Complex molecular ratio

One of the best oxidation-reduction indicators is the 1,10-phenanthroline-iron(II) complex. The base 1,10-phenanthroline combines readily in solution with iron(II) salts in the molecular ratio 3 base l iron(II) ion forming the intensely red l,10-phenanthroline-iron(II) complex ion with strong oxidising agents the iron(III) complex ion is formed, which has a pale blue colour. The colour change is a very striking one ... 

Reactions leading to surface-active diamides form emulsions of the hydrated [A1(H20)6]C13 complex. However, by hydrolysis of the RPOCl2-AlCl3 complex with water at a molecular ratio of 1 6-7.5 in methylene chloride at a temperature of -10°C, the A1C13 from the complex reacts selectively forming a precipitation of [A1(H20)6]C13, which can be easily filtered off. From the solvent the alkanephosphonic acid dichloride can be isolated in good quality (Table 4). 

Samples are hydrolyzed with hydrochloric acid and stannous chloride solution at elevated temperature, and the evolved carbon disulfide is drawn with an air steam through two gas washing tubes in series containing lead acetate and sodium hydroxide solutions and an absorption tube containing an ethanolic solution of cupric acetate and diethanolamine. Lead acetate and sodium hydroxide remove hydrogen sulfide and other impurities. In the absorption tube, the carbon disulfide forms two cupric complexes of Af,Af-bis(2-hydroxyethyl)dithiocarbamic acid with molecular ratios Cu CS2 of 1 1 and 1 2. These complexes are measured simultaneously by spectrophotometry at 453 nm. 

For XV) complexes have been obtained with molecular ratios 1 1 for potassium and sodium salts, 2 3 for rubidium and ammonium thiocyanate, and 1 2 for caesium thiocyanate. The rubidium and ammonium thiocyanate compounds are isomorphous, and the structure of the former was the first of this type to be determined 92). In the crystal there is a 1 1 complex and a molecule of crystallisation of un-complexed (XT). The metal is coordinated by six coplanar oxygen atoms... 

Similar products could be generated via azomethine yhdes derived by a formal 1,2-H shift from the precusor imine, rather than by the decarboxylative approach outlined above (82,83). For example (83), condensation of aldehyde 272 with the requisite amino ester 273 led to the intermediate ylide, which dehvered adducts 274 and 275 in a 1.2 1 ratio in 75% yield. Grigg has once again applied this protocol to the synthesis of a wide range of complex molecular frameworks (276... 

The divergent synthetic approach is schematically summarized in Figure 7. Reaction of the mononuclear complex-ligand tRu(2,3-dpp)j] with the complex-metal [Ru(2,3-Medpp)2Cl2] in a 1 3 molecular ratio leads to a tetranuclear complex (first dendrimer generation) which in its peiipheiy contains six protected chelating sites. Demethylation of this species restores its ligand ability and yields... 

For a same molecular ratio of aqueous NaY solutions (Y = OH, Cl), experimental data underlines specific effects of nascent OH radicals on transient UV and near-IR electronic configurations. Complex investigations of PHET reactions in the polarization CTTS well of aqueous CT and OH ions are in progress. We should wonder whether a change in the size of ionic radius (OH -1.76 A vs Cl" 2.35 A) or in the separation of the energy levels influence early branchings of ultrafast electronic trajectories. A key point of these studies is that the spectroscopic predictions of computed model-dependent analysis are compared to a direct identification of transient spectral bands, using a cooled Optical Multichannel Analyzer... 

The optimum condensation at molecular ratios of 3 to 1 and 1 to 3 in egg lecithin-cholesterol monolayers and 1 to 1 in dipalmitoyl lecithin-cholesterol monolayers (42) do not imply complex formation between lecithin and cholesterol but rather suggest average geometrical arrangements of these molecules. 

It has been shown that calcium chloride also markedly increases the solubility of lactose in methanol (Domovs and Freund 1960). From the highly concentrated viscous solutions formed there slowly crystallizes a complex of /3-lactose, calcium chloride, and methanol in a molecular ratio of 1 1 4. On addition of water to the concentrated solution, the complex previously described (a-lactose CaCli 7H20) soon crystallizes. 

A new complex of Ind and epirozole (molecular ratio equal to 2 1) has been prepared by the spherical crystallization technique and proven by means of IR spectroscopy and X-ray diffraction. " ... 

One of the characteristic features of octogen which distinguishes that compound from hexogen is that octogen readily fonns additional complexes — probably charge-transfer complexes. Tliey have been described by a number of authors [140, 136] but mainly by Selig [141]. Me described complexes of octogen in molecular ratio 1 1 with amines, for example... 

Aromatic diimides 71 and 72 derived from 9-epi-9-amino cinchona alkaloids and pyromellitic or 1,4,5,8-naphthalenetetracarboxylic anhydride have been designed by Gawronski and Kacprzak as novel chiral receptors. These triads are present at room temperature as equimolar mixture of syn and anti conformers, resulting from restricted rotation around the imide C—N bonds. These triads show high affinity toward carboxylic adds. The syn conformer binds preferentially 1,2-dicarboxylates in a 1 1 molecular ratio whereas the anti conformer is selective toward monocarbox-ylates forming a complex in a ratio 1 2 (triad acid). The response is sensitive and could be observed by either 1H NMR or by CD spectroscopy even when equimolar amounts of the adds are present in the solution. The competition experiments have shown a higher selectivity of triads toward 1,2-dicarboxylates [140],... 

These values have been calculated without considering hindrance of the attachment of additional enzyme molecules by the enzyme molecules already conjugated to the IgG molecule. For POase this influence will be significant at input ratios above 1-2, and can be calculated by rather complex mathematics (Archer, 1976). As an example the values obtained by these formulas for the fractions of antibodies with 0, 1,2, etc. bound POase moleeules are given between parentheses at the input molecular ratio of 2, where deviations become significant. 

In contrast to the low yield when hydrogen chloride is employed, an 88% yield of 2,4,6-triphenyl- 1,3,5-triazine (7) is obtained when chlorosulfonic acid is used as catalyst in a molecular ratio of 3 1 (CiSOjH/PhCN) at 0-5 C C and a reaction time of 12 to 24 hours.174 Trifluo-romethanesulfonic acid as a catalyst and solvent trimerizes benzonitrile at 91 °C in a yield of 66%.175 Lewis acids alone, such as aluminum, zinc, iron or titanium chlorides, phosphorus pentachloride, and boron trifluoride, have a considerably lower catalytic activity than the corresponding mixtures of Lewis acid with various promotors, such as mineral acids, organic acids and water. These differences are attributed to a change in the structure of the active complexes with the aryl cyanides. 

We have defined in-house calibrations of source roek maturity from various petroleum systems, assessed as source roek vitrinite reflectance equivalent as a proxy for maximum source rock temperature. The molecular parameter versus Ro% calibrations referred to below are either based on published source rock parameters we have validated to our satisfaction (e.g. Schaefer Littke 1988) or from in-house work on source rock maturity sequences. Inevitably, as all oils are mixtures we cannot accurately define point maturities for reservoired oils but by judicious choice of calibrant source-rock samples we feel the calibrations referred to are as robust as is possible in dealing with spatially and temporally complex entities such as source basins. The oil maturities we report are those interpreted classically based on correlations between measured oil molecular ratios and the... 

Figures 3 illustrate molecular ratios observed in the organic solution. These results suggest that there may be two different chemical structures for the organic solutions. In this chapter, we describe the TBP complex with nitric acid, TBP(HN03)x(H20)yas TBP-HNO3-H2O. Similarly, TBP-HNO3-H2O-CO2 denotes a high pressure mixture of TBP-HNO3-H2O and SF-CO2.

Figure 3. Molecular ratio of(a)HNOj to TBP(left) and (b)HNOs to H2O (right) in the TBP complex with nitric acid as a function of molecular ratio of nitric acid to water in equilibrated aqueous nitric acid.

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