Patrut A.,Babes - Bolyai University |
Von Reden K.F.,Mailstop 8 |
Mayne D.H.,Baobab Trust |
Lowy D.A.,Flexel Inc. |
Patrut R.T.,Babes - Bolyai University
Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms | Year: 2013
The Glencoe baobab, a very large specimen from South Africa, split twice in 2009. Several wood samples were collected from the eastern cavity, from the outer part of the main section and also from the largest broken segment which was connected to this section. These wood samples were processed and investigated by AMS radiocarbon dating. The radiocarbon date of the oldest sample was found to be 1838 ± 21 BP, which corresponds to a calibrated age of 1835 ± 40 years. Thus, the Glencoe baobab becomes the oldest dated baobab and also the oldest angiosperm tree with accurate dating results. The distribution of dating results revealed that the Glencoe baobab is a multi-generation tree, with several standing or collapsed and partially fused stems, showing different ages. © 2012 Elsevier B.V. All rights reserved.
Sorescu M.,Duquesne University |
Bushunow V.,Duquesne University |
Diamandescu L.,National Institute of Materials Physics Bucharest |
Tolea F.,National Institute of Materials Physics Bucharest |
And 3 more authors.
Ceramics International | Year: 2014
xLi2O-(1-x)α-Fe2O3 (x=0.1, 0.3, 0.5, and 0.7) nanoparticle systems were successfully synthesized by mechanochemical activation of Li2O and α-Fe2O3 mixtures for 0-12 h of ball milling time. The study aims at exploring the formation of magnetic oxide semiconductors at the nanoscale, which is of crucial importance for catalysis, sensing and electrochemical applications. X-ray powder diffraction (XRD), Mössbauer spectroscopy and magnetic measurements were used to study the phase evolution of xLi2O-(1-x)α-Fe 2O3 nanoparticle systems under the mechanochemical activation process. Rietveld refinement of the XRD patterns yielded the values of the particle size as function of composition and milling times and indicated the presence of Li-substituted hematite and tetra lithium iron oxide LiFeO 2, along with the formation of multiple phases for large x values and long milling times. The Mössbauer studies showed that the spectrum of the mechanochemically activated composites evolved from a sextet for hematite to sextets and a doublet upon duration of the milling process with lithium oxide. Magnetic measurements recorded at 5 K to room temperature (RT) in an applied magnetic field of 50,000 Oe showed that the magnetization of the milled samples is larger at low temperatures than at RT and increases with decreasing particle size. Zero field cooling measurements made possible the determination of the blocking temperatures of the specimens as function of ball milling time and evidenced the occurrence of superparamagnetism in the studied samples. This result correlates well with the observed presence of a quadrupole-split doublet in the Mössbauer spectra. © 2013 Elsevier Ltd and Techna Group S.r.l.
Agency: Department of Homeland Security | Branch: | Program: SBIR | Phase: Phase I | Award Amount: 99.96K | Year: 2009
Hydrated ruthenium oxide has demonstrated outstanding volumetric charge storage capability. It is non-toxic, environmentally safe, and when used with an oxidizing counter-electrode, becomes part of a galvanic cell (a battery). Ruthenium oxide and many oxidizing metals, like zinc, are available as nano-particulate powers. They combine to form highly flexible batteries with excellent current sourcing capabilities. We have built a thin film battery with the highest reported current density of any thin film cell. The major barrier to acceptance of this material system is cost. In the past, 1 m2 of the battery material could cost one hundred thousand dollars. We propose a manufacturing technique that can lower costs to less than one hundred dollars per m2. It is based on a coating approach that forms continuous layers of nano-particles whose thickness is close to that of a single nano-particle diameter. Thin, coated sheets can be pulled through the coater at a rate of meters squared a minute. The resulting sheets are easily assembled into mechanically flexible batteries or capacitors. The goal of the proposed program is to create a wearable battery cloth capable of powering first responder gear for times much longer than that of a typical responder mission.
Flexel Inc. | Date: 2011-04-28
An electrochemical energy cell has a galvanic cell including an anode electrode unit, a cathode electrode unit, an electrolyte body between the anode and cathode electrode units and contacting both the anode and cathode electrode units, and a separator layer including the electrolyte body and placed within the cell to contact both the anode and cathode electrode units to bring the anode and cathode electrode units in contact with the electrolyte body. The cathode electrode unit includes a cathode material including a powder mixture of a powder of hydrated ruthenium oxide and one or more additives. The anode electrode unit includes a structure formed of an oxidizable metal, and the separator layer includes a material that is porous to ions in liquid and is electrically non-conductive. A flexible electrochemical cell can be configured for a reduction-oxidation reaction to generate power at a surface of the electrode unit(s).
Flexel Inc. | Date: 2012-11-01
Systems for batteries or galvanic cells are disclosed. The system comprises a mixing chamber. The system further comprises a first reservoir, in fluid communication with a mixing chamber, the first reservoir configured to store a concentrated electrolyte. Additionally the system comprises a pump configured to pump a fluid into the mixing chamber. The system further comprises an electrochemical energy cell in fluid communication with the mixing chamber wherein the mixing chamber is configured to receive the fluid and concentrated electrolyte and mix the fluid and the concentrated electrolyte to produce a diluted electrolyte. Finally the system comprises the electrochemical energy cell configured to receive the diluted electrolyte, use the received diluted electrolyte for an electrochemical reaction and remove the used electrolyte solution from the cell.