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1. Colloidal particles On this subject the following basic results are received: It is established, that colloidal particles of silver with the size less.

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Presentation on theme: "1. Colloidal particles On this subject the following basic results are received: It is established, that colloidal particles of silver with the size less."— Presentation transcript:

1 1. Colloidal particles On this subject the following basic results are received: It is established, that colloidal particles of silver with the size less than 3 nm in a diameter have no metallic properties, silver becomes dielectric. Produced a lot of colloidal particles with various size distribution from Au, Ag, Fe x O y, AgHal, silver insoluble salts like Ag 4 [Fe(CN) 6 ], Ni 2 [Fe(CN) 6 ], PbAg 2 [Fe(CN) 6 ], Cd 2 [Fe(CN) 6 ], Fe 4 [Fe(CN) 6 ] 3, Cu 2 [Fe(CN) 6 ], Co 2 [Fe(CN) 6 ], PbCrO 4, Ag 2 S, Ag 2 Se, (UO 2 ) 2 [Fe(CN) 6 ], a.a. in various media : water, gel, polymers, alcohol a.a. The spectral and granulometric properties, stability, surface tension, oxidizing, reduction of colloidal particles were investigated. The optical constants of small silver particles are strongly differ from properties of massive silver. The value of a surface tension of silver for small colloidal particles and clusters is determined as 860 mJ/m 2. The topography of biologically active components on cells surface was investigated by colloidal particles of noble metals as markers. The original electron microscopic method of replica preparation from cell surface without cells surfaces’ damage was developed. It was used the colloidal magnetic particles (beads) for detection of individual interactions between components of immunochemical reaction (so-called, BARC format “Beads-ARray- Counter”). It has offered the using of small magnetic colloidal particles as detecting elements, which can be produced by ultrasonic method of metals carbonyls destruction such as Fe(CO) 6 and Ni(CO) 4. Development of the methods of protection of such small particles of metal from oxidation in water solutions with the help of gold coating or polymers films. The alternative opportunity is considered to use magnetic stable particles based on metals oxides.

2 2. Monomolecular (Langmuir) films On this subject the following results are received: The films of proteins, enzymes, receptors and polymers, the recipes of polymeric structures are received which are capable to protect biologically active substances from inactivation on air and on border of phases by formation of special protein-polymeric compositions, are used as negatively charged polyelectrolites (like poly-laurilacrylate), and positively charged ones (like poly-4-vinil-pyridine, cethyl radical modified poly- ethylenimine). It was shown, that the properties adsorbed enzymes on a solid surface are essentially different depending on that in what condition they are - adsorbed by a usual way which is taken over in immunochemistry, or as the 2D molecular Langmuir films. In the latter case enzymes are more active (the constants of enzymatic processes are differ). It was found that the films from fatty acids can be use as dielectric layer for structures such as “metal-barrier-metal" (Al-[Langmuir films of C 17 H 35 COOH]-Ag, Ag-Al 2 O 3 -Ag, Ag-SiO 2 -Ag, Ag-HfO 2 -Ag), which are used in optoelectronics. Langmuir layers of platinum-phtalocyanine dyes are investigated and it is established, that they can be used for creation of fiber-optic sensors of water vapors in air and oxygen and liquid phases.

3 3. Formation of new impurity phase in microcrystals (systems) with small volume On this subject the following results are received: The rules of formation of photolytic arising new phase of silver in ultra-fine-grain Lippmann photo-emulsions are investigated, with the help of chemical thermodynamics the interrelation between the sizes of arising colloidal particles of silver, size of AgBr micro-crystals, where they are formed, and size of formed oligoatomic silver clusters is shown. It was shown, that in small volume thermodynamic systems alongside with the formed new phase in equilibrium should be oligoatomic clusters of admixture. Cluster concentration, size of particles and the volume of new phase, in which they are formed, are interdependent. The processes of formation of a new impurity phase based on electron microscopic level are investigated as in ultra pure crystals of KCl, ZnO etc as in crystals with the specially entered impurity of ions Cd 2+, Pb 2+, Sn 2+, OH - etc. The linear dependence between the size of pre- precipitation area and the size of formed new phase is established. The investigation of spectrozonal redeposition process of silver in photo-emulsions is carried out. It is established, that the basic role in the given process play small colloidal particles of silver with the diameter 3-6 nm and band of absorption at 430-460 nm.

4 Classification of clusters and colloidal particles


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