Solutions ratio

Solvent Mixing ratio Solution viscosity - 20°C (mPa s) Tack time (min)... 

Although the 5 1 volume ratio solutions can be used for coating applications, the gellike material that results on solvent removal limits the copolymer s utility. Fortunately, the reactive Si—H bonds that remain in the copolymer can be used to further modify polymer properties. The presence of the catalyst in the final reaction solution provides a simple means of further modifying the original copolymer. Thus, after 72 h of reaction,... 

Besides organic growth modifiers. Mg and Sr play a primary role the incorporation of Mg + has been shown to modily the morphology, solubility, and polymorphic expression of CaCOs biominerals. Furthermore, Mg is the principal inhibitor of calcite growth in natural waters. However, the ftmdamental mechanistic interactions of Mg with the calcite surface remain controversial. In vitro experiments show that Mg contents of ACC depend on the Mg/Ca ratio solution, and that Mg stabilizes ACC. ... 

Cobalt hydrotalcites were obtained by co-precipitation and ageing of slurries indicated in Table II, using a technique similar to that of Reichle ( ), viz, reaction of Na0H/Na2C03 (3/1 ratio) solution (3.5 M in OH ) with a mixed Co/Al nitrate solution (1.5 M in Co " ), such that the number of equivalents of base added equalled the number of equivalents of Co+Al ions in solution. For ageing the slurry at 200 C, an autoclave was used. The degree of crystallinity was estimated from the width of d(oo3) XRD. 

When a 1 10 mole ratio solution of COS in propylene was irradiated in the solid phase at liquid nitrogen temperature, in addition to a minor unidentified product, the three principal gas phase products, MVM, AM, and PS, were formed in a relative yield of 0.10 0 0.34 1.00, respectively. The corresponding gas phase values were 0 21 0.25 1.00. 

Calcium bromide, currently quantitywise the most important inorganic bromide, is utilized in crude oil extraction as a so-called packing fluid or drilling fluid . Packing fluids surround the archimedian screw and equalize the pressure. Depending upon the pressure ratio solutions of sodium ehloride, of mixtures of sodium chloride with sodium carbonate or calcium chloride, of calcium chloride, of mixtures of ealcium chloride and calcium bromide or of mixtures of caleium bromide and zinc bromide (see below) are utilized. Solutions with 53% by weight of calcium bromides are used, which have a density of ca. 1.7 g/mL. 

X = mass ratio solute to feed solvent in raffinate leaving process Yj = mass ratio solute to extraction solvent in extraction solvent entering process E = extraction factor... 

Free amino acids were analyzed by first dissolving san5>les (0.05-0.1 g/mL) in 0.2 N citrate buffer, pH 2.2, and the mixture shaken for 15 min at room tenq)erature. Mixture was centrifuged at 7000 x g for 5 minutes and supernatant deproteinized with 3.5 % sulfosalicylic acid solution by mixing at a 1 1 ratio. Solution was chilled and shaken to maximize precipitation of imwanted protein. After thawing, the solution was centrifuged at 7000 x g for 5 minutes. 

A procss has been developed to gainfully utilize the spent Fe203-Cr203 based CO-Conversion catalyst to conserve raw materials and reduce air soil pollution. It involved dissolution of the mass in aqueous H2SO4 followed by partial reduction of the Fe(III) in solution by Fe(0) to Fe(II) so as to attain specific Fe(IIl) /Fe(II) ratio. Solutions having this ratio in the range 0.7 to 1.7 were found to result, on treatment with NaOH solution, in masses which have ideal CO-Conversion catalytic qualities. 

Figure 1. Sodium silicate production since 1900 as 40° Be 3.3 ratio solution (data smoothed to show trends). CGR since 1925 is 2.6%.

Figures la and Ic show the structure of the phase-separated polymer blend films obtained by dip coating from a PS-COOH/PMMA (30 70 weight ratio) solution. The morphology of the as-deposited films of two different (15 and 30 nm) thicknesses agreed well with their PS content of 30%. Indeed, the minor PS phase was dispersed in the major PMMA phase. However, after the anneahng and extraction of PMMA, the grafted PS layer demonstrated a rather different type of surface structures for the PS-COOH /PMMA films of different...

Even though the oils have a low gas-to-oil ratio, solution gas drive appears to be major factor (97, 100). Gas that comes out of solution is slow to coalesce because of the viscosity of the oil, and a foamy oil flow results. The nature of the foamy oil has been discussed (101), and it has been postulated that it is one of several factors contributing to the production of solids from these types of reservoirs. 

However, the previously mentioned hydrolytic reaction is very sensitive to experimental conditions, such as the presence of acid or base catalysts, reaction temperature, and molar ratio of alkoxides to H2O. Three critical experimental parameters (pH, temperature, and reaction time) that affected the rate of hydrolysis were systematically studied by Paulick et al. (34). The volume ratio of 100 ml mixed alkoxide [Al(OC3H7)3 and tetraethylorthosilicate (TEOS)] solution to 500 ml of an H2O/CH3OH (3 1 ratio) solution was used for all the experiments. It was found that in an acid environment (pH 2) the hydrolytic decomposition was completed within 7 h at room temperature. Stoichiometric mullite was the only product obtained, as evidenced by both elemental analysis and x-ray diffraction. Under alkaline conditions (pH 10), the degree of hydrolytic decomposition was both time and temperature dependent. The TEOS was only partially hydrolyzed even after heating at 70°C for 20 h. The oxide powder obtained was composed of 65% AI2O3 and 35% mullite. The degree of hydrolysis is only moderately affected by temperature, and it is not affected by the reaction time. 

The water used in making all solutions was prepared using 10 MOhm water. Stock solutions of sodium silicates were made from carefully assayed commercially available solutions for ratio (w/w) values of 2.0 and 3.8 and from sodium metasilicate and NaOH for the 0.5 ratio solution. 

The results for Cu " are represented graphically in Figure 3 in the same manner as for Ca and Mg and we see again a statistically different interaction of Cu with the species present in higher ratio silicate solution when compared to the lower ratio solution and hydroxide. Also, of interest, is the fact that the values of Cu " activity are somewhat higher in all cases than the values one would predict from the equilibrium ... 

This observation from results using silica sols is consistent with the experimental results observed here for the higher ratio solutions. Thus, it is most probable that the same mechanisms associated with surface complex formation with deprotonated silica, are operating here. 

It would appear that the most probable explanation of the results is that in higher ratio solutions the presence of colloidal size silicate anions with more acidic surface silanol groups readily adsorb nucleating metal ion hydroxides thus enhancing the reduction of pMe. This adsorption might be enhanced by the presence of 0H , or increased5Si-0 sites on the colloidal sized silica surfaces at higher pH values. 

Fto. 14. Rcstricled-difliision paiuneier ff veisus the ratio /. —(solute Stokes diemelci)/(pefticlepoie diameter) firom Christ et at (72). ( ) SECdele ofGliristet at (7 (0) native proteins, 15 nm-pore column ( ) denatured proteins, 30-nin-poce column, (b) Re-versed-phase HPLCdatt of Stadalius era/. (27) (O) data for IS-nm-pote column ( ) data for 30-nm-poie column (--------------) same curve in (a) a (b) (—) Eq. (63). 

Weight ratio solute in diluent leaving stage j, kg A /kg D Y. Weight ratio solute in solvent leaving stage j. kg A /kg S... 

To a l l-mol ratio solution of indole and enone in EtOH is added NaAuCl4-2 H2O (5 mol%). The resulting mixture is allowed to react with stirring at RT or at 30 °C while being monitored by TLC or GC-mass spectroscopy (MS). After completion, the solvent is removed by evaporation under reduced pressure. To the residue, acetone (few mL) is added to precipitate the catalyst, which is separated by filtration. The filtrate is concentrated and the crude products are purified by chromatography on silica gel (230-400 mesh) eluting with -hexane/EtOAc mixtures. ... 

Draw Resonance appears as a continuous variation in bubble diameter. As in other extrusion processes, such as profile, it occurs when the melt is stretched too quickly (i.e., a high take-up ratio). Solutions act to reduce the take-up ratio, for example increasing the melt (screw) speed. 

Picomole (10 mol) Polyaromatic hydrocarbon Refractive index Reversed phase Sodium dodecyl sulfate Signal-to-noise ratio Solute retention time Void volume of system Triethylamine Trifluoroacetic acid Tetrahydrofuran Ultraviolet... 

In similar studies, Borisov and Ryzhenko (40) observed the absorption and reflection spectra (500-1700 cm" ) to vary with the SiOj Na20 ratio. In concentrated 1.5 ratio solution of (HO)2Si02, and (HO) (SiO)40 the cyclic tetramer ion predominated, but disappeared when more alkali was added or when the solution was diluted-. No dimer or trimer was mentioned. 

Similarly, Her (64) found that a 3.3 l.O ratio solution of sodium silicate containing 12% SiOj could be added to the acid resin slurry to obtain silicic acid with a number-average molecular weight of 200, as Si02. A more dilute solution containing 2% silica gave product with molecular weight of 180 (63). This value compares with 325 found by Nauman and Debye (37) in a more dilute solution of sodium silicate where the lower pH permits some further polymerization of the polysilicate ions. 

However. (CHj)4N- - silicate solutions differ from the sodium silicate solutions in that even at 1.0 ratio, colloid still persists along with HSiOj". Likewise, in 3.3 ratio solutions, there is much more colloid in the (CH3)4N based solutions than with sodium base. The authors conclude that TMA cation shifts the equilibrium to a mixture of low and high species. It is likely that the colloid phase is stabilized by an adsorbed monolayer of (CH3)4N . 

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