Abstract: A structural support includes a cylindrical core, an inner layer within the core and an outer layer. The inner and outer layers include CNT-infused fiber materials in a thermoset matrix. A composite includes a thermoset matrix and a CNT-infused fiber material having CNTs with lengths between about 20 to about 500 microns or about 0.1 to about 15 microns. For the latter range, CNTs are present between about 0.1 to about 5 percent by weight of the composite. A method of making a structural support includes wet winding a first CNT-infused fiber about a cylindrical mandrel in a direction substantially parallel to the mandrel axis, wet winding a baseline layer about the first CNT-infused fiber at an angle substantially non-parallel to the mandrel axis, and wet winding a second CNT-infused fiber about the baseline layer in a direction substantially parallel to the mandrel axis.

Abstract: An electro-optic window is made of a material substantially transparent to infra-red radiation and is treated to have reduced RF transmission characteristics by the provision of carbon nanotubes within the window or on at least one, surface thereof.

Abstract: The present invention provides apparatus and methods for growing fullerene nanotube forests, and forming nanotube films, threads and composite structures therefrom. In some embodiments, an interior-flow substrate includes a porous surface and one or more interior passages that provide reactant gas to an interior portion of a densely packed nanotube forest as it is growing. In some embodiments, a continuous-growth furnace is provided that includes an access port for removing nanotube forests without cooling the furnace substantially. In other embodiments, a nanotube film can be pulled from the nanotube forest without removing the forest from the furnace. A nanotube film loom is described. An apparatus for building layers of nanotube films on a continuous web is described.

Abstract: Methods and systems for producing a change in a medium. A first method and system (1) place in a vicinity of the medium at least one upconverter including a gas for plasma ignition, with the upconverter being configured, upon exposure to initiation energy, to generate light for emission into the medium, and (2) apply the initiation energy from an energy source including the first wavelength ?1 to the medium, wherein the emitted light directly or indirectly produces the change in the medium. A second method and system (1) place in a vicinity of the medium an agent receptive to microwave radiation or radiofrequency radiation, and (2) apply as an initiation energy the microwave radiation or radiofrequency radiation by which the agent directly or indirectly generates emitted light in the infrared, visible, or ultraviolet range to produce at least one of physical and biological changes in the medium.

Abstract: Articles comprising neat, aligned carbon nanotubes and methods for production thereof are disclosed. The articles and methods comprise extrusion of a super acid solution of carbon nanotubes followed by removal of the super acid solvent. The articles may be processed by wet-jet wet spinning, dry-jet wet spinning, and coagulant co-flow extrusion techniques.

Abstract: Systems and methods for the extraction of carbon nanotubes (CNTs) by continuous and/or batch processing are disclosed. Generally, a carbon nanotube material including carbon nanotubes (CNTs), carbon nanoparticles (CNPs), and carboxylated carbon (CC) is provided and agitated to produce a well-dispersed mixture. The well-dispersed mixture can be allowed to stand in a vessel having a lower end and an upper end. In some cases, the CNPs settle at the lower end. In some cases, at least some of the CNTs and CC are disposed at the upper end and can be removed in a dispersion, which can be pH adjusted and/or filtered to extract the CNTs from the CC.

Abstract: This disclosure provides improved composite materials and methods for making the composite materials. Specifically, binder-free composite materials have been developed that have a network of CNTs in which one or more types of particles or fibers is embedded. The composite materials may be made by filtering suspensions containing carbon nanotubes, particles or fibers of interest, or both carbon nanotubes and particles or fibers of interest. The particles may be silicon particles, activated carbon particles, particles of a lithium compound, any other particles, or a combination thereof. The composite materials have a large number of applications, including electrical devices.

Abstract: A method is provided for producing germanium nanowires encapsulated within multi-walled carbon nanotubes. The method includes the steps of performing chemical vapor deposition using a combined germanium and carbon source having a general formula of GeR(4-x)Lx, where x=0, 1, 2, or 3; R is selected from a group consisting of alkyl, cycloalkyl or aryl and L=hydrogen, halide or alkoxide and growing germanium nanowires encapsulated within multi-walled carbon nanotubes on a substrate. A reaction product of that method or process is also provided.

Abstract: The present invention relates to articles for extracting a component from a fluid stream, the article including a body portion having a plurality of bores extending therethrough, the bores facilitating the flow of the fluid stream through the body portion in use, wherein the body portion is formed from a mixture of a binder and at least one component selected from the group consisting of carbon fibres, carbon nanotubes and mixtures thereof. The present invention also relates to a method of forming such articles and methods and systems including same.

Abstract: This invention relates generally to organized assemblies of carbon and non-carbon compounds and methods of making such organized structures. In preferred embodiments, the organized structures of the instant invention take the form of nanorods or their aggregate forms. More preferably, a nanorod is made up of a carbon nanotube filled, coated, or both filled and coated by a non-carbon material. This invention is further drawn to the separation of single-wall carbon nanotubes. In particular, it relates to the separation of semiconducting single-wall carbon nanotubes from conducting (or metallic) single-wall carbon nanotubes. It also relates to the separation of single-wall carbon nanotubes according to their chirality and/or diameter.

Abstract: Provided are fuser members and printing apparatuses including fuser members. The fuser member can include a substrate and a top coat layer including a hyper nanocomposite disposed over the substrate, wherein the hyper nanocomposite can include a plurality of nanoparticles substantially uniformly dispersed in one or more cross-linked hyperbranched polymers selected from the group consisting of polycarbosilane, polycarbosilixane, polycarbosilazene, and polyfluorocarbon.

Abstract: The present invention provides a composite material suitable for use in an anode for a lithium ion battery, the composite material comprising a layer of a lithium-alloying material on the walls of an aligned nanotubular base material. Preferably, the lithium-alloying material comprises a material selected from the group consisting of Si, Sn, Pb, Al, Au, Pt, Zn, Cd, Ag, Mg, and a combination of two or more of the foregoing.

Abstract: According to certain embodiments, an electro-magnetic radiation detector includes a sensor coupled to multiple nanostructures and an electro-magnetic radiation indicating device. The nanostructures are adapted to absorb electro-magnetic energy and generate heat according to the absorbed electro-magnetic energy. The sensor is adapted to measure the heat generated by the plurality of nanostructures and to generate a first signal according to the measured heat. The electro-magnetic radiation indicating device is operable to receive the signal from the sensor and indicate a level of electro-magnetic energy absorbed by the plurality of nanostructures according to the received signal.

Abstract: The present invention relates to design and development of carbon nanotubes (CNT) reinforced electrically conducting synthetic foams comprising resin matrix system, carbon nanotubes, hollow glass microspheres and optionally hardener or catalyst for electrical conductivity and related applications especially electromagnetic interference (EMI) shielding.

Abstract: The application generally describes devices, systems, and methods for determination of one or more analytes. Embodiments described herein may be useful as sensors for analytes such as explosives, chemical warfare agents, and/or toxins. In some cases, chemiresistor or chemFET sensor devices for monitoring volatile organics, especially chemical warfare agents such as sarin, are described. Some embodiments comprise functionalised carbon nanotube/conjugated polymer composites (6) as sensing material. In some embodiments, the polymer is poly(3-hexylthiophene), 3PHT, optionally substituted with calixarenes, or hexafluoroisopropanol susbstituted polythiophene, HFIP-PT. Biosensing embodiments are also described, as well as methods of manufacturing the devices.

Abstract: A fuel cell of the present invention comprises a cathode and an anode, one or both of the anode and the cathode including a catalyst comprising a bundle of longitudinally aligned graphitic carbon nanotubes including a catalytically active transition metal incorporated longitudinally and atomically distributed throughout the graphitic carbon walls of said nanotubes. The nanotubes also include nitrogen atoms and/or ions chemically bonded to the graphitic carbon and to the transition metal. Preferably, the transition metal comprises at least one metal selected from the group consisting of Fe, Co, Ni, Mn, and Cr.

Abstract: Disclosed herein is a method of manufacturing an electrode substrate, by which a film-shape electrode substrate including a carbon nanotube layer, which does not include a dispersant, is not related to the kind of binder and is strongly attached to the electrode substrate, can be easily manufactured.

Abstract: Growing spin-capable multi-walled carbon nanotube (MWCNT) forests in a repeatable fashion will become possible through understanding the critical factors affecting the forest growth. Here we show that the spinning capability depends on the alignment of adjacent MWCNTs in the forest which in turn results from the synergistic combination of a high areal density of MWCNTs and short distance between the MWCNTs. This can be realized by starting with both the proper Fe nanoparticle size and density which strongly depend on the sheet resistance of the catalyst film. Simple measurement of the sheet resistance can allow one to reliably predict the growth of spin-capable forests. The properties of pulled MWCNTs sheets reflect that there is a relationship between their electrical resistance and optical transmittance. Overlaying either 3, 5, or 10 sheets pulled out from a single forest produces much more repeatable characteristics.

Abstract: The invention provides a carbon nanotube compound and method for producing the same. The method of the invention comprises the following steps. Firstly, Aniline-trimer and DMAc (dimethyl acetamide) solution are mixed to form a first solution. Secondly, Dianhydride and DMAc solution are mixed to form a second solution. The first solution and the second are mixed to form a third solution. Additionally, carboxyl-multiwall carbon nanotubes (c-MWNT), Diaminodiphenylether and DMAc solution are mixed to form a fourth solution. The third solution and the fourth are mixed to form a polyamic acid/CNT solution. Some polyamic acid/CNT solution is spread on a substrate and processed by a thermal treatment, and a carbon nanotube compound is eventually produced.

Abstract: A carbon nanotube filter. The filter including a filter housing; and chemically active carbon nanotubes within the filter housing, the chemically active carbon nanotubes comprising a chemically active layer formed on carbon nanotubes or comprising chemically reactive groups on sidewalls of the carbon nanotubes; and media containing the chemically active carbon nanotubes.

Abstract: A new method for preparing a supported catalyst is herein provided. The supported catalyst comprises a carbon nanotube network structure containing metal catalysts. The metal catalyst may be loaded onto functionalized carbon nanotubes before forming the carbon nanotube network structure. Alternatively, the metal catalyst may be loaded onto the carbon nanotube network structures themselves.

Abstract: The present invention relates to a catalyst system for the selective conversion of hydrocarbons into multi-walled carbon nanotubes and hydrogen comprising a compound of the formula: (Ni,Co)FeyOz(Al2O3)w wherein ‘y’ represents the molar fraction of Fe relative to Co and Ni and wherein 0.11?y?9.0, 1.12?z?14.5, and 1.5?w?64.

Abstract: Polymer coated carbon nanotube (NT) particles having NT particles with a solid polymer layer around the surface of each NT particle are presented. The NT particles can be isolated NTs or can include bundles of NTs. A method for preparation of the polymer coated carbon NT particles involves an aqueous dispersion that has a water insoluble first monomer contained in an emulsion-like nano-environment about the NT particles that undergoes an interfacial polymerization with a water soluble second monomer added to the dispersion.

Abstract: A high power density photo-electronic and photo-voltaic material comprising a bio-inorganic nanophotoelectronic material with a photosynthetic reaction center protein encapsulated inside a multi-wall carbon nanotube or nanotube array. The array can be on an electrode. The photosynthetic reaction center protein can be immobilized on the electrode surface and the protein molecules can have the same orientation. A method of making a high power density photo-electronic and photo-voltaic material comprising the steps of immobilizing a bio-inorganic nanophotoelectronic material with a photosynthetic reaction center protein inside a carbon nanotube, wherein the immobilizing is by passive diffusion, wherein the immobilizing can include using an organic linker.

Abstract: A tunable nanoscale resonator has potential applications in precise mass, force, position, and frequency measurement. One embodiment of this device consists of a specially prepared multiwalled carbon nanotube (MWNT) suspended between a metal electrode and a mobile, piezoelectrically controlled contact. By harnessing a unique telescoping ability of MWNTs, one may controllably slide an inner nanotube core from its outer nanotube casing, effectively changing its length and thereby changing the tuning of its resonance frequency. Resonant energy transfer may be used with a nanoresonator to detect molecules at a specific target oscillation frequency, without the use of a chemical label, to provide label-free chemical species detection.

Abstract: According to one embodiment, a nonvolatile memory device includes a memory cell. The memory cell is connected to a first interconnection and a second interconnection and includes a plurality of layers. The plurality of layers includes a memory layer and a carbon nanotube-containing layer which is in contact with the memory layer and contains a plurality of carbon nanotubes.

Abstract: A radiation-emitting device includes a nanowire that is structurally and electrically coupled to a first electrode and a second electrode. The nanowire includes a double-heterostructure semiconductor device configured to emit electromagnetic radiation when a voltage is applied between the electrodes. A device includes a nanowire having an active longitudinal segment selectively disposed at a predetermined location within a resonant cavity that is configured to resonate at least one wavelength of electromagnetic radiation emitted by the segment within a range extending from about 300 nanometers to about 2,000 nanometers. Active nanoparticles are precisely positioned in resonant cavities by growing segments of nanowires at known growth rates for selected amounts of time.

Abstract: Nanotube-based switching elements and logic circuits are disclosed. Under one embodiment of the invention, a Boolean logic circuit includes at least one input terminal and an output terminal, and a network of nanotube switching elements electrically disposed between said at least one input terminal and said output terminal. The network of nanotube switching elements effectuates a Boolean function transformation of Boolean signals on said at least one input terminal. The Boolean function transformation includes a Boolean inversion within the function, such as a NOT or NOR function.

Abstract: A nanostructured composite electrode is provided that includes a pair of conductive metal foils and a multiplicity of ordered nanostructures formed on each conductive metal foil. The ordered nanostructures include functionalized carbon multi-walled nanotubes electrophoretically deposited onto the metal foils. The ordered nanostructures also include synthesized nanoparticles electrophoretically deposited onto each of the carbon multi-walled nanotubes and the metal foils in proportion to the concentration of the carbon multi-walled nanotubes while in a stable colloidal suspension with the synthesized nanoparticles during electrophoretic deposition.

Abstract: A UV curable intermediate transfer media, such as a belt, that includes a first supporting substrate, such as a polyimide substrate layer, and a second surface layer of a carbon nanotube.

Abstract: The present invention relates to a nanocapsule-type structure having an average particle diameter of 1 to 50 nm, said nanocapsule-type structure comprising an aqueous solution of a metal compound encapsulated in the inside thereof. Preferably, the nanocapsule-type structure is such that the nanocapsule structure is formed by self-organization of a surfactant in an organic solvent. This nanocapsule structure is in a nanometer size, and high in dispersibility even in a high-concentration region in an organic solvent, and does not undergo aggregation, and it is useful as a catalyst for a CVD method.

Abstract: A two terminal memory device includes first and second conductive terminals and a nanotube article. The article has at least one nanotube, and overlaps at least a portion of each of the first and second terminals. The device also includes stimulus circuitry in electrical communication with at least one of the first and second terminals. The circuit is capable of applying first and second electrical stimuli to at least one of the first and second terminal(s) to change the relative resistance of the device between the first and second terminals between a relatively high resistance and a relatively low resistance. The relatively high resistance between the first and second terminals corresponds to a first state of the device, and the relatively low resistance between the first and second terminals corresponds to a second state of the device.

Abstract: Nanofiber adhesives and their uses with device, such as medical devices, are described. In one embodiment, a nanofiber adhesive layer may be disposed on a surface of a medical device, such as a backing layer of a sensor, for adhesion to a substrate. The nanofiber adhesive layer may allow durable adhesion to the substrate. Other described features may include materials and methods to determine the attachment of the medical device to a patient by determining the adhesive state of the adhesive layer.

Abstract: The present invention provides composite organics and optoelectronic devices, including photovoltaic devices, comprising the same. In one embodiment, the present invention provides a photovoltaic cell comprising a radiation transmissive first electrode, a photosensitive layer electrically connected to the first electrode, the photosensitive layer comprising a plurality of composite organic layers, wherein each of the plurality of composite organic layers comprises a polymeric phase and a nanoparticle phase, the nanoparticle phase comprising at least one exaggerated nanocrystalline grain.

Abstract: Systems and methods related to handling and/or isolating nanotubes and other nanostructures are generally described. In some embodiments, a polymer can be exposed to a collection of agglomerated nanostructures to produce individuated nanostructures. The polymer can comprise one or more pendant groups capable of participating in a pi-pi interaction with at least a portion of the agglomerated nanostructures to produce individuated nanostructures. Individuated nanostructures can be isolated from nanostructures that remain agglomerated. In some cases, individuated nanostructures can be freeze dried to provide, for example, a plurality of nanostructures in solid form. The systems and methods described herein may be so effective in maintaining separation between individuated nanostructures that pluralities of dried nanostructures can be re-suspended in a fluid after they are dried, in some cases with relatively low forces applied during re-suspension.

Abstract: Provided is a fibrous columnar structure aggregate having excellent mechanical properties, a high specific surface area, and excellent pressure-sensitive adhesive property. Provided is a fibrous columnar structure aggregate having excellent heat resistance, a high specific surface area, and excellent pressure-sensitive adhesive properties under temperature conditions ranging from room temperature to a high temperature. Provided is a fibrous columnar structure aggregate having a high specific surface area and such pressure-sensitive adhesive property that its adhesive strength for adherends different from each other in surface free energy does not change (the aggregate is free of adherend selectivity). Provided is a pressure-sensitive adhesive member using any such fibrous columnar structure aggregate.

Abstract: A method for producing a conductive composite includes coating a composition (B) containing a dispersing agent (A) having a hydroxyl group in the molecule and a conductive material on a substrate, and coating a liquid containing a compound (C) represented by the formula (I) below and/or a hydrolysate of the compound (C) on a surface coated with the composition (B): (R1)mMXn-m ??(1).

Abstract: A method for preparing hollow nanofibers having carbon as a primary component by contacting a carbon-containing compound with a catalyst at 500 to 1200° C., wherein the catalyst is one of a zeolite exhibiting thermal resistance at 900° C. and, supported thereon, a metal; a metallosilicate zeolite containing a heteroatom except aluminum and silicon and a metal; a supporting material and fine cobalt particles exhibiting a binding energy of a cobalt 2P3/2 electron of 779.3 to 781.0 eV; a supporting material and fine cobalt particles exhibiting a cobalt atom ratio in the surface of the supporting material of 0.1 to 1.5%, as measured by the X-ray photoelectron spectroscopy at 10 kV and 18 mA; a supporting material and fine cobalt particles exhibiting a weight ratio of cobalt to a second metal component of 2.5 or more; and a zeolite having a film form and a metal.

Abstract: A method for separating carbon nanotubes is disclosed where nanotubes with specific properties are separated from a mixture of nanotube products, which contains various types of nanotubes and impurities.

Abstract: A multi-wall carbon nanotube field emitter and method of producing the same is disclosed. The multi-wall carbon nanotube field emitter comprises a nanotube having a diameter between approximately 1 nanometer and approximately 100 nanometers with an integrally attached outer layer of graphitic material that is approximately 1 micrometer to approximately 10 micrometers in diameter attached to an etched tip of a wire. The tip of the wire is etched to form a tip and a slot is fabricated in the tip for alignment and attachment of the carbon nanotube. A focus ion beam is used to weld the nanotube to the tungsten tip for electron field emission applications.

Abstract: This invention relates to a method of obtaining vinyl alcohol homo- or copolymer-based conductive composite fibres with a high proportion of nanotubes, particularly carbon nanotubes, which are capable of ensuring thermal and/or electric conduction. It likewise relates to the conductive composite fibres obtainable by this method as well as the uses thereof.

Abstract: A system is provided for forming carbon nanotubes comprising growing carbon nanotubes using a hot filament CVD system.

Abstract: This invention concerns a polymer coating material composition (PCM) comprising as components a polymer matrix, carbon nanotubes (CNT) as optical power limiters (OPL), and carbon rich molecules. One aspect of the invention is where the Polymer Matrix is a hyperbranched polymer, such as a hyperbranched polycarbosiloxane polymer. Another aspect of the invention is where the CNT is a short multiwall carbon nanotube (sMWNT). A further aspect of the invention is where the carbon-rich molecules are triethoxysilyl anthracene derivatives. The composition wherein the ratio in weight percent of Polymer Matrix to CNT to carbon-rich molecule is from 94:3:3 to 99.8:0.1:0.1. The composition can further contain one or more of multi-photon absorbers (MPA) chromophores or reverse saturable absorbers (RSA) chromophores. These compositions can be used as: a) a film, b) a coating, c) a liquid, d) a solution, or e) a sandwiched film between two transparent substrates.

Abstract: The present invention relates to compositions of a nanofluid, which comprises a thermal transfer fluid and carbon nanoparticles. The nanofluid may be hydrophilic nanofluids, such as a coolant, or hydrophobic nanofluids, such as nanolubricants or nanogreases. In particular, the present invention provides a homogenous hydrophilic nanofluid, which contains soluble carbon nanotubes in the hydrophilic thermal transfer fluid. The present invention also provides a nanogrease, which is a sustainable dispersion of solid carbon nanotubes in a hydrophobic thermal transfer fluid. The solid carbon nanotubes function as both as a thickener to modulate viscosity and as a solid heat transfer medium to enhance thermal conductivity and high temperature resistance.

Abstract: The present invention discloses a dispersant for carbon nanotubes having excellent dispersion ability and to a carbon nanotube composition including the dispersant. In the dispersant, the heads and tails of the dispersant are regioregularly arranged in one direction, and the structural properties of the dispersant are controlled such that the ratio of heads to tails is 1 or more, thereby effectively stabilizing and dispersing carbon nanotubes in various dispersion media, such as an organic solvent, water, a mixture thereof and the like, compared to conventional dispersants.

Abstract: A single wall carbon nanotube (SWCNT) film electrode (FE), all-organic electroactive device systems fabricated with the SWNT-FE, and methods for making same. The SWCNT can be replaced by multi-wall carbon nanotubes or few wall carbon nanotubes. The SWCNT film can be obtained by filtering SWCNT solution onto the surface of an anodized alumina membrane. A freestanding flexible SWCNT film can be collected by breaking up this brittle membrane. The conductivity of this SWCNT film can advantageously be higher than 280 S/cm. The EAP actuator layered with the SWNT-FE shows a higher electric field-induced strain than an EAP layered with metal electrodes because the flexible SWNT-FE relieves the restraint of the displacement of the polymeric active layer as compared to the metal electrode. In addition, if thin enough, the SWNT-FE is transparent in the visible light range, thus making it suitable for use in actuators used in optical devices.

Abstract: The present invention relates to compositions of a nanofluid, which comprises a thermal transfer fluid and carbon nanoparticles. The nanofluid may be hydrophilic nanofluids, such as a coolant, or hydrophobic nanofluids, such as nanolubricants or nanogreases. In particular, the present invention provides a homogenous hydrophilic nanofluid, which contains soluble carbon nanotubes in the hydrophilic thermal transfer fluid. The present invention also provides a nanogrease, which is a sustainable dispersion of solid carbon nanotubes in a hydrophobic thermal transfer fluid. The solid carbon nanotubes function as both as a thickener to modulate viscosity and as a solid heat transfer medium to enhance thermal conductivity and high temperature resistance.

Abstract: Processes for preparing reinforced polymeric material and the materials formed therefrom are discussed herein. The processes generally include providing a polymeric matrix, providing single-wall carbon nanotubes (SWNT) or multiple-wall carbon nanotubes (MWNT), purifying by the nanotubes in a single step of dissolving a support and catalyst particles with an agent appropriate to the nature of the support to form a purified support, functionalising the purified support by reaction with an alkylamine to form a functionalized support, dispersing the nanotubes in the polymeric matrix by mixing in the molten state to form a mixture and optionally orienting the mixture by stretching.

Abstract: A nanoscale nanocrystal which may be used as a reciprocating motor is provided, comprising a substrate having an energy differential across it, e.g. an electrical connection to a voltage source at a proximal end; an atom reservoir on the substrate distal to the electrical connection; a nanoparticle ram on the substrate distal to the atom reservoir; a nanolever contacting the nanoparticle ram and having an electrical connection to a voltage source, whereby a voltage applied between the electrical connections on the substrate and the nanolever causes movement of atoms between the reservoir and the ram. Movement of the ram causes movement of the nanolever relative to the substrate. The substrate and nanolever preferably comprise multiwalled carbon nanotubes (MWNTs) and the atom reservoir and nanoparticle ram are preferably metal (e.g. indium) deposited as small particles on the MWNTs.

Abstract: The present invention provides nanocomposite materials comprising carbon nanotubes and oligo(p-phenylenevinylene) (OPV). Dispersion of CNT in the solution of solution of oligo(p-phenylenevinylene) (OPV) in organic solvent results in the formation of nanocomposite material. The ?-? interaction between CNT and OPV molecule were shown by spectroscopic and microscopic techniques. The nanocomposite solution can be drop casted over glass or metallic surface for the preparation of superhydrophobic coating. The resultant composite surface shows superhydrophobic nature even with corrosive liquids and its contact angle is almost constant even after prolonged contact with water.