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Established Salts

A number of lithium salts are well established as salts which are used or have been previously used for hthium battery electrolytes, although many of these do not meet the necessary criterion for commercial battery electrolytes. Frequently studied lithium salts include (Fig. 1.3) [12,40] the following  [Pg.7]

Lithium hexafluorophosphate is used almost exclusively in commercial Li-ion batteries. This salt has thus far demonstrated the best balance of essential properties necessary for a primary Li-ion electrolyte salt [12, 40], In aprotic solvents, the resulting electrolytes have some of the highest conductivity values measured. LiPEg-based electrolytes react to form a stable interface with the A1 [Pg.7]

LiSOjCFs. Lithium trifluoromethanesulfonate (triflate— most commonly abbreviated as CF3SO3 in the scientific literature) was at one time widely used for electrolytes, especially for polymer electrolytes [97-107], This salt has a high thermal stability [56] and is not susceptible to hydrolysis due to the stability of the C-F bond. Electrolytes with this salt, however, are found to be notably less conductive than those with LiPFg [5,108-110], and LiSOsCFj-based electrolytes corrode the A1 current collector at high potential [59, 65-67], Thns, while this salt has been extensively nsed for research purposes, it is not used in commercial Li-ion batteries. [Pg.8]


The initial product, nitrosobenzene, is so easily reduced to p-phenylhydroxyl-amine that it has never been isolated in the free state, but its presence has been established by reaction in solution with hydroxylamine to 3deld a phenyldi-azonium salt, which couples readily with a a-naphthylamine to form the dyestuff phenyl-azo-a-naphthylamine (compare Section IV,77) ... [Pg.628]

Naturally occurring krypton contains six stable isotopes. Seventeen other unstable isotopes are now recognized. The spectral lines of krypton are easily produced and some are very sharp. While krypton is generally thought of as a rare gas that normally does not combine with other elements to form compounds, it now appears that the existence of some krypton compounds is established. Krypton difluoride has been prepared in gram quantities and can be made by several methods. A higher fluoride of krypton and a salt of an oxyacid of krypton also have been... [Pg.100]

For this series of compounds qualitative information is quite extensive. Application of the criteria discussed in 8.2, in particular comparison with the corresponding methyl quaternary salt, establishment of the rate profile for nitration in sulphuric acid, and consideration of the encounter rate and activation parameters, shows that 2,4,6-collidine is nitrated as its cation. The same is true for the 3-nitration of 2,4- ... [Pg.190]

Many monomeric heterocyclic anhydrobases can be isolated now using specific methods (44), but application of these methods to thiazole ring did not succeed however, appropriate conditions lead to the separation of a dimer, the structure of which has been established by its NMR Spectra and chemical reactivity (26). The most probable mechanism of its formation appears identical with the one previously described in the benzothiazolium series (24). A second molecule of quaternary salt A3... [Pg.37]

At first, the dimeric nature of the base isolated from 3-ethyl-2-methyl-4-phenylthiazolium was postulated via a chemical route. Indeed the adduct of ICH, on a similar 2-ethylidene base is a 2-isopropylthiazolium salt in the case of methylene base it is an anilinovinyl compound identified by its absorption spectrum and chemical reactivity (45-47). This dimeric structure of the molecule has been definitively established by its NMR spectrum. It is very similar to the base issued from 2.3-dimethyl-benzo thiazolium (48). It corresponds to 2-(3 -ethyl-4 -phenyl-2 -methylenethiazolinilydene)2-methyl-3-ethyl-4-phenylthiazoline (13). There is only one methyl signal (62 = 2.59), and two series of signals (63= 1.36-3.90, 63= 1.12-3.78) correspond to ethyl groups. Three protons attributed to positions T,5,5 are shifted to a lower field 5.93, 6.58, and 8.36 ppm. The bulk of the ten phenyl protons is at 7.3 ppm (Scheme 22). [Pg.39]

By protodetritiation of the thiazolium salt (152) and of 2 tritiothiamine (153) Kemp and O Brien (432) measured a kinetic isotope effect, of 2.7 for (152). They evaluated the rate of protonation of the corresponding yiides and found that the enzyme-mediated reaction of thiamine with pyruvate is at least 10 times faster than the maximum rate possible with 152. The scale of this rate ratio establishes the presence within the enzyme of a higher concentration of thiamine ylide than can be realized in water. Thus a major role of the enzyme might be to change the relative thermodynamic stabilities of thiamine and its ylide (432). [Pg.118]

Standard Hydrogen Electrode The standard hydrogen electrode (SHE) is rarely used for routine analytical work, but is important because it is the reference electrode used to establish standard-state potentials for other half-reactions. The SHE consists of a Pt electrode immersed in a solution in which the hydrogen ion activity is 1.00 and in which H2 gas is bubbled at a pressure of 1 atm (Figure 11.7). A conventional salt bridge connects the SHE to the indicator half-cell. The shorthand notation for the standard hydrogen electrode is... [Pg.471]

We consider this system in an osmotic pressure experiment based on a membrane which is permeable to all components except the polymeric ion P that is, solvent molecules, M" , and X can pass through the membrane freely to establish the osmotic equilibrium, and only the polymer is restrained. It does not matter whether pure solvent or a salt solution is introduced across the membrane from the polymer solution or whether the latter initially contains salt or not. At equilibrium both sides of the osmometer contain solvent, M , and X in such proportions as to satisfy the constaints imposed by electroneutrality and equilibrium conditions. [Pg.569]

Nearly half of the U.S. domestic food consumption of peanuts in 1993 was as peanut butter salted peanuts, at 27.3%, and peanut candy, at 23.9% made up the other half (137). Although the per capita domestic peanut consumption in the United States has increased steadily, the consumption in recent years has not kept pace with production. Domestic food use of peanuts has been confined almost entirely to roasted peanuts. A number of investigations and developmental efforts are being made to extend the use of nonroasted peanut products such as flour and meal flakes. As of the mid-1990s, market outlets for these latter products are neither sizable nor firmly established. The food-use patterns emphasize the uniqueness and demand for products having a distinct roasted-peanut flavor. The development of the desired flavor as well as the storage stability of such flavor in peanut-food products are therefore important. [Pg.278]

V. M. G. Mannar and H. L. Bradley, Guidelines for the Establishment on Solar Salt Facilities from Seawater, Underground Brines and Salted Takes, United Nations Industrial Development Organi2ation, 1983. [Pg.187]

The first three classes are called available chlorine compounds and are related to chlorine by the equilibria in equations 1—4. These equilibria are rapidly established in aqueous solution (6), but the dissolution of some hypochlorite salts and A/-chloro compounds can be quite slow. [Pg.141]

Owing to their particular interest two individual reactions will now be discussed separately. The reaction of methoxycarbonylhydrazine and 3-bromo-2,4-pentanedione affords, in addition to the expected pyrazole (608), a pyrazolium salt (609), the structure of which was established by X-ray crystallography (74TL1987). Aryldiazonium salts have been used instead of arylhydrazines in the synthesis of pyrazolines (610) and pyrazoles (611) (82JOC81). These compounds are formed by free radical decomposition of diazonium salts by titanium(n) chloride in the presence of a,/3-ethylenic ketones. [Pg.278]

The formation of transient benzazetidinones (251) in the photolysis and thermolysis of benzotriazin-4-ones (250) is well established (76AHC215) and the highly hindered adamantyl derivative has actually been isolated from flash pyrolysis of 4-adamantylbenzotriazinone (73JCS(Pl)868). A second route to such hindered benzazetidinones involves cyclization of the iminoketene valence tautomer (252 R = Bu ), the latter being generated by deprotonation of the anthranilium salts (253) (71JA1543). [Pg.278]

Determination of Na " and Na" ions in raw cosmetic materials was conducted with the developed method of flame photometry. A necessity of development of method of samples preparation arose up in the work process, as this spicily-aromatic raw material contained pectin in amount 0.1-0.5% and that prevented preparation of samples by standard method of extracts dilution and required incineration of analyzed sample, time of analysis was increased in 60 times. It was established that CaCl, solution with the concentration 0,4 % caused destmctions of the carbopol gel. It was established that the addition of 0,1% CaCl, and 0,1% NaCl salts solutions into the system intensified the effect of negative action of these salts onto the gel stmcture and the gel destmcted completely. [Pg.375]

The primary constituents to be measured are the pH of precipitation, sulfates, nitrates, ammonia, chloride ions, metal ions, phosphates, and specific conductivity. The pH measurements help to establish reliable longterm trends in patterns of acidic precipitation. The sulfate and nitrate information is related to anthropogenic sources where possible. The measurements of chloride ions, metal ions, and phosphates are related to sea spray and wind-blown dust sources. Specific conductivity is related to the level of dissolved salts in precipitation. [Pg.213]

Two other features of the reaction that have been established are the following (1) When DCl is used instead of HCl, unreacted olefin recovered by stopping the reaction at 50% completion contains no deuterium (2) added chloride salts (R4N+Cr) decrease the reaction rate, but other salts (R4N C104 ) do not. Write a mechanism for this reaction that is in accord with the data given. [Pg.403]

Comparison of these results indicates identity of the two substances isolated independently by Orekhov and Ehrenstein, but Spiith and Kesztler have suggested that Pictet s nicoteine and Ehrenstein s base, consisted of impure Z-anatabine (p. 46). In this connection it may be noted that Ehrenstein s base was laevorotatory in acid solution, whereas Salts of anabasine are dextrorotatory. These authors have themselves isolated Z-anabasine from tobacco. The identity of synthetic 2-(3 -Pyridyl)piperidine with dZ-anabasine seems to have been definitely established. Anabasis aphylla is the source of the anabasine raanufac-... [Pg.43]


See other pages where Established Salts is mentioned: [Pg.96]    [Pg.252]    [Pg.14]    [Pg.7]    [Pg.26]    [Pg.491]    [Pg.96]    [Pg.252]    [Pg.14]    [Pg.7]    [Pg.26]    [Pg.491]    [Pg.94]    [Pg.270]    [Pg.15]    [Pg.71]    [Pg.115]    [Pg.64]    [Pg.267]    [Pg.75]    [Pg.255]    [Pg.427]    [Pg.15]    [Pg.361]    [Pg.61]    [Pg.81]    [Pg.439]    [Pg.603]    [Pg.96]    [Pg.326]    [Pg.39]    [Pg.374]    [Pg.71]    [Pg.322]    [Pg.425]    [Pg.820]    [Pg.28]    [Pg.28]   


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Establishing

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