable. In shallow water, the anchorage must be accurately calculated because considerable dynamic stressing can occur in heavy seas. The ocean floor must be suitable for long-term anchorage. No supply ships must anchor in the area around the platform. This requirement alone often prevents the installation of impressed current anodes since the operator does not wish or is not able to restrict himself to these conditions. [Pg.375]


See other pages where Restriction connectivity is mentioned: [Pg.294]    [Pg.499]    [Pg.503]    [Pg.243]    [Pg.29]    [Pg.294]    [Pg.499]    [Pg.503]    [Pg.243]    [Pg.29]    [Pg.8]    [Pg.65]    [Pg.2538]    [Pg.310]    [Pg.382]    [Pg.166]    [Pg.401]    [Pg.103]    [Pg.516]    [Pg.440]    [Pg.557]    [Pg.706]    [Pg.219]    [Pg.16]    [Pg.352]    [Pg.361]    [Pg.463]    [Pg.247]    [Pg.230]    [Pg.1813]    [Pg.183]    [Pg.464]    [Pg.672]    [Pg.10]    [Pg.338]    [Pg.358]    [Pg.8]    [Pg.66]    [Pg.57]    [Pg.199]    [Pg.200]    [Pg.236]    [Pg.78]    [Pg.77]   
See also in sourсe #XX -- [ Pg.182 ]




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