Eutectic quaternary

Following Table lists various. eutectic mixtures of explosives. See also BINARY, TERNARY AND QUATERNARY MIXTURES in Vol 2 of Encycl, pp B116 to Bl20... 

Ref 1), The term is generally applied to alloys melting below 450°F(233°C). They can be binary, ternary, quaternary, or quinary mixts of Bi, Pb, Sn, Cd, Indium and less frequently other metals. Eutectic alloys are relatively few in number and are the particular compns that have definite and minimum mp as compared with other mixts of the same metals. Table I of Ref 2 lists 17 eutectics of mp s ranging from 46.89° to 248.0°C. Of these the Lipowitz s eutectic, melting at 70.0° is well known. It consists of Bt 50, -Pb 27, Sn 13 Cd 10%. Table II of Ref 2 lists 13 non-eu ectic alloys with mp s ranging from 64.0 to 1J9°C. Table III of Ref 2 lists eight common fusible alloys of mp s 70 to 138°. Of... 

The effect of the quaternary ammonium cations is quite complex because the smaller cations depress the freezing point more because the halide salts of the smaller cations also have a higher freezing point the net result is that all of the eutectic mixtures will have reasonably similar freezing points. Hence the cation is observed to have little effect on the absolute freezing point of the eutectic-based ionic liquids. 

The conductivities of Type I ionic liquids based on anhydrous zinc and iron salts tend to be lower than those of the corresponding aluminum ionic liquids. This is due largely to the higher viscosity of the former, primarily because of the large size of the ions and the availability of suitably sized holes in the ionic liquids for the ions to move into. This has been quantified by the application of hole theory as is explained in Section 2.3.4. In general imidazolium-based liquids have lower viscosities and higher conductivities than the corresponding pyridinium or quaternary ammonium eutectics formed under the same conditions. 

It has recently been shown that the same principle can be applied to deep eutectic solvents by using small quaternary ammonium cations such as ethylammonium and fluorinated hydrogen bond donors such as trifluoroacetamide. However, there is only a limited benefit that can be achieved using this approach as the physical parameters cannot be varied totally independently of one another. For example there will be an optimum ion size too small and the lattice energy will increase the surface tension, too large and the ionic mobility will be impeded. 

Eutectics formed between quaternary ammonium salts and hydrogen bond donors (HBD) have potential windows that tend to be controlled by the stability of the carboxylic acid, amide or alcohol. In general the potential windows depend upon the pfCa of the HBD. Figure 4.13 shows the potential windows of eutectics formed between ChCl with ethylene glycol, urea and malonic acid. 

Abbott et al. [98-103] reported the synthesis and characterization of new moisture-stable, Lewis acidic ionic liquids made from metal chlorides and commercially available quaternary ammonium salts (see Chapter 2.3). They showed that mixtures of choline chloride (2-hydroxyethyltrimethylammonium chloride, [Me3NC2H40H]Cl and MCU (M=Zn, Sn) give conducting and viscous liquids at or around room temperature. These deep eutectic solvents/ionic liquids are easy to prepare, are water-and air-stable, and their low cost enables their use in large-scale applications. Furthermore, they reported [104] that a dark green, viscous liquid can be formed by mixing choline chloride with chromium(III) chloride hexahydrate and that the... 

Eutectic mixtures of quaternary ammonium salts with Lewis or Brpnsted acids were described as ILs [156], The conductivity, viscosity, density, and surface tension of a number of glycolic mixtures with choline chloride were measured over the mole fraction range 0-0.33. The data were fitted to hole theory. It was proposed that the composition at which the measured conductivity matched the theoretical value... 

The binary compound BCX3 divides the AX-BX-CX2 and DX2-BX-CX2 ternary systems into four simple ternary subsystems. The crystallization paths of ternary mixtures end in one of the six ternary eutectic points E , where the ternary mixtures solidify. The crystallization path of any quaternary mixture follows the dotted boundary lines inside the concentration tetrahedron and ends in one of the two quaternary eutectic points Eq,. 

Three quaternary eutectic points were found in the quaternary phase diagram KF-KCl-KBF4-K2TiF6. Their coordinates are ... 

The simplest approach to obtain ILs from natural sources is surely the direct use of quaternary ammonium salts. Choline chloride, a salt melting at 302 °C, has been transformed recently by Davies and co-workers in a fluid at room temperature by mixing the organic salt with metal chlorides or other simple organic compounds (such as, urea or polyalcohols), which depress the melting point producing liquids with significant ionic character (Scheme 2). These liquids systems are known as eutectic mixtures. 

Information on the phase relationships in the Ti-Zr-Si-Al system is very limited and is mostly contained in the papers [14,15], According to our results, at stable 5A1 or 5Zr, the system behaves similar to the ternary Ti-Zr-Si or Ti-Si-Al, respectively (Fig. 11). The isopleth at 5Si + 5A1 (Fig. 12) is similar to those of the ternary Ti-Zr-Si system, while the temperatures of the a+(3+S2 three-phase field in the quaternary system are about 100°C higher than in the ternary. Aluminum additions to ternary Ti-Zr-Si alloys result in significant strengthening of both the Ti-matrix and the (3+S2 eutectic when Zr concentration increases (Fig. 13). In the case of the eutectic alloy this is in contrast with ternary Al-free alloys. This explains some of the increase in the long-term hot hardness versus Zr... 

Taking into account that the volume content, size, distribution and properties of the reinforcing boride phase practically do not change with the alloying studied here, the strengthening of the ternary and quaternary eutectic alloys should be attributed practically in full to solid- solution strengthening of the titanium alloy matrix. 

The bend tests also show that the yield stress of the quaternary Ti-lOAl-X-(5 or 7.5)B (at.%) alloys is quite high, and that the hypo-eutectic alloys have a lower yield stress but their plasticity is much larger. 

Nitrates. Thermodynamic parameters (AH=114kJmor AS = 62 J moF K ) for reaction (16) in NaNOs-KNOa eutectic melt have been determined (500— 700 K). Corresponding data (AH = 95 kJ moF AS = 84 J moF K ) for reaction (17) have also been calculated. Physicochemical analyses have been carried out on NaNOa-KNOs, Ca(N0a)2-Sr(N03)2, Sr(NOa)2-Ba(NOa)2" binary systems (generally as part of a quaternary reciprocal system), and LiNOa-RbNOa-CsNOa and LiN0a-KN03-Sr(N0a)2 ternary systems. 

The quaternary B-C-Si-Ti system has not yet been established completely. Evidently TiB2 and SiC form a eutectic and can be cast after arc-melting [107], TiB2-Bi2(B, C, Si)3-SiC composites are chemically stable and may form a quasiternary eutectic. Composites of these three hard materials can be prepared either by direct hot pressing or by reactive infiltration of porous B4C bodies with an Si-TiSi2 eutectic melt [108, 109]. Of technical interest is the ternary boundary system C-Si-Ti studied by Brukl [110], Borisova et al. [Ill], and Holleck [112], calculated by Touanen et al. [113] and experimentally re-examined by Wakelkamp etal. [114],... 

The age of the modern glass fiber started in 1940 with a patent claiming new compositions and the production of continuous fibers [6] based on the dominating quaternary eutectic (60% Si02 - 9% AI2O3 - 27% CaO - 4% MgO). 

Na20. The second generic E-glass variant was disclosed in 1943. It was also a derivative of the quaternary eutectic [8] but specifically covered 9-11% B2O3 as an auxiliary flux. These adjustments reduced the liquidus temperature to 1120°C and the 1000 (log 3) poise forming temperature to 1200°C, thus offering a AT of SOX. 

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