摘要:
A method for synthesizing noble metal nanostructures is disclosed. The method involves reacting under heat a noble metal precursor, a polyol reducing agent, and a stabilizing polymer. Morphological control is achieved by controlling the reduction rate of the noble metal.
摘要:
A method for synthesizing noble metal nanostructures is disclosed. The method involves reacting under heat a noble metal precursor, a polyol reducing agent, and a stabilizing polymer. Morphological control is achieved by controlling the reduction rate of the noble metal.
摘要:
Chemically or biochemically active agents or other species are patterned on a substrate surface by providing a micromold having a contoured surface and forming, on a substrate surface, a chemically or biochemically active agent or fluid precursor of a structure. A chemically or biochemically active agent or fluid precursor also can be transferred from indentations in an applicator to a substrate surface. The substrate surface can be planar or non-planar. Fluid precursors of polymeric structures, inorganic ceramics and salts, and the like can be used to form patterned polymeric articles, inorganic salts and ceramics, reactive ion etch masks, etc. at the surface. The articles can be formed in a pattern including a portion having a lateral dimension of less than about 1 millimeter or smaller. The indentation pattern of the applicator can be used to transfer separate, distinct chemically or biochemically active agents or fluid precursors to separate, isolated regions of a substrate surface. Waveguide arrays, combinatorial chemical or biochemical libraries, etc. can be made. Differences in refractive index of waveguide and cladding can be created by subjecting the waveguide and cladding, made of identical prepolymeric material, to different polymerization or cross-linking conditions. Interferometers are defined by coupling arrays of waveguides, where coupling can be controlled by altering the difference in refractive index between cladding and waveguide at any desired location of the array. Alteration and refractive index can be created photochemically, chemically, or the like. Sensors also are disclosed, including biochemical sensors.
摘要:
In a method of generating a nanocrystal with a core-frame structure, a seed crystal, including a first substance, is exposed to a capping agent. The seed nanocrystal has a plurality of first portions that each has a first characteristic and a plurality of second portions that each has a second characteristic, different from the first characteristic. The capping agent has a tendency to adsorb to portions having the first characteristic and has a tendency not to adsorb to portions having the second characteristic. As a result, a selectively capped seed nanocrystal is generated. The selectively capped seed nanocrystal is exposed to a second substance that has a tendency to nucleate on the plurality of second portions and that does not have a tendency to nucleate on portions that have adsorbed the capping agent, thereby generating a frame structure from the plurality of second portions of the seed nanocrystal.
摘要:
A growth factor delivery scaffold combines a heparin/fibrin-based delivery system (HBDS) with a backbone based on polymer nanofibers for tissue (e.g., tendon and ligament) repair. The scaffold has improved surgical handling properties compared to the gelatinous consistency of the prior art HBDS system and retains the capability for delivering mesenchymal cells and controlling the release of growth factors. One application for the scaffold is mesenchymal stem cell (MSC) therapy for flexor tendon repair. The scaffold can deliver growth factors in a sustained manner, can be implanted for flexor tendon repair, is biocompatible, and is not cytotoxic. The growth factor delivery scaffold may also be used in the surgical repair of an injury to bone, muscle, cartilage, or other tissues.
摘要:
A catalyst material for use at elevated temperatures is provided. The material can include a plurality of fibers and a plurality of particles supported on the fibers. In addition, a porous layer can cover the plurality of particles and allow for process fluid to come into contact with the particles, and yet retard sintering of the particles at elevated temperatures is present. The plurality of fibers can be a plurality of nanofibers which may or may not be oxide nanofibers. The particles can be metallic nanoparticles and the porous layer can be a porous oxide layer.
摘要:
Methods for forming nanostructures of various shapes are disclosed. Nanocubes, nanowires, nanopyramids and multiply twinned particles of silver may by formed by combining a solution of silver nitrate in ethylene glycol with a solution of poly(vinyl pyrrolidone) in ethylene glycol. Hollow nanostructures may be formed by reacting a solution of solid nanostructures comprising one of a first metal and a first metal alloy with a metal salt that can be reduced by the first metal or first metal alloy. Nanostructures comprising a core with at least one nanoshell may be formed by plating a nanostructure and reacting the plating with a metal salt.
摘要:
Chemically or biochemically active agents or other species are patterned on a substrate surface by providing a micromold having a contoured surface and forming, on a substrate surface, a chemically or biochemically active agent or fluid precursor of a structure. A chemically or biochemically active agent or fluid precursor also can be transferred from indentations in an applicator to a substrate surface. The substrate surface can be planar or non-planar. Fluid precursors of polymeric structures, inorganic ceramics and salts, and the like can be used to form patterned polymeric articles, inorganic salts and ceramics, reactive ion etch masks, etc. at the surface. The articles can be formed in a pattern including a portion having a lateral dimension of less than about 1 millimeter or smaller. The indentation pattern of the applicator can be used to transfer separate, distinct chemically or biochemically active agents or fluid precursors to separate, isolated regions of a substrate surface. Waveguide arrays, combinatorial chemical or biochemical libraris, etc. can be made. Differences in refractive index of waveguide and cladding can be created by subjecting the waveguide and cladding, made of indentical prepolymeric material, to different polymerization or cross-linking conditions. Interferometers are defined by coupling arrays of waveguides, where coupling can be controlled by altering the difference in refractive index between cladding and waveguide at any desired location of the array. Alteration and refractive index can be created photochemically, chemically, or the like. Sensors also are disclosed, including biochemical sensors.
摘要:
Improved methods of forming a patterned self-assembled monolayer on a surface and derivative articles are provided. According to one method, an elastomeric stamp is deformed during and/or prior to using the stamp to print a self-assembled molecular monolayer on a surface. According to another method, during monolayer printing the surface is contacted with a liquid that is immiscible with the molecular monolayer-forming species to effect controlled reactive spreading of the monolayer on the surface. Methods of printing self-assembled molecular monolayers on nonplanar surfaces and derivative articles are provided, as are methods of etching surfaces patterned with self-assembled monolayers, including methods of etching silicon. Optical elements including flexible diffraction gratings, mirrors, and lenses are provided, as are methods for forming optical devices and other articles using lithographic molding. A method for controlling the shape of a liquid on the surface of an article is provided, involving applying the liquid to a self-assembled monolayer on the surface, and controlling the electrical potential of the surface.