Near-field analysis

The formulation of Section 9.5.1 has served to remove the chemistry from the field equations, replacing it by suitable jump conditions across the reaction sheet. The expansion for small S/l, subsequently serves to separate the problem further into near-field and far-field problems. The domains of the near-field problems extend over a characteristic distance of order S on each side of the reaction sheet. The domains of the far-field problems extend upstream and downstream from those of the near-field problems over characteristic distances of orders from to /. Thus the near-field problems pertain to the entire wrinkled flame, and the far-field problems pertain to the regions of hydrodynamic adjustment on each side of the flame in essentially constant-density turbulent flow. Either matched asymptotic expansions or multiple-scale techniques are employed to connect the near-field and far-field problems. The near-field analysis has been completed for a one-reactant system with allowance made for a constant Lewis number differing from unity (by an amount of order l/P) for ideal gases with constant specific heats and constant thermal conductivities and coefficients of viscosity [122], [124], [125] the results have been extended to ideal gases with constant specific heats and constant Lewis and Prandtl numbers but thermal conductivities that vary with temperature [126]. The far-field analysis has been... 

The near-field analysis provides expressions for the wrinkled-flame motion and the reaction-sheet temperature in terms of the flame shape and the gas velocities at the edge of the wrinkled flame. To the first order in the small parameter bj, the equation for the flame motion may be written, in the nondimensional notation of Section 9.5.1, as... 

On the other hand, the coupled processes in the far field are described in this chapter based on the results of the near field analysis. Assuming that mechanical behavior and unsaturated flow are negligible for regional groundwater flow system, only coupled thermal and hydraulic processes in saturated zone are considered. Governing equation... 

A nano-light-source generated on the metallic nano-tip induces a variety of optical phenomena in a nano-volume. Hence, nano-analysis, nano-identification and nanoimaging are achieved by combining the near-field technique with many kinds of spectroscopy. The use of a metallic nano-tip applied to nanoscale spectroscopy, for example, Raman spectroscopy [9], two-photon fluorescence spectroscopy [13] and infrared absorption spectroscopy [14], was reported in 1999. We have incorporated Raman spectroscopy with tip-enhanced near-field microscopy for the direct observation of molecules. In this section, we will give a brief introduction to Raman spectroscopy and demonstrate our experimental nano-Raman spectroscopy and imaging results. Furthermore, we will describe the improvement of spatial resolution... 

Watanabe, H., Ishida, Y., Hayazawa, N Inouye, Y. and Kawata, S. (2004) Tip-enhanced near-field Raman analysis... 

In the present review, first we will describe how to fabricate artificial photosynthetic reaction center in nanometer scales by making use of phase separation in mixed monolayers of hydrocarbon (HC) and fluorocarbon (FC) amphiphiles [2,5,20-26] as shown in Fig. 2b [3]. The phase separated structures were studied by SPMs such as AFM, SSPM, and scanning near-field optical/atomic force microscopy (SNOAM) [27-33] as well as a conventional local surface analysis by SIMS [3,5], The model anionic and cationic HC amphiphilic... 

Tan W. and Kopelman R. (1996) Nanoscale Imaging and Sensing by Near-Field Optics, in Wang X. F. and Herman B. (Eds), Fluorescence Imaging Spectroscopy and Microscopy, Chemical Analysis Series, Vol. 137, John Wiley Sons, New York, pp. 407-75. 

The application of a laser in mass spectrometers offers the possibility of a direct microlocal analysis with a lateral resolution down to the (tm range. The capability of near-field LA-ICP-MS (NF-LA-ICP-MS)65 created in the author s laboratory provides local information on inhomogeneous element distribution on solid sample surfaces with a spatial resolution in the sub-p,m range. 

The development of surface analytical techniques such as LA-ICP-MS, GDMS and SIMS focuses on improvements to sensitivity and detection limits in order to obtain precise and accurate analytical data. With respect to surface analytical investigations, an improvement of spatial and depth resolution is required, e.g., by the establishment of a near field effect or the apphcation of fs lasers in LA-ICP-MS. There is a need for the improvement of analytical techniques in the (j,m and nm range, in depth profiling analysis and especially in imaging mass spectrometry techniques to perform surface analyses faster and provide more accurate data on different materials to produce quantitative 3D elemental, isotopic and molecular distribution patterns of increased areas of interest with high spatial and depth resolution over an acceptable analysis time. 

Other Effects. In the very near-field, dissolution of the waste form may lead to local changes in pH and Eh. In addition, radiolysis effects in this region also may be important. The consequences of these factors are not addressed in this study because their effects are extremely localized and such a detailed analysis of solubility and speciation is beyond the scope of this paper. 

---