Abstract: A method for manufacturing a decorated article having a smooth printing surface by performing an inkjet printing to an uneven surface of a carbon fiber reinforced plastic molding. An uncured rough-surface ink layer is formed on an undecorated uneven surface by performing an inkjet printing and using an active energy ray curable ink, and a temporary cover film is disposed to cover an upper surface of the uncured rough-surface ink layer. The surface of the uncured rough-surface ink layer is smoothed by applying a pressing force to the uncured rough-surface ink layer from the upper surface of the temporary cover film. An active energy ray is applied, so that a cured smooth ink layer is formed, and the temporary cover film is peeled.

Abstract: A sandwich structure for enhancement of photoluminescence (PL) from luminescent films and the corresponding preparation method are disclosed. The sandwich structure comprises a support, a luminescent film grown on the support, and a single-layer close-packed microsphere array deposited onto the luminescent film. The microspheres have high transmittance excitation light and emitted light, respectively. The low price of dielectric microspheres is beneficial to industrial applications. The stable chemical properties of dielectric microspheres make PL enhanced in a long term. Both metal and non-metal materials can be used as the support in the sandwich structure. These features significantly improve the technique of PL enhancement for luminescent films.

Abstract: A roofing material composition and a method of applying that roofing material composition using specific angles to deflect infra-red rays and provide aesthetically nice finish is disclosed. The first coat of the roofing material is light in color and the second color may be a light or a dark color. The rough surface is prepared using specific filler, resin and paint to deflect infra-red rays and reduce heating inside a building.

Abstract: Systems and methods are provided for coating interior surfaces of products with coating material. The systems and methods can include at least one plug to selectively close an opening of the product, wherein the plug is movable relative to the opening between a first position in which the plug is retracted from the opening and a second position in which the plug is engaged with the opening to seal the opening. When the plug is in the second position, a pump delivers coating material to the cavity of the product via a fluid line and a port in the plug. The coating material can fill the cavity, and an electrode can be energized to coat the interior surface of the product with an electrophoretic deposition process. Other coating processes can also be used in a similar manner.

Abstract: The present invention provides a method for printing and coating a flexible substrate web so as to attain a specified coefficient of friction on both sides of the substrate web which employs the use of controlled set-off of coated and/or printed material from the front side to the back side side of the web. Furthermore the method provides a substrate web produced therefrom and the method is useful for packaging substrate webs and, in particular, foil substrate webs.

Abstract: This coated steel sheet comprises: a steel sheet; a primer coating film that is arranged on the steel sheet and contains a chromic acid-based rust preventive pigment and aggregate that serves as primary particles, while not containing porous particles; and a top coating film that is arranged on the primer coating film. The aggregate satisfies the following formula (1) and formula (2). D10?0.6T (1) D90<2.0T (2) (In the formulae, D10 represents the 10% particle diameter (?m) of the aggregate in the number-based cumulative particle size distribution; D90 represents the 90% particle diameter (?m) of the aggregate in the number-based cumulative particle size distribution; and T represents the film thickness (?m) of a portion of the primer coating film, in which the aggregate is not present.

Abstract: A water-based coating composition and method for forming a multi-layer coating film by which it is possible to form a coating film 5 having excellent smoothness, image clarity, and chipping resistance in a 3C1B format. The composition is characterized by containing 7 to 60 mass % of an acrylic resin emulsion (a), 10 to 60 mass % of a film-forming resin (b), and 10 10 to 50 mass % of a curing agent (c), on the basis of the total mass of the solid resin content in the composition; the acrylic resin emulsion (a) having a core/shell structure where the core section contains, as a copolymer component, 0.1 to 10 mass % of a polymerizable unsaturated 15 monomer having two or more polymerizable unsaturated groups in one molecule, on the basis of the total mass of monomer of the core section, and the hydroxyl value of the core section is 50 to 200 mgKOH/g, and the hydroxyl value of the shell section is 50 to 200 mgKOH/g.

Abstract: Micromachined ultrasonic transducer (MUT) arrays capable of multiple resonant modes and techniques for operating them are described, for example to achieve both high frequency and low frequency operation in a same device. In embodiments, various sizes of piezoelectric membranes are fabricated for tuning resonance frequency across the membranes. The variously sized piezoelectric membranes are gradually transitioned across a length of the substrate to mitigate destructive interference between membranes oscillating in different modes and frequencies.

Abstract: The present invention guides the linear vibrations of a needle, obtains stable vibrations and exhibits excellent impact strength, and makes thinness or widthwise compactness possible. A linear vibration motor equipped with: a needle equipped with a magnet and a spindle part; a frame for slidably supporting the needle in one axial direction; a coil for driving the magnet in the one axial direction, and affixed to the frame; and an elastic member for imparting an elastic force to the needle in opposition to the driving force imparted on the magnet. Furthermore, a guide groove extending in the one axial direction is provided in the needle or the frame, and a rolling body for rolling and being guided by the guide groove is provided in the other of the needle and the frame.

Abstract: A linear actuator may include a movable element including a cylindrical permanent magnet; a stationary element including a coil bobbin that surrounds the permanent magnet at an outside in a radial direction; a spring member connected to the movable element and the coil bobbin, and supporting the movable element to be movable in an axial direction in relation to the coil bobbin; a coil wound around the coil bobbin, for configuring a magnetic drive mechanism together with the permanent magnet, the magnetic drive mechanism being structured to drive the movable element in the axial direction; and a gel damper member being sandwiched between the stationary element and the movable element in the axial direction.

Abstract: An apparatus includes a marine seismic source having a volume of gas and a gas reservoir, and the marine seismic source and the gas reservoir are coupled to permit a resonating gas flow to pass therebetween. The apparatus may be a component of a marine seismic survey system. The apparatus may be utilized in a method of marine seismic surveying.

Abstract: An ultrasonic transducer and an ultrasonic probe including the same are provided. The ultrasonic transducer includes a piezoelectric layer configured to convert an electric signal and an ultrasound into each other, and a dematching layer having a uniform thickness, the dematching layer being arranged on a partial region of the piezoelectric layer and configured to reflect the second ultrasound wave that is incident on the dematching layer.

Abstract: Systems, methods and computer readable media for material separation and conveying using tuned waves are disclosed.

Abstract: A high-speed method and system for inspecting a stream of parts using at least one transparent traveling carrier of a conveyor subsystem are provided. The subsystem has a forward reach and a return reach. The method includes controllably receiving a stream of parts in rapid succession on the at least one traveling carrier and utilizing the subsystem to transfer the stream of parts in rapid succession to a part inspection station. The bottom surface of each part is illuminated through its traveling carrier with radiant energy when the part is located at the inspection station to generate reflected radiation signals which travel through its traveling carrier. A bottom image of each illuminated bottom surface is formed from the reflected radiation signals at an imaging location between the forward and return reaches at the inspection station. The bottom images are detected at the imaging location.

Abstract: Disclosed is a drinking straws cleaning system. Embodiments of the present invention discloses a drinking straws cleaning system that includes a flexible tubular elongated shaft including a first end, a second end, a body portion disposed in between the first end and the second end, a holding member configured at the second end, and one or more flaps configured proximal to the holding member at the second end, wherein the flexible tubular elongated shaft is passed through a hollow cavity of a straw through a top opening until the first end of the flexible tubular elongated shaft emerges out of a bottom opening of the straw, and then pulled therethrough to fully emerge out of the hollow cavity of the straw to clean the straw.

Abstract: Devices and techniques related to landfill gas extraction are disclosed. A technique for controlling extraction of landfill gas from a landfill through a gas extraction system is described. The method may include measuring a plurality of values indicating conditions associated with the landfill; computing, based at least in part on the plurality of values and on a model of the landfill, a predicted future state of the landfill; determining, based at least in part on the predicted future state of the landfill, one or more control parameters for one or more respective control devices configured to control operation of the gas extraction system; applying the one or more control parameters to the one or more respective control, and with the one or more control devices, controlling extraction of the landfill gas from the landfill based, at least in part, on the one or more respective control parameters.

Abstract: Devices and techniques related to landfill gas extraction are disclosed. A technique for controlling extraction of landfill gas from a landfill through a gas extraction system is described. The method may include measuring a plurality of values indicating conditions associated with the landfill; computing, based at least in part on the plurality of values and on a model of the landfill, a predicted future state of the landfill; determining, based at least in part on the predicted future state of the landfill, one or more control parameters for one or more respective control devices configured to control operation of the gas extraction system; applying the one or more control parameters to the one or more respective control, and with the one or more control devices, controlling extraction of the landfill gas from the landfill based, at least in part, on the one or more respective control parameters.

Abstract: Devices and techniques related to landfill gas extraction are disclosed. A technique for controlling extraction of landfill gas from a landfill through a gas extraction system is described. The method may include measuring a plurality of values indicating conditions associated with the landfill; computing, based at least in part on the plurality of values and on a model of the landfill, a predicted future state of the landfill; determining, based at least in part on the predicted future state of the landfill, one or more control parameters for one or more respective control devices configured to control operation of the gas extraction system; applying the one or more control parameters to the one or more respective control, and with the one or more control devices, controlling extraction of the landfill gas from the landfill based, at least in part, on the one or more respective control parameters.

Abstract: A well cap assembly is disclosed which is well suited for use with a wellhead. The well cap assembly has a port component and a cap element. The port component has a bore extending therethrough, an upper neck portion, and an upper threaded portion. The port component further has a lower threaded portion and a barb formed on the upper neck portion. The barb can receive an external flexible tube which is temporarily secured to the port component. The cap element has an internally threaded portion which engages with the upper threaded portion of the upper neck portion and seals the bore of the port component. The cap element also has a tether for securing it to the port component.

Abstract: A string of reactant chambers configured for inserting a reactant into each reactant chamber, in the string of reactant chambers, while maintaining the reactant chamber being filled in the string of reactant chambers is provided. The string of reactant chambers has a first reactant chamber, a second reactant chamber, and a system configured to maintain the reactant chamber being filled in the string of reactant chambers. The system has a first removable end cap on each reactant chamber and a coupler on each reactant chamber configured for the removal of the first removable end cap and maintaining the reactant chamber in the string of reactant chambers. A process for charging a reactant chamber is also presently disclosed.

Abstract: A method for producing hot-rolled, seamless pipes having at least one wall thickening which can be arranged at any positions over the length of the pipe, wherein by means of a multiple-stand mandrel bar rolling mill, the rolls roll a hollow shell on a mandrel bar as an inner tool to a required nominal wall thickness and produce at specified positions over the length of the pipe a required wall thickening on the outer side of the pipe by opening the rolls in the rolling stands. The thickened wall is produced and finish-rolled by two rolling stands that are consecutive as seen in the rolling direction, in which the deviations of the finished contour of the thickening from an ideal circular cross-section are minimised, wherein the rolling stands located upstream are likewise opened as to avoid any contact of the rolls of these rolling stands with the previously produced thickening.

Abstract: A tabular negative pressure sheet 3 includes a baseplate 4, a sheet 5 with conduction grooves, a nonwoven cloth lamination outer layer 6, and a surface layer member 7. The baseplate 4 is a member as a base of the tabular negative pressure sheet 3. In addition, the sheet 5 with conduction grooves is a member disposed on the outer side of the baseplate 4, and on the surface thereof, negative pressure conduction grooves 8 are formed. In the tabular negative pressure sheet 3, negative pressure conduction grooves 8 are formed in a direction substantially perpendicular to a direction in which a strip 2 is threaded so that a negative pressure is generated as far as an end portion of the tabular negative pressure sheet 3.

Abstract: The present invention discloses a method for synchronously processing dual belt materials. The method comprises steps of feeding, processing, detecting, assembling and outputting finished products. The step of feeding materials comprises cleaning, dividing materials, positioning and feeding. The step of assembling comprises pushing and assembling. A dual-belt-material feeder is used for feeding, and a dual-belt-material mould is used for punching. The dual-belt-material feeder (1) comprises a moving feeding device (11), a fixed feeding device (13) and two guide frames (14). The dual-belt-material mould comprises two punching moulds. The beneficial effects of the method for synchronously processing dual belt materials are that: the method can be used for producing thin wall miniature assembly parts in a single line and assembling the thin wall miniature assembly parts on line, so that problems caused by that the thin wall miniature assembly parts are produced in two production lines can be avoided.

Abstract: A paintless dent removal (PDR) tool includes a detachable head, tubing assembly and handle. The tubing assembly includes a plurality of tubing segments having different lengths that are detachable and interchangeable. The length of the tubing assembly may be adjusted by attaching together one or more of the tubing segments having different lengths. One or more different types of heads may be attached to the tubing assembly depending on the type of dent to be repaired. One type of head includes a t-bar with two ends, each end configured for attachment to one of a plurality of different types of tips.

Abstract: A device for bending tubular workpieces includes a straight workpiece section that extends in a longitudinal direction and is held in a clamping device. A bending tool for bending the workpiece around a bending axis, that runs transversely to the longitudinal direction, has a radial part and a bending part. The radial part is rotatable about the bending axis. The bending part can be pivoted relative to the radial part for bending the workpiece about the bending axis. For rotatable driving, a radial driveshaft is coupled to the radial part, and a bending driveshaft is coupled to the bending part. To very flexibly create a plurality of different bends and to be able to use variable bend geometries, the radial driveshaft and the bending driveshaft extend in the longitudinal direction. The radial driveshaft and/or the bending driveshaft are designed as a hollow shaft, and one is arranged coaxially around the other.

Abstract: A manufacturing method of a press-formed article includes arranging a member to be pressed between first and second dies, and relatively moving the first and second dies so as to approach each other, thereby press forming to a portion to be pressed so that a height of the portion to be pressed decreases. In the press forming step, while first bent portions in a pair each bent in a protruded shape toward the second die on the portion to be pressed are held by groove-shaped holding portions in a pair separated from each other on the second die, a second bent portion bent in a protruded shape from a position between the first bent portions toward the first die on the portion to be pressed is pressed and deformed by a pressing portion of the first die.

Abstract: A vertical Pittsburgh Seam closing apparatus having a base supporting surface, a track mechanism for moving a carriage assembly which holds seam forming members used to close a Pittsburgh Seam, a pair of upper and lower guide members for guiding the duct section into a proper vertical position, and upper and lower clamping members positioned inside the duct section and adjacent the inside portion of the Pittsburgh Seam to be closed, the upper guide members and clamping member being selectively movable and adjustable for accommodating different duct section lengths. In one embodiment, the seam forming assembly includes three roller members mounted in vertical arrangement to each other, one roller member being V-shaped in configuration and the other two roller members being substantially cylindrical in shape. The V-shaped roller member may also include one or more projecting members for forming dimples in the closing process to prevent shifting and/or slipping of the closed seam.

Abstract: The present invention discloses a device for assembling products in a die. The device comprises a pushing portion and an assembling portion. The pushing portion comprises a pushing block (11), a pushing spring (10) and a pushing wedge (9) wherein the pushing block (11) is connected with the pushing spring (10), the pushing wedge (9) is arranged above the pushing block (11) and is in wedge-shaped connection with the pushing block (11). The assembling portion comprises an assembling wedge (6), a transmission wedge (4) and an assembling male die (5), wherein the transmission wedge (4) is arranged above the assembling male die (5) in wedge-shaped connection and both of them are arranged in the lower die base (2), the assembling wedge (6) is arranged above the transmission wedge (4) in wedge-shaped connection while in contact.

Abstract: A handheld loop former for beading wire is provided. The loop former comprises a cutting lever, a slotted forming platform, a forming lever, and two scissors links. The cutting lever has a combination shear blade/forming die at its distal end. The slotted forming platform has a medially located slot, a shearing ledger, and a forming stanchion. The forming lever has a second forming die at its distal end. The cutting lever, forming platform at the medially located slot, and forming lever are journaled together with a pivot pin. Each of the forming lever and the cutting lever is journaled to one of the scissors links. Both scissors links are journaled to the forming platform. The sheer blade/forming die passes closely to the shearing ledger and with the second forming die envelops the forming stanchion when the forming lever and cutting lever are urged together. The forming platform is drawn proximally.

Abstract: The invention relates to a method for producing a flat spiral spring, in particular a spring sheet for covering a cooling area of a piston of internal combustion engines, said spring sheet being formed at least as an annular disk-shaped segment (12), wherein a strip-shaped material (23) is fed to a bending device (27) that comprises at least one drum (29), said drum rotating about a rotational axis (31), and the strip-shaped material (23) is supplied in a tangential alignment to the lateral surface (36) of the drum (29) such that a lateral wall (20) which determines the thickness of the strip-shaped material (23) rests against at least some sections of a contact surface (37) on the lateral surface (36) of the drum (29).

Abstract: The present invention relates to a method for manufacturing a round-rod shaped alloy ingot by hot forging, containing suspending a primary alloy ingot having a round-rod shape in a columnar mold while one end of the primary alloy ingot is held, pouring a molten metal formed of a heat-retaining metal into the columnar mold so as to apply a coating of the heat-retaining metal to the entire circumference of the primary alloy ingot, to obtain a forging alloy ingot, taking the forging alloy ingot out from the columnar mold, then subjecting the forging alloy ingot to a hot forging while an end portion of the forging alloy ingot is gripped as a gripping portion, and removing the coating of the heat-retaining metal.

Abstract: Apparatus (20, 22) and a method for mechanically joining a steel sheet portion (28 or 32) of advanced high strength steel to a metallic sheet portion (30 or 34) is performed to a light-safe extent by a detector assembly (106) during the mechanical joining that may be clinching, clinch riveting, full-punch riveting or self-piercing riveting.

Abstract: A method for semi-continuous casting of a strand (1) of steel in a strand casting machine and a strand casting machine for such casting. The strand has little segregation of the center and porosity. Yet it is castable rapidly. The method steps are: at a casting start of the strand casting machine, pouring liquid steel into an open-ended mold (2). The mold is closed by a cold strand (6). The liquid steel forms, together with the cold strand, a completely solidified strand start (1a) and subsequently forms a semi-solidified strand (1b). Then extracting the semi-solidified strand (1b) from the open-ended mold (2). Supporting and guiding the semi-solidified strand (1b) in a strand guide (3). Cooling the semi-solidified strand (1b) by secondary cooling (4) at the casting end of the strand casting machine, ending the pouring of liquid steel into the open-ended mold (2) and forming a strand end (1c). Extracting the strand end (1c) from the open-ended mold (2).

Abstract: A method of controlling molten metal flow and an electromagnetic brake system for a metal-making process, including: a first magnetic core arrangement having a first and second long sides with Nc teeth, and arranged to be mounted to opposite longitudinal sides of an upper portion of a mould, a first set of coils, each being wound around a respective tooth of the first magnetic core arrangement, and Np power converters, with Np being an integer that is at least two and Nc is an integer that is at least four and evenly divisible with Np, wherein each power converter is configured to feed a DC current to its respective group of 2Nc/Np series-connected coils.

Abstract: A manufacturing method for a cast bar and tube made of a magnesium alloy, includes steps of preparing a manufacturing device; depressurizing a vacuum chamber through a depressurization device; heating a vicinity of an opening of a hollow tube; inserting the opening of the hollow tube into a molten metal; switching a valve member to be open; introducing the molten metal into a cylindrical part, and filling the cylindrical part with the molten metal; cooling the hollow tube; and continuously vibrating the hollow tube until completing solidification of the molten metal in the cylindrical part.

Abstract: The invention relates to a method (S) for manufacturing a part (1) out of a metal matrix composite material, including the following steps: opening (S1) device (10) that includes a supporting portion (14) and a molding portion (14); placing (S2) a fibrous reinforcement into the device (10); sealably closing (S3) the device (10) by providing a space between the fibrous reinforcement (2) and the device portions; feeding (S4) the molten metal matrix (3) into the device (10) such as to fill the space between the fibrous reinforcement (2) and the device portions (13, 14); and applying (S5) a force onto the equipment (10) such as to impregnate the fibrous reinforcement (2) with the metal matrix (3).

Abstract: An apparatus for the simultaneous casting of multiple components using a directional solidification process includes; a pouring cup arranged on a centreline, an array of moulds encircling the pouring cup and centre line, an array of feed channels extending from the pouring cup to a top end of each mould, and a heat deflector. The heat deflector comprises a wall arranged between the array of moulds and the centreline extending along the length of the moulds and in thermal contact with the moulds.

Abstract: A silver powder, wherein the silver powder satisfies D50-IPA>D50-W, where in measurement of a volume-based particle size distribution of the silver powder by a laser diffraction particle size distribution analysis, D50-IPA (?m) is a cumulative 50% point of particle diameter of the silver powder when isopropyl alcohol (IPA) is used as a measurement solvent for dispersing the silver powder, and D50-W (?m) is a cumulative 50% point of particle diameter of the silver powder when water is used as a measurement solvent for dispersing the silver powder, and wherein a phosphorus content in the silver powder is 0.01% by mass or more but 0.3% by mass or less.

Abstract: There is provided conductive paste excellent in electro-conductivity and thermal conductivity. Conductive paste comprising conductive filler being composite particles including copper powder and nanosize precipitates which are disposed on the surface of the copper powder and composed of at least one kind of transition metal belonging to the group 8 to group 10 of the periodic table or a compound of the transition metal, and a binder resin.

Abstract: The invention relates to a manufacturing system and method for manufacturing a part. A negative powder forms a holder suitable to hold particles of a positive powder in proximity to one another. A connection scheme such as heating, the use of pressure and/or a binder, when employed, connects the particles to one another to form the part.

Abstract: A device (1), for producing a three-dimensional object (2) by solidifying, layer-by-layer, building material (13) at locations in the respective layer corresponding to the cross-section of the object (2) to be produced, contains a flow device (31, 32, 34, 35) for generating a gas flow above an applied layer of the building material (13) by means of a nozzle element (40) for introducing the gas into the device. The nozzle element (40) comprises a body (41) with a gas inlet side and a gas outlet side (46), and a plurality of channels (42) which penetrate the body from the gas inlet side (44) to the gas outlet side (46), are provided with inlet openings on the gas inlet side (44) and with gas outlet openings (47) on the gas outlet side (46), and which are separated by walls (43). The length of the channels (42) is selected such that therein a laminar flow is formed at the gas outlet side (46).

Abstract: A method for producing a sensor on the surface of a functional layer, in which suitable sensor material in the form of powder or a wire is melted in a laser beam by way of a method similar to laser cladding and subsequently is applied to the surface of the functional layer. There is provided a considerably improved method for producing sensors, and in particular in-situ sensors, wherein the sensors can also be deposited onto a functional layer that, in part, is very coarse, without having to employ complex masks, as has previously been customary. The ease of adapting the method parameters ensures broad use both with respect to the sensor to be produced and the functional layer to be detected. The sensors thus produced are used, in particular, to detect components that are subject to high temperatures or the functional layers thereof. The sensors that can be produced in accordance with the invention include, in particular, temperature, pressure or voltage sensors, as well as acceleration sensors.

Abstract: Systems and methods directed fabrication using multi-material and precision alloy droplet jetting.

Abstract: A method for removing prior particle boundaries and hole defects of a powder metallurgy high-temperature alloy. The method includes performing mechanical ball milling treatment on an atomized powder, thermosetting the powder to form a shape, and preparing a powder metallurgy high-temperature alloy.

Abstract: Sintering tool (10) with a cradle for receiving an electronic subassembly (BG) to be sintered, characterized by at least one support bracket (20), arranged at two locations opposite the cradle, for fixing a protective film (30) covering the electronic subassembly (BG).

Abstract: A component includes an additively manufactured component with an internal passage; and an additively manufactured elongated member within the internal passage. A method of additively manufacturing a component including additively manufacturing a component with an internal passage; and additively manufacturing an elongated member within the internal passage concurrent with additively manufacturing the component.

Abstract: Process for additive manufacturing of at least one part. At least one layer of powder is deposited on a working surface using a layering device for distributing the powder mobile in translation along the surface and at least partly fusing the layer deposited using a beam of energy. The depositing and fusing steps are repeated in order to form the part by stacking of fused layers. The distribution component of the layering device is mobile in a direction substantially parallel to the direction of the length of each fused layer of the part. The depositing and fusing steps are repeated in order to form the part so that the length of the part extends along a direction substantially parallel to the stacking direction of the fused layers and so that the head of the part is oriented substantially perpendicular to the working surface.

Abstract: According to the present invention, there are provided processes for preparing a porous composite material comprising a metal and a two-dimensional nanomaterial. In one aspect, the processes comprise the steps of: providing a powder comprising metal particles; heating the powder such that the metal particles fuse to form a porous scaffold; and forming a two-dimensional nanomaterial on a surface of the porous scaffold by chemical vapour deposition (CVD). Also provided are materials obtainable by the present processes, and products comprising said materials.

Abstract: A soft magnetic nanoparticle comprising an iron aluminide nanoalloy of the DO3 phase as a core encapsulated in an inert shell made of alumina.

Abstract: The invention relates to nano-particles comprising metallic ferromagnetic nanocrystals combined with either amorphous or graphitic carbon in which or on which chemical groups are present that can dissociate in aqueous solutions. According to the invention there is provided nano-particles comprising metal particles of at least one ferromagnetic metal, which metal particles are at least in part encapsulated by graphitic carbon. The nano-particles of the invention are prepared by impregnating carbon containing bodies with an aqueous solution of at least one ferromagnetic metal precursor, drying the impregnated bodies, followed by heating the impregnated bodies in an inert and substantially oxygen-free atmosphere, thereby reducing the metal compounds to the corresponding metal or metal alloy.