Abstract: A surgical system includes a surgical instrument and a cooling module. The cooling module includes a fluid reservoir retaining a conductive cooling fluid, a pump configured to pump the conductive cooling fluid along a flowpath, first and second electrodes disposed at first and second positions along the flowpath and configured to sense an electrical property of the conductive cooling fluid at the first and second positions, and a controller configured to determine an impedance of the conductive cooling fluid between the first and second positions based upon the sensed electrical properties of the first and second electrodes. A method for cooling a surgical instrument includes detecting an electrical property of a conductive cooling fluid at first and second positions along a flowpath and determining an impedance of the conductive cooling fluid between the first and second positions based upon the detected electrical properties at the first and second positions.

Abstract: A process for the production of nanocrystals or amorphous nanoparticles of actives (nanomaterials), especially from the peels of grapes. A dispersion of a micrometer-sized material in a solution of surfactant or a steric stabilizer is first provided. The macrosuspension is then stirred for at least 1 minute at a rotational speed above 500 rpm using a rotor-stator mixer. The stirred mixture is passed through a jet stream or piston-gas type high pressure homogenizer. The nanomaterials produced can be incorporated into formulations for use as nutraceutical, nutritional supplement, or as supportive treatment in medical therapy. The active can be derived from the peels of grapes.

Abstract: A method for making a metal-based nano-composite material is disclosed. In the method, a semi-solid state metal-based material is provided. The semi-solid state metal-based material is stirred and nano-sized reinforcements are added into the semi-solid state metal-based material to obtain a semi-solid state mixture. The semi-solid state mixture is heated to a temperature above a liquidus temperature of the metal-based material, to achieve a liquid-metal-nano-sized reinforcement mixture. The liquid-metal-nano-sized reinforcement mixture is ultrasonically processed at a temperature above the liquidus temperature by conducting ultrasonic vibrations to the liquid-metal-nano-sized reinforcement mixture along different directions at the same time.

Abstract: Methods are disclosed for synthesizing nanocomposite materials including ferromagnetic nanoparticles with polymer shells formed by controlled surface polymerization. The polymer shells prevent the nanoparticles from forming agglomerates and preserve the size dispersion of the nanoparticles. The nanocomposite particles can be further networked in suitable polymer hosts to tune mechanical, optical, and thermal properties of the final composite polymer system. An exemplary method includes forming a polymer shell on a nanoparticle surface by adding molecules of at least one monomer and optionally of at least one tethering agent to the nanoparticles, and then exposing to electromagnetic radiation at a wavelength selected to induce bonding between the nanoparticle and the molecules, to form a polymer shell bonded to the particle and optionally to a polymer host matrix. The nanocomposite materials can be used in various magneto-optic applications.

Abstract: Coding systems may include an object and a taggant linked to the object, the taggant comprising one or more types of phase change nanoparticles, each type of phase change nanoparticles having a phase change temperature different from a phase change temperature of other types of phase change nanoparticles, wherein, when the taggant is thermally scanned, different phase change temperatures result in one or more predefined melting peaks forming a code that represents information particular to the object.

Abstract: Methods for fabricating sublithographic, nanoscale microstructures in line arrays utilizing self-assembling block copolymers, and films and devices formed from these methods are provided. Semiconductor structures may include self-assembled block copolymer materials in the form of lines of half-cylinders of a minority block matrix of a majority block of the block copolymer. The lines of half-cylinders may be within trenches in the semiconductor structures.

Abstract: A quantum dot-resin nanocomposite including a nanoparticle including a curable resin and a plurality of quantum dots contacting the nanoparticle. Also, a method of preparing the nanocomposite, and a molded article including the nanocomposite.

Abstract: A semiconductor of which a substance such as a semiconductor photocatalyst is uniformly coated on the surface thereof with a graphitic carbon film and a method of fabricating the same are disclosed. According to the inventive method, a graphitic carbon film having a thickness of 1 nm or less is uniformly formed on the surface of the semiconductor by performing hydrothermal synthesis and pyrolysis on glucose, so as to keep the original structure crystallinity of the semiconductor photocatalyst to be a support of the carbon film.

Abstract: According to a method for manufacturing a sheet-like heating element and a sheet-like heating element manufactured by the method of the present invention, cubics are pulverized into nanoparticles, the nanoparticle powder is mixed with carbon to become an original yarn, and the original yarn is cut to a length of between 0.2 mm and 0.8 mm and mixed into a pulp liquid to be formed into nanoparticle pulp. The sheet-like heating element forms a space where the particles can be rotated so as to allow 90% or higher far infrared radiation, and thus contributes to the health of users, entails a low defective rate since no bending occurs during the manufacturing, can be manufactured in quantity at low cost, and can be used for multiple purposes.

Abstract: It is an object of the present invention to obtain an optically transparent nano-dispersed polymer blend extrudate and a transparent resin having a microscopic dispersion structure in which incompatible polymer blend is melted and kneaded, one of resins is formed into a matrix, a size of dispersed phase of the other resin is controlled to 300 nm or less, more preferably 100 nm or less. Extra additive such as a compatibilizer is not added. When the incompatible polymer blend is melted and kneaded using a high shearing and forming apparatus having an inner feedback type screw under a condition that the screw rotation speed is 600 rpm to 3000 rpm, the rotation speed of the inner feedback type screw is increased, the kneading time is set under constant rotation speed, the high shearing forming condition is adjusted, and a structure in which a size of dispersed phase is controlled to 300 nm or less, more preferably 100 nm or less is formed.

Abstract: This invention provides novel nanofiber enhanced surface area substrates and structures comprising such substrates for use in various medical devices, as well as methods and uses for such substrates and medical devices. In one particular embodiment, methods for enhancing cellular functions on a surface of a medical device implant are disclosed which generally comprise providing a medical device implant comprising a plurality of nanofibers (e.g., nanowires) thereon and exposing the medical device implant to cells such as osteoblasts.

Abstract: Provided is a fluorescent powder of halogen-silicate containing nano-metal particles with the formula of CaX2.y(Ca1-a-bEuaMnbO).SiO2:zM, wherein X is fluorin or/and chlorine, y is 1 or 2, z is molar ratio of nano-metal particles and fluorescent powder CaX2.y(Ca1-a-bEuaMnbO).SiO2, 0<z?1×10?2, 0<a?0.3, 0?b?0.3. The method for preparing the fluorescent powder is also provided. For the surface plasma resonance effect occurring on the surface of the nano-metal particles, the fluorescent powder has stronger luminous intensity. The preparation method is simple to operate, no pollution, easy to control, easy to produce in industry, and can be widely used in the preparation field of fluorescent powder.

Abstract: Methods for fabricating sublithographic, nanoscale microstructures in line arrays utilizing self-assembling block copolymers, and films and devices formed from these methods are provided. Semiconductor structures may include self-assembled block copolymer materials in the form of lines of half-cylinders of a minority block matrix of a majority block of the block copolymer. The lines of half-cylinders may be within trenches in the semiconductor structures.

Abstract: Hydrotalcite particles having an extremely small average secondary particle diameter and a production process therefor. A resin composition comprising hydrotalcite fine particles and having excellent transparency and a molded article thereof. The hydrotalcite fine particles have an average secondary particle diameter measured by a dynamic light scattering method of 5 to 100 nm.

Abstract: An exemplary method of manufacturing a light-absorbing layer and a method of manufacturing a semiconductor device including the same light-absorbing layer are provided. The exemplary method includes: forming a nanoparticles film by applying a semiconductor nanoparticles solution on a substrate; thermally treating the nanoparticles film at least one time to cause adhesion among the nanoparticles; and forming a light-absorbing layer by applying a light-absorbing solution on the nanoparticles film.

Abstract: Matrixes doped with semiconductor nanocrystals are provided. In certain embodiments, the semiconductor nanocrystals have a size and composition such that they absorb or emit light at particular wavelengths. The nanocrystals can comprise ligands that allow for mixing with various matrix materials, including polymers, such that a minimal portion of light is scattered by the matrixes. The matrixes are optionally formed from the ligands. The matrixes of the present invention can be used as refractive index matching components, filters and antireflective coatings on optical devices and as down-converting layers. Processes for producing matrixes comprising semiconductor nanocrystals are also provided. Nanostructures having high quantum efficiency, small size, and/or a narrow size distribution are also described, as are methods of producing indium phosphide nanostructures and core-shell nanostructures with Group II-VI shells.

Abstract: The invention provides a process for the production of a solid polymer with embedded luminescent nano particles, comprising (1) mixing luminescent nano particles with an outer surface coated with capping molecules comprising a first functional group and a second functional group and a precursor of a solid polymer, and (2) allowing the solid polymer to be formed; wherein the first functional group is configured to bind to the outer surface of the quantum dot and the second functional group is miscible with the precursor of the solid polymer and/or is able to react with the precursor of the solid polymer. The invention also provides a luminescent polymeric article comprising a solid polymer with in the polymer article embedded luminescent nano particles with an outer surface coated with capping molecules comprising a first functional group and a second functional group.

Abstract: A method of making a transparent conductive film includes the steps of: providing a carbon nanotube array. At least one carbon nanotube film extracted from the carbon nanotube array. The carbon nanotube films are stacked on the substrate to form a carbon nanotube film structure. The carbon nanotube film structure is irradiated by a laser beam along a predetermined path to obtain a predetermined pattern. The predetermined pattern is separated from the other portion of the carbon nanotube film, thereby forming the transparent conductive film from the predetermined pattern of the carbon nanotube film.

Abstract: A porous body consists essentially of a plurality of ceramic particles having an average size ranging from 8 to 100 nm. The ceramic particles are bonded to adjacent ceramic particles with a strength sufficient to render the porous body self-supporting. The porosity ranges from 30 to 70 vol. % and the average pore size ranges from 5 to 50 nm. The porous body may be manufactured by preparing a dispersion comprising the ceramic particles and a polymer matrix material in a solvent, removing the solvent by heating and/or evaporation, forming a preform of the dried material, and firing the preform to remove the polymer matrix material and bond the ceramic particles to each other. The porous body is useful as a filter element in a system adapted to remove nanoscale particles from a fluid stream.

Abstract: The present disclosure relates to a pressure sensor having a nanostructure and a method for manufacturing the same. More particularly, it relates to a pressure sensor having a nanostructure attached on the surface of the pressure sensor and thus having improved sensor response time and sensitivity and a method for manufacturing the same. The pressure sensor according to the present disclosure having a nanostructure includes: a substrate; a source electrode and a drain electrode arranged on the substrate with a predetermined spacing; a flexible sensor layer disposed on the source electrode and the drain electrode; and a nanostructure attached on the surface of the flexible sensor layer and having nanosized wrinkles.

Abstract: In certain embodiments, a material comprising one or more semiconductive substances is vaporized to generate a vapor phase condensate. The vapor phase condensate is allowed to form nanoparticles. The nanoparticles are annealed to yield substantially spherical nanoparticles.

Abstract: The present invention relates to a metal nanobelt and a method of manufacturing the same, and a conductive ink composition and a conductive film including the same. The metal nanobelt can be easily manufactured at a normal temperature and pressure without requiring the application of high temperature and pressure, and also can be used to form a conductive film or conductive pattern that exhibits excellent conductivity if the conductive ink composition including the same is printed onto a substrate before a heat treatment or a drying process is carried out at low temperature. Therefore, the metal nanobelt and the conductive ink composition may be applied very appropriately for the formation of conductive patterns or conductive films for semiconductor devices, displays, solar cells in environments requiring low temperature heating. The metal nanobelt has a length of 500 nm or more, a length/width ratio of 10 or more, and a width/thickness ratio of 3 or more.

Abstract: Apparatuses for and methods of nano-material powder preservation and dispersion in liquid, capture, and treatments are disclosed. The applications of the present disclosure ensure powder accountability of the nano-materials preventing the nano material from dispersing into the air. The method of treating a nano-material comprises receiving a nano-material and mixing/dispersing the nano-material with a fluid in a vessel until the nano-material is sealed by the fluid. The apparatus for treating a nano-material comprises a hermetically sealable vessel containing a nano-material and a fluid, wherein the fluid is configured to increase the isolation between particles of the nano-material.

Abstract: The present invention provides a hybrid powder of halloysite nanotubes and light-scattering nanoparticles, a method for preparing the same, and a UV-screening cosmetic composition containing the same as an active ingredient. The hybrid powder of halloysite nanotubes and light-scattering nanoparticles according to the present invention, in which the light-scattering nanoparticles are loaded into the halloysite nanotubes, can prevent the light-scattering nanoparticles from penetrating the skin, which minimizes side effects, and has excellent UV-screening effect. Thus, the hybrid powder of halloysite nanotubes and light-scattering nanoparticles according to the present invention can be effectively used as a UV-screening cosmetic composition.

Abstract: In certain embodiments, a material comprising one or more semiconductive substances is vaporized to generate a vapor phase condensate. The vapor phase condensate is allowed to form nanoparticles. The nanoparticles are annealed to yield substantially spherical nanoparticles.

Abstract: A metal nanoparticle composite is provided, in which a matrix resin layer and metal nanoparticles are immobilized on the matrix resin layer. The metal nanoparticle composite has the following characteristics: a) the metal nanoparticles are obtained by heat-reducing metal ions or metal salts contained in the matrix resin layer or a precursor resin layer thereof; b) the metal nanoparticles exist within a region from the surface of the matrix resin layer to a depth of at least 50 nm; c) particle diameters of the metal nanoparticles are in the range of 1 nm to 100 nm with the mean particle diameter of greater than and equal to 3 nm; and d) a spacing between adjacent metal nanoparticles is greater than and equal to the particle diameter of a larger one of the adjacent metal nanoparticles.

Abstract: The present invention provides for photonic nanoimprinted silk fibroin-based materials and methods for making same, comprising embossing silk fibroin-based films with photonic nanometer scale patterns. In addition, the invention provides for processes by which the silk fibroin-based films can be nanoimprinted at room temperature, by locally decreasing the glass transition temperature of the silk film. Such nanoimprinting process increases high throughput and improves potential for incorporation of silk-based photonics into biomedical and other optical devices.

Abstract: Matrixes doped with semiconductor nanocrystals are provided. In certain embodiments, the semiconductor nanocrystals have a size and composition such that they absorb or emit light at particular wavelengths. The nanocrystals can comprise ligands that allow for mixing with various matrix materials, including polymers, such that a minimal portion of light is scattered by the matrixes. The matrixes are optionally formed from the ligands. The matrixes of the present invention can be used as refractive index matching components, filters and antireflective coatings on optical devices and as down-converting layers. Processes for producing matrixes comprising semiconductor nanocrystals are also provided. Nanostructures having high quantum efficiency, small size, and/or a narrow size distribution are also described, as are methods of producing indium phosphide nanostructures and core-shell nanostructures with Group II-VI shells.

Abstract: The present invention is a solventless method of producing polymer coated active pharmaceutical ingredient that is taste-masked and may be released in relatively short time. It employs high energy vibrations or acoustic mixing of API particles, water soluble coating material particles and hydrophobic polymer particles, with or without use of other pharmaceutically relevant powders as media. Additionally the method is capable of producing individually coated drug particles without agglomeration or the long drying times associated with solvent based coating methods.

Abstract: The present invention provides a process for producing pristine or non-oxidized nano graphene platelets (NGPs) that are highly conductive. The process comprises: (i) subjecting a graphitic material to a supercritical fluid at a first temperature and a first pressure for a first period of time in a pressure vessel and then (ii) rapidly depressurizing the fluid at a fluid release rate sufficient for effecting exfoliation of the graphitic material to obtain the NGP material. Conductive NGPs can be used as a conductive additive in transparent electrodes for solar cells or flat panel displays (e.g., to replace expensive indium-tin oxide), battery and supercapacitor electrodes, and nanocomposite for electromagnetic wave interference (EMI) shielding and static charge dissipation, etc.

Abstract: An article of manufacture and method of preparation thereof. The article of manufacture and method of making the article includes an eutectic salt solution suspensions and a plurality of nanocrystalline phase change material particles having a coating disposed thereon and the particles capable of undergoing the phase change which provides increase in thermal energy storage.

Abstract: A nano-particle comprising: an interior region comprising a mixed-metal oxide; and an exterior surface comprising a pure metal. In some embodiments, the mixed-metal oxide comprises aluminum oxide and a metallic pinning agent, such as palladium, copper, molybdenum, or cobalt. In some embodiments, the pure metal at the exterior surface is the same as the metallic pinning agent in the mixed-metal oxide in the interior region. In some embodiments, a catalytic nano-particle is bonded to the pure metal at the exterior surface. In some embodiments, the interior region and the exterior surface are formed using a plasma gun. In some embodiments, the interior region and the exterior surface are formed using a wet chemistry process. In some embodiments, the catalytic nano-particle is bonded to the pure metal using a plasma gun. In some embodiments, the catalytic nano-particle is bonded to the pure metal using a wet chemistry process.

Abstract: A method for synthesizing nano particles, including: moving material in a plasma generating space in a first direction; and synthesizing nano particles by cooling the material moved along the first direction, wherein the synthesizing the nano particles may be performed by cooling the material at gradually lower temperatures during the moving thereof in the first direction.

Abstract: Disclosed herein is an apparatus for synthesizing nano particles. The apparatus for synthesizing nano particles is configured to include: a plasma generator that generates plasma; a recovery device that recovers the synthesized nano particles; and a cooler that is disposed between the plasma generator and the recovery device and includes a cooling path where the nano particles are synthesized, while material supplied from the plasma generator is cooled, wherein the cooling path is set to have lower cooling temperatures for each section as going to the moving direction of the nano particles.

Abstract: A method of manufacturing a nanophosphor includes: contacting a nanophosphor raw material and a flux to form a mixture, sintering the mixture to form a nanoprecursor, ball-milling the nanoprecursor, and drying the ball-milled nanoprecursor to form the nanophosphor, wherein an average particle size of the nanophosphor is equal to or more than about 50 nanometers (nm) and equal to or less than about 7 micrometers (um).

Abstract: A method of making a nanoparticle filled dielectric material. The method includes mixing nanoparticle precursors with a polymer material and reacting the nanoparticle precursors mixed with the polymer material to form nanoparticles dispersed within the polymer material to form a dielectric composite.

Abstract: A method of sterilizing a nanoparticle preparation at a high temperature is provided. A plurality of nanoparticles are purified to form the preparation, wherein the nanoparticles comprise at least a core and a shell and the shell comprises one or more ligand species attached to the core. The nanoparticle preparation is made by a purified nanoparticle composition, a carrier fluid and an excess of the one or more ligand species not attached to the core. The ligand species attached to the core and the excess ligand species added after purification are structurally identical. The nanoparticle preparation provided by the present invention may be used as contrast agents in medical imaging techniques such as X-ray and magnetic resonance imaging.

Abstract: A method for producing and/or processing polymer/carbon nanotube mixtures in powder form comprises the step of grinding a mixture comprising carbon nanotubes and polymer particles. The grinding is carried out in the presence of from ?0 weight-% to ?15 weight-%, expressed in terms of the total weight of the mixture, of a liquid phase which does not dissolve the polymer particles and at a temperature below the melting point of the powder particles. The energy input during the grinding is preferably low. A preferred polymer is PVDF. The invention furthermore relates to polymer/carbon nanotube mixtures which can be obtained by a method according to the invention, and to the use of such polymer/carbon nanotube mixtures for the production of electrodes.

Abstract: Use of physical vapor deposition methodologies to deposit nanoscale gold on activating support media makes the use of catalytically active gold dramatically easier and opens the door to significant improvements associated with developing, making, and using gold-based, catalytic systems. The present invention, therefore, relates to novel features, ingredients, and formulations of gold-based, heterogeneous catalyst systems generally comprising nanoscale gold deposited onto a nanoporous support.

Abstract: Methods for fabricating sublithographic, nanoscale microstructures arrays including openings and linear microchannels utilizing self-assembling block copolymers, and films and devices formed from these methods are provided. In some embodiments, the films can be used as a template or mask to etch openings in an underlying material layer.

Abstract: The present disclosure provides a method for a catalyst-free growth mode of defect-free Gallium Arsenide (GaAs)-based nanoneedles on silicon (Si) substrates with a complementary metal-oxide-semiconductor (CMOS)-compatible growth temperature of around 400° C. Each nanoneedle has a sharp 2 to 5 nanometer (nm) tip, a 600 nm wide base and a 4 micrometer (?m) length. Thus, the disclosed nanoneedles are substantially hexagonal needle-like crystal structures that assume a 6° to 9° tapered shape. The 600 nm wide base allows the typical micro-fabrication processes, such as optical lithography, to be applied. Therefore, nanoneedles are an ideal platform for the integration of optoelectronic devices on Si substrates. A nanoneedle avalanche photodiode (APD) grown on silicon is presented in this disclosure as a device application example. The APD attains a high current gain of 265 with only 8V bias.

Abstract: Methods for preparing ferroelectric nanoparticles, liquid crystal compositions containing the ferroelectric nanoparticles, and electronic devices utilizing the ferroelectric nanoparticles are described. The methods of preparing the ferroelectric nanoparticles may include size-reducing a starting material comprising particles of a bulk intrinsically nonferroelectric glass to form glass nanoparticles having an average size of less than 20 nm, the glass nanoparticles comprising ferroelectric nanoparticles. Exemplary bulk intrinsically nonferroelectric glasses may include borosilicate glasses, tellurite glasses, bismuthate glasses, gallate glasses, and mixtures thereof, for example. The size reduction may be accomplished using ball milling with a solvent combination such as n-heptane and oleic acid. Liquid crystal compositions may include the ferroelectric nanoparticles in combination with a liquid crystal.

Abstract: Graphene produced by media ball milling has very small particle size, a relatively high surface area and unique aspect ratios. It is uniquely suited to make nano-composites or coating by coating or admixing other particles. Metals or metal oxides can be coated or formed into composites with the high surface area, relatively low aspect ratio graphene. If the added particles are larger than the graphene, they are coated with graphene, and if they are about the same approximate size, a nano-composite forms. The nanocomposites are useful for producing electrodes, especially for battery and supercapacitor applications.

Abstract: Nano-scale particles of materials can be produced by vaporizing material and allowing the material to flow in a non-violently turbulent manner into thermal communication with a cooling fluid, thereby forming small particles of the material that can be in the nano-scale size range. A raw material feeder can be configured to feed raw material toward a heater which vaporizes the raw material. The feeder can include a metering device for controlling the flow of raw material toward the heater. A gas source can also be used to cause gas to flow through a portion of the raw material feeder along with the raw material.

Abstract: Methods for integrating the production of cellulose nanocrystals (CNC) and cellulose nanofibrils (CNF) from cellulose are provided. The methods use milder acid hydrolysis conditions than those for maximal CNC production to achieve reduced degradation of cellulose into soluble sugars. Also provided are negatively charged cellulosic solid residues (CSRs) in the form of cellulose fibers (CF) and/or cellulose microfibrils (CMF) during the acid hydrolysis, as well as CNFs fabricated from the CSRs.

Abstract: Disclosed are ordered mesoporous carbon-carbon nanotube nanocomposites and a method for manufacturing the same. The method for manufacturing ordered carbon-carbon nanotube nanocomposites according to the present invention includes: forming a mixture of a carbon precursor and ordered mesoporous silica; carbonizing the mixture to form a ordered mesoporous silica-carbon composite; and removing the mesoporous silica from the ordered mesoporous silica-carbon composite.

Abstract: A method of making ceramic articles includes compounding ceramic precursor batch components that include hydrous clay. The hydrous clay includes particle components having a platy geometry. The crystallite size of the platy hydrous clay particle components is less than a predetermined amount. Controlling such crystallite size can result in fired ceramic articles with a lower coefficient of thermal expansion and improved thermal shock resistance.

Abstract: The electrocatalyst for the electrochemical conversion of carbon dioxide includes a copper material supported on titania nanotubes. The copper material may be pure copper, copper and ruthenium, or copper and iron supported on the titania nanotubes. The electrocatalyst is prepared by first dissolving copper nitrate trihydrate in deionized water to form a salt solution. Titania nanotubes are then added to the salt solution to form a suspension, which is then heated. A urea solution is added to the suspension to form the electrocatalyst in solution. The electrocatalyst is then removed from the solution. In addition to dissolving the copper nitrate trihydrate in the volume of deionized water, either iron nitrate to monohydrate or ruthenium chloride may also be dissolved in the deionized water to form the salt solution.

Abstract: Composite materials having a multi-wall carbon nanotube content of from 4 to 15% by weight, based on total weight of the composite, are produced from a dispersion of multi-wall carbon nanotubes (MWCNTs) and a fiber reinforcing material in a carrier fluid which is processed to form a shaped article that may then be infused with a liquid polymer or polymer-forming mixture to form the composite.

Abstract: Monodisperse metal oxide nanopowders are prepared by treating a dispersion of crude metal oxide nanopowder with ultrasonication, allowing the dispersion to settle, and subjecting the remaining suspended portion to centrifugation to obtain a supernatant comprising metal oxide nanopowder.