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A thermo-chemical nanoparticle generator for the controlled production of nanoparticles, and a method of controllably producing nanoparticles are provided. The combustion of a carbon based propellant under the controlled variation of combustion parameters (temperature, pressure and stoichiometry) al

A thermo-chemical nanoparticle generator for the controlled production of nanoparticles, and a method of controllably producing nanoparticles are provided. The combustion of a carbon based propellant under the controlled variation of combustion parameters (temperature, pressure and stoichiometry) allows for the production of ionized nanoparticles of a defined mass. In addition, with the assistance of a high voltage generator a combined ionized gas-/solid particle plasma stream can be produced, which can accelerated in an acceleration tube to high emission velocities allowing for applications of the invention ranging from spacecraft propulsion to plasma welding.

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The invention claimed is: 1. A particle generator comprising: a fuel source for supplying a combustible fuel; an oxidizer source for supplying an oxidizer; at least one combustion chamber having first and second ends; an exhaust port being disposed at the second end of each of said at least one com

The invention claimed is: 1. A particle generator comprising: a fuel source for supplying a combustible fuel; an oxidizer source for supplying an oxidizer; at least one combustion chamber having first and second ends; an exhaust port being disposed at the second end of each of said at least one combustion chamber; and at least one combustion source disposed within each of said combustion chambers at a first end thereof, in fluid communication with said fuel source and said oxidizer source, where said combustion source supports stable flame combustion of said fuel at an air demand ratio (λ) is λ>0.5; at least one tunable high voltage generator for applying a positive voltage to walls of the combustion chamber to extract electrons out of the flame and promote the formation of particles, such that an exhaust of particles is generated; where the temperature and air demand ratio of the combustion source, the retention time of the exhaust within the combustion chamber, and/or the applied positive voltage are varied to control the mass of the particles output from said particle generator. 2. A particle generator comprising: a fuel source for supplying a combustible fuel; an oxidizer source for supplying an oxidizer; at least one combustion chamber having first and second ends; an exhaust port being disposed at the second end of each of said at least one combustion chamber; at least one combustion source disposed within each of said combustion chambers at a first end thereof, in fluid communication with said fuel source and said oxidizer source, where said combustion source supports stable flame combustion of said fuel in the domain where an air demand ratio (λ) is λ>0.5 such that an exhaust of particles is generated, and where the temperature and air demand ratio of the combustion source and the retention time of the exhaust within the combustion chamber are varied to control the mass of the particles output from said particle generator; and a secondary fuel source in fluid communication with said combustion chamber, wherein the secondary fuel source is disposed to deliver a pyrolysis fuel comprising at least one high molecular mass hydrocarbon into the exhaust of particles generated by the burner. 3. The particle generator described in claim 2, wherein the pyrolysis fuel is gasoline, diesel or fuel oil. 4. The particle generator described in claim 1, wherein the temperature of the combustion may be varied from around 1000 K to around 2500 K. 5. The particle generator described in claim 1, wherein the air demand ratio λ is within a range of around 0.5 to around 1.0. 6. The particle generator described in claim 1, wherein the at least one combustion source is a burner selected from the group consisting of swirl, diffusion plate, and partially premixed. 7. The particle generator described in claim 6, wherein the at least one combustion source is a swirl burner having a configuration selected from the group consisting of turbulent diffusion and stabilized pressure plate-diffusion. 8. The particle generator described in claim 1, comprising at least two combustion sources disposed within a single combustion chamber. 9. The particle generator described in claim 8, wherein the at least two combustion sources are disposed in an arrangement selected from the group consisting of centric, circular or planar. 10. The particle generator described in claim 1, wherein the fuel from the fuel source is introduced into said combustion chamber via an atomizer. 11. The particle generator described in claim 1, wherein the oxidizer is introduced into said combustion chamber via an air blast nozzle. 12. A particle generator comprising: a fuel source for supplying a combustible fuel; an oxidizer source for supplying an oxidizer, at least one combustion chamber having first and second ends, wherein the oxidizer is introduced into said combustion chamber via an air blast nozzle, and the air blast nozzle is disposed such that it causes the fuel to be swirled within said combustion chamber; an exhaust port being disposed at the second end of each of said at least one combustion chamber; and at least one combustion source disposed within each of said combustion chambers at a first end thereof, in fluid communication with said fuel source and said oxidizer source, where said combustion source supports stable flame combustion of said fuel in the domain where an air demand ratio (λ) is λ>0.5 such that an exhaust of particles is generated, and where the temperature and air demand ratio of the combustion source and the retention time of the exhaust within the combustion chamber are varied to control the mass of the particles output from said particle generator. 13. A particle generator comprising: a fuel source for supplying a combustible fuel; an oxidizer source for supplying an oxidizer; at least one combustion chamber having first and second ends; an exhaust port being disposed at the second end of each of said at least one combustion chamber; at least one combustion source disposed within each of said combustion chambers at a first end thereof, in fluid communication with said fuel source and said oxidizer source, where said combustion source supports stable flame combustion of said fuel in the domain where an air demand ratio (λ) is λ>0.5 such that an exhaust of particles is generated, and where the temperature and air demand ratio of the combustion source and the retention time of the exhaust within the combustion chamber are varied to control the mass of the particles output from said particle generator; and at least one accelerator itself comprising an elongated channel having first and second ends, wherein the first end of the accelerator is in fluid communication with the exhaust port of the combustion chamber, and wherein the accelerator has a variable electric field applied thereto such that ionized particles entering the first end of the accelerator are accelerated therefrom via the variable electric field. 14. The particle generator described in claim 13, wherein the electric field is generated by a tunable high voltage generator. 15. The particle generator described in claim 13, wherein the accelerator is equipped with at least one magnet concentrically arranged around said elongated channel, said at least one magnet being selected from the group of permanent magnets or electromagnets. 16. The particle generator described in claim 13, wherein the length and diameter of the elongated channel is variable. 17. The particle generator described in claim 16, wherein the elongated channel of the accelerator is formed of several concentric cylinders, which can be telescopically moved with respect to each other to vary the length and diameter of the elongated channel. 18. The particle generator described in claim 13, wherein the accelerator is made of a material selected from an electrically conducting high temperature material. 19. The particle generator described in claim 18, wherein the material is selected from the group consisting of steel and tungsten. 20. The particle generator described in claim 13, wherein the accelerator is coated with a dielectric material. 21. The particle generator described in claim 13, wherein the accelerator is made of at least two segments that are separated by means of electrical insulators. 22. The particle generator described in claim 13, wherein the at least two segments are powered by different high voltage generators. 23. The particle generator described in claim 13, further comprising at least one passive or active electron emitter disposed at the second end of the accelerator. 24. A particle generator comprising: a fuel source for supplying a combustible fuel: an oxidizer source for supplying an oxidizer: at least one combustion chamber having first and second ends: an exhaust port being disposed at the second end of each of said at least one combustion chamber; at least one combustion source disposed within each of said combustion chambers at a first end thereof, in fluid communication with said fuel source and said oxidizer source, where said combustion source supports stable flame combustion of said fuel in the domain where an air demand ratio (λ) is λ>0.5 such that an exhaust of particles is generated, and where the temperature and air demand ratio of the combustion source and the retention time of the exhaust within the combustion chamber are varied to control the mass of the particles output from said particle generator; and a wall gas source in fluid communication with said combustion chamber, said wall gas being injected into said combustion chamber by at least one injector designed to flow said wall gas along the walls of said combustion chamber. 25. The particle generator described in claim 24, wherein the at least one injector is selected from the group consisting of slits, (nanoscopic, or microscopic holes), splits or tubes. 26. The particle generator described in claim 24, wherein the at least one combustion chamber is designed in the shape of several concentric cylinders, such that the wall gas is guided from the wall gas source through the interstice between the cylinders through the at least one injector into the combustion chamber. 27. The particle generator described in claim 24, wherein the wall gas is selected from the group consisting of hydrogen (H2), methane (CH4) or another hydrocarbon of the formula CxHy, nitrogen (N2) or a noble gas. 28. A particle generator comprising: a fuel source for supplying a combustible fuel; an oxidizer source for suppling an oxidizer; at least one combustion chamber having first and second ends; an exhaust port being disposed at the second end of each of said at least one combustion chamber; at least one combustion source disposed within each of said combustion chambers at a first end thereof, in fluid communication with said fuel source and said oxidizer source, where said combustion source supports stable flame combustion of said fuel in the domain where an air demand ratio (λ) is λ>0.5 such that an exhaust of particles is generated, and where the temperature and air demand ratio of the combustion source and the retention time of the exhaust within the combustion chamber are varied to control the mass of the particles output from said particle generator; and a particle ionizer capable of applying an ionizing energy to the particles in the combustion chamber selected from the group consisting of an electron bombardment source, a microwave source, a ultraviolet source, or an HF-inductor. 29. The particle generator described in claim 13, further comprising a particle ionizer capable of applying an ionizing energy to the nanoparticles in the accelerator selected from the group consisting of an electron bombardment source, a microwave source, a ultraviolet source, or an HF-inductor. 30. The particle generator described in claim 23, further comprising a diffuser disposed at the second end of the accelerator; and wherein the angle of the particle exhaust and the electron emission are parallel such that the electrons and the particles recombine behind the generator. 31. The particle generator described in claim 30, wherein the particle generator is designed for use as a propulsion source within a spacecraft. 32. The particle generator described in claim 23, wherein the second end of the accelerator is formed as a cylinder, and wherein the angle between the particle exhaust and the electron emission may be varied to allow the recombination of the electrons and the particles to be focused at a single point. 33. The particle generator described in claim 32, wherein the particle generator is designed for use as a plasma welder. 34. The particle generator described in claim 23, further comprising a recombination chamber disposed at the second end of the accelerator; a tertiary gas inlet in fluid communication with said recombination chamber; and an oxygen source in fluid communication with said recombination chamber, wherein the electrons and the particles recombine within the recombination chamber thereby heating the mixture of the tertiary gas and oxygen within the chamber. 35. The particle generator described in claim 34, wherein the particle generator is designed for use as a plasma torch for incinerating pollutants or other solid wastes. 36. A particle generator comprising: a fuel source for supplying a combustible fuel; an oxidizer source for supplying an oxidizer; at least one combustion chamber having first and second ends; an exhaust port being disposed at the second end of each of said at least one combustion chamber; at least one combustion source disposed within each of said combustion chambers at a first end thereof, in fluid communication with said fuel source and said oxidizer source, wherein said combustion source supports stable flame combustion of said fuel in the domain where an air demand ratio (λ) is λ>0.5 such that an exhaust of particles is generated, wherein the temperature and air demand ratio of the combustion source and the retention time of the exhaust within the combustion chamber are varied to control the mass of the particles output from said particle generator, and wherein a heavy metal is disposed within the combustion chamber such that the heavy metal evaporates during combustion. 37. The particle generator described in claim 36, wherein the heavy metal is incorporated into the walls of the combustion chamber. 38. The particle generator described in claim 36, wherein the heavy metal is selected from the group of a main group metal, a d-block metal, a main group f-block metal, or an alloy thereof. 39. A particle generator comprising: a fuel source for supplying a combustible fuel; an oxidizer source for supplying an oxidizer; at least one combustion chamber having first and second ends; an exhaust port being disposed at the second end of each of said at least one combustion chamber; at least one combustion source disposed within each of said combustion chambers at a first end thereof, in fluid communication with said fuel source and said oxidizer source, wherein said combustion source supports stable flame combustion of said fuel in the domain where an air demand ratio (λ) is λ>0.5 such that an exhaust of particles is generated, wherein the temperature and air demand ratio of the combustion source and the retention time of the exhaust within the combustion chamber are varied to control the mass of the particles output from said particle generator; and a heavy metal source in fluid communication with said combustion chamber for introducing a heavy metal containing vapor thereto during combustion. 40. The particle generator described in claim 39, wherein the heavy metal is selected from the group of a main group metal, a d-block metal, a main group f-block metal, or an alloy thereof. 41. A method of controllably forming particles comprising the steps of: introducing a fuel and an oxidizer at an air demand ratio of around λ>0.5 in a combustion chamber; combusting the fuel and oxidizer in the combustion chamber at a temperature from around 1000 K to around 2500 K for a retention time of at least one millisecond; and applying an electric potential to extract electrons; and varying the temperature, the air demand ratio, the electric potential, and/or the retention time to produce an exhaust comprising particles having a controlled mass. 42. A method of controllably forming particles comprising: introducing a fuel and an oxidizer at an air demand ratio of around λ>0.5 in a combustion chamber; combusting the fuel and oxidizer in the combustion chamber at a temperature from around 1000 K to around 2500 K for a retention time of at least one millisecond; varying the temperature, the air demand ratio and the retention time to produce an exhaust comprising particles having a controlled mass, wherein the step of combusting uses a stabilized diffusion flame burner. 43. The method described in claim 41, wherein the step of combusting uses a swirl flame burner. 44. The method described in claim 41, further comprising the step of: introducing a "wall-gas" into the combustion chamber to protect the walls of the combustion chamber. 45. A method of controllably forming particles comprising: introducing a fuel and an oxidizer at an air demand ratio of around λ>0.5 in a combustion chamber; combusting the fuel and oxidizer in the combustion chamber at a temperature from around 1000 K to around 2500 K for a retention time of at least one millisecond; varying the temperature, the air demand ratio and the retention time to produce an exhaust comprising particles having a controlled mass; and applying an electrical field to accelerated ionized particles. 46. A method of controllably forming particles comprising: introducing a fuel and an oxidizer at an air demand ratio of around λ>0.5 in a combustion chamber; combusting the fuel and oxidizer in the combustion chamber at a temperature from around 1000 K to around 2500 K for a retention time of at least one millisecond; varying the temperature, the air demand ratio and the retention time to produce an exhaust comprising particles having a controlled mass; and introducing a second high molecular weight fuel to the combustion. 47. A method of controllably forming particles comprising: introducing a fuel and an oxidizer at an air demand ratio of around λ>0.5 in a combustion chamber; combusting the fuel and oxidizer in the combustion chamber at a temperature from around 1000 K to around 2500 K for a retention time of at least one millisecond; varying the temperature, the air demand ratio and the retention time to produce an exhaust comprising particles having a controlled mass; and bombarding ionized particles with a stream of electrons to neutralize the particles. 48. A method of controllably forming particles comprising: introducing a fuel and an oxidizer at an air demand ratio of around λ>0.5 in a combustion chamber; combusting the fuel and oxidizer in the combustion chamber at a temperature from around 1000 K to around 2500 K for a retention time of at least one millisecond; varying the temperature, the air demand ratio and the retention time to produce an exhaust comprising particles having a controlled mass; and introducing a heavy metal into the combustion. 49. The method described in claim 48, wherein the heavy metal is selected from the group consisting of a main group metal, a d-block metal, a main group f-block metal, or an alloy thereof.