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Using Carbon Nanotubes to Produce Electricity

The researchers of Massachusetts Institute of Technology (MIT) have uncovered a new phenomenon of carbon nanotubes. They found that carbon nanotubes discharge powerful waves of electricity under certain circumstances. MIT team named it as thermopower waves hp pb995a battery. They are pinning their hope on thermopower waves to produce electricity to be utilized in small electrical appliances or maybe in large-scale applications too. This project was funded by the Air Force Office of Scientific Research, and the US National Science Foundation (NSF).

This discharge of electricity from carbon nanotubes is a very rare occurrence. Traditionally we derive electricity from water, sun, wind, coal or heat produced by burning of fossil fuels. The thermopower wave, “opens up a new area of energy research, which is rare,” said Michael Stranowho is MIT’s Charles and Hilda Roddey associate professor of Chemical Engineering. His work was published in scientific journal Nature Materials.

Carbon Nanotubes are submicroscopic structures. They are just billionths of a meter in diameter. Carbon nanotubes resemble honeycombs. For the past twenty years scientists are focusing their energies on carbon nanotubes, graphene sheets and buckeyballs lenovo 3000 v100 battery. They find these three most promising for clean and green energy research. These three substances can be valuable for the medicine, nanotechnology, geoengineering, biology, and for the electronics industry.

Researchers associated with this project find the whole phenomenon quite unusual. They have observed that as the moving pulses of heat pass through the carbon naotubes, electrons also travel along. This movement of electrons is responsible for generation of electric current. Strano says, “There’s something else happening here. We call it electron entrainment since part of the current appears to scale with wave velocity.”

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Oxidation Catalysis by Pure Nano gold powder

The historical notion regarding the inability of gold to catalyze reactions has been discarded in view of recent studies, which have clearly demonstrated the high catalytic efficiency of supported nano-gold catalysts. Although nano-Au catalysts are known to catalyze a variety of reactions, the major focus has been on CO oxidation catalysis. In this work we focus on the important aspects related to the CO oxidation reaction. Special emphasis is placed on the studies undertaken on model nano-Au systems as these studies have considerably enhanced the understanding of the oxidation process. Pure Nano gold powder in a highly dispersed state can selectively oxidize CO in the presence of excess hydrogen (of tremendous interest to state-of-the-art low-temperature fuel cells); related studies are addressed in this review. The nano-gold catalysts have also been investigated for the direct vapor-phase oxidation of propylene to propylene oxide in the presence of molecular oxygen; these investigations are highlighted in this work.
Gold nano-particles confined in the walls of mesoporous silica (GMS) catalysts were successfully prepared by a novel and simple technique utilizing thioether functional groups in the walls of mesoporous silica to anchor HAuCl4. Calcination of the materials removed organic moieties and reduced the gold salt to gold nano-particles. In this procedure, the thioether groups were introduced into the silica wall via a co-condensation of tetraethyl orthosilicate (TEOS) with 1,4-bis(triethoxysily)propane tetrasulfide. These gold containing mesoporous catalysts have unusually high surface area and pore volume.
The catalysts were evaluated for the solvent free liquid phase oxidation of benzyl alcohol by molecular oxygen. High selectivity to benzaldehyde was obtained under the reaction conditions of 403 K, 15 atm and 5 h in an autoclave. The 1.5% GMS catalyst was also evaluated for oxidation of alcohols using toluene as solvent under flowing oxygen at atmospheric pressure at 353 K in a two-necked flask. Under these conditions the conversion of benzyl alcohol reached 100% after 2 h and it was demonstrated that the catalyst can be recycled three times without significant loss of activity.

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Chromium nanoparticles and morphology

Several concentrations of adsorbent and adsorbate were tested, trying to cover a large range of possible real conditions. Results showed that the Freundlich isotherm represented well the adsorption equilibrium reached between nanoparticles and chromium, whereas adsorption kinetics could be modeled by a pseudo-second-order expression. The separation of chromium–cerium nanoparticles from the medium and the desorption of chromium using sodium hydroxide without cerium losses was obtained. Nanoparticles agglomeration and morphological changes during the adsorption–desorption process were observed by TEM.

Chromium nanoparticles and morphology changes during the process
In this study, suspended cerium oxide nanoparticles stabilized with hexamethylenetetramine were used for the removal of dissolved chromium VI in pure water.

Another remarkable result obtained in this study is the low toxicity in the water treated by nanoparticles measured by the Microtox® commercial method. These results can be used to propose this treatment sequence for a clean and simple removal of drinking water or wastewater re-use when a high toxicity heavy metal such as chromium VI is the responsible for water pollution.
ZnO and Cr doped ZnO nanoparticles were synthesized by chemical vapor synthesis (CVS) which is a modified chemical vapor deposition (CVD) process. The resulting powders consist of nanocrystalline particles and were characterized by X-ray diffraction (XRD), nitrogen adsorption (BET), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), element analysis, and extended X-ray absorption fine structure (EXAFS) spectroscopy. The grain size decreases with increasing dopant concentration. The lattice constants extracted by the Rietveld method from XRD data vary slightly with doping concentration. XRD and EXAFS data analysis show that the Chromium dopant atoms are incorporated into the wurtzite host lattice.

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Synthesis of Metal Alloy Nanoparticles

A simple, convenient, and general method for the synthesis of metal and metal alloy nanoparticles is presented. Irradiation of metal powders in suspension in either aqueous or organic solutions by unfocused 532 nm laser radiation produces nanoparticles with a homogeneous composition proportional to the composition of the starting metal powder mixture. This is demonstrated using UV−vis absorption spectroscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, and modelization. The mechanism of alloy formation is discussed.
This Review is focused on the recent progresses in the synthetic approaches to the precise control of structure, size, shape, composition and multi-functionality of metal and metal alloy nanoparticles. Many of these strategies have been developed based on colloidal methods, and to limited extent, the galvanic and other methods.

Synthesis of Metal Alloy Nanoparticles in Solution by Laser Irradiation of a Metal Powder Suspension. The shape, size and composition often govern the chemical and catalytic properties that are important for electrochemical energy applications. The structure–property relationship and the design in controllable structures and morphologies for specific reactions such as oxygen reduction reaction (ORR) are emphasized.Magnetic nanoparticles have potential applications in high-density memory devices, but their complicated synthesis often requires high temperatures, expensive reagents, and postsynthesis annealing to achieve the desired magnetic properties. Current synthetic methods for magnetic nanoparticles often require post-synthetic modifications, suggesting that the practical application of magnetic nanoparticles will depend on the development of alternative synthetic strategies.
We report a biological template to directly grow magnetic nanoparticles of desired material composition and phase under ambient conditions. A phage display methodology was adapted to identify peptide sequences that both specifically bind to the ferromagnetic L10 phase of FePt and control the crystallization of FePt nanoparticles using a modified arrested precipitation technique.

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Nano Element Particles on Dispersing in ODS Steel

From the irradiation resistance and high-temperature strength, oxide dispersion strengthened (ODS) ferritic steels are candidate materials for advanced and fusion reactors. For the development of advanced steels the key issue is to homogenize nano-particles into matrix. Recent studies have indicated that Ti addition can homogenize Y-Ti complex particles into ferrite matrix, but the reason of the effect of additional elements has not been clarified. In this model study, we focus on the effect of additional elements, such as IV and V families and other oxide formers, which can control potentially the distribution of the oxide particles.

The materials used in this study were based on Fe-9Cr-Y2O3 alloys which were mechanical alloyed (MA) from the powder of Fe, Cr and Y2O3, which was added systematically with the element of Ti, Zr, Ta, V, Nb, Hf, Al, Si and others. Usually ODS fabrication process is required for hot extrusion, but we annealed up to 1150 C for simplify the microstructure. To evaluate the distribution of ODS Nano Element Particles ; we used TEM equipped with EDS after electro-polishing or FIB techniques.

(1) In the case of Si or Al addition, oxides were disappeared after MA process, which means Y2O3 and other elements should be in solution at non-equilibrium condition. Two types of oxides of Y2O3 and Al2O3 or SiO2 developed after the annealing at 850 C,b> developed after the annealing at 850 C, but only complex oxides were developed after the annealing at 1150 C. This result suggests that the oxide formation is independent process for Y and Si or Al. (2) In the case of Ti addition, oxides also were disappeared after MA process, but developed after annealing at 1150 C. This means that Ti can stabilize complex oxides of Y and Ti, and enhance the fine distribution of the oxides comparing with simple Fe-9Cr-Y2O3 alloy.