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Constrained situation

Well-defined stable isotope profiles may be used to provide quantitative information on fluid fluxes such as the direction of fluid flow and the duration of infiltration events (Baumgarmer and Rumble 1988 Bickle and Baker 1990 Cartwright and Valley 1991 Dipple and Ferry 1992 Baumgartner and Valley 2001). In well constrained situations, fluid flow modeling permits estimation of fluid fluxes that are far more realistic than fluid/rock ratios calculated from a zero-dimensional model. [Pg.220]

In the whole range of our experimental conditions, maleic acid has no measurable volatility and we hoped so to obtain more accurate information on the wetting efficiency as well as to check the model in a much more constrained situation. Moreover the direct comparison of this reaction with the very similar hydrogenation of alphamethylstyrene (the volatility of the reactant excepted) which we experienced previously, could directly put into sight the role of dry or badly irrigated catalyst particles. [Pg.21]

Constraining situational behavior is beyond the scope of enterprise management. Enterprises... [Pg.627]

The number of configurations is proportional to the length of the chain. In the case of the unconstrained molecule this has a value / and in the constrained situation a value h. Then the interaction potential Fr is given by... [Pg.299]

The microphase separation of block copolymers in a constrained situation has attracted interest both from experiments and theories. There are several important characters to make this system favorable in fabricating nanoscale features. Firstly, the constrained situation helps confine the dimension of microphase separation into microscale or nanoscale, so the materials formed in such a system spontaneously possess microstructures. Secondly, the constrained situation can suppress the fluctuation of phase separation and help create an ordered pattern at large scale. Thirdly, the surface of the constrained situation can be deliberately modified to direct the microphase separation of block copolymers with attention to make nonbulk structures. [Pg.289]

Geometrically, the constrained situation can be a one-dimensional, two-dimensional, or three-dimensional. Most previous simulation studies concentrated on the... [Pg.289]

Recently, researchers paid more attention to the guided self-assembly of block copolymer thin films on a patterned surface. The patterned surface means the surface of a constrained situation is chemically or physically modified to form a pattern with specific property and size. A series of exquisite structures are found in the microphase separation of block copolymer under the patterned surface. In the theoretic work of Wu and Dzenis [43], they designed two kinds of patterned surface to direct the block copolymer self-assembly (Fig. 15.7). The self-assembled structures are found strongly influenced by the commensurability of polymer bulk period and pattern period. With mismatched patterns on two surfaces, both MC simulation [44] and SCFT researching [45] predicted the titled lamellae and perforated lamellae structures for symmetric diblock copolymers. Petrus et al. carried out a detailed investigation on the microphase separation of symmetric and asymmetric diblock copolymers confined between two planar surfaces using DPD simulation [46,47]. It is found that various nonbulk nanostructures can be fabricated by the nanopatterns on the surfaces. [Pg.290]

In these constrained situations, there are ways in which a confirmed order or an invoice can be used by a firm to fund production cycles. Two possibilities are a supply chain structured-credit finance approach, and invoice discounting or factoring. [Pg.249]

In eontrast, if the eleetron is eonstrained to remain within a fixed area in the x,y plane (e.g., a reetangular or eireular region), then the situation is qualitatively different. Constraining the eleetron to any sueh speeified area gives rise to so-ealled boundary eonditions that impose additional requirements on the above A and B funetions. [Pg.15]

The actual amount and stmcture of this "bound" water has been the subject of debate (83), but the key factor is that in water, PVP and related polymers are water stmcture organi2ers, which is a lower entropy situation (84). Therefore, it is not unexpected that water would play a significant role in the homopolymeri2ation of VP, because the polymer and its reactive terminus are more rigidly constrained in this solvent and termination k is reduced... [Pg.531]

If C is constrained to lie after s, its clobbering effect will not be felt at situation s. This process of constraining C to lie after s is called demotion. [Pg.65]

Step 2. The qualitative value of the desired change is propagated through the steady-state model equations of the plant equipment, following the constraint propagation procedure of Steele (1980). Manipulations that cause the desired change and that are feasible are identified as White Knights and are constrained to lie before the situation of interest s, in accordance with the truth criterion. [Pg.69]

We have characterized our equations and variables as inter- and intra-situational. In transitioning from one state to another, we can view the intersituational equations as constraining the values of the next state s variables. Viewed as constraints, we can define the looseness or tightness of the constraints that values of a state s variables place on the next state. Thus, for example, since the start-times of the units in the next state are constrained to be larger than the end-times of the same unit in the... [Pg.300]

Regarding the electrode/electrolyte interface, it is important to distinguish between two types of electrochemical systems thermodynamically closed (and in equilibrium) and open systems. While the former can be understood by knowing the equilibrium atomic structure of the interface and the electrochemical potentials of all components, open systems require more information, since the electrochemical potentials within the interface are not necessarily constant. Variations could be caused by electrocatalytic reactions locally changing the concentration of the various species. In this chapter, we will focus on the former situation, i.e., interfaces in equilibrium with a bulk electrode and a multicomponent bulk electrolyte, which are both influenced by temperature and pressures/activities, and constrained by a finite voltage between electrode and electrolyte. [Pg.129]

The above constrained parameter estimation problem becomes much more challenging if the location where the constraint must be satisfied, (xo,yo), is not known a priori. This situation arises naturally in the estimation of binary interaction parameters in cubic equations of state (see Chapter 14). Furthermore, the above development can be readily extended to several constraints by introducing an equal number of Lagrange multipliers. [Pg.161]

Pressure drop. Rather than specify a fluid velocity, it is often preferred to specify the pressure drop across the heat exchanger. In retrofit situations, where a new heat exchanger is to be installed in an existing plant, the allowable pressure drop is often highly constrained. This is because in a retrofit situation, it is often desirable to avoid... [Pg.322]


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See also in sourсe #XX -- [ Pg.347 ]




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Situation

Situational

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