DSIMS

The Calculated Value of the Diffusion, Dcai and the Simulated Value [60], Dsim, for Xe in Ne°... 

Due to the saturation of the traps, changes in Q(x) have a super-linear effect on the local charge carrier mobilities. Since the charges have to pass the entire channel, exp/ n sim the effective mobility of the OFET are limited by the locally reduced mobility near the drain electrode, which explains the strong influence of Vr,. Finally, in Figure 8.9(a), the dashed lines indicate the variation of fnexp/ Dsim functiou of giiit at constant values of Vq by variation of Kpi. It can be seen in Figure 8.9(a) that the slopes (d(/n,-xp//ndni)/dQ ... 

The SLD profiles obtained from neutron reflectivity were confirmed using dynamic scanning mass spectroscopy (DSIMS) to measure the fluorine concentration as a function of depth. As can be seen from Fig. 12c, the DSIMS data shows the same qualitative skin-core features as observed by neutron reflectivity [47]. 

Fig. 12 c Comparison of DSIMS and neutron reflectivity data for similar films. The data is consistent with both techniques showing the presence of a high... 

Dsim Modified (center-of-mass) diffusivity in a single-file system... 

Fig.4 Comparison of the concentration profiles of tagged particles obtained by DMC simulations for tracer exchange in single-file systems of length L (oscillating solid lines) with the concentration profiles for normal diffusion, with Dsim and N given in Table 1 (solid lines) at times ti = 0.93 x 10 r, t2 = 2.1 x 10 r, t = 3.7 x 10 , and t4 = 7.6 x 10 r (r is the duration of the elementary diffusion step). From [57] with permission...

Table 1 Results of the best fit Dsim and N and the center-of-mass diffusivity Dgff and site number N in the final time domain of tracer exchange (controlled by center-of-mass diffusion) [57]...

Figure 8 shows the time evolution of interfacial thickness for the PS/dPS bilayer as a function of temperature [40]. The of both PS and dPS was fixed at 29k. The interfacial characterization was made by dynamic secondary ion mass spectroscopy (DSIMS). In the case of aimealing at 400, 393, and 380 K (i.e., above the 7 of 376 K), the interfacial thickness proportionally increased to a half power of the annealing time. This is in good accordance with the context of Fickian diffusion. By contrast, a unique interfacial evolution was observed at 370 K (i.e., between 7 and T ). At first, the bilayer interface monotonically thickened with increasing time,... 

Hyperbranched and comb polymers have also been used as surface active additive. Ariura et al. synthesized by combination of anionic and cationic polymerization a monodispersed hyperbranched polystyrene [73]. The authors proved by combination of DSIMS and neutron reflectivity the preferential surface enrichment of the branched protonated macromolecules when blended with its deuterated linear polystyrene counterparts with the same molar mass. Other systems involving the segregation of the branched macromolecules in binary blends were demonstrated such as in polyamide [74] or poly (methylmethacrylate) [75]. 

Figure 8.15 (a) Concentration profiles of in bilayer samples of P3HT and rf-[60]PCBM annealed for 5 min at different temperatures as measured using dynamic secondary ion mass spectrometry (DSIMS). The thicknesses of the layers were normalized such that 0 nm is the... 

The reptation dynamics and the interface structure relations in Table 2 have been demonstrated experimentally by a series of interdiffusion experiments with selectively deuterated HDH/DHD polymer interfaces using dynamic secondary ion mass spectroscopy (DSIMS - see Secondary ion mass spectrometry) and neutron reflectivity. The scaling laws for interdigitation and the complete concentration profiles for Rouse and reptation dynamics have also been calculated. ... 

The chemical mapping of simple ions such as C, Na, and have been applied to the TOF-SIMS analysis of biological samples of organs, tissues, and cells [22-27,89,90], and 3D images of the elemental distributions [91] have also been obtained. In addition, lateral and 3D distributions of Na+, K+, Ca+, and isotope-labeled elements in cells can be obtained with dynamic secondary ion mass spectrometry (DSIMS) imaging techniques [91,92]. 

DIRECT SAMPLE INTRODUCTION MASS SPECTROMETRY (DSIMS) ANALYSIS OF SURROGATES IN CONTACT WITH PERMEABLE MATERIALS... 

Data Acquisition Once the sample has been successfully inserted, then data acquisition is initiated. Typically, the ionization period is kept as short as possible (1 ms), to minimize the number of ions created in the experiment. Ions are formed, then scanned out continuously (in the positive-ion mode), and hence, mass spectrometry as a function of extraction time is a key feature of the DSIMS experiment. 

Typical DSIMS Results Analysis of DEEP from Polyethylene and Nitrile Rubbers... 

Application of about a microgram of DEEP (as a H2O solution) to the surface of a polyethylene film resulted in absorption of a fraction of the compound into the polymer bulk. DSIMS experiments were initiated after the solvent had dried ( 1 H). The mass spectrum... 

In addition to showing absorption of a significant amount of DEEP, plotting the summed intensity of the [DEEP+H] provides a measurement of the rate of depletion from the polymer (Figure 22.11). The intensities summed with time are shown by the square data points, and the intensities steadily increase through about 800 s of the DSIMS experiment. This plot would... 

FIGURE 22.11 Kinetic plot generated from the DSIMS experiment involving application of DEEP to polyethylene. Square data points are the summed intensity of the [DEEP+H] ions with increasing time in vacuum (t, c)- Circular data points are the inverted values calculated from the summed intensity plots and represent depletion of the DEEP from the polymer. The solid line is plotted from the exponential function that was fitted to the depletion data points. 

Sorption of toxins that are absorbed into the nearsurface bulk of permeable polymers represents one area where substantial improvements in the understanding of contaminant behavior are needed. Applications of the IT-SIMS in the DSIMS mode provide a relatively easy approach for measuring absorbed contamination. 

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