Wednesday, February 29, 2012

Amazing renewable hydrogen and natural gas using: sun + CO2 +H20

Amazing renewable hydrogen and natural gas using: sun + CO2 +H20
The technology HyperSolar is developing is extraordinary -- using the sun and carbon dioxide and water to create renewable hydrogen and natural gas. How does the technology work?
HyperSolar, Inc. with the University of California, Santa Barbara describes its process as inspired by photosynthesis where by plants use the sun's energy for fuel. To replicate this, the Santa Barbara-based company is "developing a novel solar-powered nanoparticle system that mimics photosynthesis to separate hydrogen from water. The free hydrogen can then be reacted with carbon dioxide to produce methane."

Something like this:
2H20-->2H2 + O2
2H2 + CO2 --> CH4 + O2
And then.. burn it!
CH4 + 2O2 + heat --> CO2 + 2H20 + energy

"If this were not enough "the company is developing a process to use wastewater in place of pure water. In this case, not only will the water come at no cost but it will also leave the process clean"
“UCSB is world renown for its scientific accomplishments. “We are very excited about this opportunity to gain access to the talents and state-of-the-art facilities of one of the world’s top universities for scientific impact,” he said.
Natural gas is becoming an increasingly hot topic in the U.S. As the country debates the environmental impact of extracting the fuel from beneath the earth's surface, President Obama is throwing his support at expanding the natural gas infrastructure."


I hope that here in Mexico could pay more attention to environmental issues and sustainable energy. So, little by little, become less dependent on oil


Find more information on this work in the UCSB website: http://www.nanotech.ucsb.edu/index.php?option=com_content&view=article&id=95:rie-2-methane-hydrogen-based-system
Notice source: http://www.energyboom.com/biofuels/hypersolar-teams-ucsb-develop-renewable-hydrogen-natural-gas-technology


Monday, February 27, 2012

Crystallization Pathway in the Bulk Metallic Glass Zr41.2Ti13.8Cu12.5Ni10Be22.5

A new family of multicomponent metallic alloys exhibits an excellent glass forming ability at moderate cooling rates of about 10K/s and a wide supercooled liquid region. These glasses are eutectic or nearly eutectic, thus far away from the compositions of competing crystalline phases. The nucleation of crystals from the homogeneous amorphous phase requires large thermally activated composition fluctuations for which the time scale is relatively long, even in the supercooled liquid.

In the Zr41.2Ti13.8Cu12.5Ni10Be22.5 alloy therefore a different pathway to crystallization is observed. The initially homogeneous alloy separates into two amorphous phases. In the decomposed regions, crystallization probability increases and finally polymorphic crystallization occurs.


Reference
S. Schneider, P. Thiyagarajan, U. Geyer and W. L. Johnson (1996). Crystallization Pathway in the Bulk Metallic Glass Zr41.2Ti13.8Cu12.5Ni10Be22.5. MRS Proceedings, 455 , 295 doi:10.1557/PROC-455-295

Cavitation bubbles

A research team at standford university is currently working in ArF lasser technics to induce cavitation in a gel surrounded by a liquid medium that might be used later in biological tissue. This is a great breakthrough for medicine since it could be used not only for regular surgery with more precision, but it could be used to eliminate cancer cells too. In the following link, is a full description of the research of standford´s research team: http://www.stanford.edu/~palanker/publications/excimer%20laser%20in%20gel.pdf

For more information about cavitation, I recomend the next video, which describe in a brief and easy way, what cavitation and cavitation bubbles are, and some possible applications for this.

Helio!

http://www.youtube.com/watch?v=tzecE6XDFgg&feature=BFa&list=UUZYTClx2T1of7BRZ86-8fow&lf=plcp

En el vídeo anterior se exponen algunas características y usos generales del helio, y también se habla sobre el inevitable déficit de helio al que los acercamos. A continuación se expone una breve historia del helio y sus usos.

"Helium, the second most abundant element in the universe, was discovered on the sun before it was found on the earth. Pierre-Jules-César Janssen, a French astronomer, noticed a yellow line in the sun's spectrum while studying a total solar eclipse in 1868. Sir Norman Lockyer, an English astronomer, realized that this line, with a wavelength of 587.49 nanometers, could not be produced by any element known at the time. It was hypothesized that a new element on the sun was responsible for this mysterious yellow emission. This unknown element was named helium by Lockyer.
The hunt to find helium on earth ended in 1895. Sir William Ramsay, a Scottish chemist, conducted an experiment with a mineral containing uranium called clevite. He exposed the clevite to mineral acids and collected the gases that were produced. He then sent a sample of these gases to two scientists, Lockyer and Sir William Crookes, who were able to identify the helium within it. Two Swedish chemists, Nils Langlet and Per Theodor Cleve, independently found helium in clevite at about the same time as Ramsay.
Helium makes up about 0.0005% of the earth's atmosphere. This trace amount of helium is not gravitationally bound to the earth and is constantly lost to space. The earth's atmospheric helium is replaced by the decay of radioactive elements in the earth's crust. Alpha decay, one type of radioactive decay, produces particles called alpha particles. An alpha particle can become a helium atom once it captures two electrons from its surroundings. This newly formed helium can eventually work its way to the atmosphere through cracks in the crust.
Helium is commercially recovered from natural gas deposits, mostly from Texas, Oklahoma and Kansas. Helium gas is used to inflate blimps, scientific balloons and party balloons. It is used as an inert shield for arc welding, to pressurize the fuel tanks of liquid fueled rockets and in supersonic windtunnels. Helium is combined with oxygen to create a nitrogen free atmosphere for deep sea divers so that they will not suffer from a condition known as nitrogen narcosis. Liquid helium is an important cryogenic material and is used to study superconductivity and to create superconductive magnets. The Department of Energy's Jefferson Lab uses large amounts of liquid helium to operate its superconductive electron accelerator."

For further reading:
"U.S. government agencies work to minimize damage due to helium-3 shortfall," Toni Feder, Physics Today October 2009, page 21
http://www.physicstoday.org/resource/1/phtoad/v62/i10/p21_s1?isAuthorize...
"Nation's helium reserve running on empty?" Leslie Tamura, Washington Post, Oct.11, 2010
http://education.jlab.org/itselemental/ele002.html

De lo mismo de abajo: Paint-On Solar Cells Developed

Imagine if the next coat of paint you put on the outside of your home generates electricity from light -- electricity that can be used to power the appliances and equipment on the inside.

A team of researchers at the University of Notre Dame has made a major advance toward this vision by creating an inexpensive "solar paint" that uses semiconducting nanoparticles to produce energy.

"We want to do something transformative, to move beyond current silicon-based solar technology," says Prashant Kamat, John A. Zahm Professor of Science in Chemistry and Biochemistry and an investigator in Notre Dame's Center for Nano Science and Technology (NDnano), who leads the research.

"By incorporating power-producing nanoparticles, called quantum dots, into a spreadable compound, we've made a one-coat solar paint that can be applied to any conductive surface without special equipment."

The team's search for the new material, described in the journal ACS Nano, centered on nano-sized particles of titanium dioxide, which were coated with either cadmium sulfide or cadmium selenide. The particles were then suspended in a water-alcohol mixture to create a paste.

When the paste was brushed onto a transparent conducting material and exposed to light, it created electricity.

"The best light-to-energy conversion efficiency we've reached so far is 1 percent, which is well behind the usual 10 to 15 percent efficiency of commercial silicon solar cells," explains Kamat.

"But this paint can be made cheaply and in large quantities. If we can improve the efficiency somewhat, we may be able to make a real difference in meeting energy needs in the future."

"That's why we've christened the new paint, Sun-Believable," he adds.

Kamat and his team also plan to study ways to improve the stability of the new material.

NDnano is one of the leading nanotechnology centers in the world. Its mission is to study and manipulate the properties of materials and devices, as well as their interfaces with living systems, at the nano-scale.

This research was funded by the Department of Energy's Office of Basic Energy Sciences.

References:
University of Notre Dame (2011, December 21). Paint-on solar cells developed. ScienceDaily. Retrieved February 27, 2012, from

Sun-Believable Solar Paint. A Transformative One-Step Approach for Designing Nanocrystalline Solar Cells

Este está bien coqueto :D
Abstract Image
A transformative approach is required to meet the demand of economically viable solar cell technology. By making use of recent advances in semiconductor nanocrystal research, we have now developed a one-coat solar paint for designing quantum dot solar cells. A binder-free paste consisting of CdS, CdSe, and TiO2 semiconductor nanoparticles was prepared and applied to conducting glass surface and annealed at 473 K. The photoconversion behavior of these semiconductor film electrodes was evaluated in a photoelectrochemical cell consisting of graphene–Cu2S counter electrode and sulfide/polysulfide redox couple. Open-circuit voltage as high as 600 mV and short circuit current of 3.1 mA/cm2 were obtained with CdS/TiO2–CdSe/TiO2 electrodes. A power conversion efficiency exceeding 1% has been obtained for solar cells constructed using the simple conventional paint brush approach under ambient conditions. Whereas further improvements are necessary to develop strategies for large area, all solid state devices, this initial effort to prepare solar paint offers the advantages of simple design and economically viable next generation solar cells.

References:

Sun-Believable Solar Paint. A Transformative One-Step Approach for Designing Nanocrystalline Solar Cells

Matthew P. Genovese, Ian V. Lightcap, and Prashant V. Kamat
ACS Nano 2012 6 (1), 865-872 [Online] http://pubs.acs.org/doi/abs/10.1021/nn204381g

Nanoscale Plasmonic Interferometers for Multispectral, High-Throughput Biochemical Sensing

Abstract Image

Report the design, fabrication, and characterization of novel biochemical sensors consisting of nanoscale grooves and slits milled in a metal film to form two-arm, three-beam, planar plasmonic interferometers. By integrating thousands of plasmonic interferometers per square millimeter with a microfluidic system, we demonstrate a sensor able to detect physiological concentrations of glucose in water over a broad wavelength range (400–800 nm). A wavelength sensitivity between 370 and 630 nm/RIU (RIU, refractive index units), a relative intensity change between 103 and 106 %/RIU, and a resolution of 3 × 10–7 in refractive index change were experimentally measured using typical sensing volumes as low as 20 fL. These results show that multispectral plasmonic interferometry is a promising approach for the development of high-throughput, real-time, and extremely compact biochemical sensors.

References:

Nanoscale Plasmonic Interferometers for Multispectral, High-Throughput Biochemical Sensing

Jing Feng, Vince S. Siu, Alec Roelke, Vihang Mehta, Steve Y. Rhieu, G. Tayhas R. Palmore, and Domenico Pacifici
Nano Letters 2012 12 (2), 602-609 [on line] http://pubs.acs.org/doi/abs/10.1021/nl203325s

Water Oxidation Catalysis: Influence of Anionic Ligands upon the Redox Properties and Catalytic Performance of Mononuclear Ruthenium Complexes

Abstract Image
Aiming at highly efficient molecular catalysts for water oxidation, a mononuclear ruthenium complex RuII(hqc)(pic)3 (1; H2hqc = 8-hydroxyquinoline-2-carboxylic acid and pic = 4-picoline) containing negatively charged carboxylate and phenolate donor groups has been designed and synthesized. As a comparison, two reference complexes, RuII(pdc)(pic)3 (2; H2pdc = 2,6-pyridine-dicarboxylic acid) and RuII(tpy)(pic)3 (3; tpy = 2,2′:6′,2″-terpyridine), have also been prepared. All three complexes are fully characterized by NMR, mass spectrometry (MS), and X-ray crystallography. Complex 1 showed a high efficiency toward catalytic water oxidation either driven by chemical oxidant (CeIV in a pH 1 solution) with a initial turnover number of 0.32 s–1, which is several orders of magnitude higher than that of related mononuclear ruthenium catalysts reported in the literature, or driven by visible light in a three-component system with [Ru(bpy)3]2+ types of photosensitizers. Electrospray ionization MS results revealed that at the RuIII state complex 1 undergoes ligand exchange of 4-picoline with water, forming the authentic water oxidation catalyst in situ. Density functional theory (DFT) was employed to explain how anionic ligands (hqc and pdc) facilitate the 4-picoline dissociation compared with a neutral ligand (tpy). Electrochemical measurements show that complex 1 has a much lower E(RuIII/RuII) than that of reference complex 2 because of the introduction of a phenolate ligand. DFT was further used to study the influence of anionic ligands upon the redox properties of mononuclear aquaruthenium species, which are postulated to be involved in the catalysis cycle of water oxidation.
References:

Water Oxidation Catalysis: Influence of Anionic Ligands upon the Redox Properties and Catalytic Performance of Mononuclear Ruthenium Complexes (27 de Febrero)

Lianpeng Tong, Ying Wang, Lele Duan, Yunhua Xu, Xiao Cheng, Andreas Fischer, Mårten S. G. Ahlquist, and Licheng Sun

Inorganic Chemistry Article ASAP [Online] http://pubs.acs.org/doi/abs/10.1021/ic201348u

Sunday, February 26, 2012

Detection of Charge Storage on Molecular Thin Films of Tris(8-hydroxyquinoline) Aluminum (Alq3) by Kelvin Force Microscopy: A Candidate System for Hig

Abstract Image
Retention and diffusion of charge in tris(8-hydroxyquinoline) aluminum (Alq3) molecular thin films are investigated by injecting electrons and holes via a biased conductive atomic force microscopy tip into the Alq3 films. After the charge injection, Kelvin force microscopy measurements reveal minimal changes with time in the spatial extent of the trapped charge domains within Alq3 films, even for high hole and electron densities of >1012 cm–2. We show that this finding is consistent with the very low mobility of charge carriers in Alq3 thin films (<10–7 cm2/(Vs)) and that it can benefit from the use of Alq3 films as nanosegmented floating gates in flash memory cells. Memory capacitors using Alq3 molecules as the floating gate are fabricated and measured, showing durability over more than 104 program/erase cycles and the hysteresis window of up to 7.8 V, corresponding to stored charge densities as high as 5.4 × 1013 cm–2. These results demonstrate the potential for use of molecular films in high storage capacity nonvolatile memory cells.

Reference:

Detection of Charge Storage on Molecular Thin Films of Tris(8-hydroxyquinoline) Aluminum (Alq3) by Kelvin Force Microscopy: A Candidate System for High Storage Capacity Memory Cells ( 27 de febrero)

Sarah Paydavosi, Katherine E. Aidala, Patrick R. Brown, Pouya Hashemi, Geoffrey J. Supran, Timothy P. Osedach, Judy L. Hoyt, and Vladimir Bulović
Nano Letters Article ASAP [online] http://pubs.acs.org/doi/abs/10.1021/nl203696v

LABORATORIOS DE FÍSICA DE PARTÍCULAS MÁS IMPORTANTES DEL MUNDO.

CERN (European Organization for Nuclear Research)

Es el mayor centro de física de partículas del mundo. Fue fundado en 1954. De los 12 países que firmaron originariamente se ha pasado a 20 miembros en la actualidad: Alemania, Austria, Bélgica, Bulgaria, Dinamarca, España, Finlandia, Francia, Grecia, Holanda, Hungría, Italia, Noruega, Polonia, Portugal, Reino Unido, República Checa, República Eslovaca, Suecia y Suiza. Está situado en la frontera entre Francia y Suiza, a las afueras de Ginebra. En el CERN hay unos 3000 empleados; además 6500 científicos, la mitad de los físicos de partículas del mundo, acuden al CERN para realizar sus investigaciones. Estos científicos representan a 500 universidades y más de 80 nacionalidades. En el CERN se realizan dos tipos de experimentos: de blancos fijos y de haces que colisionan. El mayor acelerador del CERN (LEP) mide 27 km. de perímetro y está situado en un túnel a 100 m bajo tierra. Las partículas, que en él se aceleran hasta velocidades cercanas a la de la luz, rodean el acelerador más de 11000 veces por segundo. Actualmente se está construyendo en el CERN un nuevo acelerador, el gran colisionador de hadrones LHC.

FERMILAB (Fermi National Accelerator Laboratory)

Situado en Batavia (cerca de Chicago), Illinois. Fue fundado en 1967 con el nombre National Accelerator Laboratory. Se trata del mayor laboratorio de física de altas energías de Estados Unidos y el segundo mayor del mundo después del CERN. El TEVATRON del FERMILAB es el acelerador y colisionador de partículas de mayor energía del mundo. (Tanto el quark bottom como el quark top fueron descubiertos en el FERMILAB). En este laboratorio trabajan aproximadamente 2200 personas, incluyendo estudiantes colaboradores. Además tiene unos 2300 investigadores invitados de otras instituciones. El presupuesto anual del FERMILAB es de 297M $ y los costes son de 304M $ anuales.

SLAC (Stanford Linear Accelerator Center)

Fue fundado en 1962, está situado en la Universidad de Stanford en California. Científicos del SLAC han obtenido tres premios Nobel de física. Recibe a 3000 investigadores visitantes de universidades y laboratorios americanos e internacionales. El centro está operado por la Universidad de Stanford para el Departamento de Energía de los Estados Unidos.

DESY (Deutsches Elektronen Synchrotron)

Situado en Hamburgo y en Zeuthen, fue fundado en Hamburgo en 1959. Está financiado por los Ministerios de Ciencia, Educación e Investigación. En este laboratorio se han construido varios dispositivos aceleradores y colisionadores: DESY, DORIS, PETRA (en el cual se descubrieron los gluones), HASYLAB, HERA. En Hamburgo trabajan 1390 personas y en Zeuthen 170. El presupuesto anual de DESY es de aproximadamente 300M DM.

LBNL (Ernest Orlando Lawrence Berkeley National Laboratory)

Está situado en la Universidad de California en Berkeley. Se trata del laboratorio nacional de América más antiguo. Fue fundado en 1931 por Ernest Orlando Lawrence, inventor del ciclotrón. Científicos de la LBNL han sido galardonados con nueve premios Nobel (cinco de física y cuatro de química), uno de los cuales fue para su fundador. En el laboratorio trabajan 4000 empleados, 800 de los cuales son estudiantes. Además cada año recibe a 2000 investigadores invitados. El LBNL está gestionado por la Universidad de California para el Departamento de Energía de los Estados Unidos, del cual recibe los fondos para su financiación. En el LBNL se construyó el acelerador ALS (el cual produce la luz ultravioleta y rayos X más intensos del mundo) y el centro de computación científica NERSC, el más potente del país.

ESRF (European Synchrotron Radiation Facility)

Situado en Grenoble, Francia. Se trata de un instituto de investigación multinacional, actualmente con 16 países asociados. Fue fundado en 1988. El personal que trabaja en el ESRF, unas 500 personas, pertenece en su mayoría a alguno de los países asociados. El presupuesto anual del ESRF es de 420M de francos franceses.

Hay más laboratorios, para mayor información clic en link:

http://www.madrimasd.org/cienciaysociedad/ateneo/dossier/particulas/cdti/lab.pdf

:D

New metallic glass beats steel as the toughest, strongest material yet


The development of new materials has always been a need to improve our quality of life. Hence, several researchers working on new materials for the tools and technology that will lead to greater progress.Materials scientists in California have made a special metallic glass with a strength and toughness greater than any known material, using a recipe that could yield a new method for materials fabrication. The glass, a microalloy made of palladium, has a chemical structure that counteracts the inherent brittleness of glass but maintains its strength. It’s not very dense and it is more lightweight than steel, with comparable heft to an aluminum or titanium alloy.

It's true, some tougher materials exist, but they are less strong; there are stronger materials, but they’re not as tough. To grasp this, you have to define the the difference between strength and toughness. Strength refers to how much force a material can take before it deforms. Toughness explains the energy required to fracture or break something; it describes an object’s ability to absorb energy. Most of the time, these qualities are mutually exclusive. Ideal structural materials are both strong and tough; steel is a good example. The new glass has a far better combination of strength and toughness than any steel.

The glass has been obtained and described features, but still very expensive in their manufacture, but the methods to create new materials is a reality that will lead to significant improvements of tools and so further development in the world of science and technology.

Reference
POPSCI. New metal glass beats steel as the thoughest, strongest material yet. Online (http://www.popsci.com/technology/article/2011-01/new-metallic-glass-toughest-strongest-material-yet)

Monday, February 20, 2012

Future and actual applications of carbon nanotubes

Carbon nanotubes, similar to small graphite coiled sheets with nanometric diameters and lengths about microns, constitute a unique material with exceptional mechanical, electrical, optical, thermal and chemical properties which make them suitable to improve numerous already existing products and to even generate other new ones. Many are the applications that can take advantage of the properties of carbon nanotubes. Composite materials reinforced with nanotubes, flat screens that use the nanotubes as field emitters, biological and chemical sensors used to detect polluting substances, drug administration or fuel cells are only some of them. In general, sectors like electronics, materials, sensors, biotechnology, chemistry, energy, mechanics, scientific instrumentation and photonics could get many advantages from the introduction of carbon nanotubes in many of their products.

The yearly ascending tendency in the number of publications that treat of carbon nanotube applications shows the great interest existing about them. EE.UU. is the world-wide leader in number of publications, but Asia is also an important region, partly due to the presence in it of very important electronic companies which can obtain great benefits when incorporating carbon nanotubes to their products. Although Europe appears in third place in number of publications, its contribution to the research and development of carbon nanotube applications is also very important, clearly betting on these new technologies.

The market of carbon nanotube applications is still very incipient. Only composite materials reinforced with nanotubes appear in sport accessories like tennis rackets or bicycles. Electronic applications are very promising since carbon nanotubes will allow them to continue with the progressive miniaturization typical of this area which is at present threatened by the physical limits of operation of silicon, near to be reached. Nevertheless there are only electronic prototypes that incorporate carbon nanotubes, there are no commercial products due to the lack of suitable industrial processes for their elaboration. The other technologies that incorporate carbon nanotubes show different degrees of maturity in their access to the market, but they are not commercialized yet. Carbon nanotubes appear like an interesting alternative for the manufacturers of multiple products who are interested in innovating, since they promise to produce incredible benefits and to revolutionize the market when they burst into it.

Reference:

Rivas Martínez, María Jesús; Román Ganzer, José; y Cosme Huertas, María Luisa. Aplicaciones actuales y futuras de los nanotubos de carbono. Informe de vigilancia tecnológica. Vt miod 11.



Materiales extraordinarios para aplicaciones fotovoltáicas

Por Ricardo Capilla Vilchis Ciudad de México. 20 de noviembre de 2017 (Agencia Informativa Conacyt).- El aprovechamiento de la energía ...