Abstract: A compact, simpler, more economical ICF target chamber and reactor design that maintains a low internal pressure, sub-atmospheric, and very small neutron flux on any pressure bearing vessel or steam generating mechanism. The present invention reduces radiant target emission towards the nearest wall of the hohlraum wall and/or sleeve material so that the radiation from target burn exits the end of the hohlraum through a wall material sufficiently thick to contain the target drive radiation, but becomes transparent to the target emitted radiation. The compact converter contains the energy released by the ICF target and converts it into usable heat to create steam. It also converts the excess neutrons, from the ICF target, into tritium. This is then collected with the unburnt fuel tritium.

Abstract: A novel thin-film target can the life of tritium targets for the production of 14 MeV neutrons by the 3H(2H,n)4He nuclear reaction while using only a small fraction of the amount of tritium compared to a standard thick-film target. With the thin-film target, the incident deuterium is implanted through the front tritide film into the underlying substrate material. A thin permeation barrier layer between the tritide film and substrate reduces the rate of tritium loss from the tritide film. As an example, good thin-film target performance was achieved using W and Fe for the barrier and substrate materials, respectively.

Abstract: An electrolytic method of loading hydrogen into a cathode includes placing the cathode and an anode in an electrochemical reaction vessel filled with a solvent, mixing a DC component and an AC component to produce an electrolytic current, and applying an electrolytic current to the cathode. The DC component includes cycling between: a first voltage applied to the cathode for a first period of time, a second voltage applied to the cathode for a second period of time, wherein the second voltage is higher than the first voltage, and wherein the second period of time is shorter than the first period of time. The peak sum of the voltages supplied by the DC component and AC component is higher than the dissociation voltage of the solvent. The AC component is selected based on a local minimum of a Nyquist plot to minimize energy loss while maintaining hydrogen transport.

Abstract: A target system for irradiation of molybdenum with charged particles from an accelerator to produce technetium and molybdenum radioisotopes. The target system comprises a molybdenum-100 material brazed with a brazing alloy to a backing material. The backing material preferably comprises a dispersion-strengthened copper composite. The brazing alloy comprises copper and phosphorus.

Abstract: According to one embodiment, a method for producing a directed neutron beam includes producing a voltage of negative polarity of at least ?100 keV on a surface of a deuterated or tritiated target in response to a temperature change of a pyroelectric crystal of less than about 40° C., the pyroelectric crystal having the deuterated or tritiated target coupled thereto, pulsing a deuterium ion source to produce a deuterium ion beam, accelerating the deuterium ion beam to the deuterated or tritiated target to produce a neutron beam, and directing the ion beam onto the deuterated or tritiated target to make neutrons using at least one of a voltage of the pyroelectric crystal, and a high gradient insulator (HGI) surrounding the pyroelectric crystal. The directionality of the neutron beam is controlled by changing the accelerating voltage of the system. Other methods are presented as well.

Abstract: A portable neutron generator is provided that does not utilize liquid cooling. The portable neutron generator includes a vacuum chamber housing defining a vacuum chamber and an ion beam inlet. The portable neutron generator also includes a rotating target positioned within the vacuum chamber. The ion beam inlet is oriented to receive ions such that the ions impinge upon the rotating target to cause neutrons to be emitted. The rotating target comprises a copper alloy. The portable neutron generator also includes a motor core positioned within the vacuum chamber and coupled to the rotating target. A motor stator is electromagnetically coupled with the motor core. The motor core is configured to rotate the rotating target at greater than 200 Hz during operation.

Abstract: The disclosed embodiments include downhole neutron generators and methods to utilize downhole neutron generators in a downhole environment. In one embodiment, a downhole neutron generator includes a heating element to dissipate heat to a first transition metal, which heats up the first transition metal and facilitates the first transition metal to absorb deuterium and tritium gases flowing proximate said transition metal. The downhole neutron generator also includes a second transition metal separated from the target foil, where the second transition metal is doped with of deuterium and the tritium ions, and a laser to direct optical pulses onto a surface of the first transition metal to produce deuterium and the tritium ions from the absorbed deuterium and tritium, where said ions traverse through a back surface of the first transition metal to the second transition metal to interact with the doped deuterium and the tritium ions to initiate fusion reaction.

Abstract: Abeam shaping assembly for neutron capture therapy includes a beam inlet, a target having nuclear reaction with an incident proton beam from the beam inlet to produce neutrons forming a neutron beam defining a main axis, a moderator adjoining to the target, a reflector surrounding the moderator, a thermal neutron absorber adjoining to the moderator, a radiation shield arranged inside the beam shaping assembly and a beam outlet. The neutrons are moderated to epithermal neutron energies. The reflector leads the neutrons deviated from the main axis back, and a gap channel is arranged between the moderator and the reflector. The thermal neutron absorber is used for absorbing thermal neutrons so as to avoid overdosing in superficial normal tissue during therapy. The radiation shield is used for shielding leaking neutrons and photons so as to reduce dose of the normal tissue not exposed to irradiation.

Abstract: Design and making methods of a neutrons generating target are described. In some embodiments, a surface of a target substrate can be modified to form one or more surface features. In some embodiments, a neutron source layer can be disposed on the surface of the target substrate. In some embodiments, the neutron source layer and the target substrate can be heated to an elevated temperature to form a bond between the two. In some embodiments, the surface modification of the target substrate can reduce blistering and material exfoliation in the target. The target can be used in boron neutron capture therapy.

Abstract: A beam shaping assembly for neutron capture therapy includes a beam inlet, a target having nuclear reaction with an incident proton beam from the beam inlet to produce neutrons forming a neutron beam defining a main axis, a moderator adjoining to the target, a reflector surrounding the moderator, a thermal neutron absorber adjoining to the moderator, a radiation shield arranged inside the beam shaping assembly and a beam outlet. The neutrons are moderated to epithermal neutron energies. The reflector leads the neutrons deviated from the main axis back, and a gap channel is arranged between the moderator and the reflector. The thermal neutron absorber is used for absorbing thermal neutrons so as to avoid overdosing in superficial normal tissue during therapy. The radiation shield is used for shielding leaking neutrons and photons so as to reduce dose of the normal tissue not exposed to irradiation.

Abstract: According to one embodiment, an apparatus includes a pyroelectric crystal, a deuterated or tritiated target, an ion source, and a common support coupled to the pyroelectric crystal, the deuterated or tritiated target, and the ion source. In another embodiment, a method includes producing a voltage of negative polarity on a surface of a deuterated or tritiated target in response to a temperature change of a pyroelectric crystal, pulsing a deuterium ion source to produce a deuterium ion beam, accelerating the deuterium ion beam to the deuterated or tritiated target to produce a neutron beam, and directing the ion beam onto the deuterated or tritiated target to make neutrons using a voltage of the pyroelectric crystal and/or an HGI surrounding the pyroelectric crystal. The directionality of the neutron beam is controlled by changing the accelerating voltage of the system. Other apparatuses and methods are presented as well.

Abstract: A method of impacting liquid droplets onto a surface includes providing a series of liquid droplets, and directing the liquid droplets at a non-planar target surface to cause a shockwave in the droplets upon impact. An apparatus for impacting liquid droplets onto a surface includes a mechanism to produce a series of liquid droplets, and a mechanism to direct the liquid droplets at a non-planar target surface to cause a shockwave in the droplets upon impact. The non-planar target surface is shaped to intensify the shockwave in the droplets.

Abstract: An object is to be capable of inducing a nuclear fusion reaction at a relatively high efficiency and downsize a device. A nuclear fusion device 1 of the present invention includes a nuclear fusion target 7 including a target substrate 7a containing deuterium or tritium and a thin-film layer 7b containing deuterium or tritium stacked on the target substrate 7a, a vacuum container 5 for storing the nuclear fusion target 7, and a laser unit 3 for irradiating two successive first and second pulsed laser lights P1, P2 toward the thin-film layer 7b of the nuclear fusion target 7, and the intensity of the first pulsed laser light P1 is set to a value that is smaller than that of the second pulsed laser light P2 and allows peeling of the thin-film layer 7b from the target substrate 7a.

Abstract: Disclosed herein is a high current solid target for radioisotope production at a cyclotron using a metal foam, and more specifically, a high current solid target for isotope production, which attaches a metal foam to the rear surface of the solid target plate. A high current solid target for isotope production including a metal foam according to the present invention may exhibit excellent cooling performances to increase the amount of proton beam current irradiated on the solid target compared to conventional planar-type solid targets. Because the irradiation of the increased proton beam current may increase the amount of an isotope produced per unit time and even an irradiation of proton beam in a short time may allow for production of a desired amount of an isotope, the solid target may be usefully used for production of medical cyclotron nuclides.

Abstract: In accordance with embodiments disclosed herein, there are provided systems, apparatuses and methods for the implementation of an energy system. A mechanical fusion energy system using uniquely constructed fuel pellets containing a variety of fusion capable materials to achieve up to many Megawatts of relatively continuous power output. The disclosed energy system utilizes a quantum approach of individual discrete pops periodically as needed to maintain a fairly continuous flow of energy. It may generate several thousand KWhr of energy per pop and dependent on the pop rate may generate well over 1,000 Megawatts, equivalent to the largest power generating stations currently in operation.

Abstract: A fusion fuel capsule is disclosed having a substantially spherical ablator shell. The interior surface of the shell is lined with a nanoporous scaffold layer wetted with either a fully or partially liquid mixture of deuterium and tritium.

Abstract: A target is provided herein such that the radioactivation of a member thereof due to protons may be reduced. In order to reduce the radioactivation of the member due to protons, a novel target composed by compositing a beryllium material (or lithium material) and a nonmetal material is used.

Abstract: A composition suitable for use as a target containing antimony to be irradiated by accelerated charged particles (e.g., by protons to produce tin-117m) comprises an intermetallic compound of antimony and titanium which is synthesized at high-temperature, for example, in an arc furnace. The formed material is powdered and melted in an induction furnace, or heated at high gas pressure in gas static camera. The obtained product has a density, temperature stability, and heat conductivity sufficient to provide an appropriate target material.

Abstract: Provided are a method and apparatus for low energy nuclear reactions in hydrogen-loaded metals. A nickel cathode is disposed inside a pressure vessel loaded with heavy water. The vessel is heated to a temperature at which nickel oxide is reduced in the presence of hydrogen. The cathode is electrified, thereby producing hydrogen at the cathode, which removes any oxide layer on the nickel. The nickel can therefore more easily be loaded with hydrogen. The nickel cathode preferably has embedded particles of neutron-absorbing and/or hydrogen absorbing materials, such as boron-10, lithium-containing compounds, palladium, niobium, vanadium, or other hydrogen storage intermetallic compounds, alloys, or amorphous alloys.

Abstract: Fuel pellets for use as targets in thermonuclear fusion by inertial confinement are manufactured from a solid palladium core that contains deuterium tritium gases. The palladium core is covered with a tamper-ablator shell of heavy metal selected from the group including gold, platinum, and tungsten.

Abstract: An object is to be capable of inducing a nuclear fusion reaction at a relatively high efficiency and downsize a device. A nuclear fusion device 1 of the present invention includes a nuclear fusion target 7 including a target substrate 7a containing deuterium or tritium and a thin-film layer 7b containing deuterium or tritium stacked on the target substrate 7a, a vacuum container 5 for storing the nuclear fusion target 7, and a laser unit 3 for irradiating two successive first and second pulsed laser lights P1, P2 toward the thin-film layer 7b of the nuclear fusion target 7, and the intensity of the first pulsed laser light P1 is set to a value that is smaller than that of the second pulsed laser light P2 and allows peeling of the thin-film layer 7b from the target substrate 7a.

Abstract: A self-shielding target for isotope production systems is provided. The target includes a body configured to encase a target material and having a passageway for a charged particle beam, and a component within the body, wherein the charged particle beam induces radioactivity in the component. Additionally, at least one portion of the body is formed from a material having a density value greater than a density value of aluminum to shield the component.

Abstract: Disclosed is a target for isotope production, that comprises a porous, nanostructured material with structure elements having in at least one dimension an average size of 700 run or less, preferably 500 nm or less and most preferably 150 nm or less, said nanostructured material comprising one Of Al2O3, Y2O3 and ZrO2.

Abstract: A device, method and system for causing a controlled collapse of cavities formed within liquid droplets wherein a pressurized jet comprising a liquid and nanoparticle material produces droplets from the breakup of the jet stream. The liquid droplets may be irradiated with energy to produce and expand cavities formed within the droplets by irradiation of the nanoparticles contained within the droplets or alternatively, a volatile fluid with or without a metal nanoparticle may form the cavity. The droplets are collided with a target to collapse the cavities within the droplets. The irradiating (if provided) and colliding are timed to enhance implosion energy resulting from the cavities' collapse. The implosion energy and the fuel in the cavity may be used to activate and sustain a fusion reaction or from any other purposes.

Abstract: One embodiment of the present invention includes a process for production and recovery of no-carrier-added radioactive tin (NCA radiotin). An antimony target can be irradiated with a beam of accelerated particles forming NCA radiotin, followed by separation of the NCA radiotin from the irradiated target. The target is metallic Sb in a hermetically sealed shell. The shell can be graphite, molybdenum, or stainless steel. The irradiated target can be removed from the shell by chemical or mechanical means, and dissolved in an acidic solution. Sb can be removed from the dissolved irradiated target by extraction. NCA radiotin can be separated from the remaining Sb and other impurities using chromatography on silica gel sorbent. NCA tin-117m can be obtained from this process. NCA tin-117m can be used for labeling organic compounds and biological objects to be applied in medicine for imaging and therapy of various diseases.

Abstract: Disclosed herein is a high current solid target for radioisotope production at a cyclotron using a metal foam, and more specifically, a high current solid target for isotope production, which attaches a metal foam to the rear surface of the solid target plate. A high current solid target for isotope production including a metal foam according to the present invention may exhibit excellent cooling performances to increase the amount of proton beam current irradiated on the solid target compared to conventional planar-type solid targets. Because the irradiation of the increased proton beam current may increase the amount of an isotope produced per unit time and even an irradiation of proton beam in a short time may allow for production of a desired amount of an isotope, the solid target may be usefully used for production of medical cyclotron nuclides.

Abstract: This invention relates to the generation of a sufficiently high temperature and pressure to ignite a nuclear fusion reaction making fusion economically viable for energy generation. A method to achieve ignition of a nuclear fusion reaction is disclosed. The method uses collision of high-velocity fuel pellets/projectiles that contain nuclear fuel and have tailpieces of high atomic weight. Fusible gas in the pellet is preheated and rapidly compressed by collision impact to heat it to fusion ignition temperature. A major portion of the projectile's kinetic energy is converted during collision impact into thermal energy heating the fusion gas to ignite a fusion reaction. The energy released from the nuclear fusion reaction exceeds the input energy. The excess energy can be harvested for generation of electric power.

Abstract: Target, computer software and method for direct production of 99mTc using small energy accelerators. The method includes positioning a target holder to be bombarded with a beam of protons, the target holder having a target that includes a first hard core layer, a second hard core layer, a third layer of highly enriched 100Mo and a substrate, distributed in this order; bombarding the target with the beam of protons, wherein the protons have an energy between 10 and 35 MeV and a current between 20 and 500 ?A; and terminating the bombarding with the beam of protons after a time interval between half an hour and 8 hours.

Abstract: A system for fueling a plasma includes a gyrotron for radiating microwave energy into a waveguide. Also included is a module having a deuterium-tritium (DT) fuel pellet, a diamond, quartz or sapphire window, and a pusher medium located between the pellet and window that is made of frozen deuterium (D2) and metallic particles. With the module in the waveguide, the gyrotron is activated. Radiation from the gyrotron is then directed into the waveguide and through the window to cause the inducement of current in the metal particles, causing the particles to become hot. The absorbed microwave energy is then transferred to the pusher medium by conduction resulting in a gaseous expansion of the pusher medium. This ejects the pellet from the waveguide and into the plasma.

Abstract: A particle beam target for producing radionuclides includes a target body, a target cavity, parallel grooves, peripheral bores, and radial outflow bores. The parallel grooves are formed in a back side of the target body and include respective first and second groove ends. The peripheral bores extend through the target body from the plurality of grooves generally toward the front side that receives a particle beam. Each groove communicates with a peripheral bore at the first groove end and another peripheral bore at the second groove end. The radial outflow bores extend radially from the plurality of peripheral bores. The target body defines a plurality of liquid coolant flow paths. Each liquid coolant flow path runs from a respective groove to at least one of the first groove end and the second groove end of the respective groove, through at least one peripheral bore, and through at least one radial outflow bore.

Abstract: The invention relates to nuclear technology, and to irradiation targets and their preparation. One embodiment of the present invention includes a method for preparation of a target containing intermetallic composition of antimony Ti—Sb, Al—Sb, Cu—Sb, or Ni—Sb in order to produce radionuclides (e.g., tin-117m) with a beam of accelerated particles. The intermetallic compounds of antimony can be welded by means of diffusion welding to a copper backing cooled during irradiation on the beam of accelerated particles. Another target can be encapsulated into a shell made of metallic niobium, stainless steel, nickel or titanium cooled outside by water during irradiation. Titanium shell can be plated outside by nickel to avoid interaction with the cooling water.

Abstract: A system and method are provided for reclaiming an enriched radioisotope starting material (14) from a target body (12). The system and method enable reclaiming the starting material in a relatively short time (e.g., several hours) after the target body's bombardment with energetic particles, greatly simplifying the target body's chemical processing, as well as reducing the cost of such processing (e.g., reducing the need for costly long-term storage). Specifically, a chemical protective layer (16) is disposed between a radioisotope starting material (14) and a base material (18) of the target body (12). After the target body is irradiated with a suitable source (e.g., particle accelerator), then the irradiated radioisotope starting material and be removed without removing the base material due to the protection provided by the chemical protective layer.

Abstract: The Hydrogen-Lithium Fusion Device is a revolutionary new device that consists of a proton accelerator, lithium foil target, and a target holder of specified geometry. The invention enables a proton-lithium fusion efficiency that is close to 100% and the fusion byproducts to exit the lithium target without transferring significant fusion energy to the target as heat. Particular aspects of the present invention are described in the claims, specification and drawings.

Abstract: A cylindrical gamma generator includes a coaxial RF-driven plasma ion source and target. A hydrogen plasma is produced by RF excitation in a cylindrical plasma ion generator using an RF antenna. A cylindrical gamma generating target is coaxial with the ion generator, separated by plasma and extraction electrodes which has many openings. The plasma generator emanates ions radially over 360° and the cylindrical target is thus irradiated by ions over its entire circumference. The plasma generator and target may be as long as desired.

Abstract: An experimental machine (1) for producing low-temperature nuclear fusion reactions, wherein an ion source (3) feeds a flux of positive deuterium ions to a reaction chamber (2) housing a target (5) defined by active elements (30, 31) and by an aggregate of metal sulfate hydrated with heavy water; a pumping assembly (4) being provided to maintain a vacuum in the reaction chamber (2); and the reaction chamber (2) having an accelerating device (10) for accelerating the positive deuterium ions, and which generates an electric field inside the reaction chamber (2) to convey and accelerate the deuterium ions against the active element of the target (5) in such a manner as to initiate nuclear fusion reactions between the incident deuterium ions and some of the atoms of the active element.

Abstract: A steady-state source of neutrons is produced within an electrically grounded and temperature controlled chamber confining tritium or deuterium plasma at a predetermined density to effect implantation of ions in the surface of a palladium target rod coated with diffusion barrier material and immersed in such plasma. The rod is enriched with a high concentration of deuterium atoms after a prolonged plasma ion implantation. Collision of the deuterium atoms in the target by impinging ions of the plasma initiates fusion reactions causing emission of neutrons during negative voltage pulses applied to the rod through a high power modulator. The neutrons are so generated at a relatively high dose rate under optimized process conditions.

Abstract: A pellet carrier disc is movably held between two cooling blocks. The disc is vertically moved, setting its through hole into axial alignment with a first hole of the block. Deuterium gas is supplied into the through hole through the hole, and cooled and solidified, forming a deuterium cylinder. Then, the disc is moved, axially aligning the hole with a second hole of the block. A shaft is thrust into a first end of the deuterium cylinder through the hole, thereby forming a hole in the end of the cylinder. Next, the disc is moved, axially aligning the hole with a third hole of the block. Tritium gas is introduced into the hole of the cylinder through the hole, and cooled and solidified, forming a tritium core. Further, the disc is moved, axially aligning the hole with a fourth hole of the block. A shaft is moved through the hole, causing the second end portion of the deuterium cylinder to project from the hole. The second end portion of the cylinder is cut off.

Abstract: System and apparatus for producing neutron beams having an energy spectrum and intensity suitable for use in neutron capture therapy. The apparatus employs a rotating carriage which supports an annular target support region carrying a target material such as lithium metal. The carriage rotatably positions the target material before the pathway of charged particles generated from an accelerator course of ions. To cool the assemblage, the carriage is formed having an internally disposed chamber within which a coolant is directed from an external source. Because of the centrifugal forces imposed upon this internally-disposed coolant, it is forced to a heat exchange position adjacent the target region. The assemblage of carriage and accelerator are retained within a containment chamber under vacuum.

Abstract: A neutron generator comprising a target (16) which is struck by a hydrogen isotope ion beam and which is formed by a structure comprising a thin absorbing active layer (19) deposited on a carrier layer (18). In accordance with the invention, on the two above layers there is deposited a stack of active layers (21, 23, 25, 27) which are identical to the layer (19) and which are separated from one another by diffusion barriers (20, 22, 24, 26, respectively). The thickness of each of said active layers is in the order of the penetration depth of the deuterium ions striking the target.

Abstract: A method is disclosed for coating a substrate with a uniformly smooth layer of a boron hydride polymer. The method comprises providing a reaction chamber which contains the substrate and the boron hydride plasma. A boron hydride feed stock is introduced into the chamber simultaneously with the generation of a plasma discharge within the chamber. A boron hydride plasma of ions, electrons and free radicals which is generated by the plasma discharge interacts to form a uniformly smooth boron hydride polymer which is deposited on the substrate.

Abstract: An irradiator for irradiating lumps of ore, to activate a selected substance in the ore by neutron activation, consists of a cylindrical chamber 10, a vibrated conical base 20 to control passage of the lumps through the chamber 10, and at least one coaxial annular neutron source 30 at one end of the chamber 10. The neutron source 30 is arranged so that all the lumps of ore are activated uniformly.

Abstract: A high energy neutron generator for use in neutron therapy.The generator comprises a source for charged particles (preferably protons) with an energy level equal to at least 15 MeV, a target constituted by at least two lithium deuteride elements, whose thickness is such that under the impact of the charged particles, neutrons with an energy level equal to at least 15 MeV are largely produced in the forward direction, and target cooling means constituted by means for the circulation of a gas which does not chemically react with lithium deuteride. This generator may also comprise a collimator for defining an irradiation field of a patient and a permanent magnet able to deflect the charged particles not absorbed by the target towards a stopping unit positioned in and integrally formed with one wall of the collimator.

Abstract: A simple apparatus for removably holding a plurality of microballoons during filling and determination of the pressure of the gas fill. The subject apparatus permits the manipulation of substantial numbers of microballoons necessary for the rapidly growing requirements for these capsules.

Abstract: A target arrangement for spallation-neutron-sources, according to which target material is continuously present at the point of incidence of a proton beam. The target material is arranged at the periphery of a rotary wheel which is internally cooled.

Abstract: Extremely small, three-dimensional articles, such as fusion targets having glass shells (20 to 500 microns in diameter) are coated with alternate layers of colloidal materials. This is accomplished by depositing particles of opposite charge from colloidal suspensions (sols). Articles to be coated are suspended within a drop held in the open end of a closed capillary tube, and colloidal particles are deposited by dipping the capillary into the sols. Alternate monolayers of the particles adhere to the surface of the article. Multilayer coatings are built up by repeated alternate deposition of the monolayers from the sols. Between each deposition, the layers are rinsed with water and the water removed by dipping the capillary tube into a bath of water and then into a bath containing a water displacing agent such as ethanol or dimethyl sulfoxide.

Abstract: Very smooth polymeric coatings or films graded in atomic number and density can readily be formed by first preparing the coating or film from the desired monomeric material and then contacting it with a fluid containing a metal or a mixture of metals for a time sufficient for such metal or metals to sorb and diffuse into the coating or film. Metal resinate solutions are particularly advantageous for this purpose. A metallic coating can in turn be produced on the metal-loaded film or coating by exposing it to a low pressure plasma of air, oxygen, or nitrous oxide. The process permits a metallic coating to be formed on a heat sensitive substrate without the use of elevated temperatures.

Abstract: Foam encapsulated laser-fusion targets wherein a quantity of thermonuclear fuel is embedded in low density, microcellular foam which serves as an electron conduction channel for symmetrical implosion of the fuel by illumination of the target by one or more laser beams. The fuel, such as DT, is contained within a hollow shell constructed of glass, for example, with the foam having a cell size of preferably no greater than 2 .mu.m, a density of 0.065 to 0.6.times.10.sup.3 kg/m.sup.3, and external diameter of less than 200 .mu.m.

Abstract: A method is provided for producing solid, evacuated microspheres comprised of hydrogen. The spheres are produced by forming a jet of liquid hydrogen and exciting mechanical waves on the jet of appropriate frequency so that the jet breaks up into drops with a bubble formed in each drop by cavitation. The drops are exposed to a pressure less than the vapor pressure of the liquid hydrogen so that the bubble which is formed within each drop expands. The drops which contain bubbles are exposed to an environment having a pressure just below the triple point of liquid hydrogen and they thereby freeze giving solid, evacuated spheres of hydrogen.

Abstract: A target arrangement for spallation-neutron-sources, according to which tet material is continuously present at the point of incidence of a proton beam. The target material is arranged at the periphery of a rotary wheel which is internally cooled.

Abstract: Extremely small, three-dimensional articles, such as fusion targets having glass shells (20 to 500 microns in diameter) are coated with alternate layers of colloidal materials. This is accomplished by depositing particles of opposite charge from colloidal suspensions (sols). Articles to be coated are suspended within a drop held in the open end of a closed capillary tube, and colloidal particles are deposited by dipping the capillary into the sols. Alternate monolayers of the particles adhere to the surface of the article. Multilayer coatings are built up by repeated alternate deposition of the monolayers from the sols. Between each deposition, the layers are rinsed with water and the water removed by dipping the capillary tube into a bath of water and then into a bath containing a water displacing agent such as ethanol or dimethyl sulfoxide.