Often we encounter metal powders both in a life, and in industrial activity.
Usually we deal with powders which have sizes of particles tens or hundreds micron. Basically powders with particles in size more than 10 microns are used even in powder metallurgy. A human eye can see a point in 20 micron. The powders can have absolutely new characteristics.
Particles which have size from 1 to 100 nano meters usually identify like «nanoparticles». The area of nano sizes is transitional between amorphous and crystalline state of substances. In this area structured characteristics begin to play an important role in addition to size factor.
The change of fundamental characteristics of traditional materials in nano disperse condition (decrease: thaw point, heat of evaporation, ionization energy, electronic work function, etc.) discovers the broadest possibilities in the field of creation of the newest materials and technologies, conceptually new devices and instruments.
Nano particles of some materials have very good catalytic and adsorptive properties. Other materials show us surprising optical properties, for example, super thin films of organic materials which can be applied to production of flexible solar batteries.
One can share nano particles on 3 basic classes:
3-dimensional particles – particles received by explosion of conductors, plasma synthesis, restoration of thin films etc.;
2-dimensional objects— the films received by methods molecular layering, a method ionic layering etc.;
1-dimensional objects — nano fibers
Nano composites — the materials received by injection of nano particles into any matrixes.
Nano materials – the materials, which has structured fragments from 1 to 100 nanometers.

Our technological
process.

In a basis of our technology the phenomenon of wire electrical explosion (WEE) is necessary. Through a piece of metal wire (foil) impulse of current is put through and under its influence the wire bursts into finest particles and stream. When scattered at great speed, products of destruction quickly cool down and form nanosized powders (NP). Technological process is carried out in isolated spaces, without use of harmful chemical substances and with small expenditure of inert gases. Besides, gas expenditure is mainly connected not with powder production, but with its transportation, packing and other further operations. Depending on the sort of gas, surrounding the destroyed wire, it’s possible to receive powders of metals, alloys, powders of chemical combinations or compositional structures. Thus, separate particles are composite.
Characteristics of our powders.
Dispersion of a powder, structure (architecture) of particles and other characteristics are defined by parameters of a digit contour, a material and the geometrical sizes of a wire (foil) and characteristics of the gas environment in which explosion is made. Size distributions of the particles received by electro explosive technology, tend to submit to a logarithmic variant of the normal law of distribution. All a particle, received on our technology, have the spherical form. In certain cases particles with poorly expressed facet can be formed. As the process of formation of particles occurs in no equilibrium conditions, a structural and phase heterogeneity (polymorphism) become its’ characteristics. Powder particles are formed from the incoherently-packed blocks (structural fragments) in the size range from 20 to 40 nanometers.
The crystal lattice of blocks is deformed in no small degree. Some quantity of metal is in disorder (a X-ray - amorphous) condition that allows to carry considered object to the systems which structure is intermediate, between crystal and amorphous. At heating of such structure to certain temperature (sometimes temperature is only 40 – 50○С) the process of crystallization accompanied by
allocation of free energy begins.

The basic characteristics which distinguish electro explosive powders from others:
- Very low temperatures of sintering. The silver powder conglomerates at temperature
nearby 70°С;
- Stability of electrophysical properties in the field of low temperatures;
- High chemical activity. At achievement of threshold temperatures (200-500) °С chemical activity increases repeatedly;
- High value of factor of absorption of electromagnetic radiation in a wide range of
frequencies.
- The lowered work of an exit of electrons;
- Presence of the superfluous (reserved) energy.
Areas of possible applications of our production or where to search for consumers:
1. Small additives of nano powders raise characteristics of heavy-duty high density materials, for example (W-Ni-Fe);
special composite materials, for example (magnetic - Nd-Fe-B, superconductors -
Ba-Cu-O, Ba-Fe-O); improve mechanical characteristics of rubbers and polymers.
2. Electroconductive polymers, pastes, paints.
3. Gas absorbers and cathodes of gas-discharge lamps.
4. Alkali metal grease. Additives to oils. Materials with extremely low factor of a friction (WS2, MoS2);
5. Manufacture of technical corundum (polishing pastes, semiprecious stones).
6. Cluster and magnetic liquids. Cooling liquids.
7. Nano in technologies of water purification, water solutions, other liquids and gases. Filtering materials based on nano-fibers. Modification
of filtering materials and membranes.
8. Nano in medicine: drug delivery; new medical products based on nano particles as anticancer therapy; healing of burns and
wounds.
9. Sprayed cathodes and electro-contacting materials.
10. Components of solders with low temperature of the soldering and a high temperature of unsoldering for connection of diverse
materials (glass – metal; the semiconductor – metal; jewels – metal, etc.).
11. Nano particles of many materials (for example, silver) possess strong disinfecting effect. Release of materials, paints,
varnishes, the coverings possessing disinfecting characteristics, is necessary
for the food production, medicine, agriculture and other industries.
12. Composite pastes for laying of functional metal layers on various products, for example, solar energy converters.
13. Components of fuel, pyrotechnic structures and explosives.
14. Heat-producing elements and hydrogen generators and other gases.



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Welcome! Nanopaprika was cooked up by Hungarian chemistry PhD student in 2007. The main idea was to create something more personal than the other nano networks already on the Internet. Community is open to everyone from post-doctorial researchers and professors to students everywhere.

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Dr. András Paszternák, founder of Nanopaprika

Publications by A. Paszternák:

Pd/Ni Synergestic Activity for Hydrogen Oxidation Reaction in Alkaline Conditions

The potential use of cellophane test strips for the quick determination of food colours

pH and CO2 Sensing by Curcumin-Coloured Cellophane Test Strip

Polymeric Honeycombs Decorated by Nickel Nanoparticles

Directed Deposition of Nickel Nanoparticles Using Self-Assembled Organic Template,

Organometallic deposition of ultrasmooth nanoscale Ni film,

Zigzag-shaped nickel nanowires via organometallic template-free route

Surface analytical characterization of passive iron surface modified by alkyl-phosphonic acid layers

Atomic Force Microscopy Studies of Alkyl-Phosphonate SAMs on Mica

Amorphous iron formation due to low energy heavy ion implantation in evaporated 57Fe thin films

Surface modification of passive iron by alkylphosphonic acid layers

Formation and structure of alkylphosphonic acid layers on passive iron

Structure of the nonionic surfactant triethoxy monooctylether C8E3 adsorbed at the free water surface, as seen from surface tension measurements and Monte Carlo simulations

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