Washing, see Detergency


Dieterici s equation A modification of van der Waals equation, in which account is taken of the pressure gradient at the boundary of the gas. It is written  [c.136]

Dietrich, Lehn and Sauvage recognized not only the possibility of enclosing a cation completely in a lipophilic shell, but they also recognized the potential for using such systems for activating associated anions. This is made particularly clear in a paper which appeared some years later One of the original motivations for our work on cryptates rested on their potential use for salt solubilization, anion activation and phase transfer catalysis . This particular application is discussed below in Sect. 8.3.  [c.348]

Toluene is marketed mosdy as nitration and industrial grades. The generally accepted quality standards for the grades are given by ASTM D841 and D362, respectively, which are summarized in Tables 16 and 17, with the appropriate ASTM test method specified for determining the specification properties (40). Although the actual concentration of toluene in samples is not stipulated by these specifications, the purity is in fact controlled by the specific gravity and the boiling-range requirements of the method.  [c.187]

By far the most important metal containing dyes are derived from OjO-dUiydroxyazo stmctures in which one of the two azo nitrogen atoms and the two hydroxyl oxygen atoms are involved in bonding with the metal ion. Thus these dyes serve as terdentate ligands. In the case of metal ions with a coordination number of four, eg, Cu(H), the fourth position is usuaUy occupied by a solvent molecule (47).  [c.436]

In 1969, Dietrich, Lehn and Sauvage published the first report of a type of molecule which was to engender tremendous interest in the chemical community. These compounds were macrobicyclic polyethers having nitrogen pivot atoms and exhibiting the ability to bind a variety of metal cations. The syntheses of the first examples of macrobicyclic amines were carried out as illustrated in Eq. (8.1). The appropriate diaminopolyether and polyether diacyl chloride were condensed under high dilution conditions to give diamide 1 in 80% yield. Reduction was then effected using LiAlH4 to tetrahydrofuran to yield diamine 2 in 75% yield. A second equivalent of the diacyl chloride used in the first step was allowed to react with 2 (again, high dilution) affording the macrobicyclic diamide 3 in 45% yield. Reduction using diborane afforded the compound called [2.2.2]-cryptand (4) as its bis-borane adduct. Removal of the borane residues could be effected by treatment with 6 N HCl affording 4 in more than 90% yield from 3. The overall yield for the process was about 25%.  [c.347]

The actual catalyst is a complex formed from osmium tetroxide and a chiral ligand, e.g. dihydroquinine (DHQ) 9, dihydroquinidine (DHQD), Zj -dihydroqui-nine-phthalazine 10 or the respective dihydroquinidine derivative. The expensive and toxic osmium tetroxide is employed in small amounts only, together with a less expensive co-oxidant, e.g. potassium hexacyanoferrate(lll), which is used in stoichiometric quantities. The chiral ligand is also required in small amounts only. For the bench chemist, the procedure for the asymmetric fihydroxylation has been simplified with commercially available mixtures of reagents, e.g. AD-mix-a or AD-mix-/3, ° containing the appropriate cinchona alkaloid derivative  [c.257]


See pages that mention the term Washing, see Detergency : [c.259]    [c.414]    [c.177]    [c.204]    [c.267]    [c.706]    [c.206]   
Physical chemistry of surfaces (0) -- [ c.0 ]