Layered investigations

The important concept of layered investigations is emphasized by T. Kletz.1 It is a technique that significantly improves the commonly used older methods. Older investigation methods identified only the relatively obvious causes of an accident. Their evidence supported their conclusions, and one or two technical recommendations resulted. According to Kletz, this older method developed recommendations that were relatively superficial. Unfortunately, most accidents are investigated in this style. 

The newer and better method includes a deeper analysis of the facts and additional levels or layers of recommendations. This recommended deeper analysis identifies underlying causes of the accident that are analyzed to develop a multilayered solution to the problem — layered recommendations. 

The number of relevant facts accumulated in an accident investigation is usually limited. Further investigation usually cannot uncover additional facts. A deeper analysis of the facts, however, often leads to new conclusions and recommendations. This deeper analysis is, for example, similar to a brainstorming session to develop new applications for a common house brick. New and interesting applications will continue to surface. 

Kletz emphasized an extra effort to generate three levels of recommendations for preventing and mitigating accidents  

Third layer recommendations to improve the management system. 

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S. Stapf, R. Kimmich 1997, (Translational mobility in surface induced liquid layers investigated by NMR diffusome-try), Chem. Phys. Lett. 275, 261. 

Illustrate the layered investigation process to develop underlying causes of a municipal pool accident. 

Jacobs, E.N. (1939). Preliminary report on laminar-flow airfoils and new methods adopted for airfoil and boundary layer investigations. NACA WR L-345. 

Most of the measurements that have been made of the depth of the deformed layer produced by various preparation procedures are of doubtful significance for one or both of two reasons. Firstly, it. is not certain that the layer investigated is representative of the procedure concerned and free from the residuals of layers produced at early stages of preparation. Secondly, no information is available on the sensitivity of the method used to detect deformation this can have a considerable influence on the depth value determined (see Fig. 5), although the results of any one investigation may still be comparative within themselves. 

We do not know a lot however about the second point, because the deformability of a highly polydisperse brush is not easy to model. We have begun to understand how a monodisperse brush responds to a shear stress [25], and qualitatively we expect these dense structures to be far more rigid than the weakly dense surface layers investigated in 3.2. It is thus plausible that the threshold for the onset of strong slip appears at higher shear rates for dense surface layers than for weakly dense ones, as observed experimentally. Up to now we do not have predictions for the molecular weight dependence of these thresholds. 

In connection with the foregoing, double layers of course also play an important role in electroanalysis. Transfer of. say, electroactive ions through the polarized mercury-solution interface is preceded by passage through the double layer. Therefore current-potential plots depend in principle on double layer properties. Historically, it was his interest In charge-transfer and corrosion problems that induced Grahame to start his seminal double layer Investigations. 

Radeva, T., Petkanchin, 1., and Varogui, R., Electrical and hydrodynamic properties of colloid-polymer surface layers investigated by electro-optics, Langmuir, 9, 170, 1993. 

Vupputuri, R.K., The structure of the natural stratosphere and the impact of chlorofluoromethanes on the ozone layer investigated in a 2-D time dependent model. Pure Appl Geophys 117, 448, 1979. 

Reported studies deal with measurements of the electrode potential of zero charge Epzc [698, 699], double layer investigations [700-702] and studies of electrode reaction mechanisms [703, 704] for an overview, see also [693, 697], Numerous studies (beyond many conducted ex situ) deal with intrinsically conducting polymers, particularly photogenerated mobile charge carriers [705-707]. 

Nag] High angle XRD, X-ray reflectivity, magnetoresistance Cu-NiFe composites. Paramagnetic interfacial layer investigation... 

S. Widmer, "Mixing-layer Investigation", presented at 5th European Turbulence Conference, Siena, Italy, July 5-8,1994. 

Very similar results were obtained in diffusion bilayer solar cells using pyridyl-substituted pyrrolidinofullerenes (PyFs) as electron acceptor components in combination with ZnPc. To fabricate such cells, a concentrated PyF solution was spin coated on top of the evaporated ZnPc layer. Investigation of the obtained bicomponent systems showed that ZnPc becomes partially dissolved under the fabrication conditions. This results in the formation of a diffusion bilayer architecture with the intermediate layer composed of coordination complexes PyF- -ZnPc arranged in between the layers of pristine PyF and ZnPc materials (Figure 41a). Molecular structure of similar coordination complexes of PyFs was proven by X-ray single crystal diffraction. On the contrary, the reference material PCBM does not dissolve phthalocyanine underlayer and does not form any coordination complexes with ZnPc. Therefore, solution deposition of PCBM on the top of ZnPc gives a truly bilayer device. 

For the extended mucin layers investigated here we will use the QCM thickness only as a qualitative indicator where a decrease in thickness means a reduction in water content of the adsorption layer, which in turn indicates a contraction of the layer. In the evaluation we used the reflectometry data of Dedinaite et al. [23] and the true sensed mass reported by Feldoto et al. [11], where both results were obtained for BSM adsorbing on hydrophobic surfaces from 25 ppm solutions in 30 mM NaNOs. The surfaces used by Feldoto et al. are identical to ours, whereas Dedinaite et al. utilized hydrophobized silica. It is plausible that the adsorbed amounts on these two surfaces... 

Nitrogen does not show any influence on the thickness of the oxide layer, investigations of various alloys with different nitrogen contents have confirmed an average thickness of 12-22 A [Mudali Rai, 2004] within all varieties. 

Comparison of the theoretical predictions with computer simulations performed for a strictly the same system models Determination of structural properties of surface layers Investigations of phase transitions in the surface films... 

H. Hibino, H. Kageshima, M. Kotsugi, F. Maeda, F.-Z. Guo, Y. Watanabe, Dependence of electronic properties of epitaxial few-layer graphene on the number of layers investigated by photoelectron emission microscopy. Phys. Rev. B 79, 125431 (2009)... 

Schdnhoff, M., Schwarz, B., Larsson, A., Kuckhng, D. Dynamics in polymer layers investigated by NMR techniques. Progr. Colloid Polym. Sci. 121, 80-87 (2002)... 

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