Colorants, characterization precursors

Cowen, J. E. Riga, A. T. Hepp, A. F. Duraj, S. A. Banger, K. K. McClarnon, R. 2004. Synthesis and characterization of CuInS2 single source precursors for chemical vapor deposition. J. Therm. Analysis and Color. 75 929-936. 

Another nice example of nanostructuring an MIP layer is the work published by Wu et al. [138, 139] who developed a label-free optical sensor based on molecularly imprinted photonic polymers. Photonic crystals were prepared by self-assembly of silica nanospheres. The space between the spheres was then filled with MIP precursor solution. After polymerization, the silica was dissolved, leaving an MIP in the form of a 3D-ordered interconnected macroporous inverse polymer opal (Fig. 15). The authors were able to detect traces of the herbicide atrazine at low concentrations in aqueous solution [139]. Analyte adsorption into the binding sites resulted in a change in Bragg diffraction of the polymer characterized by a color modification (Fig. 15). 

The porphyrias are a group of disorders caused by abnormalities in heme biosynthesis. They are inherited and acquired disorders characterized by excessive accumulation and excretion of porphyrins or their precursors. Defects in any one of the eight enzymes involved in heme biosynthesis may cause inherited porphyrin-related disorders (Figure 29-9). Porphyrins have a deep red or purple color (Greek porphyra = purple). Porphyrins are... 

In addition to titration methods, the solutions have been characterized on the basis of the composition of the precursor alloys, color, and occasionally by NMR methods (Table 4). The structures of mixed-cluster anions of group-14 elements are only poorly characterized. °° ° Mixed anions such as Sn Pbg j," " (0 <. Y < 9) can be synthesized electrochemically by using a 1 1 Sn/Pb alloy as the cathode. All nine-atom clusters are fluxional in solution. 

When the films were exposed to H2S gas, the colored and transparent conducting films were form. Energy dispersive X-ray spectroscopy(EDX) examination showed that the molar ratio of Cu/S was from 1.1 to 1.3, indicating the formation of CuS. The particles precipitated in the films wae characterized with TEM observation. The particle size, size distribution and composite structure of the films were influenced by the precursor film composition. Figure 3 shows the TEM images from the CuS particles dispersed HPC films without addition of silica sol and AICI3. 

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