Unresolved Questions

Isobutane shows the usual NTC and cool flame phenomena (78,154,157,158). As the pressure is iacreased, the expected iacrease ia oxygenated products retaining the parent carbon skeleton is observed (96). Under similar conditions, isobutane oxidizes more slowly than / -butane (159). There are stUl important unresolved questions concerning isobutane VPO (160). 

Application A frequency count of workers was tabulated according to the number of defective items that they produced. An unresolved question is whether the observed distribution is a Poisson distribution. That is, do observed and expected frequencies agree within chance variation ... 

One of the main scientific issues of the discovery of the bucky-onions is the unresolved question of minimal energy configuration of carbon clusters (onion-... 

The major unresolved questions for these systems are the coalescence and flocculation of particles under mechanical agitation and the parameters which influence copolymer composition drift. 

But there are two important unresolved questions regarding the mechanism of crystallization the first question is are the primary nuclei actually formed from the earliest stage ( induction period ) of crystallization and the second is what is the role of the topological nature of polymers in the polymer crystallization mechanism ... 

Therefore, the unresolved question remains of whether chronic, recurring inflammation is the result of a persistent infection with a specific pathogen, an exaggerated exposure to resident normal luminal bacteria products because of increased intestinal permeability or alteration of mucus composition, or an abnormally aggressive immune response to luminal components. 

Great progress has been made toward understanding hydrogen-related complexes in semiconductors. Vibrational spectroscopy has played an important role in the determination of the structures and properties of these defects. Here, some of the unresolved questions discussed in this chapter are summarized. 

In connection with practical situations where CO oxidation is important, we must also consider the perennial question of how to connect the low pressure results onto those at high pressure. Qualitatively this has been done for the CO oxidation reaction but it would still be worthwhile to attempt a numerical prediction of high pressure results based on low-pressure rate parameters. A very nice paper modeling steady-state CO oxidation data over a supported Pt catalyst at CO and O2 pressures of several torr has very recently appeared (.25). Extension of this work to other systems in warranted and, even though unresolved questions continue to exist, every indication is that the high and low pressure data can be reliably modeled with the same rate parameters if no adsorption - desorption equilibria are assumed. 

Z. Lukaszewski, Resolved and Unresolved Questions of Analysis of Surfactants in the Aquatic Environment Adsorption and Its Applications in Industry and Environmental Protection, Vol II Applications in Environmental Protection, Vol. 120, Elsevier Science, Amsterdam, 1999, pp. 135-176. 

How these different perceptions can be made more similar is a very major unresolved question. Unless there can be some progress on this paradoxical situation it will be very difficult to communicate work on many of the areas covered in this book to the general public. 

One unresolved question is whether CENP-A effects the stability of centromeric chromatin. One interesting possibility is that CENP-A promotes an unusually stable chromatin structure that is adapted to withstanding the forces exerted on the centromere during chromosome segregation [23]. Reconstitution of nucleosome arrays with CENP-A may provide insights into this question. 

I have presented an overview of the current state-of-the-art in studies of the Mn complex in photosystem II. There are many unresolved questions and a clear picture of the structure and function of Mn in photosynthetic water oxidation is still not available. One useful approach to help determine the structure of the Mn complex in photosystem II involves the synthesis and characterization of Mn model complexes for comparison with the properties of the Mn complex in photosystem II. Recently, several tetrameric high-valent Mn-oxo complexes have been reported (see the chapter in this volume by G. Christou). Further characterization of existing and new high-valent tetrameric Mn-oxo model complexes, especially EPR and EXAFS measurements, will no doubt help clarify the present uncertain picture of the structure of the Mn complex in photosystem II. 

As has been clearly demonstrated, pi05 has two distinct ubiquitin system targeting motifs, an acidic domain that contains also the Lys residues essential for ubiquitin anchoring, and a C-terminal phosphorylation/E3-binding domain. An important, yet unresolved, question involves the biological rationale behind the evolution of these two sites. To resolve this... 

Abstract. An application of the Rayleigh-Ritz variational method to solving the Dirac-Coulomb equation, although resulted in many successful implementations, is far from being trivial and there are still many unresolved questions. Usually, the variational principle is applied to this equation in the standard, Dirac-Pauli, representation. All observables derived from the Dirac equation are invariant with respect to the choice of the representation (i.e. to a similarity transformation in the four-dimensional spinor space). However, in order to control the behavior of the variational energy, the trial functions are subjected to several conditions, as for example the kinetic balance condition. These conditions are usually representation-dependent. The aim of this work is an analysis of some consequences of this dependence. 

Since the nature of time is itself an unresolved question, we take a simple approach in order to arrive at a mechanism generating the flow of an object through time. ... 

A feature of this overview has been to highlight the progress of combined biological and chemical analysis in the characterization of waterborne organics. The major social impetus for such work has been unresolved questions on the biological side. What are the risks posed by these organics, primarily to human health and also to the environment ... 

Norbert Berkowitz I think the kinetic treatment of the experimental data is of questionable validity. The extraction process is evidently accompanied by considerable changes in the geometry of the coal particles (e.g., swelling and dispersion) there is the unresolved question of whether the extract forms a solution or dispersion finally, there is an obvious but somewhat indefinite effect of coal decomposition. The latter point alone would make determining a temperature effect (and hence, calculating an activation energy ) very difficult practically, if not impossible. 

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