Discussion Sol of zirconium hydroxocomplexes Figure 2 illustrates distribution PF-6463922 mouse of particle
size in sol. The curve demonstrates two maxima at r p = 7.5 nm (particles I) and 60 nm (particles II). Minimal particle radius has been found as 2 nm. Different particles of the solid constituent of sol are seen in the inset of Figure 2. The smallest nanoparticles are ideally spherical. The shape of particles II is also close to spherical, but their surface is rough. Figure 2 Particle size distribution in sol of insoluble zirconium hydroxocomplexes. Insets: TEM images of the solid constituent of dehydrated sol. Left corner, single nanoparticles; right corner, aggregated nanoparticles. During sol formation, fragmentation and defragmentation of nanoparticles occur simultaneously . As a result, sol
can contain several types of particles . The first one is non-aggregated particles; their merging selleck inhibitor leads to formation of larger ones. Structure of membranes Spheres of micron size are seen in the scanning electron microscopy (SEM) image of the TiO2 sample (Figure 3a). The particles are distorted due to annealing and pressure during ceramics preparation. Widening and narrowing of spaces between the ATPase inhibitor globules are also visible. Globular HZD particles on the internal surface of the membrane are seen for the TiO2 -HZD-2 sample (Figure 3b). However, increase of the matrix mass after modification is inconsiderable (Table 1).The transmission electron microscopy (TEM) image of powder of the pristine membrane is given in Figure 4a. No smaller constituents are visible inside the particles. We can separate three types Thalidomide of particles of the ceramics.
The first type includes nanosized particles (particles I); the particles, the radius of which is about 100 nm, are related to the second type (particles II). The third type is the particles of micron size (particles III). Aggregates of particles I and II are located on the surface of particles III. Figure 4b,c,d shows TEM images of powder of the modified membrane. The aggregates of HZD particles (several hundreds nanometers, particles III), which were shaded by organic acid, are visible on the surface of micron particles of ceramics (grey clouds), as seen in Figure 4b. These aggregates include smaller ones, the size of which is about 100 nm (particles II) (Figure 4c,d). At last, these aggregates consist of nanoparticles (particles I). Their shape is close to spherical but distorted, opposite to the sol constituent due to thermal treatment of the composite membrane. Figure 3 SEM image of transverse section of initial (a) and modified (b) membranes. Particles of ceramics, the shape of which is close to spherical, are visible (a), and aggregates of HZD particles are seen inside pores of the matrix (b).