Size-dependent polarization

Figure 9 shows the minimum lubricant him thickness as a function of velocity, with or without micro-polarity. The him thickness curves with micro-polarity are larger than those with the nonpolar molecules. This means that the microstructure and microrotation will have an influence on the him thickness. The simple exponential relation between him thickness and velocity, which holds in EHL, is no longer valid for thin him lubrication if the microstructure and the microrotation are taken into account. However, if the minimum him thickness is sufficiently large, as the velocity increases, the discrepancy between results with and without the consideration of the polar effect is very small. With an increase in both the characteristic length Z and coupling number N, the minimum him thickness becomes much larger than that of the nonpolar case. This reveals a size-dependent effect which accords well with experimental re-... 

Magyar, R.J., Mujica, V., Marquez, M. and Gonzalez, C. (2007) Density-functional study of magnetism in bare Au nanodusters Evidence of permanent size-dependent spin polarization without geometry relaxation. Physical Review B -Condensed Matter, 75,144421-1—144421-7. 

Walter HJ, Rutgers van der Loeff MM, Hoeltzen H (1997) Etrhanced scavenging of Pa relative to h in the South Atlantic south of the Polar front Implicatiotts for the use of the Pa/ h ratio as a paleoproductivity proxy. Earth Planet Sci Lett 149 85-100 Wheatcroft RA (1992) Experimental tests for particle size-dependant biotirrbidation in the deep oceans. Linmol Oceanogr 37(1) 90-104... 

Y Horibe, K Hosoya, KJ Kim, T Ogiso, VHL Lee. (1997). Polar solute transport across the pigmented rabbit conjunctiva Size dependence and the influence of 8-bromo cyclic adenosine monophosphate. Pharm Res 14 1246-1251. 

Considering that the choice of extractant depends on the size and polarity of the analyte of interest, what extractant would be used to extract all the hydrocarbons from a fuel-contaminated soil Would the type of fuel spilled make a difference in the type of extractant used If so, how ... 

In the previous section, we demonstrated the micrometer droplet size dependence of the ET rate across a microdroplet/water interface. Beside ET reactions, interfacial mass transfer (MT) processes are also expected to depend on the droplet size. MT of ions across a polarized liquid/liquid interface have been studied by various electrochemical techniques [9-15,87], However, the techniques are disadvantageous to obtain an inside look at MT across a microspherical liquid/liquid interface, since the shape of the spherical interface varies by the change in an interfacial tension during electrochemical measurements. Direct measurements of single droplets possessing a nonpolarized liquid/liquid interface are necessary to elucidate the interfacial MT processes. On the basis of the laser trapping-electrochemistry technique, we discuss MT processes of ferrocene derivatives (FeCp-X) across a micro-oil-droplet/water interface in detail and demonstrate a droplet size dependence of the MT rate. 

It seems reasonable that molecules of a surfactant may diffuse from the spray droplet into the cuticle of leaves perhaps via imperfections and cracks and then align themselves in monolayers with their nonpolar ends oriented in the cutin and wax. The polar ends will thus also form a layer whose size depends on the length of the hydrophilic chain of the surfactant molecule. These layers or hydrophilic channels will presumably attract water, causing swelling of the cuticle, and thus channels or pores are formed along which herbicide molecules can diffuse according to their various chemical properties (solubility, residual chemical charge, polar properties, etc.). 

Variable-temperature NMR spectroscopy is a well-established technique in the study of conformational exchange kinetics in liquid amides. [7,58] Using DNMR spectroscopy, it is possible to measure the temperature dependence of interconversion rates in order to yield a complete set of kinetic parameters characterizing the internal rotation about the carbon-nitrogen bond. In the last several years, the development of gas-phase NMR methods has provided a valuable tool for the elucidation of the magnitude of intrinsic and environmental contributions associated with this conformational exchange. In order to characterize these contributions, a series of molecules with systematic variations in substituent size and polarity must be analyzed both in the liquid and gas phase. 

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