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BIONANOMACHINES

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Transcription, like replication, displaces nucleosomes from DNA, and reassembly appears to occur in the wake of the RNA polymerase. Most transcribed genes thus retain a nucleosome structure, although the pattern of nucleosome phasing characteristic of non transcribed genes is lost, resulting in a smear of DNA fragments following digestion with micrococcal nuclease and a restriction enzyme, rather than a discrete band.

 Experiments which examine the progress of the polymerase complex through the nucleosome have shown that pausing occurs about half-way through the core DNA, which may reflect the build-up of torsional strain enzyme attempts to negotiate the first coil released from the nucleosome. The strain is release the enzyme moves past this point, indicating that the octamer is expelled. The octamer then reassociates with DNA behind the enzyme, perhaps because it remains attached to the nontran scribed strand, or perhaps because it is transiently associated with the enzyme itself.

In heavily transcribed genes sucha s the rRNA genes of Zampbrush chromosomes (q.v.), the extended conformation of chromatin indicates that it is nucleosome-free. This probably reflects failure ofthe displaced histones to reassemble on post transcribed DNA because of a following transcriptionalelongation complex. In very active genes, there would be a convoy of RNA polymerases which would maintain an definite nucleosome-free region of chromatin.manipulating nanomachines, now available commercially. In general, natural bionanomachines are remarkably robust.

THE UNFAMILIAR WORLD OF BIONANOMACHINES:

Biological machinery is different from anything we build with our familiar,human-sized technology. Natural biomolecules have organic, visceral, and often unbelievable shapes, unlike the tidy designs of toasters and tractors.They perform their jobs in a foreign environment, where jittery thermal motion is constantly pushing and pulling on their component parts. They are held together by a complex collection of bonding and non bonding forces. At their small scale, bionanomachines are almost immune to the laws of gravity and inertia that dominate our machines. The world of bionanotechnology is an unfamiliar, shifting world that plays by different rules.

From Microscopy To Nanoscopy

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Until fairly recently, the resolution of light microscopes was limited by the wavelength of the light. This means that details finer than 200 nanometers (millionths of millimeters) cannot be observed. There are non-optical methods, such as electron microscopy, but light microscopy is still the only way to observe the interior of whole, or even living, cells.

The use of fluorescent dyes makes it possible to selectively obtain images of individual cell components, for example, proteins. Today, the wavelength dogma is overcome. Hell received the German Future Prize in 2006 for the first concept breaking the wavelength barrier the stimulated emission depletion (STED) microscope . Molecules are transferred from a “dark” (non-fluorescent) to a “bright” (fluorescent) excited energy state—with a spacial sharpness far beyond those 200 nanometers.

Now the german team is demonstrating the power of another concept. They use molecules that are not only transferred but can be “switched” from “fluorescent” to “non-fluorescent” and back. In contrast to the STED and other related methods of the team, only separate, isolated marker molecules are randomly switched on at the same time. Their fluorescence is registered, and then they get switched off again automatically. In this way, the simultaneously fluorescing (switched on) markers are farther apart from each other than the minimum distance that the microscope can resolve.

This is only possible using switchable molecules that emit many photons, one after the other, when switched on. If these photons are captured with a camera, the centers of the individual fluorescing dots can be distinguished. After the exposure, the molecule becomes dark again (switches off), allowing further, neighboring molecules to be photographed. This process is repeated many times, until many dots become a picture. The full distribution can be reconstructed—at a resolution not limited by the wavelength of light.
The researchers have now found a class of substances that fulfill all the requirements of this technique: rhodamine amides. At the core of these molecules lies a system of five rings. In this form, the compound is colorless and does not fluoresce. Irradiation with light induces an isomerization in which one of the rings is opened. This form of the molecule is red and can be excited several times.

Most importantly: rhodamine amides can be switched on by either a UV photon or two photons in the red part of the spectrum. This two-photon excitation can be focused onto a thin plane, which allows biological samples to be photographed layer by layer. The individual images can then be reconstructed into a single multilayer image. The resolution reached in the focal plane is far beyond the diffraction barrier (10–30 nm).

A Call for Nanopollution Awareness

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As technology enters the close of the first decade this millennium, nanotechnology becomes increasingly more important in product development. Processors, chipsets, memory, displays and other electronics are marching toward the use of nanotech at and astonishing rate. In the U.S., we're already developing technology manufactured at the nanometer and sub-nanometer (picometer) level.

Carbon nanotubes, a high strength and versatile material composed of molecular configurations of pure carbon, may be the key to next generation technology in everything from the space elevator to high-speed processors. But outside of research, nanotech is here already. Research advocates have identified more than 400 consumer products in the U.S. labeled as "nano-based."  Some of these products, like microprocessors, pose relatively little risk to consumer, but the long term effects of other products like nano-aerosols is a bit less understood.  Additionally, the manufacturing by-products of these products are completely unregulated or monitored.

Nanotech and the production of nano-based devices create a type of pollution that is so small, it is extremely difficult to detect or contain. Researchers are afraid of the effect that nanopollution might have on humans, animals and other living organisms.

Nanoparticles are so small that they easily penetrate cells, a handy technique when geneticists attempt to modify genes when done intentionally. However, even when deliberate, the body detects foreign objects and creates phagocytes to break down invading material. Of course, if the body's phagocytes are busy digesting nanoparticles, the cells can't break down bacteria or other debris inside the body. Quantum dots, or nanoparticles used for semiconductors, are so small that they will actually pass right through cell walls -- yet we have relatively little research on what occurs when quantum dots interact with the human body.

Nano-CMOS Design for Manufacturability

Discover innovative tools that pave the way from circuit and physical design to fabrication processing Nano–CMOS Design for Manufacturability examines the challenges that design engineers face in the nano–scaled era, such as exacerbated effects and the proven design for manufacturability (DFM) methodology in the midst of increasing variability and design process interactions. In addition to discussing the difficulties brought on by the continued dimensional scaling in conformance with Moore's law, the authors also tackle complex issues in the design process to overcome the difficulties, including the use of a functional first silicon to support a predictable product ramp. Moreover, they introduce several emerging concepts, including stress proximity effects, contour–based extraction, and design process interactions. 

The sequel to Nano–CMOS Circuit and Physical Design, taking design to technology nodes beyond 65nm geometries. It is divided into three parts: Part One, Newly Exacerbated Effects, introduces the newly exacerbated effects that require designers' attention, beginning with a discussion of the lithography aspects of DFM, followed by the impact of layout on transistor performance Part Two, Design Solutions, examines how to mitigate the impact of process effects, discussing the methodology needed to make sub–wavelength patterning technology work in manufacturing, as well as design solutions to deal with signal, power integrity, WELL, stress proximity effects, and process variability Part Three, The Road to DFM, describes new tools needed to support DFM efforts, including an auto–correction tool capable of fixing the layout of cells with multiple optimization goals, followed by a look ahead into the future of DFM Throughout the book, real–world examples simplify complex concepts, helping readers see how they can successfully handle projects on Nano–CMOS nodes. It provides a bridge that allows engineers to go from physical and circuit design to fabrication processing and, in short, make designs that are not only functional, but that also meet power and performance goals within the design schedule.

Nano-emulsions and Micro-emulsions

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Much research has been done over the past years on self-emulsifying drug delivery systems, their main interest being the simplicity of the formulation processes, the great stability of the systems and their high potential in pharmaceutical applications and industrial scaling-up. Self-emulsifying drug delivery systems are generally described in the literature indiscriminately as either nano-emulsions or micro-emulsions. Although this misconception appears to be common, these two systems are fundamentally different, based on very different physical and physicochemical concepts. 

Their differences result in very different stability behaviors, which can have significant consequences regarding their applications and administration as nanomedicines. This paper aims at clarifying the problem, first by reviewing all the physical and physicochemical fundamentals regarding these two systems, using a quantitative thermodynamic approach for micro-emulsions. Following these clarifications, we show how the confusion between nano-emulsions and micro-emulsions appears in the literature and how most of the micro-emulsion systems referred to are actually nano-emulsion systems. 

Finally, we illustrate how to clear up this misconception using simple experiments. Since this confusion is well established in the literature, such clarifications seem necessary in order to improve the understanding of research in this important field.

Nanochemistry

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Nanochemistry is a branch of nanoscience dealing with synthesis, characterisation and applications of nanomaterials. Various chemical and physical techniques are used to manipulate atoms and molecules ranging in size between 1-100nm. These are used as building blocks to form nanomaterials, nanostructures, nanobots and nanoassemblies. When these are coupled with biological materials such as neurons or electronics or computers exciting new  possibilities and  applications emerge. 

Chemical reactions can be used to assemble atoms in molecular structures and physical techniques are employed to manipulate and position atoms for specific applications. Novel chemical synthesis can be used to make nanoscale structures used for building blocks with the desired shapes, surface area, structure, composition and size. The nanoscale feature endows unique structural and optical properties for use in catalysis, electro-optical devices and nanocarrier systems for drug delivery.There are many naturally occuring nanoassemblies such as liposomes, polypeptide miscelles etc.Nanomaterials exhibit properties that are distinct  to those of bulk materials and have important applications such as sunscreens to block harmful UV light from the sun and catalysts with an unusually large surface area to speed up chemical reactions in industrial production of important compounds and medical products.

One of the most popular nanomaterial is the carbon nanotube.  These have 1/6th  the weight of steel but much stronger.  Other materials may also form nanotubes. They can be excellent insulators or conduct electricity better than copper used in semiconductor devices. TiO2 is commonly used in self cleaning windows and ovens.

Spectroscopy and Microscopy Of Nanomaterials

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Nanomaterials have attracted significant attention in recent years for various fascinating applications, including ultrasensitive chemical/biological sensors, recording media, electronic circuits, nano-medical treatments, and so forth. Spectroscopy at high spatial and time resolutions is needed to attain direct access to the fundamental nature of nanomaterials. The spatial resolution of conventional optical microscopes is diffraction-limited to approximately several hundreds of nm. Near-field optical methods overcome the diffraction limit of light and achieve nanometric spatial resolution. The advantages of the near-field method go beyond high spatial resolution and include potential compatibility with various advanced spectroscopic techniques, such as time-resolved and nonlinear methods developed in the field of laser spectroscopy. The near-field methods enable us to obtain spectroscopic information of nanomaterials in a real space.

The research interests currently focus on the properties of surface plasmon resonances excited in noble metal nanostructures and their significance for chemical reactions. Plasmons confine optical fields in the vicinity of nanomaterials and enhance optical fields locally. This enhancement is of several orders of magnitude, opening up not just new research fields, but various potential applications. For basic research, since the spatial scale of the optical field becomes comparable to that of the materials, we expect strong, anomalous light-matter interactions beyond the dipole approximation. On the other hand, in applications, for instance, the optical field can be utilized for sensing purposes, since the enhanced field significantly amplifies Raman scattering from molecules to achieve detection sensitivity capable of detecting even single molecules. Imaging the plasmon wave function is essential for designing and controlling the properties of plasmon-based materials and for finding applications to basic research.

Nano Characterisation Techniques

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State-of-the-art analysis and measurement technology for the physico-chemical characterisation of nanomaterials is available at BAM. Testing procedures for specific tasks are developed and validated in are labs. Many testing procedures are ISO-certified. Most of our characterisation and testing work is carried out in accredited laboratories.

More and detailed technical information on our measuring techniques, resolution, accuracy, practical requirements and application areas beyond nanotechnology.The following measurement technology is available:
  • X-ray analysis
  • Electron microscopy
  • Scanning probe microscopy
  • Auger-electron microscopy
  • Optical techniques
  • Mass spectrometry
  • Dielectric spectrometry
  • Characterisation of powders and dispersions
  • Indentation testing
  • Particle counting
  • Elemental trace analysis  
X-ray analysis
Measuring techniques:
  • XANES/NEXAFS (X-ray Absorption Near Edge Structure/Near Edge X-ray Absorption Fine Structure)
  • SAXS (Small Angle X-ray Scattering)
  • XRD (X-ray Diffraction)
  • XRF (X-ray Fluorescence Spectroscopy)
  • XPS/ESCA (X-ray Photoelectron Spectroscopy/Electron Spectroscopy for Chemical Analysis)
  • EDX (Energy Dispersive X-ray Spectroscopy)
  • WDX (Wavelength Dispersive X-ray Spectroscopy)
  • µXRF (Micro X-ray Fluorescence)
  • TXRF (Total Reflection XRF)
  • GIXRF (Grazing Incidence XRF)

Spectroscopic Techniques for Studying Optical Properties of Nanomaterials

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Optical Spectroscopic techniques are widely used in the study of optical properties of different materials including nano materials. The different techniques are usually based on measuring absorption, scattering or emission of light that contains information about properties of materials. commonly used techniques include electronic absorption(UV-Vis), photo luminescence(PL), infra red (IR),absorption, Raman Scattering, dynamic light scattering, as well as time solved techniques.Such as transient absorption and time resolved luminescence.

Other more specialized techniques include single molecular spectroscopy and non linear optical techniques such as 2nd harmonic or sum frequency generation and luminescence up-conversation. These different technique can provide different information about molecular properties of interest.The main objective is to explain how one can get useful physical information about nano materials under the study from the optical spectrum, measured experimentally.

INTELLECTUAL PROPERTY RIGHTS OF NANOTECHNOLOGY

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With the emergence of any new technology, nanotechnology creates opportunities as well as challenges in adapting the patent regime to its particular context. There is some consensus that patenting nanotechnology innovations poses more problems than other technologies, owing to their multi-disciplinary character, cross-sectoral applications, broad claims as well as difficulties in fulfilling the patentability criteria.

 This is aggravated by the lack of a standardized terminology which impedes easy identification of nano-patents and also the fact that patent offices may not be well-equipped to handle nanotechnology. These problems are likely to be compounded for developing and least developed countries, which irrespective of their state of technological advancement, and capacity of the domestic regime, are obliged to confer IPR in the new technology.

In order to keep a desired level of in depth analysis this work will only contemplate the TRIPS Agreement. The paper finally arrives at certain recommendations, to help reconcile the need to incentivize innovation in the new technology, with the imperative of ensuring that the public interest is served and access to the patented knowledge is not hindered.

Nanotechnology, From Science To Commercialization

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In the past two decades the nanotech community has progressed from theory to the commercialisation of nanotechnology. Advances in the nanotechnology have the potential to reshape every aspect of industry and commerce offering business and consumers more efficient solutions to life's challenges and significant profit potential to investors who recognize the possibilities.

Today there is a widely accepted definition of nanotechnology; the design, production, and application of structures, devices, and systems by controlled manipulation of size and shape at the nanometer scale (atomic, molecular, and macromolecular) that produces at least one new or superior characteristic or benefit.

But moving from the science to commercialisation of nanotechnology is about more than just throwing money at research and hoping some of it will get lucky and find a rare entrepreneur who understands both the complexities of the technology and how to market it. Investors need to have an understanding about which sectors are likely to benefit from the science; like clean energy and healthcare and when those profits are likely to materialize. Some ideas come too early for widespread acceptance or offer profits in the too-distant future. Portfolio managers need to match the development and commercialization of the product with the investment horizon of the investor.



Thinking Of Launching Your Own Nanotechnology Business

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The first thing to understand about nanotechnology is that much of the groundwork it being done in university labs. Most nanotech businesses end up spinning off from these labs. Gittins refers to nanotechnology as "the dawn of the next industrial revolution." It will be increasingly important for entrepreneurs to know about and leverage nanotech discoveries. To that end, keep an eye on what the research labs are doing.

Find the business connection. Universities may be where the research happens, but they don't usually specialize in commercialization. There's a need for smart businesspeople to help make that leap. "Nanotechnology is driving a change in the way universities deal with businesses," says Gittins. You don't necessarily have to be a nanotech researcher to bring nanotech advances to the consumer and business markets.Leverage new discoveries. Nanotech is moving right along, and new discoveries are popping up on a regular basis. Keep an eye on the nanotech scene to see if any of the new breakthroughs are right for your business or products.Uncover the compelling reasons. Technology for technology's sake usually isn't a good idea. And that includes nanotech. Just because you can apply a nanotech coating to your existing product, doesn't necessarily mean you should. Look for the compelling reasons for why it truly makes your product better or sets you apart from the competition
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Physical Properties Of Nanoemulsions

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Nanoemulsions have many interesting physical properties that are different from or are more extreme than those of larger microscale emulsions. In this section, we focus on a few of the physical properties that distinguish nanoemulsions from microscale emulsions as an important new class of soft materials. We examine the relative transparency of nanoemulsions, their response to mechanical shear or ‘rheology’ and the enhanced shelf stability of nanoemulsions against gravitationally driven creaming. We do not intend to provide a comprehensive review of all of the possible properties, but these particular properties serve as a few primary examples.Nanoemulsions appear visibly different from microscale emulsions since the droplets can be much smaller than optical wavelengths of the visible spectrum.

By contrast, nanoemulsions can appear nearly transparent in the visible spectrum and exhibit very little scattering despite significant refractive index contrast. Quantitative measurements of the optical transparency of nanoemulsions in the visible and ultraviolet wavelengths are shown through transmission measurements .Nanoemulsions having a = 40 nm at several different f have been loaded into 0.2 mm pathlength quartz cells, and the per cent transmission intensity has been measured as a function of light wavelength. For all f, the transmission in the visible spectrum is near 100%, especially toward red wavelengths, indicating a high degree of transparency. By contrast, in the ultraviolet (UV) part of the spectrum, as the wavelength of light begins to approach the droplet radius, the nanoemulsions scatter light significantly. 

As it increases from the dilute regime up to about f ˜ 0.13, the transmission in the ultraviolet drops as the number of scatterers increases, yet at higher f > 0.13, the UV transmission increases again, indicating that more concentrated emulsions scatter less light. This increase and subsequent decrease in the scattering of light by the droplets as f is increased arises from the behaviour of the nanoemulsion’s structure factor in the low q (transmission) limit. In effect, correlations in the droplet positional structure cause the increased transparency at higher f. The smaller the droplet radius, the broader the range of visible wavelengths over which the transparency is found, especially toward the blue and the ultraviolet wavelengths.

NANOEMULSIONS

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Nanoemulsions can be defined as oil-in-water (o/w) emulsions with mean droplet diameters ranging from 50 to 1000 nm. Usually, the average droplet size is between 100 and 500 nm. The terms sub-micron emulsion (SME) and mini-emulsion are used as synonyms. Emulsions which match this definition have been used in parenteral nutrition for a long time. Usually, SMEs contain 10 to 20 per cent oil stabilized with 0.5 to 2 per cent egg or soybean lecithin.

Preparing Nanoemulsions Using the High-Pressure Homogenization Method:
The preparation of nanoemulsions requires high-pressure homogenization. The particles which are formed exhibit a liquid, lipophilic core separated from the surrounding aqueous phase by a monomolecular layer of phospholipids. The structure of such lecithin stabilized oil droplets can be compared to chylomicrons. Nanoemulsions therefore differ clearly from the liposomes, where a phospholipid bilayer separates an aqueous core from a hydrophilic external phase . If nanoemulsions are prepared with an excess of phospholipids, liposomes may occur concurrently.

Benefits of Using Nanoemulsions in Skincare Products:
Due to their lipohilic interior, nanoemulsions are more suitable for the transport of lipophilic compounds than liposomes. Similar to liposomes, they support the skin penetration of active ingredients and thus increase their concentration in the skin. Furthermore, nanoemulsions gain increasing interest due to their own bioactive effects. Nanoemulsions are able to favor the transport of suitable lipids into the skin. This may reduce the transepidermal water loss (TEWL), indicating that the barrier function of the skin is strengthened.

Nanoscale Thermocapillary - Single-Walled Carbon Nanotubes

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Among the remarkable variety of semiconducting nanomaterials that have been discovered over the past two decades, single-walled carbon nanotubes remain uniquely well suited for applications in high-performance electronics, sensors and other technologies. The most advanced opportunities demand the ability to form perfectly aligned, horizontal arrays of purely semiconducting, chemically pristine carbon nanotubes.

 Here, we present strategies that offer this capability. Nanoscale thermocapillary flows in thin-film organic coatings followed by reactive ion etching serve as highly efficient means for selectively removing metallic carbon nanotubes from electronically heterogeneous aligned arrays grown on quartz substrates. The low temperatures and unusual physics associated with this process enable robust, scalable operation, with clear potential for practical use. 

We carry out detailed experimental and theoretical studies to reveal all of the essential attributes of the underlying thermophysical phenomena. We demonstrate use of the purified arrays in transistors that achieve mobilities exceeding 1,000 cm2 V-1 s-1 and on/off switching ratios of ~10,000 with current outputs in the milliamp range. Simple logic gates built using such devices represent the first steps toward integration into more complex circuits.

HDD Trays & Components

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Nanocyl has recently seen a significant growth in the use of NC7000 carbon nanotubes for hard disk drives (HDD) trays and components. As data is continuously stored in ever-denser discs, the sensitivity of the components has increased dramatically. Because of this, the HDD industry has set virtually the highest cleanliness standards compared to all other industries.

Applications for CNTs:

 You will find Nanocyl Carbon Nanotubes used in a wide range of transport trays for HDD. These trays carry “Flex Suspension Assemblies” (FSA), “Head Gimbal Assemblies” (HGA), and other sensitive components. Others applications containing Nanocyl Carbon Nanotubes are VCM trays, HDD cassettes, spacer combs, air filter trays, HSA trays, and TSA/CIS suspension.

Requirements:

 In terms of surface resistivity, the transport trays need to be 1X 10^5 to 1 X 10^11 Ohm/square in size, and must meet the high level of cleanliness standards.

Also, the plastic parts that protect the components cannot be a source of ionic or metallic contaminations. High sloughing, poor abrasion resistance, and outgassing must be avoided, too, as they can lead to HDD contaminations, and can cause a decrease of the HDD performance and a decline in longevity.

Advantages of Nanocyl NC7000 Carbon Nanotubes: 

Because Nanocyl Carbon Nanotubes have a lower loading needed to reach a given resistivity in clean room devices, the probability of contaminates being in micro chips and other sensitive components is also lowered.
  • Compare this to the waste, contaminations, and inefficiencies produced by using carbon black or carbon fibers in the same applications.
  • Nanocyl Carbon Nanotubes meet the requirements for Class 100 clean rooms. A Class 100 clean room is designed to never allow more than 100 particles (0.5 microns or larger) per cubic foot of air, and must be washable.
  • Nanocyl has results from three major tests evaluating Nanocyl Carbon Nanotubes cleanliness: (1) The liquid particle count test measuring the number of particles escaping from the part via sloughing; (2) An outgassing test; and (3) An ionic and metallic contamination test.

Nanotubes - Electronic Properties

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Carbon nanotubes are drinking-straw-like structures of pure carbon with walls that can be just one atom thick. Like graphene, which is a flat carbon sheet, carbon nanotubes have a range of useful electronic properties that makes them potential building blocks for computers and other electronic devices. Indeed, carbon nanotubes, which can behave as semiconductors, have already been used to create transistors and other electronic devices that could be smaller, faster and more energy-efficient than silicon-based devices.

Researchers have also used nanotubes to create some of the components used in a computer – such as oscillators and half-adders – but integrating carbon-nanotube devices into a full-blown programmable computer that can run stored programs is far from easy. The problem is that these tubes are only a few nanometres in diameter and tens or even hundreds of them have to be placed with great precision on a substrate to create just one transistor.

Preventing Future Problems by Making Nanomaterials Greenly

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Use of non-toxic solvents :

• Self-assembly
• Use of solid state processes
• Bio-inspired nanoscale synthesis; biochemical
• Templating processes (including ambient, room-temperature processes)
• Microwave technology
• Improved synthesis, fewer toxics
• Molten Salt or Ionic Liquid Synthesis
• Solvothermal/hydrothermal Processes
• Photochemical synthesis
• Renewables in Nanocomposites
• Nano-enabled green energy systems
• Bottom up Manufacturing

How might we get to Green Nano?

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1. Aim for Sustainability:
Whether nanotechnology is green depends on individuals who have a consciousness of the values they incorporate into their work so that sustainability and green practices are paramount. This consciousness also extends to the choice to work on green projects that help lead to sustainability.

2. Don’t re-invent the whole wheel. (While much of nanotechnology is new, we can use existing tools to understand its implications.):
Toxicity data on the materials may be missing, but nevertheless, the LCA tool is applicable. We can use material flow analysis for nanomaterials in the same way we use it to examine
chemicals. These and other current industrial ecology tools can be used for nanotechnology.

3. Do not build stovepipes:
Nanotechnology is very multidisciplinary. Engineers can learn from the toxicologists; risk assessors can learn from materials scientists; industrial ecologists can learn from physicists; chemists can learn from ecologists. What we have learned in green chemistry, green engineering, and all aspects of industrial ecology can be applied.

4. Ensure that all stages of the life cycle are green.

5. Do it right the first time, or, beware of same old, same old:
Just because that old toxic chemical solvent is readily available; just because the current supplier does not make the part for a new unit process; just because materials have always behaved that way; just because you already have a piece of equipment does not mean that the approach to nanotechnology should be constrained. Green nanotechnology encourages a fresh way of designing new products, with the environment and sustainability in mind. Taking care of environmental concerns up front pays back in long-term benefits.

6. Communicate Green Nanotechnology clearly.

7. Engage in participatory governance:
Promote best practices. Become active in standards setting activities. Comment on regulations. Take part in stewardship programs. Enter into dialogues regarding responsible development of nanotechnology. Share information with policy-makers about green nanotechnology.

Green Nanotechnology

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There is a general perception that nanotechnologies will have a significant impact on developing 'green' and 'clean' technologies with considerable environmental benefits. The best examples are the use of nanotechnology in areas ranging from water treatment to energy breakthroughs and hydrogen applications. As a matter of fact, renewable energy applications probably are the areas where nanotechnology will make its first large-scale commercial breakthroughs.

Researchers agree that the safest possible future for advancing nanotechnology in a sustainable world can be reached by using green chemistry. Green chemistry means designing chemical products and processes in a way that reduces or eliminates hazardous substances from the beginning to end of a chemical product’s life cycle. The practice began in the United States with the passage of the Pollution Prevention Act of 1990, which established a national policy to prevent or reduce pollution at its source whenever feasible. Reducing pollution at the source, according to the act, "is fundamentally different and more desirable" than managing waste and controlling pollution. Since then, the EPA Green Chemistry Program has built collaborations with academia, industry, other government agencies, nongovernmental organizations and international partners to promote pollution prevention through green chemistry.

As the report "Green Nanotechnology: It's easier than you think" (pdf) states: "Green nanotechnology offers the opportunity to head off adverse effects before they occur. Green nanotechnology can proactively influence the design of nanomaterials and products by eliminating or minimizing pollution from the production of the nanomaterials, taking a life cycle approach to nanoproducts to estimate and mitigate where environmental impacts might occur in the product chain, designing toxicity out of nanomaterials and using nanomaterials to treat or remediate existing environmental problems. Green nanotechnology does not arise de novo; rather, it builds on the principles of green chemistry and green engineering and focuses them through a new lens on the unique and often counter intuitive effects that occur in nanoscale materials.

Apart from the obvious areas of using nanomaterials in the areas of solar cells, biofuels and fuel cells, green nanotechnology applications might involve a clean production process, such as synthesizing nanoparticles with sunlight or the recycling of industrial waste products into nanomaterials, such as turning diesel soot into carbon nanotubes.

Toxicology of Sophisticated Materials: Nanotoxicology and Beyond

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It has long been recognized that the physical form of materials can mediate their toxicity—the health impacts of asbestiform materials, industrial aerosols, and ambient particulate matter are prime examples. Yet over the past 20 years, toxicology research has suggested complex and previously unrecognized associations between material physicochemistry at the nanoscale and biological interactions. With the rapid rise of the field of nanotechnology and the design and production of increasingly complex nanoscale materials, it has become ever more important to understand how the physical form and chemical composition of these materials interact synergistically to determine toxicity. 

As a result, a new field of research has emerged—nanotoxicology. Research within this field is highlighting the importance of material physicochemical properties in how dose is understood, how materials are characterized in a manner that enables quantitative data interpretation and comparison, and how materials move within, interact with, and are transformed by biological systems. Yet many of the substances that are the focus of current nanotoxicology studies are relatively simple materials that are at the vanguard of a new era of complex materials. 

Over the next 50 years, there will be a need to understand the toxicology of increasingly sophisticated materials that exhibit novel, dynamic and multifaceted functionality. If the toxicology community is to meet the challenge of ensuring the safe use of this new generation of substances, it will need to move beyond “nano” toxicology and toward a new toxicology of sophisticated materials. Here, we present a brief overview of the current state of the science on the toxicology of nanoscale materials and focus on three emerging toxicology-based challenges presented by sophisticated materials that will become increasingly important over the next 50 years: identifying relevant materials for study, physicochemical characterization, and biointeractions.

Nanotoxicology and Nanoparticle Safety In Biomedical Designs

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Nanotechnology has wide applications in many fields, especially in the biological sciences and medicine. Nanomaterials are applied as coating materials or in treatment and diagnosis. Nanoparticles such as titania, zirconia, silver, diamonds, iron oxides, carbon nanotubes, and biodegradable polymers have been studied in diagnosis and treatment. 

Many of these nanoparticles may have toxic effects on cells. Many factors such as size, inherent properties, and surface chemistry may cause nanoparticle toxicity. There are methods for improving the performance and reducing toxicity of nanoparticles in medical design, such as biocompatible coating materials or biodegradable/biocompatible nanoparticles. Most metal oxide nanoparticles show toxic effects, but no toxic effects have been observed with biocompatible coatings. Biodegradable nanoparticles are also used in the efficient design of medical materials,

Nanotoxicology Specialty

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The objectives of the Nanotoxicology Specialty  are to:
  • Serve as the focal point for interaction of members of the Society of Toxicology interested in "Nanotoxicology."
  • Facilitate discussion of the appropriate design of toxicological studies for evaluating the toxicity of nanoscale materials.
  • Facilitate discussion (e.g., through symposia) of the most appropriate dosimetrics for evaluating nanoscale materials in vitro and in vivo.
  • Facilitate discussion of the most appropriate and validated screening tests for evaluating the toxicity of nanoscale materials and for extrapolating the findings from in vitro studies to in vivo exposures.
  • Facilitate discussion regarding the data required for conducting risk assessments of nanoscale materials in the future, addressing the research required to fill data-gaps.
  • Facilitate the generation of position papers and review articles by nanotoxicology experts regarding relevant subjects such as dosimetrics, metrology, in vitro toxicity, in vivo toxicity, and risk assessment.
  • Conduct educational programs and activities that emphasize current developments and issues in nanotoxicology.
  • Relate the developments in nanotoxicology to the activities of the Society of Toxicology and to the toxicology/environmental health sciences community-at-large, with the goal of stimulating interest and growth in nanotoxicology as it relates to the general science of toxicology.
  • Provide a national/international resource on matters relating to nanotoxicology.

Metallopolymer NanoComposites: Preparation and Properties

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The materials based on metal nanoparticles have found many applications in chemistry, physics and biology. The nanoscale association of inorganic colloids with polymers affords hybrid materials that combine the properties of both components. In such a way, a catalytic, optical and electronic features of inorganic colloids might be combined with the characteristics of polymers that offer many advantages in processing. The main problems in this field focus on the development of effective methods for the synthesis and stabilization of metal nanoparticles.

In this paper we consider the methods including simultaneous formation of the polymer matrix and metal nanoparticles. One of them is based on the thermal transformations of metal-containing monomers which includes dehydration, solid phase polymerization, and decomposition of the product which proceed sequentially at varied temperature ranges. The thermolysis resulted in the synthesis of metal nanoparticles with narrow size distribution (the mean particle diameter of 5-10 nm) in the polymer matrix . The topography of the initial compounds and metallopolymer composites obtained as well as their composition are analyzed by optical and electron microscopy. The initial stage of nanoparticle nucleation in metallopolymer system was studied using the EXAFS spectroscopy.

The novel approach for synthesis of noble metal polymer-immobilized catalysts via frontal polymerization of acrylamide complexes into surface of inorganic oxides is elaborated. Electron microscopy studies indicate that such polymer-inorganic composites contain Pd nanoparticles which are homogeneously distributed in the polymer matrix. The hybrid inorganic polymer nanocomposites on the base of titanium oxide and methacrylate polymers containing transition metal ions were obtained and characterized using sol-gel synthesis.

NanoBio Interfaces

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The NanoBio Interfaces Group seeks to understand how deliberate tailoring of multiphase materials at the nanoscale can lead to enhanced functionalities for energy and information transduction. We investigate fundamental parameters that govern energy conversion in functionally integrated multicomponent nanoparticle hybrid systems, capable of energy storage in the form of separated charges. The design of these novel hybrid systems for energy conversion uses nanoparticles for initial light-induced charge separation while biomolecules or inorganic matrixes are utilized for subsequent chemical/electrical conversion. We investigate the role of size, shape, and composition of nanoparticles in physical and chemical properties as well as their reactivity.

Within this program, we develop hybrid nanoparticle structures that combine the properties of different components on the nanoscale leading to new collective properties that arise from the interactions between the individual constituents. For example, we are developing quantum-dot (QD) based solid-state inorganic solutions capable of ionic conductivity, tailored for a new type of photovoltaic cells. The ionic conductive solid matrix with variable redox properties will provide high stability by efficient removal and conducting of photogenerated holes.

Facilities include organic laboratories and clean rooms designed to carry out temperature-controlled, air-free synthesis, enabling these cornerstone capabilities of the group:
  • Specialized synthesis of QDs and their assemblies
  • Probing the interface of QDs with biomolecules and solid-state matrixes
  • Incorporation of these hybrids into devices

Nanoscale Magnetic Materials and Applications

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Nanoscale Magnetic Materials and Applications covers exciting new developments in the field of advanced magnetic materials. Readers will find valuable reviews of the current experimental and theoretical work on novel magnetic structures, nanocomposite magnets, spintronic materials, domain structure and domain-wall motion, in addition to nanoparticles and patterned magnetic recording media.

Cutting-edge applications in the field are described by leading experts from academic and industrial communities. These include new devices based on domain wall motion, magnetic sensors derived from both giant and tunneling magnetoresistance, thin film devices in micro-electromechanical systems, and nanoparticle applications in biomedicine.

In addition to providing an introduction to the advances in magnetic materials and applications at the nanoscale, this volume also presents emerging materials and phenomena, such as magnetocaloric and ferromagnetic shape memory materials, which motivate future development in this exciting field.

As a subfield of nanotechnology, nanostructured magnets share many of the same basic organizing principles, such as geometric confinement, physical proximity, and chemical self organization. These principles are illustrated by means of several examples drawn from the quests for ultrastrong permanent magnets, ultrahigh-density magnetic information storage, and biomedical applications. This symposium addresses the challenges and scientific problems in magnetic nanostructures, from the fundamental issues to fabrication and applications.

Nanotechnology for Sustainable Energy Applications

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Recently, the understanding of nanotechnology has shown to play a transformative role in providing sustainable clean energy. In this context, we believe that the development of nanotechnological based research will provide technical challenges to meet the energy conversion, storage and conservation in affordable manner with control of nanomaterials, nanostructures and nanoscale phenomena. 

The super capacitor, photovoltaic, photochemical, hydrogen storage, thermal storage devices will be discussed which could provide the low cost efficient devices through the application of nanotechnology. The performance demand of super capacitor is improving by fabricating novel nanocomposite electrode by combining with processing techniques, geared towards high surface area and high metallic conductivity. Our graphite-conducting polymer or metal oxide electrodes have shown high power density cost effectively. Novel thermal energy storage materials with high rate heat capacity and compatible with any design are needed for military, commercial and solar energy applications. 

We are working on encapsulated Phase Change Material (PCM) for solar thermal energy applications. Recently, we have observed for the first time the photoelectrochemical properties of nanodiamond–ragioregular polyhexylthiophene conjugated polymer nanohybrid which is nearly 8 to 10 fold greater than most common metal oxide-conducting polymer hybrid materials. One of the biggest challenges for the commercial application of hydrogen-based energy is to find a high volumetric and gravimetric hydrogen storage capacity, the ability to be refueled quickly and repetitively and a safe transportation system. Out all the studied materials (metal hydride, carbon nanotubes, conducting polymer, etc.) have shown high hope, so emphasis is made to synthesize high surface area nanocomposite material for hydrogen storage applications.

Nanotechnology in Energy

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Nanotechnologies provide essential improvement potentials for the development of both conventional energy sources (fossil and nuclear fuels) and renewable energy sources like geothermal energy, sun, wind, water, tides or biomass. Nano-coated, wear resistant drill probes, for example, allow the optimization of lifespan and efficiency of systems for the development of oil and natural gas deposits or geothermal energy and thus the saving of costs. Further examples are high-duty nanomaterials for lighter and more rugged rotor blades of wind and tidel power plants as well as wear and corrosion protection layers for mechanically stressed components (bearings, gear boxes, etc.). Nanotechnologies will play a decisive role in particular in the intensified use of solar energy through photovoltaic systems. In case of conventional crystalline silicon solar cells, for instance, increases in efficiency are achievable by antireflection layers for higher light yield.

Energy conversion:

The conversion of primary energy sources into electricity, heat and kinetic energy requires utmost efficiency. Efficiency increases, especially in fossil-fired gas and steam power plants, could help avoid considerable amounts of carbon dioxide emissions.Higher power plant efficiencies, however, require higher operating temperatures and thus heat-resistant turbine materials. Improvements are possible, for example, through nano-scale heat and corrosion protection layers for turbine blades in power plants or aircraft engines to enhance the efficiency through increased operating temperatures or the application of lightweight construction materials (e.g. titanium aluminides).Nano-optimized membranes can extend the scope of possibilities for separation and climate-neutral storage of carbon dioxide for power generation in coal-fired power plants, in order to render this important method of power generation environmentally friendlier in the long run. The energy yield from the conversion of chemical energy through fuel cells can be stepped up by nano-structured
electrodes, catalysts and membranes, which results in economic application possibilities in automobiles, buildings and the operation of mobile electronics.

Thermoelectric energy conversion seems to be comparably promising. Nano-structured semiconductors with optimized boundary layer design contribute to increases in efficiency that could pave the way for a broad application in the utilization of waste heat, for example in automobiles, or even of human body heat for portable electronics in textiles.

Implications of Nanotechnology for Environmental Health Research

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Nanotechnology is often described as an emerging technology—one that not only holds promise for society, but also is capable of revolutionizing our approaches to common problems. Nanotechnology is not a completely new field; however, it is only recently that discoveries in this field have advanced so far as to warrant examination of their impact upon the world around us.The value of nanomaterials in many technology areas is very high because of their versatile properties. As a result, the investment in nanotechnology by the U.S. government has had a very steady growth; in 2004 investment from a range of different federal agencies
reached nearly $1 billion, noted Kenneth Olden, National Institute of Environmental Health Sciences. Industrial investment in this area is also growing steadily. Today some nanomaterials are already being used commercially. For example, some companies are using TiO2 nanoparticles in sunscreen lotions because they provide transparency to a sunscreen, and are believed to be less toxic than the organic molecules currently used as UV absorbers in many sunscreen formulations.

Nanomaterials can also be found in sporting equipment, clothing, and telecommunication infrastructure. The future of nanotechnology is boundless, according to some speakers. Some of the items that exist today were a topic of science fiction a decade ago and have the potential to transform our society very quickly, said Douglas Mulhall, author of Our Molecular Future.Nanoparticles fall into three major groups: natural, incidental, and engineered, noted Vicki Colvin, Rice University. Naturally occurring nanomaterials such as volcanic ash, ocean spray, magnetotactic bacteria, mineral composites and others exist in our environment.
Incidental nanoparticles, also refered to as waste particles, are produced as a result of some industrial processes.

The third category of nanoparticles is engineered nanoparticles—these are the particles associated with nanotechnology. Engineered nanoparticles are subclassified by the type of basic material and/or use: metals, semiconductoris, metal oxides, nanoclays, nanotubules, and quantum dots. Within each category the shapes, sizes, and surface coatings further determine structure and function of these molecules. Each such material has been specifically designed for function, such as the fullerene C60, which is used for fuel cell applications. Very little is known about engineered nanoparticles and how they interact with cells or human organisms, noted Colvin.

Implications Of Nanotechnology In Society

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Establishing an effective process for identifying and understanding the broad implications of nanotechnology for society will play a central role in making nanotechnology a success, as it will certainly affect the decisions of policymakers and regulatory agencies alike.Because truly transformative technologies have far-reaching consequences, they always generate controversy. Establishing an effective process for identifying and understanding the broad implications of nanotechnology will advance its acceptance and success, impact the decisions of policymakers and regulatory agencies, and facilitate the development of judicious policy approaches to new technology options.

Nanoscale: Issues and Perspectives for the Nano Century addresses the emerging ethical, legal, policy, business, and social issues. A compilation of provocative treatises, this reference:
  • Covers an area of increasing research and funding
  • Organizes topics in four sections: Policy and Perspectives; Nano Law and Regulation; Nanomedicine, Ethics, and the Human Condition; and Nano and Society: 
  • The NELSI Imperative Presents differing perspectives, with views from nanotechnology's most ardent supporters as well as its most vocal critics
  • Includes contributions from professionals in a variety of industries and disciplines, including science, law, ethics, business, health and safety, government regulation, and policy.
This is a core reference for professionals dealing with nanotechnology, including scientists from academia and industry, policy makers, ethicists and social scientists, safety and risk assessment professionals, investors, and others. It is also an excellent text for students in fields that involve nanotechnology.

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