Gallium, liquid

Focused ion beams (FlBs) have become a popular tool for surface modification of materials and functional structure prototyping at the micro- and nanoscale. Modem FlBs have spot sizes of <5 nm and are produced by using electrostatic lenses to focus the image of a point source, often gallium liquid metal ion source, onto the substrate and to deflect it in a precise fashion. For a comprehensive review of recent... 

The idea of solvent-dependent interactions represents a general and fascinating topic of research. Imagine the interaction of solutes in mercury, in liquid gallium, liquid sodium, in a highly polarizable organic solvent, etc. Due to the peculiarities of these solvents, we will have different chemistry going on in them. 

The spectra were acquired using a Physical Electronics PHI 7200 ToF-SIMS instrument (Physical Electronics, Eden Prairie, MN, USA), allowing parallel mass registration with high sensitivity and high mass resolution. A gallium liquid-metal ion (LMI) gun at 25 keV beam energy was used for spatially resolved ToF-SIMS analysis. The beam diameter was 0.25 p-m, the pulse width 100 ns and the TDC bin size 10 ns. A mass resolution m tsm) of 4500 at m/z = 29 was obtained. 

In Fig. III-7 we show a molecular dynamics computation for the density profile and pressure difference P - p across the interface of an argonlike system [66] (see also Refs. 67, 68 and citations therein). Similar calculations have been made of 5 in Eq. III-20 [69, 70]. Monte Carlo calculations of the density profile of the vapor-liquid interface of magnesium how stratification penetrating about three atomic diameters into the liquid [71]. Experimental measurement of the transverse structure of the vapor-liquid interface of mercury and gallium showed structures that were indistinguishable from that of the bulk fluids [72, 73]. 

The actual structure at a vapor-liquid interface can be probed with x-rays. Rice and co-workers [72,73,117] use x-ray reflection to determine the composition perpendicular to the surface and grazing incidence x-ray diffraction to study the transverse structure of an interface. In a study of bismuth gallium mixtures. 

Cesium, gallium, and mercury are the only three metals that are liquid at room temperature. Cesium reacts explosively with cold water, and reacts with ice at temperatures above -116C. Cesium hydroxide, the strongest base known, attacks glass. 

Liquid Metals. If operating temperatures rise above 250—300°C, where many organic fluids decompose and water exerts high vapor pressure, hquid metals have found some use, eg, mercury for limited appHcation in turbines sodium, especially its low melting eutectic with 23 wt % potassium, as a hydrauhc fluid and coolant in nuclear reactors and potassium, mbidium, cesium, and gallium in some special uses. 

Another type of ion gun produces positive ions from a liquid metal (almost always gallium) in the manner shown schematically in Fig. 3.2 [3.7]. A fine needle (f tip radius 5 pm) of refractory metal passes through a capillary tube (d) into a reservoir of liquid metal (e). The liquid is drawn up through the tube over the needle tip by capil-... 

The equilibrium levels of the reaction products are very small, but both can dissolve in liquid sodium, and sodium oxide can form compounds with silica. As a consequence, the reaction moves to the right, leading to further reduction of silica. Nevertheless, vitreous silica crucibles have been used sucessfully for containing molten antimony (850°C), copper (1 210°C), gallium (1 100°C), germanium (1 100°C), lead (500°C) and tin (900 C). 

Arsenic and antimony are metalloids. They have been known in the pure state since ancient times because they are easily obtained from their ores (Fig. 15.3). In the elemental state, they are used primarily in the semiconductor industry and in the lead alloys used as electrodes in storage batteries. Gallium arsenide is used in lasers, including the lasers used in CD players. Metallic bismuth, with its large, weakly bonded atoms, has a low melting point and is used in alloys that serve as fire detectors in sprinkler systems the alloy melts when a fire breaks out nearby, and the sprinkler system is activated. Like ice, solid bismuth is less dense than the liquid. As a result, molten bismuth does not shrink when it solidifies in molds, and so it is used to make low-temperature castings. 

The volatile metal is separated by distillation and condensed. Mercury is the only metallic element that is liquid at room temperature (gallium and cesium are liquids on warm days). It has a long liquid range, from its melting point of — 39°C to its boiling point of 357°C, and so it is well suited for its use in thermometers, silent electrical switches, and high-vacuum pumps. 

Obviously this method is limited to liquid metals like mercury and gallium and their amalgams respectively alloys. Modifications of this method have been reported [86FIor]. At elevated temperatures with molten salt electrolytes alloys with an appropriately low melting point can be investigated, too. 

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