The FIELDS Instrument Suite for Solar Probe Plus: Measuring the Coronal Plasma and Magnetic Field, Plasma Waves and Turbulence, and Radio Signatures of Solar Transients.

NASA's Solar Probe Plus (SPP) mission will make the first in situ measurements of the solar corona and the birthplace of the solar wind. The FIELDS instrument suite on SPP will make direct measurements of electric and magnetic fields, the properties of in situ plasma waves, electron density and temperature profiles, and interplanetary radio emissions, amongst other things. Here, we describe the scientific objectives targeted by the SPP/FIELDS instrument, the instrument design itself, and the instrument concept of operations and planned data products

German Medical Science ausgezeichnet

German Medical Science - das medizinische Publikationsportal von AWMF, DIMDI und ZB MED - wird am 21. Oktober 2011 von der Initiative "Deutschland - Land der Ideen" als "Ausgewählter Ort im Land der Ideen 2011" ausgezeichnet

Gram-Scale, Low Temperature, Sonochemical Synthesis of Stable Amorphous Ti–B Powders Containing Hydrogen

Gram-Scale, Low Temperature, Sonochemical Synthesis of Stable Amorphous Ti–B Powders Containing Hydroge

AgNa(VO₂F₂)₂: A Trioxovanadium Fluoride with Unconventional Electrochemical Properties

We present structural and electrochemical analyses of a new double-wolframite compound: AgNa­(VO₂F₂)₂ or SSVOF. SSVOF is fully ordered and displays electrochemical characteristics that give insight into electrode design for energy storage beyond lithium-ion chemistries. The compound contains trioxovanadium fluoride octahedra that combine to form one-dimensional chain-like basic building units, characteristic of wolframite (NaWO₄). The 1D chains are stacked to create 2D layers; the cations Ag⁺ and Na⁺ lie between these layers. The vanadium oxide-fluoride octahedra are ordered by the use of cations (Ag⁺, Na⁺) that differ in polarizability. In the case of sodium-ion batteries, thermodynamically, the use of a sodium anode introduces a 300 mV loss in overall cell voltage as compared to a lithium anode; however, this can be counter-balanced by introduction of fluoride into the framework to raise the reduction potentials via an inductive effect. This allows sodium-ion batteries to have comparable voltages to lithium systems. With SSVOF as a baseline compound, we have identified new materials design rules for emerging sodium-ion systems that do not apply to lithium-ion systems. These strategies can be applied broadly to provide materials of interest for fundamental structural chemistry and appreciable voltages for sodium-ion electrochemistry

AgNa(VO₂F₂)₂: A Trioxovanadium Fluoride with Unconventional Electrochemical Properties

We present structural and electrochemical analyses of a new double-wolframite compound: AgNa­(VO₂F₂)₂ or SSVOF. SSVOF is fully ordered and displays electrochemical characteristics that give insight into electrode design for energy storage beyond lithium-ion chemistries. The compound contains trioxovanadium fluoride octahedra that combine to form one-dimensional chain-like basic building units, characteristic of wolframite (NaWO₄). The 1D chains are stacked to create 2D layers; the cations Ag⁺ and Na⁺ lie between these layers. The vanadium oxide-fluoride octahedra are ordered by the use of cations (Ag⁺, Na⁺) that differ in polarizability. In the case of sodium-ion batteries, thermodynamically, the use of a sodium anode introduces a 300 mV loss in overall cell voltage as compared to a lithium anode; however, this can be counter-balanced by introduction of fluoride into the framework to raise the reduction potentials via an inductive effect. This allows sodium-ion batteries to have comparable voltages to lithium systems. With SSVOF as a baseline compound, we have identified new materials design rules for emerging sodium-ion systems that do not apply to lithium-ion systems. These strategies can be applied broadly to provide materials of interest for fundamental structural chemistry and appreciable voltages for sodium-ion electrochemistry

AgNa(VO₂F₂)₂: A Trioxovanadium Fluoride with Unconventional Electrochemical Properties

We present structural and electrochemical analyses of a new double-wolframite compound: AgNa­(VO₂F₂)₂ or SSVOF. SSVOF is fully ordered and displays electrochemical characteristics that give insight into electrode design for energy storage beyond lithium-ion chemistries. The compound contains trioxovanadium fluoride octahedra that combine to form one-dimensional chain-like basic building units, characteristic of wolframite (NaWO₄). The 1D chains are stacked to create 2D layers; the cations Ag⁺ and Na⁺ lie between these layers. The vanadium oxide-fluoride octahedra are ordered by the use of cations (Ag⁺, Na⁺) that differ in polarizability. In the case of sodium-ion batteries, thermodynamically, the use of a sodium anode introduces a 300 mV loss in overall cell voltage as compared to a lithium anode; however, this can be counter-balanced by introduction of fluoride into the framework to raise the reduction potentials via an inductive effect. This allows sodium-ion batteries to have comparable voltages to lithium systems. With SSVOF as a baseline compound, we have identified new materials design rules for emerging sodium-ion systems that do not apply to lithium-ion systems. These strategies can be applied broadly to provide materials of interest for fundamental structural chemistry and appreciable voltages for sodium-ion electrochemistry

A quantitative description of the binding equilibria of para-substituted aniline ligands and CdSe quantum dots

This paper describes the use of 1H NMR spectroscopy to measure the equilibrium constants for the solution-phase binding of two para-substituted aniline molecules (R-An), p-methoxyaniline (Me0-An) and p-bromoaniline (Br-An), to colloidal 4.1 nm CdSe quantum dots (QDs). Changes in the chemical shifts of the aromatic protons located ortho to the amine group on R-An were used to construct a binding isotherm for each R-An/QD system. These isotherms fit to a Langmuir function to yield Ka, the equilibrium constant for binding of the R-An ligands to the QDs; Ka almost equal to 150 M-1 and DeltaGads almost equal to -19 kJ/mol for both R = MeO and R = Br. 31P NMR indicates that the native octylphosphonate ligands, which, by inductively coupled plasma atomic emission spectroscopy, cover 90% of the QD surface, are not displaced upon binding of R-An. The MeO-An ligand quenches the photoluminescence of the QDs at much lower concentrations than does Br-An; the observation, therefore, that Ka,K-MeO-An almost equal to Ka,Br-An shows that this difference in quenching efficiencies is due solely to differences in the nature of the electronic interactions of the bound R-An with the excitonic state of the QD.</p