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Rigid variable

The chemistry of adamantane and related cage-like hydrocarbons has developed rapidly in recent years. These developments, encompassing a broad spectrum of the chemical world, have not been stimulated by any unique properties associated with the cage strutures of these molecules the chemistry of such systems is typically hydrocarbon in nature. The particular utility of cage-like substrates in a variety of chemical investigations arises, for the most part, from their conformational rigidity variables (e.g. those associated with structure) appropriate to more mobile compounds are often eliminated by the use of cage-like systems. The availability, ease of functionalization, and the near ideal structure of adamantane make it extremely useful for this purpose. [Pg.90]

A state formula is a formula from an underlying logic language, here normal predicate logic, that can be evaluated at an individual state of a sequence. In the present application, a state formula is therefore a formula about the variables events and connections in any given round and any number of auxiliary variables. The auxiliary variables are so-called rigid variables, i.e., they are assumed to have the same value in all rounds see, for instance, the use of the message variable m below. [Pg.76]

The only exception is that authentication need not work if the message bound N has been reached. Expressing this condition in temporal. logic is probably not the most natural way, but it can be done with a flexible variable counter (i.e., counter may assume different values in different rounds — this is the opposite of a rigid variable), which is formally used to count executions of authentication. [Pg.86]

Parkinsonism Bradykinesia, rigidity, variable 5-30 days can recur even Antagonism of Antiparkinsonian agents helpful ... [Pg.304]

Apart from chemical composition, an important variable in the description of emulsions is the volume fraction, outer phase. For spherical droplets, of radius a, the volume fraction is given by the number density, n, times the spherical volume, 0 = Ava nl2>. It is easy to show that the maximum packing fraction of spheres is 0 = 0.74 (see Problem XIV-2). Many physical properties of emulsions can be characterized by their volume fraction. The viscosity of a dilute suspension of rigid spheres is an example where the Einstein limiting law is [2]... [Pg.501]

The key to these more efficient treatments is a natural canonical formulation of the rigid body dynamics in terms of rotation matrices. The orientational term of the Lagrangian in these variables can be written simply as... [Pg.352]

A Hamiltonian version of the quaternionic description is also possible by viewing the quaternions as a set of generalized coordinates, introducing those variables into the rigid body Lagrangian (1), and finally determining the canonical momenta through the formula... [Pg.355]

Those stmctural variables most important to the tensile properties are polymer composition, density, and cell shape. Variation with use temperature has also been characterized (157). Flexural strength and modulus of rigid foams both increase with increasing density in the same manner as the compressive and tensile properties. More specific data on particular foams are available from manufacturers Hterature and in References 22,59,60,131 and 156. Shear strength and modulus of rigid foams depend on the polymer composition and state, density, and cell shape. The shear properties increase with increasing density and with decreasing temperature (157). [Pg.412]

Polymeric isocyanates or PMDI ate cmde products that vary in exact composition. The main constituents are 40—60% 4,4 -MDI the remainder is the other isomers of MDI, trimeric species, and higher molecular weight oligomers. Important product variables are functionaHty and acidity. Rigid polyurethane foams are mainly manufactured from PMDI. The so-called pure MDI is a low melting soHd that is used for high performance polyurethane elastomers and spandex fibers. Liquid MDI products are used in RIM polyurethane elastomers. [Pg.344]

Processes in which solids play a rate-determining role have as their principal kinetic factors the existence of chemical potential gradients, and diffusive mass and heat transfer in materials with rigid structures. The atomic structures of the phases involved in any process and their thermodynamic stabilities have important effects on drese properties, since they result from tire distribution of electrons and ions during tire process. In metallic phases it is the diffusive and thermal capacities of the ion cores which are prevalent, the electrons determining the thermal conduction, whereas it is the ionic charge and the valencies of tire species involved in iron-metallic systems which are important in the diffusive and the electronic behaviour of these solids, especially in the case of variable valency ions, while the ions determine the rate of heat conduction. [Pg.148]

In Section 5.2 the set of internal state variables k was introduced. In the referential theory, a similar set of referential internal state variables K will be introduced in the same way without further physical identification at this stage. It will merely be assumed that each member of the set K is invariant under the coordinate transformation (A.50) representing a rigid rotation and translation of the coordinate frame. [Pg.154]

The square-section beam of length / (determined by the design of the structure, and thus fixed) and thickness t (a variable) is held rigidly at one end while a force F (the maximum service force) is applied to the other, as shown in Fig. 7.4. The same texts that list the deflection of discs give equations for the elastic deflection of beams. The formula we want is... [Pg.71]

Common-cause or inherent variability is due to the set of factors that are inherent in a machine/process by virtue of its design, construction and the nature of its operation, for example, positional repeatability, machine rigidity, which cannot be removed without undue expense and/or process redesign. [Pg.288]

Other artifacts that have been mentioned arise from the sensitivity of STM to local electronic structure, and the sensitivity of SFM to the rigidity of the sample s surface. Regions of variable conductivity will be convolved with topographic features in STM, and soft surfaces can deform under the pressure of the SFM tip. The latter can be addressed by operating SFM in the attractive mode, at some sacrifice in the lateral resolution. A limitation of both techniques is their inability to distinguish among atomic species, except in a limited number of circumstances with STM microscopy. [Pg.96]


See other pages where Rigid variable is mentioned: [Pg.181]    [Pg.894]    [Pg.2496]    [Pg.349]    [Pg.349]    [Pg.350]    [Pg.351]    [Pg.351]    [Pg.352]    [Pg.355]    [Pg.357]    [Pg.354]    [Pg.159]    [Pg.521]    [Pg.222]    [Pg.866]    [Pg.159]    [Pg.652]    [Pg.412]    [Pg.413]    [Pg.402]    [Pg.420]    [Pg.334]    [Pg.103]    [Pg.1744]    [Pg.316]    [Pg.120]    [Pg.121]    [Pg.124]    [Pg.158]    [Pg.280]    [Pg.281]    [Pg.39]    [Pg.206]    [Pg.391]    [Pg.355]   
See also in sourсe #XX -- [ Pg.76 ]




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