Histograms, particle size distribution

Fig. 2. TEM images and the corresponding particle size distribution histograms of (a) 6 nm, (b) 7 nm, (c) 8 nm, (d) 9 nm, (e) 10 nm, (f) 11 nm, (g) 12 nm, and (h) 13 nm sized iron nanoparticles showing the one nanometer level increments in diameter. The scale bars at the bottom of the TEM images indicate 20 nm...

Figure 1 represents a particle size distribution histogram. Where a preponderance of smaller particles occurs, the curve is right skewed and where a preponderance of larger particles occurs, the curve is left skewed. The symmetrical histogram is rarely found in practical applications. 

Pt particle size distributions (histograms) measured directly from TEM images are shown in Figure 6. 

The shade of a product is another parameter which is influenced by the particle size (Sec. 1.6.1.2). This is easy to see by comparing the reflection curves of two Pigment Yellow 83 white reductions in an alkyd-melamine resin system. The electron photomicrographs in Fig. 65 and the particle size distribution histograms in Fig. 66 represent these samples. At equal pigment concentration, curve 1 of the two remission curves in Fig. 67 reflects the behavior of the pigment with the smaller... 

Table 6.3 includes particle sizes for bimetallic catalysts determined by TEM. Figure 6.4 shows particle size distribution histograms of PtSn-BM and NiSn-BM bimetallic catalysts and the corresponding Pt and Ni monometallic ones. In all the cases, the sohds were subjected to a hydrogen reduction pretreatment. These... 

The preparation, which is rapid if it concerns dispersing the crushed catalyst on an amorphous carbon film, may take several hours for microtomy. The analysis of a sample in transmission electron microscopy requires several hours of observation if the aim is to ensure that the results are representative. This is particularly important when subsequently seeking to determine particle size distribution histograms. Reliable values of the average size and of the width of the distribution can only be obtained taking into account a number of particles greater than 100. 

Particle size distribution histograms are constructed from the TEM micrographs by converting the image diameters di) into the total number of atoms Np) in a particle using the following equation ... 

Figure 9.5 Transmission electron microscopic image (a) and particle size distribution histogram (b) of a catalyst made using DPU method. (Reprinted with permission from [97]. Copyright 2002 American Chemical Society.)...

Only a few publications have reported the stabihty of Pt/C catalysts for HT-PEM fuel cells, especially PA-doped PBl -membrane-based HT-PEM fuel cells. For example, Liu et al. [52] conducted a 600-hour lifetime test of a PA-doped PBI -membrane-based HT-PEM fuel cell by using commercially available Pt/C as both anode and cathode catalysts. The Pt particle sizes before and after the lifetime test were evaluated by transmission electron microscopy (TEM) measurements. Figure 10.10 shows the TEM images and Pt particle size distribution histograms of the Pt/C catalysts before and after the test. The TEM results reveal that the Pt particle agglomeration occurred at both the anode and the cathode, but more severely on the latter. For the fresh Pt/C catalyst, the Pt particle size distribution was relatively narrow, with a range of 2-5 nm and an... 

FIGURE 10.10 TEM images and Pt particle size distribution histograms of Pt/C catalysts before and after lifetime testing [52]. (For color version of this figure, the reader is referred to the online... 

FIGURE 15.21 Particle size distribution histograms from TEM imaging for samples prepared with addition times of 30 s at pH = 1 (top) and pH = 6.4 (hottom). 

Bulk particulates of various sizes can be analysed to display their particle size distribution and a frequency histogram plotted, as shown in Figure 1.8. 

Figure 3. Transmission electron microphotographs and histograms of the particle size distribution for Pd nanoparticles synthesized at Wo 3 (a) and 7 (b) [23] and isolated via the proposed method.

Histograms of gold particle size distributions are shown in Figure 4. 

Figure 4. Electron micrographs and relative histograms of the particle size distribution of commercial Rh/y-Al203 (Bl) and Rh/y-Al203 (MVS) (B2). (Reprinted from Ref [24], 2003, with permission from Elsevier.)...

Figure 6. Electron micrographs and relative histograms of the particle size distribution of Pd/PDMP (MVS).

Figure 7. Electron micrographs and relative histograms of the particle size distribution of 5% (w/w) of Pt/y-Al203 systems obtained (a) from the solution containing Pt particles with hydrodynamic diameter of 0.9 nm (b) from the solution containing Pt particles with hydrodynamic diameter of 1.5 nm.

Typical HRTEM images of samples calcined at different temperature and then activated at 800°C are reported in Fig.3, along with the histograms of particle size distribution. 

Particle size distribution may be characterized in terms of a spread of values in a table, a graphical representation in the form of a histogram (block diagram), or as... 

A few examples will exemplify the relation between the particle size distribution of a pigment and its lightfastness. Fig. 73 shows histograms of the respective... 

Figures 13.23a and b show the PdO particle size distribution of PdO-supported catalysts prepared from an acidic hydrosol (neutralization of palladium nitrate solution by addition of soda) and a basic one (neutralization of soda by addition of palladium nitrate). Comparisons with the corresponding histograms of the initial suspensions (Figs. 7b and 9b), show that the distributions are not significantly modified. Only a very slight increase of the standard deviation of the dispersion values is observed...

FIGURE 13.28. TEM micrograph and histogram of the PdOSn catalyst and particle size distribution. 

Figure 15.4 Transmission electron microscopy images and size-distribution histograms (300 particles counted) for iridium nanoparticles prepared in (a) BMI BF (b) BMI PFs and (c) BMI CF3SO3. (Reproduced with permission from Ref [25] 2006 Elsevier).

Fig. 2 HRTEM image of G6-Q116(Pd75Au75) DENs formed by the co-complexation method and a histogram of the particle-size distribution. Reprinted with permission from J Am Chem Soc, 2004, 126, 15583-15591. Copyright 2004 American Chemical Society...

Fig. 8 TEM micrograph and histogram (obtained from about 300 nanoparticles) illustrating the particle size distribution of PEIG-stabilized platinum nanoparticles...

Figure lb. Histogram representation of a particle size distribution. Reproduced with permission from Ref. 8. Copyright 1985 Oxford IBH Publishing. 

Average particles area (A), its standard deviation (6A), and particle area histogram (particle size distribution based on area) ... 

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