Synthesis clear solution

Using the known gel compositions for the synthesis of ZSM-5 zeolites, recently, a method called clear solution synthesis has been proposed for the successful preparation of small sized ZSM-5 zeohtes [30]. Since the dear solution approach generally uses silica sp>ecies in molecular form and thus a transparent solution appears at the initial stage of crystallization, such synthesis system is also called homogeneous crystallization system [28,29]. Although the crystal size could be fadlely controlled by this method, such approach has obvious drawbacks such as low product yield (less than 5 wt. %), use of large amount of both SDAs... 

SINs. Two SIN compositions were studied, one having 10% oil prepolymer and the other 20% oil prepolymer, both dissolved in the styrene-DVB monomer solution. During the synthesis several morphological changes occurred in the mixture. Early in the reaction all components formed a mutual clear solution which was slightly yellow due to the original color of the prepolymer. As the free radical polymerization of styrene began, the polystyrene first produced remained soluble. At a critical concentration, phase separation... 

Coprecipitation Synthesis with Template (Method-D) In the preparation of sample lOD, Ni(N03)2 8H2O, ZrOCl2 8H2O, and YCl3(2) were dissolved in distilled water to get a clear solution. CTABr template was then added and the resulting solution was stirred for 30 min. Then, ammonia (70% 10 mL diluted to 105 mL with distilled water) was added to get a white gelatinous precipitate. The pH was maintained at around 9. The contents were stirred for 1 h and the precipitate was aged for 16.5 h, then filtered and calcined at 773 K for 1 h in a static air oven. 

The surfactant, cetyltrimethylammonium bromide, was dissolved in water to obtain a clear solution, in which the first swelling agent (decane) was then added drop by drop with stirring. After ten minutes stirring at room temperature, the second swelling agent (TMB) was introduced. Sodium silicate was added to the obtained micellar solution and the pH value was adjusted with sulfuric acid. The pH value and surfactant/silicium molar ratio was fixed at 10 and 0.62 according to the protocol established previously for conventional MCM-41 synthesis... 

SYNTHESIS To a clear solution of 40.4 g flake KOH in 400 mL warm EtOH there... 

SYNTHESIS To a solution of 100 g phloroglucinol dihydrate in 320 mL MeOH there was added 55 mL of concentrated H2S04, and the clear solution held under reflux conditions overnight. After cooling, there was added 500 mL H20, and the bulk of the MeOH was removed under vacuum. The residual oil was extracted with Et20, and the removal of this left 60 g of a red oil as residue. This was dissolved in... 

SYNTHESIS (from protocateehualdehyde) A solution of 18 g commercial protocatechualdehyde (3,4-dihydroxybenzaldehyde) in 200 mL warm acetic acid was filtered free of any insolubles, to provide a very dark but clear solution. With good stirring there was then added 20 g elemental bromine. The reaction spontaneously heated to about 30 °C and solids appeared in about 5 min. Stirring was continued for 1 h, and then the light gray solids that had formed were removed by filtration and lightly washed with acetic acid. 

When all the magnesium has been added and a clear solution obtained, the organic compound to be used in the synthesis (ketone, ester, etc.) is added gradually, and the mixture cooled in ice to modify the reaction if necessary. 

SYNTHESIS To a solution of 3.0 g 5-methoxytryptamine (see under melatonin for its preparation) in 20 mL sulfolane (tetramethylenesulfone) there was added 8.2 g diisopropylethyl amine and 10.7 g 2-iodopropane, and the two-phase mixture was heated on the steam bath with frequent shaking. After 3 h, the mixture was brought back to room temperature and stirred vigorously for an additional 16 h. After the removal of all volatiles under vacuum, the residue (30 g) was diluted with 100 mLH20, which gave a clear solution. The addition of 10 mL 5% aqueous NaOH produced a cloudy suspension that was extracted with... 

SYNTHESIS A suspension of 10 g tryptamine base in 10 g butyl formate was held at reflux for 24 h. The resulting clear solution was stripped of volatiles under vacuum, and the residue partitioned between dilute HC1 and CH2CI2, and the aqueous phase extracted twice with additional CH2CI2. The pooled organic extracts were washed once with dilute aqueous HC1, once with dilute aqueous NaOH, and the solvent removed under vacuum to give a black oil. This was distilled at the KugelRohr to give 9.05 g (11%) of... 

The quantification of D5R and other silicates during a silicalite synthesis at 95 °C from clear solution. 

Silicalite Synthesis from Clear Solution. In order to check whether the above findings on the presence of polymeric species in solution and on the fast rate of exchange between the smaller silicates are also applicable in a real zeolite synthesis mixture, we have studied a silicalite synthesis in more detail. Starting from a clear, filtered solution of molar composition 25 Si02 9 TPAOH ... 

Second, the elemental analyses of the ZSM-5 samples (20-261 prepared via standard synthesis routes do not point to missing T sites defects since these samples contain the normal (1 ) value of 3.5 - 4 TPA entities per 96 T sites (see Table IV). This observation has been confirmed by thermogravimetric measurements. Therefore, the defects in these materials are more likely to originate from hydrolysed SiOSi linkages. Interestingly, the silicalite sample prepared from clear solution at low temperature (sample 27, Table IV) most probably does contain missing T sites defects. This assertion is based on the observed high -103 ppm NMR intensity and the occlusion of more than 4 TPA entities per 96 T sites (see also Table I, samples 1-4). 

The solution of aluminum trihydride used in this synthesis is prepared by the reaction of 100% sulfuric acid with lithium tetrahydridoaluminate(l —) in dry tetrahydrofuran.3 Under nitrogen flow, a stoichiometric amount of the sulfuric acid is added dropwise by syringe at 0° to a solution of lithium tetrahydridoaluminate(l —) in dry tetrahydrofuran. The apparatus used is just like that shown in Fig. 2, except that an ice bath is used to cool the reaction flask and thus prevent ether cleavage. As the sulfuric acid is added to the lithium tetrahydridoaluminate(l —), a precipitate of lithium sulfate forms and hydrogen is evolved. For this reason, the reaction must be carried out in a hood. After all the sulfuric acid has been added, the resulting slurry is stirred for 2 hr, then filtered in a glove box.4,5 The filtrate, a clear solution of aluminum trihydride in tetrahydrofuran, is stored in the refrigerator at -20° until it is needed. 

From this example, it appears that all the inputs to NextState, the value 12, the value 5, and the variable CurrentState, should be multiplexed using appropriate select lines into the D-input of the inferred flip-flops for Next-State. This is exactly what occurs as shown in the synthesized netlist in Figure 2-55. So then, how can we infer flip-flops with synchronous preset and clear A synthesis system may provide a solution for this by providing a special option for directing the synthesis system to generate a synchronous preset clear flip-flop. 

The synthesis is normally done under atmospheric pressure. By heating and/or refluxing the mixture of RE2O3 with a stoichiometric amount of R-COOH in water or an organic solvent, such as MeOH, EtOH, DME or DMSO, a clear solution of the complex can be obtained. The product can be harvested by filtration followed by evaporation of the solvents, or by adding a less-polar solvent to the solution. About 5% in excess of RE2O3 is typically used to avoid the possible contamination from the un-reacted R-COOH, and the unused RE2O3 can then be removed by filtration after the reaction is completed. 

Monomethacrylate-functionalized POSS reagents are capable of being polymerized into novel linear silsesquioxane-based materials. Efforts to copolymerize these methacrylate-functionalized POSS with other acryhc comonomers have been successful [96,112]. In a typical polymer synthesis, a 0.5 M toluene solution of macromonomer was prepared, to which 2,2 -azobis(iso-butyronitrile) (AIBN) based on macromonomer was added from a stock solution. The clear solution was heated at 60 °C for 24 h and then precipitated into methanol. Further purification was performed by reprecipitation from toluene into methanol to yield white powder. 

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