Complex interplay of processes

These activities and impacts arise from a complex interplay of processes that operate at a variety of geographical scales from global to local, and temporal scales from very immediate to very long term. Chains of causality work both from the global scale to the local, as in the case of economic globalization, and from the local to the global, either systemically... 

Within aviation, analyzing the exact causes of accidents and incidents is a nontrivial task. Even if detailed flight data from the black box are available, it is usually still difficult to come up with a clear analysis, for the simple reason that the causes of incidents cannot be attributed to a single point of failure of one individual entity. Instead, most incidents in aviation are found to be caused by a complex interplay of processes at various levels of the socio-technical system, involving pilots, air traffic controllers, technical systems, and their interaction. For example the famous accident in 2009 of Air France Flight 447 is stiU under investigation and seems to have been the consequence of a rare combination of factors. On May 31, 2009, this flight disappeared... 

The theoretical tools discussed in this contribution address various optimization tasks in PEMFC research (i) highest system efficiencies and fuel cell power densities and, thus, minimum overvoltage losses in CCLs (ii) optimum catalyst utilization and, thus, minimal Pt loading (and minimal cost), and (iii) waterhandling capabilities of CCLs and their impact on the water balance of the complete fuel cell. Structural parameters, as well as operating and boundary conditions that control the complex interplay of processes enter at three major levels of the theory. 

Three-phase slurry reactors are commonly used in fine-chemical industries for the catalytic hydrogenation of organic substrates to a variety of products and intermediates (1-2). The most common types of catalysts are precious metals such as Pt and Pd supported on powdered carbon supports (3). The behavior of the gas-liquid-sluny reactors is affected by a complex interplay of multiple variables including the temperature, pressure, stirring rates, feed composition, etc. (1-2,4). Often these types of reactors are operated away from the optimal conditions due to the difficulty in identifying and optimizing the critical variables involved in the process. This not only leads to lost productivity but also increases the cost of down stream processing (purification), and pollution control (undesired by-products). 

The overall performance of the electrochemical processes is determined by the complex interplay of parameters that may be optimized to obtain an effective and economical incineration of pollutants. The principal factors determining the electrolysis performance will be (Pletcher and Walsh 1982) as follows ... 

In the case of gel permeation or size-exclusion HPLC (HP-SEC), selectivity arises from differential migration of the biomolecules as they permeate by diffusion from the bulk mobile phase to within the pore chambers of the stationary phase. Ideally, the stationary phase in HP-SEC has been so prepared that the surface itself has no chemical interaction with the biosolutes, with the extent of retardation simply mediated by the physical nature of the pores, their connectivity, and their tortuosity. In this regard, HP-SEC contrasts with the other modes of HPLC, where the surfaces of the stationary phase have been deliberately modified by chemical procedures by (usually) low molecular weight compounds to enable selective retardation of the biosolutes by adsorptive processes. Ideally, the surface of an interactive HPLC sorbent enables separation to occur by only one retention process, i.e., the stationary phase functions as a monomodal sorbent. In practice with porous materials, this is rarely achieved with the consequence that most adsorption HPLC sorbents exhibit multimodal characteristics. The retention behavior and selectivity of the chromatographic system will thus depend on the nature and magnitude of the complex interplay of intermolecular forces... 

There is a complex interplay of kinetic processes in these energy transfer lasers. The conditions under which they operate are extreme in terms of the concentrations of transient species and the local gas temperatures. Many of the key reactions are difficult to study in isolation as they involve interactions between pairs of radicals or other transient species (e.g. collisions between electronically and vibrationally excited molecules). The impetus to obtain mechanistic and kinetic data for chemical laser systems (potential as well as demonstrated) has stimulated the development of new experimental techniques and produced a substantial body of kinetic data. Beyond the practical value of this work, the kinetic data that have been obtained are of fundamental scientific interest. They provide insights regarding the underlying principles that govern energy transfer processes and rare examples of reactions involving electronically and/or vibrationally excited species. 

A catalytic process is a complex interplay of mnltiple phenomena, including the flow of reactive mixtures through a reactor, the respective diffusion of reactants and prodncts to and away from active sites, and the chemical transformation of reactants into prodncts at the active sites. Aside from issnes related to the transport and chemical transformations of reactants and prodncts, it is also necessary to manage the heat load in a catalytic system. In principle, any of the above-mentioned phenomena can be manipulated to affect the outcome of a catalytic reaction. 

The concentration of glucose in the blood is regulated by a complex interplay of multiple pathways, modulated by a number of hormones. Glycogenesis is the conversion of glucose to glycogen. The reverse process, namely the break-... 

What can late Archaean sedimentary basins tell us about the early Earth system1 Sedimentary basins develop as a response to the interaction between sediment supply and crustal subsidence. In detail this reflects the complex interplay of tectonism, magmatism, eustasy and weathering rates, which are themselves a function of paleoclimate (Eriksson et al., 2001). In the late Archaean probably a number of these factors were different from the modern. For example there is evidence that climatic regimes were different and so it is likely that weathering rates and sediment supply were also different (Chapter 5, Section 5.3.2.1). In addition, many believe that the mantle was hotter at this time. If this is the case then tectonic processes and subsidence rates would also be different from those of modern sedimentary basins. 

The basis of the surface modification of electrodes by adatoms has been delineated by selected examples with regard to the oxidation and reduction processes of small organic molecules in aqueous medium. The complex interplay of surface adatoms favors the electroactivity of a determined species, and delivers some insights as to the mechanism of such organic molecules in favor of a product with an added value. 

In response to vascular injury, the body must tightly seal the leakage while preventing unrestrained intravascular clot development and vessel occlusion. The coagulation process is a complex interplay of the blood vessel wall, platelets and other blood cells, as well as many soluble plasma proteins ( coagulation factors [16]). In the ultimate step of the coagulation cascade, the trypsin-hke serine proteinase thrombin (factor Ila) is released into the blood stream, where it performs several es-... 

Adsorption of proteins onto surfaces involves a complex interplay of reversibility, exchange, conformational change, irreversible attachment, and denaturation. Several of these processes may be followed by measurement of the circular dichroism of adsorbed species and of desorbed material. The profile of chromatographically adsorbed material also contains, in principle, the details of the complex kinetics. Some aspects of each of these processes are examined. 

However, in either of these microphysical approaches, the complex interplay of the action of an electric (and possibly of an additional magnetic) field and of elastic and various inelastic electron collision processes with atoms or molecules of the gas has to be taken into account in detail. 

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