1/29/11
An introduction to the study of alternative energy sources. Researches use ground-breaking atomic imaging techniques to view hydrogen atoms moving on a specialized surface.
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Nanotechnology could provide the answer in the form of a new kind of solar cell, one which would be relatively inexpensive to manufacture and highly flexible in design. In fact, you maybe surprised as to just how flexible these cells might be! Find out more by watching this video.
Barium Titanate belongs to the family of complex oxide pervoskites possessing the ferroelectric property have far reaching applications in the electronics industry, as transducers and actuators having piezoelectric effect, high-K dielectric capacitors and in memory applications. Barium titanate is one of the most important dielectric materials widely used for multilayer ceramic capacitors (MLCCs) and future nano-electronics. Barium titanate/glass nanocomposite capacitors have great future in energy storage applications.
Properties
Barium titanate nanoparticles, nanopowder, nanodots or nanocrystals are spherical or faceted high surface area nanocrystalline alloy particles with magnetic properties. Nanoscale barium titanate particles are typically 20-40 nanometers (nm) with specific surface area (SSA) in the 30 – 50 m 2 /g range and also available in an average particle size of 100 nm range with a specific surface area of approximately 7 m 2 /g. Nano barium titanate particles are also available in ultra high purity and as coated and dispersed forms.
Preparation of BaTiO3
For the preparation of BaTiO3 nanocrystals, nanowires and nanotubes various synthesis methods are used. They include hydrothermal/ solvothermal synthesis, co precipitation and sol-gel processing, pyrolysis and decomposition of bimetallic alkoxide precursors in the presence of coordinating ligands, liquid-solid-solution (LSS) phase transfer, peptide templates assisted room temperature synthesis, low temperature aqueous synthesis with seed-mediated growth method, and sol-precipitation route. But sol-gel processing and other traditional methods of producing colloids of nanoscale barium titanate often produce particles with broad size distributions and high tendencies toward aggregation.
For BaTiO3 nanocrystal synthesis, a single bimetallic molecular precursor is used to ensure a correct stoichiometry of the product. The BaTi precursor barium titanium glycolate BaTiC2H4O234C2H6O2H2O is first prepared in a dry box by mixing BaO, ethylene glycol, 2-propanol, and TiOPr4. The resulting white powder is filtered, washed, dried at 60 °C and kept in dry box because of its hygroscopic property.
For BaTiO3 nanocrystal synthesis, a single bimetallic molecular precursor is used to ensure a correct stoichiometry of the product. The BaTi precursor barium titanium glycolate BaTiC2H4O234C2H6O2H2O is first prepared in a dry box by mixing BaO, ethylene glycol, 2-propanol, and TiOPr4. The resulting white powder is filtered, washed, dried at 60 °C and kept in dry box because of its hygroscopic property.
Improved method
Researcher Huang and others of Columbia University report an improved method. The improved method is done by the nucleation controlled thermal decomposition of BaTi molecular precursor in the presence of oleic acid followed by further crystallization at higher temperature. The resulting BaTi oxide nanoparticles can be redispersed in hexane and have uniform BaTiO3 nanocrystals in the form of isolated nanocrystals and continuous and micro patterned thin films can be produced by spin coating or soft lithography micro printing or micro molding.
1/28/11
Nanoparticles synthesis is done by two major routes, which include classical synthesis and green synthesis. The green synthesis techniques generally utilize relatively non-toxic chemicals non-toxic solvents, biological extracts and systems. Biological methods are considered safe and ecologically sound for the nanomaterial fabrication as an alternative to conventional physical and chemical methods.Nanoparticles
Gold, silver, and copper have been used mostly for the synthesis of stable dispersions of nanoparticles, which are useful in areas of photography, catalysis, biological labeling, photonics, optoelectronics and surface-enhanced Raman scattering (SERS) detection.
Biological route
Biological routes to the synthesis of these particles have been proposed by exploiting microorganisms and by vascular plants. The functions of these materials depend on their composition and structure. Plants have been reported to be used for synthesis of metal nanoparticles of gold and silver and of a gold-silver-copper alloy. Of this colloidal silver is of particular interest because of its distinctive properties such as good conductivity, chemical stability, and catalytic and antibacterial activity.
Biomolecules
Researchers report that biomolecules like protein, phenols and flavonoids not only play a role in reducing the ions to the nanosize, but also play an important role in the capping of the nanoparticles. The reduction of Ag+ ions by combinations of biomolecules found in these extracts such as vitamins, enzymes/proteins, organic acids such as citrates, amino acids, and polysaccharides is environmentally benign, yet chemically complex.
Mechanism
The mechanism for the reduction of Ag ions to silver could be due to the presence of water-soluble antioxidative substances like ascorbate. This acid is present at high levels in all parts of plants. Ascorbic acid is a reducing agent and can reduce, and thereby neutralize, reactive oxygen species leading to the formation of ascorbate radical and an electron. This free electron reduces the Ag+ ion to Ag0.
It has been reported that ionic silver strongly interacts with thiol group of vital enzymes and inactivates them. Experimental evidence suggests that DNA loses its replication ability once the bacteria have been treated with silver ions. The antibacterial effect of nanoparticles can be attributed to their stability in the medium as a colloid, which modulates the phosphotyrosine profile of the bacterial proteins and arrests bacterial growth.
Synthesis from herb
Indian researchers at Patna University have biosynthesised silver nanoparticles from Desmodium triflorum. Desmodium triflorum is a wild much branched slender diffused herb with trifoliate leaves occurring as small under herb found in grasslands, fields, and agricultural lands forming a green turf on the ground. The dry plant was powdered, added with distilled water, heated and the extract was added to AgNO3 solutions. The bioreduction of Ag+ ions took place . The solution containing the signatory color of AgNPs (dark brown) was dryed in oven to get powders of silver nanoparticles. Thus stable and spherically shaped nanoparticles of average size ~10nm were synthesized using desmodium plant. The green synthesis of AgNPs fulfills all the three main steps, which must be evaluated based on green chemistry perspectives, including selection of solvent medium, selection of environmentally benign reducing agent and selection of nontoxic substances for the AgNPs stability. The study further showed that Ag nanoparticles presented good antibacterial performance against common pathogens. The nanoparticles when combined with the antibiotics show synergic effect in suppressing growth of antibiotics.
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1/27/11
Quantum dots (QDs), also known as semi conducting nanoparticles, are promising zero‐dimensional advanced materials because of their nanoscale size and because they can be engineered to suit particular applications. Quantum dots are nanosized semi conductors that generate electron-hole pairs confined in all three dimensions (quantum confinement) and hence behave like giant molecules rather than bulk semiconductors. Often referred to as artificial atoms, quantum dots range in size from 2-10 nanometers in diameter. While typically composed of several thousand atoms, all the atoms are shared and coordinated as if there is only one atomic nucleus at the centre. That property enables numerous revolutionary schemes for electronic devices. The single atom quantum dots have also demonstrated significant control over individual electrons by using very little energy which is the key to quantum dot application in entirely new forms of silicon-based electronic devices, such as ultra low power computers. QD applications
Quantum dots find applications in light emitting diodes, transistors, solar cells, drug delivery, cancer therapy, cell imaging, made to fluoresce in different colors depending on their size, superb carrier and last much longer than conventional dyes when used to tag molecules, and usually stop emitting light in seconds. Researchers are using QDs in medicine, cell and molecular biology and working to develop nanocrystal quantum-dot-based lasers, amplifiers and biological sensors capable of detecting cancer. QD is used as nonlinear optical devices (NLO), electro‐optical devices, in computing applications and as single-photon emitters. QDs can be joined to polymers in order to produce nanocomposites which can be considered a scientific revolution of the 21st century. semiconductor QDs can be conjugated with biomolecules to produce a new class of markers and probes that have affinities for binding with selected biological structures.
QDs do not scatter light at visible or longer wavelengths and hence minimize optical losses in practical applications, quantum confinement and surface effects become very important and therefore manipulation of the dot diameter or modification of its surface allows the properties of the dot to be controlled. Quantum confinement affects the absorption and emission of photons from the dot.
Studies of semiconductor devices utilizing quantum dots are vigorous, such as quantum dot memory devices utilizing the hole burning effects. Quantum dots can be incorporated into solar-cell devices in many different ways.
Techniques are known which artificially form quantum dots by using fine patterning technologies. When a quantum dot is positioned in close vicinity with a plasmonic nanostructure, the electric field enhancement will strongly enhance the QD optical cross section and modify its radiative lifetime.
Limitation
Limitation
Quantum dots interact with a solid-state environment, necessitating cryogenic operation temperatures, and yet environment-induced decoherence, but this can be offset by being fixed in place with large dipole moments and integrated into monolithic optical micro cavity structures.
Most quantum dots contain highly toxic metals such as cadmium, which tends to be released when the quantum dots enter the cells or organisms. In one study, CdTe quantum dots coated with hydrophilic sodium thioglycolate caused disruption in a cultured monolayer of Caco-2 human intestinal cells and cell-death at 0.1 ppm, which was thought to be caused by the quantum dots, rather than cadmium.
In another study, CdSe/ZnS quantum dots injected intravenously into mice caused marked vascular thrombosis in the lungs at 0.7 to 3.6 nanomol per mouse, especially when the quantum dots had carboxylate surface groups.
Most quantum dots contain highly toxic metals such as cadmium, which tends to be released when the quantum dots enter the cells or organisms. In one study, CdTe quantum dots coated with hydrophilic sodium thioglycolate caused disruption in a cultured monolayer of Caco-2 human intestinal cells and cell-death at 0.1 ppm, which was thought to be caused by the quantum dots, rather than cadmium.
In another study, CdSe/ZnS quantum dots injected intravenously into mice caused marked vascular thrombosis in the lungs at 0.7 to 3.6 nanomol per mouse, especially when the quantum dots had carboxylate surface groups.
Researchers claim that quantum dots activated the coagulation cascade through contact. In fact, many kinds of nanoparticles enhance the formation of insoluble fibrous protein aggregates (amyloids), which are associated with human diseases including Alzheimer’s, Parkinson’s and Creutzfeld-Jacob disease.
Structure
Structure
Quantum dot structures have drawn attention as the ultimate structure based upon quantum mechanics. A quantum dot is an ultra fine structure having an energy level lower than a potential of a nearby region and being able to three dimensionally confine carriers in an ultra fine region. Only two electrons can exist in one quantum dot at the ground level on the conduction band side. If a quantum dot is used as an active region of a laser device, interaction between electrons and holes can be made efficient. A laser device using quantum dots is expected to be a device which exceeds the limit of laser devices using a two dimensionally extending quantum well layer, from the viewpoint of an oscillation threshold value, the temperature characteristics of the oscillation threshold value and the like.
Fabrication
Quantum dots can be formed by various methods such as lithography with electron beams; a method of disposing quantum dots on vertices of pyramid crystals stacked on a mask pattern, a method of disposing quantum dots on vertices of quadrilateral pyramids formed under a mask pattern; a method utilizing initial lateral growth of crystals on a slanted substrate; a method utilizing atom manipulation based upon STM (scanning tunneling microscopy); and the like. These methods have the common aspect that semiconductor materials are artificially processed. These methods are therefore advantageous in that the position of each quantum dot can be controlled freely.
Self-organization
Another method of forming quantum dots is by self-organization. Specifically, a semiconductor layer is formed through vapor phase epitaxial growth under the specific conditions of lattice mismatch. In this case, not a film which two-dimensionally and uniformly extends on an underlying surface but a three dimensional fine structure (quantum dot structure) is formed by itself. With this method, as compared to artificial fine patterning, a quantum dot structure can be formed in which quantum dots are distributed at a higher density and each quantum dot has a high quality.
SK mode
The best known one of self-organization of quantum dots is the Stranski-Krastanov mode (SK mode). During the growth in the SK mode, a two dimensionally extending thin film (wetting layer) is grown initially on an underlying surface, and as source material continues to be supplied, quantum dots are formed by themselves. The quantum dots formed in the SK mode are buried in a quantum well layer so that the wavelength of luminescence of quantum dots can be controlled. Quantum dots having a uniform size can be formed by the SK mode.
Deposition method
The quantum dot deposition method used by Hwang and his colleagues is typical but, ultimately, random. A layer of fairly uniform thickness can be obtained using spin-coating techniques, for example, but it is no way to get a finely arranged array of particles with submicron resolution between particles.
The ability to precisely lay down individual quantum dots could be the next step toward improved biosensors, but also to better LEDs, organic LEDs, solar panels and other optoelectronics.
But it’s not easy as one must create the particles, and then move them around individually to the desired location. Doing this with optical tweezers would be direct, but besides other challenges, would be dreadfully slow when spacing out an array of particles on a commercial scale.
Instead, placing arrangements of quantum dots has typically been done through photochemical means. One such method is to deposit quantum dots with molecular tags, or ligands, that adhere the particles onto a substrate, then, with lasers, chemicals or both, strip the bonds of select adherents, leaving only the quantum dots required.
Lithosynthesis
Researchers at Texas A&M University have developed a method named litho synthesis that takes advantage of the photo-oxidation process. Litho synthesis is a process wherein CdSe quantum dots are capped with a photo-oxidizable molecule, then spread onto a positively charged glass, silicon or other substrate. When a laser scans the layered surface, a portion of the caps are broken, leaving behind patterned arrays of quantum dots that have various emission intensities and wavelengths.
Ion beam scanner
Another method is provided for forming quantum holes of nanometer levels. In an ion beam scanner, ions are projected from an ion gun onto a semiconductor substrate. During the projection, ions are focused into an ion beam whose focal point is controlled to determine the diameter of the ion beam, and the ion beam is accelerated. When being incident upon the semiconductor substrate, the ion beam is deflected so as to form a plurality of quantum holes. Also provided is a semiconductor for use in a light emitting device with quantum dots. Impurities are doped onto a semiconductor substrate to form a P-type semiconductor layer on which an undoped, intrinsic semiconductor is grown to a certain thickness. A plurality of quantum holes are provided for the intrinsic semiconductor layer followed by filling materials smaller in energy band gap than the intrinsic semiconductor in annealed quantum holes through recrystallization growth. Next, an N-type semiconductor layer is overlaid on the quantum hole layer. Composition of the materials filled in the quantum holes determines the color of the light emitted from the semiconductor for use in a light emitting device.
Thus, the semiconductor is fabricated to emit light of the three primary colors or one of them. By cutting the semiconductor, unit display panels or elements can be prepared which emit radiation at wavelengths corresponding to red, green and blue colors.
Another method is provided for forming quantum holes of nanometer levels. In an ion beam scanner, ions are projected from an ion gun onto a semiconductor substrate. During the projection, ions are focused into an ion beam whose focal point is controlled to determine the diameter of the ion beam, and the ion beam is accelerated. When being incident upon the semiconductor substrate, the ion beam is deflected so as to form a plurality of quantum holes. Also provided is a semiconductor for use in a light emitting device with quantum dots. Impurities are doped onto a semiconductor substrate to form a P-type semiconductor layer on which an undoped, intrinsic semiconductor is grown to a certain thickness. A plurality of quantum holes are provided for the intrinsic semiconductor layer followed by filling materials smaller in energy band gap than the intrinsic semiconductor in annealed quantum holes through recrystallization growth. Next, an N-type semiconductor layer is overlaid on the quantum hole layer. Composition of the materials filled in the quantum holes determines the color of the light emitted from the semiconductor for use in a light emitting device.
Thus, the semiconductor is fabricated to emit light of the three primary colors or one of them. By cutting the semiconductor, unit display panels or elements can be prepared which emit radiation at wavelengths corresponding to red, green and blue colors.
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1/25/11
Nanotechnology is an up coming area of study not only in physics and chemistry but also in the field of biology. In view of the marvelous use of nanotechnology, scientists carry out research in this most vital discipline. The applications nanomaterials are numerous and include catalysis, optical devices, electronics, sensors, environmental remediation, medical, and the list is continually growing. For example, silver and gold nanoparticles can potentially be used in various human contacting areas such as cosmetics, foods and medical applications.Synthesis routes
In terms of synthesis there are two major routes, which include classical synthesis and green synthesis. The classical synthetic routes are well defined in the literature. However, newer environmentally conscious synthetic routes are being developed every day. The green synthesis techniques generally utilize relatively non-toxic chemicals to synthesize nanomaterials, and include the use of non-toxic solvents (such as water), biological extracts, biological systems, and microwave assisted synthesis.
Plant extracts
Biologic synthesis of nanoparticles using plant extracts is at present under exploitation by researcher workers. The utilisation of Azadirachta indica (Neem), Medicago sativa (Alfalfa), Aloe vera, Emblica officinalis (amla, Indian Gooseberry) and microorganisms for the production of nanoparticles has been reported in the literature. The polyol components and the water-soluble heterocyclic components are largely accountable for the reduction of Ag ions and the stabilization of the nanoparticles. There are also reports on reductases and polysaccharides as factors involved in biosynthesis and stabilization of the nanoparticles.
Nanoparticle synthesis depends on the plant source, the organic compounds in the crude leaf extract, the concentration of Ag nitrate, the temperature and even the pigments in the leaf extract. The plants Basella alba (Basellaceae), Helianthus annus, (Asteraceae), Oryza sativa, Saccharum officinarum, Aloe vera leaf extract, sunflower leaf extract, Sorghum bicolour and Zea mays (Poaceae) reduce Ag ions and form Ag nanoparticles.
By altering the pH, strength of elements, plant sources and incubation temperature of the nanoparticle synthesis reaction mixture, the synthesis methods, it is possible to create a wide range of different nanoparticles. Nanoparticles of various sizes and properties may be obtained by further tapping the plant bioresources of diverse type in wild environment.
1/25/11 1
A wonder textile that does not get wet. See www.nano4life.gr for more details.
http://www.youtube.com/watch?v=go03403oGpw
Nanomaterials have a wide range of potential applications, from medicine to consumer products and due to this there are plenty of chances for nanomaterials to get into humans, either deliberately as medicines or unintentionally as environmental contaminants. If nanoparticles are inhaled during manufacture, they get deposited in the lung near the alveolar duct bifurcation and white blood cells ingest these particles and carry along mucociliary escalator to be subsequently coughed out or swallowed. Such hazards are taken care off by selective proteins.Principle
A major protein involved in clearing nanoparticles is called scavenger receptor A. This protein found on the macrophages in blood takes up nanoparticles, for example more than half of silica nanoparticles up to 500 nm. These nanoparticles bind to clusters of positively charged arginine and lysine residues that form when the receptor folds. Using such information scientists design new particle surfaces that better target or evade the receptor in order to shorten or prolong the circulation time of nanoparticles in the human system.
Mechanism
When nanoparticles circulate in blood, they are surrounded by a “corona” of proteins which is about 10 nm thick for many nanomaterials, and this thickness does not change with time. The corona composition depends on the protein concentration in the biological fluid and hence the corona composition varies in different parts of the body. The protein corona surrounding a particular nanoparticle depends on a number of parameters, including particle composition, morphology, size, charge, the duration of exposure and plasma concentration. Whether the protein corona just helps make particles biocompatible or the composition of the corona in some way matters for the cellular machinery that processes the nanoparticles is still not clearly known. Most nanoparticles show strong affinity to proteins. Smaller particles seem to bind proteins more strongly, but no clear trend is reported about the dissociation kinetics of nanoparticles and proteins according to size and type.
Nanotechnology Companies in India
Auto Fibre Craft
AFC Powders is a company involved in manufacturing specialized nanomaterials. Currently it is manufacturing Nano-size Silver Powder for use in electronic applications for e.g. making conductive inks and pastes, RFID. This product is RoHS compliant.
Bee Chems
A chemicals company focused on the silica and alumina industries. Manufactures various grades of Nano Silica products.
Bilcare
Bilcare has developed a unique security technology called nonClonable. The technology innovatively exploits the intrinsic nature of nano and micro-structured composites together with their magnetic and optical properties to provide a foolproof security system.
Cranes Software
Cranes Software International Limited is a company that provides Enterprise Analytics and Engineering Simulation Software Products and Solutions. The company also focuses on niche research programs in some promising emerging technologies like MEMS and Nanotechnology.
Dabur Pharma
One of the company's delivery systems in the most advanced stages of clinical development is a novel drug delivery system for Paclitaxel. Because of the better safety and pharmacokinetic profile, the polymeric nanoparticle delivery system is seen as a potential super generic.
Eris Technologies
Eris Technologies is a software development company that also provided industrial training in areas like nanotechnology. Certification in nanotechnology covers course in applied nanotechnology where the dimensions and tolerances in the range of .1nm to 100nm play a critical role. The course covers nanotechnology basics, manufacturing process, lithography, CNT, nanocomputers ,nanomedicine and nanodiamond.
Icon Analytical Equipment
The company is a distributor of analytical instruments, with a focus on nanotechnology and related analytical techniques.
Micromaterials (India)
Micromaterials (P) Ltd. is a Bangalore based company focused on developing innovative nano and micro technologies and materials catalysts. The new generation catalysts are the result of a radically new patented process.
Mp3s Nanotechnology
The company's activity is the manufacture of equipment and chemicals based on nanotechnology. Its products include equipment for textile waste water recycling in dyeing and other process.
Nano Cutting Edge Technology NanoCET
Contract Research and New Product Development Work involving biostabilized nanoparticle technology.
NanoBio Chemicals
The mission of NanoBio Chemicals is to be the foremost producer of high quality nanoparticles using patented technology and also custom synthesis of complex peptides and biochemicals.
NanoFactor Materials Technologies
NanoFactor Materials Technology has a patent pending technology for synthesis of Carbon Nanotubes.
Nanoshel
Nanoshel makes more than 50 types of nanomaterials, among which the main products are nanotubes, SWCNT´s, MWCNT´s, nanoparticles.
Neo-Ecosystems
The company is specialized on researching and production of metal nanopowders.
Quantum Corporation
Quantum Corporation (QCorp) is the parent company of group of companies, head quartered in Bangalore, India. QCorp was established in 2007 with a vision to create world class Nanomaterials and Nanocomposites with strong Intellectual Property that are changing the properties of products across the globe. QCorp has developed high quality Smart Polymers, Nanomaterials and Nanocomposites as core materials for manufacturers in Telecommunications, Electronics, Drug Delivery, Conductive films, Lighting and Energy industries - without the need to change their existing processes.
Quantum Materials Corporation
The comapny manufactures carbon nanotubes and graphene.
Saint-Gobain Glass
The company manufactures SGG NANO, a high performance coated glass with advanced energy efficient solar control and thermal insulation (low e) properties. This Advanced Solar Control and Thermal Insulation (low e) Glass is manufactured by deposition of multiple layers of highly specialized nano-metric metallic oxides / nitrides by a process of magnetically enhanced nanotechnology-based cathodic sputtering under vacuum conditions.
U-Shu Nanotech
A consulting company providing services to the nanotechnolology community in India.
United Nanotechnologies
Manufactures nanoparticle-based coatings.
Velbionanotech
An R&D company in the nanobio and nanomedicine area.
Yashnanotech
Business information & consulting arm of Yash Management & Satellite Ltd. in Nanotechnology. It aims to provide global nanotechnology business intelligence and consulting services to industries and investors worldwide
Representative nanotech companies actively involved in business and research are listed below. Leading Nanotech Companies
• IBMResearch
IBM's nanotech research aims to devise new atomic-scale and molecular-scale structures and devices for enhancing information technologies, as well as discover and understand their scientific foundations. Domino.Research.IBM.com
• Nano Opto
This nanotech company creates new classes of densely integrated, modular nano-optic components.www.NanoOpto.com
• Nanocrystal Technology
Manufactures drug delivery solutions offering enhance absorption rates and bioavailability.www.Elan.com
• Pacific Nanotechnology
Provides products and services that facilitate advances in nanotechnology and nanoresearch.www.PacificNanotech.com
• Versilan
Pioneering the invention, development, and production of nanotechnology-based materials.www.Versilant.com
• Zyvex
Molecular nanotechnology company with applications in the areas of Materials, Tools, and Structures.www.Zyvex.com
• NanoDynamics
This leading nanotech company manufactures nanomaterials that may dramatically improve the form, function and performance of a wide range of consumer and industrial products.
Resources
Resources
• National Nanotechnology InitiativeMulti-agency framework to ensure U.S. leadership in nanotechnology.
• Nanotech Project
The Project on Emerging Nanotechnologies is dedicated to helping ensure that risks are minimized, public and consumer engagement remains strong, and potential benefits are realized as nanotechnologies continue to advance.www.NanotechProject.org
• Nanotechnology Investing - government and academic nanotechnology investing.
• nABACUS Nanotechnology Group
Nanotechnology consulting and investment house.
• Sevin Rosen FundsVenture capital firm with a successful track record of funding early-stage ventures.www.SRFunds.com
• Rensselaer Polytechnic InstituteAdvanced materials and nanotechnology research center.
• Sandia National Laboratories > Nanoscience and Nanotechnology"Thinking Big in a Nano Sized World."www.Sandia.gov\
• NanoBusiness AllianceIndustry association founded to advance the emerging business of nanotechnology and microsystems.
• Center for NanotechnologyConducts research work in nano and bio technologies.
• Phantoms FoundationInterdisciplinary nanobusiness and nanoelectronics research network.
• Fish & Richardson P.C. > Technology Areas > NanotechnologyProvides a full range of legal services to clients workings in nanotechnology
• Foresight InstituteLeading nanotechnology forum, focusing on the coming ability to build materials and products with atomic precision.www.Foresight.org
• Project on Emerging TechnologiesDedicated to helping ensure that as nanotechnologies advance, possible risks are minimized, public and consumer engagement remains strong, and the potential benefits of these new technologies are realized. The project was established in April 2005 as a partnership between the Woodrow Wilson International Center for Scholars and the Pew Charitable Trusts.
1/24/11
Scientists of the Technical University of Denmark have developed a new membrane filter to obtain ultra pure water with a main focus to get ultra pure water in the fabrication of semiconductors. All minerals, carbon compounds or gas molecules are filtered out by this special membrane. The filter could also be used to recycle sewage water.
Principle
The technology is based on a discovery of Prof Peter Agre who is a Nobel Prize winner and a molecular biologist from the Johns Hopkins University in Baltimore, USA. During his studies he discovered a special protein which is responsible for rapid permeation of water in cells. Peter Agre and his team named these proteins ‘aquaporins’, as they function as water pores on the nano scale. In plants they work like the plumbing system of cells and ensure a highly efficient but selective transport of water: only H2O molecules can pass through these channels. For plants this filter is a life-saver, as they make sure that the cell will not lose any minerals.
Ultra pure water
Ultra pure water
Ultra pure water is used in the semiconductor fabrication to clean silicon wafers residue-free. Even the smallest particles could affect the conductivity of the computer chips that will be fabricated from these silicon wafers. Big manufacturers therefore use millions of litres per day. Production of ultra pure water is complex, uses a lot of energy and is quite expensive.
Construction
Construction
Proteins are taken out of their natural environment and put into an artificial membrane mimicking the membrane of cells to construct a durable filter membrane, thereby creating a matrix in which these proteins sit in large quantities so that they can collectively work as a water filter.
The scientists have therefore constructed a net made from a perforated Teflon film that holds them together. The net holes are only 300 microns in diameter and are literally burned into the Teflon with a special kind of laser using CO2. The net is further supported with a second layer underneath the net made from porous hydrogel. It is flexible and resembles tissue, similar to soft contact lenses.
So far the researchers are testing their filters in lab experiments only and expect that it will soon become a practical device.
The scientists have therefore constructed a net made from a perforated Teflon film that holds them together. The net holes are only 300 microns in diameter and are literally burned into the Teflon with a special kind of laser using CO2. The net is further supported with a second layer underneath the net made from porous hydrogel. It is flexible and resembles tissue, similar to soft contact lenses.
So far the researchers are testing their filters in lab experiments only and expect that it will soon become a practical device.
1/24/11 2
Nano Fuel Saver uses both the latest nanotechnology and the principle of Far Infrared (FIR) to make driving experience extraordinary. After installation, it absorbs the heat energy from engine to lead out FIR thermal energy to minify fuel’s molecules, purify impurities contained in the fuel, advance atomization effect, enhance complete combustion, increase horsepower and torque, improve fuel economy, reduce engine vibration, faster acceleration, cut down fuel consumption, reduce engine carbon build-up, reduce toxic exhaust emissions to diminish air pollution, keep the engine in optimum condition to extend its lifetime, easy installation, no engine refit, and no chemical additive.
Nano Fuel Saver saves Fuel on ordinary cars starting from 5% - 15% depending various cars - trucks - lorry - if car or lorry is serviced every 5000 km good performance can be obtained. In layman’s terms the Nano Fuel Saver is a tube impregnated with nano-particles. When this tube gets heated up, it creates a wave called Far Infrared Ray (FIR). FIR is a part of the invisible light spectrum and it is in between visible light and microwave but not harmful to the human at all. In fact scientists call it the 'light of life'. Fuel Saver enters the gas tube into the engine and passes through the infrared ray which can increase the gas breakdown quality. This ray has a major effect on the petrol and diesel by resonating the fuel molecules in the fuel and preventing clustering of the hydrocarbons. Also this resonance makes the fuel molecules to be smaller. This is really like pumping high octane fuel into your car (i.e. super petrol/diesel). This allows the fuel and air to be mixed more evenly and efficiently before it is delivered into the engine for combustion. The overall result is more complete combustion without any residue, this can attain the goal of saving gas. More of the fuel is used for powering the car, and less is lost as harmful emissions as carbon monoxide. The gas will burned completely in the carburetor and the car horsepower will be increased. It also reduces air pollution, improves engine functions and prolonging the life span of engine. Most important its economic benefits by saving fuel. Fuel Saver is claimed to be Pb–Free products and does not contain the following six substances, as defined in the RoHS initiative: Lead, Cadmium, Mercury, Hexavalent Chromium, Polybrominated biphenyls (PBB) and Polybrominated diphenyl ethers (PBDE)
See for more details: http://fuelsaver.com.my/?gclid=CJaF9fSm06YCFUUa6wodom5_Gg
See for more details: http://fuelsaver.com.my/?gclid=CJaF9fSm06YCFUUa6wodom5_Gg
1/22/11
Nanotechnology research aims to devise new atomic- and molecular-scale structures and devices and to discover and understand their scientific foundations. This aim is spearheaded by a group of people who continue to creatively explore it. Here is a list of scientists and business leaders who have contributed actively in the field of nanotechnology.
• RICHARD FEYNMAN : Feynman worked as a professor at Cornell University, and then moved to Cal Tech in Pasadena, Calif., where he did much of his best work including research in quantum electrodynamics, the physics of the super fluidity of super cooled liquid helium, and a model of weak decay. He also developed Feynman diagrams, a book keeping device that helps in conceptualizing and calculating interactions between particles in space-time, notably the interactions between electrons and their antimatter counterparts, positrons.
• RICHARD FEYNMAN : Feynman worked as a professor at Cornell University, and then moved to Cal Tech in Pasadena, Calif., where he did much of his best work including research in quantum electrodynamics, the physics of the super fluidity of super cooled liquid helium, and a model of weak decay. He also developed Feynman diagrams, a book keeping device that helps in conceptualizing and calculating interactions between particles in space-time, notably the interactions between electrons and their antimatter counterparts, positrons.
• RICHARD SMALLEY: A professor at Rice University, Smalley is credited with discovering C60, the buckminsterfullerene. Also known as the buckyball, this is the key to the molecular structures which are most often used in nanotechnology. He founded the company Carbon Nanotechnologies Inc.
• CHARLES LIEBER: Charles Lieber is a Harvard University professor who developed the synthesis, characterization, and development of nano-scale wires. He founded the company Nanosys, Inc.
• HONGJIE DAI: Hongjie Dai of Stanford University studies the suitability of carbon nanotubes for future miniaturized devices. Because of the small size of carbon nanotubes this calls for extreme precision as he tries figure out their unique quantum effects.
• JAMES HEATH: James Heath helped run the experimental apparatus that helped Smalley discover C60 at Rice. He pioneered the molecular switch, using nanowires and molecules, and also developed a scanning optical microscope used to noninvasively probe the electrical functions of living cells.
• JAMES VON EHR II: He is the founder, chairman, and CEO of Zyvex Corporation, a company that specializes in nano-size manipulators. These tools allow scientists to work with nano-sized structures under a microscope.
• GEORGE WHITESIDES: A chemistry professor at Harvard and a member of the Nanotechnology Technical Advisory Board. George Whitesides' research influences material science, surface science, micro fluidics, self-assembly, and nanotechnology.
• PAUL ALIVISATOS: His major contribution to technology is his work with semi conducting nanocrystals. The crystals come in different shapes and sizes, such as quantum dots, nanorods, and tetra pods.
• ANGELA BELCHER: Belcher pioneered the use of genetically modified viruses in the self-assembly of nanowires, thin films, and other nanomaterials. Her work has a direct impact on drug discovery and delivery, materials and catalysts, and self-assembling electronic materials. • ERIC DREXLER : Eric Drexler developed ideas about molecular nanotechnology (MNT). The term nanotechnology was unknowingly appropriated by Drexler in his 1986 book Engines of Creation: The Coming Era of Nanotechnology to describe what later became known as molecular nanotechnology (MNT). In that book, he proposed the idea of a nanoscale "assembler" which would be able to build a copy of itself and of other items of arbitrary complexity. He also first published the term "grey goo" to describe what might happen if a hypothetical self-replicating molecular nanotechnology went out of control. His vision of nanotechnology spurred its growth.
• Naomi Halas : Naomi Halas of Rice University has invented tiny structures called "gold nanoshells," which may someday help treat tumors. Halas tunes the nanoparticles to absorb a specific wavelength of light that passes harmlessly through the human body. When that light hits the injected nanoshells, they grow hot enough to burn away targeted nearby tissue such as a tumor.
• Naomi Halas : Naomi Halas of Rice University has invented tiny structures called "gold nanoshells," which may someday help treat tumors. Halas tunes the nanoparticles to absorb a specific wavelength of light that passes harmlessly through the human body. When that light hits the injected nanoshells, they grow hot enough to burn away targeted nearby tissue such as a tumor.
• Jennifer West : Jennifer West is a researcher at Rice University. She has demonstrated the use of 120 nm diameter nanoshells coated with gold to kill cancer tumors and target to bond to cancerous cells by conjugating antibodies or peptides to the nanoshell surface. She is working with nanoshells that find and "cook" cancer cells.
• James Tour : He is a synthetic organic chemist, specializing in nanotechnology. He is well-known for his work in molecular electronics and molecular switching molecules. He has also been involved in other work, such as the creation of a nanocar and NanoKids. Tour's work spans an incredible breadth, from building tiny cars and trucks out of molecules, to making computer memory from graphite, building tiny missiles that carry drugs to tumors and trying to cure radiation sickness.
• Mark Reed : He used nanotechnology to come up with an inexpensive replacement for silicon-based computer chips and venture capitalists. Currently editor-in-chief. Reed is actively involved with key decisions in steering the journal as a leading publication in a research area of explosive development. He has contributed to nanotechnology in areas from quantum dots to molecular electronics. He has designed a new approach for creating nanodevices that allows them to integrate directly with microelectronic systems. This novel technology has broad application for low-cost, highly sensitive detection of molecules including biomolecules for medical diagnostics and therapeutics.
• Steve Jurvetson : He is a Managing Director of Draper Fisher Jurvetson, industrialist and a nanotechnology supporter. His technical experience includes programming, materials science research (TEM atomic imaging of GaAs).
• Josh Wolfe : He is co-founder and managing partner of Lux Capital, a venture firm focused on investing in nanotechnology. He is also the author of the groundbreaking “Nanotech Report. He is a senior Associate of the Foresight Institute for Nanotechnology and Co-Founder of the NanoBusiness Alliance. He has invested in nanotechnology.
• John Kanzius: He has invented a radio machine which uses a combination of radio waves and carbon or gold nanoparticles to destroy cancer cells.
1/22/11 0
1/21/11
International conferences on nanotechnology
22 - 27 January 2011: San Francisco, California, USA
SPIE Photonics West
25 - 27 January 2011: Ettlingen, Germany
3rd Annual Conference of the Innovation Alliance Carbon Nanotubes
3 February 2011: London, UK
MicroMaterials Nanomechanical Testing Technical Seminars
6 - 10 February 2011: Bhubaneswar, India
Ion-Beam Induced Nanopatterning of Materials (IINM-2011)
7 - 11 February 2011: Phoenix, Arizona, USA
Flexible Electronics and Displays Conference
7 - 11 February 2011: Wellington, New Zealand
Fifth International Conference on Advanced Materials and Nanotechnology (AMN-5)
8 February 2011: Swansea, UK
MicroMaterials Nanomechanical Testing Technical Seminars
17 February 2011: Lausanne, Switzerland
NanoImpactNet Training School: Reproducible Uptake & Quantification of Nanoparticles in vitro (and in vivo)
19 - 22 February 2011: Sharm el Sheikh, Egypt
Nanoscience Conference 2011
21 - 22 February 2011: Mexico
NanoBioMedica Congress and Expo
27 February - 2 March 2011: Cairo, Egypt
Nanotech Insight 2011
1 March 2011: Oxford, UK
MicroMaterials Nanomechanical Testing Technical Seminars
8 March 2011: Glasgow, UK
MicroMaterials Nanomechanical Testing Technical Seminars
8 - 10 March 2011: Dusseldorf, Germany
Commercialising Nanotubes 2011
30 March - 2 April 2011: Chicago, Illinois, USA
IEEE International Symposium on Biomedical Imaging: From Nano to Macro
5 - 6 April 2011: Oakbrook Terrace, Illinois, USA
NanoManufacturing Conference & Exhibits
5 - 7 April 2011: Nancy, France
INRS Occupational Health Research Conference 2011: Risks associated to Nanoparticles and Nanomaterials
11 - 14 April 2011: Bilbao, Spain
ImagineNano
11 - 14 April 2011: Bilbao, Spain
Graphene 2011
24 - 28 April 2011: New York, USA
US-EU-Africa-Asia-Pacific and Caribbean Nanotechnology Initiative (USEACANI) Workshop
24 - 29 April 2011: Obergurgl, Austria
Graphene Week 2011
2 May - 8 July 2011: Online Course
Online course: Fundamental characterisation for nanotechnology
11 - 13 May 2011: Poznan, Poland
International Conference on Quantum Metrology
15 - 18 May 2011: Assergi-L'Aquila, Italy
GraphITA - A Multidisciplinary and Intersectorial workshop on Synthesis, Characterization and Technological Exploitation of Graphene
23 - 27 May 2011: Grenoble, France
Frontiers of Characterization and Metrology for Nanoelectronics
29 May - 1 June 2011: Bordeaux, France
4th Workshop on Nanotube Optics and Nanospectroscopy (WONTON '11)
30 May - 1 June 2011: Budapest, Hungary
EuroNanoForum in Partnership with Nanotech Europe 2011
7 - 9 June 2011: London, UK
NanoMaterials 2011
7 - 9 June 2011: Bad Gastein, Austria
Intensive Course Nanomaterials
7 - 9 June 2011: Shanghai, China
Nanotech China 2011
13 - 16 June 2011: Boston, Massachussetts, USA
NSTI Nanotech 2011
20 - 26 June 2011: Grenoble, France
Graphene Fundamentals and Applications
26 June - 1 July 2011: Singapore, Singapore
NanoFormulation2011
24 - 30 July 2011: Shanghai, China
Nineteenth Annual International Conference on Composites/Nano Engineering (ICCE-19)
27 - 29 July 2011: Ottawa, Ontario, Canada
2nd International Conference on Nanotechnology: Fundamentals and Applications
9 - 12 August 2011: Boston, Massachussetts, USA
Fifth International Symposium on Nanotechnology - Ocupational and Environmental Health
15 - 18 August 2011: Portland, Oregon, USA
11th International Conference on Nanotechnology
21 - 25 August 2011: San Diego, California, USA
Metamaterials, Plasmonics, Carbon Nanotubes, Biosensing, Thin Films, and the 25th Anniversary of the Buckyball
11 - 14 September 2011: Namur, Belgium
International Symposium on Advanced Complex Inorganic Nanomaterials
13 - 14 September 2011: Radisson Blu Scandinavia Hotel, Dusseldorf, Germany
Nanopolymers 2011
14 - 15 September 2011: Torino, Italy
Nanoforum 2011
2 - 5 October 2011: Lake Louise, Alberta, Canada
WAVE 2011 - Taking Micro & Nano Products to Market
23 - 26 October 2011: Dalian, China
BIT's 1st Annual World Congress of Nano-S&T
11 - 15 December 2011: Waikoloa, Hawaii, USA
2nd Nano Today Conference
Source:http://www.nano.org.uk/nanotechnology-events
1/21/11 0
workshop on Nanotechnology for Water
Date: Tue 15 Feb 2011 - UCL, London
Background
Water treatment encompasses a range of engineering and technological processes and is of increasing importance worldwide due to increasing population, sources drying up and contaminants and increasing problems. Water is also a vital part of many industrial processes for producing chemicals and consumer products such as food and drink. Nanotechnology can enable a number of new approaches in water treatment, from nanosensors for quality control, tracers for effluent, purification technologies, catalysts, filters, and desalination etc.
Focus
NanoKTN's upcoming "Nanotechnology for Water" workshop will deal with ways in which nanotechnology could possible provide advanced solutions for water treatment and purification such as filtration and desalination.The agenda will be to address environmental challenges and the role of nanotechnology in remediation of water and air. The launch event will also aim at nanotechnology-awareness in the supply chain. The first part of the workshop is designed to raise the awareness about the possibilities offered by nanotechnology.
Participation
The workshop will attract a variety of industry sectors like water utilities, chemical processing, and pharmaceuticals, among others. The workshop will be attended by experts from the water industry, environmental industries and research communities and will have presentations from organizations such as Water UK, Anglian Water, Proaqua, IWA and some universities such as Aberdeen, Brighton and Bristol.
For details see: https://ktn.innovateuk.org/web/nanotechnology-for-water
1/20/11
An electrolyzer uses two different electrodes, one of which releases the oxygen atoms and the other the hydrogen atoms. Although it is the hydrogen that would provide a storable source of energy, it is the oxygen side that is more difficult, so that’s where many other research groups have concentrated their efforts. Nanowires are now used for efficiently splitting water into oxygen and hydrogen. Highly dense vertical arrays of nanowires made from silicon and titanium oxide and measuring 20 microns in height show promise for the efficient production of hydrogen through solar water splitting. Titanium dioxide electrodes are one way to split water under ultraviolet light but the efficiency is low as they are only able to absorb ultraviolet light and the conversion efficiency is low.Metal oxide nanowires
Researchers at Harvard University have synthesized TiO2 nanowires with high surface areas, deposited them on an electrode and found that chemically cross linking them increases their optical density allowing more light to be absorbed. This allows the light to energy conversion to be doubled compared to previous TiO2 electrodes. Doping the nanowire network with gold or silver nanoparticles allows the water splitting reaction to take place under visible light and could lead to a ten fold improvement in the catalysts ability to split water. The advantages of using titania, over other more systems is highly photostable, it is cheap and is also non-toxic. Water photo electrolysis with other metal oxides, such as iron oxide which can absorb visible light is also possible.
Researchers at University of California have fabricated devices using dense and vertically aligned metal oxide nanowire arrays, such as TiO2 and ZnO, as photo anodes. They have explored different methods including elemental doping and quantum dot sensitization to improve the visible light absorption of these wide band gap metal oxides. They prepared dense and vertically aligned ZnO nanowires from a hydrothermal method, followed by annealing in ammonia to incorporate N as a dopant. Upon illumination at a power density of 100 mW/cm2 (AM 1.5), water splitting was observed in both ZnO and ZnO:N nanowires.
New Catalyst
Researchers at MIT have found a formulation based on inexpensive and widely available materials that can efficiently catalyze the splitting of water molecules using electricity. Nickel borate made from materials function as the oxygen-producing electrode that are even more abundant and inexpensive than those used earlier such as expensive platinum catalyst.
1/20/11 0
Inorganic phosphors have luminescent properties and are used for commercial flat panel displays (FPDs). Mn2+ doped Zn2SiO4 and zinc sulfide phosphors are considered suitable materials for a FPD. Spherical Zn2SiO4 particles can be made using ZnSO4 as zinc source in an ammonia solution under a hydrothermal condition.Luminescence efficiency of zinc sulfide is satisfactory, but its stability under a cathode ray beam in high vacuum is questionable. This problem is overcome by a surface passivating agent layer (PAL), which is a new class of luminescence materials of doped nanocrystals combining high luminescence efficiency and decay time shortening. The doping of Mn2+ into ZnS lattice is achieved during the precipitation at room temperature in the solution or during the reaction of cations with H2S gas at an elevated temperature up to 200°C. Methacrylic acid (MA) is used as a surfactant in order to prevent nanoparticle agglomeration in the solution. PL enhancement up to ten-fold has been observed for polymethyl merthacrylate (PMMA) coated ZnS nanocrystals doped with Mn2+ ions.
Synthesis
Mn2+ doped ZnS nanocrystals are synthesized by a chemical precipitation method at room temperature using Zn(CH3COO)2 • 2H2O, Mn(CH3COO)2 • 4H2O and Na2S • 9H2O as starting materials.
A 50 mL ethanol solution is prepared by dissolving 2.195 g Zn(CH3COO)2 • 2H2O and 0.049 g Mn(CH3COO)2 • 4H2O with stirring at room temperature. This yields a Mn2+ doping concentration of 2 mole%. Then, a 50 mL aqueous solution of 2.451 g Na2S • 9H2O is added to the ethanol solution drop by drop with vigorous stirring. This results in white precipitate, which is centrifuged and washed using deionized water. Finally, 1.987 g of 3-methacryloxypropyl trimethoxysilane (MPTS) is added to the resultant mixture after centrifuging and washing.
Both photoluminescence and cathodoluminescence are observed from these Mn2+ doped Zn2SiO4 phosphor particles. A 30-fold enhancement has been observed after the surface passivation. This is achieved by eliminating the surface defects, in which the carboxylic groups with effective resonance/inductive effect in the surface modifying agent plays an important role.
A 50 mL ethanol solution is prepared by dissolving 2.195 g Zn(CH3COO)2 • 2H2O and 0.049 g Mn(CH3COO)2 • 4H2O with stirring at room temperature. This yields a Mn2+ doping concentration of 2 mole%. Then, a 50 mL aqueous solution of 2.451 g Na2S • 9H2O is added to the ethanol solution drop by drop with vigorous stirring. This results in white precipitate, which is centrifuged and washed using deionized water. Finally, 1.987 g of 3-methacryloxypropyl trimethoxysilane (MPTS) is added to the resultant mixture after centrifuging and washing.
Both photoluminescence and cathodoluminescence are observed from these Mn2+ doped Zn2SiO4 phosphor particles. A 30-fold enhancement has been observed after the surface passivation. This is achieved by eliminating the surface defects, in which the carboxylic groups with effective resonance/inductive effect in the surface modifying agent plays an important role.
The above work on green light emitting nanoparticle is from a report of researchers at Clemson University.
1/19/11
There are several nanotechnologies most likely to benefit the developing world in the near future. They are related to energy storage, production, and conversion; agricultural productivity enhancement, water treatment and remediation and diagnosis and treatment of diseases.
Brazil, India, China and South Africa have significant nanotechnology research initiatives that could address the needs of the developing world but breakthroughs in the health sector is presently benefiting a small section of people and hence responsible development of nanotechnology must include benefits for people in both rich and poor nations and at relatively low cost. This also requires that careful attention be paid to possible risks nanotechnology poses for human health and the environment. Few benifits are:
Carbon nanotubes could be used to repair brain material by keeping in contact with neuronal cell membranes to create shortcuts that generate neural excitation. This observation raises the hope of using nanotubes to repair certain lesions affecting the nervous system.
A process using recent findings conducted in the field of nanotechnology has been used to produce new metal surfaces. It provides medical implant-quality helping to facilitate healing and acceptance of metallic prostheses in the human body. The results of this study, the surfaces can stimulate cells directly, which eliminates the need to avoid certain drugs and, at the same time, side effects. This innovative approach could ultimately lead to the development of smart materials that not only would be accepted easily by the human body but, again, respond actively to the surrounding biological environment.
Nanomaterials possess various new properties and their industrial use creates new opportunities, but they also present new risks and uncertainties. Growing production and use of nanomaterials result in an increasing number of workers and consumers exposed to nanomaterials. This leads to a greater need for information on possible health and environmental effects of nanomaterials.
Carbon nanotubes could be used to repair brain material by keeping in contact with neuronal cell membranes to create shortcuts that generate neural excitation. This observation raises the hope of using nanotubes to repair certain lesions affecting the nervous system.
A process using recent findings conducted in the field of nanotechnology has been used to produce new metal surfaces. It provides medical implant-quality helping to facilitate healing and acceptance of metallic prostheses in the human body. The results of this study, the surfaces can stimulate cells directly, which eliminates the need to avoid certain drugs and, at the same time, side effects. This innovative approach could ultimately lead to the development of smart materials that not only would be accepted easily by the human body but, again, respond actively to the surrounding biological environment.
Nanomaterials possess various new properties and their industrial use creates new opportunities, but they also present new risks and uncertainties. Growing production and use of nanomaterials result in an increasing number of workers and consumers exposed to nanomaterials. This leads to a greater need for information on possible health and environmental effects of nanomaterials.
1/19/11 0
Gold nanoparticles have a high surface reactivity, biocompatible properties, used for in vivo molecular imaging, therapeutic applications, cancer detection, as in vivo sensors, photoactive agents for optical imaging, drug carriers and contrast enhancers in computer tomography and X-ray absorbers in cancer therapy. This is because high surface area and size relationships of nanoparticles to cells, which helps to target individual cells for diagnostic imaging or therapy. In spite of this, scientists have a challenge in that there are problems in making nontoxic gold nanoparticle constructs. Gold nanoparticles used to detect and treat cancer and other diseases can not remain in a stable, nontoxic form that can be injected into a patient. But a plant extract has been used to create a new type of gold nanoparticle that is stable and nontoxic and can be administered orally or injected. Georgia TechResearchers from the University of Missouri have developed a biocompatible and environmentally friendly method of obtaining gold nanoparticles. The research team was successful at identifying a natural phytochemical that would break down gold compounds into gold nanoparticles. The researchers have discovered how to produce and stabilize gold nanoparticles the "green" way with soybeans. The process involves bathing the gold salts in water and soybeans. The water draws a phytochemical out of the soybean that enables the breakdown of the gold into gold nanoparticles.Researchers have tested plant extracts for their ability as nontoxic vehicles to stabilize and deliver nanoparticles for in vivo nanomedicinal applications. One such plant extract is gum arabic, a substance taken from species of the acacia tree, which is already used to stabilize everyday foods such as yogurt. Gum arabic has unique structural features, including a highly branched polysaccharide structure consisting of a complex mixture of potassium, calcium and magnesium salts derived from arabic acid. The scientists found that gum arabic could be used to absorb and assimilate metals and create a "coating" that makes gold nanoparticles stable and nontoxic.
According to researchers the excellent in vivo stability profiles of such gold nanoconstructs will open up new pathways for the intratumoral delivery of gold nanoparticles in diagnostic imaging and therapeutic applications for cancer and can be administered either orally or through intravenous injection within the biological system. This discovery will initiate a new generation of biocompatible gold nanoparticles
1/18/11
Research work is going on in various institutes to employ nanotechnology to produce alternate fuel.
Ethanol from biomass
A research program at Purdue University focuses on applying nanotechnology and principles of polymer science to improve processing of cornstalks to ethanol which is an important biofuel. The researchers are using nanoscience to break apart cornstalks into nanomaterials for easier and cheaper transport of biomass for ethanol production.
A research program at the University of Marseille focuses on the fabrication of enzymatic nano-particles that make the breakdown of ligno-cellulose or any kind of cellulose-rich biomass into a potential biofuel feedstock more efficiently.
These projects give “medium” benefit to the environment, given their ability to replace fossil fuel. However, the life cycle issues (that is, energy, carbon dioxide emissions, and chemical use) associated with these processing steps need to be considered in full.
Biodiesel from waste fats
At Iowa State University, researches developed a nanotechnology that accurately controls the production of tiny, uniformly shaped silica particles that can transform (waste) fats and oils into biodiesel efficiently. The particles are basically honeycombs of relatively large channels that can be filled with a catalyst that reacts with soybean oil to create biodiesel. The particles can also be loaded with chemical gatekeepers that encourage the soybean oil to enter the channels where chemical reactions take place. The results include faster conversion to biodiesel, a catalyst that can be recycled and elimination of the wash step in the production process.
The nanoparticles can also be used as a catalyst to efficiently convert animal fats into biodiesel by creating a mixed oxide catalyst that has both acidic and basic catalytic sites. Acidic catalysts on the particle can convert the free fatty acids to biodiesel while basic catalysts can convert the oils into fuel. And the particles themselves are environmentally safe because they are made of calcium and sand.
Ethanol from biomass
A research program at Purdue University focuses on applying nanotechnology and principles of polymer science to improve processing of cornstalks to ethanol which is an important biofuel. The researchers are using nanoscience to break apart cornstalks into nanomaterials for easier and cheaper transport of biomass for ethanol production.
A research program at the University of Marseille focuses on the fabrication of enzymatic nano-particles that make the breakdown of ligno-cellulose or any kind of cellulose-rich biomass into a potential biofuel feedstock more efficiently.
These projects give “medium” benefit to the environment, given their ability to replace fossil fuel. However, the life cycle issues (that is, energy, carbon dioxide emissions, and chemical use) associated with these processing steps need to be considered in full.
Biodiesel from waste fats
At Iowa State University, researches developed a nanotechnology that accurately controls the production of tiny, uniformly shaped silica particles that can transform (waste) fats and oils into biodiesel efficiently. The particles are basically honeycombs of relatively large channels that can be filled with a catalyst that reacts with soybean oil to create biodiesel. The particles can also be loaded with chemical gatekeepers that encourage the soybean oil to enter the channels where chemical reactions take place. The results include faster conversion to biodiesel, a catalyst that can be recycled and elimination of the wash step in the production process.
The nanoparticles can also be used as a catalyst to efficiently convert animal fats into biodiesel by creating a mixed oxide catalyst that has both acidic and basic catalytic sites. Acidic catalysts on the particle can convert the free fatty acids to biodiesel while basic catalysts can convert the oils into fuel. And the particles themselves are environmentally safe because they are made of calcium and sand.
1/18/11 0
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation of a different wavelength. An initial ignition light energizes molecules, and then the molecules reemit the light with a different color in the case of ffluorescence. For the accurate detection of environmental pollutants, signals in biosensors and even in the detection of explosives fluorescent materials are used in many of these applications. This phenomenon is used in many different applications because it is easily detectable, using optical filters to remove the ignition light, leaving only the particles' light visible. Fluorescent nanoparticles offer enormous scientific and technological promise as labels and photon sources for a range of biotechnological and information-technology applications such as biological imaging, sensor technology, micro arrays, optical computing, and display technology.Fluorescent silica nanoparticles
A synthetic method has been developed to prepare fluorescent silica nanoparticles without employing isothiocyanated dye molecules and (3-aminopropyl) triethoxysilane (APS) for the thiourea linkage formation resulting in fluorescent silica nanoparticles with excellent photochemical, thermal and pH stabilities and a good biocompatibility with over 85% viability from various cell types.
Cornell’s Center for Materials Research (CCMR) and Nanobiotechnology Center (NBTC) have developed fluorescent, stable nano-particles with potential applications in many technologies, including photonics and bio-imaging. The Center has developed silica-based particles as an alternative to single molecule fluorophores and quantum dots through the Stöber process which holds particular promise since they are non-toxic, water soluble, the silica chemistry is well established and extremely versatile, and silica is compatible with semiconductor processing.
Brightest fluorescent nanoparticles
Researcher at Clarkson University has synthesizes brightest fluorescent nanoparticles applications in material science, medicine and biology. Particles of different colors can be created which can be made to stick to particular biological molecules inside cells. Then trace those molecules can be easily seen with existing fluorescent microscopes. This fluorescent labeling helps to identify diseased cells and may show the root cause of the disease. The particles are much more stable against photo-beaching than typical fluorescent dye enabling tracing of the particles for a very long time. The particles will have a significant impact in the biomedical area.
The process
The process involves physically entraps a large number of organic fluorescent molecules inside nanoporous silica particles, which can be 20 to 50 nanometers in diameter, while preventing the molecules from leaking. The fluorescence of 40-nanometer particles is 34 times brighter than the brightest water-dispersible (25-30 nanometer) quantum dots and seem to be the brightest nanoparticles created so far. It is claimed that many millions of these with almost identical diameters can be produced in a simple process, enabling many applications that will be inexpensive.
Researchers in US have produced electrically conducting yarns from bundle of carbon nanotubes and various powders and nanofibres. The yarns are made by a technique called biscrolling. The yarns are very strong and can be woven, sewn, knitted and braided into a variety of structures. They could find applications in energy storage and harvesting, structural composites, photo catalysis and intelligent textiles.Carbon nanotube yarns
Current methods to transform powders with useful properties into yarns involve using polymer binders to fix the powders in place. The problem is that the resulting composites are not very strong and the desirable properties of the powder usually degrade during processing. CNT sheets are ideal for making such yarns because they are very light, stronger than steel and can be easily washed.
Researchers at the Nanotech Institute at University of Texas in Dallas have developed a new method of making electrically conducting, sturdy yarns using carbon nanotube (CNT) sheets, or webs, instead of polymers to transform nano- or micron-sized powders.
Technique
The technique is similar to conventional textile-spinning methods. In the developed process, CNT sheets are overlayed with selected powders using an electrostatic powder-coating gun and then twist-spinning the stack to form a biscrolled yarn of 10 nm diameter made of multiwalled carbon nanotubes deposited on a substrate while applying a twist at the same time. Structures of different shapes can be produced and can be made from a variety of powders for various final applications. By this method superconducting yarn has been made by biscrolling a mixture of magnesium and boron powders (up to 99 wt %) as the guest on CNT sheets, and then thermally annealing the biscrolled yarn.
Applications
The biscrolled yarns can be made from a variety of powders that can be chosen according to the final application. The technique avoids the 30 or more drawing steps needed in conventional powder-in-tube methods to produce millimetre-sized, iron-clad, superconducting wires from a magnesium/boron/CNT precursor. The yarn has a high gravimetric electrical conductivity, highly flexible and mechanically robust and hence could be used in applications like energy storage devices such as for lighter batteries and energy-generating clothing textiles called intelligent textiles. These yarns could be used for making weavable anodes for flexible lithium-ion batteries, electrodes for lithium-ion batteries using environmentally friendly LiFePO4, highly catalytic fuel cell cathodes using nitrogen-doped carbon nanotubes which can avoid expensive platinum.
1/17/11
Nanotechnology has an impact on the food industry, from how food is grown and produced, processed to how it is packaged, transported and consumed. Companies are developing nanomaterials that will make a difference not only in the taste of food, but also in food safety, and the health benefits that food delivers. A report estimates that the worldwide nanotech food market may total more than $20 billion by 2020.Smart packages
Well-known applications of pure silver or silver-coated nanoparticles in food packaging materials are for plastic bags, containers, films or pallet. Researches have developed smart packages that can indicate the spoilage easily by consumers and manufacturers how much milk or meat is fresh. When the product gets oxidised in the package, nano-particles indicates the color change indicating if the product is fresh or not by the color chance of the package due to reaction of changed molecular composition of the milk with nano-particles. There smart packages also indicates if the food product is sterilized or contaminated and control gas exhaust from fruits and their freshness by sensing the change of the color due to CO2 exhaust from the products like cheese and easily indicates if the product is spoiled.
Antimicrobial property
Silver nanoparticles have become the promising antimicrobial material in a variety of applications because they can damage bacterial cells by destroying the enzymes that transport cell nutrient and weakening the cell membrane or cell wall and cytoplasm.
Testing food
Nanotechnology particularly molecular manufacturing technology has the potential for revolutionizing the methods used to test food products for contamination and spoilage using nano sensors. Using nanoparticles, the solubility of vitamins, antioxidants, omega fatty acids and other nutrients can be increased.
Plant uptake
Plants play a major role in food production and supply. But still the mechanisms of nanoparticle phytotoxicity which causes injury to plants is not clearly known and so much so is the fate of uptake of nanoparticles by plants into the food chain. Plants have thick and porous cell walls and a vascular system for water and nutrients uptake. The nanoparticle uptake and their accumulation may have impact on plant structure and their biological and biochemical processes. Research in this area is fairly scant, and among the few studies available, none have used major food crops or carbon nanoparticles. The interaction between nanoparticles and plants currently is poorly understood.
Toxicity
Nanotoxicology research mainly deals with the potential risk of nanomaterials which affect the human beings transmitted through various routes. Nanosilver used in food storage materials is found to interfere with DNA replication and acts as an antibiotic to human health. A study reports that nano silver particles can bind with double-stranded DNA and possibly result in compromised DNA replication fidelity both in vitro and in vivo.
1/17/11 0
Silver nanoparticles represent a prominent nanoproduct with potential application in medicine and hygiene. The inhibitory and bactericidal activities of silver ions have long been known. Some forms of silver have been demonstrated to be effective against burn infections, severe chronic osteomyelitis, urinary tract infections and central venous catheter infections. Based on these results, many silver-based antimicrobial materials have become available and several others are under development in research laboratories. Metallic nanoparticles can be obtained by physical, chemical or biological methods. However, biological synthesis is reliable and eco-friendly, and has received particular attention. In fact, a number of different species of bacteria and fungi are able to reduce metal ions producing metallic nanoparticles with antimicrobial properties. Recently, efficient antibacterial activity was observed against multi drug resistant and highly pathogenic bacteria, including multi drug resistant Staphylococcus aureus, Salmonella typhi, Staphylococcus epidermidis and Escherichia coli by silver nanoparticles produced by the fungus F. acuminatum. Additionally, plant extracts can also be used to obtain metallic nanoparticles.
Possible Mechanisms
Silver ions react with SH groups of proteins and play an essential role in bacterial inactivation. Micro molar levels of silver ions uncouple respiratory electron transport from oxidative phosphorylation, which inhibits respiratory chain enzymes or interferes with membrane permeability to protons and phosphate. These particles can penetrate and can disrupt the membranes of bacteria.
Silver nanoparticles fight pathogenic microorganisms. It has an anti-microbial activity and toxicity. In the presence of silver ions, bacterial cells reach an active but non-culturable state and eventually die. Probably there is an impairment of DNA replication and complete disruption of the bacterial membrane after few minutes in contact with silver nanoparticles. Depending on the particle size, silver nanoparticles accumulate in cell membranes while some penetrated into the cells. A massive loss of intracellular potassium is induced by silver nanoparticles and decrease the ATP levels resulting in the loss of cell viability.
However, resistant microorganisms are also present in environments where silver salts (e.g., silver nitrate, silver sulfadiazine) are used as antiseptics, such as in burn wards of hospitals. The antibacterial activities of several antibiotics is increased when used in combination with silver nanoparticles against the Gram-negative micro-organisms.
1/14/11
Barium titanate
Barium titanate (BaTiO3) is a classical ferroelectric material belonging to the group of perovskite materials. The molecular formula is BaTiO3, relative molecular weigh is about 233. 24. BaTiO3 has upper dielectric constant and piezoelectricity performance and is an important ferroelectric material. Barium titanate (BaTiO3) is the most studied, have received tremendous research attention in the past decades due to their unique ferroelectric, catalytic, sensing, superconducting, and optical properties for use in thin-film capacitors, pyroelectric detectors, electro optic modulators, transducers, actuators, optical memories, and nonlinear optics.
Uses of barium titanate
Uses of barium titanate
Barium Titanate(BaTiO3) of high purity and low particle size of 0.1-0.5um, is widely applied to the field of specific electronic ceramics such as MLCC, PTC, microwave dielectric ceramic etc. Nanoceramics
Nanoceramic functional particles are difficult to handle and process because of the high surface area to volume ratio of these particles.
Uses of nanoceramics
Nanosize dielectric ceramic particles are used in the development of volume-efficient multilayer ceramic capacitors (MLCCs). Barium titanate (BaTiO3 : BT) is one of the most important dielectric material widely used for MLCCs and future nano-electronics. Ceramic-based nano composites have the potential to yield materials with enhanced permittivity, breakdown strength (BDS), and reduced strain, which can increase the energy density of capacitors and increase their shot life.
Barium titanate nanomaterials
Barium titanate nanoparticles, nanopowder, nanodots or nanocrystals are spherical or faceted high surface area nanocrystalline alloy particles with magnetic properties. Nanoscale barium titanate particles are typically 20-40 nanometers (nm) with specific surface area (SSA) in the 30 – 50 m 2 /g range and also available in with an average particle size of 100 nm range with a specific surface area of approximately 7 m 2 /g. Nano barium titanate particles are also available in ultra high purity and as coated and dispersed forms.
Synthesis of BT
Various approaches have been explored for the synthesis of BaTiO3 nanocrystals, such as injection-hydrolysis, thermal decomposition, and peptide assisted precipitation, none to date have enable shape control. To overcome this limitation, ISU researchers have developed a one-pot non-hydrolytic approach for shape controlled synthesis of ferroelectric BaTiO3 nanocrystals. By tuning the molar ratio between the surfactant and metal precursors, BaTiO3 nanocrystals with different shapes, such as nanoparticles, nanorods, and nanowires, can be obtained.
In an industrial scale, BT powders are synthesized by a solid state reaction at high temperatures using hydrothermal method which has a special advantage over conventional solid state reaction due to the quasi-atomic dispersion of Ba2+ and Ti4+ in a liquid precursor, leading to a nucleation and crystallization process occurring at low temperatures under a high pressure, yielding high purity particles.
BT nanocrystals are synthesized by controlling the nucleation and growth by modifying the surface inhibiting further growth. The growth inhibitor adsorbate may also be utilized as a built-in dispersant for processing of the powder. For the Synthesis of BaTiO3 nanocrystals, nanowires and nanotubes synthesis methods include hydrothermal/solvothermal synthesis, co precipitation and sol-gel processing, pyrolysis and decomposition of bimetallic alkoxide precursors in the presence of coordinating ligands, liquid-solid-solution phase transfer, peptide templates assisted room temperature synthesis, low temperature aqueous synthesis with seed-mediated growth method and sol-precipitation route.
Using BaCl2 and TiCl4
When nano BT is synthesized by using an aqueous solution of BaCl2 , it is mixed with an aqueous solution of TiCl4. Polyoxyethylene sorbitan monooleate is added as a polymeric stabilizer into above solution at a concentration of 5.0 wt%. A high pH is maintained by KOH. The resulting milky sol is filled in a high-pressure stainless steel vessel and heated to 100oC ~ 230oC for 10 min to 2 h. The resultant nanocrystals are washed with deionized water and dried to get nano BT.
Bimetallic BaTi molecular precursor: Barium titanium glycolate (BTG)
In another procedure for BaTiO3 nanocrystal synthesis, a single bimetallic molecular precursor was used to ensure a correct stoichiometry of the product. The BaTi precursor barium titanium glycolate BaTi C2H4O2 34C2H6O2H2O was first prepared in a dry box by mixing BaO, ethylene glycol, 2-propanol, and Ti OPr 4. The resulting white powder was filtered, washed, dried at 60 °C, and kept in dry box because of its hygroscopic property.
Hydrothermal technique
Nanocrystalline barium titanate was synthesized by the hydrothermal technique at low temperature and atmospheric pressure, an optimum synthesizing temperature in the hydrothermal technique is found at 80 °C, at which the as-prepared nanocrystal barium titanate shows an excellent lattice structure and the strongest PL at room temperature.
Barium titanate was synthesized using a wet chemical technique followed by a high temperature and high-pressure hot isostatic pressing treatment and can be a processing step toward the ability to prepare textured films based on assembly of nanoparticles. Essential to this approach is an understanding of the nanoparticle as a building block, combined with an ability to integrate them into thin films that have uniform and characteristic electrical properties. This method offers a versatile means of preparing BaTiO3 nanocrystals, which can be used as a basis for micro patterned or continuous BaTiO3 nanocrystal thin films. We observe the BaTiO3 nanocrystals crystallize with evidence of tetragonality. We investigated the preparation of well-isolated BaTiO3 nanocrystals smaller than 10 nm with control over aggregation and crystal densities on various substrates such as Si, Si/SiO2,Si3N4 / Si, and Pt-coated Si substrates. BaTiO3 nanocrystal thin films were then prepared, resulting in films with a uniform nanocrystalline grain texture.
Sol-gel method
The sol-gel method for obtaining nanocrystalline particles of BaTiO3 is relatively simple and easy to carry out. This method has a few important advantages in comparison to the conventional solid state method (SSM). The sol-gel route is less expensive (temperatures lower than 1000 deg.C), enables a high concentration of dopant to be introduced, and assures a better control of reaction conditions such as pH or temperature. The sol-gel type synthesis from a bimetallic alkoxide precursor in conjunction with a solvothermal technique produces crystalline particles with controllable size. The other method involves the organic-metallic reaction of the bimetallic alkoxide precursor with hydrogen peroxide at high temperature. This procedure forms monodisperse BaTiO3 particles that are soluble in non-polar solvents.
Solvothermal reaction of a mixture of metallic barium and titanium isopropoxide in acetophenone leads to the formation of barium titanate nanocrystals.
BaTiO3 nanocrystallites
For the preparation of BaTiO3 nanocrystallites barium acetate, titanium butoxide and neodymium oxide were used as starting materials. Acetylacetone and acetic acid were selected as solvents for titanium butoxide and barium acetate, respectively. Neodymium chloride was obtained by reacting stoichiometric amounts of neodymium oxide with hydrochloric acid. Dissolved barium acetate was added drop wise to titanium butoxide solution while stirring. The obtained solutions were vigorously stirred at 50 deg.C for about 2 h. The neodymium salt was dissolved in a small amount of water and added slowly to the obtained transparent yellow sol with specific molar ratios of Nd3+ to BaTiO3. The sol obtained was heated at approximately 100 deg. C for 24 h to form barium titanate gel. The crushed gel was heated above 700 deg.C to form nanocrystalline BaTiO3 powders doped with Nd3+. The average size ranged between 30 and 60 nm, depending on the dopant concentration and sintering temperature.
In another procedure thin laminates (thickness 20-45 nm) of barium titanate, BaTiO3 (BT), have been synthesized by the sol-gel method followed by heating of the amorphous precursor powder in air. An orthorhombic BT polymorph forms along with a tetragonal phase (t-BT) after 2 h of heating the precursor at 600°C, as evidenced by a well-defined X-ray diffraction pattern.
In another procedure thin laminates (thickness 20-45 nm) of barium titanate, BaTiO3 (BT), have been synthesized by the sol-gel method followed by heating of the amorphous precursor powder in air. An orthorhombic BT polymorph forms along with a tetragonal phase (t-BT) after 2 h of heating the precursor at 600°C, as evidenced by a well-defined X-ray diffraction pattern.
Uses of nanocrystals
These nanocrystals may have utility as nanoscale modules for the assembly of various electronic devices, such as sensors, detectors, capacitors, etc; in addition, BaTiO3 nanocrystals can also be used in multifunctional structural capacitors (where material elements simultaneously carry load and store energy) and related transducers and sensors.Barium titanate (BaTiO3) is a material that has potential as a data storage medium that can be read optically and written electrically, since it is both ferroelectric and birefringent.
There are several advantages of using these materials for data storage since they maintain their polarization state after the applied voltage has been removed, they do not require back up memories or batteries. They can be accessed more quickly and with less power than many memory devices, which need to push electrons through a glass barrier. Additionally, they have potential for increased miniaturization.
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