Tungsten cells

Sample cells were fabricated from tungsten. Additional crucibles composed of a Pt-40 w/o Rh-8 w/o W alloy were also used in experiments on the PuPt phase. Each tungsten cell was vacuum outgassed at 1800 for 1 h before an experiment. The cell temperature was determined during the measurements by sighting with a pyrometer (Pyrometer Instrument Co.) onto a blackbody hole in each cell base. The pyrometer and sight glasses were calibrated with an NBS standard lamp. 

A mass-spectrometric study of the vaporisation from Th02(cr) from tungsten cells at temperatures from ca. 2500 to 2825 K showed that the vapour in fact contains similar amounts of ThO(g) and Th02(g). 

The BCC structure is illustrated in figure Al.3,3. Elements such as sodium, tungsten and iron fonn in the BCC structure. The conventional unit cell of the BCC structure is cubic, like FCC, with the length of the edge given by the lattice parameter, a. There are two atoms in the conventional cell. In the primitive unit cell, there is only one atom and the lattice vectors are given by... 

Fused Salt Electrolysis. Only light RE metals (La to Nd) can be produced by molten salt electrolysis because these have a relatively low melting point compared to those of medium and heavy RE metals. Deposition of an alloy with another metal, Zn for example, is an alternative. The feed is a mixture of anhydrous RE chlorides and fluorides. The materials from which the electrolysis cell is constmcted are of great importance because of the high reactivity of the rare-earth metals. Molybdenum, tungsten, tantalum, or alternatively iron with ceramic or graphite linings are used as cmcible materials. Carbon is frequently used as an anode material. 

In many cases, the deposited material can retain some of the original chemical constituents, such as hydrogen in siUcon from the deposition from silane, or chlorine in tungsten from the deposition from WCl. This can be beneficial or detrimental. For example, the retention of hydrogen in siUcon allows the deposition of amorphous siUcon, a-Si H, which is used in solar cells, but the retention of chlorine in tungsten is detrimental to subsequent fusion welding of the tungsten. 

Cesium was first produced ia the metallic state by electrolysis of a molten mixture of cesium and barium cyanides (2). Subsequentiy the more common thermochemical—reduction techniques were developed (3,4). There were essentially no iadustrial uses for cesium until 1926, when it was used for a few years as a getter and as an effective agent ia reduciag the electron work function on coated tungsten filaments ia radio tubes. Development of photoelectric cells a few years later resulted ia a small but steady consumption of cesium and other appHcations for cesium ia photosensing elements followed. 

When 0.4 < x < 0.53, an orthorhombic phase is observed in the AgxNb02+xFi.x system. This phase undergoes a phase transition at 900°C that leads to the formation of a tetragonal phase, which crystallizes in a tetragonal tungsten bronze-type structure with cell parameters a = 12.343 and c = 3.905 A. When 0.82 < x < 1, solid solutions based on AgNb03 were found, which crystallize in a perovskite-type structure. 

In these instruments the monochromated beam of radiation, from tungsten and deuterium lamp sources, is divided into two identical beams, one of which passes through the reference cell and the other through the sample cell. The signal for the absorption of the contents of the reference cell is automatically subtracted from that from the sample cell giving a net signal corresponding to the absorption for the components in the sample solution. 

Further, tungsten oxysulfide films, WOyS, have shown promising behavior as positive electrodes in microbatteries, unlike WS2 that is not suitable as cathode in lithium cells. Using amorphous thin films of WO1.05S2 and WO1.35S2.2 in the cell Li/LiAsFe, 1 M ethyl-methyl sulfone (EMS)/W03,Sz, Martin-Litas et al. [80] obtained current densities up to 37 xA cm between 1.6 and 3 V. In these cathode materials, 0.6 and 0.8 lithium per formula unit, respectively, could be intercalated and de-intercalated reversibly. 

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