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Abstract  

Aromatic polyamides find many applications in diverse and critical areas due to their high thermal stability coupled with high mechanical properties. However most of such aramides are difficult to fabricate because of their limited solubility and high melting temperature. Improvements in processability have been reported by incorporating bulky pendant groups and aliphatic spacer groups. Similarly to improve the solubility of polymers approaches of incorporating silicon in main polymer chain and co-polymerization techniques were useful. We report the synthesis and characterization of a series of phenylated silicon containing aromatic–aliphatic polyamides from a mixture of 2, 5-bis (4-carboxy methylene phenyl)-3, 4-diphenyl thiophene (CMPDT) and bis-(4-carboxy phenyl) dimethyl silane (BCPDS) in various mole proportions, with commercial aromatic diamine. Thus a series of novel co-polyamides having pendant phenyl groups, methylene spacer and silicon moiety was prepared by judicious combination of (CMPDT); BCPDS and aromatic diamine; bis-(4-aminophenyl) ether (ODA), by direct polycondensation using Yamazaki’s phosphorylation method. These high molecular mass polyamides were obtained in high (89–98%) yields and had viscosities in the range of 0.23–0.57 dL/g in DMAc. Polyamides showed improved solubility in polar aprotic solvents, like NMP, DMAc, DMSO and DMF; had high thermal stability; with no mass loss below 335 °C.

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Abstract  

Using physicochemical methods we showed that continuous (15 days) exposure of monazite powder in humic acid (HA) solutions with different acidity gives rise to one to two orders of magnitude growth in the concentration of the monazite’ p-, d- and f-elements of Periodic Table (Mg, Al, Si, P, Pb, Ti, Bi, Sc, Ti-Zn, REE, Th, U). The growth in the elements concentration in the humic solutions contacting monazite is shown to depend on the initial concentration of HA in the solutions, pH. It is concluded that these factors should be taken into consideration when inorganic phosphates and alike phases are used as a matrix for the radionuclide wastes solidification.

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Introduction Poor water solubility and slow dissolution into the gastrointestinal tract (GIT) are the two major obstacles impeding the pharmaceutical industry in releasing new dosage forms into the market. These issues have

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Abstract  

Literature data of solubility of MgSO3 in water and in aqueous solutions of MgSO4 have been correlated. Magnesium sulfite forms hexahydrate (stable below 40C) and trihydrate (above 40C), nevertheless, metastable hexahydrate can precipitate at temperatures significantly higher than this transition temperature. Magnesium sulfate increases the solubility of the sulfite.

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Abstract  

The solubility of magnesium-ammonium-phosphate (struvite) has been studied employing radioisotope32P as tracer. The amount of sample in solution is determined by measuring the Cherenkov radiation due to the fast -particles emitted from this radionuclide. The themodynamic solubility product is determined at various temperatures and compared with former results.

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characterized them by thermal, optical and spectral studies as well as determining their solubility. Experimental Single crystals of various proportions of thiourea urea zinc (II) chloride (hereafter abbreviated as TUZC) were prepared

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]. G.J. Price 1989 Calculation of Solubility Parameters by Inverse Gas Chromatography D.R. Lloyd T.C. Ward

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Abstract  

The solubility of palladium(II) bis-dimethylglyoximate in different solutions has been determined. The solubility is lowest in water, ammonium acetate and 25% acetone-water mixture and highest in dilute HCl.

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Progress in Agricultural Engineering Sciences
Authors: G. Zsivanovits, Ts. Grancharova, I. Dimitrova-Dyulgerova, D. Ivanova, S. Kostadinova, and M. Marudova

. Chong , J. X. , Shaojuan , L. & Hongshun , Y. ( 2015 ). Chitosan combined with calcium chloride impacts fresh-cut honeydew melon by stabilising nanostructures of sodium-carbonate-soluble pectin . Food Control , 53 , 195 – 205

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Abstract  

Polonium was precipitated from dilute solutions with metaarsenites, dichromates, iodides, molybdates, sulphites, sulphates and metavanadates. The solubility products of polonium iodide, molybdate, sulphite and sulphate were determined to be 1.92, 3.7, 3.3 and 0.9 respectively.

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